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11.
Objective: Previous research has addressed the relationship between BMI and chronic disease in primary care; however, little has been done with regard to the association between obesity and depression in primary care. The purpose of this paper is to assess the relationship between obesity and chronic conditions including depression. Research Methods and Procedures : Data from primary care patients seen at a university‐based family medicine clinic in the southeastern United States were extracted for the time between January 1, 1999 and January 1, 2002. Data extracted included most recent height and weight, age, ethnicity, pregnancy status, number of office visits, blood pressure, cholesterol, hemoglobin A1C, current diagnoses, and medications. Results : A total of 8197 patients were included in the analysis. Sixty‐nine percent of patients seen in a 3‐year period were either overweight or obese. Comparing blood pressure, cholesterol, diagnoses, and medications between BMI groups found differences in virtually all categories. Diagnoses of high cholesterol, hypertension, diabetes, and depression significantly increased for obese patients. Discussion : Obese patients are over‐represented in primary care, and this over‐representation of obesity correlates with several diagnoses, including depression. Depression is a chronic disease that may interfere with health‐related behaviors and must be addressed within the health care system.  相似文献   
12.
Accurately estimating infection prevalence is fundamental to the study of population health, disease dynamics, and infection risk factors. Prevalence is estimated as the proportion of infected individuals (“individual‐based estimation”), but is also estimated as the proportion of samples in which evidence of infection is detected (“anonymous estimation”). The latter method is often used when researchers lack information on individual host identity, which can occur during noninvasive sampling of wild populations or when the individual that produced a fecal sample is unknown. The goal of this study was to investigate biases in individual‐based versus anonymous prevalence estimation theoretically and to test whether mathematically derived predictions are evident in a comparative dataset of gastrointestinal helminth infections in nonhuman primates. Using a mathematical model, we predict that anonymous estimates of prevalence will be lower than individual‐based estimates when (a) samples from infected individuals do not always contain evidence of infection and/or (b) when false negatives occur. The mathematical model further predicts that no difference in bias should exist between anonymous estimation and individual‐based estimation when one sample is collected from each individual. Using data on helminth parasites of primates, we find that anonymous estimates of prevalence are significantly and substantially (12.17%) lower than individual‐based estimates of prevalence. We also observed that individual‐based estimates of prevalence from studies employing single sampling are on average 6.4% higher than anonymous estimates, suggesting a bias toward sampling infected individuals. We recommend that researchers use individual‐based study designs with repeated sampling of individuals to obtain the most accurate estimate of infection prevalence. Moreover, to ensure accurate interpretation of their results and to allow for prevalence estimates to be compared among studies, it is essential that authors explicitly describe their sampling designs and prevalence calculations in publications.  相似文献   
13.
Objectives: To establish BMI percentiles and cutoffs for underweight, overweight, and obesity in South Korean schoolgirls. Research Methods and Procedures: A total of 1229 South Korean schoolgirls aged 8 to 18 years were randomly selected to complete a self‐administered questionnaire. BMI charts and cutoffs were constructed after analyzing data from 1107 subjects. Percentile curves were established by the modified LMS method. Results: The percentiles for underweight, overweight, and obesity corresponding to BMI of 18.5, 23.0, and 25.0 kg/m2 at age 18 were the 13.0th percentile, the 77.8th percentile, and the 91.2nd percentile, respectively. The corresponding prevalences of underweight, overweight, and obesity were 12.1, 12.5, and 9.8%, respectively. Discussion: We established for the first time, to our knowledge, new BMI cutoffs for ages 8 to 18 that corresponded to BMIs of 18.5, 23.0, and 25.0 kg/m2 for Asian adults designated by the International Obesity Task Force. These newly established BMI cutoffs might help to estimate the prevalence of overweight and obesity in Asian children.  相似文献   
14.
高温与香烟联合对大鼠早期胚胎致畸作用的研究   总被引:4,自引:0,他引:4  
为了探讨高温与香烟联合对胚胎的毒性和致畸作用,用高温(40、41、42、43℃)及香烟烟不溶4物联合处理怀孕的大鼠。结果表明,高温与香烟联合可加强胚胎的致畸作用,并与温度、香烟浓度和高温持续时间明显相关,当持续3分钟的高温与香烟联合,胚胎致畸率达70%以上,与单独高温组、单独给烟组有明显差异(P〉0.01),并具有协同效应。结果提示,持续高温与香烟联合有明显的胚胎毒性和致畸作用。  相似文献   
15.
Epigenetic modifications to peripheral white blood cell DNA occur in response to a wide variety of exposures. In prior work, we and others have shown that broad changes in DNA methylation, particularly at the aryl hydrocarbon receptor repressor (AHRR) locus, occur in samples from subjects with long histories of smoking. However, given the large number of epigenetic changes that occur in response to prolonged smoking, the primacy of the response at AHRR and the sensitivity of these changes to low levels of smoking are not known. Therefore, we examined the association of smoking to genome lymphocyte DNA methylation status in a representative sample of 399 African American youths living in the rural South that includes 72 subjects with less than one half-pack year of exposure. Consistent with our prior findings, we found a stepwise effect of smoking on DNA methylation among youth with relatively brief exposure histories at a CpG residue in AHRR (cg05575921) (FDR corrected p values; 3 × 10−7 and 0.09 in the male and female samples, respectively) that was identified in previous studies and at which the effects of smoking were significant, even in those subjects with less than one half pack year exposure. We conclude that AHRR demethylation at cg05575921 in peripheral cells may serve as an early, sensitive biomarker for even low levels of exposure to tobacco smoke, providing a non-self-report alternative for nascent exposure to tobacco smoke. We also suggest that the AHRR/AHR pathway may be functional in the response of peripheral white blood cells to tobacco smoke exposure.  相似文献   
16.
Aims:  To determine Legionella pollution prevalence, describe the amount of Legionellae with respect to temperature in Shanghai cooling tower water (CTWs) in various types of public sites.
Methods and Results:  Six urban districts were selected as the study fields, adopting multiple-phase sampling methods. Routine culture was used to identify Legionellae. Of the samples, 58·9% (189/321) were observed to be positive, 19·9% were isolated over 100 CFU ml−1. Legionella pneumophila serogroup 1 was the most frequently isolated species (155/189, 82·0%), followed by Leg. micdadei that was at the second place (44/189, 23·3%). The mean CFU ml−1 of Legionellae in CTWs reached its peak from July to September. Over all 15·4% of the samples exceeding 100 CFU ml−1 were observed in a hospital setting.
Conclusions:  The prevalence of Legionella pollution in CTWs, especially in CTWs of subway stations and hospitals, is worrying, and the positive rate and CFU ml−1 of Legionellae in CTWs have a close relationship with air temperature.
Significance and Impact of the Study:  The study demonstrates pollution prevalence rates in different types of sites and various seasons, and provides a proportion of different serogroups of Legionellae . It illuminates an urgent need for dealing with the potential risk of legionellosis in Shanghai, through improved control and prevention strategies.  相似文献   
17.
As explained by Kitchener in a previous issue of Cytopathology (2015; 26 :4‐6), primary human papillomavirus (HPV) testing is likely to be introduced in the UK for all women aged 25–64 years following pilot site studies already in place. This will be necessary when the prevalence of cervical cancer and its precursors declines when vaccination takes effect but there is a risk in abandoning cytology as a primary test: a risk that would be most apparent in the present unvaccinated population in which the prevalence of cervical cancer and its precursors is exceptionally high. HPV testing is more sensitive than cytology but has a significant false‐negative rate that could be detrimental to a successful screening programme if introduced without cytology backup. Accurate cytology would be needed for triage and could be compromised if HPV‐negative tests were excluded from examination. This article proposes a compromise: cytology and HPV co‐testing for the first two screening tests to optimise the sensitivity of the test as a whole. Registrations of invasive and in situ carcinoma of the uterine cervix in England indicate that the prevalence of the disease is highest in young women in the early rounds of screening. Calculations of the likely impact on the workload of this proposal have been based on a service evaluation of 295 cytology tests received at St Thomas’ Hospital, which suggests that the volume of cytology tests would be reduced by approximately 60% compared with 80% for primary HPV testing alone. This proposal should be debated openly before irrevocable changes are made to a skilled workforce.  相似文献   
18.

Background

Exhaled breath condensate collection is a non-invasive method of sampling the respiratory tract that can be repeated several times in a wide range of clinical settings. Quantitation of non-volatile compounds in the condensate requires highly sensitive analytical methods, e.g. mass spectrometry.

Objective

To validate cross-platform measurements of eicosanoids using high performance liquid chromatography or gas chromatography coupled with mass spectrometry in exhaled breath condensate sampled from 58 healthy individuals.

Methods

Twenty different eicosanoid compounds, representing major arachidonic acid lipoxygenation and cyclooxygenation pathways were measured using a stable isotope dilution method. We applied a free palmitic acid concentration as a surrogate marker for the condensate dilution factor.

Results

Eicosanoids concentrations in the condensates were consistent with their content in other biological fluids. Prostaglandin E2 was the most abundant mediator, represented by its stable metabolite tetranor-PGEM. Prostaglandin D2 products were at low concentration, while hydroxyacids derived from lipoxygenation were abundant. 5-HETE was elevated in current tobacco smokers. Leukotriene B4 has the highest concentration of all 5-LO products. 15-LO analogues of cysteinyl leukotrienes–eoxins were detectable and metabolized to eoxin E4. Two main vascular prostanoids: prostacyclin and thromboxane B2 were present as metabolites. A marker for non-enzymatic lipid peroxidation, 8-iso-PGF isoprostane was increased in smokers.

Conclusion

Presented targeted lipidomics analysis of exhaled breath condensate in healthy subjects justifies its application to investigation of inflammatory lung diseases. Measurements of non-volatile mediators of inflammation in the condensates might characterize disease-specific pathological mechanisms and responses to treatment.  相似文献   
19.
A large-scale survey was conducted to investigate the infection status of fresh water fishes with Clonorchis sinensis metacercariae (CsMc) in 3 wide regions, which were tentatively divided by latitudinal levels of the Korean peninsula. A total of 4,071 freshwater fishes were collected from 3 regions, i.e., northern (Gangwon-do: 1,543 fish), middle (Chungcheongbuk-do and Gyeongsangbuk-do: 1,167 fish), and southern areas (Jeollanam-do, Ulsan-si, and Gyeongsangnam-do: 1,361 fish). Each fish was examined by the artificial digestion method from 2003 to 2010. In northern areas, only 11 (0.7%) fish of 2 species, Pungtungia herzi and Squalidus japonicus coreanus from Hantan-gang, Cheolwon-gun, Gangwon-do were infected with av. 2.6 CsMc. In middle areas, 149 (12.8%) fish were infected with av. 164 CsMc. In southern areas, 538 (39.5%) fish were infected with av. 159 CsMc. In the analysis of endemicity in 3 regions with an index fish, P. herzi, 9 (6.2%) of 146 P. herzi from northern areas were infected with av. 2.8 CsMc. In middle areas, 34 (31.8%) of 107 P. herzi were infected with av. 215 CsMc, and in southern areas, 158 (92.9%) of 170 P. herzi were infected with av. 409 CsMc. From these results, it has been confirmed that the infection status of fish with CsMc is obviously different among the 3 latitudinal regions of the Korean peninsula with higher prevalence and burden in southern regions.  相似文献   
20.
Cryptosporidium , a protozoan parasite that causes watery diarrhea, is found worldwide and is common in areas with low water hygiene. In February 2014, 866 stool samples were collected from the inhabitants of 2 rural areas in White Nile State, Sudan. These stool samples were assessed by performing modified acid-fast staining, followed by examination under a light microscope. The overall positive rate of Cryptosporidium oocysts was 13.3%. Cryptosporidium oocysts were detected in 8.6% stool samples obtained from inhabitants living in the area having water purification systems and in 14.6% stool samples obtained from inhabitants living in the area not having water purification systems. No significant difference was observed in the prevalence of Cryptosporidium infection between men and women (14.7% and 14.1%, respectively). The positive rate of oocysts by age was the highest among inhabitants in their 60s (40.0%). These findings suggest that the use of water purification systems is important for preventing Cryptosporidium infection among inhabitants of these rural areas in Sudan.  相似文献   
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