Spectra interference between diquat and paraquat by second derivative spectrophotometry

A rapid and accurate method, combining solid-phase extraction and second-order derivative spectrophotomety approaches, is developed for the simultaneous determination of diquat (DQ) and paraquat (PQ) in blood, tissue and urine samples. Supernatant resulting from the precipitation of protein (with trichloroacetic acid) in plasma and tissue or Amberlite IRA-401 resin treated urine are passed through a mini-column packed with Wakogel gel (Silica gel). Analytes are then eluted with a non-organic solvent, 0.2mol/l HCl solution containing 2mol/l NH(4)Cl. UV spectrum of the eluent in 220-350nm range provides effective screen to detect the presence of DQ and/or PQ. In the presence of DQ or PQ alone, the analyte present is quantitated by conventional zero- or second-order derivative spectrophotometry. The calibration curve in the 0.1-5.0mg/l range for either analyte obeys Beer's law. When both DQ and PQ are present, their concentrations are determined by the peak amplitudes of their respective second-derivative spectra after the addition of alkaline dithionite reagent. Interference is negligible when the DQ/PQ concentration ratio is within the 5.0-0.2 range.Using a 2-ml of sample size, the detection limits for DQ and PQ in plasma are 0.02 and 0.005mg/l. The corresponding detection limits for urine samples (10ml sample size) are 0.004 and 0.001mg/l. Recoveries of DQ and PQ in triplicate plasma and urine samples spiked with 0.5mg/l of analytes are 93 and 85%. The precision of the proposed method resulting from triplicate study of spiked urine samples varies from 3.2 to 4.6% at 0.5mg/l of DQ and PQ, respectively.     

大鼠脑挫伤后FN表达与损伤时程关系的研究

为寻找推断脑损伤经历时间的可靠指标,采用自制自由落体撞击法致大鼠右顶叶局灶性脑挫伤模型,于不同时间段处死大鼠后,进行纤维连接蛋白的免疫组织化学及原位杂交法研究,结果发现纤维连接蛋白及其 mRNA表达水平与伤后经历时间有一定相关性,并能较好地鉴别死前脑挫伤和死后脑挫伤,可作为推断脑挫伤经历时间的参考指标之一。     

线粒体 DNA突变与心肌病关系的研究进展

人类某些疾病与线粒体DNA(mtDNA)基因组缺陷有关.本文就mtDNA突变与缺血性心肌病和肥厚型心肌病关系的研究加以回顾.目前的研究大多认为心肌缺血缺氧致氧化磷酸化紊乱,产生氧自由基损伤mtDNA,以及缺氧致氧化磷酸化过度诱导而损伤mtDNA,慢性损伤积累终致mtDNA片断缺失或点突变,主要表现出mtDNA5.0kb、7.4kb缺失及细胞色素b(cytb)基因上C15452A点突变;tRNA基因保守序列突变,致肌肉收缩蛋白合成缺陷,缺陷的收缩蛋白持续而无效的收缩可能会增加心肌对ATP的代谢需求,因此导致心肌肥厚.     

邓小平对毛泽东统战理论的新发展及其时代特征

新时期邓小平在关于统一战线的性质和范围、关于知识分子地位和作用、关于多党合作和政治协商制度、关于"一国两制"与和平统一方针等方面对毛泽东统战理论作出新的发展,表现出邓小平统战理论具有鲜明的时代特征,即创造性、科学性、可行性、原则性、灵活性、广泛性.     

Initiation of formal death investigation procedures among the Northern Plains Indians: a necessary adjunct in the study of American Indian sudden infant deaths

The high rate of infant mortality among native peoples in the Aberdeen Service Area of the Indian Health Service (primarily North and South Dakota) prompted a multi-institutional study of this problem. The study investigators assumed that local coroners or medical examiners would be able to perform suitable death scene investigations. However, during the design portion of the study it became apparent that, with one exception, none of the participating Indian Nations had a death investigator or even a legal mandate to provide death investigation. To allow the study to go forward, and ultimately to better the community health within its service area, the Aberdeen Area Indian Health Service submitted a draft enabling coroner legislation/resolutions to the area tribes. By November of 1996, 6 of the 19 Indian Nations enacted enabling coroner legislation. To facilitate both the study and general death investigation within the area, the Aberdeen Area Indian Health Service since 1993 has held five 2-day death investigation training programs covering a variety of death investigation topics which were attended by 68 participants. Without further recognition of the need for tribal death investigation and additional funding, these gains in tribal death investigation will probably be transitory.     

Using the good cop/bad cop profile with the MMPI-2

The Minnesota Multiphasic Personality Inventory (MMPI) has been widely used in a variety of ways to screen candidates for law enforcement positions. This study extends the use of the MMPI Good Cop/Bad Cop (GC/BC) profile (Blau, Super, & Brady, 1993) to the MMPI-2. The MMPI-2 profiles of 39 veteran police officers were used to predict their performance (No Apparent Problems, Borderline, or Serious Problems Possible), and these predictions were compared with supervisors’ ratings of the officers’ actual performance. The MMPI-2 predictions were accurate for 46% of the officers, a rate that was significantly better than chance (p=.024). Based on the current data, the best selection outcome would be obtained by accepting officers whose MMPI-2 profiles place them in the No Apparent Problems or Borderline groups, and rejecting officers whose profiles suggest Serious Problems Possible. This could be accomplished simply by rejecting any officer who obtained a score above 65T on any of the clinical scales. This selection strategy would have resulted in the acceptance of 22 officers, 19 of whom were highly rated by their supervisors, and the rejection of 17 officers, 11 of whom were rated as borderline or poorer by their supervisors. It would also result in the erroneous rejection of 6 officers who were highly rated by supervisors. AUTHOR NOTE: An earlier version of this paper was presented at the 1994 annual meeting of the Society for Police and Criminal Psychology, in Roswell, New Mexico. The authors wish to thank Jim Herndon, Ph.D., for this comments on this study.     

Mediators of the Relation Between Beliefs in a Just World and Emotional Responses to Negative Outcomes

Research shows that strong believers in a just world respond with less negative and more positive emotion to their own negative outcomes than do weak believers. The present study investigated mediators of this relation. We proposed that strong believers in a just world (versus weak believers) would make stronger internal and weaker external attributions for their negative outcomes, leading to reduced perceived unfairness, which, in turn, was expected to lead to less negative and more positive emotion. We assessed the just world beliefs of a sample of undergraduates as well as measuring their cognitive and emotional responses to an exam grade. Mediational analyses showed that our data were consistent with the processes proposed above. Various cognitive and motivational interpretations of the present findings are discussed