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.

[Methodological aspects of using the exercise test during clinico-pharmacological trials of anti-angina preparations].

Studies of physical stress tolerance in 37 patients with angina of effort subjected to repeated bicycle ergometry demonstrated a systematic increment in physical stress tolerance that included an adaptation stage (first 2 or 3 exercise sessions) and a slow-training stage that followed. The adaptation stage was characterized by a significant increase in the duration of the effort and the output. The training stage was represented by a moderate tolerance increment that never exceeded the range of accidental tolerance variation from one exercise period to another.

[Duration of the hemodynamic effect of various doses of delayed-action nitroglycerin preparations].

In 113 patients with coronary disease finger rheoplethysmography was used to study the duration of the hemodynamic effect of nitroglycerin drugs of prolonged action (NDPA) as compared to placebo. Nitrong and sustac in doses of 2.5 and 2.

[Calcium antagonists in stress angina pectoris (pharmacodynamic study)].

In 10 patients with stress stenocardia pharmacodynamics of Isoptin was studied with the aid of identical physical loads on the treadmill repeated with an hour's interval for 5-6 hours. A clearcut antianginal effect was recorded which consisted in the reduction of ST segment depression and of the pain syndrome for 5 hours after administration of 3 tablets over 5 hours and for 6 hrs 20 min after administration of 5 tablets of both drugs. The degree of effect increased considerably after the dose of isoptin was enhanced and was not changed after the dose of corinfar was enhanced.

[Sustak pharmacodynamics in effort stenocardia].

Sustak pharmacodynamics was studied in 32 patients with stable angina pectoris of effort during acute tests with dosaged physical exercises repeated a tone-hour intervals. The results were compared with those in placebo. It is shown that the duration and pronounced character of the antianginal sustak effect varies widely in different patients.

[Pharmacodynamics of nitroglycerin for sublingual medication in ischemic heart disease].

The hemodynamic effect of sublingual nitroglycerin (0.5 mg) was studied in 113 patients with ischemic heart disease by means of tetrapolar finger rheoplethysmography and impedance-cardiography. A decrease in systemic arterial pressure, stroke and minute cardiac indices and ejection period, and increase in the rate of cardiac rhythm were found.

[Comparative pharmacodynamics study of korinfar and isoptin in ischemic heart disease].

The effect of Korinfar (30 and 50 mg) and isoptin (120 and 200 mg) on exercise tolerance was studied in 11 patients with angina pectoris of effort using the double blind crossover method. Both doses of Korinfar and 120 mg of isoptin increased cardiac output by 70--80% and 200 mg of isoptin--by 136%. Korinfar had a pronounced growth hypotensive effect and induced tachycardia, which is an increased dose hindered growth of exercise tolerance.

[Pharmacodynamic study of nitroglycerin preparations by methods of tetrapolar rheoplethysmography of the finger and impedance cardiography in ischemic heart disease].

A method of tetrapolar impedance plethysmography of the finger (TIPF) is suggested for the evaluation of the peripheral hemodynamic effect of drugs containing nitroglycerin. The method is based on the changes in the beta wave amplitude in TIPF as compared to the initial level. The central hemodynamics was studied by means of impedance cardiography (by the cardiac index) simultaneously with TIPF.