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991.
BACKGROUND: The study aim was to investigate the relationship between insulin resistance (IR), beta-cell function (betaF), hyperandrogenism and proinsulin levels during an oral glucose tolerance test (OGTT) in women with polycystic ovary syndrome (PCOS). METHODS: One hundred and twenty-six selected women were classified as follows: PCOS, BMI > 25 kg/m2 (n = 39); PCOS, BMI < 25 kg/m2 (n = 54); controls, BMI > 25 kg/m2 (n = 14); controls, BMI < 25 kg/m2 (n = 19). Blood samples were collected between the third and sixth day of a spontaneous menstrual cycle, at 9:00 a.m., after an overnight fast. Serum levels of FSH, LH, PRL, 17alpha-OH-progesterone, SHBG, testosterone, delta4-androstenedione, insulin, proinsulin and glucose were measured. A 75 g OGTT was performed, and concentrations of glucose, insulin and proinsulin were also measured at t = 30, 60, 90, and 120 min. RESULTS: The markers of insulin secretion and the AUC for proinsulin were higher in obese and overweight women and in women with PCOS, respectively. The AUC for proinsulin was positively correlated with markers of IR, betaF and androgen levels. An inverse relationship between PI/I values and indices of IR and betaF was observed. CONCLUSIONS: Increased proinsulin levels reflect, most probably, insulin resistance, which is the key disorder in PCOS-associated metabolic abnormalities. Beta-cell function, pre-proinsulin mRNA processing and proinsulin conversion to insulin could be initially increased as a result of IR. An interaction between circulating proinsulin and androgen biosynthesis or action might also exist.  相似文献   
992.
A novel patient individualized, spatiotemporal Monte Carlo simulation model of tumor response to chemotherapeutic schemes in vivo is presented. Treatment of glioblastoma multiforme by temozolomide is considered as a paradigm. The model is based on the patient's imaging, histopathologic and genetic data. A discretization mesh is superimposed upon the anatomical region of interest and within each geometrical cell of the mesh the most prominent biological "laws" (cell cycling, apoptosis, etc.) in conjunction with pharmacokinetics and pharmacodynamics information are applied. A good qualitative agreement of the model's predictions with clinical experience supports the applicability of the approach to chemotherapy optimization.  相似文献   
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Purpose

To assess the antitumor activity and toxicity of gemcitabine, cisplatin, and docetaxel (GCD) regimen in patients with locally advanced or metastatic urothelial cancer.

Patient and methods

Chemotherapy-na?ve patients, aged ??70?years with measurable or evaluable disease and a performance status (PS) of 0?C2 were treated with sequential cisplatin 80?mg/m2 (d1), gemcitabine 1,100?mg/m2 (d1 and d14), and docetaxel 80?mg/m2 (d14) every 28?days.

Results

Sixty patients with an ECOG PS of 0?C2 were enroled. Most (71.7%) patients had stage IV disease. A median number of 4 chemotherapy cycles per patient (range, 1?C9) was administered. Eight (13.3%) patients achieved a CR and 16 (26.7%) a partial response (PR) (intention-to-treat: ORR 40%; 95% CI 27.6?C52.4%). Thirteen (21.7%) and 23 (38.3%) patients experienced stable and progressive disease, respectively. The median time to progression (TTP) was 7.7?months (range, 0.7?C43.4), and the median overall survival 21.4?months (range, 0.7?C68.6). Grade 3 and 4 neutropenia occurred in 27 (45%) patients and grade 3 and 4 thrombocytopenia in five (8.3%). Three (5%) patients developed febrile neutropenia. There were no treatment-related deaths. Severe non-haematological toxicity was infrequent.

Conclusions

The GCD combination is an active and well-tolerated regimen in patients with chemotherapy-naive locally advanced or metastatic TCC and merits to be further investigated.  相似文献   
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BackgroundThe purpose of this study was to evaluate the efficacy of erlotinib as front-line treatment in clinically selected patients with non–small-cell lung cancer (NSCLC).Patients and MethodsForty-nine previously untreated white patients who had stage IIIB/IV pulmonary adenocarcinoma or bronchoalveolar carcinoma and who were nonsmokers or former light smokers were treated with erlotinib 150 mg daily, irrespective of the EGFR mutation status.ResultsIn an intention-to-treat analysis, the overall response rate (ORR) was 24.5%. The median progression-free survival (PFS) was 6.7 months, the median overall survival (OS) was 15.5 months, and the 1-year survival rate was 61.3%. Among the 36 patients for whom tumor material was available, 9 (25%) had activating EGFR mutations. The ORR was 66.7% in patients with activating EGFR mutations and 14.8% in patients with wild-type EGFR (2P = .006). In patients with activating EGFR mutations, the OS has not been reached, whereas it was 12.9 months in patients with EGFR wild type (2P = .045). Twenty-four patients had a PFS of > 6 months; 11 (45.8%) of them had EGFR wild type and 7 (29.1%) had EGFR mutation.ConclusionsThe selection of patients for treatment with EGFR-directed tyrosine kinase inhibitors (TKIs) should be based on mutation testing. However use of clinical (smoking status) and pathologic (adenocarcinoma) criteria may identify a subgroup of patients with advanced/metastatic NSCLC who can benefit from front-line treatment with erlotinib when mutation testing is not feasible.  相似文献   
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