Haemostasis is a process in which a blood clot is formed in the wall of a damaged blood vessel. Haemostasis thus prevents blood loss while maintaining blood fluidity within the…

The autonomic nervous system plays an important role in various pathological situations such as myocardial infarction, congestive heart failure or diabetic neuropathy and is strongly implicated in the pathogenesis of…

The interpretation of the electroencephalographic signal is often limited to the assumption  that the electrode placed directly above the source of the signal detects the largest potential, whereas more distant…

The autonomic nervous system plays a crucial role in the cardiovascular response to exercise. During exercise, oxygen uptake increases to meet increased energy consumption. Central command, baroreflex with its resetting,…

During physical exercise, the production of heat in the working skeletal muscles increases tremendously, inducing an increase in core temperature, which can increase for up to two degrees or more.…

The energy consumption of the human body increases during physical exercise, especially in the active muscle cells. The synthesis of ATP, the unique direct energy source in skeletal muscles, depends…

Membrane potential depends on the concentration gradient of ions across the membrane and on the membrane permeability for these ions. The resting membrane potential of most cells has a negative…

The first part of this article considers the Nernst potential of a particular species of ions as the difference in electrical potential between two regions that exactly balances the difference…

Human retina contains two types of photoreceptors. Rods are very sensitive and enable vision in dim light conditions, whereas cones mediate daylight vision and color detection. In photoreceptors, absorption of…

Exocytosis, part of which is the merger of the vesicle and the plasma membrane, is charac­teristic for eukaryotic cells, which engage this process in a myriad of cell functions. For…

Endothelial dysfunction represents one of the earliest changes in arterial function and is an important event in the atherosclerotic process. Reduced production or bioavailability of nitric oxide is the most…

BACKGROUNDS. Heart rate variability increases with increased vagal effect. Compared to seden­tary individuals, athletes have an increased vagal tone. Their resting heart rate decreases and heart rate variability increases. The…

We are introducing pain as a very personal sensation, which is very difficult to define precisely due to its multidimensional nature. Not solely the biological side of sensation, but also…

Skeletal muscle is the most abundant of the human body's tissues and it represents a substantial percentage of body mass. Its main function is contraction, which produces force for different types…

In the third and final part of our review, we thoroughly and quantitatively analyse the influence of alveolar dead space ventilation and shunt on the pulmonary exchange of gases and…

Metabolically produced CO2 diffuses into tissue capillaries and flows convectively via the bloodstream into alveolar capillaries. There it diffuses across the alveolocapillary membrane into the alveoli, from where it is…

Inspired air flows down the airways to reach the alveoli. Along this way, the temperature of this relatively small volume of air equilibrates with body temperature and becomes saturated with…

Background. The functional integration (»binding«) of different brain areas, for example as a possible mechanism for stimulus perception, may be mediated by the synchronizing oscil­latory activity of neuronal populations, which…

It is well documented that exposure to a hypoxic environment affects visual and auditory perception and attenuates cognitive function in humans. Since the perception of thermal stim­uli is indispensable for…

Negative feedback is one of the most difficult topics in physiology, possibly because descrip­tive thinking is useless. Instead, to analyse single constituents quantitatively or semiquantitatively, causal thinking is mandatory. By…

The endocardial surface and the volume of the left ventricle were determined experimentally by an original noninvasive method with the goal of understanding the mechanism of the influence of the…

In spite of long term expectations of the discovery of heart natriuretic substance only nine years ago the atrial natriuretic peptide was discovered. Some essential data about structure, synthesis, secretion…

Anatomy and physiology of nervous structures involved in temperature and pain perception, as well as single sensations, receptive structures and afferent nerve fibers are defined. Peripheral nerves and spinal cord…

The paper surveys the physiological aspects of androgens. It describes in more detail synthesis of C19 steroids, their metabolism and transport, and presents serum salivary levels of individual androgens in…