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41.
BACKGROUND: An association between midlife blood pressure levels and late-life cognitive impairment has been reported. Hypertension is one of the most important factors related to the presence of cerebral white matter lesions, which is a prognostic factor for the development of cognitive impairment. Studies have shown a relationship between white matter lesions and cognitive decline in elderly hypertensive patients. The aim of the present study was to evaluate cognitive function in asymptomatic middle-aged hypertensive patients according to the presence or absence of white matter lesions. METHODS: Sixty never-treated essential hypertensive patients (38 men, 22 women), aged 50 to 60 years (mean age, 54.4 +/- 3.8 years), without clinical evidence of target organ damage, were studied. All patients underwent brain magnetic resonance imaging to establish the presence or absence of white matter lesions, using the Rotterdam criteria. Cognitive function was evaluated by a neuropsychologic test battery measuring attention, memory, intelligence, anxiety, and depression. RESULTS: Twenty-three hypertensive patients (38%) were found to have white matter lesions on brain resonance. These patients exhibited a significantly worse performance on digit span forward, a standardized measure of attention than hypertensives without white matter lesions (4.86 +/- 1.14 v 5.51 +/- 0.97; P =.027). Hypertensive patients with white matter lesions showed no differences on both visual and logical memory tests when compared with patients without lesions. CONCLUSIONS: We conclude that the presence of silent cerebral white matter lesions in middle-aged hypertensive patients is associated with a mild decline in basic attention.  相似文献   
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Endothelial function is thought to be an important factor in the pathogenesis of atherosclerosis, hypertension and heart failure. In the 1990s, high-frequency ultrasonographic imaging of the brachial artery to assess endothelium-dependent flow-mediated vasodilation (FMD) was developed. The technique provokes the release of nitric oxide, resulting in vasodilation that can be quantitated as an index of vasomotor function. The noninvasive nature of the technique allows repeated measurements over time to study the effectiveness of various interventions that may affect vascular health. However, despite its widespread use, there are technical and interpretive limitations of this technique. State-of-the-art information is presented and insights are provided into the strengths and limitations of high-resolution ultrasonography of the brachial artery to evaluate vasomotor function, with guidelines for its research application in the study of endothelial physiology.  相似文献   
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OBJECTIVE: This study was designed to determine whether antisense oligodeoxynucleotides (ODN) directed against the nuclear proto-oncogene c-myc could inhibit restenosis when given by local delivery immediately after coronary stent implantation. BACKGROUND: Failure of conventional pharmacologic therapies to reduce the incidence of coronary restenosis after percutaneous revascularization techniques has prompted interest in the use of agents that target intracellular central regulatory mechanisms. METHODS: Eighty-five patients were randomly assigned to receive either 10 mg of phosphorothioate-modified 15-mer antisense ODN or saline vehicle by intracoronary local delivery after coronary stent implantation. The primary end point was percent neointimal volume obstruction measured by computerized analysis of electrocardiogram-gated intravascular ultrasound (IVUS) at six-month follow-up. Secondary end points included clinical outcome and quantitative coronary angiography analysis. RESULTS: Analysis of follow-up IVUS data was performed on 77 patients. In-stent volume obstruction was similar between groups (44 +/- 16% and 46 +/- 14%, placebo vs. ODN; p = 0.57; 95% confidence interval: -1.13 to 0.85). Minimum luminal diameter increased from 0.84 +/- 0.36 and 0.90 +/- 0.45 (p = 0.55) to 2.70 +/- 0.37 and 2.80 +/- 0.37 (p = 0.28) after stent implantation, which decreased to 1.50 +/- 0.61 and 1.50 +/- 0.53 (p = 0.98) by six months, yielding similar loss indexes (placebo vs. ODN, respectively). There were no differences in angiographic restenosis rates (38.5 and 34.2%; p = 0.81; placebo vs. ODN) or clinical outcome. CONCLUSIONS: Treatment with 10 mg of phosphorothioate-modified ODN directed against c-myc does not reduce neointimal volume obstruction or the angiographic restenosis rate in this patient population.  相似文献   
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Helical computerized tomography (CT) and magnetic resonance imaging (MRI) are used for staging of hepatocellular carcinoma (HCC) prior to curative treatments but underestimate tumor extension in 30% to 50% of cases when compared with pathologic explants. This study compares a new technology, MRI angiography (MRA), with triphasic helical CT in detection of HCC. Fifty cirrhotic patients, 29 with HCC, undergoing liver transplantation were analyzed. MRA was performed with a 3-D breath-hold fast spoiled gradient-echo sequence by using an effective section thickness of 2 to 2.5 mm. The gold standard was the pathologic examination (liver cut into 5-mm slices). One hundred twenty-seven lesions were identified at the explant: 76 HCC, 13 high-grade dysplastic nodules, 31 macroregenerative nodules, 7 hemangiomas. Diameter of the main HCC nodules was 29 +/- 14 mm and 11 +/- 7 mm for the 47 additional nodules. On a per nodule basis, sensitivity of MRA was superior to CT (58/76 [76%] vs. 43/70 [61%], respectively, P =.001). Sensitivity of MRA for detection of additional nodules decreased with size (>20 mm: 6/6 [100%]; 10-20 mm: 16/19 [84%]; <10 mm: 7/22 [32%]) and was superior to CT for nodules 10 to 20 mm (84% vs. 47%, P =.016). Nonspecific hypervascular nodules >5 mm at MRA were HCC in two thirds of the cases. In conclusion, MRA has a high diagnostic accuracy for HCC > or =10 mm and is more sensitive than triphasic helical CT in nodules sized 10 to 20 mm. MRA is the optimal technique for HCC staging prior to curative therapies.  相似文献   
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To identify new candidate anticancer compounds, we here report the synthesis of benzimidazole derivatives: diethyl 2,2′-(2-oxo-1H-benzo[d]imidazole-1,3(2H)-diyl) diacetate and its arylideneacetohydrazide derivatives, using ultrasonic irradiation and conventional heating. The compounds were confirmed by Nuclear magnetic resonance (NMR) (JEOL, Tokyo, Japan) and Fourier transform infrared spectroscopy (FTIR) spectroscopy (Thermoscientific, Waltham, MA, USA). The molecular structure and electronic properties of the studied compounds were predicted for the acetohydrazide hydrazones. These compounds exist as a mixture of configurational and conformational isomerism as well as amido-amidic acid tautomerism. The NMR spectral data proved the predominance of syn-E amido isomers. In addition, density functional theory (DFT) predicted stability in the gas phase and showed that syn-E amido isomers are the most stable in the presence of an electron donating group, while the anti-isomer is the most stable in the presence of electron-attracting substituents. The anticancer activity of these synthetic compounds 6a, 6b and 6c towards both colon cancer (HCT-116) and cervical cancer (HeLa) cells was examined by MTT assay and DAPI staining. The MTT assay revealed a strong antiproliferative effect against the cancer cells at low concentrations, and interestingly, no significant inhibitory action against the non-cancerous cell line, HEK-293. The IC50 values for HCT-116 were 29.5 + 4.53 µM, 57.9 + 7.01 µM and 40.6 + 5.42 µM for 6a, 6b, and 6c, respectively. The IC50 values for HeLa cells were 57.1 + 6.7 µM, 65.6 + 6.63 µM and 33.8 + 3.54 µM for 6a, 6b, and 6c, respectively. DAPI staining revealed that these synthesized benzimidazole derivatives caused apoptotic cell death in both the colon and cervical cancer cells. Thus, these synthetic compounds demonstrate encouraging anticancer activity as well as being safe for normal human cells, making them attractive candidates as anticancer agents.  相似文献   
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Given the increase in life expectancy indeveloped countries,nonagenarian population will become clinically and numerically relevant in our daily routine practice in the near future.Age has been observed to exert a profound influence on the prevalence of severe mitral regurgitation (MR) in the population.[1]Mitral valve surgery remains the gold standard of care for patients with symptomatic severe MR.  相似文献   
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Our objective was to investigate the prevalence and the environmental determinants of alcohol use among students in the region of Sfax in Tunisia. We carried out a cross-sectional study among 315 middle and high school students. We used the Alcohol Use Disorders Identification Test (AUDIT) to identify risky alcohol consumption, and we used the Parenting Styles and Dimensions Questionnaire (PSDQ) to assess the students’ perceptions of their parents’ parenting styles. The results show that 19.7% reported drinking alcohol at least once in their lifetime. Among them, 21% scored as dependent alcohol users, according to the AUDIT. Those who drank alcohol at least once were more likely to have parents with a permissive parenting style (p < 0.001; Cramer’s V = 0.287), and a father (p < 0.001; Cramer’s V = 0.258), a mother (p = 0.025; Cramer’s V = 0.158), or a friend (p < 0.001; Cramer’s V = 0.341) who drinks. Students perceiving their parents’ parenting style as permissive had the highest AUDIT score (p = 0.005; partial η2 = 0.132). The authoritarian style score was significantly higher for students who were current alcohol users (p = 0.028; Cohen’s d = 0.57). Our study highlights the influence of peers, family drinking, and parenting styles on alcohol use among middle and high school students. Therefore, particular attention should be given to students that are at risk of having the abovementioned environmental determinants of alcohol use. And, prevention strategies should involve parents, as well as enhanced guidance and counseling for these students.

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