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991.
The data requirements of a large multidisciplinary tuberculosis case contact study are complex. We describe an ACCESS-based relational database system that meets our rigorous requirements for data entry and validation, while being user-friendly, flexible, exportable, and easy to install on a network or stand alone system. This includes the development of a double data entry package for epidemiology and laboratory data, semi-automated entry of ELISPOT data directly from the plate reader, and a suite of new programmes for the manipulation and integration of flow cytometry data. The double entered epidemiology and immunology databases are combined into a separate database, providing a near-real-time analysis of immuno-epidemiological data, allowing important trends to be identified early and major decisions about the study to be made and acted on. This dynamic data management model is portable and can easily be applied to other studies.  相似文献   
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OBJECTIVE: To examine the association between birth weight and body fat distribution in a group of adolescent girls. DESIGN: A total of 216 white girls who were born in Southampton had their heights, weights, waist and hip circumferences, and skinfold thicknesses measured when they were aged between 14 and 16 years. RESULTS: The girls who were smallest at birth, but who were fattest at time of measurement were the most centrally obese. In girls whose body mass index was above the median (21 kg/m2), the subscapular to triceps skinfold ratio rose by 9% for every kilogram decrease in birth weight. Among overweight girls, with a body mass index over 25, the ratio rose by 27% for every kilogram decrease in birth weight. CONCLUSION: In adolescent girls, the tendency to store fat on the trunk rather than the limbs, seems to be programmed by growth in fetal life, and is most evident in those who are overweight.  相似文献   
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从绵毛马兜铃(AristolochamannissimaHance)中分得一个马兜铃酸倍半萜的酯类化合物,经红外、紫外、高分辨质谱和多种一维和二维核磁共振谱鉴定,确定了其骨架结构及顺反构型,命名为马兜铃酸萜酯I。  相似文献   
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BACKGROUND: Kell is a major antigenic system in human red cells, with more than 20 identified antigens. KEL1 and KEL2 are two opposing low- and high-frequency alleles. Immunization to KEL1 is clinically significant, because anti-KEL1 can cause severe reactions to transfusion of incompatible blood, as well as hemolytic disease of the newborn. At the nucleotide level, the difference between the KEL2 and KEL1 alleles is a single-base change within exon 6 that results in the substitution of methionine (ATG) for threonine (ACG) at position 193. STUDY DESIGN AND METHODS: An assay using polymerase chain reaction and sequence-specific primers to genotype for the KEL1 and KEL2 alleles has been developed. It uses two allele-specific forward primers for either KEL1 or KEL2 and a single reverse-consensus primer. RESULTS: A validation study of 42 serologically typed samples (5 KEL:1,-2 [K+k-]; 23 KEL:1,2 [K+k+]; and 14 KEL:-1,2 [K-k+]) was performed. A concordance rate of 100 percent (42/42 samples) was observed between polymerase chain reaction with sequence-specific primers and serologic typing. CONCLUSION: This rapid, nonradioactive, Kell system genotyping assay does not require the additional steps of probe hybridization or restriction enzyme digestion. This application of polymerase chain reaction with sequence-specific primers should prove particularly useful in Kell system genotyping of amniotic cells to identify pregnancies at risk for hemolytic disease of the newborn.  相似文献   
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