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1.
Isoenzyme band patterns of animal blood erythrocyte acid phosphatase (EAP) and phosphoglucomutase-1 (PGM) were studied by isoelectric focusing on ultrathin polyacrylamide gels. For blood from all animals tested (dog, cat, cow, sheep, and goat), the overall band patterns for both isoenzymes were different from those of the most common human types of these enzymes, although some animal EAP and PGM bands appeared in the human band areas. When mixtures of human and animal red blood cells were studied, it was found that misinterpretation of human types was possible only if the overall band pattern of the mixtures was ignored. For the animal blood tested, the strong PGM bands appearing outside the human band areas could be used as "markers" for the possible presence of animal blood in the samples tested.  相似文献   
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A sandwich ELISA for human prostate-specific antigen (PSA) is described. Optimal assay conditions, resulting in a sensitive assay with a low background, are presented. The method uses a hyperimmune antiserum produced in the New Zealand white rabbit, against human semen PSA. The IgG fraction of the antiserum was conjugated with horseradish peroxidase and used in the sandwich ELISA method. The anti-PSA IgG showed no cross reactions with saliva, normal blood, female urine, vaginal fluid, or menstrual blood. On occasions, a blood sample showed a non-specific cross-reaction, which was detected by non-immune rabbit IgG. This reaction could be caused by rheumatoid factors, as indicated by experiments with a series of known IgG and IgM rheumatoid antibodies, although other heterophilic antibodies could not be eliminated. The recovery of PSA added to blood plasma, saliva and vaginal fluid was affected by three factors; (a) protein concentration (dilution) of body fluid; (b) nature of the protein; and (c) amount of PSA added.  相似文献   
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Numerous studies and interventions have been designed to either reduce the prevalence of risky behaviors (substance use, sexual activity, etc.) or increase the level of educational activity for adolescents. Research suggests that these two constructs may be related yet little is known about this relationship among African American youth. Archival data from the Risk Reduction Project was used to explore the connection between the protective factors of educational aspirations/expectations and recent participation in risky behavior. Results suggest that recent use of marijuana, alcohol to the point of intoxication, and sexual activity predicted lower aspirations and expectations among African American youth. From a positive youth development perspective, this study suggests the development of holistic interventions that build educational assets in youth, in addition to working to minimize risk behaviors. Limitations and suggestions for future research are also discussed.  相似文献   
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Blood alcohol concentrations (BAC) and corresponding breath alcohol concentrations (BrAC) were determined for 21,582 drivers apprehended by New Zealand police. BAC was measured using headspace gas chromatography, and BrAC was determined with Intoxilyzer 5000 or Seres Ethylometre infrared analysers. The delay (DEL) between breath testing and blood sampling ranged from 0.03 to 5.4 h. BAC/BrAC ratios were calculated before and after BAC values were corrected for DEL using 19 mg/dL/h as an estimate of the blood alcohol clearance rate. Calculations were performed for single and duplicate breath samples obtained using the Intoxilyzer (groups I-1 and I-2) and Seres devices (groups S-1 and S-2). Before correction for DEL, BAC/BrAC ratios for groups I-1, I-2, S-1, and S-2 were (mean+/-SD) 2320+/-260, 2180+/-242, 2330+/-276, and 2250+/-259, respectively. After BAC values were adjusted for DEL, BAC/BrAC ratios for these groups were (mean+/-SD) 2510+/-256, 2370+/-240, 2520+/-280, and 2440+/-260, respectively. Our results indicate that in New Zealand the mean BAC/BrAC ratio is 19-26% higher than the ratio of the respective legal limits (2000).  相似文献   
6.

Objectives

The temporal variation in homicide is examined by studying trends in race/ethnic specific killings (e.g. Blacks, Latinos and Whites). Two substantively important issues are also addressed—a closer examination of the role community heterogeneity plays in homicide levels and the treatment of immigration as an endogenous social process.

Methods

Data are reported homicides in the city of San Diego, California over the period 1960–2010. The address of each killing is geocoded into 341 census tracts.

Results

We find that neighborhoods experiencing increases in the foreign-born population tend to be less violent. White and Latino homicide victimization was reduced significantly as a product of increases in the neighborhood concentration of foreign-born individuals. Supplementary analyses did not find empirical evidence that the influx of foreign-born individuals could (or should) be considered a disruptive social process. Over the past five decennial census periods, the exponential increase in immigration in this border city is not associated with an increase in homicide victimization.

Conclusions

When examined through a wider temporal lens than is typically employed, and accounting for the endogeneity of immigrant residential settlement, we find no support for the claims that immigration is a crime generating social process.
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The isoenzymes erythrocyte acid phosphatase and phosphoglucomutase were typed in mixed red cell samples which had been derived from two individuals; the protein group specific component was typed in mixed serum samples. Typing was performed by isoelectric focusing on ultrathin polyacrylamide gels. Depending upon the mixture, from 2 to 20% (but typically 5-10%) by volume of a second blood or serum needed to be present in a mixture before it could be detected. In the majority of cases when there was significant mixing, samples were readily identified as a mixture when the results consisted of unusual band patterns or unusual band intensities. There would be a few instances when blood or serum could not be identified as a mixture when masking effects occurred or when the mixture produced a combined, apparently normal, pattern.  相似文献   
10.
Numerous studies and interventions have been designed to either reduce the prevalence of risky behaviors (substance use, sexual activity, etc.) or increase the level of educational activity for adolescents. Research suggests that these two constructs may be related yet little is known about this relationship among African American youth. Archival data from the Risk Reduction Project was used to explore the connection between the protective factors of educational aspirations/expectations and recent participation in risky behavior. Results suggest that recent use of marijuana, alcohol to the point of intoxication, and sexual activity predicted lower aspirations and expectations among African American youth. From a positive youth development perspective, this study suggests the development of holistic interventions that build educational assets in youth, in addition to working to minimize risk behaviors. Limitations and suggestions for future research are also discussed.  相似文献   
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