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101.
102.
Impaired strength adversely influences an older person’s ability to perform activities of daily living. A cross-sectional study of 117 independently living men and women (age = 73.4 ± 9.4 year; body mass index (BMI) = 27.6 ± 4.8 kg/m2) aimed to assess the association between body composition and: (1) upper body strength (handgrip strength, HGS); (2) lower extremity performance (timed up and go (TUG) and sit to stand test (STS)); and (3) endurance (6-minute walk (SMWT). Body composition (% fat; lean body mass (LBM)) was assessed using bioelectrical impedance. Habitual physical activity was measured using the Minnesota Leisure Time Physical Activity Questionnaire (MLTPA) and dietary macronutrient intake, assessed using 24 h recalls and 3-day food records. Regression analyses included the covariates, protein intake (g/kg), MLTPA, age and sex. For natural logarithm (Ln) of right HGS, LBM (p < 0.001) and % body fat (p < 0.005) were significant (r2 = 46.5%; p < 0.000). For left LnHGS, LBM (p < 0.000), age (p = 0.036), protein intake (p = 0.015) and LnMLTPA (p = 0.015) were significant (r2 = 0.535; p < 0.000). For SMW, % body fat, age and LnMLTPA were significant (r2 = 0.346; p < 0.000). For STS, % body fat and age were significant (r2 = 0.251; p < 0.000). LBM is a strong predictor of upper body strength while higher % body fat and lower physical activity are associated with poorer outcomes on tests of lower extremity performance.  相似文献   
103.
Dietary intakes of sodium and potassium are important determinants of blood pressure. We assessed sodium and potassium intake in a cross-sectional survey which included a random sample of New Zealand Adults aged 18 to 64 years from two New Zealand cities: Dunedin and Wellington. Participants completed a short questionnaire, had height, weight and blood pressure measured, and collected a 24 h urine sample. Mean 24 h sodium excretion was 3386 mg/day (95% CI 3221, 3551): 3865 mg/day for men and for 2934 mg/day women. Mean 24 h potassium excretion was 2738 mg/day (95% CI 2623, 2855): 3031 mg/day for men and 2436 mg/day for women. Mean sodium:potassium ratio was 1.32 (95% CI 1.26, 1.39); 1.39 for men and 1.26 for women. Sodium intake was higher among younger people, men, those with a higher BMI and higher potassium excretion. Potassium excretion was higher among older people, men and those with a higher sodium excretion. New Zealand adults have high sodium intakes and low potassium intakes compared to recommended levels. This is likely to adversely affect population blood pressure levels as well as incidence of cardiovascular disease. A comprehensive public health programme to reduce dietary sodium intake and increase intake of fruit and vegetables is warranted.  相似文献   
104.
105.
As part of a large study of the effects of HIV and AIDS on gay male sexual behaviour, we investigated the extent to which gay men in the UK have access to social support and informal care at times of illness. The study sample (n = 502) demonstrated high levels of willingness to disclose sexuality to others, sociability and social integration. Over 90% reported that they had access to people whom they could turn for practical help at times of temporary incapacity. Between 42% and 46% have known a person, or persons, with HIV symptomatic disease, AIDS or someone who has died of AIDS, although men recruited in larger towns and cities were more likely to know people at every stage of HIV infection and AIDS than those from smaller towns. Twenty-five per cent had provided practical help and support to at least one person with AIDS; men in this situation were more likely to have had a close friend, lover or former lover who had died of AIDS. It is argued that it is not possible to expect the gay community to provide fully for the non-medical care of its members and, whilst some needs can be fulfilled on an informal care basis, the demands of long-term serious illness are such that adequate support services should be available in the community.  相似文献   
106.
Summary: In 1505 patients with acute myocardial infarction (Ml) pericarditis was diagnosed most often in those with anterior transmural ECG changes. Those with pericarditis had a significantly greater hospital mortality and peak serum lactic dehydrogenase (LDH) levels and a greater incidence of left ventricular failure (LVF).
The patients reported here1 and our methods of study2, 4 have been described.  相似文献   
107.
We have shown an age-associated increase in plasma osmolality (p less than 0.001) in 152 randomly selected subjects, living in the community. In the old [mean age 78.0 (7.5) years] the plasma osmolality was 302.2 (300.6-303.8) mOsmol/kg compared with 291.2 (290.0-292.3) mOsmol/kg in the young [39.2 (11.2) years] (p less than 0.0001). In a further group of 20 screened, health status defined, elderly subjects the plasma osmolality was 298.1 (295.9-300.3) mOsmol/kg, which was significantly higher than the young group (p less than 0.0001) but lower than the unscreened old subjects (p = 0.005). The variance was also significantly lower (p = 0.03). The results may reflect a loosening of homoeostatic control and highlight the need for care in subject selection in studies of ageing.  相似文献   
108.
Background : The diagnosis of giant cell arteritis (GCA) is often confirmed by an early temporal artery (TA) biopsy of adequate length. Treatment of this condition with high‐dose corticosteroids may be associated with significant morbidity, including osteo­porosis. Aim: To audit current management of patients with suspected GCA at Auckland Healthcare, a large teaching hospital. Methods: We performed a retrospective chart review of all TA biopsies from January 1996 to June 2000. A total of 117 biopsies from 111 patients was audited. Of these patients, 37/111 (33%) had a final clinical diagnosis of GCA (GCA patients). The areas of interest for audit were waiting time for TA biopsy, length of sample, initial corticosteroid therapy and osteo­porosis prophylaxis. Results: The mean waiting time for biopsy for all patients was 5.6 days (range 0?42 days). This time varied from 9.3 days for rheumatology patients to 2.6 days for ophthalmology patients (P = 0.003). Only 44/117 (37.6%) specimens measured more than 10 mm. For GCA patients, the median initial oral prednisone dose was 60 mg/day. Osteoporosis prophylaxis was prescribed in 24/37 (65%) GCA patients, most commonly cyclical etidronate. Conclusions: There is significant variation in the management of GCA within our institution. This audit has highlighted several areas where improvement could be made, particularly in streamlining the process of obtaining TA biopsy and in promoting the use of osteoporosis prophylaxis. (Intern Med J 2002; 32: 315?319)  相似文献   
109.
Eighteen patients with neurobrucellosis are described. Eleven patients had meningitis alone or with papilledema, optic neuropathy, or radiculopathy. Four patients had meningovascular complications manifested by stroke or intracerebral hemorrhage from a presumed mycotic aneurysm. Two patients had parenchymatous dysfunction, including a child who had a cerebellar syndrome without evidence of direct infection of the central nervous system. One patient presented with polyradiculopathy. Twelve of 16 patients had pleocytosis; none had cell counts greater than 419 x 10(6)/L. Most patients had hypoglycorrhachia and elevated levels of protein in the cerebrospinal fluid (CSF). Results of an agglutination test for Brucella in serum were positive for all patients. Six of 16 patients had positive blood cultures, and four of 14 had positive CSF cultures. Antimicrobial treatment included concurrent administration of two or more of the following drugs: streptomycin, tetracycline (or doxycycline), rifampin, and trimethoprim-sulfamethoxazole. Eleven patients fully recovered. Five patients were left with residual neurological deficits. Four of these patients suffered permanent hearing loss, one of whom also had significant loss of vision in one eye. One elderly senile patient with meningovascular brucellosis remained in a vegetative state despite receiving antimicrobial therapy for 6 months. One patient died due to rupture of a mycotic aneurysm within 7 days of initiation of therapy. One other patient was treated after sustaining an intracerebral hemorrhage, but this patient's condition was diagnosed only after discharge.  相似文献   
110.
Protein kinase C catalyzed phosphorylation of sterol carrier protein 2   总被引:1,自引:0,他引:1  
The transport of cholesterol to the inner mitochondrial membrane, a key step in steroidogenesis, is subject to hormonal modulation that, at least in part, could be mediated by protein phosphorylation. This step is stimulated by sterol carrier protein 2 (SCP2) and Ca2+. To explore whether SCP2 itself is a potential control point for regulation by Ca2+-dependent phosphorylation we investigated whether highly purified SCP2 could serve as a substrate for major type Ca2+ and non-Ca2+-dependent protein kinases. Phosphorylation by calmodulin protein kinase II (CaM-PK II), myosin light chain kinase (MLCK), cAMP-dependent kinase (PKA) and protein kinase C (PKC) was monitored under optimal conditions for each enzyme. PKA, CaM-PK II and MLCK catalyzed the radiolabeling of histone 2A, synapsin I and myosin light chain (MLC), known substrates for these kinases, respectively, yet no phosphate transfer to SCP2 was observed. In contrast, PKC from two different sources (rat and calf brain) effectively catalyzed the phosphorylation of the highly purified SCP2. The phosphorylation of SCP2 depended on the addition of Ca2+ and phospholipids and was completely blocked by Polymyxin B, a PKC inhibitor. PKC catalyzed phosphorylation of SCP2 displayed a similar dependence on the concentration of ATP. Lineweaver Burk plots of the data indicate Km values for ATP of approximately 6 microM for the phosphorylation of SCP2. Our results, which have revealed for the first time that SCP2 is a substrate for PKC, are consistent with the possibilities that the control of steroidogenesis by tropic hormones and by PKC activation are mediated, at least in part, by the phosphorylation/dephosphorylation of SCP2.  相似文献   
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