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61.
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   
62.
云南地方猪种血液蛋白多态性研究   总被引:4,自引:0,他引:4  
采用蛋白电泳技术研究了云南地方猪种血液蛋白多态性。共分析了3个云南地方猪种32-36个遗传位点,其中AKP、CAT、DIA、ES、G6PD、PA、6PGD、PHI、TF等9个 位点检测到多态性,多态位点百分比为0.1875-0.2121,平均杂合度为0.0712-0.1027。结果表明,云南地方猪种血液蛋白多态程度较高,反映在蛋白水平上的遗传多样性较为丰富。 Abstract:In this paper,protein electrophoresis was used to analyze the blood protein polymorphism in Yunnan local pig breeds and 32~36 genetic loci in the Yunnan local pig breeds were surveyed,Nine of them,such as AKP、CAT、DIA、ES、G6PD、PA、6PGD、PHI and TF,were found to be polymorphic,the mean heterozygosit(H)was 0.0712~0.1027.The results indicated that the blood protein polymorphism in the Yunnan local pig breeds is high,the Yunnan local pig breeds are wealthy in genetic diversity in point of their protein level.  相似文献   
63.
家禽(鹅、鸭、鸡)血清酯酶多态性比较血型学初步研究   总被引:9,自引:2,他引:7  
鸡的酯酶在两个区域出现了变异, 靠近阳极的Es-1区共有3条带,表现出7种表型组合(AA、 BB、CC、AB、AC、BC和无带O型),分别受控于常染色体上相同基因座位上3个复等位基因(Es-1^A|、Es-1^B|、Es-1^C|)和1个隐性基因(Es-1^O|)。在原点和Es-1之间的Es-2区表现出有带(+)和无带(-)两种类型。鹅的血清酯酶与鸡截然不同。在鸡的Es-2区域,鹅的带谱信号弱(无)。在与鸡Es-1区域相应位置,鹅存在着8-9条谱带,其中的1号、2 -7号存在着个体水平的多态现象。鸭血清酯酶的聚丙烯酰胺谱带与鹅非常相似。鹅、鸭血清酯酶的遗传机制有待交配实验确定。  相似文献   
64.
利用聚合酶链反应和荧光(6-FAM)自动化检测技术对广东地区汉族106例无亲缘关系样本进行MICA基因外显子5和MICB基因内含子1微卫星基因座多态性及其单体型分布调查。根据群体资料估算两者间的单体型频率、连锁不平衡参数、相对连锁不平衡参数。结果显示,广州地区汉族人群MICA和MICB微卫星基因座基因型分布符合Hardy-Weinberg平衡法则,共检出MICA微卫星基因座 5个等位基因, MICB微卫星基因座14个等位基因。其中MICA A5基因频率最高(0.2877),A4基因频率最低(0.1321)。MICB CA14等位基因频率最高(0.3255),CA19、CA28等位基因频率最低(0.0047),未检出CA27。21种MICA-MICB单体型频率大于1%(连锁不平衡参数>0), 其中单体型A5-CA14 (16.73%), A5.1-CA18 (8.75%), A4-CA26(3.76%),A9-CA15(3.66%)和A6-CA21(2.61%)为强连锁常见单体型(χ2>3.84, P<0.05)。广州地区汉族人群MICA和MICB微卫星基因座多态性和单体型分布有其自身特点,MICA和MICB微卫星基因座适合做为遗传标志,用于人类学、遗传疾病基因连锁分析、法医学亲子鉴定和个体识别等研究领域。Abstract: This study is to investigate genetic polymorphisms and haplotypes of microsatellite locus in the exon 5 of the MICA gene and intron 1 of the MICB gene based on 106 samples of Guangzhou Han Population by polymerase chain reaction and fluorescent technique (6-FAM). The corresponding haplotype frequencies, linkage disequilibria values and relative linkage disequilibria values were estimated based on population data. The results show that the genotype distributions of MICA and MICB microsatellite meet Hardy-Weinberg equilibrium in Guangdong Han population. In total, 5 alleles of MICA microsatellite locus and 14 alleles of MICB microsatellite locus were observed. MICA A5 was the most common allele (0.2877), whereas A4 was the least popular one (0.1321). MICB CA14 was the most common allele (0.3255), and CA19 and CA28 were the least popular ones (0.0047). CA27 was not observed. Twenty-one kinds of MICA-MICB haplotypes occurred at frequencies of more than 1% (linkage disequilibria value>0). The common MICA-MICB haplotypes were A5-CA14(16.73%), A5.1- CA18 (8.75%), A4- CA26(3.76%),A9-CA15(3.66%) and A6-CA21(2.61%)(χ2>3.84, P<0.05), and they were strong linkage disequilibria. The polymorphisms and haplotypes distributions of MICA and MICB microsatellite locus in Guangzhou Han population have their own genetic characteristics. The microsatellite locus of the exon5 of the MICA gene and intron 1 of the MICB gene could be used as the genetic markers in the studies of anthropology, linkage analysis of genetic disease genes, individual identification and paternity test in forensic medicine.  相似文献   
65.
采用原代培养和传代培养法, 对1头毛冠鹿的胚肺组织细胞进行观察,发现一种新的核型,其二倍体染色体数目为2n=48,核型公式为2M+2ST+42T+XX,出现1对大的末端着丝粒染色体,C-带显示该染色体与已报道的相关染色体同源,首次提出毛冠鹿B染色体多态,对其传递机制进行了探讨。 Abstract: Primary culture and subculture were adopted using lung cells of a female Elaphodus cephalophus' embryo. A new karyotype and a pair of big telocentric chromosomes were found. The diploid has 48 chromosomes, and the karyotype formula is 2M+2ST+42T+XX. C-banding analysis shows that these chromosomes are homologous with those reported relevant chromosomes. This article is the first to report the polymorphism of Elophodus cephalophus B-chromosomes and studies it's transmitted mechanism.  相似文献   
66.
采用代表性差异分析法(RDA)研究了银额果蝇两个单雌系AKM46(含B染色体)和AGZ2(不含B染色体)两基因组间的差异。用AKM46作检测(tester)扩增子,AGZ2作驱赶(driver)扩增子,通过三轮消减杂交后,获得了6个差异片段(100bp~300bp)。亚克隆后,对11个片段测序并与GenBank数据库进行同源性比较分析,获得了9个新的序列。选择clone22 及clone42进行Southern杂交分析,这两个片段仅在检测扩增子及第一、第二、第三轮差异片段中检测到杂交信号,而在驱赶扩增子检测不到杂交信号。证实了这两个片段来自含有B染色体的单雌系AKM46,而且可能是B染色体上的特异基因片段。 Abstract:The genomic difference betweenDrosophila albomicanAKM46 (with B chromosome) and AGZ2 (without B chromosome) was analyzed by RDA (Representational Difference Analysis) technique. In RDA system, the tester amplicon is AKM46 while the driver amplicon from AGZ2. After three rounds of subtractive hybridization, six different products were obtained and identified, and their size was about 100bp~300bp. After subcloning, eleven positive clones were sequenced and blasted with Genbank database. Nine sequences were unmatched with the known sequences. Clone22 and clone42 were selected for Southern hybridization, and positive signals were observed only in tester amplicon, and the first, second, third differente products, not in driver amplicon. The results suggest that the sequence come from AKM46 and might be the specific genes in B chromosome.  相似文献   
67.
本文以微铺展技术制备中华鳖精母细胞联会复合体标本,经硝酸银染色后电镜观察,分析了SC组型。并与有丝分裂染色体组型相比较,发现二者有着良好的一致性,而且微小染色体的SC结构和着丝粒清晰,未发现形态上有分化的性染色体。中华鳖SC的研究为其细胞遗传学及性别决定机制提供了重要的依据。 Abstract Synaptonemal Complexes (SC) in Trionyx sinensis spermatocytes prepared with micro-spreading technique and silver staining was analyzed by electron microscopy. The meiotic SC karyotype was constructed from 10 cells and compared with mitotic chromosome karyotype. There is a good agreement between them. The structure and kinetochores of micro-chromosomes are very distinctive on each SC. There does not exist differential sex chromosome.  相似文献   
68.
21三体是人类最常见的先天性疾病,约95%患儿的超数21号染色体来源于母亲,且随母龄增加患儿出生率也随之增加。本文首次运用胞质分裂阻滞法(CB法)对不同年龄女性体细胞进行荧光原位杂交,对其21号染色体的分离情况进行分析。结果表明,随年龄的增加,女性体细胞中21号染色体不分离也随之增加,但21号染色体丢失无年龄效应, 且21号染色体不分离频率远高于其丢失。该结果表明,女性体细胞中21号染色体不分离与生殖细胞同样存在年龄效应。 Abstract  Trisomy 21 is the most common genetic desease in human. More than 90% is derived from mother. With the advancing of mother's age, the frequency of trisomy 21 is increasing. We detected the relation between chromosome 21 missegregation and age in cytokinesis-blocked female lymphocytes by in situ hybridization with chromosome 21 specfic probe. We have found that the age effect also exists in female somatic cells as in gamets.  相似文献   
69.
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   
70.
Objective: To study the treatmaient of non-small cell lung cancer, we established the HU-Prim allograft transplantation tumor model. Methods: The fresh tumor samples were transplanted in the right scapular subcutaneous layer of the severe combined immunodeficient Non-obese diabetic/severe combined immunodeficient(NOD/SCID) mice. The pathological features of the tumors were observed. Nonnecrotic tissue was inoculated subcutaneously into the right axillary. When the tumor in burdened rat grew approximately 100 mm3, according to the tumor size all the animals were divided into the following four groups, eight rats in each group: solvent control group, gefitinib group(100 mg/kg), erlotinib group(50 mg/kg), afatinib group(20 mg/kg). Aniamals were treated with drugs by intragastric(i.g.) administrated, once daily, for consecutively 14 days. Measure the tumor size 2-3 times every week. Results: Hu Prime1-NSCLC mutant sensitive xenograft model research data showed that reversible tyrosine kinase inhibitors gefitinib, erlotinib and irreversible tyrosine kinase inhibitor afatinib could effectively inhibit tumor growth in EGFR positive NSCLC allografts model. The pharmacodynamic activity of irreversible inhibitor was better than that of the reversible inhibitor. Specimens from clinical anthropogenic tumor retain characteristics of the human primary malignancy, histopathology, biological characteristics, and tumor markers, etc., which can more accurately reflect the characteristics of the tumor and the impact of interventions. Conclusion: The model is not only a good antitumor drug experimental platform, but also a new evaluation tool of individualized medication.  相似文献   
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