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81.
Phospholipid transfer protein (PLTP) was purified from lipoprotein-free human plasma, obtained upon treatment of plasma with dextran sulfate and Ca2+, by employing a series of column chromatography. Upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the purified PLTP showed a single main band, corresponding to the molecular mass of 78 kDa. However, isoelectric focusing of the purified preparation gave multiple bands with pI ranging from 4.3 to 5.1, indicative of microheterogeneity. Purified PLTP was shown to possess not only phospholipid transfer activity, but also high density lipoprotein (HDL) conversion activity (Tu, A.-Y., Nishida, H. I., and Nishida, T. (1990), FASEB J. 4, A2148; Jauhiainen, M., Metso, J., Pahlman, R., Blomqvist, S., van Tol, A., and Ehnholm, C. (1993) J. Biol. Chem. 268, 4032-4036). Isolated HDL3 was enlarged to the size of HDL2b upon incubation with purified PLTP for 6 h at 37 degrees C at the PLTP/HDL3 molar ratio of approximately 1:45. Both the HDL conversion and the phosphatidylcholine transfer activities of purified PLTP were effectively inhibited by rabbit anti-PLTP immunoglobulin G. The primary importance of PLTP in the HDL enlargement that occurs in human plasma upon incubation at 37 degrees C was shown by the strong inhibitory effect of the anti-PLTP immunoglobulin G. The process of PLTP-mediated HDL enlargement was accompanied by the release of apoproteins, primarily apoA-I. HDL3 enlargement mediated by PLTP was effectively inhibited by the addition of free fatty acids.  相似文献   
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Assessed the impact of school-based social competence training on skills, social adjustment, and self-reported substance use of 282 6th and 7th graders. Training emphasized broad-based competence promotion in conjunction with domain-specific application to substance abuse prevention. The 20-session program comprised 6 units: stress management, self-esteem, problem solving, substances and health information, assertiveness, and social networks. Findings indicated positive training effects on Ss' skills in handling interpersonal problems and coping with anxiety. Teacher ratings revealed improvements in Ss' constructive conflict resolution with peers, impulse control, and popularity. Self-report ratings indicated gains in problem-solving efficacy. Results suggest some preventive impact on self-reported substance use intentions and excessive alcohol use. In general, the program was found to be beneficial for both inner-city and suburban students. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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PURPOSE: This multicenter, randomized phase III clinical trial evaluated the efficacy of etoposide plus carboplatin (EC) versus etoposide plus cisplatin (EP) in good-risk germ cell tumor (GCT) patients. PATIENTS AND METHODS: Between October 1986 and December 1990, 270 patients with good-risk GCTs were randomized to receive four cycles of either EP or EC. The etoposide dose in all patients was 100 mg/m2 on days 1 through 5. EP patients received cisplatin at 20 mg/m2 on days 1 through 5 and therapy was recycled at 21-day intervals. For EC patients, the carboplatin dose was 500 mg/m2 on day 1 of each cycle and the EC recycling interval was 28 days. RESULTS: Two hundred sixty-five patients were assessable: 131 patients treated with EC and 134 treated with EP. One hundred fifteen of 131 assessable patients (88%) treated with EC achieved a complete response (CR) versus 121 of 134 patients (90%) treated with EP (P = .32). Sixteen patients (12%) treated with EC relapsed from CR versus four patients (3%) treated with EP. Therefore, 32 patients (24%) who received carboplatin experienced an event (incomplete response [IR] or relapse) compared with 17 of 134 patients (13%) who received cisplatin (P = .02). At a median follow-up of 22.4 months, event-free and relapse-free survival were inferior for patients treated with EC (P = .02 and P = .005, respectively). No difference in overall survival was evident (P = .52). CONCLUSION: Two-drug therapy with EC using this dose and schedule was inferior to therapy with EP. Cisplatin remains as the standard platinum analog in the treatment of patients with good-risk GCTs. Carboplatin should be restricted to investigational trials in GCT.  相似文献   
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Definition of the immune process that causes demyelination in multiple sclerosis is essential to determine the feasibility of Ag-directed immunotherapy. Using the nonhuman primate, Callithrix jacchus jacchus (common marmoset), we show that immunization with myelin basic protein and proteolipid protein determinants results in clinical disease with significant demyelination. Demyelination was associated with spreading to myelin oligodendrocyte glycoprotein (MOG) determinants that generated anti-MOG serum Abs and Ig deposition in central nervous system white matter lesions. These data associate intermolecular "determinant spreading" with clinical autoimmune disease in primates and raise important issues for the pathogenesis and treatment of multiple sclerosis.  相似文献   
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米糠油或稻米油从很多方面来看都是一种健康植物油。与其他植物油相比,米糠油具有均衡的脂肪酸,拥有较高含量且独特的微量成分、微量营养素或不皂化物。目前研究表明,米糠油中的谷维素含量超过1.5%,提供了营养和药物功能。更多的研究在开展中来证明米糠油多方面的广泛功能。米糠油富含植物甾醇,有许多研究关注其营养应用价值。此外,米糠油含有生育酚和生育三烯酚,尤其后者具有许多特殊功能,如预防乳腺癌等。越来越多地营养学或生物学研究证明,当米糠油适当加工后在食品中使用时,具有特殊功能。因此,在学术研究和产业实践中,都在探索米糠油在食品和制药领域的应用。对米糠油的营养应用进展做简要综述。  相似文献   
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