首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The determination of blood groups from blood stains is extremely important in medicolegal practice, but there is the possibility of an error in the determination of MN phenotypes by the absorption-elution test. We investigated a new method applying electrophoresis and immunoblotting. As a consequence of various experiments, the most appropriate pretreatment of blood stains was as follows. Blood stains were immersed in physiological saline for 0.5 to 1 h and centrifuged. The supernatant was discarded. The sediment was dissolved in sample buffer (TRIS-buffered physiological saline containing 2% sodium dodecyl sulfate) and followed by thermodegradation. It was subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). After transfer to a nitrocellulose membrane by Western blotting, MN phenotypes could be determined accurately from blood stains by an enzyme immunoassay (EIA) using commercially available polyclonal anti-M and anti-N sera. For blood stains more than 1 month old it was not easy to determine the MN phenotypes.  相似文献   

2.
Radioimmunoassay of alpha 1-fetoprotein(AFP) for medico-legal identification of fetal blood stains using a commercial kit is described. The AFP content in fetal blood stains on filter paper ranged from 21--320 ng/9 mm2. The protein was detected in stains of adult blood and retroplacental blood in only negligible amounts. Aging of the blood stains did not influence the values up to 1 month. The method is simple and sensitive enough for application to medico-legal-practice.  相似文献   

3.
A new method for the identification of fetal hemoglobin (Hb F) in blood stains by reverse-phase high performance liquid chromatography is described. Differentiation between fetal and adult blood stains is based on the existence of gamma-chain peaks which are characteristics of Hb F. Very few gamma chains appeared on chromatograms of all the adult blood stains examined. The level of Hb F could be determined by measuring the total of chromatogram gamma-globin chain areas, and expressing it as a percentage of total Hb. Levels in six cord blood stains on filter paper ranged from 81.1% to 91.3% and remained constant for at least 12 weeks. This method is of great value for its simplicity, sensitivity and speed, and most importantly for its reliability in the field of forensic medicine.  相似文献   

4.
Non-destructive identification and subsequent age estimation of blood stains are significant steps in forensic casework. The latter can provide important information on the temporal aspects of a crime. As previously shown, visible spectroscopy of blood stains on white backgrounds can successfully be used for their identification and age estimation. The use of this technique however, is hampered by dark backgrounds. In the present study the feasibility to use near infrared (NIR) spectroscopy was evaluated for blood stain identification and age estimation on dark backgrounds. Using NIR reflectance spectroscopy, blood stains were distinguished from other substances with 100% sensitivity and 100% specificity. In addition, Partial Least Squares Regression analysis was applied to estimate the age of blood stains on colored backgrounds. The age of blood stains up to 1 month old was estimated successfully with a root mean squared error of prediction of 8.9%. These findings are an important step toward the practical implementation of blood stain identification and age estimation in forensic casework, where a large variety of backgrounds can be encountered.  相似文献   

5.
The specific activity (enzyme activity/protein concentration) of amylase was determined for the identification of saliva stains. The specific activity of amylase in saliva stains rapidly decreased during the first hour but, from 1 to 28 days, this decrease was much less when the stains were kept at room temperature. Stains of various human biological materials, breast milk, nasal secretion, meconium and vaginal secretion showed comparatively high amylase activity, but the saliva stains could be differentiated by their high specific activity of amylase, over 2 I.U./mg. When saliva stains were contaminated with blood or vaginal secretions at various ratios, the specific activity of amylase decreased with increase in the ratio of contaminant, especially when the contaminant was blood. However, the specific activity of amylase was still higher than 2 I.U./mg even after one fifth volume of blood was added or after five volumes of the extract of the stains of vaginal secretions were added.  相似文献   

6.
Bloodstain pattern analysis can be critical to accurate crime scene reconstruction. However, bloodstain patterns can be altered in the presence of insects and can confound crime scene reconstruction. To address this problem, we conducted a series of controlled laboratory experiments to investigate the effect of Lucilia sericata (Meigen) on impact bloodstains and pooled bloodstains in association with three combinations of common surfaces (linoleum/painted drywall, wood floor/wallpaper, and carpet/wood paneling). L. sericata fed from the pooled bloodstains and added insect stains through regurgitation and defecation of consumed blood. L. sericata formed defecatory trails of insect stains that indicated directionality. Defecatory stains fluoresced when viewed at 465 nm with an orange filter. These observations differed from Calliphora vicina insect stains because feeding on blood spatter was not observed and trails of insect stains were formed by L. sericata. The fluorescence of defecatory stains can be used as a method to detect insect stains and discriminate them from real bloodstains.  相似文献   

7.
<正> 1988年,壹岐裕志等报告了用吸附抗α_2-SGP 血清的硝化纤维素膜(NCF)检验混合斑中的精斑 ABO 血型,但耗时。本文作者通过对此方法的改进,采用常彩琴等研制的抗人精特异蛋白血清(anti-human seminalpeculiar protein,ASPP),采用蛋清粘片热解离法检验混合斑中精斑 ABO 血型,耗时短,效果好。现介绍如下。  相似文献   

8.
This study originated from discussions and recommendations of the Technical Working Group on DNA Analysis Methods (TWGDAM). Four bloodstain deoxyribonucleic acid (DNA) extraction protocols and five semen stain DNA extraction protocols were evaluated. Nine laboratories participated in the extraction of DNA from 20 bloodstains and 20 semen stains using each protocol. All blood and semen stains originated from a single donor and were prepared under uniform conditions to permit the direct comparison of DNA yields and restriction fragment lengths. The extracted DNA from approximately 600 bloodstains and 700 semen stains was quantified by yield gel analysis and a slot blot hybridization technique. The extracted DNA was digested and restriction fragment length polymorphism (RFLP) patterns were generated using three single-locus probes. The RFLP sizing data produced from the blood and semen stains were evaluated with respect to (1) DNA extraction method, (2) gel length, (3) agarose type, (4) presence or absence of ethidium bromide in the gel, and (5) fragment sizes obtained from DNA isolated directly from the donor's liquid blood. This study demonstrates conclusively that high-molecular-weight DNA can be isolated using either organic or nonorganic DNA extraction protocols and that the resulting RFLP sizes are highly reproducible regardless of gel length, agarose type, or presence/absence of ethidium bromide.  相似文献   

9.
10.
Sex determination of blood stains from women who were in the late stages of pregnancy was possible by detecting human placental lactogen (HPL) in them. However, the agglutination time for positive reactions was prolonged as the stains aged.  相似文献   

11.
DNA was extracted from human and non-primate dried blood stains. Human male and female specimens were readily distinguished by analysis with a Y-chromosome specific DNA probe. Human and non-primate blood stains were also readily differentiated using a repeat sequence (Alu) DNA probe. The potential power of recombinant DNA analysis in forensic science is discussed.  相似文献   

12.
本文介绍了利用型特异性沉淀素血清环状沉淀法检验人唾液斑、精液斑ABO血型的方法与实验结果,并与中和试验及解离试验进行了比较。实验结果表明,本法操作简便,对多种干扰条件下的唾液斑、精斑均具有高度的型特异性,并能从分泌液与血液的混合斑中准确地鉴别出分泌液的血型。本法仅需0.4cm的分泌斑纱线即可进行血型鉴定,其灵敏度高于中和试验而略低于热解离试验,并能有效地检出陈旧分泌液斑中的型物质,因此适于在实际检案中应用。  相似文献   

13.
Planimetric measurements were employed for reading the results of an elution test to determine Lewis blood groups in dry human bloodstains. In the absorption-elution test, two varieties of indicators were used to detect eluted Lewis antibodies. First, 64 blood-stains aged between 2 to 8 months were tested with glutaraldehyde (GLA)-treated erythrocytes (planimetric hemagglutination assay, PMHA). This method demonstrated that dry stains weighing approximately 0.4 mg (equivalent to 3 microliters of whole blood) were sufficient for detection of Lea or Leb antigen. Results were obtained within 1 h. Then, 37 of these stains were tested with Lewis substance-coated latex particles (planimetric latex agglutination assay, PMLA). The presence of Lea and Leb antigen were detected from dry stains weighing 0.1 mg (equivalent to 1 microL of whole blood) within 3 h. Both these assays are faster and simpler with accuracy than the enzyme-linked immunosorbent assay (ELISA). Latex particles coated with Lewis substance are, in particular, strongly agglutinated and show agglutination patterns more clearly than erythrocytes. The blind tests using these two methods properly classified 7 Le(a + b-) and 23 Le(a-b + ) bloodstains; whereas, 5 Le(a-b-) stains were undetermined by the criteria for these tests. These results indicate the usefulness of the PMHA and PMLA for typing Lewis blood groups from small bloodstains.  相似文献   

14.
本文应用国产两性电解质等电点聚焦法(PAGIEF)对1个月的40种动物血痕浸出液及经PCMB处理后的血痕浸出液的谱型进行了研究。根据谱型特征,成人除与人胎儿及猴难以鉴别外,与其它动物均可鉴别。动物间除鸟纲,鱼纲内有五组动物组内难以鉴别外,其它均能鉴别。经PCMB处理后,成人与人胎儿的谱型仍无差别,与其它动物的鉴别则更容易。结果表明,国产两性电解质用于等电聚焦进行血痕的种属鉴别是完全可能的。  相似文献   

15.
It was shown that the phenotypes of haptoglobin (Hg) can not be detected in stains of dried blood of salmon, roach and bream. The results of experimental research of blood of the above fish species are described according to the Cm system. It was proven as possible to identify the human blood in stains with admixtures of blood of the above fish by using the Hp and Cm systems.  相似文献   

16.
《Science & justice》2014,54(6):432-438
Current methods of detection and identification of blood stains rely largely on visual examination followed by presumptive tests such as Kastle–Meyer, Leuco-malachite green or luminol. Although these tests are useful, they can produce false positives and can also have a negative impact on subsequent DNA tests. A novel application of visible wavelength reflectance hyperspectral imaging has been used for the detection and positive identification of blood stains in a non contact and non destructive manner on a range of coloured substrates. The identification of blood staining was based on the unique visible absorption spectrum of haemoglobin between 400 and 500 nm. Images illustrating successful discrimination of blood stains from nine red substances are included. It has also been possible to distinguish between blood and approximately 40 other reddish stains. The technique was also successfully used to detect latent blood stains deposited on white filter paper at dilutions of up to 1 in 512 folds and on red tissue at dilutions of up to 1 in 32 folds. Finally, in a blind trial, the method successfully detected and identified a total of 9 blood stains on a red T-shirt.  相似文献   

17.
Forensic scientists may encounter blood spatter at a scene which may be pure or a mixture of fly artifacts and human bloodstains. It is important to be able to make an informed identification, or at least advanced documentation of such stains since the mechanics of production of fly artifacts are not determinable to the crime scene reconstructionist from regular police forces. We describe three cases in which experiments and crime scene reconstruction led to additional information. Case 1: Above the position of a victim, numerous blood stains of the low-high-velocity type were found. Exclusion of these stains being caused by force (but instead caused by the activity of adult blow flies) by use of the following observations that were confirmed in experiments: (a) sperm-/tadpole-like structure with length > width, (b) random directionality, and (c) mixture of round symmetrical and teardrop shaped stains. Case 2: A reddish spatter field was found on a fan chain two rooms away from the place where a dead woman was found. Localization of the spatter on the bottom end of the surface hinted strongly towards fly activity. Case 3: Double homicide; submillimeter stains were found on a lamp between the two corpses. Activity of flies was less likely compared to alternative scenario of moving lampshade and violent stabbing.  相似文献   

18.
Fluorat-02-3M liquid analyzer essentially extends the range of hemoglobin measurements, increasing its concentration in the studied extract from 0.1 to 100 micrograms in a 100 microliters sample (the lower threshold concentration remains unchanged: 0.005 in a 100-microliters sample) in detection of the blood in stains on material evidence pieces by fluorescent hemotest. This allows detection of blood in both washed and clearly seen blood stains on pieces of material evidence. Examples of using this method for measuring mass concentrations of zinc in water extracts on a Fluorat-02-3M analyzer are presented. The analyzer was developed at the Bureau of Forensic Medical Expert Evaluations of the Leningrad region for tentative detection of seminal fluid in stains on material evidence pieces. The results of this method are objectively recorded.  相似文献   

19.
A second collaborative exercise on RNA/DNA co-analysis for body fluid identification and STR profiling was organized by the European DNA Profiling Group (EDNAP). Six human blood stains, two blood dilution series (5-0.001 μl blood) and, optionally, bona fide or mock casework samples of human or non-human origin were analyzed by the participating laboratories using a RNA/DNA co-extraction or solely RNA extraction method. Two novel mRNA multiplexes were used for the identification of blood: a highly sensitive duplex (HBA, HBB) and a moderately sensitive pentaplex (ALAS2, CD3G, ANK1, SPTB and PBGD). The laboratories used different chemistries and instrumentation. All of the 18 participating laboratories were able to successfully isolate and detect mRNA in dried blood stains. Thirteen laboratories simultaneously extracted RNA and DNA from individual stains and were able to utilize mRNA profiling to confirm the presence of blood and to obtain autosomal STR profiles from the blood stain donors. The positive identification of blood and good quality DNA profiles were also obtained from old and compromised casework samples. The method proved to be reproducible and sensitive using different analysis strategies. The results of this collaborative exercise involving a RNA/DNA co-extraction strategy support the potential use of an mRNA based system for the identification of blood in forensic casework that is compatible with current DNA analysis methodology.  相似文献   

20.
作者用引物Y_3、Y_4和DNA聚合酶链式反应(PCR)作微量人类血液(痕)和毛根的性别鉴定。扩增的靶序列位于Y染色体DNA特异3.4kb重复序列中,扩增产物为460bp。检材用量为:新鲜血液0.5μl、血痕纱纤维1mm、毛根单个。20例保存4个月的血痕与2例保存6年半的血痕性别判定结果均正确,无性别记载的保存9~11年的3例血痕显现了清晰的460bpY特异DNA扩增带。15例保存20天的自然脱落毛根性别判定结果均正确。本法省略了检材处理中的酚-氯仿抽提DNA等纯化步骤,既简化了实验操作,又减少了检验过程中外源DNA的污染机会和样品DNA的损耗,使这一性别鉴定方法更符合法医学实践的需要。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号