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OBJECTIVE: To estimate the prevalence of hyperemesis gravidarum (HG) in women living in Norway by their country of birth, and explore whether the variations in the occurrence of HG could be explained by the differences in maternal sociodemographic factors. DESIGN: This was a cross-sectional study. METHODS: All primiparous women registered in the Medical Birth Registry of Norway (MBRN) from 1967 through June 2005 (N=900,074) comprised the sample. Data on HG, age, plurality and sex of the fetus were obtained from the MBRN and linked to the data on country of birth and maternal education obtained from Statistics Norway. Independent associations between country of birth and HG were studied by multiple logistic regression with and without adjustment for potential confounders. RESULTS: The overall prevalence of HG in primiparous women in Norway during the study period was 0.89% (95% confidence interval (CI) 0.88-0.92). Women born in Western Europe had the lowest prevalence of HG (0.8%), whereas those born in India and Sri Lanka had the highest (3.2%). Women born in Africa (except North Africa) and India or Sri Lanka were 3.4 (95% CI 2.7- 3.5) and 3.3 (95% CI 2.6-3.4) times more likely to develop HG than women born in Norway, after adjustment for potential confounders. CONCLUSIONS: Substantial variations in the prevalence of HG in Norway by country of birth cannot be explained by the differences in maternal sociodemographic factors.  相似文献   
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OBJECTIVES: To examine the association between strength, function, lean mass, muscle density, and risk of hospitalization.
DESIGN: Prospective cohort study.
SETTING: Two U.S. clinical centers.
PARTICIPANTS: Adults aged 70 to 80 (N=3,011) from the Health, Aging and Body Composition Study.
MEASUREMENTS: Measurements were of grip strength, knee extension strength, lean mass, walking speed, and chair stand pace. Thigh computed tomography scans assessed muscle area and density (a proxy for muscle fat infiltration). Hospitalizations were confirmed by local review of medical records. Negative binomial regression models estimated incident rate ratios (IRRs) of hospitalization for race- and sex-specific quartiles of each muscle and function parameter separately. Multivariate models adjusted for age, body mass index, health status, and coexisting medical conditions.
RESULTS: During an average 4.7 years of follow-up, 1,678 (55.7%) participants experienced one or more hospitalizations. Participants in the lowest quartile of muscle density were more likely to be subsequently hospitalized (multivariate IRR=1.47, 95% confidence interval (CI)=1.24–1.73) than those in the highest quartile. Similarly, participants with the weakest grip strength were at greater risk of hospitalization (multivariate IRR=1.52, 95% CI=1.30–1.78, Q1 vs. Q4). Comparable results were seen for knee strength, walking pace, and chair stands pace. Lean mass and muscle area were not associated with risk of hospitalization.
CONCLUSION: Weak strength, poor function, and low muscle density, but not muscle size or lean mass, were associated with greater risk of hospitalization. Interventions to reduce the disease burden associated with sarcopenia should focus on increasing muscle strength and improving physical function rather than simply increasing lean mass.  相似文献   
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BACKGROUND: Prenatal alcohol exposure affects brain structure and function. This study examined brain metabolism using magnetic resonance spectroscopy (MRS) and searched for regions of specific vulnerability in adolescents and young adults prenatally exposed to alcohol. METHODS: Ten adolescents and young adults with confirmed heavy prenatal alcohol exposure and a diagnosis within the fetal alcohol spectrum disorders (FASD) were included. Three of them had fetal alcohol syndrome (FAS), 3 had partial FAS (PFAS), and 4 had alcohol-related neurobehavioral disorder (ARND). The control group consisted of 10 adolescents matched for age, sex, head circumference, handedness, and body mass. Exclusionary criteria were learning disorders and prenatal alcohol exposure. Three-dimensional (1)H magnetic resonance spectroscopic imaging ((1)H MRSI) was performed in the cerebrum and cerebellum. Metabolite ratios N-acetylaspartate/choline (NAA/Cho), NAA/creatine (Cr) and Cho/Cr, and absolute metabolite intensities were calculated for several anatomic regions. RESULTS: In patients with FASD, lower NAA/Cho and/or NAA/Cr compared with controls were found in parietal and frontal cortices, frontal white matter, corpus callosum, thalamus, and cerebellar dentate nucleus. There was an increase in the absolute intensity of the glial markers Cho and Cr but no change in the neuronal marker NAA. CONCLUSIONS: Our results suggest that prenatal alcohol exposure alters brain metabolism in a long-standing or permanent manner in multiple brain areas. These changes are in accordance with previous findings from structural and functional studies. Metabolic alterations represent changes in the glial cell pool rather than in the neurons.  相似文献   
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Bullying at work, health outcomes, and physiological stress response   总被引:1,自引:0,他引:1  
The relationships among bullying or witnessing bullying at work, self-reported health symptoms, and physiological stress reactivity were analysed in a sample of 437 employees (294 women and 143 men). Physiological stress reactivity was measured as cortisol in the saliva. Of the respondents, 5% of the women (n=15) and 5% of the men (n=7) reported bullying, whereas 9% of the women (n=25) and 11% of the men (n=15) had witnessed bullying at work. The results indicated that the bullied respondents had lower social support from coworkers and supervisors, and they reported more symptoms of somatisation, depression, anxiety, and negative affectivity (NA) than did the nonbullied respondents. Witnesses reported more symptoms of anxiety and lower support from supervisor than did the nonbullied employees. Concentrations of cortisol in the saliva were lower at awakening in bullied respondents compared with nonbullied respondents. Previous studies have reported lower diurnal concentration of cortisol for people with posttraumatic stress disorder (PTSD) and chronic fatigue. To our knowledge, this is the first full study on the associations among being subjected to bullying, health outcomes, and physiological stress response.  相似文献   
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OBJECTIVES: Alveolar macrophages (AM) are used as a biomarker of pulmonary irritation due to occupational exposure in the AM test. The aim of this study was to investigate whether there is a co-variation between the number of AM and exposure to cooking fumes. MATERIALS AND METHODS: The study group consisted of 62 volunteers. People who worked in a kitchen preparing hot meals were considered as occupationally exposed (35 persons). The exposed group was further divided into highly and slightly exposed persons according to the levels of fat aerosols and aldehydes in the working atmosphere. People who were not preparing hot meals were considered as unexposed (27 persons). The number of AM was counted in smears prepared from expectorate samples from each participant. Samples were taken on three different days. RESULTS: Highly occupationally exposed persons had a higher number of AM in their samples than both slightly occupationally exposed persons and unexposed persons. Highly exposed smokers had a statistically significantly higher number of AM compared with both slightly and unexposed smokers (P < or = 0.05). CONCLUSION: The results suggest an increase in the number of AM due to exposure to cooking fumes and a synergistic effect between occupational exposure and smoking.  相似文献   
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Cytochrome P4501A (CYP1A) induction and DNA adduct formation were evaluated in the rat hepatoma cell line Fao, as biomarkers of exposure to organic compounds. Cells were exposed to environmentally relevant concentrations of benzo[a]pyrene (B[a]P) or 3,3',4,4'-tetrachlorobiphenyl (TCB), and to combinations of B[a]P and TCB. Both B[a]P and TCB induced CYP1A proteins in a concentration-dependent relationship, up to concentrations of 10 and 1 μM, respectively, detected by Western blotting. DNA adducts, analyzed by (32)P-postlabeling, were found at the highest concentrations of B[a]P (1 and 10 μM). No adducts were found in cells exposed to 0.1 μM TCB alone. The cotreatment of TCB and B[a]P indicated an increase in DNA adduct formation, compared with B[a]P, but no further induction of CYP1A protein compared with TCB alone. This study suggests that Western blotting and (32)P-postlabeling might be suitable methods for detecting CYP1A protein induction and DNA adducts, respectively, after exposure to environmentally relevant concentrations of organic compounds.  相似文献   
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