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31.
Summary Direct administration of d-tubocurarine into the lateral cerebral ventricle of conscious rats produced decreased metabolism, cutaneous vasodilatation and hypothermia at ambient temperatures of 8–22°C. Also, pretreatment with d-tubocurarine antagonized the arecoline-induced hypothermia.This work was supported by grants from the National Science Council of Republic of China and the Pjing-Ling Neurological Foundation (Veterans General Hospital, Taipei, Taiwan). 相似文献
32.
Salmincola californiensis is a parasitic copepod in the Lernaeopodidae family that commonly parasitizes salmonid fishes ( Oncorhynchus spp.) by attaching near the fins and on gill filaments. Historically their distribution was limited to streams that emptied into the Pacific Ocean. During the summer of 2006, several rainbow trout ( Oncorhynchus mykiss ) captured in Lake Tahoe were infested with S. californiensis . This is the first known record of S. californiensis in Lake Tahoe. 相似文献
33.
中央处理器(Central Processing Unit,CPU),作为整个计算机系统最为关键的部分,已经越来越引起业界对其设计的关注和研究兴趣。各大芯片制造商和研究机构争相推出自己的个人电脑(Personal Computer,PC)通用处理器体系结构,基于x86指令集的Intel Pentium系列和AMD Athlon系列处理器,以及基于MIPS指令集的Godson系列处理器。当今这个后PC时代,嵌入式处理器以其高性能、 相似文献
34.
遵循美国国家土地覆盖数据库2001分类主题及系统(30 m空间分辨率),研究中等分辨率成像光谱辐射仪MERIS(300 m)土地覆盖产品的发展及评价。4种监督分类器包括马氏距离、最大似然、决策树以及支持向量机被用来发展区域土地覆盖信息。结果表明:(1)支持向量机在土地特征刻画过程中分类性能最优;(2)由支持向量机导出的MERIS土地覆盖产品尽管其识别地面细节的能力不及NLCD2001,但其主要地物类型在空间分布上与NLCD2001比较接近。分析还进一步揭示MERIS数据可成功地区划水体、常绿森林、裸地及栽培作物等地物类型,而对于落叶林及灌木林的刻画则性能相对较差。在MERIS土地覆盖产品中观察到从灌木林向裸地、灌木林向常绿森林及灌木林向草地的误分现象。然而,MERIS土地覆盖产品的生产较NLCD2001要节省人力及成本,中等尺度的MERIS土地覆盖产品对于某些科学应用将具有独特的价值。MERIS土地覆盖产品的发展应该充分应用多种辅助信息以及区域调制的分类策略,以期获得更加可靠的分类结果。 相似文献
35.
Summary Dikegulac-sodium inhibited primary and lateral root growth inGlycine max. The roots, curved and showed negative geotropic response after dikegulac-sodium treatment. The tryptophan level decreased and the activity of IAA-oxidase increased with increasing concentrations of dikegulac-sodium.Acknowledgments. We are grateful to Dr R. Maag Ltd, Switzerland, for supporting this work. 相似文献
36.
Summary External irradiation resulted in an increase in thyroid131I uptake and plasma PB131I conversion ratio, whereas pretreatment with MPG reduced both the values significantly. Metabolic inhibition is suggested as a possible mechanism of action by the drug.Acknowledgment. The financial support from the CSIR, India, in the form of a research grant is gratefully acknowledged. Our thanks are also due to Prof. P. Navalkha, Radiotherapy Unit, SMS Hospital, Jaipur, for providing irradiation facilities. 相似文献
37.
Zusammenfassung Es wird der Nachweis erbracht, dass die bakterizide Wirkung der polymorph-kernigen Leukozyten bei Patienten mit nephrotischem Syndrom vermindert ist und dass Prednisolon einen günstigen Einfluss auf die Bakterizidie polymorph-kerniger Leukozyten beim nephrotischen Syndrom hat. 相似文献
38.
Multiple sclerosis is a demyelinating disease of the central nervous system and although there is little doubt that an infectious agent (or agents) is involved it has not been possible to demonstrate this unequivocally by any direct relationship to a given agent. Here we show that a significant proportion of patients with multiple sclerosis have antibodies against the paramyxovirus SV5 (simian virus 5) in their cerebrospinal fluid and in some of these such antibodies form a major proportion of the total immunoglobulin content. Further, we have been able to demonstrate that the oligoclonal bands displayed on electrophoresis of the cerebrospinal fluid of these patients can be removed by prior absorption with SV5 virus antigen. 相似文献
39.
40.
Jirawatnotai S Hu Y Michowski W Elias JE Becks L Bienvenu F Zagozdzon A Goswami T Wang YE Clark AB Kunkel TA van Harn T Xia B Correll M Quackenbush J Livingston DM Gygi SP Sicinski P 《Nature》2011,474(7350):230-234
Cyclin D1 is a component of the core cell cycle machinery. Abnormally high levels of cyclin D1 are detected in many human cancer types. To elucidate the molecular functions of cyclin D1 in human cancers, we performed a proteomic screen for cyclin D1 protein partners in several types of human tumours. Analyses of cyclin D1 interactors revealed a network of DNA repair proteins, including RAD51, a recombinase that drives the homologous recombination process. We found that cyclin D1 directly binds RAD51, and that cyclin D1-RAD51 interaction is induced by radiation. Like RAD51, cyclin D1 is recruited to DNA damage sites in a BRCA2-dependent fashion. Reduction of cyclin D1 levels in human cancer cells impaired recruitment of RAD51 to damaged DNA, impeded the homologous recombination-mediated DNA repair, and increased sensitivity of cells to radiation in vitro and in vivo. This effect was seen in cancer cells lacking the retinoblastoma protein, which do not require D-cyclins for proliferation. These findings reveal an unexpected function of a core cell cycle protein in DNA repair and suggest that targeting cyclin D1 may be beneficial also in retinoblastoma-negative cancers which are currently thought to be unaffected by cyclin D1 inhibition. 相似文献