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31 juil. 2007
ppt

Principles of Electrophysiology

Presentation - 57 pages - Medical studies

The function of the human heart requires rhythmic beatings occurring on the average 70 times a minute, 24 hours a day, for 80 or more years. The close to 3 billion contractions of the cardiac musculature that must occur without fail are coordinated by an intricate network of specialized...

31 juil. 2007
ppt

Catheterization and Angiography

Presentation - 58 pages - Medical studies

A significant reduction in coronary flow reserve is present when the ratio of flow at rest to flow after vasodilation is less than 2 : 1. Measurement of the pressure gradient across a stenosis using a small wire transducer also can assess functional severity. Fractional flow reserve is the ratio...

31 juil. 2007
ppt

Cardiovascular Magnetic Resonace Imaging

Presentation - 32 pages - Medical studies

More than any other imaging technique, cardiovascular magnetic resonance (CMR) offers the potential for dramatically changing current imaging strategies for the evaluation of patients with known or suspected cardiovascular disease. The combined attributes of superior image quality and flexibility...

25 juil. 2007
doc

The basic principle of a rocket

Worksheets - 4 pages - Physics

At first sight, a rocket seems to be about fire, noise and smoke. The basic principle of rocket is the famous Newtonian principle which says that "To every action, there is an equal and opposite action". A rocket throws mass in one direction and benefit of an equal reaction in the opposite...

20 juil. 2007
ppt

Gene Therapy

Presentation - 85 pages - Medical studies

Gene therapy is an experimental form of treatment whereby sequences of nucleic acids (i.e., genes) are delivered to cells to change their biologic function. The concept initially arose as replacement therapy for monogenic inherited disorders. For these disorders, the aim is to replace a defective...

20 juil. 2007
ppt

Drug Abuse Of Cocaine and Other Psychostimulants

Presentation - 29 pages - Medical studies

Cocaine, an alkaloid extracted from coca leaves, and other psychostimulants (e.g., amphetamine, methamphetamine) rapidly increase the concentration of several neurotransmitters in synaptic junctions and stimulate the sympathetic and central nervous systems. Topical cocaine is used in...

20 juil. 2007
ppt

Drug Abuse of Heroin and Other Opioids

Presentation - 42 pages - Medical studies

Opioids, including naturally occurring alkaloids (opiates derived from the poppy plant Papaver somniferum), semisynthetic compounds (chemically altered alkaloids), and synthetic agents, are potent analgesics and produce an intense euphoria associated with nausea; drowsiness; miosis; and a...

20 juil. 2007
ppt

Electrocardiography

Presentation - 57 pages - Medical studies

The electrocardiogram (ECG) is a recording of the electrical potentials produced by cardiac tissue. Formation of electrical impulses occurs within the conduction system of the heart. When excited, or depolarized, atrial and ventricular myocardial muscle fibers contract. The electrical currents...

20 juil. 2007
ppt

Radiology of the Heart

Presentation - 62 pages - Medical studies

The heart casts a homogeneous shadow on the chest film. No internal detail can be seen within its contours because the radiodensities of blood, myocardium, and other cardiac tissues are so similar that one cannot be distinguished from the others. Only two borders of the heart, where it contacts...

20 juil. 2007
ppt

Cardiac Function and Circulatory Control

Presentation - 90 pages - Medical studies

The heart is a muscular pump connected to the systemic and pulmonary vascular systems. Working together, the job of the heart and vasculature is to maintain adequate circulation of blood to the organs at rest and during periods of exercise. To understand perturbations that cause symptoms and...

20 juil. 2007
ppt

Myocardial Perfusion Imaging

Presentation - 44 pages - Medical studies

The techniques of nuclear cardiology permit the noninvasive imaging of myocardial perfusion under stress and resting conditions and of resting regional and global function using radionuclide imaging agents and gamma or positron cameras with associated computer processing. Myocardial perfusion...

19 juil. 2007
ppt

Epidemiology of Cardiovacular Disease

Presentation - 56 pages - Medical studies

The three major clinical manifestations of atherosclerotic cardiovascular disease (CVD) are coronary heart disease (CHD), stroke, and peripheral arterial disease (PAD). Atherosclerosis also can be found in other arterial beds, especially the renal arteries, where it causes about two thirds of...

19 juil. 2007
ppt

Principales of Occupational and Environmental Medicine

Presentation - 46 pages - Medical studies

In their work, people can be exposed to dangerous chemicals, hazardous physical agents, emotional stress, and trauma. Any of these occupational exposures can cause disease—sometimes immediately and sometimes after an interval of years or decades. In addition, tens of millions of people of...

19 juil. 2007
ppt

Drug Abuse Treatment and Relapse Prevention

Presentation - 28 pages - Medical studies

Patients who use illicit drugs benefit from treatment if they recognize that their substance use is a problem. The transtheoretical model considers a patient on a continuum from precontemplation (denial) toward maintenance (abstinence/recovery). The clinical approach should be tailored to the...

18 juil. 2007
ppt

Complementary and Alternative Medicine

Presentation - 70 pages - Medical studies

Despite dramatic advances in medical science and evidence-based practice, many people turn to other healing approaches, some derived from ancient medical traditions and others from new-age concepts. Although extraordinarily diverse in their nature and purpose, these approaches share enormous...

18 juil. 2007
ppt

Tobacco and Health

Presentation - 64 pages - Medical studies

Currently, about 46 million individuals in the United States are cigarette smokers, including 26% of men and 22% of women. People who are less well educated and/or have unskilled occupations are more likely to smoke. Smoking is responsible for about 430,000 preventable U.S. deaths annually. A...

18 juil. 2007
ppt

Ionizing Radiation Injury

Presentation - 52 pages - Medical studies

Ionizing radiation occurs as electromagnetic waves of extremely short wavelength and as accelerated atomic particles (e.g., electrons, protons, neutrons, a-particles). The injuries caused by ionizing radiation include mutagenic, carcinogenic, and teratogenic effects and various acute and...

18 juil. 2007
ppt

Inborn errors of metabolism

Presentation - 84 pages - Medical studies

Metabolism is a collective term for integrated biochemical processes of the intact organism, differentiated organ, cell, and subcellular organelle. Normal metabolism enables homeostasis for the organism by maintaining anabolic and catabolic flow of substrates to products. In the early 20th...

18 juil. 2007
ppt

Biology of Ageing

Presentation - 48 pages - Medical studies

It is useful to think of organisms as protein-synthesizing factories. If that factory is to function at very high levels of efficiency and stability for very long periods of time, the builder should start with an excellent set of blueprints (hence the importance of understanding the...

17 juil. 2007
ppt

Urinary Incontinence

Presentation - 34 pages - Medical studies

Urinary incontinence is defined as involuntary loss of urine of sufficient severity to be a health and/or social problem. Although it is commonly hidden and not discussed with health professionals, urinary incontinence is a prevalent, morbid, and expensive condition. Half of young and...

17 juil. 2007
ppt

Violence and Injury

Presentation - 41 pages - Medical studies

Serious violence and injury have life-altering consequences for victims and their families that often cannot be reversed. Prevention and treatment must be priorities. Violence in the United States is a public health epidemic that is caused by institutional and personal actions. The root causes...

16 juil. 2007
ppt

Gonococcal Infections

Presentation - 82 pages - Medical studies

Gonorrhea is a sexually transmitted infection of epithelium and commonly manifests as cervicitis, urethritis, proctitis, and conjunctivitis. If untreated, infections at these sites can lead to local complications such as endometritis, salpingitis, tuboovarian abscess, bartholinitis, peritonitis,...

03 juil. 2007
doc

Richard Dawkins, "The selfish gene"

Book review - 3 pages - Biology

In The Selfish Gene, Richard Dawkins elaborates on another perspective of Charles Darwin's theory of evolution, basing his argument on the recent discovery of the DNA molecule's structure. The theory of evolution, which relevance had been largely suffering from a lack of physical validation, now...

25 juin 2007
pdf

Ferromagnetism and the Curie-Weiss Law

Course material - 3 pages - Physics

In "Ferromagnetism and the Curie-Weiss Law" the author will start by giving a more complete derivation of the Curie-Weiss law, which might make a few points clearer. Then he will try to address some of your questions more directly. The author hopes that the derivation itself will make things...

25 juin 2007
pdf

Position of the Fermi Level for Extrinsic Semiconductors: Additional Notes for Solid State Physics

Course material - 2 pages - Physics

In "Position of the Fermi Level for Extrinsic Semiconductors" the author will talk a little more in detail about doped semiconductors. Here, the author answers the following questions: (i) What is the position of the Fermi level for an extrinsic semiconductor? (ii) What is the concentration of...

25 juin 2007
doc

Quantum Dots : A Brief Overview

Essay - 5 pages - Physics

Over the past few decades there has been immense interest in Quantum Dots. In this report the author will outline some of the fabrication techniques, basic theory, and a few important properties of QDs. There are various different kinds of Quantum Dots. The author will focus mainly on...

21 mai 2007
doc

The disposable DVD (DVD-D)

Worksheets - 3 pages - Electronics, mechanics, engineering & technology

The DVD-D is a standard DVD that can be used only for several hours after the card board sleeve has been opened. But the sleeve can be opened anytime: now, in one day, in one week, in one month or in several years. Then the DVD-D has a restricted lifespan of eight hours, after which it will be...

20 mars 2007
doc

Studying the soybean nodulation at McGill University

Essay - 32 pages - Biology

This summer I had the great opportunity to do my three months training in McGill University in Quebec, Canada. It is one of the oldest Canadian universities, considered one of the most prestigious universities in Canada and one of the best in North America. According to the Times Higher Education...

29 déc. 2006
doc

Universal Serial Bus (USB)

Essay - 4 pages - Computer science

With increasing use of the Internet, cellular telephones, communications and media in general, interconnectivity has been growing at a rate that no one could have imagined ten years ago. As a result, problems have arisen in the wireless industry related to limited bandwidth as well as connections...

29 déc. 2006
pdf

Variants on the game of Nim

Essay - 12 pages - Mathematics

Long before rock and roll, television, and computer generated dinosaurs, a group of stones was all that was needed to provide hours of entertainment and learning for the Chinese. Thousands of years ago in China, the fascinating game of Nim was created and continues to challenge minds today. Nim...