effects of acute systemic hypoxia on the cardiovascular system (cys) and respiration of spontaneously breathing cats were studied in two conditions. 1): hypoxic air (6-8% 02 in n2) was given to the animal to induce systemic hypoxia for 20 minutes. hyperventilation at this condition lowered arterial c02 tension (pac02 hypocapnia). 2): in the second run, induction of hypocapnia was prevented by a...

introduction: nitric oxide is an important endogenous compound that acts as bronchodilator in trachea. electromagnetic fields (emf) affect nitric oxide level in different tissues. the interaction of nitrergic and cholinergic systems in airways has been reported. therefore, the present study was performed to evaluate the interaction of cholinergic and nitrergic systems in the trachea of rats tha...

introduction: the ability to accurately measure forces produced by orthodontic appliances during orthodontic treatment is desirable. the aim of the present study was to compare forces measured by mechanical formulae designed with a software program and those experimentally measured by a dynamometer to find a scientific way to determine the exact amount of activation needed for applying a force ...

many patients fear about neurological disorders because of mistrust to their judgments. reality is that neurological system is one of the simplest systems, but unfortunately we discuss about it in a form that induce fear to people. suppose that an old person hospitalized for cerebro-vascular accident (cva) and increased intracranial pressure (icp). results of your assessment can increase patien...

influenza is an acute respiratory disease caused by the influenza a or b virus. it often occurs in outbreaks and epidemics worldwide, mainly during the winter season. significant numbers of influenza virus particles are present in the respiratory secretions of infected persons, so infection can be transmitted by sneezing and coughing via large particle droplets. the mean duration of influenza v...