Ageless Mobility Reborn

Ageless Mobility Reborn

Faster Keto Weight Loss Review

Faster Keto Weight Loss Review

Natural Insomnia Program Review

Natural Insomnia Program Review

Atrioventricular Node and Delay of Impulse Conduction from the Atria to the Ventricles

The atrial conductive system is organized so that the cardiac impulse does not travel from the atria into the ventricles too rapidly this delay allows time for the atria to empty their blood into the ventricles before ventricular contraction begins. It is primarily the A-V node and its adjacent conductive fibers that delay this transmission into the ventricles. The A-V node is located in the posterior wall of the right atrium immediately behind the tricuspid valve, as shown in Figure 10-1. And...

Obligatory Urine Volume

The maximal concentrating ability of the kidney dictates how much urine volume must be excreted each day to rid the body of waste products of metabolism and ions that are ingested. A normal 70-kilogram human must excrete about 600 milliosmoles of solute each day. If maximal urine concentrating ability is 1200 mOsm L, the minimal volume of urine that must be excreted, called the obligatory urine volume, can be calculated as This minimal loss of volume in the urine contributes to dehydration,...

Specific Epileptic Syndromes

In contrast to seizure location and the resultant clinical manifestations, differences exist in the occurrence of epileptic syndromes in adult and pediatric epileptology. Most specific epileptic syndromes begin in childhood and may continue into adulthood. We shall start with the benign epileptic syndromes and then the malignant syndromes. Descriptions of the epileptic syndromes come from the ICES. Additional points within each syndrome are specifically referenced. The following specific...

Effects of Sympathetic and Parasympathetic Stimulation on Specific Organs

Two functions of the eyes are controlled by the autonomic nervous system. They are 1 the pupillary opening and 2 the focus of the lens. Sympathetic stimulation contracts the meridional fibers of the iris that dilate the pupil, whereas parasym-pathetic stimulation contracts the circular muscle of the iris to constrict the pupil. The parasympathetics that control the pupil are reflexly stimulated when excess light enters the eyes, which is explained in Chapter 51 this reflex reduces the...

Types of Sensory Receptors and the Sensory Stimuli They Detect

Table 46-1 lists and classifies most of the body's sensory receptors. This table shows that there are five basic types of sensory receptors (1) mechanorecep-tors, which detect mechanical compression or stretching of the receptor or of tissues adjacent to the receptor (2) thermoreceptors, which detect changes in temperature, some receptors detecting cold and others warmth (3) nociceptors (pain receptors), which detect damage occurring in the tissues, whether physical damage or chemical damage...

Factors Affecting Fungal Growth Indoors

Many environmental parameters can influence fungal growth indoors. Some are biotic factors, and others are physical and chemical, or abiotic factors. Biotic factors include the presence of fungal propagules or spores, viability of spores, the nature of the fungal species, and competing fungi and other organisms. Sampling and Analysis of Indoor Microorganisms, Edited by Chin S. Yang and Patricia A. Heinsohn Copyright 2007 John Wiley & Sons, Inc. Abiotic factors include nutrients, temperature,...

Action Potentials in Cardiac Muscle

The action potential recorded in a ventricular muscle fiber, shown in Figure 9-3, averages about 105 millivolts, which means that the intracellular potential rises from a very negative value, about -85 millivolts, between beats to a slightly positive value, about +20 millivolts, during each beat. After the initial spike, the membrane remains depolarized for about 0.2 second, exhibiting a plateau as shown in the figure, followed at the end of the plateau by abrupt repolarization. The presence of...

Economic Effects Of The Black Death

Economics is essentially the study of how people create, trade, and use goods and services. People need certain things and to have certain things done, and others provide these through their labor, at a price. Those who demand, or need, these goods and services are willing to pay for them, and they pay more for them when their need or desire for them is great or when the supply of them is small. The Black Death killed both those who demanded goods and services and those who supplied them, but...

Anatomy Of Cardiac Chambers

To understand the spatial relationships of the different cardiac chambers, three basic rules of cardiac anatomy should be remembered. First, because of the orientation of the cardiac long axis, the ventricles are more or less to the left of their corresponding atrial chambers. Second, the right atrium and the right ventricle are relatively anterior to their left counterparts. Third, because of the anterior position of the chambers of the right heart, the aorta and its valve have a central...

Iron Man Stamina Revamps Your Sexual Life

Iron Man Stamina Revamps Your Sexual Life

Penis Enlargement Remedy Review

Penis Enlargement Remedy Review

Skin Whitening Forever Review

Skin Whitening Forever Review

Edema Excess Fluid in the Tissues

Edema refers to the presence of excess fluid in the body tissues. In most instances, edema occurs mainly in the extracellular fluid compartment, but it can involve intracellular fluid as well. Two conditions are especially prone to cause intracel-lular swelling (1) depression of the metabolic systems of the tissues, and (2) lack of adequate nutrition to the cells. For example, when blood flow to a tissue is decreased, the delivery of oxygen and nutrients is reduced. If the blood flow becomes...

Effect of Potassium and Calcium Ions on Heart Function

In the discussion of membrane potentials in Chapter 5, it was pointed out that potassium ions have a marked effect on membrane potentials, and in Chapter 6 it was noted that calcium ions play an especially important role in activating the muscle contractile process. Therefore, it is to be expected that the concentration of each of these two ions in the extracellular fluids should also have important effects on cardiac pumping. Effect of Potassium Ions. Excess potassium in the extracellular...

Phosphate Buffer System

Although the phosphate buffer system is not important as an extracellular fluid buffer, it plays a major role in buffering renal tubular fluid and intracellular fluids. The main elements of the phosphate buffer system are H2PO4- and HPO4 . When a strong acid such as HCl is added to a mixture of these two substances, the hydrogen is accepted by the base HPO4 and converted to H2PO4-. HCl + Na2HPO4 > NaH2PO4 + NaCl The result of this reaction is that the strong acid, HCl, is replaced by an...

Glucose Is Transported by a Sodium CoTransport Mechanism

In the absence of sodium transport through the intestinal membrane, virtually no glucose can be absorbed. The reason is that glucose absorption occurs in a co-transport mode with active transport of sodium. There are two stages in the transport of sodium through the intestinal membrane. First is active transport of sodium ions through the basolateral membranes of the intestinal epithelial cells into the blood, thereby depleting sodium inside the epithelial cells. Second, decrease of sodium...

Absorption of Bicarbonate Ions in the Duodenum and Jejunum

Often large quantities of bicarbonate ions must be reabsorbed from the upper small intestine because large amounts of bicarbonate ions have been secreted into the duodenum in both pancreatic secretion and bile. The bicarbonate ion is absorbed in an indirect way as follows When sodium ions are absorbed, moderate amounts of hydrogen ions are secreted into the lumen of the gut in exchange for some of the sodium. These hydrogen ions in turn combine with the bicarbonate ions to form carbonic acid...

Increased Hydrogen Ion Concentration Stimulates Alveolar Ventilation

Not only does the alveolar ventilation rate influence H+ concentration by changing the Pco2 of the body fluids, but the H+ concentration affects the rate of alveolar ventilation. Thus, Figure 30-3 shows that the alveolar ventilation rate increases four to five times normal as the pH decreases from the normal value of 7.4 to the strongly acidic value of 7.0. Conversely, when plasma pH rises above 7.4, this causes a decrease in the ventilation rate. As one can see from the graph, the change in...

Stages of Recovery from Acute Myocardial Infarction

The upper left part of Figure 21-8 shows the effects of acute coronary occlusion in a patient with a small area Top, Small and large areas of coronary ischemia. Bottom, Stages of recovery from myocardial infarction. Top, Small and large areas of coronary ischemia. Bottom, Stages of recovery from myocardial infarction. of muscle ischemia to the right is shown a heart with a large area of ischemia. When the area of ischemia is small, little or no death of the muscle cells may occur, but part of...

Effects of Cortisol on Carbohydrate Metabolism

By far the best-known metabolic effect of cortisol and other glucocorticoids on metabolism is their ability to stimulate gluconeo-genesis (formation of carbohydrate from proteins and some other substances) by the liver, often increasing the rate of gluconeogenesis as much as 6- to 10-fold. This results mainly from two effects of cortisol. 1. Cortisol increases the enzymes required to convert amino acids into glucose in the liver cells. This results from the...

Effects of Cortisol on Protein Metabolism

One of the principal effects of cortisol on the metabolic systems of the body is reduction of the protein stores in essentially all body cells except those of the liver. This is caused by both decreased protein synthesis and increased catabolism of protein already in the cells. Both these effects may result from decreased amino acid transport into extra-hepatic tissues, as discussed later this probably is not the major cause, because cortisol also depresses the...

Weight Loss Breeze Review

Weight Loss Breeze Review

Energy Metabolism Factors That Influence Energy Output

As discussed in Chapter 71, energy intake is balanced with energy output in healthy adults who maintain a stable body weight. About 45 per cent of daily energy intake is derived from carbohydrates, 40 per cent from fats, and 15 per cent from proteins in the average American diet. Energy output can also be partitioned into several measurable components, including energy used for (1) performing essential metabolic functions of the body (the basal metabolic rate) (2) performing various physical...

The Biological Theory of Sensation Seeking Developed by Zuckerman

Marvin Zuckerman is one of the very few differential psychologists who have been able to develop a theory of a temperament dimension, one which skillfully combines the correlational with the experimental approach, studies on humans with research on animals, and behavior characteristics with biochemical and psy-chophysiological measures. This multidirectional approach made it possible for the author to develop a causal theory of individual differences in sensation seeking. In terms of the...

Inhibition of Gastric Secretion by Other Post Stomach Intestinal Factors

Although intestinal chyme slightly stimulates gastric secretion during the early intestinal phase of stomach secretion, it paradoxically inhibits gastric secretion at other times. This inhibition results from at least two influences. Phases of gastric secretion and their regulation. Phases of gastric secretion and their regulation. 1. The presence of food in the small intestine initiates a reverse enterogastric reflex, transmitted through the myenteric nervous system as well as through...

Martin Gruber Anastomosis

Peripheral nerve myelination begins at approximately the 15th week of gestation and continues through 3 to 5 yr of age. Therefore, for children younger than the age of 5 yr, special tables are required to evaluate NCS data. In term infants, the latency and conduction velocity values are approximately half those recorded in adults, and premature infants have even slower conduction velocities at the beginning of the third trimester, velocities are one-third of those measured in term infants. NCS...

Benign Tumors and Cysts

Benign tumors of the trachea and larynx are very rare and account for 10 of tracheal tumors.57,58 Ninety percent of tumors which are encountered in the pediatric age group are benign. Benign tumors represent a large group of diverse lesions that manifest as sharply-defined masses with no invasive characteristics.20,59 They are usually homogeneous, and the majority of lesions have no characteristic features to differentiate them by radiologic means.60 Papillomatosis is the result of a...

Physiologic Control of Glomerular Filtration and Renal Blood Flow

The determinants of GFR that are most variable and subject to physiologic control include the glomerular hydrostatic pressure and the glomerular capillary colloid osmotic pressure. These variables, in turn, are influenced by the sympathetic nervous system, hormones and autacoids (vasoactive substances that are released in the kidneys and act locally), and other feedback controls that are intrinsic to the kidneys. Sympathetic Nervous System Activation Decreases GFR Essentially all the blood...

Triple Flexion Is A Spinal Reflex

Spinal reflex pathways, results in positive symptoms including spasticity, hyperactive muscle stretch reflexes, abnormal cutaneous and autonomic reflexes, and co-contraction of agonist and antagonist muscles (dystonia). Immediately after an acute brain or spinal cord injury muscles generally become weak and hypotonic (O'Brien et al., 1996). This is referred to as spinal shock and is accompanied by loss of muscle stretch reflexes and impaired F-wave responses on nerve conduction testing...

Sympathetic and Parasympathetic Tone

Normally, the sympathetic and parasympathetic systems are continually active, and the basal rates of activity are known, respectively, as sympathetic tone and parasympathetic tone. The value of tone is that it allows a single nervous system both to increase and to decrease the activity of a stimulated organ. For instance, sympathetic tone normally keeps almost all the systemic arterioles constricted to about one half their maximum diameter. By increasing the degree of sympathetic stimulation...

Flow of Electrical Currents in the Chest Around the Heart

Figure 11-5 shows the ventricular muscle lying within the chest. Even the lungs, although mostly filled with air, conduct electricity to a surprising extent, and fluids in other tissues surrounding the heart conduct electricity even more easily. Therefore, the heart is actually suspended in a conductive medium. When one portion of the ventricles depolarizes and therefore becomes electronegative with respect to the Flow of current in the chest around partially depolarized ventricles. Flow of...

Factors That Affect the Rate of Gas Diffusion Through the Respiratory Membrane

Referring to the earlier discussion of diffusion of gases in water, one can apply the same principles and mathematical formulas to diffusion of gases through the respiratory membrane. Thus, the factors that determine how rapidly a gas will pass through the membrane are (1) the thickness of the membrane, (2) the surface area of the membrane, (3) the diffusion coefficient of the gas in the substance of the membrane, and (4) the partial pressure difference of the gas between the two sides of the...

Concept of a Set Point for Temperature Control

In the example of Figure 73-7, it is clear that at a critical body core temperature of about 37.1 C 98.8 F , drastic changes occur in the rates of both heat loss and heat production. At temperatures above this level, the rate of heat loss is greater than that of heat production, so the body temperature falls and approaches the 37.1 C level.At temperatures below this level, the rate of heat production is greater than that of heat loss, so the body temperature rises and again approaches the 37.1...

Countercurrent Exchange in the Vasa Recta Preserves Hyperosmolarity of the Renal Medulla

Blood flow must be provided to the renal medulla to supply the metabolic needs of the cells in this part of the kidney. Without a special medullary blood flow system, the solutes pumped into the renal medulla by the countercurrent multiplier system would be rapidly dissipated. There are two special features of the renal medullary blood flow that contribute to the preservation of the high solute concentrations 1. The medullary blood flow is low, accounting for less than 5 per cent of the total...

Elastic Properties of the Chest Wall

Just as the lung is elastic, so is the thoracic cage. This can be illustrated by putting air into the intrapleural space (pneumothorax). Figure 7-10 shows that the normal pressure outside the lung is subatmospheric just as it is in the jar of Figure 7-3. When air is introduced into the intrapleural space, raising the pressure to atmospheric, the lung collapses inward, and the chest wall springs outward. This Figure 7-10. The tendency of the lung to recoil to its deflated volume is balanced by...

Dead Space and Its Effect on Alveolar Ventilation

Some of the air a person breathes never reaches the gas exchange areas but simply fills respiratory passages where gas exchange does not occur, such as the nose, pharynx, and trachea. This air is called dead space air because it is not useful for gas exchange. On expiration, the air in the dead space is expired first, before any of the air from the alveoli reaches the atmosphere. Therefore, the dead space is very disadvantageous for removing the expiratory gases from the lungs. Measurement of...

Effects of Cortisol on Fat Metabolism

In much the same manner that cortisol promotes amino acid mobilization from muscle, it promotes mobilization of fatty acids from adipose tissue. This increases the concentration of free fatty acids in the plasma, which also increases their utilization for energy. Cortisol also seems to have a direct effect to enhance the oxidation of fatty acids in the cells. The mechanism by which cortisol promotes fatty acid mobilization is not completely understood. However, part...

Synthesis and Secretion of Adrenocortical Hormones

The Adrenal Cortex Has Three Distinct Layers. Figure 77-1 shows that the adrenal cortex is composed of three relatively distinct layers 1. The zona glomerulosa, a thin layer of cells that lies just underneath the capsule, constitutes about 15 per cent of the adrenal cortex. These cells are the only ones in the adrenal gland capable of secreting significant amounts of aldosterone because they contain the enzyme aldosterone synthase, which is necessary for synthesis of aldosterone. The secretion...

Regulation of Cortisol Secretion by Adrenocorticotropic Hormone from the Pituitary Gland

Unlike aldosterone secretion by the zona glomerulosa, which is controlled mainly by potassium and angiotensin acting directly on the adrenocortical cells, almost no stimuli have direct control effects on the adrenal cells that secrete cortisol. Instead, secretion of cortisol is controlled almost entirely by ACTH secreted by the anterior pituitary gland. This hormone, also called corticotropin or adrenocorticotropin, also enhances the production of adrenal...

Dynamic Stretch Reflex and Static Stretch Reflexes

Stretch reflex can be divided into two components the dynamic stretch reflex and the static stretch reflex. The dynamic stretch reflex is elicited by the potent dynamic signal transmitted from the primary sensory endings of the muscle spindles, caused by rapid stretch or unstretch. That is, when a muscle is suddenly stretched or unstretched, a strong signal is transmitted to the spinal cord this causes an instantaneous strong reflex contraction (or decrease in contraction) of the same muscle...

Function of Bile Salts in Fat Digestion and Absorption

The liver cells synthesize about 6 grams of bile salts daily. The precursor of the bile salts is cholesterol, which is either present in the diet or synthesized in the liver cells during the course of fat metabolism. The cholesterol is first converted to cholic acid or che-nodeoxycholic acid in about equal quantities. These acids in turn combine principally with glycine and to a lesser extent with taurine to form glyco- and tauro-conjugated bile acids. The salts of these acids, mainly sodium...

Blood Reservoir Function of the Veins

As pointed out in Chapter 14, more than 60 per cent of all the blood in the circulatory system is usually in the veins. For this reason and also because the veins are so compliant, it is said that the venous system serves as a blood reservoir for the circulation. When blood is lost from the body and the arterial pressure begins to fall, nervous signals are elicited from the carotid sinuses and other pressure-sensitive areas of the circulation, as discussed in Chapter 18. These in turn elicit...

Effect of Local Tissue Factors and Hormones to Cause Smooth Muscle Contraction Without Action Potentials

Probably half of all smooth muscle contraction is initiated by stimulatory factors acting directly on the smooth muscle contractile machinery and without action potentials. Two types of non-nervous and non-action potential stimulating factors often involved are 1 local tissue chemical factors and 2 various hormones. Smooth Muscle Contraction in Response to Local Tissue Chemical Factors. In Chapter 17, we discuss control of contraction of the arterioles, meta-arterioles, and pre-capillary...

Regulation of Food Intake and Energy Storage

Stability of the body's total mass and composition over long periods requires that energy intake match energy expenditure. As discussed in Chapter 72, only about 27 per cent of the energy ingested normally reaches the functional systems of the cells, and much of this is eventually converted to heat, which is generated as a result of protein metabolism, muscle activity, and activities of the various organs and tissues of the body. Excess energy intake is stored mainly as fat, whereas a deficit...

Myopathic Muscle Histopathology And The Origin Of Abnormal Electrical Activity Detected By

Myopathic states result in a variety of structural alterations in the muscle. Muscle fiber atrophy is typically produced by denervation, although it can be observed in the late stages of severe myopathies Fig. 8 . Muscle fiber hypertrophy Fig. 8 is observed in chronic muscle diseases, notably in the muscular dystrophies and in other longstanding disorders e.g., hypothyroid myopathy . Muscle fiber necrosis results in disruption and fragmentation Fig. 8. Chronic myopathic changes Emery-Dreifuss...

Sliding mechanics with light forces

In 1990, a method of controlled space closure was described3 using sliding mechanics. This has proved effective and reliable for many years, and has seen widespread acceptance by-clinicians. The authors recommend the following technique Archwires. Rectangular 019 .025 steel wires 'working wires' Fig. 9.15 are recommended with the .022 slot, because this size of wire gives good overbite control while allowing free sliding through the buccal segments. Thinner wires tend to give less overbite and...

Transmission and Processing of Signals in Neuronal Pools

The central nervous system is composed of thousands to millions of neuronal pools some of these contain few neurons, while others have vast numbers. For instance, the entire cerebral cortex could be considered to be a single large neuronal pool. Other neuronal pools include the different basal ganglia and the specific nuclei in the thalamus, cerebellum, mesen-cephalon, pons, and medulla. Also, the entire dorsal gray matter of the spinal cord could be considered one long pool of neurons. Each...

Factors That Stimulate or Inhibit Secretion of Growth Hormone

Decreased blood glucose Decreased blood free fatty acids deficiency Trauma, stress, excitement Exercise Testosterone, estrogen Deep sleep ( stages II and IV) Growth hormone-releasing hormone Increased blood glucose Increased blood free fatty hormone (somatostatin) Growth hormone (exogenous) Somatomedins (insulin-like growth factors) Protein Carbohydrate Protein Protein deficiency treatment treatment treatment (kwashiorkor) (3 days) (3 days) (25 days) Protein Carbohydrate Protein Protein...

Pupillary Syndromes Anisocoria

It is commonly written that 20 percent of the population has anisocoria of at least 0.4 mm in dim light, although published series cite highly variable percentages from 2 to 60 percent. The most common sort of variable anisocoria among healthy people has been called see-saw anisocoria or simple central anisocoria whereas the mechanism is indeterminate, this benign condition may vary from one examination to the next or even reverse sides. Light stimulation of one or both eyes decreases the...

Human Chorionic Somatomammotropin

A more recently discovered placental hormone is called human chorionic somatomammotropin. It is a protein with a molecular weight of about 38,000, and it begins to be secreted by the placenta at about the fifth week of pregnancy. Secretion of this hormone increases progressively throughout the remainder of pregnancy in direct proportion to the weight of the placenta. Although the functions of chorionic somatomammotropin are uncertain, it is secreted in quantities several times greater than all...

Decreased Cardiac Output Systolic Stretch and Cardiac

When some of the cardiac muscle fibers are not functioning and others are too weak to contract with great force, the overall pumping ability of the affected ventricle is proportionately depressed. Indeed, the overall pumping strength of the infarcted heart is often decreased more than one might expect because of a phenomenon called systolic stretch, shown in Figure 21-7. That is, when the normal portions of the ventricular muscle contract, the ischemic portion of the muscle, whether this...

Abdominal Muscle Contractions During Labor

Once uterine contractions become strong during labor, pain signals originate both from the uterus itself and from the birth canal. These signals, in addition to causing suffering, elicit neurogenic reflexes in the spinal cord to the abdominal muscles, causing intense contractions of these muscles. The abdominal contractions add greatly to the force that causes expulsion of the baby. The uterine contractions during labor begin mainly at the top of the uterine fundus and spread downward over the...

Effects Of Selenium On Athletic Performance

Most research in the area of Se and exercise has focused on the role of Se in the antioxidant enzyme GSHPx which, using GSH, converts H2O2 to water. Whole-body and especially muscle oxygen uptake increases sharply during intense physical exercise leading to increased oxidative stress.61 This oxidative stress may be related to production of ROS such as superoxide in the mitochondria during exercise. Superoxide, when acted on by superoxide dismutase (SOD), produces H2O2, which can then be...

Damping Mechanism in Smoothing Muscle Contraction

Signals from the spinal cord are often transmitted to a muscle in an unsmooth form, increasing in intensity for a few milliseconds, then decreasing in intensity, then changing to another intensity level, and so forth.When the muscle spindle apparatus is not functioning satisfactorily, the muscle contraction is jerky during the course of such a signal. This effect is demonstrated in Figure 54-5. In curve A, the muscle spindle reflex of the excited muscle is intact. Note that the contraction is...

Blood Supply To And Lymphatic Drainage Of The Female Reproductive Tract

The internal pudendal artery is the arterial trunk supplying blood to all of the perineal structure inferior to the pelvic diaphragm. It begins as a branch of the internal iliac, which is located subperitoneally in the lateral pelvis. It exits the bony pelvis, crosses the sacrospinous ligament and enters the ischiorectal fossa. At this point the artery, along with the internal pudendal vein and nerve, becomes enclosed by the obturator fascia, forming the pudendal canal. As the artery enters the...

Some Hormones That Use the Phospholipase C Second Messenger System

Angiotensin II (vascular smooth muscle) Catecholamines (a receptors) Gonadotropin-releasing hormone (GnRH) Growth hormone-releasing hormone (GHRH) Oxytocin Thyroid-releasing hormone (TRH) Vasopressin (Vi receptor, vascular smooth muscle) reticulum, and the calcium ions then have their own second messenger effects, such as smooth muscle contraction and changes in cell secretion. DAG, the other lipid second messenger, activates the enzyme protein kinase C (PKC), which then phos-phorylates a large...

Kagans Inhibited and Uninhibited Temperaments

In referring to the classifications of temperament conceptualizations presented in Table 3.1, Kagan's theory can be described as a causal, monodimensional (typological) one tending to an emotion orientation, strongly concentrated on infancy and early childhood. In spite of Kagan's long career in developmental psychology, his interest in temperament, stimulated by his own experience as well as by ideas and findings in the literature, began less than two decades ago. As delineated by Jerome Kagan...

Common Airborne And Indoor Fungi And Their Spores

Proper identification of fungi is challenging and the most important part in microscopic analysis. For spore count, only spore morphological characteristics are available. For microscopic analysis on other samples, additional fungal structures may be available. It is important for analysts to understand how to utilize available fungal structures for accurate identification and to recognize the significance of presence of certain fungi and fungal structures from perspectives of fungal biology...

Inflammation Role of Neutrophils and Macrophages

When tissue injury occurs, whether caused by bacteria, trauma, chemicals, heat, or any other phenomenon, multiple substances are released by the injured tissues Functional structures of the spleen. (Modified from Bloom W, Fawcett DW A Textbook of Histology, 10th ed. Philadelphia WB Saunders, 1975.) and cause dramatic secondary changes in the surrounding uninjured tissues. This entire complex of tissue changes is called inflammation. Inflammation is characterized by (1) vasodilation of the local...

Prevention of Blood Coagulation Outside the Body

Although blood removed from the body and held in a glass test tube normally clots in about 6 minutes, blood collected in siliconized containers often does not clot for 1 hour or more. The reason for this delay is that preparing the surfaces of the containers with silicone prevents contact activation of platelets and Factor XII, the two principal factors that initiate the intrinsic clotting mechanism. Conversely, untreated glass containers allow contact activation of the platelets and Factor...

Percutaneous Hemisection Achilles Tendon

Figure 24.3. (A) Stretching with the knee straight creates tension on the gastrocnemius. (B) Stretching with the knee bent creates tension on the soleus and deep posterior muscle compartment. as well. Commonly prescribed stretching regimens designed long term to eliminate contracture are probably more effective at preventing further contracture than at decreasing the tightness already present. Eccentric strengthening for up to one year is beneficial in reducing pain and allows for increased...

Prevention of Blood Clotting in the Normal Vascular System Intravascular Anticoagulants

Probably the most important factors for preventing clotting in the normal vascular system are 1 the smoothness of the endothelial cell surface, which prevents contact activation of the intrinsic clotting system 2 a layer of glycocalyx on the endothelium glycocalyx is a mucopolysaccharide adsorbed to the surfaces of the endothelial cells , which repels clotting factors and platelets, thereby preventing activation of clotting and 3 a protein bound with the endothelial...

Big Semen Stain In Your Underwear

Perhaps some of the fascination with these crime shows is because semen does not just leak during violent crimes. It can also leak during furtive, intimate moments that are secretly shared between consenting adults. The at-home infidelity testing industry has capitalized on a growing market of suspicious partners that want to collect physical evidence of infidelity. Reflecting another aspect of the CSI effect, infidelity tests encourage laypeople to draw definitive conclusions in their...

Some Special Characteristics of Synaptic Transmission

When excitatory synapses are repetitively stimulated at a rapid rate, the number of discharges by the postsynaptic neuron is at first very great, but the firing rate becomes progressively less in succeeding milliseconds or seconds. This is called fatigue of synaptic transmission. Fatigue is an exceedingly important characteristic of synaptic function because when areas of the nervous system become overexcited, fatigue causes them to lose this excess...

Mechanism of Blood Coagulation

More than 50 important substances that cause or affect blood coagulation have been found in the blood and in the tissues some that promote coagulation, called procoagulants, and others that inhibit coagulation, called anticoagulants. Whether blood will coagulate depends on the balance between these two groups of substances. In the blood stream, the anticoagulants normally predominate, so that the blood does not coagulate while it is circulating in the blood vessels. But when a...

Chemical Structure and Synthesis of Hormones

There are three general classes of hormones 1. Proteins and polypeptides, including hormones secreted by the anterior and posterior pituitary gland, the pancreas (insulin and glucagon), the parathyroid gland (parathyroid hormone), and many others (see Table 74-1). 2. Steroids secreted by the adrenal cortex (cortisol and aldosterone), the ovaries (estrogen and progesterone), the testes (testosterone), and the placenta (estrogen and progesterone). 3. Derivatives of the amino acid tyrosine,...

Energy System Used In Various Sport Such As Phosphagen System Almist Entirely

When comparing the same systems for endurance, the relative values are the following Phosphagen system 8 to 10 seconds Glycogen-lactic acid system 1.3 to 1.6 minutes Aerobic system Unlimited time (as long as Thus, one can readily see that the phosphagen system is the one used by the muscle for power surges of a few seconds, and the aerobic system is required for prolonged athletic activity. In between is the glycogen-lactic acid system, which is especially important for giving extra power...

Flow of Blood in the Capillaries Vasomotion

Blood usually does not flow continuously through the capillaries. Instead, it flows intermittently, turning on and off every few seconds or minutes. The cause of this intermittency is the phenomenon called vasomotion, which means intermittent contraction of the metarte-rioles and precapillary sphincters (and sometimes even the very small arterioles as well). Regulation of Vasomotion. The most important factor found thus far to affect the degree of opening and closing of the metarterioles and...

Mucocutaneous diseases associated with hiv infection

Annular scaling plaques on the nasolabial fold and cheeks. ( Drs. J. Rico and N. Prose). Infections and Infestations VIRAL INFECTIONS Herpes simplex virus (HSV) infections, and in particular chronic perianal herpes, was one of the first noted complications of HIV infection and remains a cause of significant morbidity. These patients may have persistent or recurrent painful ulcers, sometimes in the absence of vesicles, involving the genitalia, groin, perianal...

Body Fitness Prolongs Life

Multiple studies have now shown that people who maintain appropriate body fitness, using judicious regimens of exercise and weight control, have the additional benefit of prolonged life. Especially between the ages of 50 and 70, studies have shown mortality to be three times less in the most fit people than in the least fit. But why does body fitness prolong life The following are the two most evident reasons. First, body fitness and weight control greatly reduce cardiovascular disease. This...

Neurological Applications in Diagnosis and Treatment Extradural Spinal Lesions

The most common disorder seen while performing myelography is the extradural defect. Ventral extradural defects at the level of the disc space are caused by a variety of conditions, including disc bulges, disc herniations, posterior endplate spur formation, epidural hematomas, inflammatory processes, and epidural tumor, with or without associated adjacent bone involvement. Anterolateral extradural defects at the level of the disc space are routinely caused by posterolateral disc herniations,...

Effect Of Spirulina On Fatty Liver

Fatty liver is a common cause of chronic liver disease and refers to accumulation of excess fat in the liver. It is diagnosed that if fat exceeds 5 of the total weight of normal liver or when more than 30 of the hepatocytes in a liver lobule have lipid deposits, most of the fat that accumulates in the liver is triacylglycerols and fatty acids other forms of fat, such as cholesterol, cholesterol ester, and phospholipids, are also present. Fatty liver is often associated with alcoholic liver...

Primary bacterial infections pyodermas

The most common causative agents of the primary skin infections are the coagulase-positive micrococci staphylococci and the b-hemolytic streptococci. Superficial or deep bacterial lesions can be produced by these organisms. In managing the pyodermas certain general principles of treatment must be initiated. Improve the bathing habits More frequent bathing and the use of bactericidal soap, such as Dial, is indicated. Any pustules or crusts should be removed during the bathing to facilitate...

Effects of Low Oxygen Pressure on the Body

Barometric Pressures at Different Altitudes. Table 43-1 gives the approximate barometric and oxygen pressures at different altitudes, showing that at sea level, the barometric pressure is 760 mm Hg at 10,000 feet, only 523 mm Hg and at 50,000 feet, 87 mm Hg. This decrease in barometric pressure is the basic cause of all the hypoxia problems in high-altitude physiology because, as the barometric pressure decreases, the atmospheric oxygen partial pressure decreases proportionately, remaining at...

Growth Hormone Has Several Metabolic Effects

Aside from its general effect in causing growth, growth hormone has multiple specific metabolic effects, Comparison of weight gain of a rat injected daily with growth hormone with that of a normal littermate. including (1) increased rate of protein synthesis in most cells of the body (2) increased mobilization of fatty acids from adipose tissue, increased free fatty acids in the blood, and increased use of fatty acids for energy and (3) decreased rate of glucose utilization throughout the body....

Physiology of Deep Sea Diving and Other Hyperbaric Conditions

When human beings descend beneath the sea, the pressure around them increases tremendously. To keep the lungs from collapsing, air must be supplied at very high pressure to keep them inflated. This exposes the blood in the lungs also to extremely high alveolar gas pressure, a condition called hyper-barism. Beyond certain limits, these high pressures can cause tremendous alterations in body physiology and can be lethal. Relationship of Pressure to Sea Depth. A column of seawater 33 feet deep...

Conduction of Sound from the Tympanic Membrane to the Cochlea

Figure 52-1 shows the tympanic membrane commonly called the eardrum and the ossicles, which conduct sound from the tympanic membrane through the middle ear to the cochlea the inner ear . Attached to the tympanic membrane is the handle of the malleus. The malleus is bound to the incus by minute ligaments, so that whenever the malleus moves, the incus moves with it. The opposite end of the incus articulates with the stem of the stapes, and the faceplate of the stapes lies against the membranous...

Sympathetic System Often Responds by Mass Discharge In

Many instances, almost all portions of the sympathetic nervous system discharge simultaneously as a complete unit, a phenomenon called mass discharge. This frequently occurs when the hypothalamus is activated by fright or fear or severe pain. The result is a widespread reaction throughout the body called the alarm or stress response, which we shall discuss shortly. At other times, activation occurs in isolated portions of the sympathetic nervous system. The most important of these are the...

Coordination of Body Functions by Chemical Messengers

The multiple activities of the cells, tissues, and organs of the body are coordinated by the interplay of several types of chemical messenger systems 1. Neurotransmitters are released by axon terminals of neurons into the synaptic junctions and act locally to control nerve cell functions. 2. Endocrine hormones are released by glands or specialized cells into the circulating blood and influence the function of cells at another location in the body. 3. Neuroendocrine hormones are secreted by...

General Design of the Nervous System

Central Nervous System Neuron The Basic Functional Unit The central nervous system contains more than 100 billion neurons. Figure 45-1 shows a typical neuron of a type found in the brain motor cortex. Incoming signals enter this neuron through synapses located mostly on the neuronal dendrites, but also on the cell body. For different types of neurons, there may be only a few hundred or as many as 200,000 such synaptic connections from input fibers. Conversely, the output signal travels by way...

Increased Blood Volume Caused by Increased Capacity of Circulation

Any condition that increases vascular capacity will also cause the blood volume to increase to fill this extra capacity. An increase in vascular capacity initially reduces mean circulatory filling pressure (see Figure 29-12), which leads to decreased cardiac output and decreased arterial pressure. The fall in pressure causes salt and water retention by the kidneys until the blood volume increases sufficiently to fill the extra capacity. For example, in pregnancy the increased vascular capacity...

Classification Of Somatic Senses

The somatic senses can be classified into three physiologic types (1) the mechanoreceptive somatic senses, which include both tactile and position sensations that are stimulated by mechanical displacement of some tissue of the body (2) the thermoreceptive senses, which detect heat and cold and (3) the pain sense, which is activated by any factor that damages the tissues. This chapter deals with the mechanoreceptive tactile and position senses. Chapter 48 discusses the thermoreceptive and pain...

Types of Smooth Muscle

The smooth muscle of each organ is distinctive from that of most other organs in several ways (1) physical dimensions, (2) organization into bundles or sheets, (3) response to different types of stimuli, (4) characteristics of innervation, and (5) function. Yet, for the sake of simplicity, smooth muscle can generally be divided into two major types, which are shown in Figure 8-1 multi-unit smooth muscle and unitary (or single-unit) smooth muscle. Multi-Unit Smooth Muscle. This type of smooth...

Untreated Diabetes Mellitus And Respiratory Quotient

Carbohydrate Fuel Value per 100 Grams (Calories) 60.0 240 68.2 396 11.2 50 8.1 41 4.0 23 0.5 194 cent of the weight.Therefore, the fat of one pat of butter mixed with an entire helping of potato sometimes contains as much energy as the potato itself. Average Daily Requirement for Protein Is 30 to 50 Grams. Twenty to 30 grams of the body proteins are degraded and used to produce other body chemicals daily. Therefore, all cells must continue to form new proteins to take the place of those that...

Abnormalities of Growth Hormone Secretion

This term means decreased secretion of all the anterior pituitary hormones. The decrease in secretion may be congenital (present from birth), or it may occur suddenly or slowly at any time during life, most often resulting from a pituitary tumor that destroys the pituitary gland. Dwarfism. Most instances of dwarfism result from generalized deficiency of anterior pituitary secretion (panhy-popituitarism) during childhood. In general, all the physical parts of the body develop...

Specific Disorders Of The Brachial Plexus

Brachial plexopathies are most commonly caused by trauma, including closed traction injuries as well as penetrating trauma and dislocation of the humerus. The position of the arm and head is important in determining susceptibility of the brachial plexus structures during a closed injury with the arm down at the side, a force causing excessive shoulder depression will be transmitted to the upper trunk C5-6 roots , whereas with the arm overhead, force applied to the axilla is transmitted to the...

Bracket positioning and case setup

The need for accuracy 57 Patient management 57 Thcor ' of bracket positioning - avoiding errors 59 Horizontal accuracy during bracket positioning 60 Vertical bracket positioning with gauges and charts 62 Recommended bracket-positioning chart 63 Individualized bracket-positioning charts 63 Upper molar bands - rapid maxillary expansion cases 66 Lower molar band placement 67 Direct bonding of brackets 68 Indirect bonding of brackets 69 Advantages of indirect bonding 69 Disadvantages of indirect...

Pain Suppression Analgesia System in the Brain and Spinal Cord

The degree to which a person reacts to pain varies tremendously. This results partly from a capability of the brain itself to suppress input of pain signals to the nervous system by activating a pain control system, called an analgesia system. The analgesia system is shown in Figure 48-4. It consists of three major components (1) The periaqueductal gray and periventricular areas of the mesencephalon and upper pons surround the aqueduct of Sylvius and portions of the third and fourth ventricles....

The Interstitium and Interstitial Fluid

About one sixth of the total volume of the body consists of spaces between cells, which collectively are called the interstitium. The fluid in these spaces is the interstitial fluid. The structure of the interstitium is shown in Figure 16-4. It contains two major types of solid structures (1) collagen fiber bundles and (2) proteoglycan filaments. The collagen fiber bundles extend long distances in the interstitium. They are extremely strong and therefore provide most of the tensional strength...

Detection and Transmission of Tactile Sensations

Interrelations Among the Tactile Sensations of Touch, Pressure, and Vibration. Although touch, pressure, and vibration are frequently classified as separate sensations, they are all detected by the same types of receptors. There are three principal differences among them 1 touch sensation generally results from stimulation of tactile receptors in the skin or in tissues immediately beneath the skin 2 pressure sensation generally results from deformation of deeper tissues and 3 vibration...

Regulation of Aldosterone Secretion

The regulation of aldosterone secretion is so deeply intertwined with the regulation of extracellular fluid electrolyte concentrations, extracellular fluid volume, blood volume, arterial pressure, and many special aspects of renal function that it is difficult to discuss the regulation of aldosterone secretion independently of all these other factors. This subject is presented in detail in Chapters 28 and 29, to which the reader is referred. However, it is important to list here some of the...

Aortic Pressure Curve

When the left ventricle contracts, the ventricular pressure increases rapidly until the aortic valve opens. Then, after the valve opens, the pressure in the ventricle rises much less rapidly, as shown in Figure 9-5, because blood immediately flows out of the ventricle into the aorta and then into the systemic distribution arteries. The entry of blood into the arteries causes the walls of these arteries to stretch and the pressure to increase to about 120 mm Hg. Next, at the end of systole,...

Hormonal Control of Tubular Reabsorption

Precise regulation of body fluid volumes and solute concentrations requires the kidneys to excrete different solutes and water at variable rates, sometimes independently of one another. For example, when potassium intake is increased, the kidneys must excrete more potassium while maintaining normal excretion of sodium and other electrolytes. Likewise, when sodium intake is changed, the kidneys must appropriately adjust urinary sodium excretion without major changes in excretion of other...

Confluence Approaches to the Study of Creativity

Many more recent works on creativity hypothesize that multiple components must converge for creativity to occur (Amabile, 1983 Csikszentmihalyi, 1988 Gardner, 1993 Gruber, 1989 Gruber & Wallace, 1999 Lubart, 1994, 1999 Lubart, Mouchi-roud, Tordjman, & Zenasni, 2003 Mumford & Gustafson, 1988 Perkins, 1981 Simonton, 1988 Sternberg, 1985 b Sternberg & Lubart, 1991, 1995, 1996 Weisberg, 1993 Woodman & Schoenfeldt, 1989). Sternberg (1985b), for example, examined laypersons' and...

Closure of Persistent Tracheal Stoma

A persistent tracheal stoma most often has epithelial union of tracheal mucosa and cutaneous epithelium. Usually, a patient has had a stoma for a long time, frequently with an extended period of ventilation. Not infrequently, the patient is older, debilitated, or has been chronically on steroids. If the stoma fails to close spontaneously within 6 months following decannulation, it should be closed electively. A stoma may be closed by drawing muscle over the aperture, but this may lead to...

Electrodiagnosis Lumbosacral Plexopathies

Several principles of electrodiagnosis in lumbosacral plexopathy are similar to those described in the evaluation of brachial plexus lesions. The anatomy of the lumbosacral plexus is more straightforward again, considering lumbar and sacral plexus separately is helpful. In general, lesions tend to affect either one but rarely both the lumbar and sacral plexus. In cases of lumbar plexopathy, the patient generally presents with quadriceps weakness and the differential diagnostic considerations...

Anchorage control during tooth leveling and aligning

Short-term versus long-term objectives 94 Principles of anchorage control 94 Treatment sequence to show leveling and aligning 95 Recognizing the anchorage needs of a case 96 Bimaxillary retrusion - a Class 11 2 example 97 Mistakes in tooth leveling and aligning in the early years 98 Reduced anchorage needs during tooth leveling and aligning 99 Antero-posterior anchorage support during tooth leveling and aligning 100 Lacebacks for A P canine control 100 Bendbacks for A P incisor control 102 A P...

Surgical Treatment Of Benign Gastric Ulcer

With the recognized importance of H. pylori as a cause of gastric ulcer disease, surgical management should be considered only when the ulcer is refractory to nonsurgical therapy or presents with a complication such as perforation, hemorrhage, or obstruction. Gastric ulceration can be considered refractory to nonsurgical treatment if the ulcer fails to heal with optimal medical management, the patient is noncompliant with or intolerant of the medical management, or early ulcer recurrence...

Modeling and Simulation as a Teaching Tool

University of Auckland, Auckland, New Zealand Mats O. Karlsson University of Uppsala, Uppsala, Sweden This chapter briefly reviews the history of clinical trial simulation and applications of how it might be used for teaching in an academic setting. 11.2 HISTORY OF CLINICAL TRIAL SIMULATION The history of clinical trial simulation and recent applications have been reviewed by Holford et al. (1). Early clinical trial simulators were based solely on predicting the stochastic aspects of how...

Function of the Basal Ganglia in Executing Patterns of Motor Activity The Putamen Circuit

One of the principal roles of the basal ganglia in motor control is to function in association with the corti-cospinal system to control complex patterns of motor activity. An example is the writing of letters of the alphabet. When there is serious damage to the basal ganglia, the cortical system of motor control can no longer provide these patterns. Instead, one's writing becomes crude, as if one were learning for the first time how to write. Other patterns that require the basal ganglia are...

Acute Control of Local Blood Flow

Effect of Tissue Metabolism on Local Blood Flow. Figure 17-1 shows the approximate quantitative acute effect on blood flow of increasing the rate of metabolism in a local tissue, such as in a skeletal muscle. Note that an increase in metabolism up to eight times normal increases the blood flow acutely about fourfold. Acute Local Blood Flow Regulation When Oxygen Availability Changes. One of the most necessary of the metabolic nutrients is oxygen. Whenever the availability of oxygen to the...

Diagonal Stepping of All Four Limbs Mark Time Reflex If

A well-healed spinal animal (with spinal transection in the neck above the forelimb area of the cord) is held up from the floor and its legs are allowed to dangle, as shown in Figure 54-12, the stretch on the limbs occasionally elicits stepping reflexes that involve all four limbs. In general, stepping occurs diagonally between the forelimbs and hindlimbs. This diagonal response is another manifestation of reciprocal innervation, this Diagonal stepping movements exhibited by a spinal animal...

Thyroid Hormones Increase Active Transport of Ions Through

One of the enzymes that increases its activity in response to thyroid hormone is Na -K -ATPase. This in turn increases the rate of transport of both sodium and potassium ions through the cell membranes of some tissues. Because this process uses energy and increases the amount of heat produced in the body, it has been suggested that this might be one of the mechanisms by which thyroid hormone increases the body's metabolic rate. In fact, thyroid hormone also causes the cell...

Cellular Mechanism of Cortisol Action

Cortisol, like other steroid hormones, exerts its effects by first interacting with intracellular receptors in target cells. Because cortisol is lipid soluble, it can easily diffuse through the cell membrane. Once inside the cell, cortisol binds with its protein receptor in the cytoplasm, and the hormone-receptor complex then interacts with specific regulatory DNA sequences, called glucocorti-coid response elements, to induce or repress gene transcription. Other proteins in the cell, called...