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991.
Coffey CC Pearce TA Lawrence RB Hudnall JB Slaven JE Martin SB 《Journal of occupational and environmental hygiene》2009,6(1):1-8
The performance of field portable direct-reading organic vapor monitors (DROVMs) was evaluated under a variety of experimental conditions. Four of the DROVMs had photoionization detectors (ppbRAE, IAQRAE, MultiRAE, and Century Toxic Vapor Analyzer), one had a flame ionization detector (Century Toxic Vapor Analyzer), and one was a single-beam infrared spectrophotometer (SapphIRe). Four of each DROVM (two Century Toxic Vapor Analyzers and SapphIRes) were tested. The DROVMs were evaluated at three temperatures (4 degrees C, 21 degrees C, and 38 degrees C), three relative humidities (30%, 60%, and 90%), and two hexane concentrations (5 ppm and 100 ppm). These conditions were selected to provide a range within the operational parameters of all the instruments. At least four replicate trials were performed across the 18 experimental conditions (3 temperatures x 3 relative humidities x 2 concentrations). To evaluate performance, the 4-hr time-weighted average readings from the DROVMs in a given trial were compared with the average of two charcoal tube concentrations using pairwise comparison. The pairwise comparison criterion was +/-25% measurement agreement between each individual DROVM and the DROVMs as a group and the average charcoal tube concentration. The ppbRAE group performed the best with 40% of all readings meeting the comparison criterion followed by the SapphIRe group at 39%. Among individual DROVMs, the best performer was a SapphIRe, with 57% of its readings meeting the criterion. The data was further analyzed by temperature, humidity, and concentration. The results indicated the performance of some DROVMs may be affected by temperature, humidity, and/or concentration. The ppbRAE group performed best at 21 degrees C with the percentage of readings meeting the criterion increasing to 63%. At the 5 ppm concentration, 44% of the ppbRAE group readings met the criterion, while at 100 ppm, only 35% did. The results indicate that monitors can be used as survey tools. Based on the data, the inconsistent performance of these DROVMs may not allow them to be used for determining compliance with occupational exposure limits. 相似文献
992.
Differential locational access to fast-food retailing between neighbourhoods of varying socioeconomic status has been suggested as a contextual explanation for the social distribution of diet-related mortality and morbidity. This New Zealand study examines whether neighbourhood access to fast-food outlets is associated with individual diet-related health outcomes. Travel distances to the closest fast-food outlet (multinational and locally operated) were calculated for all neighbourhoods and appended to a national health survey. Residents in neighbourhoods with the furthest access to a multinational fast-food outlet were more likely to eat the recommended intake of vegetables but also be overweight. There was no association with fruit consumption. Access to locally operated fast-food outlets was not associated with the consumption of the recommended fruit and vegetables or being overweight. Better neighbourhood access to fast-food retailing is unlikely to be a key contextual driver for inequalities in diet-related health outcomes in New Zealand. 相似文献
993.
Luc H Pham Thuy B Au Leigh Blizzard Nhan B Truong Michael D Schmidt Robert H Granger Terence Dwyer 《BMC public health》2009,9(1):291
Background
Despite the increasing burden of non-communicable diseases (NCD) in Vietnam, information on the prevalence of preventable risk factors for NCD is restricted to the main urban centres of Ha Noi, and Ho Chi Minh City (HCMC). This population-based survey aimed to describe the prevalence of risk factors for NCD in a rural Vietnamese sample. 相似文献994.
995.
ObjectiveTo examine the prevalence and correlates of substance use during pregnancy among women in the United States.MethodsWe analyzed data from pregnant (n = 1800) and non-pregnant women (n = 37,527) aged 15–44 years who participated in the 2002 or 2003 National Survey on Drug Use and Health, a nationally representative epidemiologic survey. Study variables included demographics, any substance use in the prior 30 days, and possible current psychopathology. Data were analyzed using weighted chi-square and multiple logistic regressions that accounted for the complex survey design.ResultsThe overall prevalence of any past month substance use during pregnancy was 25.8%; the prevalence rates of past month illicit drug, cigarette and alcohol use were 4.7%, 18.9% and 10%, respectively. Compared to the prevalence of substance use among women in their first trimester, use was significantly lower among women in their second or third trimesters. Women who reported using substances during pregnancy were significantly more likely to meet the criteria for possible current psychopathology and be White. Additionally, women who were employed, married, and in their second or third trimester compared to the first were significantly less likely to have used any substance during pregnancy, adjusting for age, ethnicity and income.ConclusionsAlthough the prevalence of substance use among pregnant women was significantly lower than non-pregnant women, some groups of women remain vulnerable to continued use, including those who are unemployed, unmarried, and experiencing possible current psychopathology. Prevention and intervention programs aimed at high-risk populations are warranted to reduce the deleterious effects of substance use on pregnancy outcomes. 相似文献
996.
Decreased FGF8 signaling causes deficiency of gonadotropin-releasing hormone in humans and mice 下载免费PDF全文
Falardeau J Chung WC Beenken A Raivio T Plummer L Sidis Y Jacobson-Dickman EE Eliseenkova AV Ma J Dwyer A Quinton R Na S Hall JE Huot C Alois N Pearce SH Cole LW Hughes V Mohammadi M Tsai P Pitteloud N 《The Journal of clinical investigation》2008,118(8):2822-2831
Idiopathic hypogonadotropic hypogonadism (IHH) with anosmia (Kallmann syndrome; KS) or with a normal sense of smell (normosmic IHH; nIHH) are heterogeneous genetic disorders associated with deficiency of gonadotropin-releasing hormone (GnRH). While loss-of-function mutations in FGF receptor 1 (FGFR1) cause human GnRH deficiency, to date no specific ligand for FGFR1 has been identified in GnRH neuron ontogeny. Using a candidate gene approach, we identified 6 missense mutations in FGF8 in IHH probands with variable olfactory phenotypes. These patients exhibited varied degrees of GnRH deficiency, including the rare adult-onset form of hypogonadotropic hypogonadism. Four mutations affected all 4 FGF8 splice isoforms (FGF8a, FGF8b, FGF8e, and FGF8f), while 2 mutations affected FGF8e and FGF8f isoforms only. The mutant FGF8b and FGF8f ligands exhibited decreased biological activity in vitro. Furthermore, mice homozygous for a hypomorphic Fgf8 allele lacked GnRH neurons in the hypothalamus, while heterozygous mice showed substantial decreases in the number of GnRH neurons and hypothalamic GnRH peptide concentration. In conclusion, we identified FGF8 as a gene implicated in GnRH deficiency in both humans and mice and demonstrated an exquisite sensitivity of GnRH neuron development to reductions in FGF8 signaling. 相似文献
997.
Gaedigk A Simon SD Pearce RE Bradford LD Kennedy MJ Leeder JS 《Clinical pharmacology and therapeutics》2008,83(2):234-242
Inferring CYP2D6 phenotype from genotype is increasingly challenging, considering the growing number of alleles and their range of activity. This complexity poses a challenge in translational research where genotyping is being considered as a tool to personalize drug therapy. To simplify genotype interpretation and improve phenotype prediction, we evaluated the utility of an "activity score" (AS) system. Over 25 CYP2D6 allelic variants were genotyped in 672 subjects of primarily Caucasian and African-American heritage. The ability of genotype and AS to accurately predict phenotype using the CYP2D6 probe substrate dextromethorphan was evaluated using linear regression and clustering methods. Phenotype prediction, given as a probability for each AS group, was most accurate if ethnicity was considered; among subjects with genotypes containing a CYP2D6*2 allele, CYP2D6 activity was significantly slower in African Americans compared to Caucasians. The AS tool warrants further prospective evaluation for CYP2D6 substrates and in additional ethnic populations. 相似文献
998.
Pucci A Brscic E Tessitore E Celeste A Crudelini M De Bernardi A Alberti A Biondi-Zoccai G Sheiban I 《European journal of clinical investigation》2008,38(5):281-289
Background C‐Reactive Protein (CRP) is considered a predictive factor for cardiovascular events and its serum levels have been shown to correlate with thin cap coronary plaques in sudden coronary death. Whether serum CRP levels are associated with in vivo atherothrombotic features is unclear. We thus analysed samples from coronary atherectomy specimens obtained during percutaneous coronary intervention. Materials and methods Patients with coronary artery disease undergoing directional atherectomy, distinguished by unstable versus stable coronary syndrome diagnosis, provided coronary specimens from culprit lesions. Assessment was conducted by means of conventional histology, morphometry and immunohistochemistry. Specific antibodies against erythrocyte‐specific protein glycophorin A, endothelial and macrophage antigens were also used. Results There were 51 patients with unstable coronary disease and 47 patients with stable angina. Serum CRP levels ≥ 1 mg L?1 were detected in 24/98 patients, and were significantly associated with hypercellularity, macrophage infiltrates, neoangiogenesis and intraplaque haemorrhage (all P < 0·05). Furthermore, coronary plaques from patients with unstable angina contained larger atheromas, more hypercellular plaques, with abundant macrophages, neoangiogenesis and intraplaque haemorrhages and lesser fibrous tissue (all P < 0·05). Conclusions We observed a positive correlation between increased serum CRP levels and typical pathological features of complex atherothrombotic coronary disease, confirming in vivo the mechanistic role of CRP in coronary atherothrombosis. 相似文献
999.
While many have suggested that prevention is key regarding sun over exposure, individuals (including children) still frequently experience sunburn. The Skin Cancer Foundation (2008) reported that 42% of individuals polled endured at least one sunburn per year. Furthermore, the Centers for Disease Control and Prevention (CDC) reports indicate that the incidence of sunburn rose from 31.8% in 1999 to 33.7% in 2004 (CDC, 2007). Children are more susceptible to skin damage because their skin is more sensitive than the skin of adults and it burns more easily (The Skin Cancer Foundation, 2008). Other risk factors include a fair complexion, found commonly in people with blueor green eyes, freckles, and light-colored hair (The Skin Cancer Foundation, 2008). 相似文献
1000.
During a 2-year period from 2004 and 2005, emergency departments treated over 1,500 children under the age of 2 years for adverse events related to over-the-counter (OTC) cough and cold medication use; these incidents include 3 infant deaths. The risk of overdose, incorrect dosing and adverse events is increased in young children due to the greater number of colds they acquire each year. Lack of evidence to support the use of OTC medications in young children is well documented in the literature; however, people continue to use OTC medications with young children. The common cold is generally a mild, self-limited illness that usually improves with time. Recommended care and treatment for the common cold includes symptomatic treatment. This article presents and reviews the available evidence regarding the use of OTC cough and cold medications for pediatric healthcare providers. This review of the evidence will be helpful for healthcare providers to minimize risks to young children who intentionally or unintentionally ingest these medications and to educate child caregivers regarding proper use of OTC cough and cold medications with children. 相似文献