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排序方式: 共有3707条查询结果,搜索用时 46 毫秒
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Koizumi Noriyuki Hanamura Yukio Nishida Kazuya Mori Atsushi Watabe Keiji Takemura Takeshi Man Alias Kassim Faizul M. Morioka Shinsuke 《Conservation Genetics Resources》2015,7(1):133-135
Conservation Genetics Resources - We have developed microsatellite DNA markers for Mesopodopsis orientalis (Tattersall 1908), a widely distributed mysid crustacean in shallow waters of the coastal... 相似文献
85.
Comparison of clinical characteristics in patients with type 2 diabetes among whom different antihyperglycemic agents were prescribed as monotherapy or combination therapy by diabetes specialists 下载免费PDF全文
86.
Glycine residues in potassium channel-like selectivity filters determine potassium selectivity in four-loop-per-subunit HKT transporters from plants 总被引:16,自引:0,他引:16
Mäser P Hosoo Y Goshima S Horie T Eckelman B Yamada K Yoshida K Bakker EP Shinmyo A Oiki S Schroeder JI Uozumi N 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(9):6428-6433
Plant HKT proteins comprise a family of cation transporters together with prokaryotic KtrB, TrkH, and KdpA transporter subunits and fungal Trk proteins. These transporters contain four loop domains in one polypeptide with a proposed distant homology to K(+) channel selectivity filters. Functional expression in yeast and Xenopus oocytes revealed that wheat HKT1 mediates Na(+)-coupled K(+) transport. Arabidopsis AtHKT1, however, transports only Na(+) in eukaryotic expression systems. To understand the molecular basis of this difference we constructed a series of AtHKT1/HKT1 chimeras and introduced point mutations to AtHKT1 and wheat HKT1 at positions predicted to be critical for K(+) selectivity. A single-point mutation, Ser-68 to glycine, was sufficient to restore K(+) permeability to AtHKT1. The reverse mutation in HKT1, Gly-91 to serine, abrogated K(+) permeability. This glycine in P-loop A of AtHKT1 and HKT1 can be modeled as the first glycine of the K(+) channel selectivity filter GYG motif. The importance of such filter glycines for K(+) selectivity was confirmed by interconversion of Ser-88 and Gly-88 in the rice paralogues OsHKT1 and OsHKT2. Surprisingly, all HKT homologues known from dicots have a serine at the filter position in P-loop A, suggesting that these proteins function mainly as Na(+) transporters in plants and that Na(+)/K(+) symport in HKT proteins is associated with a glycine in the filter residue. These data provide experimental evidence that the glycine residues in selectivity filters of HKT proteins are structurally related to those of K(+) channels. 相似文献
87.
Nuclear cyclin D1 overexpression is a critical event associated with cell proliferation and invasive growth in gallbladder carcinogenesis 总被引:2,自引:0,他引:2
Itoi T Shinohara Y Takeda K Nakamura K Takei K Sanada J Horibe T Saito T Kasuya K Ebihara Y 《Journal of gastroenterology》2000,35(2):142-149
Cyclin D1 overexpression is remarkably frequent in several human carcinomas and is believed to be a critical event in oncogenesis.
We examined cyclin D1 expression, p53 expression, and the Ki-67 labeling index by immunostaining in human gallbladder mucosa in conditions varying from normal
to malignant tissue. We also examined K-ras codon 12 mutations in these tissues with a two-step polymerase chain reaction. Nuclear cyclin D1 overexpression was observed
in 48% of carcinomas occurring independently of adenoma, but not in adenomas, carcinomas arising in adenomas, or nonneoplastic
lesions. Cytoplasmic cyclin D1 overexpression was observed in about 15% of abnormal specimens, irrespective of the type of
epithelial abnormality. Carcinomas showing nuclear cyclin D1 overexpression had significantly higher Ki-67 labeling indexes
than those with no overexpression. Moderately to poorly differentiated adenocarcinomas showed a higher incidence of nuclear
cyclin D1 overexpression than papillary to well differentiated carcinomas. Specimens with cyclin D1 overexpression showed
a high incidence of lymph permeation, venous permeation, and lymph node metastasis. We conclude that nuclear cyclin D1 overexpression
is a critical event importantly associated with cell proliferation and invasive growth in gallbladder carcinogenesis, and
that cyclin D1 immunostaining may become a useful marker for evaluating gallbladder carcinomas.
Received: March 9, 1999 / Accepted: July 23, 1999 相似文献
88.
Sekiguchi T Mizutani T Yamada K Yazawa T Kawata H Yoshino M Kajitani T Kameda T Minegishi T Miyamoto K 《Endocrinology》2002,143(12):4718-4729
89.
Shirato K Morimoto M Tomita N Kokawa A Sugimori K Saito T Tanaka K 《Hepato-gastroenterology》2002,49(46):897-899
A 2.5-cm diameter, exophytic seeding of hepatocellular carcinoma was detected by contrast-enhanced computed tomography in a 76-year-old man. He had previously undergone a radiofrequency ablation therapy with an expandable, ten-hook needle electrode for the treatment of a 1.5-cm hepatocellular carcinoma in liver segment VI. Ultrasound-guided fine needle biopsy revealed that this hepatocellular carcinoma was moderately differentiated, as initial tumor was. An additional radiofrequency ablation achieved complete ablation of this neoplastic mass on contrast-enhanced computed tomography scanning. Recurrences were not found for eight months after. To prevent tumor seeding, using thermocoagulation when retracting the needle electrode may be useful. 相似文献
90.
Staging laparoscopy leads to rapid induction of chemotherapy for unresectable pancreatobiliary cancers 下载免费PDF全文
Daisuke Hashimoto Akira Chikamoto Kazuya Sakata Shigeki Nakagawa Hiromitsu Hayashi Masaki Ohmuraya Masahiko Hirota Naoya Yoshida Toru Beppu Hideo Baba 《Asian journal of endoscopic surgery》2015,8(1):59-62
Preoperatively evaluating the resectability of pancreatobiliary cancers is difficult. The aim of this study was to investigate the benefit of staging laparoscopy in unresectable pancreatobiliary cancers. Between 2010 and 2013, 25 patients with pancreatobiliary cancers underwent staging laparoscopy after conventional tumor staging; they were compared with 10 patients who had unresectable or metastatic tumors that were found during laparotomy. Staging laparoscopy did not show unresectable factors in 11 patients, and resections were performed in these patients. Unresectable factors were found in other 14 patients who underwent staging laparoscopy. In these patients, chemotherapy was started after median postoperative day 3 (range, 2–10 days). This period was significantly longer in patients who received unnecessary laparotomy; chemotherapy was started after median postoperative day 11 (range, 6–15 days). These results suggest that staging laparoscopy, while avoiding laparotomy with unsuccessful resection, can lead to rapid induction of chemotherapy for unresectable pancreatobiliary cancers. 相似文献