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91.
流行性出血热地鼠肾细胞灭活疫苗人体试用细胞免疫反应观察 总被引:2,自引:0,他引:2
观察了20位志愿者在接种试验性流行性出血热(EHF)地鼠肾细胞(GHKC)双价灭活疫苗后的细胞免疫反应,并以其体液免疫反应作对照观察。用淋巴细胞转化试验测定细胞免疫水平。结果首针疫苗接种后42天和56天,特异性刺激指数(SSI)和非特异性刺激指数(NSI)均较免疫前显著增高(P_(SSI)<0.001;P_(NSI)<0.02),免疫后SSI累计阳转率为100%,NSI累计阳转率为60%,免疫后6个月二者均降低至正常水平。免疫后56天测定抗体,荧光抗体阳转率为100%;微量感染性中和试验表明,针对家鼠型病毒L99株中和抗体阳转率为95%,而针对野鼠型病毒JR株阳转率为65%。 相似文献
92.
从浙江产蝮蛇毒中分离出一种凝血酶样酶,该酶能明显地延长全血凝固时间,白陶土部分凝血活酶时间(KPTT),并降低了血浆中的纤维蛋白原水平,同时全血的比粘度和血浆的比粘度及血清中的胆固醇和β脂蛋白均有所下降.该酶不激活凝血因子ⅩⅢ. 相似文献
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94.
Cloning and structural analysis of cDNA and the gene for mouse transcription factor UBF 总被引:21,自引:7,他引:14 下载免费PDF全文
K Hisatake T Nishimura Y Maeda K Hanada C Z Song M Muramatsu 《Nucleic acids research》1991,19(17):4631-4637
95.
Cold shock and heat shock: a comparison of the protection generated by brief pretreatment at less severe temperatures 总被引:1,自引:0,他引:1
Abstract Brief exposure to low (0o C) or high (40o C) temperature elicits a protective response that prevents injury when the flesh fly, Sarcophaga crassipalpis Macquart, is subjected to more severe cold (-10o C) or heat (45o C). Both the low and high temperature responses were found in all developmental stages of the fly, but were most pronounced in the pupal and pharate adult stages. The protective responses generated by brief exposure to 0 or 40o C appear similar in that both result in a rapid acquisition of cold or heat tolerance and a loss of protection after the flies are returned to 25o C. The protection generated by chilling is obvious within 10 min of exposure to 0o C while a 30 min exposure to 40o C is required to induce the high temperature protection. High temperature protects against cold shock injury within a narrow range (around 36o C) but we have no evidence that low temperature can protect against heat injury. We previously demonstrated that the rapid increase in cold tolerance correlates with concomitant increases in glycerol concentration, but in this study we found no significant elevation in glycerol in heat-shocked flies. Thus the physiological and biochemical bases for the rapid responses to cold and heat appear to be different. 相似文献
96.
The effect of fluorosis on lactation, lactotroph function and ultrastructure were studied in lactating rats. The results were as follows: 1) Inhibition of lactation in lactating rats with chronic fluorosis was assessed by stunting growth of pups and decrease in the amount of milk suckled by pups in 30 min. Metoclopramide, a blocker of dopamine receptor, could improve lactation in these rats. 2) During chronic fluorosis serum PRL level was decreased, however, PRL content in pituitary was increased. Electronmicroscopic examination showed accumulation of large mature secretory granules and appearance of extremely large abnormal secretory granules in lactotroph cytoplasma. These findings indicate that hormone release of pituitary lactotrophs is obstructed in lactating rats with fluorosis, and the toxic effect of fluoride is mediated by an enhanced function of dopaminergic system in hypothalamus. 相似文献
97.
本文在麻醉并制动的大鼠上观察了中缝背核(DR)条件刺激对由苔状和爬行纤维传入引起的小脑浦肯野细胞(PC)诱发反应的影响。主要结果有:(1)刺激大脑皮层感觉运动区可以引起苔状和爬行纤维向对侧小脑皮层第Ⅵ和Ⅶ小叶的传入,因而在该小叶上记录到 PC 的诱发简单锋电位(SS)和复杂锋电位(CS)反应,潜伏期分别是8—25和12—30ms。(2)以不影响PC 自发 SS 和 CS 活动的阈下强度刺激 DR,可显著地压抑 PC 对于刺激感觉运动皮层引起的苔状和爬行纤维兴奋所产生的诱发 SS 和 CS 反应,这种压抑作用可持续数百毫秒。(3)DR条件刺激对 PC 的诱发 SS 和 CS 反应的压抑作用可以被静脉注射5-HT 受体阻断剂羟甲丙基甲基麦角酰胺所减弱或阻断。上述结果表明 DR 的5-HT 能纤维传入可以降低苔状和爬行纤维对 PC 的突触作用效力,抑或降低 PC 对突触传入的反应敏感性,提示中缝-小脑5-HT,能纤维传入系统参与了小脑某些重要的神经活动过程。 相似文献
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100.
A single wheatgrass chromosome reduces the concentration of barley yellow dwarf virus in wheat 总被引:3,自引:0,他引:3
R. I. S. BRETTELL P. M. BANKS Y. CAUDERON X. CHEN Z. M. CHENG P. J. LARKIN P. M. WATERHOUSE 《The Annals of applied biology》1988,113(3):599-603
Seedlings of a series of addition or substitution lines of wheat containing different Thinopyrum intermedium chromosomes were inoculated with the PAV and RPV serotypes of barley yellow dwarf virus (BYDV). Reduced virus titres in infected plants were ascribed to a single pair of homoeologous group 7 chromosomes from Th. intermedium in the disomic addition lines L1 and TAF 2. The group 7 chromosome is associated with red pigmentation of coleoptiles, which was also observed in two lines ditelosomic for the α arm of the chromosome. However, when infected with the PAV serotype of BYDV, the ditelosomic lines had normal virus titres and it is concluded that potential determinants of BYDV resistance are located on the β arm of the Group 7 chromosome. 相似文献