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991.
992.
Some preliminary data regarding the test of penetration and proliferation of BHK and HeLa cells biocompatibility to a three dimensional stroma saturated with phosphorous and calcium salts (a biomaterial replacing bone) are presented. These data suggest that the analysed biomaterial might be used in surgical practices of prosthesis appliance on interfaces of fractured bone.  相似文献   
993.
994.
Experiments with Coombs-sera as raw and usable sera having different levels of titre were carried out in order to examine their stability in fluid nitrogen. Therewith, significant differences concerning the storing stability did not appear. Generally seen two third of the sera retained their initial titres at the end of one year in store.  相似文献   
995.
Energy expenditure was measured during pregnancy in seven primigravid women at 12-15, 25-28, and 34-36 weeks and after the cessation of lactation. On each occasion the resting metabolic rate and the increase in metabolic rate after ingestion of a liquid test meal were measured by indirect calorimetry. In absolute terms the resting metabolic rate increased steadily during pregnancy but when expressed per unit of body weight no change was found. The energetic response to a mixed constituent meal was significantly reduced by 28% in the middle trimester of pregnancy. These findings suggest a possible maternal adaptation to increase energetic efficiency at a time when the energy demands of the fetus are high.  相似文献   
996.
Previously, it was found that the ancient Chinese remedy of Suanzaorentang could be a promising anxiolytic drug (Chen and Hsieh, 1985a, Chen and Hsieh, 1985b). To understand the mechanism of the action of Suanzaorentang, the effects of Suanzaorentang on behavior changes and central monoamines and their metabolites were studied in rats. It was found that Suanzaorentang significantly (1) prolonged the period from the onset of clonic to tonic convulsions induced by pentylenetetrazol or picrotoxin, (2) prolonged the sleep duration induced by hexobarbital, (3) reduced locomotor activity, (4) enhanced the hypomotility induced by alpha-MT, (5) reduced the locomotor stimulation produced by levodopa plus benserazide, and (6) reduced central HVA, VMA, and 5-HIAA, but had no significant effects on central DA, NA, and 5-HT. These facts implied that Suanzaorentang decreased the turnover rate of central monoamines and central catecholaminergic activity.  相似文献   
997.
998.
All-trans-retinol induced aggregation of rabbit platelets, and this effect could be inhibited by a cyclooxygenase inhibitor and a thromboxane A2 (TXA2) receptor antagonist, indicating an essential role for endogenously produced TXA2. We found a two-phase arachidonic acid release in retinol-stimulated platelets. The first phase was induced by the action of retinol alone and not inhibited by TXA2 receptor antagonist. The second phase was induced via synergistic action of retinol and initially generated small amount of TXA2, and was inhibited by the antagonist. Moreover, we discussed that the arachidonic acid release may be mediated by the action of phospholipase A2.  相似文献   
999.
1000.
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