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31.
BACKGROUND: High-risk strategies for the prevention of cardiovascular disease (CVD) among hypertensive patients require knowledge of the prevalence and interaction of modifiable risk factors to ensure effective targeting of interventions. Comparatively little is known of risk-factor profiles and their modification among hypertensives in primary care. AIM: The present study was designed to explore relationships between patients' knowledge of CVD risk factors, their perception of personal risk and health behaviours, and their use of lifestyle interventions. METHOD: A cross-sectional survey of 2676 men and women with mild to moderate hypertension (diastolic blood pressure 95-115 mmHg), and their general practitioners, recruited from 1044 general practices throughout the UK, was conducted. RESULTS: Levels of modifiable risk factors were high, although there was considerable variation by age and sex; most (98.5%) patients had at least one additional CVD risk factor. A lower standard of living was associated with a higher prevalence of 'unhealthy' behaviours. Out of those with a current lifestyle problem, 85% of obese patients, 59% of smokers, 47% of excess drinkers, 49% of those with dietary risk factors and 32% of inactive patients claimed to have adopted healthier behaviours within the past 3 months. Older subjects and those with a lower standard of living were less likely to acknowledge risks, and those who did were less likely to report improving their lifestyles. While 71% of patients recalled receiving lifestyle advice, the coverage and targeting of specific interventions was generally poor. Overall, 60% of the sample had received advice on weight control, 47% on diet, 38% on exercise, 38% on smoking and 36% on alcohol. Women and older people were less likely to be given relevant counseling, and there was no evidence of targeting with respect to subjects' social class, level of hypertension or duration of diagnosis. CONCLUSION: Lifestyle interventions are welcomed and are viewed as helpful by patients receiving them. Potential health gains among high-risk hypertensives are being lost because of poor targeting and coverage of those at greatest risk.  相似文献   
32.
Exercise induces free oxygen radicals that cause oxidative stress, and metallothioneins (MTs) are increased in states of oxidative stress and possess anti-apoptotic effects. We therefore studied expression of the antioxidant factors metallothionein I and II (MT-I + II) in muscle biopsies obtained in response to 3 h of bicycle exercise performed by healthy men and in resting controls. Both MT-I + II proteins and MT-II mRNA expression increased significantly in both type I and II muscle fibres after exercise. Moreover, 24 h after exercise the levels of MT-II mRNA and MT-I + II proteins were still highly increased and the MT-II mRNA expression reached a 15-fold increase. As expected, immunohistochemical detection of malondialdehyde (MDA) and nitrotyrosine (NITT) showed that formation of free radicals and oxidative stress were clearly increased in exercising muscle peaking shortly after the end of exercise in both type I and II muscle fibres. This is the first report demonstrating that MT-I + II are significantly induced in human skeletal muscle fibres following exercise. As MT-I + II are antioxidant factors that protect various tissues during pathological conditions, the MT-I + II increases post exercise may represent a mechanism whereby contracting muscle fibres are protected against cellular stress and injury.  相似文献   
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This study examined sociodemographic, behavioral and psychosocial factors associated with BMI, weight perceptions and trying to lose weight among African-American smokers (N=600, M=44.2 years, 70% female). Sixty-eight percent of the sample were overweight or obese (sample BMI M=28.0, SD=6.7). Three separate, simultaneous multivariable regression models were used to determine which factors were associated with BMI, weight perceptions and trying to lose weight. Poorer health, female gender and high-school education or higher were significantly associated with higher BMIs (p<0.05). Being female (OR=5.8, 95% CI=3.6-9.3) and having a higher BMI (OR=0.6, 95% CI=0.5-0.6) was associated with perception of overweight and smoking more cigarettes per day (OR=1.0, 95% CI=1.0-1.1), and perceiving oneself as overweight (OR=14.1, 95% CI=8.2-24.2) was associated with trying to lose weight. Participants somewhat underestimated their BMI in their weight perceptions. Those who perceived themselves as overweight were more likely to be trying to lose weight; therefore, increasing participant awareness of actual BMI status may lead to improved weight-control efforts in African-American smokers. Several expected associations with outcomes were not found, suggesting that BMI and weight constructs are not well-understood in this population.  相似文献   
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Nephrotic syndrome, characterized by edema, proteinuria, hyperlipidemia and low serum albumin, is a manifestation of kidney disease involving the glomeruli. Nephrotic syndrome may be caused by primary kidney disease such as focal segmental glomerulosclerosis. Mutations in the podocin gene, NPHS2, have been shown in familial and sporadic forms of steroid-resistant nephrotic syndrome, including focal segmental glomerulosclerosis. Podocin is an integral membrane protein located at the slit diaphragm of the glomerular permeability barrier. Complete information is lacking for the population frequency of some NPHS2 variants for all racial and ethnic groups. The most frequently reported variant, R229Q, is more common among European-derived populations than African-derived populations. We calculated crude odds ratios and 95% confidence intervals of childhood nephrotic syndrome and focal segmental glomerulosclerosis associated with R229Q heterozygosity using data from five studies. The R229Q variant is not associated with focal segmental glomerulosclerosis in the US population of African descent. In contrast, the R229Q variant is associated with a trend toward increased focal segmental glomerulosclerosis risk in European-derived populations, with an estimated increased risk of 20-40%. Our insight into the association between NPHS2 variants and nephrotic disease is hampered by the limitations of the existing studies, including small numbers of affected individuals and suboptimal control groups. Nevertheless, the available data suggest that large epidemiological case-control studies to examine the association between NPHS2 variants and nephrotic syndrome are warranted.  相似文献   
38.
Position and intensities of the 13C NMR signals and relaxation times T1 of several anionic and cationic polyelectrolytes in the solid state were compared with those of the appropriate polyanion-polycation complexes. At a high charge density of the components, the most significant changes of the parameters in question due to complex formation are observed for the C atoms adjacent to the charge centers, indicating a strong Coulombic interaction. At lower charge density, conformational changes of the polymer chains have also to be taken into consideration.  相似文献   
39.
To examine whether glucose ingestion during exercise affects the release of interleukin-6 (IL-6) from the contracting limb, seven men performed 120 min of semi-recumbent cycling on two occasions while ingesting either 250 ml of a 6.4 % carbohydrate (GLU trial) or sweet placebo (CON trial) beverage at the onset of, and at 15 min intervals throughout, exercise. Muscle biopsies obtained before and immediately after exercise were analysed for glycogen and IL-6 mRNA expression. Blood samples were simultaneously obtained from a brachial artery and a femoral vein prior to and during exercise and leg blood flow was measured by thermodilution in the femoral vein. Net leg IL-6 release, and net leg glucose and free fatty acid (FFA) uptake, were calculated from these measurements. The arterial IL-6 concentration was lower (   P < 0.05  ) after 120 min of exercise in GLU, but neither intramuscular glycogen nor IL-6 mRNA were different when comparing GLU with CON. However, net leg IL-6 release was attenuated (   P < 0.05  ) in GLU compared with CON. This corresponded with an enhanced (   P < 0.05  ) glucose uptake and a reduced (   P < 0.05  ) FFA uptake in GLU. These results demonstrate that glucose ingestion during exercise attenuates leg IL-6 release but does not decrease intramuscular expression of IL-6 mRNA.  相似文献   
40.
BACKGROUND: We report data on 1-year prevalence and comorbidity of depression, related impairment, treatment need, and psychiatric treatment among young adults. METHODS: A sample of young urban adults (n=245) mean age 21.8 years was screened from a baseline population of 706 high-school students and given a semistructured clinical interview to evaluate 12-month prevalence of depression, psychosocial functioning according to DSM-IV GAF scale, need for psychiatric treatment, and use of mental health services. RESULTS: One in 10 young adults suffered from depression with associated psychosocial impairment, the female-to-male-ratio being approximately 2:1. Most depressive disorders were comorbid with other DSM-IV disorders, depression usually occurring secondary to other disorders. Comorbidity was related to impairment, treatment need, and treatment contacts. Less than half of the depressed young adults had ever contacted mental health services, and less than one-third reported treatment contacts during the index episode. Males were less likely than females to report previous treatment contacts or intention to refer to mental health services for their problems, but treatment contacts during the index episode were reported equally often by both sexes. CONCLUSIONS: A minority of the severely depressed young adults with associated impairment had sought treatment. Except for subjects with dysthymia, no gender difference emerged in treatment contact rates during the 12-month depression episode. Comorbidity showed important clinical implications by its relation to severity of depression and treatment contacts.  相似文献   
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