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Abstract: Data from the National Education Longitudinal Study were combined with census data at the zip code level to examine the impact of neighborhood racial and ethnic diversity and consolidated inequality, in addition to individual, family, and school factors, on the likelihood of dropping out of high school. Results indicate that while the effects for diversity and consolidated inequality did not support the stated hypotheses, main effects for family risk and prior academic achievement were significant and in the stated direction. Also, when controlling for individual, family, school, and neighborhood characteristics, African Americans were less likely than White students to drop out of school. Implications for contextual effects research and educational outcomes are discussed. 相似文献
3.
D J Bowen 《Journal of clinical pathology》2002,55(1):1-18
This review focuses on selected areas that should interest both the scientist and the clinician alike: polymorphisms within the factor VIII and factor IX genes, their linkage, and their ethnic variation; a general assessment of mutations within both genes and a detailed inspection of the molecular pathology of certain mutations to illustrate the diverse cause–effect relations that exist; a summary of current knowledge on molecular aspects of inhibitor production; and an introduction to the new areas of factor VIII and factor IX catabolism. An appendix defining various terms encountered in the molecular genetics of the haemophilias is included, together with an appendix providing accession numbers and locus identification links for accessing gene and sequence information in the international nucleic acid databases. 相似文献
4.
Aaron M Kipp Jennifer A Lehman Richard A Bowen Patricia E Fox Michael R Stephens Kaci Klenk Nicholas Komar Michel L Bunning 《The American journal of tropical medicine and hygiene》2006,75(4):688-690
To better understand the potential environmental health risk presented by West Nile virus (WNV)-contaminated feces, we quantified the amount of WNV present in the feces of experimentally infected American crows (Corvus brachyrhynchos) and fish crows (Corvus ossifragus). Peak fecal titers ranged from 10(3.5) to 10(8.8) plaque-forming units (PFU)/g for 10 American crows and from 10(2.3) to 10(6.4) PFU/g for 10 fish crows. The presence of infectious WNV in bird feces indicates a potential for direct transmission of WNV. Thus, handlers of sick or dead birds should take appropriate precautions to avoid exposure to fecal material. 相似文献
5.
胰岛素抵抗和脑血管病关系的研究 总被引:1,自引:0,他引:1
目的:探讨胰岛素抵抗与脑梗死、脑出血的关系,为针对胰岛素抵抗的治疗可以有效地预防脑血管疾病提供理论依据。方法:选取42例脑梗死(脑梗死组)、40例脑出血(脑出血组)及30例非脑血管病患者(对照组),分别测定空腹胰岛素(FINS)、空腹血糖(FBG),计算胰岛素敏感指数(ISI),各组间进行比较。结果:脑梗死组和脑出血组患者ISI低于对照组(P〈0.05),而FINS高于对照组(P〈0.05),FBG与对照组差异无统计学意义(P〉0.05)。结论:胰岛素抵抗可能是脑血管病的一个重要危险因素。 相似文献
6.
Pamela K. Green Deborah J. Bowen Mark Kestin Ziding Feng 《Journal of Applied Biobehavioral Research》1993,1(2):174-198
There is evidence that long-term maintenance of a low-fat diet reduces preference for high-fat foods. Sensory evaluation of the taste of fat, and preference for high and low-fat foods were studied in a group of former participants in a randomized dietary intervention trial aimed at lowering fat consumption. Intervention subjects consuming less than 25% of daily calories as fat and control subjects consuming more than 35% of daily calories as fat agreed to be in a "taste perception" study. In Study 1, subjects tasted 20 dairy solutions containing different levels of fat and sugar. Subjects rated the perceived intensity of fat taste, and of liking, for each of the solutions. In Study 2, subjects were asked to taste and rate 4 high-fat and 4 low-fat snack foods, and were then allowed to freely consume these foods in a preference test. Intervention and control subjects were similar in their sensory evaluation of the taste of fat in Study 1. In Study 2, intervention subjects reported a reduced hedonic rating of the taste of high-fat snack foods compared to control subjects, yet intervention subjects consumed the same amount of high-fat snack foods as control subjects. We conclude that a successful outcome in a dietary intervention may be due to social and cognitive factors, in addition to potential changes in hedonic response to fat. 相似文献
7.
8.
颅内假性动脉瘤的手术治疗 总被引:4,自引:0,他引:4
目的探讨颅内假性动脉瘤的诊断和手术方法。方法回顾性分析16例手术治疗的颅内假性动脉瘤病人的临床及影像学特点.其中创伤性9例,感染性7例。结果出院时临床状况优良11例,轻残3例,死亡2例(其中1例为创伤性,术后发生脑梗死)。对12例行3个月。5年门诊随访,均未发生再出血。结论颅内假性动脉瘤是颅内动脉瘤中特殊且较复杂的类型,其诊断和处理策略与一般动脉瘤不同。提高对颅内假性动脉瘤的认识,以及有效应用神经外科技术,可以降低假性动脉瘤的手术风险,改善预后。 相似文献
9.
Y. W. Loke A. King T. Burrows L. Gardner M. Bowen S. Hiby S. Howlett N. Holmes D. Jacobs 《Tissue antigens》1997,50(2):135-146
A monoclonal antibody to HLA-G has been generated by immunizing HLA-A2.1/human β2 -microglobulin (β2 m) double transgenic mice with murine L cells transfected with both human β2 m and HLA-G. This monoclonal antibody, designated as G233, has been found not to cross-react with other HLA class I antigens when tested on numerous cell lines by flow cytometry. With immunohistology, all populations of extravillous trophoblast (cell columns, interstitial trophoblast, endovascular trophoblast, placental bed giant cells) were stained. An extensive range of adult and fetal tissues was also tested but none reacted with monoclonal antibody G233, including those previously reported to express HLA-G mRNA, indicating that the protein has a highly restricted distribution. Failure to detect HLA-G in the fetal thymus raises the question as to how T-cell tolerance to this antigen is induced. Immunoprecipitation of trophoblast surface proteins with monoclonal antibody G233 revealed a heavy chain of 39 kDa and a light chain of 12 kDa, indicating that HLA-G expressed on the surface of trophoblast is complexed with p2m. However, sequential immunoprecipitation with monoclonal antibody W6/32 followed by monoclonal antibody G233 continued to detect a residual band of 39 kDa, suggesting that trophoblast surface HLA-G may also occur as free heavy chains not associated with p2m. Immunoprecipitation followed by two dimensional gel electrophoresis showed that monoclonal antibody G233 recognizes several iso-forms of HLA-G from trophoblast similar to the characteristic spot array previously described for HLA-G. This monoclonal antibody G233 will be highly useful in future experiments to elucidate the function of HLA-G. 相似文献
10.
Thanh GN Ton Mary Anne Rossing Deborah J Bowen Sengkeo Srinouanprachan Kristine Wicklund Federico M Farin 《Behavioral and brain functions : BBF》2007,3(1):22-10