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71.
72.
本文从以下七个方面阐述了灯光在电视节目创作中的作用和地位。1.观众注意力的引导;2. 画面特点;3.画面形象的空间、主体、比例和透视关系;4.画面形象的形态、轮廓和体积的表现;5. 画面构图和影调的关系;6.画面的影调平衡和视觉连续性;7.光的造型。  相似文献   
73.
Experiments on CBA mice with alcohol withdrawal syndrome showed a reduction of abstinence after injection of serotonin antibodies in dose 5 and 10 mg intraperitoneally. One more result was a decrease of horizontal locomotory activity after injection of 5 mg of serotonin antibodies to mice with 24 hour withdrawal syndrome.  相似文献   
74.
The regulation of plasma lecithin:cholesterol acyltransferase (LCAT) expression is not well understood. Although oleic acid increases both the secretion of triglycerides and LCAT by primary rat hepatocytes, the effect of other fatty acids (FA) on LCAT secretion is not known. This study was designed to examine the effect of FA on the hepatic secretion of LCAT, triglyceride and apolipoprotein A-1 (apoA-1). Primary rat hepatocytes were incubated with serum-free medium, supplemented with individual FA (0-1 mmol/L) for 22-24 h. Preliminary studies indicated a linear secretion of LCAT up to 24 h in both control and FA-treated cells. When hepatocytes were incubated with 1 mmol/L FA, the LCAT secretion increased 50-100% (P < 0.01) in the presence of the 18-carbon FA (stearic, oleic, elaidic and linoleic acids), whereas the presence of butyric, lauric and palmitic acids had no significant effect. LCAT secretion decreased (P < 0.01) in the presence of docosahexaenoic acid (DHA). All FA (except DHA) significantly enhanced triglyceride secretion; however, only the 18 carbon FA significantly stimulated the synthesis and secretion of apoA-1 and secretion of LCAT. The secretion of LCAT correlated with apoA-1 secretion (r = 0.88, P = 0.004) but not with triglyceride secretion (r = 0.55, P = 0.12). Treatment with oleic acid resulted in a 1.5-fold increase in hepatocyte LCAT mRNA accumulation, whereas butyrate and palmitate had no effect. These data indicate that FA that promote the apparent synthesis and secretion of apoA-1 also stimulate the secretion of LCAT in vitro, suggesting a coordinate regulatory mechanism for apoA-1 and LCAT expression.  相似文献   
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The effects of acetylcholine on both pyramidal neurons and interneurons in the area CA1 of the rat hippocampus were examined, using intracellular recording techniques in an in vitro slice preparation. In current-clamp mode, fast local application of acetylcholine (ACh) to the soma of inhibitory interneurons in stratum radiatum resulted in depolarization and rapid firing of action potentials. Under voltage-clamp, ACh produced fast, rapidly desensitizing inward currents that were insensitive to atropine but that were blocked by nanomolar concentrations of the nicotinic alpha7 receptor-selective antagonists alpha-bungarotoxin (alphaBgTx) and methyllycaconitine. Nicotinic receptor antagonists that are not selective for alpha7-containing receptors had little (mecamylamine) or no effect (dihydro-beta-erythroidine) on the ACh-induced currents. Glutamate receptor antagonists had no effect on the ACh-evoked response, indicating that the current was not mediated by presynaptic facilitation of glutamate release. However, the current could be desensitized almost completely by bath superfusion with 100 nM nicotine. In contrast to those actions on interneurons, application of ACh to the soma of CA1 pyramidal cells did not produce a detectable current. Radioligand-binding experiments with [125I]-alphaBgTx demonstrated that stratum radiatum interneurons express alpha7-containing nAChRs, and in situ hybridization revealed significant amounts of alpha7 mRNA. CA1 pyramidal cells did not show specific binding of [125I]-alphaBgTx and only low levels of alpha7 mRNA. These results suggest that, in addition to their proposed presynaptic role in modulating transmitter release, alpha7-containing nAChRs also may play a postsynaptic role in the excitation of hippocampal interneurons. By desensitizing these receptors, nicotine may disrupt this action and indirectly excite pyramidal neurons by reducing GABAergic inhibition.  相似文献   
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Optimal conditions for in vitro cultivation of mouse embryos were sought. The embryos at 8--9.5 days of development were explanted into the culture in rotating tubes. A number of nutritional media were studied: the human umbilical blood serum; the rat blood serum, as well as its mixture (1 : 1) with Eagle's medium. It was demonstrated that the optimal medium for cultivation of 8-day-old embryos was the mixture of the rat blood serum with Eagle's medium, and for 8.5--9.5-day-old embryos--the rat blood serum, as well. Comparing in vitro and in vivo embryonic development, it was evident that in the cultivated embryos the parameters characterizing their growth decreased significantly. Possible causes of this phenomenon are discussed.  相似文献   
79.
AIM: Analysis of cytostatic therapy effects on expression of gene MDR-1 in hemopoietic cells of patients with acute leukemia (AL) in complete clinicohematological remission (CCHR). MATERIALS AND METHODS: The study included 48 AL patients. 27 of them were untreated, 25 were resistant to or had recurrent AL. 4 patients were followed up. Bone marrow mononuclear fraction was investigated. Expression of MDR-1 gene in the cells was evaluated at hybridization. RESULTS: High expression of MDR-1 gene occurred in leukemic blast cells either upon achievement of CCHR or at least 6 months after its onset. When using schemes of chemotherapy containing two potential inductors of gene MDR-1, expression of this gene was registered significantly more frequently than in using schemes based on one inducing drug (p < 0.05). Frequency of occurrence of enhanced expression of gene MDR-1 in leukemic blasts significantly correlated with frequency of CCHR (p < 0.05). Correlation between occurrence of the gene's expression in normal hemopoietic cells in CCHR and occurrence of early AL recurrences was not found. CONCLUSION: The findings may facilitate design of new AL treatment programs.  相似文献   
80.
Soluble antigens of sheep and goat poxviruses (SPV, GPV) were isolated and purified from scab suspensions prepared from lesions of experimentally infected homologous hosts. The soluble antigens were then subjected to sequential ammonium sulphate precipitation. All the obtained fractions reacted in counter immunoelectrophoresis (CIE) with both the antisera against SPV and GPV except the fraction obtained at 30% saturation level (30% SSPV), which did not react with antiserum against GPV. This differentiating soluble SPV antigen was found to consist of 210 K proteins in exclusion chromatography. The 210 K proteins contained 3 polypeptides of 100, 35 and 17 K in polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate (SDS-PAGE). The study thus gave an evidence that the SPV-specific proteins are of a higher molecular mass nature.  相似文献   
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