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631.
I E Petrichenko N A Shakhov YuAGratsianski O I Aleshin N V Chepurnenko N V Perova 《Experientia》1989,45(11-12):1115-1117
The study demonstrated a decreased level of glucocorticoid receptors (GR) in peripheral blood lymphocytes from hypercholesterolemic subjects, and an elevated level in patients with acute myocardial infarction. In the lymphocytes with a high GR number, dexamethasone inhibited [3H]-thymidine and [3H]-acetate incorporation into DNA and cholesterol, respectively, in the same manner as in the control cells. On the other hand, a decreased GR number resulted in a less efficient dexamethasone inhibition of the incorporation of labeled compounds. These data showed that the sensitivity of lymphocytes to glucocorticoids changed only with a decrease of GR level. 相似文献
632.
A sex pheromone produced by male cabbage looper moths, Trichoplusia ni (Hübner), has been isolated from the genital scent brushes and identified as 2-phenylethanol. It is shown conclusively to elicit specific behavioural responses in the female (such as wing vibration and abdominal elevation), as determined by a novel behavioural laboratory bioassay. This is taken as further evidence that the male pheromone of T. ni acts as a sexual stimulant (aphrodisiac) prior to mating. 2-Phenylethanol represents the first identification of a genital scent brush pheromone in the family Noctuidae, and of a male pheromone in the subfamily Plusiinae. 相似文献
633.
Thymectomized, lethally irradiated rats reconstituted with syngeneic bone marrow were injected with rat brain in complete Freund adjuvant mixture. Both, they and sham-thymectomized, irradiated and bone marrow protected rats displayed a higher incidence of leg paralysis than normal non-irradiated animals. Thymectomy lowered the incidence of the disease. 相似文献
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636.
本书论述细长桥梁或其他类似的土木工程结构在风力作用下的随机理论,为了预测这种结构在风力作用下的波动位移和截面力,需要建立计算理论,书中阐述发展这种理论所用的基本假设和方法,还给出了一些实际例子,以便读者更好地理解及应用所述的理论。 相似文献
637.
高度地概括了白俄罗斯泥炭沼泽研究进展和主要研究成果,探讨了人类活动对泥炭沼泽的影响,亦研究了白俄罗斯泥炭沼泽的开发利用,从沼泽学到沼泽业所走过的漫长而复杂的道路 相似文献
638.
N. Fraeyman G. De Bruecker A. De Schaepdryver 《Cellular and molecular life sciences : CMLS》1985,41(3):388-390
Summary Membrane resting potentials (MRP) were measured systematically in cultured mouse N2A neuroblastoma cells: 1) in the logarithmic growth phase; 2) in subconfluent cultures; 3) in confluent cultures; 4) after dBcAMP had induced morphological differentiation. Neurite extension was accompanied by a significant increase in MRP as compared to the appropriate controls. No significant differences in MRP were observed with regard to the different growth phases. 相似文献
639.
Dr. A. Shukla K. N. Agarwal G. S. Shukla 《Cellular and molecular life sciences : CMLS》1989,45(4):343-345
Summary A diet containing 18–20 mg iron/kg to young weaned rats for 8 weeks altered the metabolism of gamma-aminobutyric acid and glutamate in the central nervous system without affecting blood hemoglobin. Subsequent rehabilitation with 390 mg iron/kg diet for 2 weeks normalized these changes. 相似文献
640.
Water molecules influence molecular interactions in all biological systems, yet it is extremely difficult to understand their effects in precise atomic detail. Here we present evidence, based on highly refined atomic structures of the complexes of the L-arabinose-binding protein with L-arabinose, D-fucose and D-galactose, that bound water molecules, coupled with localized conformational changes, can govern substrate specificity and affinity. The atoms common to the three sugars are identically positioned in the binding site and the same nine strong hydrogen bonds are formed in all three complexes. Two hydrogen-bonded water molecules in the site contribute further to tight binding of L-arabinose but create an unfavourable interaction with the methyl group of D-fucose. Equally tight binding of D-galactose is attained by the replacement of one of the hydrogen-bonded water molecules by its--CH2OH group, coordinated with localized structural changes which include a shift and redirection of the hydrogen-bonding interactions of the other water molecule. These observations illustrate how ordered water molecules can contribute directly to the properties of proteins by influencing their interaction with ligands. 相似文献