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- 1. distance learning; distance education (A method of instruction and learning designed to overcome barriers of time and space by allowing students to study in their own homes or at local facilities, often at their own convenience, using materials available electronically or by mail. Contact with the instructor usually occurs via telephone or e-mail. Telecommunication networks and teleconferencing have facilitated distance learning. Libraries are working to support distance learning by providing online catalogs and databases, electronic reserves, electronic reference service, online tutorials, and electronic document delivery.)
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2020年8月13日 · Use WebMD’s Drug Interaction Checker tool to find and identify potentially harmful and unsafe combinations of prescription medications by entering two or more drugs in question.
The leading source for trustworthy and timely health and medical news and information. Providing credible health information, supportive community, and educational services by blending award ...
- Pathophysiology
- Significance
- Signs and symptoms
- Overview
- Prognosis
A blood pressure reading appears as two numbers. The first and higher of the two is a measure of systolic pressure, or the pressure in the arteries when the heart beats and fills them with blood. The second number measures diastolic pressure, or the pressure in the arteries when the heart rests between beats.
Optimal blood pressure is less than 120/80 (systolic/diastolic). In healthy people, low blood pressure without any symptoms is not usually a concern and does not need to be treated. But low blood pressure can be a sign of an underlying problem -- especially in the elderly -- where it may cause inadequate blood flow to the heart, brain, and other vi...
Chronic low blood pressure with no symptoms is almost never serious. But health problems can occur when blood pressure drops suddenly and the brain is deprived of an adequate blood supply. This can lead to dizziness or lightheadedness. Sudden drops in blood pressure most commonly occur in someone who's rising from a lying down or sitting position t...
Postural hypotension is considered a failure of the cardiovascular system or nervous system to react appropriately to sudden changes. Normally, when you stand up, some blood pools in your lower extremities. Uncorrected, this would cause your blood pressure to fall. But your body normally compensates by sending messages to your heart to beat faster ...
The risk of both low and high blood pressure normally increases with age due in part to normal changes during aging. In addition, blood flow to the heart muscle and the brain declines with age, often as a result of plaque buildup in blood vessels. An estimated 10% to 20% of people over age 65 have postural hypotension.
2015年1月16日 · Get the nutrition lowdown on all your meals and everything in between. Find out the calories, carbs, fat, fiber, and more in over 37,000 foods and drinks. Whether you're eating out or dining in ...
2023年4月2日 · Endodontists treat problems involving the inside of the tooth, an area known as the “tooth pulp .”. It has blood vessels, nerves, and connective tissue. It can get inflamed or infected because ...
2023年11月7日 · In your brain, this causes a stroke; in your heart, a heart attack. The process of atherosclerosis begins with: Fatty streak. A yellow strip lining the walls of major arteries, fatty streak has ...
2021年10月31日 · Causes of Stomatitis: Canker Sores and Cold Sores. Canker Sores. Nobody knows what exactly causes canker sores, but many things may contribute to their development, such as certain medications ...
