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排序方式: 共有1774条查询结果,搜索用时 281 毫秒
1.
Shinichi Takaichi 《Biotechnology letters》2014,36(6):1127-1128
General methods for identification of usual carotenoids including C18-HPLC retention time and spectroscopic methods, such as absorption spectra, mass spectra, NMR spectra, are briefly summarized. 相似文献
2.
Shinichi Nakamura Satoshi Nakashio Masato Mikawa Kiyotaka Yamakawa Seiichi Okumura Shoki Nishida 《Microbiology and immunology》1982,26(1):25-30
A total of 79 Clostridium difficile strains from healthy young and elderly adults, elderly patients without gastrointestinal disease, elderly patients receiving antibiotics without gastrointestinal complications, and elderly patients with antibiotic-associated diarrhea or pseudomembranous colitis were tested for their susceptibilities to 24 antimicrobial agents. All of the 79 strains were inhibited by low concentrations of rifampicin, metronidazole, fusidic acid, vancomycin, ampicillin, and penicillin G. The strains were highly resistant to aminoglycosides, trimethoprim, sulfamethoxazole, nalidixic acid, and cycloserine and often resistant to neomycin, cefoxitin, and cefalexin. Wide variations in the susceptibility of C. difficile strains to erythromycin, clindamycin, lincomycin, chloramphenicol, and tetracycline were found. Strains resistant to erythromycin, clindamycin, and lincomycin were more frequently found among strains isolated from elderly adults than those isolated from young adults, with particularly high frequency among strains isolated from elderly patients receiving antibiotics. None of the 23 strains isolated from healthy young adults was resistant to chloramphenicol. All of the 14 strains resistant to erythromycin, clindamycin, lincomycin, and chloramphenicol were sensitive to tetracycline and all of the 15 strains resistant to erythromycin, clindamycin, lincomycin, and tetracycline were sensitive to chloramphenicol. Only one out of 19 tetracycline-resistant strains was highly toxigenic, whereas 42 (70%) of 60 sensitive strains were highly toxigenic. 相似文献
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Intracellular quality control systems monitor protein conformational states. Irreversibly misfolded proteins are cleared through specialized degradation pathways. Their importance is underscored by numerous pathologies caused by aberrant proteins. In the cytosol, where most proteins are synthesized, quality control remains poorly understood. Stress-inducible chaperones and the 26S proteasome are known mediators but how their activities are linked is unclear. To better understand these mechanisms, a panel of model misfolded substrates was analyzed in detail. Surprisingly, their degradation occurs not in the cytosol but in the nucleus. Degradation is dependent on the E3 ubiquitin ligase San1p, known previously to direct the turnover of damaged nuclear proteins. A second E3 enzyme, Ubr1p, augments this activity but is insufficient by itself. San1p and Ubr1p are not required for nuclear import of substrates. Instead, the Hsp70 chaperone system is needed for efficient import and degradation. These data reveal a new function of the nucleus as a compartment central to the quality control of cytosolic proteins. 相似文献
5.
H. Ueda Takeshi Baba Nobuo Terada Yasuko Kato Shigeo Tsukahara Shinichi Ohno 《Histochemistry and cell biology》1997,108(3):243-248
It is known that the retina contains the protein dystrophin in the ribbon synapse, but the ultrastructural analysis is not
yet fully elucidated. Our previous study reported that dystrophin is localized under the rod cell membranes in rat retinas.
In the present study, we have investigated the relationship between dystrophin-rich regions of rod cell membranes and other
neuronal processes in mouse retinas with a monoclonal antibody raised against the human dystrophin C-terminus. Immunoblotting,
immunofluorescence stainings, and immunoelectron microscopy were employed. Immunoblotting analysis indicated that mouse retinas
possessed some of the dystrophin isoforms of approximately 260 kDa, 140 kDa, and 70 kDa molecular weight. Confocal images
showed a punctate appearance in the outer plexiform layer, as previously described. Immunoelectron microscopy showed that
dystrophin immunoreactive products were always observed at submembranous dense regions of the rod spherule abutting bipolar
processes. These results suggest that retinal dystrophin may be closely involved in signal transmission from rods to bipolar
cells.
Accepted: 7 May 1997 相似文献
6.
A Catechin‐rich Beverage Improves Obesity and Blood Glucose Control in Patients With Type 2 Diabetes
Tomonori Nagao Shinichi Meguro Tadashi Hase Kazuhiro Otsuka Masanori Komikado Ichiro Tokimitsu Takashi Yamamoto Kunio Yamamoto 《Obesity (Silver Spring, Md.)》2009,17(2):310-317
We investigated the effects of continuous ingestion of a catechin‐rich beverage in patients with type 2 diabetes who were not receiving insulin (Ins) therapy in a double‐blind controlled study. The participants ingested green tea containing either 582.8 mg of catechins (catechin group; n = 23) or 96.3 mg of catechins (control group; n = 20) per day for 12 weeks. At week 12, the decrease in waist circumference was significantly greater in the catechin group than in the control group. Adiponectin, which is negatively correlated with visceral adiposity, increased significantly only in the catechin group. Although the increase in Ins at week 12 was significantly greater in the catechin group than in the control group, no apparent difference was noted between the two groups in glucose and hemoglobin A1c. In patients treated with insulinotropic agents, the increase in Ins at week 12 was significantly greater in the catechin group than in the control group. This significant increase in Ins levels was observed only in the catechin group. In the catechin group receiving other treatments, Ins levels remained unchanged. In addition, in patients treated with insulinotropic agents, the decrease in hemoglobin A1c at week 12 was significantly greater in the catechin group than in the control group. These results suggest that a catechin‐rich beverage might have several therapeutic uses: in the prevention of obesity; in the recovery of Ins‐secretory ability; and, as a way to maintain low hemoglobin A1c levels in type 2 diabetic patients who do not yet require Ins therapy. 相似文献
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In occidental countries, the biodegradation of synthetic detergents has become one of the important problems in relation to the water quality protection programs. Their detergent industries are going to change active ingredient in detergent formulation from the non-biodegradable tetrapropylene-derived ABS (TBS) to the biodegradable Linear Alkylate Sulfonates (LAS). In our country, cesspools are served as domestic sewage disposal systems in very many homes, so that, it is necessary to observe the biodegradability of LAS in the cesspool. 相似文献
9.
Takayoshi Yamagishi Toshihiko Serikawa Ryoko Morita Shinichi Nakamura Shoki Nishida 《Microbiology and immunology》1976,20(5):397-403
TSN agar was applicable for enumeration of Clostridium perfringens in fecal samples of adults but not in those of infants. It was demonstrated using TSN agar that some healthy aged adults had persistently carried C. perfringens at levels ranging from 107 to 109, while some others ranged from 103 to 106 per ml volume of fecal sample although all of these adults had the same diets. In the test for agglutinability of isolates of C. perfringens collected from two elderly adults, a younger adult and a baby, it was demonstrated that most of the isolates obtained from an aged adult of high levels for 19 months belonged the same serotype, while rapid alteration of serotypes could be observed in three other persons with high or low levels. In spite of as many as 109 C. perfringens per ml of feces, no trace of α-toxin could be detected in the fecal samples. In in vitro tests, fecal suspension suppressed the production of α-toxin although it allowed the organism to grow sufficiently. 相似文献
10.
Haruhide Kawabe Hiroshi Naganawa Shinichi Kondo Hamao Umezawa Susumu Mitsuhashi 《Microbiology and immunology》1978,22(9):515-521
A clinical isolate of Staphylococcus aureus resistant to gentamicin, kanamycin and 3′,4′-dideoxykanamycin B contained two enzymes capable of inactivating gentamicin, i.e., an aminoglycoside 2″-phosphotransferase and aminoglycoside acetyltransferase. 相似文献