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991.
A symmetrical view of the T-cell receptor-CD3 complex. 总被引:1,自引:0,他引:1
992.
Segmental aortic wall stiffness was calculated from intravascular ultrasound images and intravascular pressures in six pigs at normal and subnormal aortic pressures (21 sequences of pressures and areas before and after boli of intravenous nitroglycerin). The wall stiffness was expressed as the pressure-strain elastic modulus (Ep). The Ep was calculated from the formula: Ep = delta PR delta R-1 (P, pressure; R, radius) in two different ways. First from maximal and minimal values of pressure and area. Second as the slope of linear regression line of delta PR as a function of delta R from 29 simultaneous recorded pressures and images. The average Ep value for all sequences in the different segments was 0.58 +/- 0.55 10(5) Pa (Method 1) and 0.50 +/- 0.40 10(5) Pa (Method 2). Ep increased with the distance from the heart at normal aortic pressures. At subnormal aortic pressures after intravenous nitroglycerin this relationship was not so evident. At subnormal aortic pressures the calculated Ep values were significantly reduced in the lower half of the abdominal aorta. The phase lag, i.e. hysteresis, between pressure and diameter was demonstrated. Our study shows the applicability of intravascular ultrasound as a tool to evaluate arterial wall stiffness. 相似文献
993.
Concentration and metabolic replacement (turnover) rate of glucose and ketone bodies were determined at intervals during a 52 day postweaning fast in five grey seal (Halichoerus grypus) pups, using bolus injections of radiotracers. Blood glucose was maintained at a high level throughout the fast, while beta-hydroxybutyrate increased 26 times from day 3 to day 37, whereafter it by and large was maintained. Glucose replacement rate decreased to 56% of the day 9 value at day 37 and dropped further to only 32% of the day 9 level at day 52 in two seals, while in another 2 seals it increased at this late stage. The average ketone body replacement rate ranged between 8.6 and 13.8 mumols min-1 kg-1, but did not change significantly (P greater than 0.05) during the fasting period. These results suggest a reduced gluconeogenesis from protein and increased production of ketone bodies, which may in part replace glucose as energy source during fasting. 相似文献
994.
Interindividual variability of lung function responses to smoking is unexplained. The aim of the present study is to inquire about a possible role of personality factors for an explanation of interindividual differences of lung function responses in smokers of both sexes. The results of canonical correlation analyses showed that there are no substantial correlations of personality with smoking behavior and also no significant associations of smoking behavior with pulmonary function in a healthy sample of smokers. In males only, personality factors were related to breathing frequency, but not to static and dynamic lung volumes. 相似文献
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A G Kurmukov M I A?zikov S A Rasulova O Kh Makhmudov 《Farmakologiia i toksikologiia》1986,49(6):54-57
Amorphin--24-vicyanoside (C34H4O16(2)H2O)--in a dose of 10 mg/kg orally decreases the content of cholesterol, total lipids, atherogenic lipoproteids in the blood and organs of intact rats and rats with endogenous or ethanol hyperlipemia, inhibits the development of experimental atherosclerosis in rabbits induced by the combination of risk factors (cholesterol + glucose + hypodynamia), decreases the content of lipids in the blood and organs (especially in aorta), prevents the development of morphological manifestations of the aorta atherosclerosis. 相似文献
1000.
The purpose of the present paper was to demonstrate the antitumor activity of lymphocytes and antibodies in the antibody-dependent cell-mediated cytotoxicity test (ADCC) in relation to the tumor growth in adult and aging rats bearing a methylcholanthrene-induced sarcoma (MC-Sa). In the syngeneic system using the ADCC test effector spleen lymphocytes, 51Cr labeled MC-Sa target cells and anti-MC-Sa serum were derived from inbred male Wistar rats. It was found that adult and aging tumor-bearing rats possessed lymphocytes (LSa) and antibodies (Ab) which were active in ADCC. In comparative studies between the groups of adult and aging rats a reverse relationship between tumor growth and activity of LSa and Ab in the ADCC test has been found. Thus, the larger weight of tumors in the group of adult rats was followed by lower LSa and Ab activities in the ADCC test. On the other hand, the smaller tumor growth in the group of aging rats was followed by higher activities of LSa and Ab in this test. We suggest that the ADCC phenomenon could be one of the antitumor mechanisms especially effective in aging rats. 相似文献