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排序方式: 共有511条查询结果,搜索用时 15 毫秒
1.
目的:分离鉴定鹿茸中神经节苷脂的成分。方法:Folsh分配、DEAE-Cellulose柱层析分离、薄层色谱方法鉴定。结果:分离鉴定出3种组分(A、B、C),与对照品薄层图谱对照,鉴定了A为GM4,B为GM3,C为GD3,A、B、C的百分含量分别为24.4%、46.2%、29.4%。结论:首次从鹿茸中分离出GM4,GM3,GD33种神经节苷脂成分。 相似文献
2.
用双向电泳分析淡色库蚊卵、二令幼虫、四令幼虫、蛹和成虫蛋白质组成.电泳完毕后,用考马斯亮兰G-250染色,结果以成蚊蛋白质多肽点为最多(116点),其次依次为蛹(101点)、卵(70点)、四令幼虫(53点)、二令幼虫(18点)。它们在不同分子量和不同PH 范围内的分布也不同,但总的来看,在幼体阶段(卵、二、四令幼虫及蛹)多偏低分子量和低PI 值的点,发育至成虫阶段,分布走向全面。 相似文献
3.
鹿茸有效成分对小鼠肝脏RNA和蛋白质合成的影响 总被引:1,自引:0,他引:1
多次给小鼠po鹿茸多胺30mg/kg,对[3H]leucine和[3H]uridine掺入肝组织蛋白和RNA有明显的促进作用,而庸茸非多胺则无此作用;当腐胺剂量为21mg/kg时,不仅促进[3H]leucine和[3H]uridiae掺入肝组织蛋白和RNA,也促进[3H]uridine掺入肝细胞核的RNA中,并增强RNA聚合酶的活性;精脒在剂量为8mg/kg时,仅对[3H]leucine掺入肝组织蛋白有促进;而精胺在1mg/kg时,没有观察到上述各种现象。此结果提示,鹿茸多胺类物质是鹿茸中刺激小鼠肝组织蛋白和RNA合成的主要活性物质,这
种刺激小鼠肝组织蛋白和RNA合成效应是由于鹿茸多胺能够显著地增强RNA聚合酶的活性。 相似文献
4.
FIONA TOMLEY 《Parasite immunology》1994,16(8):407-413
Total polypeptides from unsporulated and sporulated oocysts, sporozoites and the first two generations of merozoites of Eimeria tenella were fractionated by electrophoresis through polyacrylamide gels. The parasites are complex and the arrays of polypeptides differ for each of the developmental stages indicating that there is stagespecific control of gene expression. In particular, first generation merozoites display a markedly different polypeptide profile to that of either sporozoites or second generation merozoites. Changes in antigenicity during sporulation and the antigenic relationships between the three asexual zoite stages were examined by probing electroblotted polypeptides with a panel of antisera raised in rabbits to purified preparations of each stage. Antigenic cross-reactivity is well maintained throughout sporulation even though the sizes of antibody-reactive polypeptides change. In contrast there is a marked lack of cross-reactive epitopes between sporozoites, first and second generation merozoites. 相似文献
5.
6.
鹿茸生长素对家兔关节软骨细胞代谢的影响 总被引:3,自引:0,他引:3
目的 研究鹿茸生长素对关节软骨细胞增殖的影响。方法 采用家兔关节软骨细胞体外培养和加入同位素3H—TdR标记方法,观察其对3H—TdR掺入细胞DNA合成的影响。结果 加入鹿茸生长素组的3H—TdR的掺入值与对照组有明显差异,细胞增殖作用明显。结论 鹿茸生长素能明显刺激关节软骨细胞的增殖。 相似文献
7.
Terry M. Maloney Philip L. Paine Jose Russo 《Breast cancer research and treatment》1989,14(3):337-348
Summary The protein populations of epithelial cells cultured from two neoplastic and five non-neoplastic human breast tissues were resolved and displayed by two-dimensional polyacrylamide gel electrophoresis and silverstaining. With a computer-based image analysis system, we identified eight polypeptides which are present in both of the neoplastic cell lines, but absent from all five of the cultures of non-neoplastic breast cells. The eight polypeptides are not unique to cells cultured from neoplastic breast, because they are also found in cells cultured from non-breast tissues, both neoplastic and non-neoplastic. Two of the eight polypeptides ( Mr 25,000/pI 4.4 and Mr 31,000/pI 5.5) are present in the patterns of whole tissue samples from infiltrating ductal carcinomas and absent in most normal breast tissue. 相似文献
8.
Immunoprecipitation of radiolabeled polypeptides from complex mixtures of proteins was performed in polystyrene microtiter plates using staphylococcus protein A and various antibody preparations. The method is (1) rapid, (2) uses multichannel micropipettor technology, (3) handles large numbers of specimen easily, (4) requires very small volumes of antigen and antibody (5–50 μl), (5) provides replicates for statistical analysis and (6) allows recovery of precipitated proteins for direct SDS-PAGE analysis of precipitated proteins. We have shown it is useful as a test to screen large numbers of sera or to characterize monoclonal antibody-containing samples. 相似文献
9.
Barry Gusterson Diana Mitchell Michael Warburton John Sloane 《Virchows Archiv : an international journal of pathology》1982,394(3):269-277
Summary Antisera against total keratin extracts of human callus have been used to identify keratins in lung tumours of different histological type. Forty-three were classified by the WHO scheme. Keratin immunoreactive cells were identified in all 8 epidermoid carcinomas; 6 out of 12 large cell carcinomas; 2 out of 6 adenocarcinomas; 2 out of 15 small cell carcinomas and in the only muco-epidermoid carcinoma. These cases demonstrate the heterogeneity of phenotypic expression in lung tumours not recognisable without the use of immunohistochemical techniques. 相似文献
10.
Adhesion polypeptides are useful for the prevention of peritoneal dissemination of gastric cancer 总被引:3,自引:0,他引:3
Tasuku Matsuoka Kosei Hirakawa-YS Chung Masakazu Yashiro Shigehiko Nishimura Tetsuji Sawada Ikuo Saiki Michio Sowa 《Clinical & experimental metastasis》1998,16(4):381-388
We examined the effect of adhesion polypeptides on the adhesion and invasiveness of gastric cancer cell lines. We previously reported the establishment of an extensively peritoneal-seeding cell line, OCUM-2MD3, from a poorly seeding human scirrhous gastric carcinoma cell line, OCUM-2M. Both 21 and 31 integrin expression was markedly increased on OCUM-2MD3 cells compared with OCUM-2M cells, and the ability of OCUM-2MD3 cells to bind to the extracellular matrix (ECM) was also significantly higher than that of OCUM-2M cells. The adhesion polypeptides, YIGSR and RGD, and two RGD derivatives significantly inhibited the adhesion of OCUM-2MD3 cells to the submesothelial ECM, while not inhibiting the adhesiveness of OCUM-2M cells and two well differentiated human gastric cell lines, MKN-28 and MKN-74. The YIGSR and RGD peptides also significantly inhibited the invasiveness of OCUM-2MD3 cells. The survival of nude mice with peritoneal dissemination given YIGSR sequenc e intraperitoneally was obviously longer than that of untreated mice. The survival of mice treated with RGD was also improved, and this effect was increased using the RGD derivatives, poly(CEMA-RGDS) and CM-chitin RGDS. These polypeptides appear to block the binding of integrins, which are expressed on OCUM-2MD3 cells, to the submesothelial ECM, and consequently inhibit peritoneal implantation. The peritoneal injection of adhe-sion polypeptides may be a new therapy against the dissemination of scirrhous gastric cancer, and may be useful for the prevention of dissemination in high-risk patients. © Rapid Science Ltd. 相似文献