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291.
A modification of quantitative absorption and absorption elution tests with blood stain washing before the absorption phase is presented. Due to washing, the effect of carrier object on anti-Le(a) and anti-Le(b) sera is decreased and the sensitivity of the method is increased. Additional adsorption of the sera and elution into test erythrocytes treated with protease C is suggested for increasing the number of standard sera fit for the absorption-elution test. A new technology for preparing anti-Le(a) and anti-Le(b) immunoreagents is described.  相似文献   
292.
Recent research has indicated that vulnerable incarcerated young offenders--such as those at risk of suicidal behaviour, those on formal protection due to their inability to assimilate into mainstream, and those who are bullied but remain in normal circulation--display impoverished problem-solving abilities. Furthermore, deficits in their problem-solving skills are significantly correlated with levels of anxiety, depression, and hopelessness. This study evaluated the effectiveness of a time-limited, group-based problem-solving training intervention compared with a no-treatment control for vulnerable, incarcerated young offenders. A total of 46 young offenders were equally allocated to intervention or control groups. Intervention participants experienced significant reductions in their levels of anxiety, depression, and hopelessness and improvement in their self-assessed social problem-solving abilities. Gains in aspects of self-assessed problem-solving ability and mental health for the intervention group continued to be evident at 3-month follow-up. Methodological concerns in this study and directions for future research are discussed.  相似文献   
293.
In a double-blind placebo controlled study on psychomotor skills important for car driving (Study 1), a 75 mg dose of +/- 3,4-methylenedioxymethamphetamine (MDMA) was administered orally to 12 healthy volunteers who were known to be recreational MDMA-users. Toxicokinetic data were gathered by analysis of blood, urine, oral fluid and sweat wipes collected during the first 5h after administration. Resultant plasma concentrations varied from 21 to 295 ng/ml, with an average peak concentration of 178 ng/ml observed between 2 and 4h after administration. MDA concentrations never exceeded 20 ng/ml. Corresponding MDMA concentrations in oral fluid, as measured with a specific LC-MS/MS method (which required only 50 microl of oral fluid), generally exceeded those in plasma and peaked at an average concentration of 1215 ng/ml. A substantial intra- and inter-subject variability was observed with this matrix, and values ranged from 50 to 6982 ng/ml MDMA. Somewhat surprisingly, even 4-5h after ingestion, the MDMA levels in sweat only averaged 25 ng/wipe. In addition to this controlled study, data were collected from 19 MDMA-users who participated in a driving simulator study (Study 2), comparing sober non-drug conditions with MDMA-only and multiple drug use conditions. In this particular study, urine samples were used for general drug screening and oral fluid was collected as an alternative to blood sampling. Analysis of oral fluid samples by LC-MS/MS revealed an average MDMA/MDEA concentration of 1121 ng/ml in the MDMA-only condition, with large inter-subject variability. This was also the case in the multiple drug condition, where generally, significantly higher concentrations of MDMA, MDEA and/or amphetamine were detected in the oral fluid samples. Urine screening revealed the presence of combinations such as MDMA, MDEA, amph, cannabis, cocaine, LSD and psilocine in the multiple-drug condition.  相似文献   
294.
The aim of the present investigation was to reconstruct the chronological age based on the dental developmental stages of third molars evaluated on orthopantomograms. A total of 1175 orthopantomograms were assembled from patients of Caucasian origin between 16 and 22 years of age. Each third molar present was scored by two observers according to a 10-stage developmental scale. The kappa statistics measured the intra- and inter-observer reliability. The general statistical analysis was based on multiple regression analysis in order to obtain multiple regression formulas for dental age estimation based on the number of third molars present on the evaluated orthopantomogram. No regression models were statistically significant when there was only one-third molar present because of the relatively small number of orthopantomograms that fitted this criterion. A strong agreement was found between the intra- and inter-observer measurements. The statistical analysis revealed both for males and females high Pearson correlation coefficients between contralateral third molars and smaller coefficients between antimeres. The obtained multiple regression formulas are only applicable in certain specified conditions, for instance when four third molars are present the following formulas should be used in a Caucasian male "age=10.2000+0.5122UL+0.5273LL" (developmental stage of upper and lower left third molars) or in case of a female "age=13.6206+0.1933UR+0.5080LR" (developmental stage of upper and lower right third molars). This investigation revealed that the chronological age of a Caucasian individual may be estimated based on regression formulas with a S.D. of 1.52 or 1.56 years for males and females, respectively, when all four third molars are present.  相似文献   
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This article examines the prevalence and consequences of authoritarian attitudes among elites in Argentina, Brazil, Chile, Colombia, Mexico, and Venezuela. We focus on the connection between antidemocratic elite attitudes and support for democracy; the causes and effects of authoritarian attitudes among elites and their implications for authoritarianism; and the impact of authoritarian attitudes beyond social policy preferences to other policy areas that have indirect implications for order. Contrary to some of the literature, we find that antidemocratic attitudes affect elites' support for democracy. Our analysis also speaks to the debate on the origins of authoritarianism. Much of the evidence supports Altemeyer's notion that perceived threat raises levels of authoritarianism, rather than Feldman's contention that threat strengthens the influence of authoritarian attitudes. Finally, we demonstrate that there is a broader influence of authoritarian attitudes on economic policy preferences, but only where those policies appear to have implications for social order.  相似文献   
297.
Several recent studies examine the degree to which congressional behavior affects candidates’ electoral fortunes (e.g., Carson, 2005). Research examining electoral competitiveness (Bond, Campbell, & Cottrill, 2001; Koetzle, 1998) and roll call voting (Bailey & Brady, 1998; Jones, 2003) finds that diversity in the electorate mediates the impact of numerous variables upon election outcomes and representation. However, the influence of diversity on other modes of representation – such as the policy positions taken by Senate candidates–remains unexplored. We investigate the link between representation and Senate candidates’ policy positions and thereby examine the degree to which voter diversity affects candidates’ policy responsiveness. We find that diversity significantly influences responsiveness, both directly and indirectly – candidates in homogenous states are more responsive to constituents than are candidates in heterogeneous states.  相似文献   
298.
The horrifying, tragic events of 9/11 made Americans aware of their vulnerability to terrorist attacks and triggered the creation of the Department of Homeland Security along with a substantial increase in federal spending to both thwart terrorist attacks and to increase our ability to respond to such emergencies. Much of this large increase in spending was in the form of direct transfers to states and cities through several grant programs. Homeland Security grants may be used for protection against terrorist activities, thereby enhancing public interests, or as wealth transfers to state and local governments, enhancing the reelection efforts of incumbents, and thus, private interests. Using 2004 per capita Homeland Security grant funding to states and their cities, we find that the funding formula used for some of the grant programs, which allocates almost 40% of the funds in some grant programs through a minimum percent to each state with the rest allocated based on population, means that per capita funding is related to electoral votes per capita, i.e., to the politics of Presidential re-election. However, the funding in other grant programs is also related to some of the dangers and vulnerabilities faced by states and their cities. Some of the variation in per capita grant allocations is also explained by the amount of airport traffic in the state and the state's population density, which are variables closely linked to the state's vulnerability to attack. Per capita Homeland Security grant allocations, however, do not seem to be related to the closeness of the 2000 presidential race.  相似文献   
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