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11.
HEREDITARY DISEASE: Hereditary anomalies of homocysteine metabolism are quite uncommon and manifest by very high homocysteine levels (> 100 mumol/l) and associated homocysteinuria. The risk of premature cardiovascular disease is high. Clinical, biological and epidemiological data accumulated since the 70 s have demonstrated that a moderately elevated serum homocysteine level favors the development of atherothrombosis. PROVEN RISK: The risk of coronary or cerebral events is 1.5 to 3-fold higher for fasting homocysteine levels above 15 mumol/l. These data show that moderately elevated homocysteine level is a powerful cardiovascular risk factor. Further information is however needed to ascertain its frequency in the population and determine whether it is a truly independent risk factor. THERAPEUTIC OPTIONS: Most cases of moderately elevated homocysteine can probably be explained by gene-environment interactions. Homocysteine levels can be lowered by oral administration of vitamin cofactors implicated in homocystein metabolisms: folic acid, vitamin B6, vitamin B12.  相似文献   
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The insulin-like growth factor (IGF) axis may play opposing roles in health and disease.The age-related declines in growth hormone and IGF-I may be associated with potentially deleterious changes in body composition and functioning, but recent studies suggest that IGF-I levels may be related to risk of prostate, colorectal, premenopausal breast, and possibly other cancers. Thus, we studied dietary influences on plasma IGF-I and IGF-I:IGF-binding protein-3 ratio in 753 men in the Health Professionals Follow-Up Study who completed a food frequency questionnaire. In this generally well-nourished population of middle-aged to elderly men, plasma IGF-I and IGF-I:IGF-binding protein-3 molar ratio tended to increase with higher intake of protein and minerals, including potassium, zinc, magnesium, calcium, and phosphorus. Men with relatively high intakes of total protein (top quintile) and minerals (top quintile of the five minerals combined) had a 25% higher mean plasma level of IGF-I compared with those in the low quintiles simultaneously. The major sources of animal protein, including milk, fish, and poultry, but not red meat, as well as total vegetable protein, were associated with an increase in IGF-I levels. Energy intake was positively related to plasma IGF-I level but only in men with body mass index <25 kg/m(2). The age-related decline in plasma IGF-I may be exacerbated by low intakes of protein and minerals. The potential role of these dietary factors on cancer risk through altering IGF-I levels requires study.  相似文献   
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BACKGROUND: Congenital mediastinal teratomas are rare and may present with nonimmune hydrops. The lesion may be misinterpreted on ultrasound. CASES: A 21-year-old woman, gravida 2, para 0111, was evaluated at 19 4/7 weeks of gestation for suspected fetal death. An ultrasonogram confirmed the death and revealed a posterior encephalocele and possible herniated liver in the chest. At autopsy a 5.2 x 7.5 x 1.0-cm mediastinal teratoma completely compressed the chest organs. No encephalocele was present. A 15-year-old woman, gravida 1, para 0, underwent an ultrasonogram at 27 weeks when fetal heart rate decelerations were detected. The ultrasound revealed hydrops and suggested a calcified left cardiac ventricular wall and diaphragmatic hernia. Autopsy of the stillborn female showed an 8.0 x 6.0 x 4.0-cm teratoma in the mediastinum, with small heart and lungs. A 23 2/7 weeks stillborn female was delivered to a 32-year-old woman, gravida 5, para 2, and noted to be hydropic. Ultrasound had suggested multiple anomalies and hydrops. Autopsy revealed a 23 g, 4.5 x 3.0 x 3.0-cm teratoma that filled the anterior mediastinum. CONCLUSION: Congenital mediastinal teratoma may be associated with fetal death. It is within the differential diagnosis of nonimmune hydrops, particularly if a thoracic mass is detected on ultrasonography.  相似文献   
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This paper reports the findings of a phenomenological study which explored the lived experience of the nurse practitioner (NP) who had been educated through a problem-based learning (PBL) approach and the meaning of that education on the NPs current clinical practice. This was accomplished through the use of in-depth interviews to gather information from 13 practicing NPs. It was found that information obtained in the PBL classroom could be directly applied to professional practice providing the NP with the skills needed for clinical decision making with a holistic viewpoint and satisfaction in clinical practice. The analysis both supports and challenges the current research on perceptions, experiences, satisfaction, and outcomes related to PBL.  相似文献   
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OBJECTIVES: To compare the association between subjective ladder ranking and health measures with the association between objective indices and health measures in older Taiwanese men and women. DESIGN: Cross-sectional study. SETTING: A population-representative sample of elderly and nearly elderly men and women in Taiwan. PARTICIPANTS: The study included 991 participants from the Social Environment and Biomarkers of Aging Study in Taiwan. MEASUREMENTS: The information collected included demographic characteristics; subjective ladder score of SES; objective measures of SES, including education, income, and occupation; health behaviors; health-related variables such as self-rated health, basic activity of daily living difficulties, instrumental activity of daily living (IADL) difficulties, and physical activity difficulties; and depression score. RESULTS: Low ladder score was associated with poorer self-rated health and more reported IADL and physical activity difficulties, even after adjustment for objective measures of SES and other covariates. The multiply adjusted odds ratio for a one-quartile difference in ladder score and worse self-rated health was 1.19 (95% confidence interval=1.06-1.33). The associations between subjective ladder ranking and health status were generally stronger in those who had 6 years or less of education than in those who received more education. CONCLUSION: A simple subjective assessment of one's ranking on the social hierarchy was associated with self-rated health and physical functional status in an older ethnic Chinese population. The associations were independent of the effects of traditional objective measures of SES, such as education, income, and occupation.  相似文献   
17.
An increased consumption of energy-dense, nutrient-poor food and beverages as a result of a changing obesogenic environment contributes substantially to the increasing prevalence of childhood overweight and obesity. This paper reviews the nature and extent of food industry influences which expose children to commercial influences and thus might affect unhealthy dietary behaviour and finally contributes to obesity. A systematic search of nine electronic databases (including PubMed, PsycINFO, EconLit) and reference lists of original studies and reviews using key search terms identified 1900 articles. Of these only thirty-six articles met the inclusion and quality criteria. A narrative synthesis of the reviewed studies revealed six key obesogenic environments by which the food industry possibly influences obesity-related dietary behaviours in young children. These were schools, retailers, mass media “television”, mass media “internet”, home and promotional campaigns. Identifying these obesogenic environments is critical for monitoring and controlling the food industry, the development of effective environmental-level interventions to prevent childhood overweight and obesity and to identify knowledge gaps to be addressed in future research to support informed decisions of policy makers.  相似文献   
18.
Metabolic Brain Disease - Thymoquinone (Tq), an active compound of Nigella sativa, has been known for its anti-inflammatory, antioxidant, and neuroprotective characteristics. The present study is...  相似文献   
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Registries and cord blood banks around the world collect and store the HLA types of volunteers in order to identify matched unrelated donors for patients requiring hematopoietic stem cell transplantation. This task is complicated by the many formats in which HLA types are provided by the testing laboratories (types obtained by serology vs by DNA-based methods; high vs intermediate vs low resolution) and by the need to identify which of these diverse types are most likely to match the HLA assignments of a searching patient as closely as possible. Conversion of the assignments to 'search determinants' may be included within the algorithm used to select and prioritize a list of potentially suitable donors, either as an aid to matching or as a tool to optimize the performance of comparisons within large data files. The strategies used by registries to create search determinants are described. A set of search determinants, utilized by the National Marrow Donor Program, is provided as an example and is intended to initiate further discussion aimed at understanding the process used by each registry with the possibility of developing a standard process among registries worldwide.  相似文献   
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