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991.
Hye Jin Choi Thummala Chandrasekhar Hyo-Yeon Lee Kyung-Moon Kim 《Plant Cell, Tissue and Organ Culture》2007,91(3):235-242
Transgenic herbicide-resistant sweet potato plants [Ipomoea batatas (L.) Lam.] were produced through Agrobacterium-mediated transformation system. Embryogenic calli derived from shoot apical meristems were infected with Agrobacterium tumefaciens strain EHA105 harboring the pCAMBIA3301 vector containing the bar gene encoding phosphinothricin N-acetyltransferase (PAT) and the gusA gene encoding β-glucuronidase (GUS). The PPT-resistant calli and plants were selected with 5 and 2.5 mg l−1 PPT, respectively. Soil-grown plants were obtained 28–36 weeks after Agrobacterium-mediated transformation. Genetic transformation of the regenerated plants growing under selection was demonstrated by PCR,
and Southern blot analysis revealed that one to three copies of the transgene were integrated into the plant genome of each
transgenic plant. Expression of the bar gene in transgenic plants was confirmed by RT-PCR and application of herbicide. Transgenic plants sprayed with Basta containing
900 mg l−1 of glufosinate ammonium remained green and healthy. The transformation frequency was 2.8% determined by herbicide application
which was high when compared to our previous biolistic method. In addition, possible problems with multiple copies of transgene
were also discussed. We therefore report here a successful and reliable Agrobacterium-mediated transformation of the bar gene conferring herbicide-resistance and this method may be useful for routine transformation and has the potential to develop
new varieties of sweet potato with several important genes for value-added traits such as enhanced tolerance to the herbicide
Basta. 相似文献
992.
Savithiry S. Natarajan Chenping Xu Hanhong Bae Thomas J. Caperna Wesley Garrett 《Plant Molecular Biology Reporter》2007,25(1-2):55-62
Optimizing the amounts of proteins required to separate and characterize both abundant and less abundant proteins by two-dimensional
polyacrylamide gel electrophoresis (2D-PAGE) is critical for conducting proteomic research. In this study, we tested five
different levels of soybean seed proteins (75, 100, 125, 150, and 200 μg) by 2D-PAGE. Following 2D-PAGE and spot excision,
proteins were identified by mass spectrometry analysis. The number of visible protein spots was increased with an increase
in the amount of protein loaded. The intensity of highly abundant proteins [β-conglycinin β-homotrimer and glycinin G4 (A5A4B3)
precursors] increased linearly between 75 and 125 μg, whereas the proglycinin G3 (A1ab1b) homotrimer showed linearity between
75 and 150 μg. The spot intensity of less abundant proteins, glycinin G2 (A2b1a) precursor and proglycinin G3 (A1ab1b) homotrimer,
increased linearly with an increase in the amount of protein through 200 μg, whereas spot intensity of β-conglycinin β-homotrimer
and the allergen Gly m bd 28K increased linearly until 150 μg and did not increase further at 200 μg. These results suggest
that 150 μg protein was a suitable amount for the separation of abundant proteins, and 200 μg protein was suitable for the
separation of less abundant proteins prepared from soybean seeds.
Mention of trade name, proprietary product or vendor does not constitute a guarantee or warranty of the product by the U.S.
Department of Agriculture or imply its approval to the exclusion of other products or vendors that also may be suitable. 相似文献
993.
Zhao Y He D Stern R Usatyuk PV Spannhake EW Salgia R Natarajan V 《Cellular signalling》2007,19(11):2329-2338
Previously we demonstrated that ligation of lysophosphatidic acid (LPA) to G protein-coupled LPA receptors induces transactivation of receptor tyrosine kinases (RTKs), such as platelet-derived growth factor receptor beta (PDGF-Rbeta) and epidermal growth factor receptor (EGF-R), in primary cultures of human bronchial epithelial cells (HBEpCs). Here we examined the role of LPA on c-Met redistribution and modulation of hepatocyte growth factor (HGF)/c-Met pathways in HBEpCs. Treatment of HBEpCs with LPA-induced c-Met serine phosphorylation and redistribution to plasma membrane, while treatment with HGF-induced c-Met internalization. Pretreatment with LPA reversed HGF-induced c-Met internalization. Overexpression of dominant negative (Dn)-PKC delta or pretreatment with Rottlerin or Pertussis toxin (PTx) attenuated LPA-induced c-Met serine phosphorylation and redistribution. Co-immnuoprecipitation and immunocytochemistry showed that E-cadherin interacted with c-Met in HBEpCs. LPA treatment induced E-cadherin and c-Met complex redistribution to plasma membranes. Overexpression of Dn-PKC delta attenuated LPA-induced E-cadherin redistribution and E-cadherin siRNA attenuated LPA-induced c-Met redistribution to plasma membrane. Furthermore, pretreatment of LPA attenuated HGF-induced c-Met tyrosine phosphorylation and downstream signaling, such as Akt kinase phosphorylation and cell motility. These results demonstrate that LPA regulates c-Met function through PKC delta and E-cadherin in HBEpCs, suggesting an alternate function of the cross-talk between G-protein-coupled receptors (GPCRs) and RTKs in HBEpCs. 相似文献
994.
Savithiry Natarajan Chenping Xu Hanhong Bae Bryan A Bailey Perry Cregan Thomas J Caperna Wesley M Garrett Devanand Luthria 《Plant Physiology and Biochemistry》2007,45(6-7):436-444
We investigated proteomic and genomic profiles of glycinin, a family of major storage proteins in 16 different soybean genotypes consisting of four groups including wild soybean (Glycine soja), unimproved cultivated soybean landraces from Asia (G. max), ancestors of N. American soybean (G. max), and modern soybean (G. max) genotypes. We observed considerable variation in all five glycinin subunits, G1, G2 G3, G4 and G5 using proteomics and genetic analysis. Two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry (MS) analysis showed that the wild genotypes had a range of 25-29 glycinin protein spots that included both acidic and basic polypeptides followed by the ancestors with 24-28, modern cultivars with 24-25, and landraces with 17-23 protein spots. Overall, the wild genotypes have a higher number of protein spots when compared to the other three genotypes. Major variation was observed in acidic polypeptides of G3, G4 and G5 compared to G1 and G2, and minor variation was observed in basic polypeptides of all subunits. Our data indicated that there are major variations of glycinin subunits between wild and cultivated genotypes rather than within the same groups. Based on Southern blot DNA analysis, we observed genetic polymorphisms in group I genes (G1, G2, and G3) between and within the four genotype groups, but not in group II genes (G4 and G5). This is the first study reporting the comparative analysis of glycinin in a diverse set of soybean genotypes using combined proteomic and genetic analysis. 相似文献
995.
Assessment of genetic and functional diversity of phosphate solubilizing fluorescent pseudomonads isolated from rhizospheric soil 总被引:1,自引:0,他引:1
Popavath Ravindra Naik Gurusamy Raman Kannan Badri Narayanan Natarajan Sakthivel 《BMC microbiology》2008,8(1):230
Background
Phosphorus is an essential macronutrient for the growth of plants. However, in most soils a large portion of phosphorus becomes insoluble and therefore, unavailable to plants. Knowledge on biodiversity of phosphate-solubilizing fluorescent pseudomonads is essential to understand their ecological role and their utilization in sustainable agriculture. 相似文献996.
Vasudeva Ginjala Claes Holmgren Erik Uller?s Chandrasekhar Kanduri Vinod Pant Victor Lobanenkov Gary Franklin Rolf Ohlsson 《The Journal of biological chemistry》2002,277(8):5707-5710
The 5'-flank of the H19 gene harbors a differentially methylated imprinting control region that represses the maternally derived Igf2 and paternally derived H19 alleles. Here we show that the H19 imprinting control region (ICR) is a potent silencer when positioned in a promoter-proximal position. The silencing effect is not alleviated by trichostatin A treatment, suggesting that it does not involve histone deacetylase functions. When the H19 ICR is separated from the promoter by more than 1.2 +/- 0.3 kb, however, trichostatin A stimulates promoter activity 10-fold. Deletion analyses revealed that the silencing feature extended throughout the ICR segment. Finally, chromatin immunopurification analyses revealed that the H19 ICR prevented trichostatin A-dependent reacetylation of histones in the promoter region in a proximal but not in a distal position. We argue that these features are likely to be side effects of the H19 ICR, rather than explaining the mechanism of silencing of the paternal H19 allele. We issue a cautionary note, therefore, that the interpretation of insulator/silencer data could be erroneous should the distance issue not be taken into consideration. 相似文献
997.
998.
Eclipta alba L. is a well known medicinal herb, found commonly on contaminated roadsides in Kerala, India. To assess its potential for copper tolerance and accumulation, pot culture experiment was carried out. Metal accumulation in the plant in relation to 50–800 mg kg?1 Cu in soils, administered as CuSO4·7H2O in solution, was examined. Biomass yield of shoot and root, pigment content, Cu accumulation in the plant, bio-concentration factor, and translocation factor were the parameters studied. At the highest level of treatment, Cu was found accumulated more in the roots than in shoots. A significant increase in lipid peroxidation, proline content, phenolics and flavanoids were observed in Cu treated plants, compared to the control. The activity of antioxidant enzymes like superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase was found significantly changed in all the treated plants than in the control. The Bradford assay revealed a significant increase in protein content of the plant at higher levels of Cu treatment. Transmission electron microscopy, images supported the uptake and sequestration of metal particles inside the plant cell. The overall data suggests Eclipta alba L. to be a plant with high potential to tolerate Cu toxicity in soil. 相似文献
999.
Optimizing cell‐free protein expression in CHO: Assessing small molecule mass transfer effects in various reactor configurations 下载免费PDF全文
1000.
Ramya Natarajan Vandana Thathy Maria M. Mota Julius C. R. Hafalla Robert Ménard Kenneth D. Vernick 《Cellular microbiology》2001,3(6):371-379
To track malaria parasites for biological studies within the mosquito and mammalian hosts, we constructed a stably transformed clonal line of Plasmodium berghei, PbFluspo, in which sporogonic and pre‐erythrocytic liver‐stage parasites are autonomously fluorescent. A cassette containing the structural gene for the FACS‐adapted green fluorescent protein mutant 2 (GFPmut2), expressed from the 5′ and 3′ flanking sequences of the circumsporozoite (CS) protein gene, was integrated and expressed at the endogenous CS locus. Recombinant parasites, which bear a wild‐type copy of CS, generated highly fluorescent oocysts and sporozoites that invaded mosquito salivary glands and were transmitted normally to rodent hosts. The parasites infected cultured hepatocytes in vitro, where they developed into fluorescent pre‐erythrocytic forms. Mammalian cells infected by these parasites can be separated from non‐infected cells by fluorescence activated cell sorter (FACS) analysis. These fluorescent insect and mammalian stages of P. berghei should be useful for phenotypic studies in their respective hosts, as well as for identification of new genes expressed in these parasite stages. 相似文献