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排序方式: 共有901条查询结果,搜索用时 15 毫秒
891.
Shinichi Nakamura Masato Mikawa Satoshi Nakashio Manabu Takabatake Imiko Okado Kiyotaka Yamakawa Toshihiko Serikawa Seiichi Okumura Shoki Nishida 《Microbiology and immunology》1981,25(4):345-351
Attempts were made to isolate Clostridium difficile from a total of 431 fecal specimens from 149 young and 213 elderly healthy adults, and 69 elderly adults with cerebrovascular disease but no gastrointestinal disease. C. difficile was isolated from 49 specimens, and the frequency of isolation was 15.4% in healthy young adults, 7.0% in healthy elderly adults, and 15.9% in elderly adults with cerebrovascular disease. Thirty-four (about 70%) of the 49 C. difficile strains isolated produced cytotoxin which was neutralized by Clostridium sordellii antitoxin in vitro; in both young and elderly adults approximately 30% of the C. difficile isolates were nontoxigenic. The mean concentration of C. difficile in feces was 104.1/g in young adults and 104.6/g in elderly adults, with a range of 102.0 to 106.9/g. Antibody against C. difficile toxin was found in most of the sera obtained from young adults carrying toxigenic C. difficile, but not in sera of elderly adults, no matter how abundant was toxigenic C. difficile in the feces. 相似文献
892.
893.
We isolated mutants whose vaccinia hemagglutinin (HA) accumulates on nuclear envelopes and the rough endoplasmic reticulum. Mutant HA must be blocked at a pre-Golgi step because it has high-mannose-type carbohydrates but no fucose. Neither N- nor O-glycosidically linked carbohydrates are involved in the transport defect of the mutant HA, because tunicamycin, an inhibitor of N-type glycosylation, has no effect, and O-type glycosylation takes place in the Golgi organelle. The unglycosylated form of the mutant HA synthesized in the presence of tunicamycin is 3000 daltons larger than the wild type. This higher molecular weight is related to the transport defect. HAs translated in vitro also show this difference, evidence that it reflects mutation in the HA structural gene. Portions of HAs that project into the cytoplasm seem to account for this weight difference. Thus the cytoplasmic tail of glycoprotein has an important function in transport out of the rough endoplasmic reticulum. 相似文献
894.
895.
896.
Shigeki Sawayama Seiichi Inoue Kenichiro Tsukahara Tatsuo Yagishita 《Biotechnology letters》2001,23(3):195-199
Phototrophic bacterial cells in the effluent from a lighted upflow anaerobic sludge blanket reactor supplied with a medium containing 142 mg S (as SO4
2–) l–1 accumulated a 6.8% w/w oleic acid content in cells and 19 mg cell-bound oleic acid l–1 in the effluent. Pure cultures of Rhodopseudomonas palustris and Blastochloris sulfoviridis isolated from the effluent also accumulated 5.1 and 6.4% w/w oleic acid contents in cells, respectively. The oleic acid content in the cells recovered from the LUASB reactor effluent was related to the phototrophic bacterial population in the LUASB reactor. The inverse relationship was observed in the LUASB reactor between phototrophic bacterial growth and sulfate concentration in the influent. 相似文献
897.
898.
Noboru Oriuchi Naoyuki Watanabe Hidetoshi Kanda Makoto Hashimoto Sumio Sugiyama Seiichi Takenoshita Kyouichi Imai Ryuzou Ueda K. Endo 《Cancer immunology, immunotherapy : CII》1998,46(6):311-317
The study was designed to clarify the difference in pharmacokinetics of monoclonal antibodies (mAb) in animal models and
humans, and to elucidate the applicability of animal models. 99mTc-labeled murine mAb – against carcinoembryonic antigen (designated BW431/26), and neural cell adhesion molecule (NE150)
– and one chimeric mouse/human mAb against nonspecific cross-reacting antigen (chNCA) were administered i.v. to normal mice
and athymic mice (370 kBq, 400 ng) xenografted with human cancer cells expressing antigens, and into patients with tumor (925
MBq, 1 mg). The biodistribution of two of the three mAb (not 99mTc-BW431/26) differed clearly in mice and patients. 99mTc-NE150 showed specific uptake in xenografted tumor and otherwise a normal biodistribution; however, clinical examination
showed increased uptake in the liver with rapid blood clearance (mean α half-life = 31.1 min) compared with 99mTc-BW431/26 (28.4 h). 99mTc-chNCA demonstrated increased blood clearance and renal excretion in both normal and athymic mice, with accumulation in
tumors. Clinical examination showed rapid blood clearance (mean α half-life = 6.4 min) and increased uptake in the liver.
High-performance liquid chromatographic analysis of 99mTc-chNCA revealed the immune complex in blood, suggesting uptake of the complex by the reticuloendothelial cells. The biodistribution
of radiolabeled mAb in animal and human models was variable and specific for each of the three mAb. The results of animal
studies with mAb should be evaluated carefully before being extrapolated to humans, on the basis of the nature of the mAb
and interacting substances.
Received: 9 April 1997 / Accepted 3 March 1998 相似文献
899.
900.
Genetica - Recently, anthropogenic alterations have had severe and negative impacts on the terrestrial and aquatic species and environments. To conserve species that have a small and limited... 相似文献