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21.
用过氧化物酶原位复性电泳(SDS-POD-PAGE)技术分析了部分肝切除(partial hepatectomy,PH)、部分肝切除后再热激(partial hepatectomyfollowing heat shock,PH-HS)和先热激再部分肝切除(heat shock follow ing partial hepatectomy,HS-PH)后肝再生期间过氧化物酶(POD)基因表达差异,结果表明,PH中表达的POD基因种类(7个)>PH-HS(5个)>HS-PH(3个);三个模型的POD总活性为:HS-PH>PH>PH-HS.根据实验结果推测,POD在肝再生和肝损伤恢复中起一定作用。 Abstract:Expression difference of the peroxidase(POD)genes during liver regeneration after partial hepatectomy(PH),partial hepatectomy following heat shock(PH-HS)and heat shock following partial hepatectomy(HS-PH)was analyzed by POD renatured electrophoresis(SDS-POD-PAGE).The results showed that the expressed POD gene kinds in PH,PH-HS and HS-PH were 7,5 and 3 respectively,and that the total activities of POD in the three models were HS-PH>PH>PH-HS.The results suggested that POD play some roles during liver regeneration and in recovery after liver damage.  相似文献   
22.
应用外周血淋巴细胞染色体畸变和CB微核分析方法,对2000年河南许昌“3.06”60Co辐射事故1例受照者(A)和2000年河南开封“6.26”辐射事故一例过量放射性核素内污染致γ射线照射受照者(B)的生物剂量进行估算。结果表明,“A”和“B”两例受照者依据双+环率估算的剂量分别为1.44Gy和0.15Gy,CB微核率估算的剂量分别为1.43Gy和0.22Gy,与用物理方法估算的剂量比较接近,亦与放射损伤的临床诊断一致。泊松分布检验证实,“A”偏离泊松分布,受到不均匀照射。提示染色体畸变和CB微核分析是非常可靠的生物计量估算方法。 Abstract:Biological doses were estimated by using the yields of dicentrics plus rings(dic+r) and cytokinesis-block micronuclei (CBMN) for two victims of the accident radiation occurred on Mar 6,2000 in the City of Xuchang(victim A),and Jun 26,2000 in the City of Kaifeng(victim B),Henan Province,respectively.The results indicated that the equvalent whole body doses based on the standard dose-response curves established by the analyses of dic+r and CBMN were estimated to be 1.44Gy and 1.43Gy(victim A),and 0.15Gy and 0.22Gy(victim B).These doses were very consistent with the mean doses calculated from physical measurement and conformable to the clinical dianosis.The dic+r aberrations of victim A did not accord with Poisson distribution.The analyses of chromosomal aberrations and CBMN are an extremely reliable method in biological dosimetry.The radiation which victim A was exposed to was heterogeneous.  相似文献   
23.
小麦干尖叶是近年在小麦育种中所发现的一种叶部坏死性状,直接影响小麦的产量。本文以具有干尖叶与正常叶这一相对性状的部分小麦品种(系)为基本材料,采用正反杂交、正反回交及杂种后代分析和异源细胞质替换,首次对干尖叶的遗传及性状传递规律进行了研究。结果表明:干尖叶性状与一般杂种坏死与黄化截然不同, 并非仅杂种所具有,能作为纯系稳定遗传; 其表型受核内一对主效显性基因所控制,即使采用异源细胞质替换, 以特定质核互作也难以克服这一性状的对外表达,只有通过杂交与后代选择,纯化与稳定隐性正常叶方可克服。 Abstract:In this paper,the inheritance and transmission law of the character for wheat leaf-tip necrosis were firstly investigated with the contrasting character of leaf-tip necrosis and normal leaf in wheat varieties for basic test materials by reciprocal crosses and backcrosses,hybrid progeny analysis and aliencytoplasm substitution.The results indicated that the wheat leaf-tip necrosis is abviously different from the hybrid necrosis and hybrid chlorosis.It is not only expressed in hybrid but also stable inheritance as pureline.Its phenotype is conditioned by a pair major dominant gene.It is not overcome even if special interaction of nucleus-cytoplasm after alien cytoplasm substitution.Only be the varieties or lines with normal leaf obtained by crossing and selecting stable normal leaf character with recessive gene.  相似文献   
24.
在较长的时间内,可保持正常生理状态与细胞活性的原生质体的制备及保存技术是进行空间细胞融合实验的前提条件。本研究以0.7ml/L的葡萄糖作渗透压,在6-8℃低温条件下经过72小时保存后,供试原生质体的存活率仍可达81%,并保持了其长壁与分裂的特性。 Abstract:Storage duration and acativity of isolated protoplasts are important problem for experiment on plant cell fusion in space.We have achieved preliminary success using glucose as osmotic reagent,The survival protopasts after 72 hour storage in 0.7mol/L glucose at 6~8℃ reached 81% and maintained a very high activity of division.  相似文献   
25.
对家猪不同品种及家系间的染色体组型、C-带、Ag-NORs多态性进行的研究表明:杜洛克猪、约克夏猪、长白猪体细胞染色体数2n=38,核型2n=10sm+12m+4st+12t, 而13/17易位纯合子猪(36, rob. 13/17)的体细胞染色体数2n=36,核型2n=10sm+12m+6st+8t; 13/17易位杂合子猪(37,rob. 13/17)的体细胞染色体数目为 2n=37,核型为2n=10sm+12m+5st+10t。5种家猪的C-带在13~18号染色体上存在大、中、小三种类型, 且呈多态性分布。杜洛克猪、约克夏猪、长白猪、13/17易位纯合子猪、13/17易位杂合子猪的Ag-NORs均数分别为2.05、2.06、2.00、1.99、1.98,说明Ag-NORs在品种、个体及细胞间具有多态性。 Abstract:The present experiment is carried out to make comparative stdy on polymorphism of chromosome Karyotypes, C-band ?and Ag-NORs of different breeds and strains in domestic Pigs. The results showed that the chromosome number of somatic cell in Duroc, Yorkshire and Landrace Pig Was 38 and the karyotype was 2n=10sm+12m+4st+12t. But in heterozygous Rob 13/17(37, rob. 13/17) Pig, the chromosome number of somatic cell was 37 andthe karyotype was 2n=10sm+12m+5st+10t, while in homozygousRob 13/17(36, rob. 13/17) Pig, the somatic cell chromosome number was 36 and the karyotype was 2n=10sm+12m+6st+8t. It was also showed that there were three C-band types in size on chromosome No. 13-18 showing polymorphism in three breeds and two strains of domestic Pigs. The average of Ag-NORs in Duroc, yorkshire,Landrace, homozygous Rob. 13/17 and heterozygous Rob. 13/17 Pig was 2.05, 2.06, 2.00, 1.99 and 1.98, respectively. It is suggested that Ag-NORs have polymorphism among strains, which can be used as a genetic index to analyse relationships among domestic animals with high reliability.  相似文献   
26.
根据与水稻抗白叶枯病基因Xa-4紧密连锁的分子标记M55的序列设计引物,通过对国际水稻研究所育成的抗白叶枯病近等基因系和基因累加系的叶片DNA、半粒种子提取物及Xa-4基因的杂合体DNA的PCR特异扩增,初步建立了Xa-4的PCR标记体系。进而用该标记体系对我国籼型杂交水稻常用的亲本材料进行分析,揭示出了Xa-4在这些材料中的分布情况。 Abstract Based on the sequence of a DNA marker tightly linked to the rice bacterial blight(BB) resistance gene Xa-4, two primers were designated and synthesized to develop a PCR marker for the gene. Specific amplified polymorphism analysis was carried out with these primers on a set of BB resistance isogenic lines and pyramided lines developed by IRRI. Two PCR bands were revealed corresponding to lines with dominant Xa-4 and those with the recessive allele, respectively, regardless the lines pyramided with other resistance genes. A hybrid with heterozygous Xa-4 produced both of the two allele PCR pattern. Then, the PCR marker was used to survey a range of hybrid rice germplasm. The results of the germplasm survey will be useful in hybrid rice breeding programs aimed at exploiting Xa-4.  相似文献   
27.
人类指掌皮肤嵴纹与智力发育的相关性研究   总被引:6,自引:1,他引:5  
本工作对120例遗传型智残者和60例非遗传型智残者的指、掌皮肤嵴纹数进行分析,并分别与相同例数的对照组同类资料进行比较,找出与智力发育相关的指端、指间区、指基部皮纹参数,据此将遗传型智残组按智商值的不同分为6个组,将不同智商组对应的各区嵴纹数进行分析处理。结果表明,指端皮肤嵴纹数与智商呈正相关,相关系数r=0.8319,各指间区和指基部嵴纹数与智商值呈负相关,相关系数r=-0.7392。 Abstract Digital and palmar of 120 cases of hereditary mental deficiency and 60 cases of non-hereditary mental deficiency were analysed, and compared with the control group using the same cases and identical data, and then skin vein parameter interrelated with intelligence development for digital end, interdigital area, digital root were found. In the light of this we divided the hereditary mental deficiency group into 6 accorcding to IQ value, and analysed statistically every area ridge count corresponding to different IQ group. The result showed that ridge count of digital end was positively correlated with IQ value correlative coefficientr=0.8319; Whereas ridge count of interdigital area and digital root were negatively correlated with IQ value correlative cofficientr=0.7392.  相似文献   
28.
肠道微生物与寄主具有复杂的、多方面的相互依存效应,这种依存效应所产生的共生关系或协同进化关系既可反映寄主间的系统演化关系,也可显示肠道微生物间的系统演化关系,共生关系或协同进化关系是由于寄主与肠道微生物两者之间存在着相互自然选择作用所形成的,在长期的进化历程中逐步发生的共生关系信息很可能被记录在DNA序列中。本文通过检测鲤鱼科8种鱼中9种肠道菌群的分布含量对这9种菌群进行分析,且利用从GenBank调取这9种肠道细菌菌属的43个种或亚种的16S DNA序列的构建NJ树和MP树,将这6个科9个属43个种或亚种分为革兰氏阴性和革兰氏阳性两大类群(一级分枝)。在这两类群中,又以科为单位分为6个亚类群(二级分枝),而肠杆菌科中则以属为单位分为4个小类群(三级分枝),此外球状菌与杆状菌也能截然分开。将16S DNA的NJ树隐去所有的种,以属为单位所得到的以分枝形式的无根树在拓扑结构上与菌群分布含量(寄主范围)所构建的无根树相近,但芽孢杆菌在两种无根树的位置中有较大的差异。如果提高检测水平,扩大所检测的寄主对象,这种差异有可能消除。 Abstract:There is a complex- and multi-effect for interdependent survival between intestinal- microorganisms and hosts.The symbiosis or coevolution that results from this effect for interdependent survival is used to reveal the phylogenies of hosts as well as intestinal microorganisms.The symbiosis or coevolution between intestinal microorganisms and hosts has been generated by interactive natural selection occurred between them.The symbiosis information that has been formed by interactive natural selection during a long evolutionary process must be recorded in DNA sequences.According to this point of view,we analyzed the phylogeny of 9 intestinal bacteria genera using their contents in intestines of 8 Cyrinidate species.At the same time,we fetched the 16S rRNA gene DNA sequences of 43 intestinal bacteria species being included in these nine genera of six intestinal families from GeneBank and constructed phylogenetic trees by NJ and MP methods.The NJ tree and MP tree have the same topologic configuration and are identical with the classical phylogenetic tree.Both the trees of 16S rRNA gene separated 43 bacteria species into gram-negative bacteria group and the gram-positive bacteria group,which are the first branches.Each of the first branches (groups) made again 6 subbranches (subgroups) where each subbranch is a family.Especially,the subbranch (subgroup) of enterobacteriaceace made again four small branches as genus taxon.This tree also shows that bacilliform bacterium is distinct from each other in the NJ and MP trees.After all species on the tree are merged,the topological configuration of the unrooted tree of 16S gene is closed to that of the host range unrooted tree.However,the position of bacillus is greatly changed on both the unrooted trees.The difference can be found if we increase the examination level and extend the hosts examed.  相似文献   
29.
Jk (kidd) blood group antigens are carried by the urea transporter UT-B[1,2]. The Jknull phenotype, lack-ing urea permeability in erythrocytes[3,4], has a very low frequency in all populations except Polynesians and Finns[5]. In Japan, only 14 individuals with Jk (a-b-) phenotype were identified from 638460 screened donor’s blood samples using the 2 mol/L urea solution hemolysis test[6]. The frequency of Jknull is 0.27% in Polynesian, about 0.03% in Finland[7], and extremely rare in Fran…  相似文献   
30.
Copyright by Science in China Press 2005 Primary hepatocarcinoma is one of the most fre-quent digestive-tract cancers, particularly in China. The incidence and death rate of primary hepatocarci-noma in China is the highest in the world, with about 1100 thousands people dying from primary hepatocar-cinoma per year[1]. Although the chemotherapeutic agents are the main therapeutic approach for hepato- carcinoma, they are relatively ineffective and result in many toxic and side effects. Accordin…  相似文献   
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