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排序方式: 共有2094条查询结果,搜索用时 15 毫秒
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Akinori Mitsui Midori Yoshizawa Hiromichi Matsumoto Emiko Fukui 《Journal of assisted reproduction and genetics》2009,26(1):35-39
Purpose The effects of reciprocal transplantation of meiosis-II chromosomes between senescent and young mouse oocytes were evaluated
based on pre- and post-implantation development ability of resultant embryos.
Methods Karyoplasts including meiosis-II chromosomes of oocytes from senescent Rockefeller mouse/Ms-Rb(6, 15) females (10 to 12 months,
age-related infertile mice) were transferred into cytoplasts of oocytes from young F1 females (3 to 5 months). Reconstructed oocytes were fertilized in vitro, and then the resultant embryos were cultured in
vitro and transferred to recipient mice.
Results The reconstructed oocytes that consisted of aged-karyoplasts and young-cytoplasts showed significantly improved embryonic
development (from 23.2% to 30.0%) and development to term (from 6.3% to 27.1%, P < 0.05) as compared with the oocytes reconstructed from young-karyoplasts and aged-cytoplasts.
Conclusions The present study showed successful rejuvenation for age-related infertility using transplantation of meiosis-II chromosomes
in animal experimental models.
Capsule Transplantation of meiosis-II chromosomes of senescent mouse oocytes into cytoplasts of young mouse oocytes improves subsequent
embryonic and fetal development until birth. 相似文献
34.
Extremely early onset of ranitidine action on human histamine H2 receptors expressed in HEK293 cells
Fukushima Y Ishikawa T Saitoh T Tateishi K Ogihara T Fujishiro M Shojima N Honda M Kushiyama A Anai M Sakoda H Ono H Onishi Y Otsuka H Katagiri H Nagai R Omata M Asano T 《Digestion》2003,68(2-3):145-152
BACKGROUND/AIMS: Histamine H2 receptor antagonists are considered to exert their effects on gastric acid secretion more rapidly than proton pump antagonists. However, there are no reports concerning the direct interaction of a histamine H2 receptor antagonist with the human H2 receptor in terms of onset of action. This study aims to characterize how rapidly famotidine and ranitidine, the most widely used histamine H2 receptor antagonists, interact with the human histamine H2 receptor. METHODS: HEK293 cell lines, stably expressing human histamine H2 receptors, were obtained. The dose- and time-dependent effects of famotidine and ranitidine on [3H]-tiotidine binding and histamine-stimulated cAMP production were analyzed. RESULTS: Ranitidine inhibited both [3H]-tiotidine binding and histamine-stimulated cAMP production more promptly than did famotidine. Inhibition of histamine-stimulated cAMP production by Cmax doses of famotidine (20 mg p.o.) and ranitidine (150 mg p.o.) peaked by 15 and 2 min, respectively. [3H]-tiotidine binding was not saturated by 60 min at the famotidine Cmax, while the ranitidine Cmax had produced saturation by 15 min. CONCLUSION: Ranitidine inhibits the human histamine H2 receptor very rapidly. 相似文献
35.
Yoneda M Sanada H Yatabe J Midorikawa S Hashimoto S Sasaki M Katoh T Watanabe T Andrews PM Jose PA Felder RA 《Hypertension》2005,46(1):58-65
The effect of selectively decreasing renal angiotensin II type 1 (AT1) receptor expression on renal function and blood pressure has not been determined. Therefore, we studied the consequences of selective renal inhibition of AT1 receptor expression in normotensive Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) in vivo. Vehicle, AT1 receptor antisense oligodeoxynucleotides (AS-ODN), or scrambled oligodeoxynucleotides were infused chronically into the cortex of the remaining kidney of conscious, uninephrectomized WKY and SHR on a 4% NaCl intake. Basal renal cortical membrane AT1 receptor protein was greater in SHR than in WKY. In WKY and SHR, AS-ODN decreased renal but not cardiac AT1 receptors. AT1 receptor AS-ODN treatment increased plasma renin activity to a greater extent in WKY than in SHR. However, plasma angiotensin II and aldosterone were increased by AS-ODN to a similar degree in both rat strains. In SHR, sodium excretion was increased and sodium balance was decreased by AS-ODN but had only a transient ameliorating effect on blood pressure. Urinary protein and glomerular sclerosis were markedly reduced by AS-ODN-treated SHR. In WKY, AS-ODN had no effect on sodium excretion, blood pressure, or renal histology but also modestly decreased proteinuria. The major consequence of decreasing renal AT1 receptor protein in the SHR is a decrease in proteinuria, probably as a result of the amelioration in glomerular pathology but independent of systemic blood pressure and circulating angiotensin II levels. 相似文献
36.
Kihara Mari Sugihara Takahiko Asano Junichi Sato Midori Kaneko Hiroshi Muraoka Sei Ohshima Shiro Nanki Toshihiro 《Clinical rheumatology》2022,41(12):3661-3673
Clinical Rheumatology - To describe clinical characteristics of patients in Japan with coronavirus disease 19 (COVID-19) and pre-existing rheumatic disease and examine the possible risk factors... 相似文献
37.
O. Goto M. Fujishiro N. Kakushima S. Kodashima S. Ono H. Yamaguchi S. Nomura M. Kaminishi M. Omata 《Digestive and liver disease》2008,40(4):293-297
BACKGROUND: Endoscopic submucosal dissection is a novel endoluminal technique that enables resection of early stage gastrointestinal malignancies in an en bloc fashion. AIM: To assess whether preceding endoscopic submucosal dissection affected the prognoses of patients who underwent additional gastrectomy with lymph node dissection due to suspicion of nodal metastasis from endoscopic submucosal dissection specimens. PATIENTS AND METHODS: Thirty-one patients with early gastric cancer who underwent gastrectomy after endoscopic submucosal dissection were retrospectively investigated in terms of their survival and tumour recurrence. Additional gastrectomy was performed when histology of the endoscopic submucosal dissection specimens revealed that the tumours did not meet the criteria for node-negative cancers. RESULTS: Twenty-three (74%) and eight (26%) patients had undergone endoscopic submucosal dissection previously due to clinical diagnoses of node-negative cancers and possible node-positive cancers, respectively. Histology of the resected stomachs and lymph nodes revealed residual carcinoma of the stomach in two (6.5%) patients and nodal metastases in four (13%) patients. All patients remain alive without recurrence (median follow-up, 3.4 years; range, 0.6-5.2 years). CONCLUSIONS: Based on the histology of endoscopic submucosal dissection specimens, preceding endoscopic submucosal dissection itself had no negative influence on a patient's prognosis when additional gastrectomy was performed. It may be permissible to resect some early gastric cancers by endoscopic submucosal dissection as a first step to prevent unnecessary gastrectomy, if technically resectable. 相似文献
38.
39.
Haruno Nishimuro Hirofumi Ohnishi Midori Sato Mayumi Ohnishi-Kameyama Izumi Matsunaga Shigehiro Naito Katsunari Ippoushi Hideaki Oike Tadahiro Nagata Hiroshi Akasaka Shigeyuki Saitoh Kazuaki Shimamoto Masuko Kobori 《Nutrients》2015,7(4):2345-2358
Quercetin is a promising food component, which can prevent lifestyle related diseases. To understand the dietary intake of quercetin in the subjects of a population-based cohort study and in the Japanese population, we first determined the quercetin content in foods available in the market during June and July in or near a town in Hokkaido, Japan. Red leaf lettuce, asparagus, and onions contained high amounts of quercetin derivatives. We then estimated the daily quercetin intake by 570 residents aged 20–92 years old in the town using a food frequency questionnaire (FFQ). The average and median quercetin intakes were 16.2 and 15.5 mg day−1, respectively. The quercetin intakes by men were lower than those by women; the quercetin intakes showed a low correlation with age in both men and women. The estimated quercetin intake was similar during summer and winter. Quercetin was mainly ingested from onions and green tea, both in summer and in winter. Vegetables, such as asparagus, green pepper, tomatoes, and red leaf lettuce, were good sources of quercetin in summer. Our results will help to elucidate the association between quercetin intake and risks of lifestyle-related diseases by further prospective cohort study and establish healthy dietary requirements with the consumption of more physiologically useful components from foods. 相似文献
40.
Hisada Hiroyuki Tsuji Yosuke Obata Miho Cho Rina Nagao Sayaka Miura Yuko Mizutani Hiroya Ohki Daisuke Yakabi Seiichi Takahashi Yu Sakaguchi Yoshiki Kakushima Naomi Yamamichi Nobutake Fujishiro Mitsuhiro 《Journal of gastroenterology》2022,57(12):952-961
Journal of Gastroenterology - Sarcopenia prevalence has increased in proportion to the aging population in Japan. We aimed to investigate the association between sarcopenia and clinical outcomes... 相似文献