Premature ventricular contractions can occur in a healthy person of any age, but are more prevalent in the elderly and in men. They frequently occur spontaneously with no known cause. Heart rate turbulence (HRT) is a phenomenon representing the return to equilibrium of the heart rate after a PVC.
Microcycle is the training work unit that can be various on lasting, structure and contents. In praxa microcycles last 2-14 days, but the most often variant is 7 days.ecause of that it can be told that there is no unique, universal microcycle structure that can be thought to be equally good for each possible cases. In the theory of sports training there is multiple microcycles classifications.
Microvilli are the minute finger- like elongated projections of the plasma membrane which exhibit a core of thin microfilaments. These microfilaments are held together to form bundles by cross-linking proteins known as villin and fimbrin. The main function of the microvilli is the absorption of certain substances. Cells produce microvilli, mainly, to increase the surface area for absorption (intestine surface), to transport absorbed materials, and to participate in the digestion of carbohydrates. In general, the length of a microvillus is about 0.5 to 1.0 Âµm and the diameter is about 0.1 Âµm.