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101.
7起乙型脑炎疫苗异常反应的调查和分析   总被引:1,自引:0,他引:1  
对1993~1997年间因接种乙脑疫苗引起的7起异常反应进行了调查和分析,主要是Ⅰ型变态反应(0.33%~1.6%)和心因性反应(11.7%~24.2%)。反应一般发生在第3针以后,有些发生在第6针。症状表现为过敏性休克、紫癜、荨麻疹、血管神经性水肿、气喘等。对变态反应的发生频率、反应机理、处理方法和预防等问题进行了讨论  相似文献   
102.
Chicken embryonic retina is an excellent tool to study retinal development in higher vertebrates. Because of large size and external development, it is comparatively very easy to manipulate the chick embryonic retina using recombinant DNA/RNA technology. Electroporation of DNA/RNA constructs into the embryonic retina have a great advantage to study gene regulation in retinal stem/progenitor cells during retinal development. Different type of assays such as reporter gene assay, gene over-expression, gene knock down (shRNA) etc. can be performed using the electroporation technique. This video demonstrates targeted retinal injection and in ovo electroporation into the embryonic chick retina at the Hamburger and Hamilton stage 22-23, which is about embryonic day 4 (E4). Here we show a rapid and convenient in ovo electroporation technique whereby a plasmid DNA that expresses green fluorescent protein (GFP) as a marker is directly delivered into the chick embryonic subretinal space and followed by electric pulses to facilitate DNA uptake by retinal stem/progenitor cells. The new method of retinal injection and electroporation at E4 allows the visualization of all retinal cell types, including the late-born neurons1, which has been difficult with the conventional method of injection and electroporation at E1.52.  相似文献   
103.
Summary Occlusal intradentinal cavities, prepared in normal human premolars and third molars to be extracted for orthodontic reasons, were filled for 7 to 11 days with gutta percha. A superficial pulpitis with localized small abscesses developed in the pulp chamber. Under local anesthesia, 0.2 to 0.3 cc of sterile colloidal carbon was injected in the pulp horn and the teeth were extracted 1 to 3 h later. Lymphatic capillaries could thus be identified in the pulpal tissues. They were characterized by a thin endothelium with occasional large intercellular clefts, absence or incompleteness of basement membrane, absence of pericytes, absence of luminal red blood cells, and presence of a filamentous material between the endothelium and the surrounding collagen fibrils. Moreover, some structural variations were observed.  相似文献   
104.

Various methodical approaches for the discovery and selection of virus-resistant potato forms are analysed. The optimum methods and conditions of PVM, PVY and PVX plant inoculation by evaluation to immunity are revealed, a possibility of realisation of complex inoculations on Lycopersicon esculentum Mill. (cv Nevsky) infected by PVM + PVX mixture, what accelerates an evaluation and increases its efficiency. The necessity of the controlled infectious backgrounds creation by evaluation of potato selection material for field (relative resistance to PVM + PVY + PVX complex) is shown.  相似文献   
105.
Summary The effect of injections of ovine prolactin on kidney structure was examined in the first 10 days following transfer of seawater sticklebacks to fresh water.In hormone injected animals as well as in controls the glomeruli increase slightly in size after transfer. The podocytes intensify the secretion of mucopolysaccharides, which is indicative of increased turnover of the components of the glomerular basal lamina. The nuclei of the podocytes become enlarged, while those of the juxtaglomerular cells decrease in size. These changes are related to the well known rise of the glomerular filtration rate following transfer to fresh water. Structural indications that prolactin is involved in the control of glomerular filtration were not found.The epithelial cells of the three nephronic segments and of the ureter become considerably better developed after transfer to fresh water. Cell height, nuclear and mitochondrial volume, and surface of the membranes of the basal labyrinth increase in all tubular epithelia, although not to the same extent. Increases are moderate in the first proximal segment, but increasingly higher for the second proximal segment, collecting duct and the ureter. Especially the growth of membrane surface of the basal labyrinth, site of ion transport mechanisms, is impressive. In controls, values characteristic for freshwater fishes are reached in 6 to 9 days for all parameters for cellular development. Prolactin injections greatly stimulate growth rates in all tubular epithelia: freshwater values are reached within 3 days. No further increase was found, however.  相似文献   
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