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991.
A case-control study of maternal recreational physical activity and risk of gestational diabetes mellitus 总被引:9,自引:0,他引:9
Dempsey JC Butler CL Sorensen TK Lee IM Thompson ML Miller RS Frederick IO Williams MA 《Diabetes research and clinical practice》2004,66(2):203-215
Despite the maternal and infant morbidity associated with gestational diabetes mellitus (GDM), few modifiable risk factors have been identified. We explored the relation between recreational physical activity performed during the year before and during the first 20 weeks of pregnancy and the risk of GDM. 155 GDM cases and 386 normotensive, non-diabetic pregnant controls provided information about the type, intensity, frequency, and duration of physical activity performed during these time periods. Women who participated in any recreational physical activity during the first 20 weeks of pregnancy, as compared with inactive women, experienced a 48% reduction in risk of GDM (odds ratio [OR] = 0.52; 95% confidence interval [CI] 0.33-0.80). The number of hours spent performing recreational activities and the energy expended were related to a decrease in GDM risk. No clear patterns related to distance walked and pace of walking emerged. Daily stair climbing, when compared with no stair climbing, was associated with a 49-78% reduction in GDM risk (P for trend <0.011). Recreational physical activity performed during the year before the index pregnancy was also associated with statistically significant reductions in GDM risk, but women who engaged in physical activity during both time periods experienced the greatest reduction in risk (OR = 0.40; 95% CI 0.23-0.68). These data suggest that recreational physical activity performed before and/or during pregnancy is associated with a reduced risk of GDM. 相似文献
992.
Fluid shear stress generated by blood flowing over the endothelium is a major determinant of arterial tone, vascular remodeling, and atherogenesis. Nitric oxide (NO) produced by endothelial NO synthase (eNOS) plays an essential role in regulation of vascular function and structure by blood flow, but the molecular mechanisms that transduce mechanical force to eNOS activation are not well understood. In this study, we found that laminar flow (shear stress=12 dyne/cm2) rapidly activates vascular endothelial growth factor receptor 2 (VEGFR2) in a ligand-independent manner and leads to eNOS activation in cultured endothelial cells. Flow-stimulated VEGFR2 recruits phosphoinositide 3-kinase and mediates activation of Akt and eNOS. Inhibiting VEGFR2 kinase with selective inhibitors blocks flow-induced activation of Akt and eNOS and production of NO. Decreasing VEGFR2 expression with antisense VEGFR2 oligonucleotides significantly attenuates activation of Akt and eNOS. Furthermore, Src kinases are involved in flow-stimulated VEGFR2 because inhibiting Src kinases by PP2, a selective inhibitor for Src kinases, abolishes flow-induced VEGFR2 tyrosine phosphorylation and downstream signaling. Finally, we show that inhibiting VEGFR2 kinase significantly reduces flow-mediated NO-dependent arteriolar dilation in vivo. These data identify VEGFR2 as a key mechanotransducer that activates eNOS in response to blood flow. 相似文献
993.
Urinary tract infections (UTIs)--including cystitis, pyelonephritis, and catheter-associated infections--are among the most common nursing home-acquired infections. Asymptomatic bacteriuria can be identified in 20 to 50% of nursing home residents who do not have bladder catheters and in 100% of those who do. Diagnostic tests for nursing home patients with suspected UTI include urinalysis, urine culture, and sensitivity testing. Treatment of cystitis can usually be managed in the nursing home with oral antibiotics. Initial therapy with a parenteral agent is often recommended in nursing home-acquired pyelonephritis. 相似文献
994.
Monitoring and evaluation of programme to eliminate lymphatic filariasis (LF) depends on epidemiological assessment using appropriate indicators. Minimum efforts using reliable tests are necessary to guide the programme managers in decision-making. Impact of Mass Drug Administration (MDA) towards filariasis elimination can be assessed by the detection of microfilariae (mf) or parasite DNA (infective), filarial antigens (infected) and antibodies (exposure). It is also important to monitor drug resistance and variation in genetic structure of parasite populations using molecular markers. We developed a method to carry out parasitological, molecular, immunological and genetic analysis from a minimum volume of blood sample (about 150 μl) drawn from finger tip of an individual residing in LF endemic area. The method involves separation of sera for immunological assays and isolation of mf of Wuchereria bancrofti from the blood clots for counting, which were then used for W. bancrofti specific PCR, screening for albendazole sensitivity/resistance alleles by AS-PCR, RAPD profiling and ITS 2 PCR for genotyping. A protocol is also suggested for the separation of sera for assays to detect antigen and antibodies and isolation of mf from clots for genetic analysis. The protocol developed has shown potential application in monitoring several immunological, parasitological and molecular parameters from a limited amount of blood sample collected by finger prick, in large-scale operations. 相似文献
995.
The prognostic value of normal exercise myocardial perfusion imaging and exercise echocardiography: a meta-analysis. 总被引:2,自引:0,他引:2
Louise D Metz Mary Beattie Robert Hom Rita F Redberg Deborah Grady Kirsten E Fleischmann 《Journal of the American College of Cardiology》2007,49(2):227-237
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
996.
Arterburn DE McDonell MB Hedrick SC Diehr P Fihn SD 《The American journal of medicine》2004,117(10):738-746
PURPOSE: We hypothesized that obese adults with coronary heart disease, obstructive lung disease, or depression would report greater impairments in health-related quality of life owing to their angina, dyspnea, or depressive symptoms as compared with persons with normal body weight. METHODS: We analyzed cross-sectional data from the Ambulatory Care Quality Improvement Project, a multicenter study of veterans enrolled in general internal medicine clinics. Health-related quality of life was assessed using the Medical Outcomes Study Short Form-36, the Seattle Angina Questionnaire, the Seattle Obstructive Lung Disease Questionnaire, and the Hopkins Symptom Checklist for Depression. RESULTS: Compared with patients of normal weight (body mass index: 18.5 to 24.9 kg/m2), underweight patients (body mass index <18.5 kg/m2) reported health-related quality-of-life scores that were at least 5% lower (worse) in all 15 quality-of-life domains examined. Patients with class III obesity (body mass index > or =40 kg/m2) reported quality-of-life scores that were at least 5% lower than those of normal weight patients in eight domains. Scores of overweight patients (body mass index: 25 to 29.9 kg/m2) were higher (better) than those of normal weight patients in 11 domains. CONCLUSION: Body mass index was strongly associated with generic- and condition-specific health-related quality of life. Our results suggest that, when considering health-related quality-of-life outcomes among veterans, the optimal body mass index may be above the "normal" range. Further research should test the validity of the 1998 National Institutes of Health body mass index categories as predictors of health outcomes among veterans. 相似文献
997.
Olson N O'Meara ES Jenny NS Folsom AR Bovill EG Furberg CD Heckbert SR Psaty BM Cushman M 《American journal of hematology》2008,83(7):524-527
Lipoprotein-associated phospholipase A2 (Lp-PLA2) is an enzyme involved in inflammation and platelet function. Inherited deficiency and elevated levels are associated with atherosclerosis. Given potential common etiologies of atherosclerosis and venous thrombosis (VT), we hypothesized that low and high Lp-PLA2 would be associated with VT risk. Lp-PLA(2) mass and activity were measured in baseline samples of Cardiovascular Health Study participants (5,888 men and women age > or =65), excluding 354 reporting pre-baseline VT. The study endpoint was VT unrelated to cancer after 11.6 years follow-up. Hazard ratios were estimated using Cox proportional hazard models, adjusting for age, race, sex, and body-mass index. With 129 cases of VT, there was no association of Lp-PLA2 activity with risk. Adjusted hazard ratios were 1.19 (CI 0.62, 2.29) and 0.87 (CI 0.43, 1.76) for the lowest and highest decile, respectively, compared to the 10-25th percentile. Corresponding hazard ratios for Lp-PLA2 mass were 1.63 (CI 0.79, 3.34) and 1.33 (CI 0.61, 2.87). Results were robust to several definitions of low or high Lp-PLA2. While the association of Lp-PLA(2) levels with arterial disease events implies a role for this enzyme in atherogenesis, our findings suggest that it is not prothrombotic. 相似文献
998.
Terence R. J. Lappin G. Elizabeth Elder Timothy Taylor Mary Frances McMullin John M. Bridges 《British journal of haematology》1988,70(1):117-120
The mouse spleen cell assay (MSCA) has been compared with a radioimmunoassay for the measurement of serum erythropoietin (Ep). In 20 normal subjects the serum values ranged from 15 to 73 mU/ml for the MSCA compared with 5-30 mU/ml for the RIA. For normal sera there was no correlation between the results of the two assays. In 37 patients with anaemias of differing aetiologies and at various stages of treatment values ranged from 10 to 3645 mU/ml for the MSCA and 13-10,000 mU/ml for the RIA. Although patient values from the two assays were highly correlated (r = 0.98, P less than 0.001), the MSCA results were generally lower. These discrepancies can be largely accounted for by two factors. Firstly the MSCA is sensitive to non-specific matrix effects. Secondly, heat inactivation of serum, a prerequisite for the MSCA, but not for the RIA, destroys a variable and unpredictable proportion of the Ep in the test sera leading to an underestimation of Ep in the MSCA. We conclude that the RIA is more reliable than the MSCA which, in its present form, cannot be recommended for the accurate measurement of serum erythropoietin. 相似文献
999.
Ballard W. Perry Gold Jeffrey P. Charlson Mary E. 《Journal of general internal medicine》1986,1(4):220-224
Compliance with the consultant’s recommendations is one measure of the effectiveness of a consultation. A previous study showed
that compliance was better when fewer recommendations were made. In the subsequent year, consultants were encouraged to limit
their recommendations to five or fewer. Despite a significant decrease in the number of recommendations, compliance rates
remained essentially unchanged (72%). Multivariate analysis demonstrated that the clinical severity of the patient’s disease
and the number of associated problems, as well as the types of recommendations, were significant predictors of compliance.
Compliance was best for recommendations involving medications (84%) and worst for recommendations involving diagnostic tests
(62%). Compliance was also evaluated in the context of a surgeon’s view of the appropriateness of the recommendations. For
recommendations felt to be essential to patient care the compliance rate was 75%, but it was only 44% for recommendations
judged non-essential (p<0.001). The consulting internist should be aware that the surgeon’s view of the relevance of the recommendations
to patient care needs may have an important effect on compliance.
Received from the Departments of Medicine and Surgery, Cornell University Medical College, New York, New York. Dr. Ballard
was a Henry J. Kaiser Foundation Fellow in General Internal Medicine. Dr. Gold is a Fellow in Cardio-Thoracic Surgery, Brigham
and Women’s Hospital, Harvard Medical School, Boston, Massachusetts. Dr. Charlson is a Henry J. Kaiser Family Foundation Faculty
Scholar in General Internal Medicine. 相似文献
1000.
Burton I. Korelitz MD 《Digestive diseases and sciences》1985,30(5):506-506