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排序方式: 共有1100条查询结果,搜索用时 31 毫秒
991.
Prem P. Yadav Ranjani Maurya Ashish Arora Sudhir Sinha Ram Raghubir 《Phytochemistry》2009,70(2):256-261
Three cassane diterpene hemiketals, caesalpinolide-C, caesalpinolide-D, caesalpinolide-E and one cassane furanoditerpene were isolated from Caesalpinia bonduc. The molecular structures were elucidated using NMR spectroscopy in combination with IR, UV and mass spectral data and relative stereochemistries were determined through ROESY correlation. The isolated compounds were tested for their antiproliferative activity against MCF-7 (breast adenocarcinoma), DU145 (prostate carcinoma), C33A (Cervical carcinoma) and Vero (African green monkey kidney fibroblast) cells. 相似文献
992.
Shamik Polley Sachinandan De Subhasis Batabyal Ramakant Kaushik Paras Yadav Jaspreet Singh Arora Saibal Chattopadhyay Subhransu Pan Biswajit Brahma Tirtha Kumar Datta Surender Lal Goswami 《Small Ruminant Research》2009,85(2-3):122-129
The Black Bengal is a prolific goat breed in India. Natural mutations in prolific sheep breeds have shown that the transforming growth factor beta (TGF-β) super family ligands such as growth differentiation factor 9 (GDF9), bone morphogenetic protein 15 (BMP15) and their type I receptor (bone morphogenetic protein receptor, BMPR1B) are crucial for ovulation and as well as for increasing litter size. Mutations in any of these genes increased prolificacy in sheep. Based on the known mutation information in sheep PCR primers were designed to screen known polymorphism in 88 random Black Bengal goats. Only the BMPR1B gene was polymorphic. Three genotypes of animals were detected in tested animals with mutant (FecBB) and wild type (FecB+) alleles were 0.57 and 0.43, respectively. Non-carrier, heterozygous carrier and homozygous carrier Black Bengal does had 2.7, 3.04 and 3.11 kids, respectively. All known point mutations of BMP15 and GDF9 genes were monomorphic in the animals tested. These results preliminarily showed that the BMPR1B gene might be a major gene that influences prolificacy of Black Bengal goats. 相似文献
993.
994.
Neely GG Hess A Costigan M Keene AC Goulas S Langeslag M Griffin RS Belfer I Dai F Smith SB Diatchenko L Gupta V Xia CP Amann S Kreitz S Heindl-Erdmann C Wolz S Ly CV Arora S Sarangi R Dan D Novatchkova M Rosenzweig M Gibson DG Truong D Schramek D Zoranovic T Cronin SJ Angjeli B Brune K Dietzl G Maixner W Meixner A Thomas W Pospisilik JA Alenius M Kress M Subramaniam S Garrity PA Bellen HJ Woolf CJ Penninger JM 《Cell》2010,143(4):628-638
Worldwide, acute, and chronic pain affects 20% of the adult population and represents an enormous financial and emotional burden. Using genome-wide neuronal-specific RNAi knockdown in Drosophila, we report a global screen for an innate behavior and identify hundreds of genes implicated in heat nociception, including the α2δ family calcium channel subunit straightjacket (stj). Mice mutant for the stj ortholog CACNA2D3 (α2δ3) also exhibit impaired behavioral heat pain sensitivity. In addition, in humans, α2δ3 SNP variants associate with reduced sensitivity to acute noxious heat and chronic back pain. Functional imaging in α2δ3 mutant mice revealed impaired transmission of thermal pain-evoked signals from the thalamus to higher-order pain centers. Intriguingly, in α2δ3 mutant mice, thermal pain and tactile stimulation triggered strong cross-activation, or synesthesia, of brain regions involved in vision, olfaction, and hearing. 相似文献
995.
A three-step optimization strategy, which includes a one-factor-at-a-time classical method and different statistical approaches [Plackett-Burman design and RSM (response surface methodology)], were applied to optimize the antioxidant potential of Aspergillus terreus. Antioxidant activity was assayed by different procedures and compared with TPC (total phenolic content). Primarily, different carbon and nitrogen sources were screened by classical methods, which revealed sucrose and NaNO3 to be the most suitable. The significance of the components of Czapek Dox's medium with respect to antioxidant activity was evaluated with the Plackett-Burman design, which supported sucrose and NaNO3 to be the most significant. In a second step, sucrose and NaNO3 along with temperature were further taken as three variables for RSM to study their interaction. Response surface analysis showed 4% sucrose, 0.1% NaNO3 and an incubation temperature of 30?°C to be the optimal conditions. Under these conditions, the antioxidant potential assayed through the different procedures was 88.1, 74.9 and 70.2% scavenging effect for DPPH (1,1-diphenyl-2-picryl hydrazyl) radical, ferrous ion and nitric oxide ion respectively. The reducing power showed an absorbance of 2.0 with 71.5% activity for the FRAP (ferric reducing antioxidant power) assay. TPC under different physio-chemical conditions and antioxidant potential under various assay procedures correlated positively. 相似文献
996.
Activation and nuclear translocation of PKCdelta,Pyk2 and ERK1/2 by gonadotropin releasing hormone in HEK293 cells 总被引:1,自引:0,他引:1
Farshori PQ Shah BH Arora KK Martinez-Fuentes A Catt KJ 《The Journal of steroid biochemistry and molecular biology》2003,85(2-5):337-347
The mechanism of agonist-induced activation of Pyk2 and its relationship with ERK1/2 phosphorylation was analyzed in HEK293 cells stably expressing the gonadotropin releasing hormone (GnRH) receptor. GnRH stimulation caused rapid and sustained phosphorylation of ERK1/2 and Pyk2 that was accompanied by their nuclear translocation. Pyk2 was also localized on cell membranes and at focal adhesions. Dominant negative Pyk2 (PKM) had no effect on GnRH-induced ERK1/2 phosphorylation and c-fos expression. These actions of GnRH on ERK1/2 and Pyk2 were mimicked by activation of protein kinase C (PKC) and were abolished by its inhibition. GnRH caused translocation of PKC and δ, but not of , ι and λ, to the cell membrane, as well as phosphorylation of Raf at Ser338, a major site in the activation of MEK/ERK1/2. Stimulation of HEK293 cells by EGF caused marked ERK1/2 phosphorylation that was attenuated by the selective EGFR receptor (EGF-R) kinase inhibitor, AG1478. However, GnRH-induced ERK1/2 activation was independent of EGF-R activation. These results indicate that activation of PKC is responsible for GnRH-induced phosphorylation of both ERK1/2 and Pyk2, and that Pyk2 activation does not contribute to GnRH signaling. Moreover, GnRH-induced phosphorylation of ERK1/2 and expression of c-fos in HEK293 cells is independent of Src and EGF-R transactivation, and is mediated through the PKC/Raf/MEK cascade. 相似文献
997.
998.
Savas S Azorsa DO Jarjanazi H Ibrahim-Zada I Gonzales IM Arora S Henderson MC Choi YH Briollais L Ozcelik H Tuzmen S 《PloS one》2011,6(4):e18306
Simvastatin and lovastatin are statins traditionally used for lowering serum cholesterol levels. However, there exists evidence indicating their potential chemotherapeutic characteristics in cancer. In this study, we used bioinformatic analysis of publicly available data in order to systematically identify the genes involved in resistance to cytotoxic effects of these two drugs in the NCI60 cell line panel. We used the pharmacological data available for all the NCI60 cell lines to classify simvastatin or lovastatin resistant and sensitive cell lines, respectively. Next, we performed whole-genome single marker case-control association tests for the lovastatin and simvastatin resistant and sensitive cells using their publicly available Affymetrix 125K SNP genomic data. The results were then evaluated using RNAi methodology. After correction of the p-values for multiple testing using False Discovery Rate, our results identified three genes (NRP1, COL13A1, MRPS31) and six genes (EAF2, ANK2, AKAP7, STEAP2, LPIN2, PARVB) associated with resistance to simvastatin and lovastatin, respectively. Functional validation using RNAi confirmed that silencing of EAF2 expression modulated the response of HCT-116 colon cancer cells to both statins. In summary, we have successfully utilized the publicly available data on the NCI60 cell lines to perform whole-genome association studies for simvastatin and lovastatin. Our results indicated genes involved in the cellular response to these statins and siRNA studies confirmed the role of the EAF2 in response to these drugs in HCT-116 colon cancer cells. 相似文献
999.
15-Lipoxygenase-2 protein has been reported to play an important role in normal development of prostate, lung, skin, and cornea tissues. It behaves as a suppressor of prostate cancer development by restricting cell cycle progression and implicating a possible protective role against tumor formation. On the basis of the above report, we selected 15-LOX-2 protein to study the structural classification and functional relationship with associated protein network at computational level. Sequence alignment and protein functional study shows that it contains a highly conserved LOX motif. PLAT domain with PF01477 and LH2 domain with PF00305 were successfully observed. Arachidonate 5-lipoxygenase (PDB ID: 3O8Y) was selected as a template with 42% identity. 3D structure was successfully predicted and verified. Qualitative analysis suggests that the predicted model was reliable and stable with best quality. Quantitative study shows that the model contained expected volume and area with best resolution. Predicted and best evaluated model has been successfully deposited to PMDB database with PMDB ID PM0078035. Active site identification revealed GLU(369), ALA(370), LEU(371), THR(372), HIS(373), LEU(374), HIS(376), SER(377), HIS(378), THR(385), LEU(389), HIS(394), PHE(399), LYS(400), LEU(401), ILE(403) and PRO(404) residues may play a major role during protein-protein, protein-drug and protein-cofactor interactions. STRING database result indicated that IL (4), GPX (2 and 4), PPARG, PTGS (1 and 2), CYP (2J2, 2C8, 4A11 and 2B6), PLA (2G2A, 2G4A, 2G1B and 2G6) and A LOX (5, 15, 12 and 12B) members from their respective gene families have network based functional association with 15-LOX-2. 相似文献
1000.