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41.
Different characteristic damages of the SGC-7901 gastric adenocarcinoma cells were studied by electron microscopy 1, 36, 72, 96 and 120 hours after heating and radiation in vitro. The visible damages, such as the enlarged mitochondria, increase of lysosomes and perichromatin granules could be shown 1 hour after heating (43 degrees C for 30 min) but no visible damages of the cells were shown until 36 hours following radiation (500 rad). In order to study the ultrastructural changes of the gastric cancer cells in mitosis after heating and radiation, we have used the new method of ultrastructural research in selecting and observing the M cell in vitro and found loosened structure of chromosome and disappearance of microtubules 1 hour following hyperthermia. At the same time, no apparent abnormalities of the mitotic cells were observed after radiation. It is the chief cause of division delay in heat injured cells. However, the chromosomes and microtubules of the new mitotic cells could recover 36 hours after heating (43 degrees C for 30 min). After radiation, the giant cells and abnormal morphologic changes of cells gradually increase and the living cells decrease. Unexpectedly, the division of a few giant cells is observed 72 hours after heating and radiation.  相似文献   
42.
小学生吸烟行为健康教育干预实验   总被引:4,自引:2,他引:2  
本文报告了自1991年以来在四川省什邡县所进行的小学生吸烟行为健康教育干预实验。结果显示,实验达到了预期目的。根据基线调查资料对对象儿童吸烟行为影响因素所作的分析以及在此基础上所采取的干预策略是正确的,干预方法是有效的。从而证明了在一个成人吸烟占主流的社会环境中通过健康教育劝阻儿童吸烟尽管是很困难的,但却是完全有成功把握的。  相似文献   
43.
Many previous studies have implicated cell surface saccharides, and sialylglycoconjugates in particular, as important mediators of tumor cell metastasis. In this report, we have used three different specific sialidases and a highly sensitive high-performance liquid chromatographic sialic acid assay to probe the cell surfaces of several murine adrenal carcinoma variants. In contrast to several earlier studies on other metastatic variants, we find no significant differences in the overall levels of cell surface or total cellular sialic acid among three Y1 murine adrenal carcinoma variants with widely different metastatic phenotypes. However, using highly purified, linkage-specific sialyltransferases, in conjunction with V. cholerae sialidase, to probe the cell surface saccharide topography of specific penultimate oligosaccharides, we do find striking differences in oligosaccharide structures underlying the sialic acid moieties. Two tumorigenic and metastatic variants (F2 and F4) contain about 6-fold more penultimate Gal beta 1----4GlcNAc sialylation sites than a related tumorigenic but nonmetastatic variant (HSR) when CMP-[3H]-N-acetylneuraminic acid and the Gal beta 1----4GlcNAc alpha 2,6 sialyltransferase are used to probe the adrenal carcinoma cell surfaces. The metastatic variants also are found to contain 4- to 4.5-fold more Gal beta 1----3GalNAc sialylation sites than the nonmetastatic variant when the Gal beta 1----3GalNAc alpha 2,3 sialyltransferase is used as a cell surface probe. Earlier work, which used the same sialyltransferase probes on sialidase-treated murine melanoma variants (A. Passaniti and G. W. Hart, J. Biol. Chem., 263: 7591-7603, 1988), also showed similar quantitative differences in penultimate structures between metastatic variants. However, in contrast to the adrenal carcinoma cells, the highly metastatic melanoma cells have severalfold lower levels of sialylatable penultimate Gal beta 1----4GlcNAc and Gal beta 1----3GalNAc saccharides compared to their nonmetastatic counterparts. Thus, while the precise structural alterations or surface accessibilities of penultimate saccharides appear to be cell type dependent, these results suggest that pronounced changes in penultimate cell surface sialo-oligosaccharide moieties occur during progression to a malignant phenotype in two widely different tumor systems. These types of alterations in the underlying penultimate oligosaccharide structures of cell surface sialoglycoconjugates may be a common feature of highly metastatic cells arising from very different tumor cell types.  相似文献   
44.
多发性肌炎与皮肌炎25例,其中多发性肌炎21例,皮肌炎2例,多发性肌炎或皮肌炎伴发恶性肿瘤2例。从临床表现、生化检查、肌电图及肌肉活检等方面进行分析,提出多发性肌炎与皮肌炎的诊断条件。本组均采用皮质类固醇治疗,5例合并免疫抑制剂治疗,其中临床治愈4例,显著好转10例,好转5例,无效2例,死亡4例。  相似文献   
45.
诺氟沙星的吸附伏安法研究   总被引:5,自引:0,他引:5  
在pH=7.49氨-氯化铵缓冲液中,诺氟沙星在滴汞电极上产生一灵敏的还原峰,峰电位为-1.52V(vs.SCE)。在1.98×10(-7)~4.88×10(-6)mol/L之间有良好的线性关系。本文对其极谱性质和电极过程进行了研究,用于诺氟沙星的测定,方法简便,结果准确、可靠。  相似文献   
46.
SM6是我国检测E1Tor霍乱弧菌是否带有溶源性噬菌体的指示菌株。江苏的6株E1Tor霍乱弧菌和SM6都属于噬菌体-生物分型的1d型,而在噬菌体分型中SM6为1/2型,江苏的6株菌株则为1/2/3型;霍乱毒素(CT)基因测定也表明两者的不同,SM6不含CT基因,江苏的6株都含有CT基因,显示噬菌体分型可将噬菌体-生物分型的型别进一步划分,SM6的特性也为霍乱的进一步研究提供了资料。  相似文献   
47.
为了探讨彩色多普勒血流显像技术显示正常人睾丸内血流的可行性,并探讨睾丸的血流动力学特征,我们对20名正常人双侧睾丸进行了彩色多普勒检查。结果显示,彩色多普勒能显示所有睾丸的包膜动脉、向心动脉。正常睾丸的包膜动脉和向心动脉收缩期峰值血流速度的均值分别为9.00cm/s和7.42cm/s;舒张末期血流速度均值分别为3.50cm/s和3.38cm/3,本文对睾丸彩色血流显像和多普勒频谱特点也作了讨论。  相似文献   
48.
Summary Effects of Chinese Medicinal Preparation “Re Du Qing” (RDQ) on the activation, proliferation and membrane fluidity of T lymphocytes from human peripheral blood Were studied by means of3H-TdR incorporation and DPH fluorescence polarization. The results showed that “RDQ” can:1) significantly inhibit the activation of T lymphocytes; 2) restrain the proliferation of activated T lymphoblasts in the presence of exogenous interleukin-2 (IL-2); and 3) increase the membrane fluidity of T lymphocytes and antagonize the decreased fluidity of lymphocyte membrane mediated by Con A or PHA. The functional abnormalities of T lymphocytes in some autoimmune diseases such as arthritis and the usefulness of RDQ in the treatment of these diseases were also discussed.  相似文献   
49.
中国饮用水源水中藻类卫生标准的研究   总被引:17,自引:0,他引:17  
施玮  蒋颂辉  朱惠刚 《卫生研究》2003,32(2):97-100
为制定饮用水源中藻类限值 ,结合国内外文献调查研究毒理学试验和现场生态学调查资料 ,根据世界卫生组织 (WHO)和卫生部推荐的饮用水中微囊藻毒素MC -LR的限值、藻类生物量和MC -LR浓度关系以及毒理学实验所得到的藻类的无作用浓度而制定饮用水源中藻类限值。结果显示 ,推荐饮用水源中藻类三级限值分别为 :安全限值 :1.0× 10 4个 升 ;警戒限值 :2 .1× 10 5个 升 ;危险限值 :1.2× 10 6 个 升。提示饮用水源中藻类限值在日常工作中有显著意义和可行性  相似文献   
50.
A case of severe hemophilia A was treated by living mother-to-son splenic transplantation. The recipient was a 9-year-old boy. After splenic transplantation, the level of blood factor VIII:C was increased, and no spontaneous hemorrhage occurred. The boy was followed up for over two years. This is a case of spleen allotransplantation with the longest function in the world.
  相似文献   
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