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51.
In all countries, the priority for reducing road traffic injuries should be prevention. Nonetheless, there are low-cost ways to strengthen the care of injured persons, that will help to lower the toll from road traffic. The purpose of this review was to elucidate ways to accomplish this goal in the context of less developed countries. Studies selected for this review were obtained by Medline review, selecting on key words such as trauma, injury, trauma care, essential health services, and developing country. Articles pertaining to any country and all available years were considered. In addition, the authors utilized articles from the gray literature and journals from Mexico and Ghana that are not Medline referenced. Studies surveyed point to road safety and other forms of injury prevention, as well as prehospital care, as likely priorities for developing countries. Nonetheless, hospital-based improvements can contribute to decreases in mortality and, especially, decreases in disability. For both prehospital and hospital based care, studies revealed several critical weak points to address in: (1) human resources (staffing and training); (2) physical resources (equipment, supplies, and infrastructure); and (3) administration and organization. The 'essential services' approach, which has contributed to progress in a variety of fields of international health, needs to be developed for the care of the injured. This would define the trauma treatment services that could realistically be made available to virtually every injured person. It would then address the inputs of human resources, physical resources, and administration necessary to assure these services optimally in the different geographic and socioeconomic environments worldwide. Finally, it would identify and target deficiencies in these inputs that need to be strengthened.  相似文献   
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Transmural myocardial infarction in dogs produces denervation of sympathetic nerves in viable myocardium apical to the infarct that may be arrhythmogenic. It is unknown whether sympathetic denervation occurs in humans. The purpose of this study was to use iodine-123-metaiodobenzylguanidine (MIBG), a radiolabeled guanethidine analog that is actively taken up by sympathetic nerve terminals, to image noninvasively the cardiac sympathetic nerves in patients with and without ventricular arrhythmias after myocardial infarction. Results showed that 10 of 12 patients with spontaneous ventricular tachyarrhythmias after myocardial infarction exhibited regions of thallium-201 uptake indicating viable perfused myocardium, with no MIBG uptake. Such a finding is consistent with sympathetic denervation. One patient had frequent episodes of nonsustained ventricular tachycardia induced at exercise testing that was eliminated by beta-adrenoceptor blockade. Eleven of the 12 patients had ventricular tachycardia induced at electrophysiologic study and metoprolol never prevented induction. Sympathetic denervation was also detected in two of seven postinfarction patients without ventricular arrhythmias. Normal control subjects had no regions lacking MIBG uptake. This study provides evidence that regional sympathetic denervation occurs in humans after myocardial infarction and can be detected noninvasively by comparing MIBG and thallium-201 images. Although the presence of sympathetic denervation may be related to the onset of spontaneous ventricular tachyarrhythmias in some patients, it does not appear to be related to sustained ventricular tachycardia induced at electrophysiologic study.  相似文献   
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This analysis of data from the Household Injury Survey conducted in Viet Nam in 2004-2005 sought to characterize the patterns of work-related injuries in Viet Nam and to determine whether self-employed and artisanal workers had higher rates of injuries than formally employed workers. The annual incidence rate of work-related injuries in Viet Nam was 7.06 per 1,000 person-years. Daily alcohol consumption was strongly associated with work-related injuries. The highest burden of injuries was among farmers. Mechanical forces were the most common mechanism of injury. Self-employed workers had a rate of work-related injuries 26% higher than that of formally employed workers. Self-employed workers were younger, less educated, and more likely to be male. This population-based survey showed substantial underreporting of occupational injuries by existing surveillance mechanisms, which focus on formally employed workers. Priorities for future work include developing an integrated surveillance system for injuries and implementing further needs assessments to improve the prevention of occupational injuries.  相似文献   
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Gamma-glutamyl transpeptidase (GGT) activity has been shown to increase in preneoplastic cells in various experimental carcinogenesis models and in some human tumors. This pilot study was undertaken to examine its potential use in detection of sites of human oral carcinogenesis. Samples were taken from 16 surgical specimens: 12 resection specimens for squamous carcinomas and 4 benign mucosal lesions. Twelve of the patients were tobacco users. Diffuse GGT activity was found in all tobacco users and heavy cellular activity in all carcinomas. In four of the carcinoma-resection specimens, occasional cells staining heavily for GGT activity were noted in epithelium distant from the tumor itself. These results are discussed in relation to the potential value of GGT activity as a marker from preneoplastic changes in oral epithelium.  相似文献   
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Sexual, reproductive and contraceptive risk factors were investigated in a matched community-based case-control study of carcinoma-in-situ of the uterine cervix in Sydney. The risk was related strongly to the number of sexual partners: women who had had seven or more sexual partners in a lifetime had a six-fold increased risk compared with those with one or no partner. Early age at first sexual intercourse was also a risk factor, but this effect was reduced substantially after adjustment for the number of partners, with only a two-fold excess risk persisting for those with first intercourse before the age of 16 years as compared with those whose first sexual intercourse was at the age of 25 years or later. The long-term use of oral contraceptive agents was associated with an elevated risk (relative risk, 2.3 for more than six years of use); this effect was maintained for both oestrogen and progestogen doses. The risk increased with the number of induced abortions that had been undergone (relative risk, 2.2 for two or more abortions), but this effect was not statistically significant. A protective effect was found for women who had had a tubal ligation, for those who practised the rhythm method of birth control, and for women who breastfed. It is possible that these reduced risks may relate to unmeasured variables of life-style.  相似文献   
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Three cell lines were isolated from a patient with osteosarcoma of the femur. These lines were obtained from the primary neoplasm before (HTLA145) and after (HTLA161) chemotherapy and from a metastasis of the lung (HTLA195) in the same patient. The three cell lines exhibited a similar morphology in culture and formed tumors in nude mice which demonstrated a histopathology similar to that which had been observed in the patient. High expression of the genes coding for the alpha-1 and alpha-2 chain of collagen Type I was found in vitro and in s.c. tumors growing in nude mice. The c-myc protooncogene was amplified in all three cell lines and extensive expression of c-myc was found in vitro and in vivo. No heterogeneity in regard to c-myc expression in vivo was detected by in situ localization in tumors growing in nude mice.  相似文献   
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