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991.
992.
993.
D. K. Lvov Yu. M. Tsyrkin F. R. Karas E. M. Timopheev V. L. Gromashevski O. V. Veselovskaya N. Z. Osipova K. B. Fomina Yu. I. Grebenyuk 《Archives of virology》1973,41(3):170-174
Summary A virus strain was isolated fromVespertilio pipistrellus Schreber, 1775 while examining bats in Sokuluksk region of the Kirghiz S.S.R. in 1970. Hemagglutination inhibition tests indicated that the virus ranged among group B arboviruses. It differed essentially in complement fixation and neutralization tests from 30 viruses of the B group: Entebbe bat; Bukalasa bat; Dakar bat; Kadam; Modoc; Spondweni; Ilheus; Japanese, St. Louis, Murray Vallay and tick-borne encephalitis; Kyasanur Forest disease; Powassan; Langat; Tyuleniy; West Nile; Bussuquara; Cowbone Ridge, Uganda S; SAH-336; Kokobera; yellow fever; Dengue, types 1 and 2; Wesselsbron; Edge Hill; Alfuy; Stratford; Zika; Potuskum. It may be concluded that Sokuluk virus is a new group B virus. Complement-fixing antibodies were not found in sera of 150 cows and 200 sheep but they were detected in 0.6 percent of 579 human sera in the Kirghiz S.S.R. 相似文献
994.
Yongxing Qiu Xiaojie Yu Linxian Feng Shilin Yang 《Macromolecular chemistry and physics.》1992,193(6):1377-1385
Using the rigid and hydrophobic polystyrene (PS) chain as backbone, onto which flexible and hydrophilic stearyl-poly(ethylene oxide) (SPEO) chains are grafted, a new kind of amphiphilic, microphase-separated graft copolymer was synthesized using the macromonomer technique. Stearyl-poly(ethylene oxide) macromonomers with acryloyl end-group (SPEO-A) were prepared through an end-group exchange reaction of α-stearyl-ω-hydroxypoly(ethylene oxide) (SPEO-OH) and acryloyl chloride in the presence of triethylamine. The radical copolymerization of styrene with SPEO-A was carried out under various experimental conditions. Following a careful examination of their purity, the structure of the prepared copolymers was characterized by means of IR, 1H NMR and GPC analyses. A new feasible method using first derivative UV spectrometry was developed for quantitative determination of the bulk composition of the graft copolymers. Copolymers with a wide range of bulk composition and satisfactory grafting degree were obtained. 相似文献
995.
996.
八珍汤对血虚模型小鼠造血调控因子影响的实验研究 总被引:7,自引:0,他引:7
探讨八珍汤对由环磷酰胺引起的小鼠骨髓造血功能抑制的调控作用。采用环磷酰胺致小鼠血虚模型 ,测定八珍汤对骨髓抑制小鼠外周血象及其细胞因子产生的影响。结果表明 ,八珍汤对环磷酰胺所致血虚模型小鼠骨髓细胞有促进增殖作用 ;经八珍汤诱导制备的巨噬细胞、脾细胞、肺条件培养液和骨骼肌条件培养液能促进血虚模型小鼠骨髓细胞增殖 ,促进血虚模型小鼠骨髓基质细胞分泌肿瘤坏死因子 (TNF)。八珍汤对环磷酰胺所致化疗损伤的造血调控作用可能与直接或间接刺激造血微环境的基质细胞分泌正性和负性造血生长因子有关。 相似文献
997.
目的:探讨螺旋CT平扫和增强扫描对胃肠道间质瘤(GISTs)的诊断价值。方法:回顾性分析33例经手术、病理及免疫组化证实的GISTs患者螺旋CT表现。结果:平扫33例中,瘤体呈均匀等密度10例,肿块周边呈等密度中间略低或不均匀低密度23例。增强扫描16例中,病灶区呈中度或明显均匀强化9例,不均匀强化并可见囊状改变4例,病灶中央大片状坏死伴周边部明显强化3例。33例中良性9例,肿块直径多小于5cm,且呈圆形、类圆形,规则,边界尚清楚;恶性24例,直径多大于5cm,多数向腔外生长,边界不清楚,5例肿块中有坏死出血,4例发现转移灶。结论:螺旋CT检查对GISTs诊断虽无特异性,但可以准确定位,发现转移灶,显著提高GISTs的检出率,弥补常规胃肠道造影和内窥镜检查的不足,对GISTs术前定位和鉴别诊断均有重要价值。 相似文献
998.
Locomotion defects, together with Pins, regulates heterotrimeric G-protein signaling during Drosophila neuroblast asymmetric divisions 下载免费PDF全文
Heterotrimeric G proteins mediate asymmetric division of Drosophila neuroblasts. Free Gbetagamma appears to be crucial for the generation of an asymmetric mitotic spindle and consequently daughter cells of distinct size. However, how Gbetagamma is released from the inactive heterotrimer remains unclear. Here we show that Locomotion defects (Loco) interacts and colocalizes with Galphai and, through its GoLoco motif, acts as a guanine nucleotide dissociation inhibitor (GDI) for Galphai. Simultaneous removal of the two GoLoco motif proteins, Loco and Pins, results in defects that are essentially indistinguishable from those observed in Gbeta13F or Ggamma1 mutants, suggesting that Loco and Pins act synergistically to release free Gbetagamma in neuroblasts. Furthermore, the RGS domain of Loco can also accelerate the GTPase activity of Galphai to regulate the equilibrium between the GDP- and the GTP-bound forms of Galphai. Thus, Loco can potentially regulate heterotrimeric G-protein signaling via two distinct modes of action during Drosophila neuroblast asymmetric divisions. 相似文献
999.
Histochemical, immunohistochemical and ultrastructural studies were performed on cases of hepatocellular carcinoma (HCC) with pale bodies (PB). HCC containing PBs was observed in 3 (5.5%) of 55 consecutively resected HCC cases. Histologically, a large number of hepatocytes displayed pale or eosinophilic staining of the cytoplasm, resulting in ground-glass appearance. They were aggregated in nodular pattern, or diffusely intermixed with other malignant hepatocytes. PBs were negative for periodic-acid Schiff and Masson's trichrome staining. The inclusions showed a strong positive reaction for fibrinogen and some of them were weakly positive for albumin but negative for hepatitis B surface antigen, hepatitis B core antigen, alpha-fetoprotein and alpha-1-antitrypsin. Ultrastructurally, PBs were membrane-bound and contained granular materials of moderate electron density, and were closely related to dilated rough endoplasmic reticulum. These findings support that PBs are secretory fibrinogen accumulated in cystic ER and that such intracellular accumulation possibly reflects a defective transport of fibrinogen. 相似文献
1000.
数值模拟鼻甲的切除对鼻腔内气体流场的影响 总被引:3,自引:0,他引:3
量化研究鼻腔结构的变化对鼻腔内气体流场分布的影响.通过CT图像对鼻腔结构进行三维重建并用有限元方法对气体流场进行数值分析.对重建的鼻腔模型的一侧,分别去掉部分中鼻甲和部分下鼻甲并用有限元方法再次进行数值分析,将得到的结果与原始模型进行比较.观察气体流场分布的变化,在两侧鼻腔的流量分布均有变化,在去掉部分鼻甲的一侧流场和气压的分布也有所改变.通过数值模拟,我们量化的显示了鼻腔结构的变化对鼻腔内气体流场分布的影响. 相似文献