Infrared spectra and structures of SiH₄ and GeH₄ dimers in low-temperature nitrogen matrixes.

IR absorption spectra of monoisotopic silane (28)SiH4 and germane (76)GeH4 are studied in nitrogen matrixes at T = 11 K. It is shown that the absorption spectra of silane and germane are similar in the regions of the ν3 stretching and ν4 bending vibrations. A significant influence of a nitrogen matrix on the absorption spectra of XH4 molecules was established.

[Emission tomography in the diagnosis of ischemic heart disease].

Myocardial perfusion scintigraphy was made at rest and during bicycle ergometer exercise to diagnose coronary heart disease (CHD), to define the site and extent of left ventricular aneurysms, and to determine the compensatory potentialities of coronary circulation, to evaluate the efficiency of drug therapy. This was performed on a two-detector emission tomograph by using 99mTc. The data obtained were processed by two protocols: 1) tomographic heart specimens and 2) large protruding eye.

[Effectiveness of propranolol in an acute test and a course of treatment in patients with stenocardia].

A comparative study of antianginal propranolol efficacy in an acute test and 7 days after regular therapy in patients with a stable form of angina of effort has shown that the duration of beta-blockade and antianginal action of the drug increases during course therapy at individual doses in a 3-4-fold regimen of administration. Sharp reduction of a degree of the antianginal effect of propranolol was noted almost in 42% of the patients on regular therapy which could be accounted for by an increase in beta-blocker negative inotropic action. In the group of patients in whom propranolol antianginal efficacy was on a decrease during course therapy, not a single clinical or hemodynamic sign was defined permitting the prediction of a reduced effect of propranolol during course therapy.

[Effect of beta-adrenoreceptor blockade on gas exchange in patients with angina pectoris during physical load].

Changes in ventilation, gas exchange and hemodynamic parameters were examined in 16 anginal patients, exposed to stepwise stress in the presence of beta-block. Physical stress of 30-60-90 W was associated with less pronounced hemodynamic response, as compared to a control bicycle-ergometric test, in anginal patients. Propranolol reduced ventilation, oxygen consumption and carbon dioxide expiration during a 30-60 W exercise.

[Anaerobic threshold: its non-invasive evaluation and relation to exertion tolerance in patients with stenocardia].

The study of changes in gas exchange, lactate and acid-base balance in 36 trained patients with angina pectoris on effort, functional class II and III during spiroergometry has demonstrated that: 1. Ventilation equivalent by oxygen is the most informative and reproducible gas exchange variable during identification of the anaerobic threshold. 2.