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961.
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The Institute of Medicine has recommended that policy decisions about improvement of national public health systems be guided by sound scientific evidence. However, to date there is no national research agenda to help guide public health systems. The Centers for Disease Control and Prevention was called upon to lead a collaborative consensus-based process to define key research questions and establish a framework to create opportunities to better coordinate, leverage, and identify public health resources, which are increasingly scarce. The public health systems research agenda that emerged from this process has 14 over-arching priority research themes. This national agenda should stimulate and guide research to meet the urgent need to improve the nation's public health systems.  相似文献   
963.
BACKGROUND: Perchlorate is commonly found in the environment and known to inhibit thyroid function at high doses. Assessing the potential effect of low-level exposure to perchlorate on thyroid function is an area of ongoing research. OBJECTIVES: We evaluated the potential relationship between urinary levels of perchlorate and serum levels of thyroid stimulating hormone (TSH) and total thyroxine (T4) in 2,299 men and women, > or = 12 years of age, participating in the National Health and Nutrition Examination Survey (NHANES) during 2001-2002. METHODS: We used multiple regression models of T4 and TSH that included perchlorate and covariates known to be or likely to be associated with T4 or TSH levels: age, race/ethnicity, body mass index, estrogen use, menopausal status, pregnancy status, premenarche status, serum C-reactive protein, serum albumin, serum cotinine, hours of fasting, urinary thiocyanate, urinary nitrate, and selected medication groups. RESULTS: Perchlorate was not a significant predictor of T4 or TSH levels in men. For women overall, perchlorate was a significant predictor of both T4 and TSH. For women with urinary iodine < 100 microg/L, perchlorate was a significant negative predictor of T4 (p < 0.0001) and a positive predictor of TSH (p = 0.001). For women with urinary iodine > or = 100 microg/L, perchlorate was a significant positive predictor of TSH (p = 0.025) but not T4 (p = 0.550). CONCLUSIONS: These associations of perchlorate with T4 and TSH are coherent in direction and independent of other variables known to affect thyroid function, but are present at perchlorate exposure levels that were unanticipated based on previous studies.  相似文献   
964.
The silatecan 7-tert-butyldimethylsilyl-10-hydroxy-camptothecin (DB-67) represents a new generation of camptothecin derivatives that exhibits a potent in vitro DNA topoisomerase I (TOP1)-mediated DNA-damaging activity, improved blood stability, and holds significant promise for the treatment of human cancers. In this study, we characterize the role of TOP1 in mediating the radiosensitization activity of DB-67. As examined by clonogenic survival assay, DB-67 exhibited potent radiosensitization activity at a concentration 10-fold lower than camptothecin in the human glioma D54-MG and T-98G cells, which harbor wild-type and mutant p53, respectively. Analyzed by the single-hit multitarget model, DB-67 induced radiosensitization by obliterating the "shoulder" of the radiation survival curve in the D54-MG cells. The in vivo targeting of TOP1 by DB-67 was investigated by immunoblot analysis. In a dose-dependent manner, DB-67 specifically stimulates covalent linking of TOP1 to chromosomal DNA at concentrations 10-fold lower than camptothecin in the D54-MG cells. The potency of in vivo targeting of TOP1 by DB-67 correlates well with its cytotoxicity and radiosensitization activity. Furthermore, DB-67 exhibited substantially less cytotoxicity and radiosensitization activity in the TOP1 mutant Chinese hamster lung fibroblast DC3F/C-10 cells than in their parental DC3F cells. Together, our data show that DB-67 exhibits potent cytotoxicity and radiosensitization activity by targeting TOP1 in mammalian cells and has great potential for being developed to treat human cancers.  相似文献   
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Purpose

Riata and Riata ST defibrillator leads (St. Jude Medical, Sylmar, CA, USA) have been recalled due to increased risk of insulation failure leading to externalized cables. As this mechanical failure does not necessarily correlate with electrical failure, it can be difficult to diagnose. Fluoroscopic screening can identify insulation failure. Studies have suggested that insulation failure is predominantly seen in 8-Fr, single-coil models. Our patients have exclusively dual-coil leads and a high proportion of 7-Fr leads.

Methods

Fluoroscopic screening was performed in 48 patients with recalled Riata leads. Twenty-three patients had 8-Fr Riata leads and 25 patients had 7-Fr Riata ST leads. Images were recorded in at least three projections and studies were reviewed by seven attending electrophysiologists.

Results

Externalized cables were seen in ten patients (21 %), and another five patients (10 %) had abnormal cable spacing. All device interrogations showed normal parameters. Patients with abnormal leads had more leads in situ (2.5?±?0.7 vs. 1.6?±?0.8 leads; P?=?0.002) and a higher rate of nonischemic cardiomyopathy (80 vs. 24 %; P?=?0.03). There were no differences between the groups with regards to patient age, body mass index, lead age, lead parameters, or vascular access site. There was no difference with regard to lead size (P?=?0.76).

Conclusions

The Riata family of leads has a high incidence of mechanical failure, as demonstrated on fluoroscopic screening. In this study, the 7-Fr models were just as likely to mechanically fail as the 8-Fr models. Increasing lead burden and a diagnosis of nonischemic cardiomyopathy correlated with insulation failure.  相似文献   
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ABSTRACT

In China, men who have sex with men (MSM) are the fastest growing population at risk for HIV. They face social stigma due to both MSM behavior and HIV. In addition, concern has been raised about the mental health of wives of MSM. In this cross-sectional study, the authors examine the mental health status of a sample of 135 of these women. Participants completed an Internet-administered questionnaire in Xi’an from April to June, 2012. Most were unaware at the time of marriage that their husbands were MSM. Physical abuse was frequently reported; depressive symptom and mental health (Symptom Checklist, SCL–90) scores were significantly higher than those of the general Chinese adult female population. A majority (59.8%) of women reported suicidal thoughts after discovering their husbands’ MSM behavior; about 10% had attempted suicide. Multiple logistic regression revealed that women’s experience with anal sex was associated with 7.8 times (95% CI: 1.3–65.9) greater odds of suicidal ideation. Also, women who demonstrated mental symptoms on the SCL–90 had 2.3 times (95% CI: 1.04–5.2) the odds of suicidal ideation. These results suggest that wives of MSM have a significant need for mental health care, suicide prevention, HIV education, and social support.  相似文献   
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