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171.
PurposeThe prevalence of phenotypes of Arylamine N-acetyltransferase-2(NAT2) gene (i.e. fast, intermediate and slow acetylators) among ethnic groups, as well as the association studies regarding NAT2 polymorphisms and risk of breast cancer produced inconsistent results. This meta-analysis aimed to clarify whether the selected NAT2 phenotypes have an effect on the susceptibility to breast cancer.MethodsAfter aggregating the frequencies of fast, intermediate and slow phenotypes of NAT2 in breast cancer subjects, the odds ratio and relevant 95% confidence intervals were examined using combined data from all published 36 articles.ResultsOverall, our results did not produce statistical significance for the proposed association, suggesting that there is no association between the selected phenotypes of NAT2 polymorphisms and breast cancer. In subgroup analyses, it was revealed that, as compared with the fast phenotype, intermediate acetylator is protective of the vulnerable White population to breast cancer. In addition, an obvious ethnic/geographic difference was found in the prevalence of fast, intermediate and slow acetylators among world-wide populations.ConclusionsAlthough ethnic and geographic differences in NAT2 polymorphisms were present, this was not associated with the risk of breast cancer in general. Intermediate acetylator is protective for particular ethnic groups, a finding which should be carefully viewed and confirmed in the future studies.  相似文献   
172.
In previous presentations to this congress we have reported an increase in intelligibility of isolated words at poor signal-to-noise ratios when the phase angle differences between the ears were adjusted to certain values. Question has arisen as to whether this phenomenon is one of a peculiar property of speech or one of that kind usually called release from masking. Therefore, a study was done to compare normal voiced speech with whispered speech at a signal-to-noise ratio of 0 dB and subject to various phase angle differences between the ears. Data are presented which suggest that the apparent release from masking may be due in part to properties of voice, but not entirely so.  相似文献   
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Objective The study was to provide information on quantitative sensory testing (QST) of normal teeth to establish a sensory profile and investigate the possible gender and regional differences. Materials and methods A modified QST protocol was applied on both left and right upper-jaw incisors and pre-molar sof 14 healthy men and 14 age-matched healthy women (18–25 years). Mechanical stimulus sensitivity (MSS), cold detection threshold (CDT), cold pain threshold (CPT), warm detection threshold (WDT), heat pain threshold (HPT), electrical detection threshold (EDT) and electrical pain threshold (EPT) were determined from the four teeth (labial side of incisor and buccal side of the first premolar). The QST parameters were analysed by ANOVA. Results The applied mechanical or thermal stimuli did not evoke any pain sensation. A normal tooth did not seem to be able to distinguish between the warm or cold stimuli applied. No significant differences were found between genders (p?>?0.099) or teeth (p?>?0.053) regarding mechanical and thermal stimuli. The EDT and EPT were significantly higher in the pre-molar compared with incisor (p?p?>?0.573). Conclusion: The established methods and results provided important information on diagnosis and treatment evaluation of dentinal hypersensitivity.  相似文献   
175.
《Indian heart journal》2018,70(3):360-367
ObjectiveThere are no community based, longitudinal, intra individual epidemiological studies on effect of weather and season on blood pressure (BP). We evaluated the effect of season and temperature on prevalence and epidemiology of BP in tropical climate.Methods and resultsIt was a longitudinal cross sectional survey of rural and urban subjects in their native surroundings. BP was measured in four different seasons in same subjects. A total of 978 subjects (452 rural and 521 urban) were included in the current analysis. Demographic characteristics such as age, gender, education, occupational based physical activity and body mass index (BMI) were recorded. Mean BP, both systolic and diastolic were significantly higher in winter season as compared to summer season. Mean difference between winter and summer was 9.01 (95% CI: 7.74–10.28, p < 0.001) in systolic BP and 5.61 (95% CI: 4.75–6.47, p < 0.001) in diastolic BP. This increase in BP was more marked in rural areas and elderly subjects. Prevalence of hypertension was significantly higher during winter (23.72%) than in summer (10.12%).ConclusionBP increases significantly during winter season as compared to summer season. Increase is more marked in rural areas and elderly subjects. Seasonal variation in BP should be taken into account while looking at prevalence of hypertension in epidemiological studies.  相似文献   
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Spring compliance is perceived by combining the sensed force exerted by the spring with the displacement caused by the action (sensed through vision and proprioception). We investigated the effect of delay of visual and force information with respect to proprioception to understand how visual-haptic perception of compliance is achieved. First, we confirm an earlier result that force delay increases perceived compliance. Furthermore, we find that perceived compliance decreases with a delay in the visual information. These effects of delay on perceived compliance would not be present if the perceptual system would utilize all force-displacement information available during the interaction. Both delays generate a bias in compliance which is opposite in the loading and unloading phases of the interaction. To explain these findings, we propose that information during the loading phase of the spring displacement is weighted more than information obtained during unloading. We confirm this hypothesis by showing that sensitivity to compliance during loading movements is much higher than during unloading movements. Moreover, we show that visual and proprioceptive information about the hand position are used for compliance perception depending on the sensitivity to compliance. Finally, by analyzing participants’ movements we show that these two factors (loading/unloading and reliability) account for the change in perceived compliance due to visual and force delays.  相似文献   
179.
ObjectivesDetermining the minimal clinically important difference (MCID) of questionnaires on an interval scale, the trait level (TL) scale, using item response theory (IRT) models could overcome its association with baseline severity. The aim of this study was to compare the sensitivity (Se), specificity (Sp), and predictive values (PVs) of the MCID determined on the score scale (MCID-Sc) or the TL scale (MCID-TL).Study Design and SettingThe MCID-Sc and MCID-TL of the MOS-SF36 general health subscale were determined for deterioration and improvement on a cohort of 1,170 patients using an anchor-based method and a partial credit model. The Se, Sp, and PV were calculated using the global rating of change (the anchor) as the gold standard test.ResultsThe MCID-Sc magnitude was smaller for improvement (1.58 points) than for deterioration (−7.91 points). The Se, Sp, and PV were similar for MCID-Sc and MCID-TL in both cases. However, if the MCID was defined on the score scale as a function of a range of baseline scores, its Se, Sp, and PV were consistently higher.ConclusionThis study reinforces the recommendations concerning the use of an MCID-Sc defined as a function of a range of baseline scores.  相似文献   
180.
《COPD》2013,10(1):125-129
Simple walking tests are widely used for the assessment of functional status in patients with cardiorespiratory disorders. These tests require far less instrumentation than formal cardiopulmonary exercise tests, but they do require standardization of procedures to achieve reproducible results. The most widely used tests for patients with COPD are the 6-minute walking test (6MWT) and the incremental shuttle walking test (SWT). The 6MWT has been characterized in COPD patients with respect to reproducibility and responsivity to change in health status. The 6MWT results are correlated with pulmonary function, health-related quality of life, maximum exercise capacity, and mortality. The minimal clinically important difference (MCID) for the 6MWT is conservatively estimated to be 54–80 meters using both distributional and discriminative methods. For an individual patient, the 6MWT would need to change by about 86 meters to be statistically confident that there has been a change. The SWT has been less extensively validated than the 6MWT, but has similar reproducibility in COPD (CV = approximately 20%). The SWT results improve with pulmonary rehabilitation and bronchodilation, and are highly correlated with maximum oxygen consumption. There are no studies that address the issue of MCID for the SWT. In addition to the MCID, the design and interpretation of COPD clinical trials should take into account the severity of initial impairment, the asymmetry between positive and negative changes, the proportion of patients who show substantial improvement, and the costs and risks of the treatment.  相似文献   
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