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BACKGROUND: Hypertension is an important cause of cardiovascular morbidity and mortality. METHODS AND RESULTS: We conducted a cross-sectional survey of 314 middle-aged subjects (163 men; age range 40-60 years, mean 49 years) in urban Thiruvananthapuram City. Kerala, to estimate the prevalence of hypertension, examine its correlates, and assess the degree of awareness, treatment, and control of high blood pressure. Blood pressure was measured by a nurse graduate using a mercury column sphygmomanometer and a standardized technique. We used multivariable analyses to examine the sociodemographic and clinical correlates of hypertension. The overall prevalence of hypertension in our sample was 54.5% (men 56.3%, women 52.3%). The factors associated with an increased prevalence of hypertension were higher body-mass index (odds ratio for a value in the top tertile of 2.33, 95% confidence interval: 1.2-4.4), and older age (odds ratio for the age group 55-60 years of 2.65, 95% confidence interval: 1.3-5.6). An occupation involving moderate or greater physical activity was inversely associated with the prevalence of hypertension (odds ratio 0.35, 95% confidence interval 0.13-0.94). Among hypertensives, 39% were aware of the condition, while 29% were treated with blood pressure-lowering medications. Adequate control of elevated blood pressure was achieved in only 30.6% of treated hypertensives. In our community-based sample, over half of all middle-aged individuals were hypertensive, but less than a third were under treatment. Adequate control of hypertension was achieved in less than a third of the treated individuals. CONCLUSIONS: These observations re-emphasize the need for hypertension awareness programs targeting the general public and the increased use of opportunistic blood pressure screening, and underscore the importance of measures to increase the knowledge of current guidelines for the detection and treatment of hypertension among healthcare providers.  相似文献   
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The primary cilium is an organelle that senses cues in a cell's local environment. Some of these cues constitute molecular signals; here, we investigate the extent to which primary cilia can also sense mechanical stimuli. We used a conditional approach to delete Kif3a in pre-osteoblasts and then employed a motion device that generated a spatial distribution of strain around an intra-osseous implant positioned in the mouse tibia. We correlated interfacial strain fields with cell behaviors ranging from proliferation through all stages of osteogenic differentiation. We found that peri-implant cells in the Col1Cre;Kif3afl/fl mice were unable to proliferate in response to a mechanical stimulus, failed to deposit and then orient collagen fibers to the strain fields caused by implant displacement, and failed to differentiate into bone-forming osteoblasts. Collectively, these data demonstrate that the lack of a functioning primary cilium blunts the normal response of a cell to a defined mechanical stimulus. The ability to manipulate the genetic background of peri-implant cells within the context of a whole, living tissue provides a rare opportunity to explore mechanotransduction from a multi-scale perspective.  相似文献   
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Jankelowitz L  Reid KJ  Wolfe L  Cullina J  Zee PC  Jain M 《Chest》2005,127(5):1593-1599
STUDY OBJECTIVES: Cystic fibrosis (CF) patients may be predisposed to poor sleep quality due to upper and lower airway abnormalities and impaired gas exchange. Previous sleep investigations of CF patients using single-night polysomnography have reported conflicting results. We hypothesized that sampling sleep for a prolonged period in a patient's normal environment may give a more representative assessment of sleep quality than a single-night polysomnogram, and that impaired sleep quality would correlate with pulmonary disease severity and self-assessed sleep quality. DESIGN: Using wrist actigraphy, we measured sleep quality in clinically stable CF patients and age-matched control subjects. In addition, each CF patient and control subject completed the following three questionnaires: the Epworth sleepiness scale; the Pittsburgh sleep quality index (PSQI); and the Medical Outcomes Study 36-item short form. RESULTS: Twenty CF patients and control subjects were enrolled in the study, and were well-matched for age, sex, and body mass index. The mean (+/- SD) FEV(1) for CF patients was 61.0 +/- 20.1% predicted. CF patients and control subjects had similar sleep duration, sleep latency, and sleep efficiency. However, CF patients had higher PSQI scores (6.45 vs 4.55, respectively; p = .04), a higher fragmentation index (FI) [31.72 vs 18.02, respectively; p < 0.001], and less immobile time (88.87 vs 91.89, respectively; p = 0.02). There was a significant correlation of FI with FEV(1) and PSQI scores. CONCLUSIONS: Stable CF patients have disrupted sleep, and sleep disruption may in part be related to the severity of pulmonary disease. In addition, the PSQI may be useful in detecting CF patients with poor sleep quality.  相似文献   
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The performance of biodegradable knitted and rolled 3‐dimensional (3D) polylactide‐based 96/4 scaffolds modified with bioactive glass (BaG) 13‐93, chitosan and both was compared with regard to the viability, proliferation and chondrogenic differentiation of rabbit adipose stem cells (ASCs). Scaffold porosities were determined by micro‐computed tomography (μCT). Water absorption and degradation of scaffolds were studied during 28‐day hydrolysis in Tris‐buffer. Viability, number and differentiation of ASCs in PLA96/4 scaffolds were examined in vitro. The dimensions of the scaffolds were maintained during hydrolysis and mass loss was detected only in the BaG13‐93 containing scaffolds. ASCs adhered and proliferated on each scaffold type. Cell aggregation and expression of chondral matrix components improved in all scaffold types in chondrogenic medium. Signs of hypertrophy were detected in the modified scaffolds but not in the plain PLA96/4 scaffold. Chondrogenic differentiation was most enhanced in the presence of chitosan. These findings indicate that the plain P scaffold provided a good 3D‐matrix for ASC proliferation whereas the addition of chitosan to the PLA96/4 scaffold induced chondrogenic differentiation independent of the medium. Accordingly, a PLA96/4 scaffold modified by chitosan could provide a functional and bioactive basis for tissue‐engineered chondral implants. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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