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Reliable, sensitive, rapid and quantitative enzyme-based assay for gamma-hydroxybutyric acid (GHB) 总被引:1,自引:0,他引:1
Several assays for gamma-hydroxybutyrate (4-hydroxybutyrate, GHB) have been developed based on the enzyme gamma-hydroxybutyrate dehydrogenase (GHB-DH). Enzymatic oxidation of GHB by NAD+ is coupled to diaphorase-mediated reduction of pro-dye to yield colored product. GHB-DH from Ralstonia eutropha was cloned and expressed as a stable fusion protein easily purified by affinity chromatography. Quantitative initial velocity and endpoint versions of the assay in solution are described. Michaelis-Menten parameters for oxidation of GHB and ethanol were estimated. A semi-quantitative "dipstick" version of the assay on paper also is described. Both solution endpoint and "dipstick" assays are sensitive to about 0.05 mg GHB/mL using 10 microL of sample. Ethanol at concentrations possible in urine and agents used to stabilize physiological fluids for forensics analysis do not interfere significantly. The "dipstick" assay also allows detection of GHB in alcoholic beverages after evaporation of about one-fourth drop of beverage before testing. The enzymatic assay for GHB is reliable, sensitive, inexpensive and rapid. 相似文献
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The article describes a study of the perceptions of three groups--patients, orthopaedic surgeons and the surgeons' practice managers--concerning three types of legal risk associated with the duty of care: failure to follow up, failure to warn and failure to diagnose. The study found there is cause for concern about doctors' follow-up and documentation of patient care. Doctors may be unaware of the Australian courts' propensity to emphasise practitioner responsibility rather than patient autonomy. A further important result is the considerable disparity between the surgeons' views and the views of their practice managers about the duty of care. The article draws out implications for improved risk awareness and suggests further research. 相似文献
76.
Rogel MJ Zuehlke ME Petersen AC Tobin-richards M Shelton M 《Journal of youth and adolescence》1980,9(6):491-506
The contraceptive behavior of adolescent girls was viewed from a decision-making perspective. A semistructured interview protocol was used in interviewing 120 girls aged 12–19 in three clinics (Teen Family Planning, Prenatal, Pediatric Acute Care) at Michael Reese Hospital and Medical Center on (1) demographic in formation; (2) sexual and obstetric history; (3) contraceptive and sexual knowledge, attitudes, and practices; (4) environmental pressures; (5) personality factors; and (6) decision-making style. We found that the girls were generally poor contraceptors. They viewed the costs of contraception (in terms of safety) to be high; and they positively valued physical intimacy, opportunities for which come up unexpectedly and sporadically. These factors, along with their ambivalent views toward pregnancy and childbearing seemed to encourage their risk-taking behavior. Once pregnancy occurred, it was carried to term because of the strong internal and external pressures they felt to have and keep the baby. The peer-led intervention program that we are developing based on the survey findings will focus on (1) the teenagers' lack of accurate and complete knowledge about birth control and conception, (2) their limited sense of options concerning birth control and pregnancy outcomes, and (3) their poor understanding of and lack of insight into what motivates their behavior.This study is part of the investigation being conducted by the YADMAC (Young Adult and Adolescent Decision Making About Contraception) Project at Michael Reese Hospital and Medical Center, 2959 South Cottage Grove, Chicago, Illinois 60616. The authors are all members of the YADMAC research team.Received Ph.D. from the University of Chicago. Current interests are human sexuality and reproductive behavior. Currently at Department of Psychology, St. Xavier College.Received M.D. from the University of Michigan. Current interests are liaison child psychiatry and adolescent sexuality.Received Ph.D. from the University of Chicago. Current interests are early adolescent development issues.Current interests are puberty and sex differences.B. A. candidate in social work, Roosevelt University. Current interests are adolescent sexuality and contraceptive behavior. 相似文献
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In this article, we identify legal knowledge as a key difference between workers who desire workplace change and those who do not. Based on surveys with 121 day laborers, we find that not all day laborers are equally dissatisfied with their jobs, despite uniformly difficult working conditions. Some day laborers do not want to make any real changes to the day labor industry, while others desire a range of industry changes, from higher wages to greater government regulation and unionization. A key difference between these workers is their knowledge of employment law: Those who know the law are more likely to desire workplace change. 相似文献
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This paper explores a popular yet highly destructive form of property crime — graffiti vandalism. The localities of such destruction
selected for study were male and female restrooms. Three hundred and ninety-two cases were collected and analyzed. Prior research
theorized the existence of a significant difference in the amount of graffiti produced between the sexes. (It was believed
that males produce more graffiti than females). Analysis, however, revealed equal production of graffiti by males and females.Content differences between the sexes were hypothesized. The content categories included homosexual, heterosexual, nonsexual (humorous
and political statements) and racial graffiti. The findings as they relate to content differences between the sexes are presented
and discussed relative to sex-role socialization theory. 相似文献