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The Munich Community Health Service (Medical School-Service Department) conducted an alcohol prevention project in ten public secondary schools. The 423 pupils (11-17 years of age) filled in a questionnaire on alcohol and discussed it afterwards under the guidance of a school physician and a teacher using guideline information. The results of the survey are presented in this paper. Additionally, suggestions for transferring the results to conceptualize and carry out preventive measures are made. The results indicate that the first experience with alcohol occurred early in life. One-fifth of the sample had already tried alcohol at the age of six. Immediate effects of alcohol (e.g. state of drunkenness) were experienced by 35.7 percent of the sample group. Kiosks, shops, and beverage stores were named most frequently as sources for alcohol. The sources of social support varied with respect to sex and age. With increasing age of the children, parents were contacted less frequently whereas the role of peers increased. The present results supply possible paths of action for the development of successful prevention strategies, e.g. by pointing out the early age of onset as well as specific sources of alcohol acquisition.  相似文献   
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Few studies have documented public perceptions of environmental health risks from exposure to overhead transmission lines. In particular, little information has been provided on the impact of worry on symptom prevalence in residents living adjacent to high voltage transmission lines. The current study assessed symptom prevalence and worry in 152 Orange County female residents living either adjacent to overhead transmission lines or one block away. Forty-five percent of the respondents were either very worried or somewhat worried about the transmission lines and 55% were slightly worried or not worried at all. Results indicated that for those who did not live on the easement level of worry did not affect the prevalence of health problems. For those who lived on the easement, the most worried respondents were more likely to report health problems. Disclosure of health problems may depend more on individuals' level of worry about rather than proximity to overhead transmission lines. Possible limitations of this study include personality variables such as hypochondriasis which were not assessed, recall bias, and social desirability. The homogeneity of subjects may also limit the generalizability of findings.  相似文献   
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The formation of factor VIII antibodies is a major problem for replacement therapy of haemophilia A patients. Antibodies occur in 5-30% of patients with severe haemophilia A. The reason for antibody formation is still unknown. In this study we correlate for the first time different factor VIII gene mutations, stop- and missense mutations, large and small deletions and intrachromosomal intron 22 recombinations to antibody formation. A total of 364 patients with known inhibitor status of our institute, of the database, and of 3 studies representing intron-22-inversion data are included. The results show that the risk for developing factor VIII antibodies is strongly related to stop mutations. large deletions and intrachromosomal recombinations. A probable explanation could be the complete lack of endogenous circulating factor VIII protein in these cases. Other factors that might be important for the pathogenesis of inhibitor formation, e. g. the antenatal period, as well as possible therapeutic effects, are discussed.  相似文献   
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If technologies for decentralised sanitation and reuse (DESAR) and for natural stormwater management should at least partially replace existing systems, then intensive reconstruction work becomes essential. A conversion can only be realised successively over a long period due to high construction and financial expenses and requires new strategies. This paper presents the development and practical implementation of a mathematical tool to find an optimised strategy for the realisation of alternative and more decentralised drainage and sanitation concepts in existing urban areas. The succession of construction measures (e.g. the implementation of decentralised greywater recycling) for the whole period of consideration is determined based upon a mathematical optimisation model on the condition that the favoured future state is known. The model describes the complex interdependencies of the urban water and nutrient cycle and enables the minimisation of both financial efforts and ecological impacts on the way toward the future state. The results of the implementation for a rural area in Germany show that the mathematical optimisation is an adequate instrument to support decision-making processes in finding strategies for the realisation of sustainable urban water management.  相似文献   
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We solve the Kohn-Sham equations self-consistently in the local density approximation for spheroidal sodium clusters in the particle range 8 ≤ Z ≤ 40. We use a smooth fermi-like jellium density to simulate the influence of the ions in the surface region and obtain similar results as Ekardt and Penzar, but slightly different regions of prolate-to-oblate transitions. We present the systematics of potential energy curves with respect to transitions between oblate, prolate and spherical shapes. Shape transitions occur at particle numbers 12/14 (prolate/oblate), 18/20/22 (oblate/spherical/prolate) and 30/32 (prolate/oblate), which are in good agreement with experimental results. The quadrupole and hexadecupole overlap of the electron density with the jellium is investigated, showing a strong hexadecupole dependence for selected clusters. Collective dipole resonances are described in a simple sum rule approach, which reveals a double splitting according to the different resonance frequencies along the principal axes of the spheroid. The systematics of the resonance peaks for the larger clusters with Z ≥ 20 is in good agreement with experimental results.  相似文献   
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The erucic acid content of broccoli florets, sprouts, and seeds was found to be about 0.8, 320, and 12100 mg/100 g, respectively. Using the erucic acid limit established for canola oil in the U.S.A. and Canada as a guideline, the estimated dietary intake of erucic acid from florets and sprouts was considered of little consequence, whereas in seeds a relatively small amount (about 35 g/wk) equaled our calculated exposure limit for erucic acid. Additionally, the most complete fatty acid distribution yet published for the various forms of broccoli are presented.  相似文献   
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