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993.
The demographic and practice-related characteristics of physicians who use social networking websites, portable devices to access the internet, email to communicate with patients, podcasts, widgets, RSS feeds, and blogging were investigated. Logistic regression was used to analyze a survey of US primary care physicians, pediatricians, obstetrician/gynecologists, and dermatologists (N=1750). Reported technology use during the last 6 months ranged from 80.6% using a portable device to access the internet to 12.9% writing a blog. The most consistent predictors of use were being male, being younger, and having teaching hospital privileges. Physician specialty, practice setting, years in practice, average number of patients treated per week, and number of physicians in practice were found to be inconsistently associated or unassociated with use of the technologies examined. Demographic characteristics, rather than practice-related characteristics, were more consistent predictors of physician use of seven internet-based communication technologies with varying levels of uptake.  相似文献   
994.
CONTEXT: Despite theoretical concerns that health care related distrust may lead to poor health outcomes by interfering with effective health care, little is currently known about the prevalence or outcomes of distrust of the health care system in the United States.
OBJECTIVE: To investigate the association between distrust of the health care system and self-reported health status among the general population in the United States.
DESIGN: Random-digit-dialing telephone survey.
PARTICIPANTS: Nine hundred and sixty-one adult residents of the continental U.S.
PRIMARY MEASURES: Distrust of the health care system and self-reported health status.
RESULTS: Distrust of the health care system is relatively high in the United States, with between 20% and 80% of respondents reporting distrust for each item on the Health Care System Distrust scale and a median scale score of 31 (potential range from 10 to 50). Distrust of the health care system is strongly associated with self-reported fair/poor health (odds ratio [OR] 1.40%, 95% confidence interval [CI] 1.12 to 1.75 for each standard deviation increase in distrust), even after adjusting for sociodemographic characteristics, access to health care and trust in primary physicians. In contrast, low trust in one's primary physician is much lower (only 10% to 20% of respondents reported distrust for each item) and is not associated with health status.
CONCLUSIONS: Distrust of the health care system is relatively high in the general population in the United States and is strongly associated with worse self-reported health. Further studies are needed to assess the direction of this association and the mechanisms involved.  相似文献   
995.
A high incidence of noncompliance to prescribed treatment plans results in increased morbidity, hospitalizations, and mortality rates in patients with heart failure. Exploration of new avenues to encourage adherence is needed in nursing research. The purpose of this study was to explore whether a relationship existed between spirituality and compliance in patients with heart failure. The Spiritual Assessment Scale and the Heart Failure Compliance Questionnaire Revised were mailed to a convenience sample with a return response from 95 participants. Although mean scores for the Spiritual Assessment Scale and the Heart Failure Compliance Questionnaire Revised were high, data suggested no correlation existed between levels of spirituality and degree of compliance among the heart failure participants, r=16393; p=0.115. Although insignificant results were found between levels of spirituality and degree of compliance, the data did not rule out the importance of spirituality as a coping tool.  相似文献   
996.
Aim: To explore weight status perception and its relation to actual weight status in a contemporary cohort of 5‐ to 17‐year‐old children and adolescents. Methods: Body mass index (BMI), derived from height and weight measurements, and perception of weight status (‘too thin’, ‘about right’ and ‘too fat’) were evaluated in 3043 participants from the Healthy Kids Queensland Survey. In children less than 12 years of age, weight status perception was obtained from the parents, whereas the adolescents self‐reported their perceived weight status. Results: Compared with measured weight status by established BMI cut‐offs, just over 20% of parents underestimated their child's weight status and only 1% overestimated. Adolescent boys were more likely to underestimate their weight status compared with girls (26.4% vs. 10.2%, P < 0.05) whereas adolescent girls were more likely to overestimate than underestimate (11.8% vs. 3.4%, P < 0.05). Underestimation was greater by parents of overweight children compared with those of obese children, but still less than 50% of parents identified their obese child as ‘too fat’. There was greater recognition of overweight status in the adolescents, with 83% of those who were obese reporting they were ‘too fat’. Conclusion: Whilst there was a high degree of accuracy of weight status perception in those of healthy weight, there was considerable underestimation of weight status, particularly by parents of children who were overweight or obese. Strategies are required that enable parents to identify what a healthy weight looks like and help them understand when intervention is needed to prevent further weight gain as the child gets older.  相似文献   
997.
BACKGROUND & AIMS: Most patients with extreme obesity have nonalcoholic fatty liver disease (NAFLD). Although gastric bypass (GBP) surgery is the most common bariatric operation performed in obese patients in the United States, the effect of GBP surgery-induced weight loss on the metabolic and hepatic abnormalities associated with NAFLD are not clear. METHODS: Whole-body glucose, fatty acid and lipoprotein kinetics, liver histology, and hepatic cellular factors involved in inflammation and fibrogenesis were evaluated in 7 extremely obese subjects (body mass index, 58 +/- 4 kg/m(2)) before and 1 year after GBP surgery. RESULTS: At 1 year after surgery, subjects lost 29% +/- 5% of initial body weight (P < .01); palmitate rate of appearance in plasma, an index of adipose tissue lipolysis, decreased by 47% +/- 4% (P < .01); endogenous glucose production rate decreased by 27% +/- 7% (P < .01); and very-low-density lipoprotein-triglyceride secretion rate decreased by 44% +/- 9% (P < .05). In addition, GBP surgery-induced weight loss decreased hepatic steatosis but did not change standard histologic assessments of inflammation and fibrosis. However, there was a marked decrease in hepatic factors involved in regulating fibrogenesis (collagen-alpha1(I), transforming growth factor-beta1, alpha-smooth muscle actin, and tissue inhibitor of metalloproteinase 1 expression and alpha-smooth muscle actin content) and inflammation (macrophage chemoattractant protein 1 and interleukin 8 expression) (P < .05, compared with values before weight loss). CONCLUSIONS: These data demonstrate that weight loss induced by GBP surgery normalizes the metabolic abnormalities involved in the pathogenesis and pathophysiology of NAFLD and decreases the hepatic expression of factors involved in the progression of liver inflammation and fibrosis.  相似文献   
998.
Nod1, a cytosolic protein that senses meso-diaminopimelic acid-containing ligands derived from peptidoglycan, plays a role in host responses to invasive bacteria. Here we describe a function for Nod1, whereby it controls tumor formation. Cell lines derived from the human breast cancer epithelial cell line MCF-7 were used in a severe combined immune deficiency (SCID) mouse xenograft model to characterize a pathway linking Nod1 to the growth of estrogen-sensitive tumors. In MCF-7 cells, the absence of Nod1 correlates with tumor growth, an increased sensitivity to estrogen-induced cell proliferation, and a failure to undergo Nod1-dependent apoptosis. Conversely, overexpression of Nod1 in MCF-7 cells results in inhibition of estrogen-dependent tumor growth and reduction of estrogen-induced proliferative responses in vitro.  相似文献   
999.
Mineralocorticoid receptor antagonists protect against ischemic cerebrovascular disease; this appears to be caused by changes in cerebral vessel structure that would promote blood flow. Therefore, we hypothesized that mineralocorticoid receptor activation with deoxycorticosterone acetate would cause deleterious remodeling of the cerebral vasculature and exacerbate the damage caused by cerebral ischemia. Six-week-old male Wistar rats were treated with deoxycorticosterone acetate (200 mg/kg) for 6 weeks. At 12 weeks of age, the deoxycorticosterone acetate-treated rats had elevated systolic blood pressure compared with age-matched controls (157+/-5.9 versus 124+/-3.1 mm Hg deoxycorticosterone acetate versus control; P<0.05). The area of ischemic damage resulting from middle cerebral artery occlusion was greater in the deoxycorticosterone acetate-treated rats than control (63.5+/-3.72 versus 46.6+/-5.52% of the hemisphere infarcted, deoxycorticosterone acetate versus control; P<0.05). Middle cerebral artery structure was assessed using a pressurized arteriograph under calcium-free conditions. Over a range of intralumenal pressures, the lumen and ODs of the middle cerebral arteries were smaller in the deoxycorticosterone acetate-treated rats than the control rats (P<0.05). There was also an increase in the wall thickness and wall:lumen ratio in the vessels from deoxycorticosterone acetate-treated rats (P<0.05). The vessels from the deoxycorticosterone acetate-treated rats were stiffer than those from control rats as evidenced by a leftward shift in the stress/strain curve. These novel data suggest that mineralocorticoid receptor activation without salt loading and nephrectomy is sufficient to elicit deleterious effects on the cerebral vasculature that lead to inward hypertrophic remodeling and an increase in the ischemic damage in the event of a stroke.  相似文献   
1000.
Conventional electrophysiological intracellular recording techniques were used to test the hypothesis that enhanced calcium entry via voltage-gated calcium channels or theN-methyl-d-aspartate (NMDA) subtype of glutamate receptor–channel complex may be a primary pathological mechanism triggering neurodegeneration in scrapie and related diseases. This study was carried out at a time when cell loss is known to occur and when hippocampal pyramidal cells in area CA1 are rendered hyperexcitable following scrapie infection. There was no change to the NMDA receptor-mediated component of the Schäffer collateral evoked excitatory postsynaptic potential (EPSP) or the level of spontaneous firing activity of CA1 cells following addition of the specific NMDA receptor antagonist, 2-amino-5-phosphonovaleric acid (APV, 20 μM), to the perfusate in scrapie-infected mice, indicating that the NMDA receptor–channel complex is not compromised by scrapie. There was also no change seen in the non-NMDA mediated component of the EPSP. The calcium spike of CA1 pyramidal cells was not significantly altered by scrapie infection, indicating that high threshold voltage-gated Ca2+channel function is not compromised by scrapie. By contrast, cells from scrapie-infected mice fired calcium spikes repetitively and the long, slow AHP, which in control cells inhibited repetitive firing, was absent. Cells from scrapie-infected mice showed more depolarized membrane potentials than controls but this difference in potential was no longer observed after exposure to TEA. These data indicate a loss of TEA-insensitive and TEA-sensitive potassium conductances. We suggest that altered potassium currents rather than increased calcium entry via voltage-sensitive calcium channels or the NMDA receptor complex may be the primary pathological mechanism triggering neurodegeneration in scrapie and related diseases.  相似文献   
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