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91.
A drinking water supply is a complicated system in its construction,operation,maintenance and need for public health surveillance.  相似文献   
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Existing evidence suggests an excess of winter births in schizophrenia and inconsistent results for other psychiatric conditions. The present study examined seasonal effects of birth among autistic individuals. Results revealed an excess of spring and carly summer births and an underrepresentation of winter and fall births. However, this pattern was obtained only for the male, nonverbal, and lower-functioning autistic subgroup.This project was supported in part by the Ontario Mental Health Foundation Grant #988-84/86.  相似文献   
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We show the systemic administration of low levels of TSH increases bone volume and improves bone microarchitecture and strength in aged OVX rats. TSH's actions are mediated by its inhibitory effects on RANKL-induced osteoclast formation and bone resorption coupled with stimulatory effects on osteoblast differentiation and bone formation, suggesting TSH directly affects bone remodeling in vivo. INTRODUCTION: Thyroid-stimulating hormone (TSH) receptor haploinsufficient mice with normal circulating thyroid hormone levels have reduced bone mass, suggesting that TSH directly affects bone remodeling. We examined whether systemic TSH administration restored bone volume in aged ovariectomized (OVX) rats and influenced osteoclast formation and osteoblast differentiation in vitro. MATERIALS AND METHODS: Sprague-Dawley rats were OVX at 6 months, and TSH therapy was started immediately after surgery (prevention mode; n = 80) or 7 mo later (restoration mode; n = 152). Hind limbs and lumbar spine BMD was measured at 2- or 4-wk intervals in vivo and ex vivo on termination at 8-16 wk. Long bones were subjected to microCT, histomorphometric, and biomechanical analyses. The direct effect of TSH was examined in osteoclast and osteoblast progenitor cultures and established rat osteosarcoma-derived osteoblastic cells. Data were analyzed by ANOVA Dunnett test. RESULTS: In the prevention mode, low doses (0.1 and 0.3 microg) of native rat TSH prevented the progressive bone loss, and importantly, did not increase serum triiodothyroxine (T3) and thyroxine (T4) levels in aged OVX rats. In restoration mode, animals receiving 0.1 and 0.3 microg TSH had increased BMD (10-11%), trabecular bone volume (100-130%), trabecular number (25-40%), trabecular thickness (45-60%), cortical thickness (5-16%), mineral apposition and bone formation rate (200-300%), and enhanced mechanical strength of the femur (51-60%) compared with control OVX rats. In vitro studies suggest that TSH's action is mediated by its inhibitory effects on RANKL-induced osteoclast formation, as shown in hematopoietic stem cells cultivated from TSH-treated OVX rats. TSH also stimulates osteoblast differentiation, as shown by effects on alkaline phosphatase activity, osteocalcin expression, and mineralization rate. CONCLUSIONS: These results show for the first time that systemically administered TSH prevents bone loss and restores bone mass in aged OVX rats through both antiresorptive and anabolic effects on bone remodeling.  相似文献   
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ABSTRACT:Background: In 1996 a new model of maternity care characterized by continuity of midwifery care from early pregnancy through the postpartum period was implemented for women attending Monash Medical Centre, a tertiary level obstetric service, in Melbourne, Australia. This study's purpose was to assess the impact of this model on women's views and experiences of care during the antenatal, intrapartum, and postpartum periods compared with views of women receiving standard maternity care. Methods: One thousand low‐ and high‐risk women who booked at the antenatal clinic and met the eligibility criteria were randomly allocated to continuity of midwifery care from a group of seven midwives in collaboration with medical staff, or to standard care from a variety of midwives and medical staff. Women's views of care were measured by means of a postal questionnaire at four months after the birth. Results: Team midwifery care was associated with increased satisfaction with antenatal, intrapartum, and some aspects of postpartum care. The differences were most obvious for antenatal care. Conclusions: Continuity of midwifery care is realistically achievable in a tertiary obstetric referral service and is associated with increased satisfaction. (BIRTH 30:1 March 2003)  相似文献   
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Repeated measures designs are often used to evaluate the effectiveness of interventions. In these designs, the outcomes are measured on several occasions before and after implementation of the intervention. Two statistical methods, the repeated measures analysis of variance (RM-ANOVA) and hierarchical linear models (HLM), can be used to analyze the data. The authors provide an overview of the statistical models underlying RM-ANOVA and HLM and discuss the strengths and limitations of each. They propose that the 2 methods are complementary in determining the effectiveness of interventions.  相似文献   
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Recent reports of sexually transmitted infection-rate increases among men indicate the need for renewed study of male sexual risk behavior to aid development of updated and novel risk reduction interventions. Men who have childhood sexual abuse (CSA) histories consistently report frequent sexual risk behavior. The objective of this sturdy is to explore whether posttraumatic stress disorder (PTSD) and depression are moderators and/or mediators of the association between CSA and sexual risk in adult men. A cross-sectional survey study employing random digit dial recruitment was administered to men aged 18–49 years from Philadelphia County. Two bundred ninety eight men were recruited and screened for CSA history, administered items from the Posttraumatic Stress Diagnostic Scale (PDS) and Center for Epidemiologic Studies—Depression (CES-D), and asked to estimate their number of lifetime sexual partners (LSPs). Effects of sociodemographic characteristics, CSA, PTSD, and depression on the number of LSPs were modeled using Poisson regression. Results show that 197 (66%) men participated; 43 (22%) had CSA histories. CSA was significantly associated with PTSD/depression (P=.03). Four sociodemographic variables (age, race, sexual identity, and education), CSA (incidence rate ratio, IRR=1.47, P<.001), PTSD (IRR=1.19, P=.04), depression (IRR=1.29, P=.001), all 2-way interactions, and the 3-way CSA/PTSD/depression interaction (IRR=11.00, P<.001) were associated with the number of LSPs (R2=0.27). In conclusion, sexual partnership patterns unique to men with CSA histories and comorbid PTSD/depression appear to lead to substantially higher numbers of LSPs. Estimates of this relationship may have been biased toward the null by underreporting that can occur with phone surveys. Cross-sectional studies do not support causal inferences; however, the identification of a moderating and mediating influence of PTSD/depression on the relationship between CSA and sexual risk behavior is important and suggests the need for future studies with larger samples that examine trajectories for CSA, psychiatric illness, and sexual partnerships.  相似文献   
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Background. Medication adherence impacts healthcare utilization. Pharmacy records are useful to establish fill patterns. Objective. Use pharmacy records to establish medication patterns fill patterns for comparison to healthcare utilization. Methods. Pharmacy records of 175 children with persistent asthma were collected and compared to healthcare utilization. Results. Majority of subjects had significant healthcare utilization, low numbers of rescue medications, and poor controller medication fill rates. Those with more rescue medications had more healthcare utilization and more controller medications. Conclusions. Pharmacy fill patterns demonstrate few rescue and/or controller medication fills. Those with more rescue medications reported increased healthcare utilization despite controller medications.  相似文献   
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