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991.
Microarrays provide a versatile platform for utilizing information from the Human Genome Project to benefit human health. This article reviews the ways in which microarray technology may be used in breast cancer research. Its diverse applications include monitoring chromosome gains and losses, tumour classification, drug discovery and development, DNA resequencing, mutation detection and investigating the mechanism of tumour development.  相似文献   
992.
OBJECTIVE: To investigate the relationship between iron status in infancy and type of milk and weaning solids consumed. DESIGN: An observational cohort study. SETTING: 928 term infants from the Avon Longitudinal Study of Parents and Children in 1993-94. METHODS: Haemoglobin and ferritin concentrations at 8 and 12 months were assessed in relation to type and quantity of milk intake at 8 months. RESULTS: By WHO criteria, 22.7% of the infants were anaemic at 8 months and 18.1% at 12 months. More breast--than formula-fed infants were anaemic at 8 and 12 months. Cows' milk as the main drink was associated with increased anaemia at 12 months and low ferritin at 8 and 12 months. No association was found between any nutrients and haemoglobin concentrations. Protein and non-haem iron intakes were positively associated with ferritin concentrations and calcium intake negatively. This effect was more marked in infants being fed cows' milk. More than 25% of infants in the breast milk and cows' milk groups and 41% of infants having >6 breast feeds per day had iron intakes below the lower reference nutrient intake. Feeding cows' milk or formula above 600 ml or >6 breast feeds per day was associated with lower intakes of solids. CONCLUSIONS: Both breast and cows' milk feeding were associated with higher levels of anaemia. Satisfactory iron intake from solids in later infancy is more likely if formula intake is <600 ml per day and breast feeds are limited to <6 feeds per day. Cows' milk should be strongly discouraged as a main drink before 12 months.  相似文献   
993.
OBJECTIVE: To determine the cost effectiveness of a public health legislative/educational strategy to reduce tap water scalds in children less than 10 years of age. DESIGN: Cost-effectiveness analysis conducted from the government perspective over a 10-year time horizon. POPULATION: Children under 10 years of age in Ontario, Canada INTERVENTIONS: Legislation to set thermostat settings on new domestic water heaters to lower temperatures (maximum 49 degrees C) plus annual educational notices to utility customers versus status quo. MAIN OUTCOME MEASURES: The burden of tap water scalds, healthcare resource utilization, the cost and effectiveness of the proposed intervention, and the probabilities assigned to health outcomes were modeled in a decision analysis based on population-based data, patient charts, and the published medical literature. All costs and health outcomes beyond 1 year were discounted at 3%. RESULTS: An estimated 182 children under 10 require medical care for tap water scald injuries annually in Ontario (13.98 per 100,000). Of these, 65 require emergency department (ED) care only (median cost $C149 per injury), 103 require ED care with clinic follow-up ($C577 per injury), 14 require hospital admission ($C5203 per injury), and two require surgical skin grafting ($C28,526 per injury). The estimated cost of the intervention was $C51,000 annually, with a projected 56% reduction in tap water scald injuries. Over 10 years, the intervention group would show total costs of $C1.17 million and 704 scalds, compared with $C1.65 million and 1599 scalds in the status quo group. Therefore, the intervention would be cost saving, with an incremental ratio of $C531 saved per scald averted. Sensitivity analyses showed that the intervention would remain cost saving through a wide range of variable estimates. CONCLUSIONS: Legislation to lower thermostat settings on domestic water heaters plus annual educational notices to utility customers would generate cost savings while reducing the morbidity from tap water scalds in children.  相似文献   
994.
卢杰 《英国医学杂志》2007,10(5):266-267
近期的BMJ中,一位囊性纤维化病人讲述了自己伴随疾病从儿童到成人的经历(见本期第309页)。在很多的艰难险阻当中,她提到了从儿童期到成人期治疗的过渡是一条“崎岖之路”。她说当16岁时,她宁愿倾家荡产进入一家过渡诊所,也不愿意直接去另一家医院的成人诊所。[第一段]  相似文献   
995.
Kawasaki disease is a syndrome that usually occurs in infants and children. It is characterized by an exanthem, enanthem, fever, lymphadenopathy, and polyarteritis of variable severity. The present report describes cases in which an initial presentation of Kawasaki disease included abdominal and gastrointestinal symptomatology.  相似文献   
996.
997.
Striatal lesions disrupt both motor and cognitive performance in rats, many aspects of which can be restored by striatal transplants. Because the normal striatum is involved in the formation and maintenance of motor habits, it has been hypothesized that grafted animals may require explicit retraining to relearn previously established habits that have been disrupted by the lesions. We have used a lateralized-discrimination task to reproduce this "learning to use the transplant" effect, combined with a transfer-of-training paradigm to demonstrate that recovery requires relearning specific lateralized stimulus-response associations and cannot be explained simply by a generalized training-dependent improvement in motor skill. These results have clear implications for developing appropriate strategies for the rehabilitation of Huntington's disease patients participating in clinical transplantation programs.  相似文献   
998.
This article reports a large-scale study of the prediction of marijuana use cessation among adolescents who were regular users at baseline. Social, attitude, intrapersonal, violence-related, drug-use-related, and demographic baseline measures served as predictors of whether or not 566 current marijuana users reported having quit use 1 year later. Quitting was defined as having not used marijuana in the last 30 days and having no intention to use marijuana in the future (31% of the baseline users). Those who were slightly older, who reported receiving relatively less approval for using drugs, who held relatively unfavorable attitudes about the acceptability of drug use, and who reported relatively less victimization in the last year were relatively likely to quit. Implications of these results include the need to increase unacceptability of marijuana use to help increase efforts at self-initiated quitting.  相似文献   
999.
This paper reports the association of current stimulant use with demographic, other substance use, violence-related, social and intrapersonal variables among a large sample of high risk adolescents. A total of 21.4% of the sample reported using stimulants in the last 30 days. In a final, multivariable model, nonredundant concurrent predictors of current stimulant use were reports that friends use stimulants, reports that stimulants were likely to be used again in the next 12 months, use of alcohol, hallucinogens, or cocaine in the last 30 days, use of alcohol or other drugs to feel more safe, and reports of depression in the last week. Being above the median on 0 to all 7 of these correlates predicted from 0% to 85% of those who were above the median on current stimulant use. One may speculate that programming for these stimulant-using youth should include treatment of multiple substances, depression, and correction of social-cognitive misperceptions.  相似文献   
1000.
This study investigated the modulation of type I collagen gene expression in normal fibroblasts by breast tumour cells. Northern analysis of total RNA extracted from stages I, II and III breast tumour tissue revealed that collagen mRNA levels were elevated in stage I tumours compared to the adjacent normal breast tissues, whereas they were decreased in stages II and III breast tumours. This aberrant collagen gene expression was confirmed by non-radioactive RNA:RNA in situ hybridization analysis of 30 breast carcinomas which localized the production of type I collagen mRNA to the stromal fibroblasts within the vicinity of the tumour cells. In order to determine whether the tumour cells were directly responsible for this altered collagen production by the adjacent fibroblasts, breast tumour cell lines were co-cultured with normal fibroblasts for in vitro assessment of collagen and steady-state collagen RNA levels. Co-culture of tumour cells and normal fibroblasts in the same dish resulted in down-regulation of collagen mRNA and protein. Treatment of the fibroblasts with tumour-cell conditioned medium also resulted in decreased collagen protein levels but the mRNA levels, however, remained unaltered. These results suggested that the tumour cells either secrete a labile 'factor', or express a cell surface protein requiring direct contact with the fibroblasts, resulting in down-regulation of collagen gene expression. Modulation of the ECM is a common characteristic of invading tumour cells and usually involves increased production of collagenases by the tumour cells or stromal fibroblasts. This study showed that tumour cells were also able to modulate collagen mRNA production by stromal fibroblasts, which may facilitate tumour cell invasion and metastasis.  相似文献   
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