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We investigated the relationship of pessimistic attributional style (specifically, stable attributions for negative events) and socioeconomic status (SES) to cardiovascular and catecholamine profiles in a biracial sample of 37 postmenopausal women (aged 39-64 years) not taking hormone replacement therapy (HRT). Blood pressure (BP) variation in response to the demands of daily life was assessed by 24-hour ambulatory monitoring on a typical workday. Subjects were classified into groups by stable pessimistic attributions (high vs. low pessimism) and by SES (high vs. low). Significant SES x pessimism interactions were found. Low SES/high pessimism women demonstrated higher systolic BP (SBP) during the day, evening, and sleep periods of 24-hour ambulatory monitoring compared with the other three groups. A greater proportion of this group was in the hypertensive range (> or = 140/90 mm Hg) compared with the other groups (57% vs. 8%-29%). Low SES/high pessimism women also reported reduced available social support compared with the other three groups.  相似文献   
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BACKGROUND: The role of acid in the pathogenesis of indomethacin- induced ulcers of the rat gastric antrum was studied by comparing the effects of pretreating animals with both long-acting (loxtidine, AH22216) and short-acting (ranitidine and cimetidine) inhibitors of acid secretion. RESULTS: Ranitidine and cimetidine were much weaker at inhibiting antral damage when compared to their reported potencies as antisecretory agents. In marked contrast, loxtidine and AH22216 inhibited indomethacin-induced antral ulcers at doses similar to their reported potencies as inhibitors of acid secretion. Histological analysis at doses causing near maximal inhibition of macroscopic damage revealed an almost complete absence of ulcers but a large and significant increase in mucosal damage due to superficial erosions. Hourly dosing with hydrochloric acid reversed the protective effect of ranitidine, cimetidine and loxtidine on macroscopic damage and, histologically, this was associated with the widespread appearance of antral ulcers and a reduction in the proportion of mucosal damage caused by superficial erosions. CONCLUSIONS: The results of this study suggest that the pathogenesis of nonsteroidal anti-inflammatory drug (NSAID)-induced antral ulcers involves at least two stages: (1) an initial acid-independent formation of mucosal erosions followed by (2) an acid-dependent conversion of erosions to frank ulcers. Clinically, drugs that suppress acid completely for long periods may be very effective in preventing NSAID-induced gastric antral ulcers.  相似文献   
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PURPOSE: This study examines the acute effects of moderate aerobic exercise on 1) hemodynamic and sympathetic activity during behavioral stress and 2) beta-adrenergic receptor responsivity in a biracial sample of 24 sedentary adults. METHODS: Before and after exercise, blood pressure (BP), impedance-derived cardiovascular measures, and plasma norepinephrine (NE) and epinephrine (EPI) were assessed during mental arithmetic and active speech tasks, and beta-adrenergic receptor responsivity was assessed using a standard isoproterenol challenge procedure. RESULTS: After exercise, BP, NE, and EPI responses to stress were reduced (0.0001 < P < 0.08), preejection period (PEP) was elongated (P < 0.0001), and beta(1)- and beta(2)-receptor responsivity (P < 0.02) was enhanced. Approximately 65% of the prepost exercise mean arterial pressure response difference could be accounted for by changes in sympathetic factors, with change in NE and PEP being the single best predictors. CONCLUSIONS: Reduced BP responses to stress after acute exercise are strongly linked to a decrease in sympathetic drive, as evidenced by reduced NE responses and elongation of the PEP. Coincident with this overall dampening of the hemodynamic response to stress, increases in cardiac and vascular beta-adrenergic receptor responsivity occur. These findings may have important implications for future translational studies that seek to articulate the mechanisms through which regular aerobic exercise reduces the risks of hypertensive and coronary heart disease.  相似文献   
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Background

The identification of live cells using membrane integrity dyes has become a frequently used technique, especially with articular cartilage and chondrocytes in situ where tissue slices are used to assess cell recovery as a function of location. The development of a reproducible computerised method of cell evaluation would eliminate many variables associated with manual counting and significantly reduce the amount of time required to evaluate experimental results.

Methods

To validate a custom computerised counting program, intra-person and inter-person cell counts of nine human evaluators (three groups – unskilled, novice, and experienced) were compared with repeated pixel counts of the custom program on 15 digitised images (in triplicate) of chondrocytes in situ stained with fluorescent dyes.

Results

Results indicated increased reproducibility with increased experience within evaluators [Intraclass Correlation Coefficient (ICC) range = 0.67 (unskilled) to 0.99 (experienced)] and between evaluators [ICC = 0.47 (unskilled), 0.85 (novice), 0.93 (experienced)]. The computer program had perfect reproducibility (ICC = 1.0). There was a significant relationship between the average of the experienced evaluators results and the custom program results (ICC = 0.77).

Conclusions

This study demonstrated that increased experience in cell counting resulted in increased reproducibility both within and between human evaluators but confirmed that the computer program was the most reproducible. There was a good correlation between the intact cell recovery determined by the computer program and the experienced human evaluators. The results of this study showed that the computer counting program was a reproducible tool to evaluate intact cell recovery after use of membrane integrity dyes on chondrocytes in situ. This and the significant decrease in the time used to count the cells by the computer program advocate its use in future studies because it has significant advantages.
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Vulvodynia affects 25% of women with painful bladder syndrome/interstitial cystitis (PBS/IC). The objective of our study was to clinically evaluate the association of PBS/IC and vulvodynia and possible contributing factors. To our knowledge, this has not been reported. Seventy women with PBS/IC were evaluated from December 2005 to December 2006 with a comprehensive history and exam. Two groups were formed—those with vulvodynia and those without vulvodynia for comparison. Of the women, 51.4% had vulvodynia and 48.6% did not have vulvodynia using our operative definition. Average levator pain levels were significantly greater in those with vulvodynia. There was no significant difference in the total number of lifetime pelvic surgeries, history of sexually transmitted infections (STIs), vaginitis, or abuse history between groups. The correlation of vulvodynia and PBS/IC may have been underestimated. Research needs to explore the link between precipitating factors, symptoms, and effective treatment options for PBS/IC and vulvodynia.  相似文献   
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