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排序方式: 共有558条查询结果,搜索用时 15 毫秒
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R Villegas XO Shu G Yang CE Matthews H Li H Cai Y Gao W Zheng 《Nutr Metab Cardiovasc Dis》2009,19(3):190-197
BACKGROUND AND AIMS: The combined effect of the components of energy balance (energy intake and physical activity) and the development of type 2 diabetes (T2D) has not been adequately investigated. The aim of this study was to examine the components of energy balance and the incidence of T2D in a cohort of middle-aged women. METHODS AND RESULTS: A population-based prospective study of 64,227 middle-aged Chinese women who had no prior history of diabetes or chronic disease at study recruitment. Participants completed in-person interviews at baseline and follow-up surveys that collected information on diabetes risk factors including dietary and physical activity habits and disease occurrence. Anthropometric measurements were taken by trained interviewers at recruitment. Average follow-up time was 4.6 years. During 297,755 person-years of follow-up, 1608 new cases of T2D were documented. Body mass index (BMI) and weight gain (since age 20) were strongly associated with T2D incidence. Energy intake (EI) was associated with modestly increased risk, while physical activity (PA) was associated with decreased risk of T2D. Less active women with higher EI had higher risk of T2D (RR=1.96; 95% CI: 1.44, 2.67) than active women with lower EI (P(interaction)=0.02). The EI to PA (EI:PA) ratio was positively associated with T2D risk; the association was more evident among overweight and obese women (BMI > or = 23 kg/m(2)). CONCLUSION: These data suggest that energy balance plays an important role in the development of T2D, and this effect may be modified by BMI. 相似文献
85.
Intravascular tumors: transvenous biopsy 总被引:1,自引:0,他引:1
A technique is described for transfemoral biopsy of intravenous tumors. Positive results were obtained at biopsy in three patients who had an intraluminal mass in the inferior vena cava and in one patient with a mass in the iliac vein. Transvenous biopsy is helpful in obtaining a histologic diagnosis and provides an alternative method to surgery or percutaneous transabdominal needle biopsy. 相似文献
86.
A healthy girl of 10 years presented with lumps on her tongue, shown on biopsy to be neuromas. She had had operations to her feet for pes cavus and was relatively long-limbed but had no other 'Marfanoid' features. She had a high plasma calcitonin level. At operation a normal sized thyroid gland was totally removed. It contained two discrete masses of malignant C-cells and diffuse foci elsewhere. The plasma calcitonin fell slowly to normal on follow-up but was noted to be rising 2 1/2 years later. We stress the importance of making this diagnosis as early as possible and mention briefly another child aged 15 months, similarly diagnosed and operated upon. 相似文献
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SNAP-25 deficit and hippocampal connectivity in schizophrenia 总被引:3,自引:2,他引:1
Young CE; Arima K; Xie J; Hu L; Beach TG; Falkai P; Honer WG 《Cerebral cortex (New York, N.Y. : 1991)》1998,8(3):261-268
Regional abnormalities of brain connectivity may be an important substrate
for the expression of schizophrenia, a severe form of mental illness. Brain
imaging and postmortem morphometric studies indicate hippocampal structure
is abnormal in schizophrenia. To study molecular components of hippocampal
connectivity the presynaptic proteins SNAP-25 and synaptophysin were
assayed in postmortem samples. Immunocytochemical studies indicated reduced
SNAP-25 immunoreactivity in schizophrenia compared to controls,
particularly in the terminal fields of entorhinal cortex projections.
Although there were no overall changes in synaptophysin immunoreactivity,
in the granule cell layer of the dentate gyrus synaptophysin
immunoreactivity was increased in schizophrenia. These results indicate
that disconnection of a subset of hippocampal circuitry from the entorhinal
cortex, as well as intrinsic changes in hippocampal connectivity, may
contribute to the mechanism of illness in schizophrenia.
相似文献
90.
MP Busch ; EA Operskalski ; JW Mosley ; CE Stevens ; ER Schiff ; SH Kleinman ; H Lee ; M Lee ; M Harris 《Transfusion》1994,34(10):858-864
BACKGROUND: The long-term course of human immunodeficiency virus type 1 (HIV-1)-related disease among seropositive blood donors has not been described. The enrollment and epidemiologic background of HIV-1- infected donors in the Transfusion Safety Study and their immunologic and clinical progression are described. STUDY DESIGN AND METHODS: Through the testing of approximately 200,000 sera from donations made in late 1984 and early 1985, 146 anti-HIV-1-positive donors and 151 uninfected matched donors were enrolled. These two cohorts were followed with 6-month interval histories and laboratory testing. RESULTS: Seropositive donors detected before the institution of routine anti-HIV-1 screening disproportionately were first-time donors and men with exclusively male sexual contacts. The actuarial probability of a person's developing AIDS within 7 years after donation was 40 percent; the probability of a person's dying of AIDS was 28 percent. AIDS developed more often when the donor was p24 antigen-positive at donation. Over a 3-year period, significant decreases occurred in CD4+, CD2+CD26+, CD4+CD29+, and CD20+CD21+ counts, but not in CD8+ subsets, CD20+, or CD14+. CONCLUSION: The high proportions of first-time donations and exclusively homosexual men among seropositive donors suggest that test-seeking may have contributed to the high HIV-1 prevalence in the repository. Implementation of alternative test sites when routine donor screening began in 1985 may have averted many high- risk donations. The disease course in HIV-1-infected donors had the same wide spectrum of immunologic and clinical manifestations as were reported for other cohorts. 相似文献