Why Does the Heart Beat?
نویسندگان
چکیده
منابع مشابه
Why does the heart beat? The discovery of the electrical system of the heart.
Why does the heart beat? This question--known as the myogenic versus neurogenic theory--dominated cardiac research in the 19th century. In 1839, Jan Evangelista Purkinje discovered gelatinous fibers in the ventricular subendocardium that he thought were muscular. Walter Gaskell, in 1886, demonstrated specialized muscle fibers joining the atria and ventricles that caused "block" when cut and fou...
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The French Academy units of time and length — the second and the meter — are traditionally considered independent from each other. However, it is a matter of fact that a meter simple pendulum beats virtually the second in each oscillation, a 'surprising' coincidence that has no physical reason. We shortly review the steps that led to the choice of the meter as the ten millionth part of the quad...
متن کامل1 4 D ec 2 00 4 Why does the meter beat the second ?
The French Academy units of time and length — the second and the meter — are traditionally considered independent from each other. However, it is a matter of fact that a meter simple pendulum beats virtually the second in each semi oscillation, a 'surprising' coincidence that has no physical reason. We shortly review the steps that led to the choice of the meter as the ten millionth part of the...
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ژورنال
عنوان ژورنال: Circulation
سال: 2006
ISSN: 0009-7322,1524-4539
DOI: 10.1161/circulationaha.106.616771