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STUDY OBJECTIVE: The aim was to study the spectrum of clinical problems and outcomes in infants born at an urban academic hospital. In consequence, as part of the overall study, the incidence of congenital anomalies and the outcomes of affected infants were recorded. DESIGN: This was a prospective, hospital-based study, undertaken on liveborn infants born over a 3-year period, 1 May 1986 to 30 April 1989. SETTING: Kalafong Hospital, Pretoria. MAIN RESULTS: A total of 17,351 liveborn infants was examined and the total congenital anomalies incidence was 11.87 per 1,000 livebirths. The central nervous system was the system most frequently involved (2.30 per 1,000 livebirths), followed by the musculoskeletal system (2.13 per 1,000 livebirths). The commonest individual congenital anomaly was Down syndrome (1.33 per 1,000 livebirths), followed by neural tube defects (0.99 per 1,000 livebirths) and ventricular septal defects (0.69 per 1,000 livebirths). In 11% (2.25 per 1,000 livebirths) of neonatal deaths, infant loss was attributable to congenital anomalies. CONCLUSIONS: The incidence of congenital anomalies in black South African neonates, born in an urban setting, is as high as in other First- and Third-World countries, and the incidence of some individual congenital anomalies is higher. This study indicates the need for further research and the establishment of prenatal, genetics and paediatric facilities to manage these problems.  相似文献   
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Glutamate receptors can be divided in several groups with distinct functional properties. An additional level of complexity has emerged from recent high resolution immunogold analyses which have provided evidence for a differential targeting of glutamate receptors to specific subsynaptic membrane domains. Notably, different types of glutamate receptor may differ in their distance to the release site and in their spatial relation to glutamate transporters. These data imply that the subsynaptic expression of a given glutamate receptor may bias its response to a released quantum of transmitter and suggest that receptor targeting may be implicated in the modulation of glutamatergic neurotransmission.  相似文献   
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BACKGROUND: Oxidized low-density lipoprotein is involved in the pathogenesis of atherosclerosis. In epidemiological studies antioxidants have been inversely related with coronary heart disease. Findings from controlled trials are inconclusive. METHODS: We studied the primary preventive effect of vitamin E (alpha tocopherol) and beta carotene supplementation on major coronary events in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study, a controlled trial undertaken primarily to examine the effects of these agents on cancer. A total of 27 271 Finnish male smokers aged 50 to 69 years with no history of myocardial infarction were randomly assigned to receive vitamin E (50 mg), beta carotene (20 mg), both agents, or placebo daily for 5 to 8 years (median, 6.1 years). The end point was the first major coronary event, either nonfatal myocardial infarction (surviving at least 28 days; n = 1204) or fatal coronary heart disease (n = 907). RESULTS: The incidence of primary major coronary events decreased 4% (95% confidence interval, -12% to 4%) among recipients of vitamin E and increased 1% (95% confidence interval, -7% to 10%) among recipients of beta carotene compared with the respective nonrecipients. Neither agent affected the incidence of nonfatal myocardial infarction. Supplementation with vitamin E decreased the incidence of fatal coronary heart disease by 8% (95% confidence interval, -19% to 5%), but beta carotene had no effect on this end point. CONCLUSIONS: Supplementation with a small dose of vitamin E has only marginal effect on the incidence of fatal coronary heart disease in male smokers with no history of myocardial infarction, but no influence on nonfatal myocardial infarction. Supplementation with beta carotene has no primary preventive effect on major coronary events.  相似文献   
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MT-PVLT-10 transgenic mice express the large T-antigen of polyomavirus under the control of the mouse metallothionein-1 promoter. The males of this transgenic line developed testicular tumor and seminal vesicle engorgement at advanced ages. A novel partial cDNA was identified which hybridized to a 2.6 kilobase mRNA. The expression of this mRNA increased approximately two- to fifteen-fold in immortalized cell lines derived from testicular tumors as compared to similar cell lines derived from pre-adenomatous testes. The in vivo pattern of expression for this cDNA as well as its expression in various primary cultures and established cell lines derived from testis of MT-PVLT-10 mice is presented. Overlapping cDNA clones from liver, testes, and brain cDNA libraries containing the entire coding region for this novel cDNA have been isolated and sequenced. The coding region of this gene comprises 1179 nucleotides and predicts a polypeptide of 393 amino acids (calculated molecular mass 44,318). Motif analysis of the amino acid sequence has revealed that it contains several hydrophobic alpha-helices characteristic of transmembrane proteins.  相似文献   
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The paper gives data on the composition and strength characteristics and experimental and clinical findings of resolving antimicrobial suture materials, such as Capromed-type one, based on the modified caproic fiber coated by the biocompatible polymer PPB-1 which contains antimicrobial drugs. Capromed threads are demonstrated to have high strength characteristics and resolve in the body within 8-9 months. Coating the modified caproic fibers with the biocompatible copolymer imparts them pseudomonfilament characteristics and prevents the penetration of cellular elements to the thickness of threads. The content of antibacterial agents in the polymer coating confers prolonged antibacterial properties on Capromed. Desorption of antimicrobial agents from Capromed is conducive to more favourable healing, prevents the development of ligature fistulas, favours an over 4-fold reduction in the incidence of wound complications, as compared to the controls.  相似文献   
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Hair follicle afferent boutons in the spinal dorsal horn of the cat were examined for L-glutamate enrichment. Two hair follicle afferent axons were labelled intra-axonally with horseradish peroxidase, and post-embedding immunogold reactions of L-glutamate were performed on thin sections containing horseradish peroxidase-labelled boutons. Quantitative analysis showed that hair follicle boutons were associated with immunogold reactions for L-glutamate which were almost twice as dense as average values for dorsal horn tissue. Further analysis revealed that hair afferent boutons displayed 2.3-times the average gold particle density associated with post-synaptic dendrites and 3-times the average immunogold density for L-glutamate of structures which were known to be immunoreactive for GABA. This enrichment of L-glutamate in identified hair afferent terminals supports the idea that the amino acid is a neurotransmitter of hair follicle primary afferent axons.  相似文献   
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