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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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Four hundred out of 422 patients with primary gastric cancer seen from 1965 to 1979 underwent surgical treatment and were studied retrospectively. Fifty-eight percent underwent curative procedures. The five year survival rate was 19.14%. Subtotal and total gastrectomy gave survival rates of 35.8% and 9% respectively (p less than 0.05). Postoperative mortality (24.2%) was influenced by both the type of procedure performed (p less than 0.001) and the stage of the neoplasis (p less than 0.001). This study confirms the influence of staging on short, intermediate and long term survival and demonstrates the importance of the early diagnosis of gastric cancer in carrying out effective surgical treatment.  相似文献   
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A new series of N-(substituted)benzyl-1,8-naphthalimides 4, structurally related to the previously reported thymidylate synthase (TS) inhibitor naphthaleins 3, were synthesized and compounds tested for their inhibition of several species of TS. Moreover, their in vitro cytotoxicity together with antimycotic and antibacterial properties were assayed. While no activity was detected in the antibacterial tests, the m-nitro (4ae) and the p-nitro (4af) derivatives were found able to partially inhibit TS at low micromolar concentrations. Introduction of nitro or (substituted)-amino groups in position 4 of the naphthalic ring always led to less active compounds.  相似文献   
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A hypothalamic pathogenesis for the reduced GH secretion in aging has been reported for both animal and man. To further address this issue we studied in 31 elderly normal subjects (6 males and 25 females, aged 66-90 yr) and in 22 young healthy controls (13 males and 9 females, aged 20-35 yr) the GH responses to GHRH test (GHRH29, 1 microgram/kg i.v. as a bolus at 0 min) alone and combined with pyridostigmine, a cholinesterase inhibitor (PD, 120 mg po 60 min before GHRH), or with arginine (ARG, 30 g in 100 ml infused from 0 to 30 min). Serum IGF-I levels were lower in elderly than in young subjects (mean +/- SE: 86.9 +/- 7.2 vs 288.7 +/- 22.1 micrograms/L, p < 0.01). The GHRH-induced GH increase was lower in elderly than in young subjects (p < 0.01). PD increased the GH response to GHRH in both groups (p < 0.001), but in elderly subjects this response persisted lower (p < 0.0001) than that observed in young adults. Also ARG coadministration potentiated the GHRH-induced GH release in both groups (p < 0.0001) but in this case the elderly's responses overlapped with the young's. The GH increase observed after combined administration of ARG and GHRH was higher (p < 0.0001) than that elicited by PD plus GHRH in elderly but not in young subjects. Analyzing individual GH responses, a GH peak below the limit of normality for young adults was observed in 19 (61.3%) elderly subjects after PD plus GHRH administration while ARG plus GHRH test elicited a normal GH peak in all but one.(ABSTRACT TRUNCATED AT 250 WORDS)  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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The purpose of this study was to better understand the molecular composition of the cochlea. Fibronectin (FN), a well characterized adhesive glycoprotein, was localized by immunofluorescence microscopy in fresh and fixed cochlear tissues, and in fixed kidney tissue, using a polyclonal, affinity-purified, rabbit, anti-fibronectin antibody and a secondary antibody coupled to FITC. The FN antibody was free from cross-reactivity with other known basement membrane and cell matrix molecules. FN reactivity in the cochlea was most intense in the basilar membrane, latero-basal borders of Boettcher's cells, otic capsule, endothelial basement membranes (particularly those of the stria vascularis), and as a diffuse, fan-shaped network radiating into the spiral ligament. Little FN labelling was present in the epithelial basement membranes. Negative control tissue showed no immunoreactivity; whereas, positive kidney control tissue showed appropriate FN immunoreactivity in the mesangium of the glomerulus. The most significant finding of this study was that FN is a major component of the basilar membrane and its distribution appears to correspond to the amorphous ground substance. FN was not localized in the organ of Corti or at the tips of the hair-cell stereocilia.  相似文献   
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In the course of a phase I trial, in which recombinant IL-2 (rIL-2) was infused intraperitoneally (i.p.) in patients with peritoneal carcinomatosis, we evaluated the effect on "tumor-associated lymphocytes" (TAL) isolated from the ascitic fluid. No major changes in the percentages of cells expressing the CD3, CD4, CD8, Leu-7, OKM1 and WT-31 antigens were detected either in TAL or in peripheral blood lymphocytes (PBL) after 7 days of rIL-2 infusion. In contrast the percentages of TAL (but not PBL) expressing surface IL-2 receptor (Tac), or LAK-1 antigen were sharply increased. Analysis of cytolytic functions showed a potentiation of the lytic activity against natural-killer (NK) sensitive K562 target cells and the de novo appearance of lytic activity against fresh melanoma cells. In one patient IFN-gamma was detected in the ascitic fluid following rIL-2 infusion. T-cell clones derived from the patient were analyzed for the IFN-gamma production. While only approximately 40% of PB-derived control clones produced medium to low amounts of IFN-gamma, all of the TAL-derived clones produced medium to high amounts of the lymphokine.  相似文献   
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