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41.
Detection of diatoms in blood by a combination of membrane filtering and chemical digestion 总被引:2,自引:0,他引:2
An improved method for detecting diatom in blood is reported. Blood of cadavers was obtained by cardiac puncture at inquest or from the left atrium directly at autopsy. The blood was hemolyzed by sodium dodecyl sulfate (SDS) and filtered through membrane filter (47 mm in diameter and 5 microns in pore size). When the blood was putrefied, two or three pieces of membranes filters were needed because of choking membrane pore. The membrane filters were digested with fuming nitric acid and diluted with distilled water. The diluted solution was filtered through membrane filter (25 mm in diameter) again. After drying the membrane filter was immersed in oil. Diatoms on the membrane filter were clearly observed microscopically. 相似文献
42.
Chan TY 《Forensic science international》2012,222(1-3):1-3
Although proprietary medicines and decoction of processed aconite roots are the most widely used, tincture accounts for the great majority of aconite poisoning cases in China, indicating that it is much more toxic than other formulations. Aconite tincture is often self-prepared at home and raw aconite plants or roots are often used. Even if processed aconite roots were used to make the tincture, the amount of Aconitum alkaloids is highly variable, depending on the adequacy of processing and quality control. Aconitum alkaloids dissolve efficiently in alcohol. For these reasons, tincture contains very high concentrations of Aconitum alkaloids. Despite its high intrinsic toxicity, overdose of aconite tincture by the users has been common. Severe aconite poisoning can be complicated by fatal ventricular tachyarrhythmias and asystole. The public should be repeatedly warned of the danger of taking aconite tincture by mouth. 相似文献
43.
涉及死亡非医疗过失纠纷的类型,死因和发生原因——27年医疗纠纷法医尸检回? 总被引:7,自引:0,他引:7
对1992~1998年间206例非医疗过失尸检资料进行回顾性研究,表明涉及死亡的非医疗纠纷中各类疾病死亡占53.88%,难以避免的并发症占39.81%,医疗意外占6.31%.发生原因中对死因怀疑占44.66%,怀疑输液(血)错误占15.05%,怀疑治疗出问题占9.71%,怀疑用药错误或诊治延误各占8.74%,其它13.11%与医护人员态度不好、医院管理有关. 相似文献
44.
Hsieh HM Chiang HL Tsai LC Lai SY Huang NE Linacre A Lee JC 《Forensic science international》2001,122(1):7-18
A partial DNA sequence of cytochrome b gene was used to identify the remains of endangered animals and species endemic to Taiwan. The conservation of animals species included in this study were: the formosan gem-faced civets, leopard cats, tigers, clouded leopards, lion, formosan muntjacs, formosan sika deers, formosan sambars, formosan serows, water buffalo, formosan pangolins and formosan macaques. The control species used included domestic cats, domestic dogs, domestic sheeps, domestic cattles, domestic pigs and humans. Heteroplasmy was detected in the formosan macaque, domestic pig and domestic cats. The frequencies of heteroplasmy in these animals were about 0.25% (1 in 402bp). Sequences were aligned by Pileup program of GCG computer package, and the phylogenetic tree was constructed by the neighbor-joining method. The results of sequence comparison showed that the percentage range of sequence diversity in the same species was from 0.25 to 2.74%, and that between the different species was from 5.97 to 34.83%. The results of phylogenetic analysis showed that the genetic distance between the different species was from 6.33 to 40.59. Animals of the same species, both the endangered animal species and domestic animals, were clustered together in the neighbor-joining tree. Three unknown samples of animal remains were identified by this system. The partial sequence of cytochrome b gene adopted in this study proved to be usable for animal identification. 相似文献
45.
46.
This study examined the factors associated with resistance to peer pressure toward antisocial behaviors among a sample of Mexican-origin adolescents (n=564) living in a large Southwestern city in the U.S. A model examining the influence of generational status, emotional autonomy from parents, and self-esteem on resistance to peer pressure was tested independently for boys and girls. Gender differences emerged in the factors that influenced resistance to peer pressure. Results indicated that resistance to peer pressure was influenced by generational status and emotional autonomy from parents for both boys and girls. However, self-esteem was found to influence resistance to peer pressure only for boys.Mayra Y. Bámaca is a graduate student in Family and Human Development at Arizona State University. Her research interests include adolescent development among ethnically diverse populations, the influence of contextual factors in development, parenting adolescents, and resiliency among Latino adolescents and their families. This work was based on the master’s thesis of the first author.Adriana J. Uma?a-Taylor received her Ph.D. from the University of Missouri-Columbia and is currently an Assistant Professor of Family and Human Development at Arizona State University. Her research interests include ethnic identity formation during adolescence and resilience among Latino adolescents and their families.This study was supported, in part, by a grant to the second author from the Fahs Beck Fund for Research and Experimentation of the New York Community Trust. 相似文献
47.
48.
The purpose of the present investigation was to test the accuracy of a new scoring system in recording tooth wear for age estimation. The material consisted of dental stone casts of 383 volunteers who had sound premolars and molars with normal occlusion. The degree of occlusal wear for all premolar and molar teeth was scored with the new system. The high intra- and inter-examiner concordances showed that the new score system was very reliable. The degree of tooth wear showed a significant positive correlation with age in each and every examined tooth of both males and females. Tooth wear scores of males were higher than those of females. Calculating tables for age estimation were designed and the accuracy of age estimation was obtained with the General Linear Models procedures. Our system could provide estimation of an individual's age within +/-3 years in 42.4% of males and 49.4% of females, within +/-5 years in 61.8% of males and 63.3% of females. When the subjects were divided into two age groups and data were re-treated, the accuracy of age estimation was increased. Collectively, it was shown that our new system for scoring tooth wear is a reliable and accurate method for age estimation. 相似文献
49.
An accurate and simple method was developed to determine the level of toluene in urine and blood quantitatively by using the gas chromatography/mass spectrometry (GC/MS) with headspace--solid phase microextraction (HS-SPME) technique. An assembly of SPME with a replaceable extraction fiber, coated with 100 microm polydimethylsiloxane, was used. The detection limit of toluene in blood and urine with HS-SPME technique was 10 times higher than that with headspace (HS) technique. To compare the HS-SPME with HS technique for the determination of toluene in biological fluids, blood and urine samples from glue sniffers were analyzed by both methods. The level of toluene by the two techniques was highly correlated: the correlation coefficient (r2) between the two sets of values were 0.98 and 0.96 in urine and blood, respectively. 相似文献
50.
A blood group substance (BGS), a protein with ABH antigenic activity, was isolated from human seminal plasma and designated as p 84 (Sato, 1995). We have developed a method for determining the ABO blood type of semen by performing a sandwich enzyme-linked immunosorbent assay (ELISA) in which p 84 is captured with an anti-p 84 monoclonal antibody, and evaluated the specificity and sensitivity of this method. Although BGS activity was detected in semen sensitively by this method, it was not detected in saliva, urine, breast milk, blood or vaginal secretions. Since the concentration of p 84 in semen was independent of the secretion status, the status can be determined as non-secretor when p 84 but not BGS activity was detected. To determine the stability of BGS activity on p 84, dried stains of semen on filter paper were kept at 4, 26, and 37 degrees C for 8 months, 2 years and 1 month, respectively, and their BGS activities were examined. After 8 months at 4 degrees C, over 60% of the original BGS activity was recovered from the stain. The activity could be detected even from a square as small as 0.25 by 0.25 cm. After 1 month at 37 degrees C and 2 years at 26 degrees C, 31 and 20% of the BGS activity, respectively, still remained. It could be detected from the pieces of 1.0 by 1.0 cm and 0.5 by 0.5 cm squares, kept for 1 month at 37 degrees C and 2 years at 26 degrees C, respectively. Finally, semen was mixed with saliva or blood at varying volumetric ratios and used for the sources of dried stains. The BGS activity of p 84 could be detected in the stains until the ratio between semen and saliva or blood reached 1:4. We conclude that this sandwich ELISA offers a more sensitive and specific method for determining the ABO blood type of semen samples obtained from sexual assault victims than existing methods, such as the conventional absorption-elution and classical hemagglutination-inhibition tests. 相似文献