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101.

Purpose  

To study the utility of a training session offered to junior embryologists, comparing the results obtained with those reported by a group of senior embryologists.  相似文献   
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BACKGROUND: Infants with multiple malformations are important in birth defect epidemiology and malformation monitoring because human teratogens have often caused complex malformations. Various methods for the analysis of multimalformed infants have been tried. METHOD: By using data from four large registries of congenital malformations, 5256 infants were identified with two or more among 73 selected malformations. Pairwise associations between malformations were detected by multiple logistic regression analyses, and putative confounders (programme, maternal age, autopsy, etc.) were controlled for. For each significant pairwise association, further analyses were performed in order to find associations with a possible third malformation. RESULTS: The importance of controlling for several confounders was demonstrated. Several well-known associations were found, which supports the technique used. The interpretation of three-way associations was discussed. Results from the present study were compared with those obtained using some other methods. CONCLUSIONS: Different confounders can cause biased associations. The method presented in the paper takes this into consideration and is therefore more likely than previously used techniques to give unbiased information on the clustering of different malformations among multimalformed infants.  相似文献   
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The distribution of anticonvulsant drug therapy was studied in 318 malformed infants with known histories of maternal epilepsy. Data on the infants was collected from six birth defect monitoring programs in Europe and South America.Use of specific types of anticonvulsants varies midely among reporting countries. Heterogeneity of drug-malformation distribution, was analyzed to determine whether use of specific drugs were linked to specific malformations. A significant association was seen between maternal use of valproic acid and spina bifida, and a weaker, non-significant one between carbamazepine and spina bifida. Facial clefts were associated with both diphenylhydantoin and phenobarbitone use and also with polytherapy. These differences indicate that the actual drug used is significant for the teratogenic process. The technique may be useful in analyses of other drug-related teratogenic questions.  相似文献   
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麻黄碱在受热时可挥发,在蒸除提取溶剂时相随挥发损失,不能用常规的提取重量法测定。使用本室新近研制的涂圈压电传感器作为超微量质量敏感元件,取常规提取重量法的基本原理,并加以改进,可以实现麻黄碱的快速分析,从而扩大该经典方法的应用范围。本法可测定低至亚μg级的麻黄碱,具有方法简便、灵敏度高等优点。  相似文献   
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There are several studies that have found a positive association between neural tube defects (NTDs) and the common mutation 677C > T of 5,10-methylenetetrahydrofolate reductase (MTHFR), and others that have not found such an association. We updated the meta-analyses of the published data about NTDs and MTHFR 677C > T variant from January 1994 to October 2005 identifying 170 potentially relevant studies. After applying pertinent exclusion criteria, 37 different populations from 32 studies were included in the meta-analysis, with a total of 3,530 cases and 6,296 controls. Further we stratified the data according to geographical region and ethnicity, and produced two separated meta-analyses for non-Latin European and Latin European descent populations. The general (odds ratio 1.41; 95% confidence interval 1.24-1.59), and the non-Latin European meta-analyses (1.62; 1.38-1.90) indicate an association of TT genotype and NTDs; no association was demonstrated for Latin European populations (1.16; 0.95-1.43). The examination of non-Latin European studies revealed that the association of TT genotype with NTD has only been proven for Irish populations, both by case-control studies, and by family-based tests, such as the allele transmission disequilibrium test (TDT).  相似文献   
110.
BACKGROUND: Navarra has an information system of HIV diagnoses working since the beginning of the epidemic up to the present day. This study aims at describing and evaluating this system, focusing on its sensitivity. METHODS: The updated guidelines for evaluating public health surveillance systems from the CDC were used to describe the purpose and operation of the system and to analyse its attributes for the period 1985-2003. For the evaluation of the sensitivity the regional database of antiretrovirals distribution was used. RESULTS: The HIV surveillance system of Navarra is confidential and name-based, and includes all HIV-infection cases diagnosed each year. The information sources of the system are: (a) all the laboratories in the public health system that perform the western blot test, and (b) hospital discharge registries. The system covers the entire population of Navarre (584,734 inhabitants). It uses the HIV case definition proposed by the European Centre for the Epidemiological Monitoring of AIDS. The system is well-accepted by the community and by all the stakeholders, including those providing data. By the end of 2003 it included 2302 HIV cases, and 98.8% of all patients who had ever received antiretrovirals in Navarra. CONCLUSIONS: The HIV information system of Navarra is simple, useful, well-accepted and highly sensitive. The information about antiretroviral distribution was useful for this evaluation.  相似文献   
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