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Cicletanine was tested at different doses (7.5, 10 and 30 mg/kg, p.o.) on young rats showing high blood pressure readings after social deprivation for 7 consecutive days. At all dose levels, the compound produced a statistically significant decrease in systolic blood pressure of isolated but not group-housed rats. In contrast, the drug did not affect the heart rate in any of the cases. Interestingly, cicletanine was only found to enhance urinary excretion at the highest dose assayed. The putative mechanism of the antihypertensive action of the drug at non-diuretic doses is discussed.  相似文献   
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p = 0.0006). Including subjects submitted to complete tumor removal (stages I, II, and IIIA) in a multivariate analysis adjusted for TNM stage and histologic type, bearers of aneuploid tumors exhibited a higher risk of relapse (hazard ratio 2.65; CI 95% 1.5–4.66; p = 0.004) or death (hazard ratio 2.17; CI 95% 1.08–4.39; p = 0.032) than patients with diploid tumors. DNA ploidy resulted an independent prognostic factor of survival and tumor relapse in completely resected non-small-cell lung cancer. Sequential analysis of fresh and paraffin-embedded samples can help avoid the bias due to intratumoral DNA content heterogeneity. DNA ploidy could be an useful parameter in any future multifactorial analysis of outcome in such tumors.  相似文献   
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Background In recent years platinum-based chemotherapy has become the standard of care for patients with good performance status after complete resection in stages IB-IIIA non-small-cell lung cancer (NSCLC), although the benefit is mainly in stages II and IIIA. Patients and methods In a retrospective trial we evaluate the clinical efficacy and toxicity profile of a platinum- and taxanes-based adjuvant chemotherapy in completely resected IB-IIIA NSCLC. The primary end point was relapse- free survival (RFS); principal secondary end points were overall survival (OS) and safety of the regimen. Potential predictive factors of efficacy and clinical patterns of relapse were also analysed. Results From January 2003 to December 2006, 41 patients met the inclusion criteria and were evaluable. Median age at diagnosis was 68.1 years (CI 95% 54-72; range 45-78). Most patients were males (87.7%) and had an Eastern Cooperative Oncology Group performance status score (PS) of 0-1 (87.8%), and 53.6% had adenocarcinomas. Pathological stages were as follow: 48.7% stage IB, 24.3% stage II and 26.8% stage IIIA. 75.6% of patients underwent a lobectomy and mediastinal lymphadenectomy and were treated with a combination of carboplatin AUC6 and paclitaxel 200 mg/m(2) (85.36%) for 3 or 4 cycles. With a median follow-up of 18.2 months (range 5.1-46.5), 26 patients (63%) were free of disease and 32 of them were alive (78%). Median RFS was 12.1 months (CI 95% 9.8-14.9) and median OS had not been reached at the time of analysis. Patients with PS相似文献   
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NSP-interacting kinase (NIK1) is a receptor-like kinase identified as a virulence target of the begomovirus nuclear shuttle protein (NSP). We found that NIK1 undergoes a stepwise pattern of phosphorylation within its activation-loop domain (A-loop) with distinct roles for different threonine residues. Mutations at Thr-474 or Thr-468 impaired autophosphorylation and were defective for kinase activation. In contrast, a mutation at Thr-469 did not impact autophosphorylation and increased substrate phosphorylation, suggesting an inhibitory role for Thr-469 in kinase function. To dissect the functional significance of these results, we used NSP-expressing virus infection as a mechanism to interfere with wild type and mutant NIK1 action in plants. The NIK1 knockout mutant shows enhanced susceptibility to virus infections, a phenotype that could be complemented with ectopic expression of a 35S-NIK1 or 35S-T469A NIK1 transgenes. However, ectopic expression of an inactive kinase or the 35S-T474A NIK1 mutant did not reverse the enhanced susceptibility phenotype of knockout lines, demonstrating that Thr-474 autophosphorylation was needed to transduce a defense response to geminiviruses. Furthermore, mutations at Thr-474 and Thr-469 residues antagonistically affected NIK-mediated nuclear relocation of the downstream effector rpL10. These results establish that NIK1 functions as an authentic defense receptor as it requires activation to elicit a defense response. Our data also suggest a model whereby phosphorylation-dependent activation of a plant receptor-like kinase enables the A-loop to control differentially auto- and substrate phosphorylation.  相似文献   
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Aim: Cholinergic dysfunction is a major neurochemical feature in Alzheimer's disease (AD), accountable for many cognitive dysfunctions and some psychiatric symptoms. Butyrylcholinesterase (BChE) is one of the cholinesterases with increased activity in the brain of Alzheimer's patients. Several mutations code for different BChE, such as the K variant, which is the most common and is capable of reducing BChE activity by 30%. We studied the relationship between this K variant and Alzheimer's disease in our population from the Canary Islands (Spain). Patients and methods: We used DNA PCR-RFLP techniques to compare 282 patients who had been diagnosed with probable Alzheimer's disease – according to NINCS-ADRDA criteria – with 312 control subjects confirmed to be free of cognitive impairment as assessed by using the CAMDEX cognitive subscale CAMCOG. Results: In our population the K variant of BChE is linked to the age of diagnosis of Alzheimer's disease, since AD individuals with this allele presented the disease at a later stage. No other susceptibility relations are exposed in this study. In addition, the BChE allelic frequencies in our population are higher than those previously reported.  相似文献   
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