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The chemical synthesis of the hydroxylated phase-I-metabolites 9 , 11 , and 12 is effected by Triton B catalysed saponification of the bromides 7 and 8 and boron tribromide mediated ether cleavage of 6 and 10 to 11 and 12 . The chelated enol 9 was coupled with the bromosugar 13 to afford the glucuronide 14 that was saponified to the phase-II-metabolite 15 . 相似文献
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Hausegger KA; Cragg AH; Lammer J; Lafer M; Fluckiger F; Klein GE; Sternthal MH; Pilger E 《Radiology》1994,190(1):199
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M Helle H Helin P Ashorn E L Putkinen K Krohn T Wahlstr?m 《Pathology, research and practice》1992,188(1-2):74-77
The tumour antigen expression of ovarian and endometrial endometrioid carcinomas, ovarian clear-cell carcinomas as well as endometrial and cervical clear-cell carcinomas were immunohistochemically compared. Of special interest were potential differences between the endometrioid and clear-cell carcinomas of the ovary. The expression of CEA and CA 19-9 tumour antigens in all these tumour types was heterogeneous, with 10-20% of the cases being positive for CEA and 40-75% being positive for CA 19-9. In contrast, HMFG IIIC 12, a monoclonal antibody originally directed against human milk fat globule (HMFG) membrane antigens, invariably detected a corresponding antigen on every case of these tumour types. Another HMFG antibody, SM IF 3, on the other hand, detected antigenic material on all clear-cell tumour types, but only rarely on endometrioid tumours of the ovary or endometrium. While HMFG IIIC 12 detects an antigen present on all ovarian, endometrial and mammary carcinomas, antibody SM IF 3 thus appears to be more restricted in its staining patterns. Our results with both of these antibodies indicate that ovarian clear-cell carcinomas and ovarian endometrioid carcinomas have antigenic differences, which provides further evidence that they belong to different tumour entities. 相似文献
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Protection Against Chemically-Induced Oxidative Gastrointestinal Tissue Injury in Rats by Bismuth Salts 总被引:1,自引:0,他引:1
Debasis Bagchi Owen R. Carryl Minh X. Tran Manashi Bagchi Phillip J. Vuchetich Roger L. Krohn Siddhartha D. Ray Sekhar Mitra Sidney J. Stohs 《Digestive diseases and sciences》1997,42(9):1890-1900
Oxygen free radicals (OFR) are implicated in thepathogenesis of stress, chemically induced gastriclesions, and gastrointestinal injury. Theconcentration-dependent scavenging abilities of bismuthsubsalicylate (SBS), colloidal bismuth subcitrate (CBS), andselected OFR scavengers, including superoxide dismutase(SOD), catalase, mannitol, and allopurinol were examinedagainst biochemically or chemically generated superoxide anion, hydroxyl radical, andhypochlorite radical plus hypochlorous acid based on achemiluminescence assay. Furthermore, both gastric (GM)and intestinal mucosa (IM) were individually exposed in vitro to these free radical generatingsystems, and the concentration-dependent protectiveabilities of SBS and CBS against lipid peroxidation (LP)were compared with selected OFR scavengers. In addition, 24-hr fasted rats were orally treated with thenecrotizing agents 0.6 M HCl, 0.2 M NaOH, 80% ethanol,and aspirin (200 mg/kg). The extent of tissue injury inthe GM and IM was determined by assessing LP, DNA fragmentation, and membrane microviscosity.Dose- and time-dependent in vivo protective abilities ofCBS (100 mg/kg) and SBS (15 mg/kg) were also assessed.Following incubations with superoxide anion and hydroxyl radical generating systems in thepresence of 125 mg SBS/liter, approximately 47% and 61%inhibitions were observed in the chemiluminescenceresponse, respectively, while 48% and 46% inhibitions were observed with 125 mg CBS/liter. SBS andCBS exerted similar abilities towards hypochloriteradical plus hypochlorous acid. Approx. 3.1- and3.7-fold increases in LP were observed in the GM and IMof rats following oral administration of 0.6 MHCl. Pretreatment of the rats with SBS and CBS decreased0.6 M HCl-induced LP in the GM by approx. 39% and 27%,respectively, with similar decreases in LP in the IM. SBS exhibited better protectiveabilities towards 0.6 M HCl and 0.2 m NaOH-induced GMand IM injury as compared to CBS. SBS and CBS providedsimilar protection towards 80% ethanol-induced gastric injury, while CBS exerted a superior protectiveability towards aspirin-induced gastric injury. Theresults demonstrate that both SBS and CBS can scavengereactive oxygen species and prevent tissue damage produced by OFR. 相似文献
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P L Tisdale B D Collier H M Kauffman M B Adams A T Isitman R S Hellman R G Hoffmann S A Rao T Joestgen L Krohn 《Journal of nuclear medicine》1986,27(8):1266-1272
A prospective evaluation of 111In-labeled platelet scintigraphy (IPS) for the early diagnosis of acute postoperative renal transplant rejection (TR) was undertaken. The results of IPS were compared with in vitro biochemical tests, the clinical finding of graft tenderness, and combined [99mTc]DTPA and [131I]orthoiodohippurate scintigraphy. With a sensitivity of 0.93 and a specificity of 0.95, IPS provided otherwise unavailable diagnostic information. Furthermore, postoperative IPS was a good predictor of long-term allograft survival. 相似文献