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91.
本文采用散斑法对两种不同铺层方式的环氧基———玻璃纤维复合材料层合板的弹性模量,泊松比及应力应变分布进行了测试研究,给出了相应的实验数据,为理论计算方法的研究提供了有关参数  相似文献   
92.
This paper deals with the immune reaction betweenTrypanosoma gambiense and monoclonal IgM mouse antibody at equivalence with or without rabbit complement. Antibody-mediated trypanosome clumps formed in the absence of complement, and were readily dissociated by complement to become free. In the presence of complement, on the other hand,T. gambiense were not aggregated by the antibody. Free parasites adhered readily to cultured peritoneal macrophages. Complement-mediated dissociation of the clumped trypanosomes in the equivalence area released a large number of previously bound surface antigens. These antigens were capable of binding again to fresh IgM antibody. Experimental results further indicated that the complement system caused a functional alteration, changing the multivalent nature of the IgM antibody in the immune complex into a univalent one. This phenomenon is of great advantage to the infected host in clearing pathogens in vivo, as it allows more antibodies to attach to trypanosomes and subsequently initiate complement activity.  相似文献   
93.
A single whole-body X-irradiation of pregnant Wistar rats at a dose of 1.05 Gy at 10.30, 12.30 and 14.30 h respectively, of gestational day 10 resulted in significantly high incidences of hydrocephalic offspring. No hydrocephalic offspring resulted from X-irradiation of pregnant rats with 1.05 Gy at 16.30 h, whereas a dose of 1.22 Gy at 16.30 h resulted in a low but statistically significant incidence of hydrocephalus. Neither 1.05 Gy nor 1.22 Gy X-irradiation of pregnant rats at 18.30 h resulted in any hydrocephalic offspring. Dysplasia of the subcommissural organ was noticed in all the hydrocephalic brains histologically examined.  相似文献   
94.
Gastric cancer is one of the most aggressive malignancies, with limited treatment options in both locally advanced and metastatic setting, resulting in poor prognosis. Based on genomic characterization, stomach tumour has recently been described as a heterogeneous disease composed by different subtypes, each of them with peculiar molecular aspects and specific clinical behaviour. With an incidence of 22% among all western gastric tumour cases, stomach cancer with microsatellite instability was identified as one of these subgroups. Retrospective studies and limited prospective trials reported differences between gastric cancers with microsatellite stability and those with instability, mainly concerning clinical and pathological features, but also in regard to immunological microenvironment, correlation with prognostic value, and responses to treatment. In particular, gastric cancer with microsatellite instability constitutes a small but relevant subgroup associated with older age, female sex, distal stomach location, and lower number of lymph-node metastases. Emerging data attribute to microsatellite instability status a favourable prognostic meaning, whereas the poor outcomes reported after perioperative chemotherapy administration suggest a detrimental role of cytotoxic drugs in this gastric cancer subgroup. The strong immunogenicity and the widespread expression of immune-checkpoint ligands make microsatellite instability subtype more vulnerable to immunotherapeutic approach, e.g., with anti-PD-L1 and anti-CTLA4 antibodies. Since gastric cancer with microsatellite instability shows specific features and clinical behaviour not overlapping with microsatellite stable disease, microsatellite instability test might be suitable for inclusion in a diagnostic setting for all tumour stages to guarantee the most targeted and effective treatment to every patient.  相似文献   
95.
Summary 7 monoterpenes, -pinene, -pinene, myrcene, p-cymene, limonene, neral and geranial, were identified together with n-undecane in the scent scales ofP. melete, and also, together with considerable amounts of linalool, in the scent scales ofP. napi. Content ratio of neral to geranial inP. melete ranged from 0.77 to 1.04, and that inP. napi from 1.84 to 2.43. The present chemotaxonomic approach shows the 2 species ofPieris to be distinct.The authors thank Dr T. Yushima (National Institute of Agricultural Science, Japan) for supplying the references 3 and 4.  相似文献   
96.
针对"科技与社会"研究栏目以及各主要专题,本文对"科技哲学"三种主要期刊在1979-2008年间所刊载的有关论文进行了统计分析,给出中国近三十年"科技与社会"研究总的概况、各专题研究概况以及各专题主题研究概况。  相似文献   
97.
The urbanization process is a trend occurring inevitably in the historical development. This paper reviews the progress of the urbanization in Guangzhou and focuses on the change of water quality in the Guangzhou reach of the Pearl River. 8 kinds of main pollutant parameters were collected from 9 important sections in the Guangzhou reach of the Pearl River from 1986 to 2000 and the water quality change was analyzed per time and space. The study concludes that the surface water quality of Guangzhou reflects ...  相似文献   
98.
Changes in concentration of polyamines in the developing mouse brain   总被引:3,自引:0,他引:3  
H Shimizu  Y Kakimoto  I Sano 《Nature》1965,207(5002):1196-1197
  相似文献   
99.
100.
计算机技术和多维坐标测量技术的迅速发展 ,使得坐标测量机被广泛地应用于各工业部门。本文提出了用坐标测量机测量渐开线圆柱齿轮齿形误差的想法 ,同时也提出了一种由计算机采集的数据计算齿轮齿形误差的方法  相似文献   
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