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991.
992.
Han R Wei Y Kang X Chen H Sun G Li G Bai Y Tian Y Huang Y 《Molecular biology reports》2012,39(3):3153-3160
The PR domain containing 16 (PRDM16) is a member of the Prdm family, and is known to regulate cell differentiation. In the
present study, DNA pool sequencing methods were employed to screen genetic variations in the chicken PRDM16 gene. The results revealed four novel single nucleotide polymorphisms (SNPs): NC_006108.2: g.92188G>A, XM_417551: c.1161C>T
(Ala/Ala, 387aa), c.1233C>T (Ser/Ser, 411aa) and c.1433G>A (Ser/Asn, 478aa). The BglI polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) was used to detect c.1161C>T, while HhaI Forced PCR-RFLP methods were used to detect 1233C>T and c.1433G>A in 964 chickens. The chickens comprised 38 grandparents,
66 F1 parents and 860 F2 birds derived from an F2 resource population of Gushi chickens crossed with Anka broilers. The associations of the polymorphisms in the chicken PRDM16 gene with performance traits were analyzed in the 860 F2 chickens. The results indicated that the three SNPs were significantly associated with growth, fatness and meat quality traits
in the chickens. In particular, the polymorphisms of the missense SNP (c.1433G>A) had positive effects on chicken body weight
and body size at different stages. It affected also fatness traits significantly. Comparison of the different genotypes of
c.1433G>A showed that the GG genotype favored chicken growth and fatness traits. 相似文献
993.
Application of pyrosequencing of six Salmonella-specific genes as a rapid Salmonella identification method was tested. Primers for hns, hisJ and hilA had non-specific reactions with non-Salmonella strains. Primers for invA, iroB and fimY had specific PCR products and pyrosequences of Salmonella, suggesting that they were suitable for Salmonella rapid identification. 相似文献
994.
Hou X Tian H Wu J Tao J Chen Y Yin S Zhang K Shang Y Liu X 《Journal of biotechnology》2012,161(3):221-227
The E2 envelope glycoprotein is the major immunodominant protein of classical swine fever virus (CSFV), and can induce neutralizing antibodies and protective immune responses in infected swine. We developed a tandem-repeat multiple-epitope recombinant protein that contains two copies of each of the regions of E2 spanned by residues 693-704, 770-780, and 826-843, coupled by two copies of the region spanned by residues 1446-1460 of the CSFV nonstructural protein NS2-3. The chemically synthesized gene was expressed in Escherichia coli as a fusion with glutathione S-8 (GST), named GST-BT21. After it was purified with Glutathione Sepharose 4B, we used Western blotting to characterize the construct and surface plasmon resonance to analyze its affinity and specific interaction with CSFV-positive serum. Purified GST-BT21 protein displayed excellent immunoreactivity with antiserum against CSFV (Tian et al., 2012), and surface plasmon resonance confirmed the specific affinity between BT21, but not GST, and antibodies in serum from animals infected with CSFV. Surface plasmon resonance is a sensitive and precise method for epitope evaluation, and it can be used to characterize the immunogenicity and functions of recombinant proteins. 相似文献
995.
Yuanjing Li Chunjie Tian Hua Tian Jiliang Zhang Xin He Wenxiang Ping Hong Lei 《Applied microbiology and biotechnology》2012,96(6):1479-1487
Nowadays, bacterial cellulose has played more and more important role as new biological material for food industry and medical and industrial products based on its unique properties. However, it is still a difficult task to improve the production of bacterial cellulose, especially a large number of byproducts are produced in the metabolic biosynthesis processes. To improve bacterial cellulose production, ethanol and sodium citrate are added into the medium during the fermentation, and the activities of key enzymes and concentration of extracellular metabolites are measured to assess the changes of the metabolic flux of the hexose monophosphate pathway (HMP), the Embden–Meyerhof–Parnas pathway (EMP), and the tricarboxylic acid cycle (TCA). Our results indicate that ethanol functions as energy source for ATP generation at the early stage of the fermentation in the HMP pathway and the supplementation of ethanol significantly reduces glycerol generation (a major byproduct). While in the EMP pathway, sodium citrate plays a key role, and its supplementation results in the byproducts (mainly acetic acid and pyruvic acid) entering the gluconeogenesis pathway for cellulose synthesis. Furthermore, by adding ethanol and sodium citrate, the main byproduct citric acid in the TCA cycle is also reduced significantly. It is concluded that bacterial cellulose production can be improved by increasing energy metabolism and reducing the formation of metabolic byproducts through the metabolic regulations of the bypasses. 相似文献
996.
Hongyu Tian Karthikeyan Mythreye Christelle Golzio Nicholas Katsanis Gerard C Blobe 《The EMBO journal》2012,31(19):3885-3900
Both the transforming growth factor β (TGF-β) and integrin signalling pathways have well-established roles in angiogenesis. However, how these pathways integrate to regulate angiogenesis is unknown. Here, we show that the extracellular matrix component, fibronectin, and its cellular receptor, α5β1 integrin, specifically increase TGF-β1- and BMP-9-induced Smad1/5/8 phosphorylation via the TGF-β superfamily receptors endoglin and activin-like kinase-1 (ALK1). Fibronectin and α5β1 integrin increase Smad1/5/8 signalling by promoting endoglin/ALK1 cell surface complex formation. In a reciprocal manner, TGF-β1 activates α5β1 integrin and downstream signalling to focal adhesion kinase (FAK) in an endoglin-dependent manner. α5β1 integrin and endoglin form a complex on the cell surface and co-internalize, with their internalization regulating α5β1 integrin activation and signalling. Functionally, endoglin-mediated fibronectin/α5β1 integrin and TGF-β pathway crosstalk alter the responses of endothelial cells to TGF-β1, switching TGF-β1 from a promoter to a suppressor of migration, inhibiting TGF-β1-mediated apoptosis to promote capillary stability, and partially mediating developmental angiogenesis in vivo. These studies provide a novel mechanism for the regulation of TGF-β superfamily signalling and endothelial function through crosstalk with integrin signalling pathways. 相似文献
997.
Aims: The present study was conducted to evaluate the possibility of using cyanobacterial bloom materials as a medium for white rot fungi and the capability of white rot fungi, Trichaptum abietinum 1302BG and Lopharia spadicea to biodegrade dried cyanobacterial bloom material taken from Taihu Lake. Methods and Results: The results showed T. abietinum 1302BG and L. spadicea could use the cyanobacterial bloom materials taken from Taihu Lake for growth to measure the mycelial plaque and dry‐weight mycelial pellicles of fungi. The removal rate of dried cyanobacterial bloom materials incubated with white rot fungi is approximately 100%. Conclusions: The cyanobacterial bloom material can be used as a glucose substitute in white rot fungi medium. The white rot fungi, T. abietinum 1302BG and L. spadicea, can also directly decrease the biomass of cyanobacterial bloom material taken from Taihu Lake. Significance and Impact of the Study: Cyanobacterial bloom thrives in eutrophic fresh waters all over the world. Micro‐organisms, particularly fungi, have attracted attention as possible agents for the degradation of phytoplankton species. Dealing with cyanobacterial bloom material as a medium for fungi instead of directly discharging them as organic fertilizers is a new, safe and environmentally friendly approach. 相似文献
998.
NJ Krautler V Kana J Kranich Y Tian D Perera D Lemm P Schwarz A Armulik JL Browning M Tallquist T Buch JB Oliveira-Martins C Zhu M Hermann U Wagner R Brink M Heikenwalder A Aguzzi 《Cell》2012,150(1):194-206
The differentiation of follicular dendritic cells (FDC) is essential to the remarkable microanatomic plasticity of lymphoid follicles. Here we show that FDC arise from ubiquitous perivascular precursors (preFDC) expressing platelet-derived growth factor receptor β (PDGFRβ). PDGFRβ-Cre-driven reporter gene recombination resulted in FDC labeling, whereas conditional ablation of PDGFRβ(+)-derived cells abolished FDC, indicating that FDC originate from PDGFRβ(+) cells. Lymphotoxin-α-overexpressing prion protein (PrP)(+) kidneys developed PrP(+) FDC after transplantation into PrP(-) mice, confirming that preFDC exist outside lymphoid organs. Adipose tissue-derived PDGFRβ(+) stromal-vascular cells responded to FDC maturation factors and, when transplanted into lymphotoxin β receptor (LTβR)(-) kidney capsules, differentiated into Mfge8(+)CD21/35(+)FcγRIIβ(+)PrP(+) FDC capable of trapping immune complexes and recruiting B cells. Spleens of lymphocyte-deficient mice contained perivascular PDGFRβ(+) FDC precursors whose expansion required both lymphoid tissue inducer (LTi) cells and lymphotoxin. The ubiquity of preFDC and their strategic location at blood vessels may explain the de novo generation of organized lymphoid tissue at sites of lymphocytic inflammation. 相似文献
999.
A new guar gum derivative containing amino group was synthesized through nucleophilic substitution of p-toluenesulfonate activated hydroxypropyl guar gum with ethanolamine. For the preparation of p-toluenesulfonate esters hydroxypropyl guar gum, the results showed that the reaction rate was optimal at 25°C and the reaction could reach equilibrium state when it was carried out for 10h at 25°C. For the nucleophilic substitution of tosyl group with ethanolamine, the reaction was completed after 10h reaction at 50°C. The structures of products were characterized by NMR and FT-IR spectroscopy. The results showed that the p-toluenesulfonate esters can be effectively substituted by ethanolamine to form the hydroxyethyl amino hydroxypropyl guar gum (EAHPG). The content of nitrogen of EAHPG was determined by acid-base titration and element analysis. 相似文献
1000.
Zhu B Liu H Tian WX Fan XY Li B Zhou XP Jin GL Xie GL 《Journal of bacteriology》2012,194(5):1280-1281
Stenotrophomonas maltophilia is an endophyte which plays important roles in agricultural production as a plant growth-promoting bacterium. Here, we present the draft genome sequence of strain RR-10, which was isolated from a rice root in a rice field of China. 相似文献