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981.
In this paper five polycentric chytrids have been described, Nowakowskiella elegans, N. profusa, Polychytrium sp., Catenaria anguillulae and Hyphochytrium catenoides. Of the five species described, N. profusa and Polychytrium sp. are new records from India. 相似文献
982.
John F Schiltz Krishna Kesari Hena R Ashar Kiran Chada 《Cell growth & differentiation》2002,13(1):39-45
The architectural factor HMGI-C is of considerable interest for its recognized roles in mammalian development and tumorigenesis. As a result, the identification of downstream target genes of HMGI-C is the present focus of active research. In vitro evidence from macrophage cell lines has previously suggested that Hmgi-c is necessary for the inducible activation of MuRantes expression. To attempt to verify this hypothesis, an in vivo analysis was performed that took advantage of the existence of the Hmgi-c null mouse strain. The ability of cells and tissues extracted from Hmgi-c null mice to express the inflammatory chemokine MuRantes was investigated. The investigation examined MuRantes expression in primary embryonic fibroblasts and fresh peritoneal macrophages after Newcastle disease virus induction and whole organs after lipopolysaccharide induction. Each of these systems clearly demonstrates that Hmgi-c is not required for the activation of MuRantes expression. 相似文献
983.
984.
Proline, an imino acid, has been well documented to be associated with the stress response induced by abiotic factors such as
drought, cold and salinity in plants and biotic factors such as bacterial and fungal attacks. However, the regulatory mechanisms
controlling proline metabolism, intercellular and intracellular transport and connections of proline to other metabolic pathways are
poorly understood. F-MATCH analysis combined with composite module analysis (CMA) revealed that the binding sites matching
matrices for O2 and OCSBF-1 were overrepresented in the promoters of differentially expressed proline metabolism genes. The
presence of MYBAS1 consensus binding sites occurring in combination with O2 and OCSBF1 in the promoters of genes of proline
biosynthesis pathway and SBF1 and GT1 consensus binding sites occurring in combination with O2 and OCSBF1 in the promoters
of proline catabolic pathway genes suggest their involvement in modulation of proline metabolism and its accumulation in plants. 相似文献
985.
986.
987.
Alluri Kiran Nair Krishna Pillay Madhavan Kotturu Sandeep Kumar Ghosh Sudip 《Biological trace element research》2020,194(2):360-367
Biological Trace Element Research - Bone is a passive storage organ for zinc, which contains about 30% of the total body zinc. However, during extreme zinc deficiency, only a small fraction of zinc... 相似文献
988.
989.
Kiran Chintakayala Laura E. Sellars Shivani S. Singh Rajesh Shahapure Ilja Westerlaken Anne S. Meyer Remus T. Dame David C. Grainger 《Nucleic acids research》2015,43(4):2282-2292
Curved DNA binding protein A (CbpA) is a co-chaperone and nucleoid associated DNA binding protein conserved in most γ-proteobacteria. Best studied in Escherichia coli, CbpA accumulates to >2500 copies per cell during periods of starvation and forms aggregates with DNA. However, the molecular basis for DNA binding is unknown; CbpA lacks motifs found in other bacterial DNA binding proteins. Here, we have used a combination of genetics and biochemistry to elucidate the mechanism of DNA recognition by CbpA. We show that CbpA interacts with the DNA minor groove. This interaction requires a highly conserved arginine side chain. Substitution of this residue, R116, with alanine, specifically disrupts DNA binding by CbpA, and its homologues from other bacteria, whilst not affecting other CbpA activities. The intracellular distribution of CbpA alters dramatically when DNA binding is negated. Hence, we provide a direct link between DNA binding and the behaviour of CbpA in cells. 相似文献
990.
Nei2 (Rv3297) is a DNA Base Excision Repair (BER) glycosylase that is essential for survival of Mycobacterium tuberculosis in primates. We show that MtbNei2 is a bifunctional glycosylase that specifically acts on oxidized pyrimidine-containing single-stranded, double-stranded, 5’/3’ fork and bubble DNA substrates. MtbNei2 possesses Uracil DNA glycosylase activity unlike E. coli Nei. Mutational studies demonstrate that Pro2 and Glu3 located in the active site are essential for glycosylase activity of MtbNei2. Mutational analysis demonstrated that an unstructured C-terminal zinc finger domain that was important for activity in E. coli Nei and Fpg, was not required for the glycosylase activity of MtbNei2. Lastly, we screened the NCI natural product compound database and identified three natural product inhibitors with IC50 values ranging between 41.8 μM-92.7 μM against MtbNei2 in in vitro inhibition assays. Surface Plasmon Resonance (SPR) experiments showed that the binding affinity of the best inhibitor, NSC31867, was 74 nM. The present results set the stage for exploiting this important target in developing new therapeutic strategies that target Mycobacterial BER. 相似文献