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631.
目的为了获得引物3'端存在SNP点突变的插入缺失遗传标记rs10644346所有等位基因片段。方法基于等位基因特异性PCR原理,设计一条共用上游引物,二条3’端倒数第二个位置特异性碱基的下游引物。运用该三条引物检测150个无关个体及10例亲子关系已确定的三联体,同时运用其中二条引物(共同上游引物和其中一条下游引物)扩增9例样本。结果三条引物扩增150个无关个体均有清晰扩增片段;10例三联体案例亲代与子代扩增片段均符合孟德尔遗传定律;二条引物扩增9例样本后发现特定片段丢失。结论本次研究设计的三条引物PCR,证明特异性碱基位置除了通常的3'末端,理想条件下3'端的其他位置(如倒数第二个位置)也可以成为有效选择,该三条引物设计方法为检测引物侧翼存在点突变的遗传标记提供了一种新的参考。  相似文献   
632.
目的为了探讨云南汉族人群糖皮质激素受体基因(NR3C1)多态性与攻击行为的相关性。方法应用改良多重高温连接酶反应(improve multiplex ligasedetection reaction,iMLDR)技术检测194例云南汉族有攻击行为的监狱服刑人员和301例健康对照样本的NR3C1基因SNPs(rs6190、rs6191、rs6198、rs41423247、rs56149945)基因型,采用SPSS19.0软件、PHASE2.1平台进行统计学分析。结果 rs6191和rs41423247单个基因座的等位基因分布在非攻击组与攻击组、抢劫亚组和故意伤害亚组中均无显著性差异;rs41423247的基因型在非攻击组与抢劫亚组中的分布有显著性差异(p=0.048);构建的4种单倍型分布在非攻击组与攻击组、抢劫亚组和故意伤害亚组中均无显著性差异。结论云南汉族人群NR3C1基因的rs41423247基因座的单基因座多态性可能与指向他人的躯体攻击行为相关,rs6191基因座的单基因座多态性可能与暴力攻击行为无关。  相似文献   
633.
The cis and trans isomers of 3‐methylfentanyl and its three analogs were chemically synthesized, and these compounds were characterized and differentiated by gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), and nuclear magnetic resonance (NMR) spectroscopy. The cis and trans isomers of the 3‐methylfentanyl analogs were completely separated by GC/MS. Although the high temperature of the GC injection port caused thermal degradation of β‐hydroxy‐3‐methylfentanyl, the degradation was completely suppressed by trimethylsilyl derivatization. The isomers were also well separated by LC/MS on an octadecylsilyl column with 10 mM ammonium acetate and methanol as the mobile phase. The proton NMR signals were split when the hydrochloride salts of the 3‐methylfentanyl analogs were dissolved in deuterated chloroform because stereoisomers were formed by the coordination of the hydrochloride proton to the nitrogen of the piperidine ring of the 3‐methylfentanyl analogs.  相似文献   
634.
Loeys–Dietz syndrome is a recently described autosomal dominant disorder with underlying vasculopathy characterized by aortic and other vascular aneurysmal dissection/rupture. A 61‐year‐old man is reported who died suddenly and unexpectedly and at autopsy was found to have a ruptured abdominal aortic aneurysm. Additional findings included dolichostenomelia, high‐arched palate, and pectus excavatum. There was a strong family history of Loeys–Dietz syndrome, although the decedent had never been tested. Death was, therefore, due to a ruptured abdominal aortic aneurysm in a case of probable Loeys–Dietz syndrome. Although Loeys–Dietz syndrome shares common characteristics with Marfan and other connective tissue syndromes, it is a distinct entity with a much more aggressive clinical course. Lethal events may not occur until later adult life; however, the identification of the syndrome and differentiation from other connective tissue disorders at autopsy is important so that genetic investigation of close relatives can be undertaken with prophylactic surgical treatment if necessary.  相似文献   
635.
The diagnosis of death as a result of starvation is established on anthropological measurements, visual appearance of the deceased on external and internal examination, microscopic analysis, laboratory testing, and exclusion of other causes of death. Herein, we present our findings on a case of 95‐year‐old man who died of starvation. After the diagnosis of starvation was established by traditional forensic medicine methods, we have conducted retrospective segmental analysis of stable carbon (δ13C) and nitrogen (δ15N) isotope ratios in hair sample. This method reveals periods of starvation through decrease in δ13C and increase in δ15N along the strand of hair. Our analysis revealed the decrease of 0.6 ‰ in δ13C during the last 10–12 weeks prior to death, similar as reported in other investigations. Also, a decrease of 0.7 ‰ in δ15N during the last 8–10 weeks prior to death was determined that was different than observed in previous studies.  相似文献   
636.
There are specific challenges related to forensic dental radiology and difficulties in aligning X‐ray equipment to teeth of interest. Researchers used 3D printing to create a new device, the combined holding and aiming device (CHAD), to address the positioning limitations of current dental X‐ray devices. Participants (N = 24) used the CHAD, soft dental wax, and a modified external aiming device (MEAD) to determine device preference, radiographer's efficiency, and technique errors. Each participant exposed six X‐rays per device for a total of 432 X‐rays scored. A significant difference was found at the 0.05 level between the three devices (p = 0.0015), with the MEAD having the least amount of total errors and soft dental wax taking the least amount of time. Total errors were highest when participants used soft dental wax—both the MEAD and the CHAD performed best overall. Further research in forensic dental radiology and use of holding devices is needed.  相似文献   
637.
本文探讨了SMTP协议和POP3协议的工作原理和工作过程以及通过SMTP协议利用VB的WinSock从控件发送电子邮件的客户端程序的编写步骤。  相似文献   
638.
党的第三代中央领导集体的马克思主义观,经历了一个确立、成熟和深入发展的阶段.从发生论、本质论、结构论、特征论和价值论等方面回答了什么是马克思主义的问题;从认真地学习和研究、完整准确地理解、既坚持又发展、不断进行理论创新、理论联系实际等方面说明了怎样对待马克思主义的问题.这一科学的马克思主义观具有重要的理论价值和实践意义.  相似文献   
639.
Over the past decade, the human identity testing community has settled on a set of core short tandem repeat (STR) loci that are widely used for DNA typing applications. A variety of commercial kits enable robust amplification of these core STR loci. A brief history is presented regarding the selection of core autosomal and Y-chromosomal STR markers. The physical location of each STR locus in the human genome is delineated and allele ranges and variants observed in human populations are summarized as are mutation rates observed from parentage testing. Internet resources for additional information on core STR loci are reviewed. Additional topics are also discussed, including potential linkage of STR loci to genetic disease-causing genes, probabilistic predictions of sample ethnicity, and desirable characteristics for additional STR loci that may be added in the future to the current core loci. These core STR loci, which form the basis for DNA databases worldwide, will continue to play an important role in forensic science for many years to come.  相似文献   
640.
There is currently no accurate method to identify vaginal epithelial cells uniquely. This study aimed to use a cell extraction procedure compatible with routine forensic sampling methods, and to investigate the expression of cytokeratin (CK), estrogen receptor-alpha (ERalpha), and phosphodiesterase 5 (PDE5) in order to distinguish between skin, buccal, vaginal, and external penile epithelial cells. Seminal fluid samples were also examined. Epithelial cell samples were fixed in formalin, embedded in agarose, and processed using histological methods. Antigen-antibody reactions were detected using the DAKO Envision+ detection system. CK was present in all cells from all five sources confirming the origin of cells as epithelial. Both ERalpha and PDE5 positively labeled vaginal, buccal, and skin epithelial cells. Although an antigen unique to vaginal epithelial cells was not identified, we have described a cell extraction procedure for use in the immunohistochemical detection of a wide range of antigens, an approach compatible with forensic diagnostics.  相似文献   
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