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排序方式: 共有6722条查询结果,搜索用时 78 毫秒
21.
Chihaya Maesawa Gen Tamura Yasushi Suzuki Kaoru Ishida Kazuyoshi Saito Ryoichi Satodate 《Cancer science》1992,83(12):1253-1256
For the rapid and sensitive detection of p53 gene mutations in esophageal endoscopic biopsy specimens, we combined cell sorting with the polymerase chain reaction and single-strand conformation polymorphism (PCR-SSCP) analysis. Mutations in exons 5–8 of the p53 gene were investigated by FCR-SSCF analysis using 103 sorted nuclei obtained from each endoscopic biopsy specimen of 16 patients with esophageal cancer. DNAs extracted from their respective surgical specimens were investigated by a conventional method of PCR-SSCP analysis. Mutations in the biopsy specimens were detected in 6 of the 12 aneuploid tumors but in none of the 4 diploid tumors. After tumor cell enrichment by cell sorting, one mutation in exon 8 became apparent, which could not be detected from the surgical specimen by a conventional method of PCR-SSCP analysis. This method should improve the sensitivity of detecting p53 gene mutations, and provides additional information concerning the DNA ploidy pattern in the tumors. 相似文献
22.
23.
F Omata Y Ichikawa Y Kushibiki H Shimizu M Yoshida M Komatsuda S Arimori 《American journal of hematology》1992,40(2):160-161
24.
T Ohashi F Yamamoto H Yamamoto H Ichikawa T Shibata Y Shimada T Ishikawa K Kagisaki Y Kumada Y Kawashima 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1992,40(11):1998-2004
The effects of potassium in reperfusion solution (RS) and the influence of sodium on this effect were studied. Experimental time course was as followed: 20 min working perfusion, 3 min cardioplegic infusion with St. Thomas Cardioplegic Solution followed by global ischemia for 33 or 35 min at 37.5 degrees C, 15 min early Langendorff reperfusion with several different potassium concentration modified with Krebs Henseleit Bicarbonate Buffer (KHBB) containing 145 mM and 110 mM sodium and 5 min late reperfusion with KHBB, followed by 20 min working perfusion. Potassium in RS possessed bell shaped dose response nature with optimal concentration of 10 mM in the condition of 145 mM sodium but 6 m in the condition of 110 mM in terms of percent recovery of aortic flow. Although higher potassium reperfusion produced less Creatine Kinase leakage. 相似文献
25.
26.
Inhibitory action of tranilast, an anti-allergic drug, on the release of cytokines and PGE2 from human monocytes-macrophages. 总被引:1,自引:0,他引:1
Tranilast, an anti-allergic drug that inhibits the release of substances such as histamine and prostaglandins from mast cells, has been reported to improve keloids and hypertrophic scars which originate from the abnormal proliferation and excessive collagen accumulation of fibroblasts. It has been considered that various chemical mediators produced by inflammatory cells play important roles in the development of keloids and hypertrophic scars. We therefore studied the effect of tranilast on the release of chemical mediators including transforming growth factor (TGF)-beta 1, interleukin (IL)-1 beta and prostaglandin (PG) E2 which are produced by the human monocytes-macrophages, and estimated whether these mediators induce collagen synthesis and cell proliferation of normal skin fibroblasts. Tranilast inhibited the release of TGF-beta 1, IL-1 beta and PGE2 from the human monocytes-macrophages. TGF-beta 1 (25-200 pM) enhanced the collagen synthesis by fibroblasts. IL-1 (0.1-1 U/ml) increased the proliferation and conversely decreased the collagen synthesis. PGE2 (2 micrograms/ml) enhanced the collagen synthesis. These results suggest that tranilast suppresses collagen synthesis by fibroblasts through inhibiting TGF-beta 1 and PGE2 production and cell proliferation by fibroblasts through inhibiting IL-1 production by inflammatory cells such as macrophages. 相似文献
27.
Junichi Taki Akihiro Ichikawa Kenichi Nakajima Michio Kawasuji Norihisa Tonami 《European journal of nuclear medicine and molecular imaging》1997,24(12):1487-1493
Stress thallium-201 tomography was performed to compare the flow capacities of arterial and saphenous vein grafts in patients
with coronary artery bypass grafting (CABG). One hundred and seven consecutive patients (95 male and 12 female; mean age 58±9.1
years) underwent exercise-redistribution 201Tl myocardial single-photon emission tomography 4–5 weeks after CABG. When a reversible perfusion defect was present in the
area covered by a patent bypass graft, the flow capacity of the graft was defined as insufficient. Of all 285 grafts, 211
were considered as complete bypass. Reversible perfusion defects were present in 29 (27%) of 108 myocardial areas supplied
by patent arterial grafts but in only 5 (5%) of 103 myocardial areas supplied by patent saphenous vein grafts (P<0.0001). In the LAD area reversible defects were observed in 22 of 82 areas covered by arterial grafts, in contrast to only
1 of 29 areas covered by venous grafts (P<0.01); in the RCA area reversible defects were observed in 7 of 17 and 4 of 41 areas respectively (P<0.01). There was no difference between the native coronary artery stenosis bypassed by patent arterial and venous grafts
(88%±12% vs 86%±14% respectively, P=0.27). In conclusion, flow capacities during peak myocardial demand were more frequently insufficient in arterial bypass
grafts than in saphenous vein grafts.
Received 23 May and in revised form 7 August 1997 相似文献
28.
Masayuki Mano Akira Sugawara Yasuo Nara Kazuwa Nakao Ryoichi Horie Jiro Endo Hiroo Imura Yukio Yamori 《Clinical and experimental pharmacology & physiology》1992,19(12):795-801
1. Effects of potassium (K) supplementation (100 mEq/day) on urinary sodium (Na) excretion and on the secretion of atrial natriuretic polypeptide (ANP) during salt loading (350 mEq/day) were studied in 12 healthy salt-resistant normotensives under strictly controlled metabolic ward conditions. 2. Urinary volume and Na excretion on the first day of the high salt period (HSP) were significantly greater in the K-supplemented group (KG) than in the control group (CG). 3. There was a significant gain in bodyweight after salt loading in both groups, with a significantly greater gain in CG on the second day of HSP. Haematocrit decreased significantly during salt loading in both groups, the degree of which was significantly greater in CG. 4. Plasma norepinephrine decreased significantly during salt loading in both groups, the degree of which was significantly less in KG than in CG. A significant increase in plasma ANP was observed in CG on and after the second day of HSP, while a significant increase in plasma ANP was observed on the fifth day of HSP in KG. 5. These findings indicate that K supplementation accelerates diuresis and natriuresis, resulting in moderate suppression of volume expansion induced by salt loading and that this accelerated diuresis and natriuresis is not a result of the action of ANP. 相似文献
29.
S Nagano N Fujimoto M Kyo Y Ichikawa M Ishibashi S Takahara H Ihara M Nojima Y Kato A Hirano 《Hinyokika kiyo. Acta urologica Japonica》1992,38(9):1083-1088
A statistic analysis was carried out on the 4,956 inpatients admitted to our Department of Urology from April 1972 to December 1991. The patients included 3,399 males and 1,557 females. A total of 4,105 operations including 255 renal allotransplantations were performed on 3,590 patients. Open surgery for upper urinary tract stones has been replaced by extracorporeal shock-wave lithotripsy (ESWL) in the last three years. 相似文献
30.