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91.
小麦Kr基因在小麦与玉米或鸭茅状摩擦禾杂交中的失活 总被引:2,自引:0,他引:2
用37个小麦(Triticumaestivum)品种(系)为母本,分别与黑麦(Secalecereale)、球茎大麦(Hordeumbulbosum)、玉米(Zeamays)和鸭茅状摩擦禾(Tripsacumdactyloides)杂交,比较其亲和性,小麦和玉米或鸭茅状摩擦禾杂交比小麦与黑麦或球茎大麦杂交的亲和性显著提高。携带着显性Kr1和Kr2基因的小麦品种Hope与黑麦杂交,不能形成胚,而与玉米及鸭茅状摩擦禾杂交时,成胚率分别达16.00%和32.50%。表明控制小麦与黑麦及球茎大麦杂交亲和性的Kr基因系统在小麦与玉米及小麦与鸭茅状摩擦禾属间杂交中失活。讨论了还存在有其它控制小麦属间杂交亲和性的遗传调控系统的可能性。 相似文献
92.
Sequence-tagged-site (STS) markers of arbitrary genes: the utility of black spruce-derived STS primers in other conifers 总被引:4,自引:0,他引:4
D. J. Perry J. Bousquet 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(5-6):735-743
Sequence-tagged-site primers, previously developed based upon black spruce (Picea mariana) cDNA sequences, were tested for their ability to direct specific amplification in two individuals of each of 12 additional
conifer species. Nearly all (95–97%) of the primers functioned well in congeneric trials, while a lower proportion (21–33%)
scored positively in other Pinaceae genera. Outside of the Pinaceae, amplification of homologous products was not achieved.
Products from the various species often differed in size from their homologs in black spruce. In one case a large difference
in size was due to the lack of an intron in a jack pine product while in several other cases the differences were due to the
presence or absence of large direct repeats in the DNA sequences. Length polymorphism was occasionally evident between the
two individuals examined of a given species. We investigated marker polymorphism in detail in a panel of 15 white spruce (Picea glauca) trees. Allelic segregation among haploid megagametophytes was revealed directly at 16 loci by standard agarose-gel electrophoresis
without any additional manipulation of amplification products. Polymorphisms observed at 12 of these loci were exclusively
co-dominant. For this subset of 12 loci, the average number of alleles was 3.2 and the average observed heterozygosity was
0.37.
Received: 10 April 1998 / Accepted: 22 April 1998 相似文献
93.
B. M. Baltazar A. L. Scharen W. E. Kronstad 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1990,79(3):422-426
Summary Differences in levels of resistance toSeptoria tritici blotch were observed in plants with a specific height-reducing gene. When the gene Rht
2 was present either as an isoline or in the progeny, a higher degree of resistance was found. The most susceptible plants were observed in populations carrying the Rht
1 gene. Associations, as determined by phenotypic correlations, were detected betweenSeptoria tritici blotch and tall stature, late heading, and maturity. Plants having short stature, early heading, early maturity, and acceptable levels of resistance were identified in the F2 population whenRht
2 was present. Results of this study indicated that wheat breeders must select the appropriate dwarfing source that may confer resistance and grow large F2 populations, in order to increase the probability of obtaining desired genotypes. 相似文献
94.
玉米是杂种优势利用最成功的作物之一,采用细胞质雄性不育(CMS)进行玉米杂交种生产已成为杂种优势利用的有力工具。CMS是由于细胞质和细胞核的基因表达产物的不协调而产生的不育性,可被核基因组中的恢复基因恢复。根据育性恢复专效性,玉米CMS材料主要分为T、C和S三种类型。综述了这三种类型不育及其恢复基因的研究进展,分析了在不育化制种中的应用情况。 相似文献
95.
96.
Lee H. Pratt Marie-Michèle Cordonnier-Pratt Bernard Hauser Michel Caboche 《Planta》1995,197(1):203-206
Tomato (Solanum lycopersicon L.) contains two B-type phytochrome genes (PHYB1 and PHYB2). Fragments of these two PHYB were cloned following amplification by the polymerase chain reaction of a portion of their relatively well conserved 5 coding regions. Polypeptides encoded by these gene fragments exhibit 90% sequence identity. These two PHYB are independently expressed in organ-specific fashion. In mature plants, PHYB2 mRNA is most abundant in fruit and PHYB1 mRNA in expanded leaves. A phylogenetic analysis fails to establish which tomato PHYB is orthologous to either Arabidopsis PHYB or PHYD, the latter being a second B-type phytochrome. Instead, this analysis indicates that following the divergence of the Solanaceae and Brassicaceae from one another, a PHYB gene duplicated independently in each lineage. Consequently, Arabidopsis PHYB mutants cannot be considered strictly equivalent to the tomato tri mutants, which appear to be mutated at the PHYB1 locus. Similarly, other putative PHYB mutants might not be equivalent to those described for Arabidopsis and tomato. This situation complicates efforts to determine PHYB function because there might be no one answer to this question.Abbreviations PCR
polymerase chain reaction
-
PHY
undesignated phytochrome gene
-
PHYA, PHYB, etc
phytochrome gene(s) of the A, B, etc. type
This research was supported by USDA NRICGP grant 93-00939 and by NATO travel grant CRG 931183. It was initiated when two of us (L.H.P., M.-M.C.-P.) spent a sabbatical year at the Institut National de la Recherche Agronomique in Versailles, France. L.H.P. gratefully acknowledges support provided by a senior guest fellowship from the Ministère de l'enseignement superieur et de la recherche during his stay in Versailles. L.H.P. and M.-M.C.-P thank all of their colleagues in Versailles for their warm hospitality and their willingness to share their expertise with us. We also thank Russell Malmberg, Richard Meagher and Robert Price for helpful discussions concerning the interpretation of molecular phylogenies. 相似文献
97.
V. S. Baranov 《Molecular Biology》2000,34(4):590-600
New trends in molecular medicine that have emerged owing to the success of the national Human Genome program are characterized.
The major attention is paid to molecular diagnostics, preventive medicine, and gene therapy. Preventive medicine is a product
of synthesis of the current notions on genetics and biochemistry of human diseases; it comprises pharmacogenetics, presymptomatic
diagnosis, and testing of genes of predisposition to the most frequent multifactor diseases. In the Gene Therapy section,
advantages and drawbacks of the main methods of delivery of nucleic acids into the cells are considered; diseases that are
attempted to be rectified using gene therapy are listed. Exemplified with Duchenne myodystrophy, the problems encountered
in correction of a genetic defect with the aid of foreign genes are considered. Results are summarized for assessing the efficiency
of various methods of introduction of dystrophin cDNA (gene gun, liposomes, microspheres, viral oligopeptides, and lactoferrin)
conducted on the Duchenne myodystrophy model, mdx mice. 相似文献
98.
Mishra RK Yamagishi T Vasanthi D Ohtsuka C Kondo T 《Genesis (New York, N.Y. : 2000)》2007,45(9):570-576
Temporal colinearity in mouse HoxD is dependent on repressive activity of sequences within the 5' end of the complex. We show that a 5-kb DNA fragment from this region represses transgenes when combined in mouse as well as in Drosophila melanogaster. Moreover, repressive activity in Drosophila depends on some members of the Polycomb-group (PcG) genes, for example, extra sex combs. We also showed direct association of these factors with the repressive fragment, both in transgenic flies and in the context of the native mouse HoxD complex. These results suggest that the global repressive region of the HoxD complex functions in two very different species and that some PcG genes are involved in establishing the early repressive state of the HoxD complex, thus contributing to temporal colinearity. 相似文献
99.
Roberts MC 《Molecular biotechnology》2002,20(3):261-283
The discovery and use of antimicrobial agents in the last 50 yr has been one of medicine’s greatest achievements. These agents
have reduced morbidity and mortality of humans and animals and have directly contributed to human’s increased life span. However,
bacteria are becoming increasingly resistant to these agents by mutations, which alter existing bacterial proteins, and/or
acquisition of new genes, which provide new proteins. The latter are often associated with mobile elements that can be exchanged
quickly across bacterial populations and may carry multiple antibiotic genes fo resistance. In some case, virulence factors
are also found on these same mobile elements. There is mounting evidence that antimicrobial use in agriculture, both plant
and animal, and for environmental purposes does influence the antimicrobial resistant development in bacteria important in
humans and in reverse. In this article, we will examine the genes which confer resistance to tetracycline, macrolide-lincosamide-streptogramin
(MLS), trimethoprim, and sulfonamide. 相似文献
100.
Cancer-related genes harbored in the loss regions containing a high frequency of hepatocellular carcinoma (HCC) were selected.Related information was gathered and the coding single nucleotide polymorphism (cSNP) sequences were obtained from the single nucleotide polymorphism (SNP) database.The appropriate primers and oligonucleotide probes were then designed in accordance with the SNP sites,and subsequently,the gene chips for detecting SNPs were constructed.Genomic DNA was extracted from blood samples of healthy controls and from patients with HBV infection.The sequences,including the SNPs,were amplified via polymerase chain reaction (PCR) and labeled using digoxigenin deoxyuridine tri-phosphate (Dig-dUTP).The labeled products were then hybridized with the SNP chips.Results confirmed that the differences in allele frequencies of three SNPs EGFL3 (rs947345),Caspase9 (rs2308950),and E2F2 (rs3218171) were distinct between HBV-infected patients and controls,suggesting that these SNPs ocuring in high frequency in HBV-infected individuals may be associated with susceptibility to HCC. 相似文献