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51.
This study examines the locations of family homes, medical schools and places of specialist training, and work of doctors qualifying from UK medical schools in 5 calendar years between 1974 and 1993. The contribution of each UK region to the medical workforce relative to its population is assessed and trends over time are examined. The relationship between place of family home and medical school attended is examined for 14,108 doctors. Career appointment location and its relationship to medical school and family home loc‐ation are examined for over 4000 doctors. For the qualifiers of 1983, an additional analysis incorporating place of training is included. Large differences were found in the percentage of medical students from local family homes attending each regional medical school. In some cases differences reflected local populations but other cases had no obvious cause. Over all cohorts studied, 38% of respondents attended a medical school in the region of their family home (32% of 1993 qualifiers), 42% held a career post in the same region as their medical school, and 38% held a career post in the same region as their family home. Among the qualifiers of 1983, 65% had a career post in the same region as their postgraduate training, 34% also attended medical school in the same region, and 19% also came from family homes in the same region. More women than men took up a career post in the same region as their postgraduate training. The relationships to family home and medical school did not differ by gender. Consultants appeared slightly less likely than GPs to have stayed within a region, but this difference was not statistically significant.  相似文献   
52.
This research is designed to evaluate a number of biological markers to estimate harmful exposure on coal miners from different mining regions in France and to relate the outcome to differences in prevalence of coal worker pneumoconiosis (CWP) between these regions. Eight epidemiological groups of active and ex-miners (smokers and non-smokers) have been selected in the French collieries (North, Lorraine and Provence) according to their occupational and pneumoconiotic status. The following biomarkers have been evaluated: cellularity of sputum, elementary analysis of particles in TEM/EDAX, plasma neutral metalloendo peptidase elastase type (NMEP), leucocyte elastase (HLE), fibronectin (FN) and elastin peptides. Pulmonary alveolitis, expressed by sputum cellularity, is different between active workers groups but not related to the general background of pneumoconiosis prevalence in the French collieries. In the plasma parameters, fibronectin, HLE and NMEP significantly increased in all groups of coal mine workers as compared to the control group, except for fibronectin parameter in Lorraine collierie. The degree of increase of these parameters allow us to discriminate the different groups and suggest that plasma FN, HLE and NMEP may be considered as biological markers of chronic inhalation of coal mine dust particles. The decrease of elastin peptides level in the Lorraine group alone suggests a specific alteration of elastin metabolism. These parameters were not related to the development of pneumoconiosis and its degree of severity.  相似文献   
53.
 Dermal exposures of methanol were administered in a clinical study designed to compare several biological indicators. Four subjects were exposed in five exposure sessions of varying length. In each session, a sequence of measurements of methanol concentrations in blood, breath, and headspace samples of air at exposed and unexposed skin were collected before and after dermal exposures. Skin headspace samples, collected in gas sampling bags, were designed to reflect equilibrium skin: air partitioning. At exposed skin, headspace samples were highly elevated for at least 8 h following exposure, indicating the presence of a methanol reservoir in skin. After exposure, methanol concentrations at exposed skin showed a rapid initial decline, then a slower first-order decrease. Methanol concentrations were clearly detectable in headspace samples at unexposed skin. Substantial transfer from exposed skin occurred due to mechanical contact and washing. When transfer was restricted, surface concentrations at unexposed skin were similar to levels in breath and were strongly correlated to methanol concentrations in blood. While results are preliminary due to the small sample sizes and several unresolved experimental issues, the simple, rapid, and noninvasive skin headspace measurements appear useful as a biological exposure indicator that clearly shows the presence and site of a dermal exposure, and measurements at unexposed skin reflect concentrations in blood. Received: 14 March 1995/Accepted: 3 November 1995  相似文献   
54.
As part of the strategy for the design of macromolecular carriers for drug targeting, the disposition characteristics of macromolecules were studied in mice bearing tumors that served as target tissues. Eight kinds of macromolecules including four polysaccharides and four proteins with different molecular weights and electric charges were used; tissue distribution and tumor localization after intravenous injection were studied. Pharmacokinetic analysis revealed that the tissue radioactivity uptake rate index calculated in terms of clearance was different among the tested compounds; especially, the urinary radioactivity excretion clearances and the total hepatic radioactivity uptake clearances varied widely. Compounds with low molecular weights (approximately 10 kD) or positive charges showed lower tumor radioactivity accumulation; radioactivity was rapidly eliminated from the plasma via rapid urinary excretion or extensive hepatic uptake, respectively. On the other hand, large and negatively charged compounds, carboxymethyl dextran, bovine serum albumin, and mouse immunoglobulin G, showed higher radioactivity accumulation in the tumor (calculated total amounts were 15.6, 10.8, and 20.8% of the dose, respectively) and prolonged retention in the circulation. These results demonstrated that the total systemic exposure rather than the uptake rate index was correlated with total tumor uptake. Molecular weight and electric charge of the macromolecules significantly affected their disposition characteristics and, consequently, determined radioactivity accumulation in the tumor. It was concluded that a drug–carrier complex designed for systemic tumor targeting should be polyanionic in nature and larger than 70,000 in molecular weight.  相似文献   
55.
Summary Analysis of hemoglobin adducts in blood samples is suitable for the biological monitoring of genotoxic chemicals. The method is specific because the compound to which the individual was exposed is identified. The sensitivity of the method depends on the analytical procedure applied, but is hardly limiting since large amounts of the protein can be obtained. The method provides not only information about the internal exposure to the environmental chemical, but also about the individual's capacity to generate ultimate genotoxic metabolites from it. Since macromolecular damage in blood cells is correlated to that in potential target tissues, this information is relevant to risk assessment, insofar as macromolecular damage produced by a specific chemical can be correlated with the development of tumors.  相似文献   
56.
The authors present the third installment of the guidelines and recommendations from the Safety Committee of the Society for Magnetic Resonance Imaging (now the Society of Magnetic Resonance) concerning various issues related to the safety and management of patients undergoing magnetic resonance (MR) procedures. This document was developed to provide standardized and consistent information for use by health practitioners involved in screening patients or other individuals for MR procedures.  相似文献   
57.
目的:了解射击运动员高脂血症的发生情况和可能的引发因素,为预防高脂血症提供依据。方法:对从事专业训练半年以上,无急慢性疾病的53名省级优秀射击运动员进行膳食调查和血清脂质水平检测。结果:运动员的高脂血症检出率为28.3%,全部为高甘油三脂血症;膳食中 运动员除了摄入维生素B1、B2不足和维生素A缺乏外,其他各类营养素基本能满足机体需要,属基本合理膳食。结论:以抗阻训练和静力运动为运动特征的射击运动,可能会对机体血脂代谢产生不利的影响。  相似文献   
58.
郑州市1996~2005年梅毒流行病学分析   总被引:7,自引:0,他引:7  
目的寻求郑州市梅毒流行规律和特点,为制订防治政策提供依据。方法对1996~2005年郑州市梅毒病例资料进行分析。结果1996~2005年梅毒的发病率呈上升趋势。以早期梅毒为主,一期梅毒发病数高于二期梅毒;梅毒感染者主要在20~44岁年龄段,占60.05%;工人、农民、待业、商业服务、干部分别占20.44%,18.15%,11.52%,8.54%,6.25%。结论应加强梅毒防治工作力度,规范梅毒诊治,全面实施健康教育、行为干预等综合防治措施。  相似文献   
59.
BACKGROUND: Asking psychiatric in-patients about their drug consumption is unlikely to yield reliable results, particularly where alcohol and illicit drug use is involved. The main aim of this study was to compare spontaneous self-reports of drug use in hospitalized psychiatric patients to biological measures of same. A secondary aim was to determine which personal factors were associated with the use of tobacco, alcohol, and illicit drugs as indicated by these biological measures. METHODS: The consumption of substances was investigated using biological measures (urine cotinine, cannabis, opiates, cocaine, amphetamines and barbiturates; blood carbohydrate-deficient transferrin [CDT] and gamma-glutamyl transferase [GGT]) in 486 consecutively admitted psychiatric patients, one day following their hospitalization. Patients' self-reports of alcohol, tobacco and illicit drugs consumption were recorded. Socio-professional and familial data were also recorded. RESULTS: The results show a low correlation between biological measures and self-reported consumption of alcohol and illicit drugs. Fifty-two percent of the patients under-reported their consumption of illicit drugs (kappa=.47). Patients with schizophrenia and personality disorders were more likely to disclose their illicit drug consumption relative to patients suffering from mood disorders and alcohol dependence. Fifty-six percent of patients underreported alcohol use, as evaluated by CDT (kappa=.2), and 37% underreported when using the CDT+GGT measure as an indicator. Smoking appeared to be reported adequately. In the study we observed a strong negative correlation between cannabis use and age, a strong correlation between tobacco and cannabis use, and correlations between tobacco, cannabis and alcohol consumption. CONCLUSION: This study is the first to compare self-reports and biological measures of alcohol, tobacco and illicit drug uses in a large sample of inpatients suffering from various categories of psychiatric illnesses, allowing for cross-diagnosis comparisons.  相似文献   
60.
北宋名医吴本的精湛医术和高尚医德在漳州、泉州和台南民众中久为传颂,流感在慈济宫的“济世仙方药鉴”是现存有关吴本的宝贵医药资料,该药签体现了中医的选方特点和用药特点,今天仍有整理研究的价值。  相似文献   
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