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21.
抗人生长激素免疫血清的制备和鉴定 总被引:1,自引:1,他引:0
Using small dosage of human growth hormone to immunize rabbit or guinea pig, it is able to induce anti-hGH antibody formation with high titre and high affinity that could be applied to hGH RIA. In the present study five rabbits and three guinea pigs were immunized with 125-200 micrograms and 250-285 micrograms per animal of hGH respectively, followed by boosters of 10-20 or 160-250 micrograms of hGH at 2-4 week intervals for 6 or 3 months. Blood was drown 1-2 weeks before each booster for determination of antibody formation. Antibody titre and affinity were successively observed and specificity of antibody was determined for the final bleeding. It was shown that titres of immune sera from guinea pigs were much higher than those of rabbit immune sera, but vice versa for antibody affinity. This might be due to larger immunogen dose used for guinea pigs than for rabbits. Fourteen different peptide hormones were tested in reference to cross-immunoreactivity to anti-hGH antibody. It could be demonstrated that the major cross-reactive hormones are hFSH and hLH, and hTSH also reacts to rabbit anti-hGH immune sera at a lesser degree. These cross reactivities are obviously owing to the molecular homogeneities between hGH and these hormones especially of their alpha-subunits. 相似文献
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M D'Incalci G Balconi M Broggini T Colombo M Marzola F Morali Y Pang S Sen L Spinelli 《Cancer surveys》1989,8(3):535-555
Theoretically, two predominant paths for obtaining more selective anticancer agents may be envisaged. These are: (a) to make compounds which distribute only or preferentially in cancer cells; (b) to make compounds that are able selectively to kill or to differentiate cancer cells. Although in the last two decades research into new anticancer drugs has not produced satisfactory results, there is solid ground on which novel strategies can be developed, mainly based on a much greater biological knowledge of human tumours. This article does not review all the possible approaches that may be followed, but simply discusses some ideas and problems mainly taken from the current research of our laboratory. 相似文献
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本文描述了奇特长唇瓢虫Shiro(?)lla mirol(?)ilis Sasaji的雄性外生殖器与本属两新种:附肢长唇瓢虫Sh.oppe(?)nd(?)a sp.n.,阿里山长唇瓢虫Sh.(?) sp.n.,均产于台湾.种类检索如下:1(2).后基线伸达第一腹板1/2略强:阳基侧叶长,无触须状附肢;鞘翅淡黄棕色,具七个黑色斑纹;体 长1.82 mm………………………………………………………阿里山长唇瓢虫Sh.(?)sp.n.2(1).后基线后缘远超第一腹板长度的1/2;阳基侧叶短,具触须状附肢:3(4).前胸背板棕色,具两个暗棕色模糊斑点;鞘翅棕色,具九个黑斑;体长2.12~2.59 m………… …………………………………………………………………………附肢长唇瓢虫Sh.(?)sp.n.4(3).前胸背板淡黄棕色,无斑点;鞘翅淡黄棕色,具六个黑斑,侧面的一对长形;体长2.00~2.26mm …………………………………………………………………………奇特长唇瓢虫Sh.(?)sasaji 相似文献
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The sperm penetration assay is an expensive, time-consuming test to assess male fertility in vitro. Although some investigators are enthusiastic in its application, others feel that it is not sensitive or specific enough to be used as part of the routine infertility evaluation. Indeed, this bioassay is not a faithful reproduction of in vivo conditions. However, if the SPA is abnormal, it is unlikely that sperm will fertilize a human ovum in vivo. Conversely, a normal SPA does not guarantee successful in vivo fertilization. No bioassay can be absolute in its predictive value, but false-negative results must be kept to a minimum for this bioassay to be of any clinical significance. Each laboratory performing the SPA should optimize the assay for sensitivity, reproducibility, and minimization of false-negative results and then establish normal and abnormal ranges of its own. If the limitations of the SPA are kept in mind, and if we employ it very selectively, it may still be useful. 相似文献
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The empty sella syndrome is common in middle-aged women, usually presenting with headache, and only occasionally associated with endocrine or visual abnormalities. It is rare in childhood. Childhood cases tend to present either with endocrine disturbances, visual symptoms, or with craniofacial syndromes. We present three cases of complete empty sella with childhood onset, each discovered unexpectedly during evaluation of endocrine or visual dysfunction. 相似文献
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目的探讨广东地区宫颈癌组织中HPV16肿瘤相关性抗原E7基因序列的多态性.方法采用通用引物PCR直接测序法对宫颈癌标本中的HPV分型,从含有HPV16型的标本中采用自行设计的多重引物通过巢式PCR扩增出HPV16E7,经DNA序列测定法检测其基因变异,进而寻找其热点突变.结果50例宫颈癌组织HPV-DNA的检出率为78%,其中HPV16和HPV18型混合感染18例,单纯HPV16型感染15例.33例含有HPV16型的标本中扩增出25例HPV16E7,其中17例647位核苷酸“T”变异“C”,导致相应的蛋白质由天冬氨酸变异为丝氨酸.结论广东地区宫颈癌组织中HPV16E7DNA序列发生碱基替换的区域主要在647位至846位,热点突变点为Nt647和Nt846. 相似文献