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311.
人类基因组遗传多态现象研究的深入,导致了法科学领域个体识别和亲权鉴定发生根本性变化。本文就新的遗传标记和各种DNA鉴定技术在法科学中的研究进展、应用前景与亟待解决的问题进行了探讨。 Abstract:With the study advances on DNA polymorphism of human genome,radical changes have been taking place in forensic individual identification and paternity tests.In this paper,we introduced research progress of new genetic markers,their applications and problems should be solved urgently in the field of DNA-based identity test in forensic sciences.  相似文献   
312.
DMSO通常经验性地用于提高PCR扩增的效率,但是过量的DMSO可以显著降低特异序列的扩增效率,尤其是导致非特异性扩增的现象却被忽视.在6%的DMSO存在时,开始出现非特异条带,同时特异扩增产物减少.本文首次报道DMSO对PCR产物特异性的影响并确定了克服上述现象产生的途径,即通过增加模板-引物的比例消除非特异条带.而通常提高复性温度只能部分减少非特异产物,不能避免非特异扩增.本文结果有助于提高常规PCR,尤其是分子遗传学分析中经常使用的随机扩增多态性DNA(randomamplifiedpolymorphicDNA,RAPD)检测的准确度。 Abstract:DMSO is the most often empirically used to increase efficiency of PCR.However,it is ignored that DMSO can also decrease the amplification of specific sequences and result in non- specific amphfications.Non-specific bands are detected at 6% DMSO,as specific amplification declines.This is the first report about the effects of DMSO on the specificity of PCR and establishment of the method for avoiding non-specific products,which can be overcome by increasing template-primer ratio rather than annealing temperature.Our data will be of much help for random amphfied polymorphic DNA (RAPD) assays for molecular genetic analyses.  相似文献   
313.
用红霉素、头孢唑啉钠、头孢拉定、头孢霉素(国产和进口)等5种抗生素对农杆菌LBA4404进行抑菌试验,以头孢霉素的抑菌效果最好.头孢霉素作为抑菌剂用于大豆遗传转化试验时,在下胚轴浓度以300mg/L,在子叶节以500mg/L为宜.大豆品种对卡那霉素的反应在出愈率上表现相似,在褐化率上表现有些不同.大豆不同外植体对卡那霉素的反应存在较大差异,以真叶反应最敏感,下胚轴反应最迟钝.在以卡那霉素作为抗性选择标记时,选择压力真叶和子叶节以50~100mg,L为好,下胚轴以100~200mg/L为宜。 Ahstract:The experiment of inhibiting Agrobacterium LBA4404 was undertaken with 5 antibiotics (the Erythronycin Base,Cefazolin Sodium,Cefradine,2 kinds of Cefotaximes).Among them,Cefotaxime showed the best effect.When Cefotaxime is used in transformation,the ideal concentration is 300mg/L in hypocotyl and 500mg/L in cotyledon node.The response of soybean varieties to Kanamycin is similar in induction of callus rate and is different in brown rate of callus.Differences of the response of soybean explants to Kanamycin were found.The young leaves are sensitive to Kanamycin,but hypoeotyl is not.The ideal selecting pressure of Kanamycin is 50- l00mg/L in young leaf and cotyledon node,andl00-200mg/L in hypocotyl when Kanamycin is used as selection marker.  相似文献   
314.
本文对203名青少年白发患者的皮纹进行了分析,并与216名正常对照组个体作了比较.发现青少年白发组的As和Wd出现率以及A/A和L/W的对应频率均显著低于正常对照组;青少年白发组女性的a-bTRC值、男性变异型掌褶纹的出现率、10指同斗频率、右手Ⅰ2区及左手Hy区的花纹出现率均显著高于正常对照组的相应出现率.说明青少年白发者的皮纹可能有自身的遗传特征。 Abstract:This paper sought to analyze the dermatoglyph of 203 cases with juvenile poliosis,and make an individual contrast with the control group of 216 normal juveniles.It was found that the incidence of As and Wd in the group of juvenile poliosis and the correspondence rate of A/A and L/W were obviously lower than those of the normal contrast group,while a-b TRC value in the female patients with juvenile poliosis and the incidence of abnormal palmprint in the male, the frequency of all loop whorl,and palm patterns in the I2 area of the right hand and in the Hyarea of the left hand were evidently higher than the corresponding incidences of the normal contrast group.Dermatoglyph of the juvenile poliosis has its own heredity.  相似文献   
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317.
Autophagy is a major cellular pathway used to degrade long-lived proteins or organelles that may be damaged due to increased reactive oxygen species(ROS) generated by cellular stress. Autophagy typically enhances cell survival, but it may also act to promote cell death under certain conditions. The mechanism underlying this paradox, however, remains unclear. We showed that Tetrahymena cells exerted increased membranebound vacuoles characteristic of autophagy followed by autophagic cell death(referred to as cell death with autophagy) after exposure to hydrogen peroxide. Inhibition of autophagy by chloroquine or 3-methyladenine significantly augmented autophagic cell death induced by hydrogen peroxide. Blockage of the mitochondrial electron transport chain or starvation triggered activation of autophagy followed by cell death by inducing the production of ROS due to the loss of mitochondrial membrane potential. This indicated a regulatory role of mitochondrial ROS in programming autophagy and autophagic cell death in Tetrahymena. Importantly, suppression of autophagy enhanced autophagic cell death in Tetrahymena in response to elevated ROS production from starvation, and this was reversed by antioxidants. Therefore, our results suggest that autophagy was activated upon oxidative stress to prevent the initiation of autophagic cell death in Tetrahymena until the accumulation of ROS passed the point of no return, leading to delayed cell death in Tetrahymena.  相似文献   
318.
One juvenile and one adult female wolf snake(Colubridae: Lycodon) were sampled at Yixian and Fuxi, Huangshan, Anhui, China in the summer of 2011 and 2012, respectively. The two specimens were identified as Lycodon liuchengchaoi based on external morphology and molecular data. This is a new reptile record in Anhui Province. In our laboratory, four eggs were laid and three neonates were hatched successfully. This is the first record of the laying and incubation of L. liuchengchaoi eggs. The five specimens were deposited at the Museum of Huangshan University(HUM20140001) and Guangdong Entomological Institute(HB-lcfsp12613, HB-lcfsp-ch1~3).  相似文献   
319.
栓菌漆酶在毕赤酵母中高效表达及重组酶的性质   总被引:1,自引:0,他引:1  
栓菌420(Trametes sp.420)漆酶基因lacD以两种方式在巴斯德毕赤酵母(Pichia pastoris)进行异源表达,产生两种重组漆酶:rLacDx(具有天然N-末端)和rLacDe(N-末端带有8个额外的氨基酸残基)。摇瓶发酵18d,rLacDx和rLacDe的产量分别为1.21×105u/L、7.38×104u/L[以2,2′-连氮-3-乙苯-二噻唑-6磺酸(ABTS)为底物]。在高密度发酵条件下,rLacDx的产量增加到2.39×105u/L,同时其生产周期降至7.5d。两种重组酶对愈创木酚底物的氧化特性相似,且在50℃和pH3~10的范围内均稳定。然而,rLacDx对底物ABTS的比活力(1761u/mg)高于rLacDe(1122u/mg),其表观Km值(427μmol/L)低于rLacDe(604μmol/L)。  相似文献   
320.
To evaluate the immunogenicity of inactivated SARS coronavirus(SARS-CoV),three groups of rabbits were immunized three times at 2-week intervals with inactivated vaccine + adjuvant,adjuvant,and normal saline respectively.Eight batchs of serum were sampled from the auricular vein at day 7 to day 51,and specific IgG antibody titers and neutralizing antibody titers were detected by indirect ELISA and micro-cytopathic effect neutralizing test.Antibody specificity was identified by proteinchip assay.Histopathological changes were detected by H&E staining.The results showed that,rabbits in the experimental group immunized with inactivated SARS-CoV all generated specific IgG antibodies with neutralizing activity,which suggested the inactivated SARS-CoV could preserve its antigenicity well and elicit an effective humoral immune responses.The peak titer value of specific IgG antibody and neutralizing antibody reached 1:40960 and 1:2560 respectively.In the experimental group,no obvious histopathological changes was detected in the H&E stained slides of heart,spleen,kidney and testis samples,but the livers had slight histopathological changes,and the lungs presented remarkable histopathological changes.These findings are of importance for SARS-CoV inactivated vaccine development.  相似文献   
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