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1.
Nine pairs of polymerase chain reaction (PCR) primers that amplify polymorphic microsatellite loci in the desert locust, Schistocerca gregaria (Forskal), were developed using a magnetic bead‐based enrichment protocol. A sample of 48 locusts collected during the 1993 and 1995 upsurge periods in Eritrea, East Africa, were genotyped. The number of alleles per locus ranged from six to 20; the average was 12.67. Allelic distributions were significantly different between samples from different localities. 相似文献
2.
In searching for differentially expressed genes in human uterine leiomyomas (ULs), suppression sub-tractive hybridization was used to construct an UL up-regulated library, which turned out to represent 88genes. After two rounds of screening by reverse Northern analysis, twenty genes were proved to be up-regulated, including seventeen known genes and three genes with unknown function. All these genes werefirstly associated with UL. Three genes with notable difference were selected for Northern confirmationOur results proved the authenticity of the twenty genes. One gene named Phospholipase A2 (PLA2) showedup-regulation in 4/6 of the patients and investigation of tissue distribution indicated that it had obviousexpression in prostate, testis, liver, heart and skeletal muscle. 相似文献
3.
J. M. SORIANO S. PECCHIOLI C. ROMERO S. VILANOVA G. LLCER E. GIORDANI M. L. BADENES 《Molecular ecology resources》2006,6(2):368-370
The oriental persimmon (Diospyros kaki Lf) is believed to have originated in China with subsequent introduction into Japan and Korea in ancient times. The species was then brought to Europe, Brazil and the USA from Japan in the 19th century. Recent studies highlighted the poor state of identification of cultivars in these countries due to incorrect labelling and presence of synonyms among local varieties. Thus, molecular marker characterization of germplasm resources is of great value for genetic resource preservation and plant breeding of persimmon. Therefore, to identify accessions for further plant breeding and germplasm management, 37 microsatellite loci were developed from a CT/AG‐enriched persimmon genomic library. 相似文献
4.
Six polymorphic dinucleotide microsatellite loci were isolated and characterized from the White‐chinned Petrel Procellaria aequinoctialis, using a degenerate primer and PCR‐based technique to construct and screen an enriched genomic library. Preliminary data on three populations show heterozygosity levels ranging from 0.22 to 0.67 and allele numbers from three to nine. Preliminary data also suggest genetic distance between these three populations (FST 0.088). Cross‐species amplification of these six microsatellite loci and one further locus were tested in six other procellariiform species of the genus Procellaria, Macronectes, Thalassarche and Diomedea. 相似文献
5.
Molecular cloning of cDNA for human prostatic acid phosphatase 总被引:1,自引:0,他引:1
A human liver cDNA library in λgt11 was screened with polyclonal antiserum to human acid phosphatase isoenzyme 2a/4. About eleven positive clones have been obtained. Two clones, λ Hap21 and λ Hap22 were further characterized: clone λHap21 contained a 0.8-kb cDNA insert and clone λHap22 a 1.8–2.0-kb insert. XbaI digestion of λHap22 generated two fragments of 1.0 and 0.9 kb. BglII digestion resulted in a 1.2-kb fragment and several smaller fragments of undetermined size. Clone 1 Hap22 contained all the genes carried by λ gt11(lac 5cI857nin 5Sam 100) and the 2-kb insert. An Escherichia coli(λHap22) lysogen was generated, and its acid phosphatase activity was approximately ten-fold higher than that in the control nonlysogenic lysate. Western-blot analysis of total proteins present in this E. coli(λHap22) lysate revealed that the non-induced λHap22 prophage directed the synthesis of an approx. 175-kDa protein. This protein was recognized by antibody to the human acid phosphatase isoenzyme 2a/4 and anti-β-galactosidase and was produced only upon induction with IPTG. These results indicated that AHap22 carried a major portion of the gene coding for the human acid phosphatase isoenzyme 2a and/or 4 and this protein fragment of acid phosphatase was sufficient to manifest enzymatic activity. 相似文献
6.
7.
Radiolabelled calmodulin has previously been used to screen cDNA expression libraries to isolate calmodulin-binding proteins.
We have modified this technique for the isolation of plant calmodulin-binding proteins. [35S]-methionine was used instead of the inorganic [35S]-sulfate, or125I used in previous methods. In addition, theE. coli pET expression system was chosen to obtain high levels of recombinant calmodulin at the time of labelling. The procedure
thus takes into account both the specific activity of the probe and the amount of protein necessary for screening a large
number of filters. Here we describe in detail a procedure for the production and purification of [35S]-recombinant calmodulin and the use of the radiolabelled protein as a probe to screen plant cDNA expression libraries. The
[35S]-labeled calmodulin probe easily detects the λICM-1 phage encoding a partial mouse calmodulin-dependent protein kinase II
that was previously isolated using a [125I]-calmodulin probe (Sikela and Hahn, 1987). Subsequently, a tobacco root cDNA expression library was screened and a positive
clone encoding a calcium-dependent calmodulin-binding protein was isolated. 相似文献
8.
Sarah Jane Gurr Michael J. McPherson Claire Scollan Howard J. Atkinson Dianna J. Bowles 《Molecular & general genetics : MGG》1991,226(3):361-366
Summary A major pathogen of potato plants (Solanum tuberosum) is the potato cyst nematode (Globodera spp.), which induces localized redifferentiation of a limited number of host cells to form a specialized feeding-site termed the syncytium. A novel strategy utilizing the polymerase chain reaction (PCR) was employed to construct a cDNA library from dissected potato roots highly enriched in syncytial material. The library was differentially screened with cDNA probes derived from the infected root tissue from a compatible interaction and from healthy root tissue. Characterization of one gene identified by the library screen indicated an expression pattern that correlated with events in the immediate vicinity of the pathogen after syncytial establishment. The strategy for library construction and screening could be applicable to the study of gene expression in any plant-pathogen interaction in which the limited supply of cells at the interface of the two organisms precludes a more traditional approach. 相似文献
9.
Christian Boucher Anne Martinel Patrick Barberis Genevieve Alloing Claudine Zischek 《Molecular & general genetics : MGG》1986,205(2):270-275
Summary A class of avirulent mutants of the plant pathogenic bacterium Pseudomonas solanacearum, strain GMI1000, resistant to acridine orange (Acrr), harbour a deletion of over 85 kb in their genome. This deletion affects, a1,000 kb megaplasmid which has previously been shown to be present in most of the strains of this species. In addition at least 11 out of 13 independent Tn5 insertions, leading to loss of virulence, are located on the megaplasmid. Nine of them are present in the region which is deleted from the Acrr mutants. These results suggest that the majority of virulence genes identified so far are plasmid borne. 相似文献
10.
Flora Sánchez Angeles Touriño Susana Traseira Agustín Pérez-Aranda Víctor Rubio Miguel A. Peñalva 《Molecular & general genetics : MGG》1986,205(2):248-252
Summary We cloned the Penicillium chrysogenum trpC gene from a genomic library by complementation of an Escherichia coli trpC mutant lacking phosphoribosylanthranilate isomerase activity. The gene ecodes a 2.7 kb poly(A)+ RNA. We localized the gene by sequence analysis in a 2.9 kb DNA insert found in the smallest plasmid selected from the library. Sequence data strongly suggest that the organization of the gene is similar to that described in other Ascomycetes. We found that a DNA fragment which codes only for the carboxy-terminal protion of the polypeptide is sufficient for complementation of the E. coli trpC9830 mutation. 相似文献