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51.
美国约有30%的糖尿病患者(约620万人)被漏诊。超过25%的新诊断糖尿病患者已经患有糖尿病视网膜病变或出现微量白蛋白尿,这意味着患者在2型糖尿病发病和确诊之间被“忽视”了7年。有时发现在糖尿病前期,即空腹血糖(FPG)略有偏高(IFG,空腹血糖受损)或口服葡萄糖耐量试验(OGTT)略有偏高,甚至已存在微血管和大血管并发症。  相似文献   
52.
Our aim was to establish an effective non-surgical treatment for cervical intraepithelial neoplasia (CIN) through inactivation of human papillomavirus (HPV), the major etiological agent for this disease. We show that vidarabine, a DNA polymerase inhibitor, suppressed growth and HPV gene expression in human cervical keratinocytes immortalized by HPV or in cervical cancer cell lines. Expression of HPV-16 E6 and E7 proteins in normal cervical keratinocytes sensitized cells to apoptosis in the presence of podophyllin or vidarabine. We applied vidarabine ointment and/or podophyllin to cervical epithelium in 28 cases of CIN I-II to evaluate the therapeutic effectiveness of these agents. Co-application of vidarabine and podophyllin in six treatments caused regression of lesions cytologically and histologically, and disappearance of HPV-16 or -18 DNA in 17 of 21 (81%) women. Our results suggest that the combination of vidarabine and podophyllin therapy is an effective non-surgical treatment for HPV-positive CIN.  相似文献   
53.
Bioavailability evaluation of a controlled-release dextromethorphan liquid   总被引:5,自引:0,他引:5  
A randomized, two-way, steady-state crossover study was performed in 24 healthy male volunteers to evaluate the bioavailability of a controlled-release (CR) dextromethorphan (DM) suspension. Only slow and intermediate DM metabolizers were allowed to participate in the study; determination of metabolizer status was performed before study enrollment. Each volunteer was administered 30 mg of an immediate-release (IR) DM solution qid or 60 mg DM as a CR suspension bid for two weeks, for a total daily dose of 120 mg. After a two-week washout period, the subjects were administered the alternate treatment. Blood samples were collected over a 12-hour dosing period on the last day of each treatment and analyzed for DM and its active metabolite, dextrorphan (DP). In addition, urine was collected over the 12-hour steady-state dosing interval and measured for DM and two metabolites. Pharmacokinetic determinations were made from plasma DM and DP data, and total urinary excretion was determined. All comparisons made between the two formulations indicated that the CR DM suspension was bioequivalent to the IR DM solution at steady state, while producing a prolonged release of the drug over time.  相似文献   
54.
A depletion of intracellular glutathione (GSH) is accompanied by a subsequent inhibition of GSH-S-transferase activity in a DU145 human prostatic carcinoma cell line treated with cytotoxic concentrations of estramustine. When GSH depletion reached approximately 50% of normal (approximately 2 hours after 10 microM estramustine), the mitotic index of logarithmically dividing cultures began to increase. A linear increase from 3.14% to 22.5% occurred during the period of 2-24 hours following 10 microM estramustine. Morphological studies showed that mitotic figures accumulated in metaphase and had abnormalities consistent with spindle malformation. Nocodazole and cytochalasin B also possess anticytoskeletal properties, but had little effect upon the intracellular levels of GSH or its associated transferase enzymes. The constituent moieties of estramustine, estradiol, and nor-mechlorethamine had effects on thiol metabolism which were dissimilar from estramustine, confirming previous findings that the unmetabolized parent drug is responsible for pharmacological activity. Estramustine had no effect upon GSH reductase activity, suggesting that drug toxicity was not a general thiol phenomenon. Buthionine sulfoximine decreased intracellular GSH in DU145 cells and enhanced the cytotoxic potential of estramustine in this cell line. The anticytoskeletal and antimitotic properties of estramustine may be enhanced by the drug-induced GSH imbalance and subsequent effects on GSH-S-transferase enzymes.  相似文献   
55.
Human papillomavirus (HPV) DNAs are detected in approximately 90% of anogenital carcinomas. To assess directly the effect of HPV on squamous differentiation, normal human cervical and foreskin epithelial cells and cells immortalized by recombinant HPV DNAs were transplanted beneath a skin-muscle flap in athymic mice. Xenografts containing normal cells formed well-differentiated stratified squamous epithelia 2 to 3 weeks after transplantation, but cell lines immortalized by four HPV types (HPV16, HPV18, HPV31, and HPV33) detected in anogenital cancer exhibited dysplastic morphology and molecular alterations in gene expression characteristic of intraepithelial neoplasia. Morphological alterations were accompanied by delayed commitment to terminal differentiation, alterations in the pattern of involucrin expression, and reductions in levels of involucrin and keratin 1 RNAs. HPV18-immortalized cells developed dysplastic changes more rapidly than cells immortalized by HPV16 DNA. These results show that human genital epithelial cells immortalized by HPV DNAs detected in genital cancers undergo dysplastic differentiation in vivo.  相似文献   
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Adolescents who abuse alcohol are being admitted to treatment centers in increasing numbers. However, relapse prevention, a critical aspect of recovery, rarely is addressed in this high-risk population. This article briefly reviews adolescent development, the current literature on adolescent drinking patterns and relapse, and analyzes current models of relapse prevention in adults. This information is then used to propose a relapse prevention model for adolescents.  相似文献   
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