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991.
992.
Gold CH Malmberg B McClearn GE Pedersen NL Berg S 《The journals of gerontology. Series B, Psychological sciences and social sciences》2002,57(3):S168-S176
OBJECTIVES: The primary goal of this study was to assess gender differences in various measures of health conditions, symptoms, and self-rated health among older persons by comparing brothers and sisters in a sample of unlike-sex twins. METHODS: All living pairs of unlike-sex twins born between 1906 and 1925 were identified through the Swedish Twin Registry and sent surveys assessing health and other factors. This population-based sample consisted of 605 twin pairs. Paired sample t tests were used to analyze gender differences in health-related measures, including a three-level measure of health problems based on physicians' ratings. RESULTS: Women had more total health conditions, not life-threatening health conditions, somewhat life-threatening cardiovascular conditions, and physical and psychological symptoms. Men had more very life-threatening health conditions and cardiovascular conditions. No gender differences were found in somewhat life-threatening health conditions, total cardiovascular conditions, or self-rated health. DISCUSSION: Important gender differences and similarities in health were found using an unlike-sex twin design that reduced variability due to background characteristics. This design also minimized problems caused by gender differences in survival. Research on gender and health in older persons requires more detailed approaches to address the complexity of this topic. 相似文献
993.
Lymphadenopathy-associated virus antibodies and T cells in hemophiliacs treated with cryoprecipitate or concentrate 总被引:1,自引:0,他引:1
Gjerset GF; McGrady G; Counts RB; Martin PJ; Jason J; Kennedy S; Evatt B; Hansen JA 《Blood》1985,66(3):718-720
Evidence for exposure to lymphadenopathy-associated virus (LAV) was investigated in 48 patients with hemophilia, 15 of whom had been treated exclusively with single-donor cryoprecipitate. The prevalence of antibodies to LAV in all patients was 53% in 1983 and 63% in 1984, while in patients treated only with cryoprecipitate, the prevalence was 31% in 1983 and 40% in 1984. Patients treated with any concentrate had a seroprevalence of 65% in 1983 and 77% in 1984. Seropositive patients were more likely to have a significant reduction in the ratio of helper to suppressor T cells, absolute numbers of helper T cells, and T cell function in vitro. Seven of 18 patients who were seronegative in 1983 had seroconverted by 1984. The relative risk of seroconversion for patients using any concentrate since 1981 compared with those using cryoprecipitate only was 3.9 (P = .04). Nevertheless, the rate of conversion in the latter group was 18% per year. 相似文献
994.
The biochemical and clinical consequences of 2'-deoxycoformycin in refractory lymphoproliferative malignancy 总被引:4,自引:1,他引:4
Grever MR; Siaw MF; Jacob WF; Neidhart JA; Miser JS; Coleman MS; Hutton JJ; Balcerzak SP 《Blood》1981,57(3):406-417
A deficiency of adenosine deaminase, an enzyme important in purine nucleoside catabolism, is associated with a severe combined immunodeficiency disease in children. Inhibition of this enzyme in vitro and in vivo results in an impairment in lymphoblast proliferation. We have investigated the pharmacologic inhibition of this enzyme by 2'-deoxycoformycin in 15 patients with hematologic malignancies. Biochemical consequences of the administration of this agent were closely monitored in erythrocytes, nucleated peripheral blood and bone marrow cells, serum, and urine. A marked rise in erythrocyte dATP was accompanied by a depletion of ATP in those patients exhibiting toxicity. Most patients excreted large amounts of deoxyadenosine but not adenosine in the urine. Serum deoxyadenosine rose in patients demonstrating a marked decrease in cell mass. The biochemical disturbances and clinical toxicity, including hepatic, renal, and conjunctival abnormalities, were usually reversible. Central nervous system toxicity, which potentially was the most serious consequence, was associated with high erythrocyte dATP/ATP ratios and high levels of cerebrospinal fluid deoxyadenosine. In patients with lymphoma and leukemia, objective responses were observed but were short- lived. Patients with chronic lymphocytic leukemia receiving weekly low doses of the drug demonstrated minimal toxicity and some efficacy. The chemotherapeutic potential o 2'-deoxycoformycin, as either a single agent or in combination with Ara-A, merits further exploration. 相似文献
995.
THE ENZYMATIC METHYLATION OF RNA AND DNA, VIII. EFFECTS OF BACTERIOPHAGE INFECTION ON THE ACTIVITY OF THE METHYLATING ENZYMES 总被引:1,自引:0,他引:1
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996.
John Heintzman Steffani R Bailey Megan J Hoopes Thuy Le Rachel Gold Jean P O'Malley Stuart Cowburn Miguel Marino Alex Krist Jennifer E DeVoe 《J Am Med Inform Assoc》2014,21(4):720-724
To compare the agreement of electronic health record (EHR) data versus Medicaid claims data in documenting adult preventive care. Insurance claims are commonly used to measure care quality. EHR data could serve this purpose, but little information exists about how this source compares in service documentation. For 13 101 Medicaid-insured adult patients attending 43 Oregon community health centers, we compared documentation of 11 preventive services, based on EHR versus Medicaid claims data. Documentation was comparable for most services. Agreement was highest for influenza vaccination (κ = 0.77; 95% CI 0.75 to 0.79), cholesterol screening (κ = 0.80; 95% CI 0.79 to 0.81), and cervical cancer screening (κ = 0.71; 95% CI 0.70 to 0.73), and lowest on services commonly referred out of primary care clinics and those that usually do not generate claims. EHRs show promise for use in quality reporting. Strategies to maximize data capture in EHRs are needed to optimize the use of EHR data for service documentation. 相似文献
997.
Draper CE Quon A Fredericson M Besier TF Delp SL Beaupre GS Gold GE 《Journal of magnetic resonance imaging : JMRI》2012,36(4):928-932
Purpose:
To determine whether bone metabolic activity corresponds to bone and cartilage damage in patients with patellofemoral pain.Materials and Methods:
We acquired magnetic resonance imaging (MRI) and 18F‐NaF positron emission tomography (PET) / computed tomography (CT) scans of the knees of 22 subjects. We compared locations of increased tracer uptake on the 18F‐NaF PET images to bone marrow edema and cartilage damage visualized on MRI.Results:
We found that increased bone activity on 18F‐NaF PET does not always correspond to structural damage in the bone or cartilage as seen on MRI.Conclusion:
Our results suggest that 18F‐NaF PET/CT may provide additional information in patellofemoral pain patients compared to MRI. J. Magn. Reson. Imaging 2012;36:928–932. © 2012 Wiley Periodicals, Inc. 相似文献998.
999.
Both caloric restriction and overeating have been shown to affect neural processes associated with reinforcement. Both preclinical and some clinical studies have provided evidence that food restriction may increase reward sensitivity, and while there are mixed findings regarding the effects of overeating on reward sensitivity, there is strong evidence linking this behavior with changes in reward-related brain regions. Evidence of these changes comes in part from findings that show that such eating patterns are associated with increased drug use. The data discussed here regarding the differential effects of various eating patterns on reward systems may be particularly relevant to the aging population, as this population has been shown to exhibit altered reward sensitivity and decreased caloric consumption. Moreover, members of this population appear to be increasingly affected by the current obesity epidemic. Food, like alcohol or drugs, can stimulate its own consumption and produce similar neurochemical changes in the brain. Age-related loss of appetite, decreased eating, and caloric restriction are hypothesized to be associated with changes in the prevalence of substance misuse, abuse, and dependence seen in this cohort. 相似文献
1000.