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91.
Severe constant and intermittent knee pain are associated with “unacceptable” symptoms in older adults with osteoarthritis (OA) [22]. We hypothesized that constant and intermittent pain would be independently related to physical function, with intermittent knee pain being a better predictor of future declines in physical function in early symptomatic knee OA. This study included men (n?=?189) and women (n?=?133) with radiographic, unilateral knee OA, observed using data from the Osteoarthritis Initiative (OAI). Pain types were measured using the Intermittent and Constant Osteoarthritis Pain (ICOAP) scale. Physical function was measured using the Western Ontario and McMaster Universities Arthritis Index (WOMAC-PF) and Knee Injury and Osteoarthritis Outcome Score (KOOS-FSR) and physical performance tests. High baseline intermittent (B?=?0.277; p?=?0.001) and constant (B?=?0.252; p?=?0.001) knee pain were related to poor WOMAC-PF. Increased constant (B?=?0.484; p?=?0.001) and intermittent (B?=?0.104; p?=?0.040) pain were related to 2-year decreased WOMAC-PF. High baseline intermittent knee pain predicted poor KOOS-FSR at year 2 (B?=??0.357; p?=?0.016). Increased constant pain was related to decreased chair stand test performance over 2 years in women (B?=?0.077; p?=?0.001). High baseline intermittent pain was related to poor performance on repeated chair stands (B?=?0.035; p?=?0.021), while baseline constant pain was related to poor 400-m walk performance in women (B?=?0.636; p?=?0.047). Intermittent and constant knee pain were independent factors in self-perceived physical function and were important predictors of future limitations in physical function. Identifying intermittent and constant pain in early symptomatic OA may allow patients to adopt strategies to prevent worsening pain and future declines in physical function.  相似文献   
92.
OBJECTIVES: The purpose of this work was to determine the prognostic value of normal exercise myocardial perfusion imaging (MPI) tests and exercise echocardiography tests, and to determine the prognostic value of these imaging modalities in women and men. BACKGROUND: Exercise MPI and exercise echocardiography provide prognostic information that is useful in the risk stratification of patients with suspected coronary artery disease (CAD). METHODS: We searched the PubMed, Cochrane, and DARE databases between January 1990 and May 2005, and reviewed bibliographies of articles obtained. We included prospective cohort studies of subjects who underwent exercise MPI or exercise echocardiography for known or suspected CAD, and provided data on primary outcomes of myocardial infarction (MI) and cardiac death with at least 3 months of follow-up. Secondary outcomes (unstable angina, revascularization procedures) were abstracted if provided. Studies performed exclusively in patients with CAD were excluded. RESULTS: The negative predictive value (NPV) for MI and cardiac death was 98.8% (95% confidence interval [CI] 98.5 to 99.0) over 36 months of follow-up for MPI, and 98.4% (95% CI 97.9 to 98.9) over 33 months for echocardiography. The corresponding annualized event rates were 0.45% per year for MPI and 0.54% per year for echocardiography. In subgroup analyses, annualized event rates were <1% for each MPI isotope, and were similar for women and men. For secondary events, MPI and echocardiography had annualized event rates of 1.25% and 0.95%, respectively. CONCLUSIONS: Both exercise MPI and exercise echocardiography have high NPVs for primary and secondary cardiac events. The prognostic utility of both modalities is similar for both men and women.  相似文献   
93.
CD34+ progenitor cells can harbour latent human cytomegalovirus (HCMV); however, the mechanisms of HCMV latency remain unclear. We have investigated the effects of the haematopoietic lineage restriction on the establishment and spread of the latent HCMV to progeny cells. In vitro-infected and latently-infected haematopoietic progenitor cells derived from HCMV seropositive donors were studied. The presence of HCMV DNA in bone marrow progenitor (BMP) cells was determined by single colony polymerase chain reaction and fluorescent in situ hybridization (FISH). The presence of CMV DNA was found to be restricted to myeloid progenitors and the percentage of HCMV-infected cells was lower in naturally-infected cells than in in vitro-infected cells. Erythroid differentiation resulted in an abortive infection with persistence of the viral nucleic acids in red cell precursors. In BMP cells from HCMV seronegative donors, HCMV DNA was localized in the nucleus. Bone marrow progenitors in the presence of granulocyte-macrophage colony stimulating factor (GMCSF) maintained HCMV DNA for extended periods of time. No viral production could be detected throughout the culture but the comparison of the numbers of latently-infected cells prior to and after the culture suggests that proliferation of haematopoietic progenitor cells may lead to the expansion of latently-infected cells.  相似文献   
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BACKGROUND: Sit-to-stand (STS) performance is often used as a measure of lower-limb strength in older people and those with significant weakness. However, the findings of recent studies suggest that performance in this test is also influenced by factors associated with balance and mobility. We conducted a study to determine whether sensorimotor, balance, and psychological factors in addition to lower-limb strength predict sit-to-stand performance in older people. METHODS: Six hundred and sixty nine community-dwelling men and women aged 75-93 years (mean age 78.9, SD = 4.1) underwent quantitative tests of strength, vision, peripheral sensation, reaction time, balance, health status, and sit-to-stand performance. RESULTS: Many physiological and psychological factors were significantly associated with sit-to-stand times in univariate analyses. Multiple regression analysis revealed that visual contrast sensitivity, lower limb proprioception, peripheral tactile sensitivity, reaction time involving a foot-press response, sway with eyes open on a foam rubber mat, body weight, and scores on the Short-Form 12 Health Status Questionnaire pain, anxiety, and vitality scales in addition to knee extension, knee flexion, and ankle dorsiflexion strength were significant and independent predictors of STS performance. Of these measures, quadriceps strength had the highest beta weight, indicating it was the most important variable in explaining the variance in STS times. However, the remaining measures accounted for more than half the explained variance in STS times. The final regression model explained 34.9% of the variance in STS times (multiple R =.59). CONCLUSIONS: The findings indicate that, in community-dwelling older people, STS performance is influenced by multiple physiological and psychological processes and represents a particular transfer skill, rather than a proxy measure of lower limb strength.  相似文献   
98.
Validation of a brief screening test for depression in the elderly   总被引:2,自引:0,他引:2  
This paper describes the clinical validation of the 10-question Short Zung Interviewer-assisted Depression Rating Scale (Short Zung I.D.S.) which has been derived from the 20-question Zung Self-rating Depression Scale (Zung S.D.S) for use in the elderly. The Short Zung I.D.S. was administered to 104 elderly volunteers from the community and to 33 elderly depressed patients assessed by a psychiatrist. The mean scores (41.3 and 81.0, respectively) were significantly different (P less than 0.0001). The Short Zung I.D.S. has proved to be a useful brief screening test for depression in the elderly and should be of value in measuring changes in mood.  相似文献   
99.
The US Air Force Academy experienced a point-source outbreak of gastroenteritis originally believed to be caused by Salmonella. The overall attack rate was 48% among approximately 3000 cadets and staff. Food-specific attack rates implicated chicken salad. The odds ratio for chicken salad consumption in ill cadets was 10.7 (95% confidence interval: 8.2; 13.8). The celery component had been exposed to nonpotable water. Citrobacter freundii were statistically associated with consumption of the suspected vehicle and subsequent illness. Most aspects were consistent with the epidemiology of Norwalk gastroenteritis. However, the clinical presentation was not typical of reported outbreaks. One hundred five cadets required intravenous rehydration. Serum samples implicated Norwalk virus as the most probable cause of this outbreak. The Centers for Disease Control (Atlanta, Ga) recently began national surveillance for viral gastroenteritis. All outbreaks of gastroenteritis associated with nonpotable water should be investigated for evidence of viral cause.  相似文献   
100.
Vitamin D deficiency is prevalent in the pediatric CKD population. Recognizing that renal transplant recipients have CKD, we assessed the prevalence of vitamin D insufficiency and deficiency in pediatric renal transplant recipients, compared to a healthy pediatric population. We prospectively studied 25(OH)D levels in 29 pediatric renal transplant recipients and 45 control patients over one yr. The overall prevalence of vitamin D insufficiency and deficiency was common in both populations, at 76% (95% CI: 61, 87%) in the pediatric renal transplant recipients and 91% (95% CI: 80, 98%) in the control group. In the paired renal transplant samples, the mean 25(OH)D level was 52.3 ± 17.9 nmol/L in the winter and 65.6 ± 18.8 nmol/L in the summer (95% CI diff.: 3.9, 22.7), in keeping with a significant seasonal difference. The mean dietary intake of vitamin D in the renal transplant recipients, assessed by three‐day dietary record, was 5.7 μg/day, with a vitamin D intake below the EAR in the majority. We did not find an association between vitamin D intake and 25(OH)D levels in this study, likely due to the low dietary intake of vitamin D within the transplant population, identifying a potential area for intervention and improvement.  相似文献   
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