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1.
用混合粘合剂碳糊电极测定丁螺环酮   总被引:6,自引:1,他引:5  
用混合粘合剂碳糊电极测定丁螺环酮张正奇,曾鸽鸣,刘传桂,黎艳飞(湖南大学化学化工系,长沙410082)碳糊电极无毒,制作方便,表面更新容易,应用电位范围广,在药物分析中已有应用[1~5]。我们在液体石腊中加入添加剂,组成混合粘合剂,可显著改善电极的检...  相似文献   
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From Jan 1, 1978 through Dec 31, 1983, 64 patients with epithelial ovarian tumors, frankly malignant or borderline, were managed at one institution. Nineteen patients (29.7%) were under age 40. The youngest patient was 19 years old. Nulliparity was present in 32% of this group of patients. Of these young patients, 58% had borderline epithelial tumors, compared to 13% of patients over 40 years of age. Twenty-one percent of the young patients were initially managed by unilateral adnexal surgery. The overall cumulative actuarial survival rate of all young patients was 93%. Young patients with epithelial ovarian tumors tend to have earlier grades of epithelial neoplasms, and survival is better than that reported for older patients with similar tumors.  相似文献   
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CG Teo 《Oral diseases》2002,8(S2):88-90
Oral hairy leukoplakia (OHL) and Kaposi's sarcoma (KS) are commonly encountered in the HIV-infected patient. A unique feature of OHL is non-cytolytic high level of replication of Epstein–Barr virus (EBV) in the glossal epithelium. The expression of viral-encoded anti-apoptotic proteins concomitant to replicative proteins probably underlies this phenomenon. The question of whether OHL arises from activation of EBV latent in the tongue, or from superinfection by endogenous EBV shed via non-glossal sites or by exogenous EBV remains unresolved. Human herpesvirus 8 (HHV8) is now seen as necessary but not sufficient cause of KS. Expression of HHV8-encoded oncogenic proteins in endothelial cells probably explains the aberrant proliferation of these cells in KS lesions. Studies into why KS is so commonly observed at the palate in HIV-infected patients may provide important clues to its pathogenesis.  相似文献   
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Over a 10-year period, 65 of 196 patients (33%) with ovarian epithelial malignancy, previously treated with chemotherapy, had a second-look operation if the disease was clinically absent. All procedures were done by one of three gynecologic oncologists, and 48% of the patients had a positive second-look procedure. Of patients with original stage I, II disease, 25% had a positive second-look operation, contrasting with 61% of patients with stage III, IV. Significant perioperative morbidity occurred: one patient had intraoperative vascular collapse; 15% had prolonged ileus; 17% had small bowel resections at the time of the second-look operation or in the postoperative period. Of all patients with negative second-look operations, 24% have had recurrent disease from 5 to 23 months after the procedure. These recurrences were in the liver or distant sites in 63% of the patients. Second-look operations, if still indicated by negative noninvasive techniques, should be performed in tertiary care centers under study situations in a standard fashion.  相似文献   
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This report describes the use of counterimmunoelectrophoresis (CIE) as a method of detecting activation of the complement system. With this technic small amounts of C3 split products (C3c/d) can be detected in plasma samples by specific precipitation with antiserum in less than two hours. The CIE technic is a highly sensitive, rapid method for detecting activation of the complement system in the presence of normal concentrations of C3 measured hemolytically or by radial immunodiffusion (RID) in human disease. A clinical investigation was carried out in 40 patients with systemic rheumatic diseases and 116 normal healthy individuals. The following observations were made: (1) plasmas and sera from normal individuals had normal total complement hemolytic activity (CH50), hemolytic active C4 (C4H50) and C3 (C3H50); (2) in 30% of the serum samples it was possible to identify the presence of C3 split products, in contrast to only 2.5% of the plasma samples obtained simultaneously; (3) in the specimens from patients who had rheumatic disease activity, C3 split products were identified by CIE in all cases except one in the presence of normal C3 protein measured by RID.  相似文献   
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The present study investigated the effects of dietary oltipraz on cigarette smoke-related lipophilic DNA adduct formation. Female Sprague- Dawley rats were exposed daily to sidestream cigarette smoke in a whole- body exposure chamber 6 h/day for 4 consecutive weeks. One group of rats was maintained on control diet while another group received the same diet supplemented with either a low (167 p.p.m.) or high (500 p.p.m.) dose of oltipraz, starting 1 week prior to initiation of smoke exposure until the end of the experiment. Analysis of lipophilic DNA adducts by the nuclease P1-mediated 32P-post-labeling showed up to five smoke-related adducts. Adduct no. 5 predominated in both the lung and the heart while adduct nos 3 and 2 predominated in the trachea and bladder, respectively. Quantitative analysis revealed that the total adduct level was the highest in lungs (270+/-68 adducts/10(10) nucleotides), followed by trachea (196+/-48 adducts/10(10) nucleotides), heart (141+/-22 adducts/10(10) nucleotides) and bladder (85+/-16 adducts/10(10) nucleotides). High dose oltipraz treatment reduced the adduct levels in lungs and bladder by >60%, while the reduction in lungs in the low-dose group was approximately 35%. In trachea, the effect of low and high dietary oltipraz on smoke DNA adduction was equivocal, while smoke-related DNA adducts in the heart were minimally inhibited by high-dose oltipraz. In a repeat experiment that employed a 3-fold lower dose of cigarette smoke, oltipraz (500 p.p.m.) was found to inhibit the formation of DNA adducts in rat lungs and trachea by 80 and 65%, respectively. These data clearly demonstrate a high efficacy of oltipraz in inhibiting the formation of cigarette smoke-induced DNA adducts in the target tissues.   相似文献   
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