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91.
92.
中国盲走螨属一新种和二新纪录:蜱螨亚纲:植绥螨科 总被引:1,自引:0,他引:1
本文记述我国植绥螨科盲走螨属Typhlodromus一新种和中国二新纪录:鲁盲走螨T.luensis sp.nov.,甲胄盲走螨T.lorcatus,肥厚盲走螨T.higoensis。标本保存于上海复旦大学环境和资源生物系。 相似文献
93.
Summary Plant hairy root cultures of Lithospermum erythrorhizon were carried out to produce shikonin derivatives by employing in situ extraction with n-hexadecane in a shake flask and a bubble column bioreactor. Over 95 % shikonin produced was recovered in the n-hexadecane layer. In flask cultures the maximum concentration of shikonin with n-hexadecane extraction was 3 times higher than that obtained without extraction. In the two phase bubble column reactor, 572.6 mg/L of shikonin and 15.6 g/L of dry cell mass were obtained after 54 days. Shikonin was produced at a constant level of 10.6 mg/L day during this period. 相似文献
94.
本文提取人骨骼肌α辅肌动蛋白(α-actinin)是综合了文献报导有关提取兔肌α-actinin的和提取鸡胗α-actinin的方法,稍加修改而确定的。用Hasselbach-Schneider缓冲液提取骨骼肌中的肌球蛋白后,将残余物经硼酸-缓冲液提取、匀浆及高速离心去掉肌动蛋白和肌原纤维的其它成份,上清加硫酸铵至30%,35%饱合度所得的沉淀用220mmol/LTris-乙酸溶解、透析、离心后经DE-52柱层析可得电泳纯。α-actinin。将人骨骼肌α-actinin纯化制品免疫了三只大耳白纯种家兔,两个多月后,三只兔子都产生免抗人骨骼肌α-actinin的特异抗血清,用双向免疫扩散法和酶联免疫吸附试验(ELISA)测定,产生的抗体效价较高,用双扩散法测定效价为1:32,用ELISA测定,用比率法判断结果,效价最高者为1:100,000左右,经免疫电镜观察结果证实,上述抗血清可以满足进一步实验要求。 相似文献
95.
本文报导了胰腺提取物中两种可被钙/钙调素依赖性蛋白激酶磷酸化的热稳定蛋白。SDS-PAGE测定其表观分子量分别为17.7kD和6kD。经钙/钙调素依赖性蛋白激酶磷酸化后,其最大磷酸参入量为8.8μmol/g蛋白。同时磷酸化作用导致17.7kD蛋白在SDS-PAGE中迁移率发生变化。本文还进一步分析了各种阳离子对磷酸化的影响,并对此两种蛋白可能具有的生理功能进行了初步探讨。 相似文献
96.
We have characterized, by electron probe microanalysis, rapidly frozen cultured rat islets at the level of individual secretory granules. Elemental analysis of thin, dried cryosections showed that beta granules could be distinguished by high Zn, Ca, and S, whereas non-beta (mainly alpha) granules contained elevated P and Mg. Although a single granule type predominated in a particular cell, some rebel granules were found in A cells that had the compositional fingerprint of B cell granules. Zn, which was found in millimolar concentrations in B cell granules, was considered a marker for the insulin storage complex. The data indicate that non-B islet cells in the adult pancreas may produce insulin-containing organelles and that, when glucagon and insulin are coexpressed, these hormones are packaged in separate granules. 相似文献
97.
98.
Masato Maekawa Kayoko Sudo Masato Kitajima Yukio Matsuura Steven S.-L. Li Takashi Kanno 《Human genetics》1993,92(2):163-168
In northwest European countries maternal age is increasing. This will lead to an increase of the prevalence of Down syndrome conceptuses. Meanwhile, the increased use of prenatal cytogenetic diagnosis (PCD) will lead to a decrease in the prevalence of Down syndrome among livebirths. We were interested to know what the result of these two opposite developments would be in the near future, and we describe here a model to quantify these processes and the resulting livebirth prevalence of Down syndrome. The model is demonstrated for The Netherlands from 1992 to 2001. The predicted livebirth prevalence for The Netherlands in 1992 is 1.36 per 1000. Demographic factors will cause an increase to 1.76 per 1000 in 2001 with present indications for PCD and a utilization ratio of 50%. An increase of the utilization ratio to 90% in 2001 will lead to a prevalence of 1.22 per 1000, a little less than the present prevalence. Alternative screening programs, including maternal serum screening, could lead to a further decrease of the livebirth prevalence. The model described here can be used for evaluation of the consequences of alternative forms of Down syndrome screening. 相似文献
99.
应用纤维连接素(Fn)、S—100蛋白、胶质纤维酸性蛋白(GFAP)、细胞角蛋白(CK)和神经特异性烯醇蛋白(NSE)5种抗体对63例正常人垂体前叶内滤泡星状细胞(FSC)进行了免疫细胞化学研究。结果表明:人FSC内26.9%S_(100)阳性,9.3%GFAP阳性,63.8%两者都为阳性。CK、NSE和Fn均为阳性。从而提示了FSC来自神经外胚层的原始细胞而非Rathke's囊上皮的残留。 相似文献
100.
Cheng Jianxin Xia Yuqing Zhou Cheng Li Xiaohao Liu Pengfei 《Marine biotechnology (New York, N.Y.)》2023,25(2):291-313
Marine Biotechnology - Takifugu rubripes is important commercially fish species in China and it is under serious threat from white spot disease (cyptocaryoniasis), which leads to heavy economic... 相似文献