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41.
S. N. Novikov G. A. Churakov A. A. Philimonenko I. I. Ermakova E. M. Fedorova I. A. Burkot 《Russian Journal of Developmental Biology》2009,40(4):204-211
We investigated the specific pattern of major urinary proteins (MUPs) expression in 3-, 4-, and 12-week old mice of CBA/LacY and C57BL/6JY inbred strains using polyacrylamide gel electrophoresis. Quantitative evaluation of 8 protein fractions A-H with regard to sex, age, and genotype of the animals is presented for the first time. Actual problems of genetic control and neuroendocrine regulation of MUPs expression during ontogenesis are discussed. In the light of current views on MUPs as a key component in intrapopulation information exchange via pheromones, we put forward the idea that the genetically determined structure of the olfactory code of the definitive type is formed at an early ontogenetic stage on the basis of the MUPs combinatorial pattern. 相似文献
42.
Pil-Soo Seo Sun-Yeon Heo Eun Jong Han Jeong-Woo Seo Shin-Je Ghim Chul Ho Kim 《Biotechnology and Bioprocess Engineering》2009,14(2):168-174
The human papillomavirus (HPV) 18 L1 gene, which encodes the L1 major capsid protein, was isolated from a female patient in
Pusan, Korea Republic and was cloned into pGEX-4T-1 vector. The HPV-18L1 gene was expressed in Escherichia coli as a fusion protein with a glutathione-S-transferase (GST) tag. The soluble recombinant fusion protein, GST-18 L1 fusion,
was isolated to high purity. HPV-18 L1 was purified from the GST-18 L1 fusant after biotinylated thrombin cleavage, and then
the treated thrombin was removed serially using streptavidin conjugated resin. The purified HPV-18 L1 was confirmed by western
blotting using a rabbit anti-denatured papillomavirus polyclonal antibody. The virus-like particles (VLP) from the purified
full-length 18 L1 protein without any extra amino acid sequences was observed through the analysis of the electron microscope.
This is the first study to report the expression and purification of HPV-18 L1 in E. coli. This expression and purification system offers a simple method of expressing and purifying HPV L1 protein, and could potentially
be an effective route for the development and manufacturing of highly purified HPV-18 L1-based cervical cancer vaccines. 相似文献
43.
Adisak Tantiworawit Sujaree Khemakapasiddhi Thanawat Rattanathammethee Sasinee Hantrakool Chatree Chai-Adisaksopha Ekarat Rattarittamrong Lalita Norasetthada Pimlak Charoenkwan Somdet Srichairatanakool Kanda Fanhchaksai 《Bioscience reports》2021,41(2)
Hepcidin is a key iron-regulatory hormone, the production of which is controlled by iron stores, inflammation, hypoxia and erythropoiesis. The regulation of iron by hepcidin is of clinical importance in thalassemia patients in which anemia occurs along with iron overload. The present study aimed to evaluate the correlation between serum hepcidin and ferritin levels in thalassemia patients. This cross-sectional study investigated 64 patients with thalassemia; 16 β-thalassemia major (BTM), 31 β-thalassemia/hemoglobin (Hb) E (BE), and 17 Hb H + AE Bart’s disease (Hb H + AE Bart’s). The levels of serum hepcidin and ferritin, and Hb of the three groups were measured. The median values of serum ferritin and Hb were significantly different among the three groups, whereas serum hepcidin values were not observed to be significantly different. The correlation of the serum hepcidin and ferritin levels was not statistically significant in any of the three groups of thalassemia patients with BTM, BE, or Hb H + AE Bart’s (r = −0.141, 0.065 and −0.016, respectively). In conclusion, no statistically significant correlations were observed between serum hepcidin with any variables including serum ferritin, Hb, age, labile plasma iron (LPI), and number of blood transfusion units among the three groups of thalassemia patients. Likely, the regulation of hepcidin in thalassemia patients is affected more by erythropoietic activity than iron storage. 相似文献
44.
45.
Erin S. Luetkemeier Ripan S. Malhi Jonathan E. Beever Lawrence B. Schook 《Immunogenetics》2009,61(2):119-129
The major histocompatibility complex (MHC) is an immunological gene-dense region of high diversity in mammalian species. Sus scrofa was domesticated by at least six independent events over Eurasia during the Holocene period. It has been hypothesized that
the level and distribution of MHC variation in pig populations reflect genetic selection and environmental influences. In
an effort to define the complexity of MHC polymorphisms and the role of selection in the generation of class II gene diversity
(DQB, DRB1, and pseudogene ΨDRB3), DNA from globally distributed unrelated domestic pigs of European and Asian origins and
a Suidae out-group was analyzed. The number of pseudogene alleles identified (ΨDRB3 33) was greater than those found in the
expressed genes (DQB 20 and DRB1 23) but the level of observed heterozygosity (ΨDRB3 0.452, DQB 0.732, and DRB1 0.767) and
sequence diversity (ΨDRB3 0.029, DQB 0.062, and DRB1 0.074) were significantly lower in the pseudogene, respectively. The
substitution ratios reflected an excess of d
N (DQB 1.476, DRB1 1.724, and ΨDRB3 0.508) and the persistence of expressed gene alleles suggesting the influence of balancing
selection, while the pseudogene was undergoing purifying selection. The lack of a clear MHC phylogeographic tree, coupled
with close genetic distances observed between the European and Asian populations (DQB 0.047 and DRB1 0.063) suggested that
unlike observations using mtDNA, the MHC diversity lacks phylogeographic structure and appears to be globally uniform. Taken
together, these results suggest that, despite regional differences in selective breeding and environments, no skewing of MHC
diversity has occurred.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
46.
Major histocompatibility complex variation at class II DQA locus in the brown hare (Lepus europaeus)
E. A. KOUTSOGIANNOULI K. A. MOUTOU T. SARAFIDOU C. STAMATIS V. SPYROU† Z. MAMURIS 《Molecular ecology》2009,18(22):4631-4649
The major histocompatability complex (MHC) is a multigene family of receptors that bind and present antigenic peptides to T-cells. Genes of the MHC are characterized by an outstanding genetic polymorphism, which is considered to be maintained by positive selection. Sites involved in peptide binding form binding pockets (P) that are collectively termed the peptide-binding region (PBR). In this study, we examined the level of MHC genetic diversity within and among natural populations of brown hare ( Lepus europaeus ) from Europe and Anatolia choosing for analysis of the second exon of the DQA locus, one of the most polymorphic class II loci. We aimed at an integrated population genetic analysis of L. europeaus by (i) correlating MHC polymorphism to genetic variability and phylogenetic status estimated previously from maternally (mtDNA) and biparentally (allozymes, microsatellites) inherited loci; and (ii) comparing full-length exon amino acid polymorphism with functional polymorphism in the PBR and the binding pockets P1, P6 and P9. A substantial level of DQA exon 2 polymorphism was detected with two completely different set of alleles between the Anatolian and European populations. However, the phylogeny of full-length exon 2 Leeu-DQA alleles did not show a strong phylogeographic signal. The presence of balancing selection was supported by a statistically significant excess of nonsynonymous substitutions over synonymous in the PBR and a trans-species pattern of evolution detected after phylogenetic reconstruction. The differentiating patterns detected between genetic and functional polymorphism, i.e. the number and the distribution of pocket variants within and among populations, indicated a hierarchical action of selection pressures. 相似文献
47.
48.
苹果酸脱氢酶(Malate Dehydrogenase,MD)是一种氧化还原性酶,参与体内多种能量代谢反应.它可以催化苹果酸氧化脱羧生成丙酮酸和CO2,并使NADP+还原成NADPH,NADPH是脂肪酸合成所必需的载体,棕榈酸可以利用生成的NADPH来合成长链脂肪酸,MD的活性与脂肪酸合成效率之间存在密切的相关,MD也参与体内骨骼肌、心肌的能量代谢,并对肌纤维的生长有一定的调节作用.根据鸡MD基因的5侧翼区序列设计一对引物,用直接测序的方法在侧翼区检测多态性位点,在235bp(GenBank登录号U49693)处发现一个SNP位点,此位点是一个限制性内切酶(SphⅠ酶)发生变化的位点.以东北农业大学高低脂双向选择系的第8世代肉鸡和东农F2资源群体为实验材料,用PCR-RFLP的方法进行基因型分析,建立适合的统计模型,进行基因型与生长和体组成性状的相关分析.结果表明在高低脂系第8世代肉鸡中AA基因型个体的腹脂重和腹脂率显著高于BB基因型个体(P<0.05);BB基因型个体的大胸肌重和大胸肌率显著高于AA基因型个体(P<0.05).在东农F2资源家系中BB基因型个体的大胸肌重和大胸肌率显著高于AA和AB基因型个体(P<0.05);AA基因型个体的肝脏重和肝脏率显著高于BB基因型个体(P<0.05).综上所述,MD基因可能是影响鸡生长和体组成性状的主效基因或与控制生长和体组成性状的主效基因相连锁. 相似文献
49.
Based on the traditional polygene inheritance model of quantitative traits,the author suggests the major gene and polygene mixed inheritance model.The model was considered as a general one,while the pure major gene and pure polygene inheritance model was a specific case of the general model.Based on the proposed theory,the author established the segregation analysis procedure to study the genetic system of quantitative traits of plants.At present,this procedure can be used to evaluate the genetic effect of individual major genes (up to two to three major genes),the collective genetic effect of polygene,and their heritability value.This paper introduces how to establish the procedure,its main achievements,and its applications.An example is given to illustrate the steps,methods,and effectiveness of the procedure. 相似文献
50.
辣椒株高遗传分析 总被引:7,自引:3,他引:4
以辣椒矮秆自交系B9431(P1)和高秆自交系‘吉林长椒’(P2)为双亲,构建P1、F1、P1、B1、B2和F2 6个家系世代群体,应用植物数量性状主基因+多基因混合遗传模型对该6个世代群体株高进行多世代联合分析,结果显示:株高遗传符合1对主基因+多基因遗传模型,高秆对矮秆表现为不完全显性,F1代株高的势能比值为0.39,显性程度为0.91。B1、B2和F2群体主基因遗传率分别为20.35%、17.20%和35.29%,多基因遗传率分别为5.08%、19.75%和0;主基因效应表现为负向加性效应,其值为-6.43,显性效应为0;多基因加性效应值和显性效应值分别为-8.89和9.77。研究还表明,主基因与多基因间的基因效应存在一定差异,主基因加性效应值相当于多基因加性效应值的72.33%,主基因无显性效应,显性效应是由多基因控制遗传。 相似文献