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81.
BACKGROUND: South Africa offers a valuable study environment to assess the impact of political and social changes on health. Increasing urbanisation has led to a focus on city development and its effect on its residents. The study assesses whether sex- and race-specific suicide rates differ across six of South Africa's major cities. Regional differences may reflect varying contextual and individual underlying mechanisms. Those need to be understood for appropriately targeted prevention efforts. METHODS: Suicide mortality data (n=4,946) for the six cities between 2001 and 2003 were used to assess whether there are differences in rates for age-standardised race and sex groups across cities and whether these differences are constant across cities. The overall age-standardised rates for the six cities was 25.3/100,000 for men and 5.6/100,000 for women. RESULTS: Suicide rates are most often highest among whites and men, but both the magnitude and distribution of suicide vary considerably for different race and sex groups within and across cities. There is a strong association between the method of suicide used and the city. CONCLUSIONS: Despite some common trends in the suicide profile across South African cities, city does matter for the magnitude and distribution of suicide mortality across race and sex groups and for the method of suicide used. The need for locally based suicide research investigating possible reasons for these differences is highlighted.  相似文献   
82.
Indications for interventional radiology have increased, and various arterial and venous procedures are nowadays possible in oncology. Besides emergency procedures, scheduled palliative or curative procedures require multidisciplinary cooperation emphasizing on cautions related to iodine contrast media and concerning immunosuppresion, hemostasis disorders, analgesia, and the choice of the adequate approach. Diagnostic endovascular biopsies and venous sampling may be performed. Embolisation procedures are useful for achieving hemostasis, tumor devascularisation, or chemo-embolisation. Revascularisation procedures concern central vein obstructions, catheter occlusion or arterial stenoses and occlusions. Vena cava filtering, retrieval of intravascular foreign bodies and percutaneous implantation of ports can also be indicated, as well other treatments of central venous access complications. The principles, technical aspects, results, and indications of these various endovascular procedures are described in this review.  相似文献   
83.
This article reviews aspects of the mental health care of migrant and refugee children. It highlights the challenges of access to care for these children and of considering the role of pediatricians in their mental health care. It also looks at the sources of differences in presentation of mental health issues of migrant youth when compared with dominant culture youth, examining the contributions of culture, context, and the families' own views. Models of care will be described that have tried to elicit a better understanding of the difficulties migrant and refugee children may encounter. Some avenues through which we may expand our current psychiatric models of care will also be addressed. These avenues include the use of interpreters and cultural brokers, addressing the debate around ethnic matching between therapists and patients, promoting a sensitivity to otherness and mediation, and looking at the importance of time issues.  相似文献   
84.
The role of boar seminal plasma proteins attached to the sperm plasma membrane during ejaculation has been studied in saccharide-mediated events in the female reproductive tract. Heparin-binding (Hep(+)) proteins (DQH sperm surface protein, and AQN and AWN spermadhesins) and their aggregated forms (fractions II and III) interacted more strongly with both oviductal epithelium cells and fluid than non-heparin-binding (Hep(-)) proteins (PSP I and PSP II spermadhesins) and their heterodimer (fraction IV), and interactions correlate with affinity of these proteins to yeast mannan. Indirect immunofluorescence (IMF) showed that the AQN 1 spermadhesin and fraction II bind to the apical glycocalyx of the ampulla, as well as the isthmic and uterine tubal junction regions of the oviductal sections. IMF demonstrated the recognition of AQN 1 and fraction II and mannosyl components of oviductal epithelium. We suggest that Hep(+) proteins (especially AQN 1, fraction II) on sperm could enable sperm binding to oviductal epithelium and thus participate in formation of the sperm oviductal reservoir. Interactions of Hep(+) proteins to oviductal epithelium were inhibited by mannan, hyaluronic acid and sialylated O-glycoproteins. No or slight inhibition was observed with sulphated polysaccharides (heparin, chondroitin sulphate) and simple monosaccharides. Besides that, attachment of boar seminal plasma proteins to oviductal epithelium cells was affected by oviductal fluid, the natural environment in the oviduct. Moreover, the ability of hyaluronic acid to inhibit the interaction of sperm surface proteins to the oviduct might play a role in sperm release from the oviductal reservoir and in the capacitation process.  相似文献   
85.
The goal of this study was to evaluate the validity of asthma diagnoses recorded in the Medical Services (physician billing) database of the Canadian province of Quebec. The predictive positive value (PPV) and predictive negative value (PNV) of two operational definitions of asthma based on diagnoses recorded in the database were evaluated. Patients 16-80 years old treated by a respiratory or a family physician in 2002 were selected from the database. The diagnosis derived from the Medical Services database was compared to the diagnosis written in the patient's medical chart. The PPV and PNV of the first operational definition based on one asthma diagnosis or more recorded in the database over a 1-year period were found to be 0.75 and 0.96 for respiratory physicians and 0.67 and 0.99 for family physicians, for patients 16-44 years old. The PPV increased to 0.78 for family physicians and to 0.77 for respiratory physicians when the second operational definition based on two diagnoses of asthma or more was used. Results tended to be lower for 45-80 years old patients. We conclude that diagnoses recorded in the Medical Services database of Quebec are valid to identify patients with asthma.  相似文献   
86.
Protection experiments were conducted using different doses of equine serum butyrylcholinesterase (Eq BuChE) as pretreatment in rats. Cholinesterase activities were determined in blood [whole blood, red blood cells (RBC) acetylcholinesterase (AChE), and plasma BuChE] before and after sarin inhalation exposure in untreated rats and those pretreated with Eq BuChE. Brain AChE activity was also determined in the frontal cortex, basal ganglia and pontomedullar areas following exposure. Dose-dependent increases in plasma BuChE activity and no changes in the RBC and brain AChE activities were demonstrated following i.p. injection of different amounts of Eq BuChE. Decreases in plasma BuChE activity and RBC and brain AChE activities were observed in control rats following sarin inhalation exposure. In rats pretreated with Eq BuChE this inhibition was lower than in control animals. These results demonstrate protective effects of Eq BuChE pretreatment in rats intoxicated with sublethal concentrations of sarin by inhalation.  相似文献   
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88.
PURPOSE: Cancer accounts for 60.9 billion dollars in direct medical costs and 15.5 billion dollars for indirect morbidity costs. These estimates are derived primarily from national surveys or Federal databases. We derive estimates of the costs of cancer using administrative databases, which include claims and employment-related information on individuals insured by private or Medicare supplemental health plans. METHODS: A retrospective matched-cohort control analysis was performed using 1998 to 2000 databases with information on insurance claims, benefits, and health productivity for 3 million privately insured employees, their dependents, and early retirees. Study patients had new diagnoses of one of seven types of cancer (n = 12,709). Controls without cancer were matched at a 3:1 ratio by demographics. A variable follow-up length was used (maximum of 2 years). Direct costs included health care costs for patients and deductibles and copayments for caregivers. Indirect costs of work absence and short-term disability (STD) were calculated for a subgroup of cancer patients and caregivers. RESULTS: Mean monthly health care costs ranged from 2,187 dollars for prostate cancer to 7,616 dollars for pancreatic cancer, most often driven by hospitalization. Costs for controls were 329 dollars per month. Indirect morbidity costs to employees with cancer averaged 945 dollars, a result of a mean monthly loss of 2.0 workdays and 5.0 STD days. CONCLUSION: The economic burden of cancer is substantial. It is feasible to derive tumor-specific estimates of direct and indirect costs for large numbers of cancer patients using administrative databases. Policy makers charged with providing annual cost-of-cancer estimates should incorporate data obtained from a broad range of sources.  相似文献   
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