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991.
Kirat Kumar Ganguly Sekhar Pal Shuvojit Moulik Amitava Chatterjee 《Cell Adhesion & Migration》2013,7(3):251-261
Metastasis is a combination of biological events that makes the difference between cancer and other diseases. Metastasis requires flow of erroneous but precisely coordinated basic cellular activities like cell migration–invasion, cell survival–apoptosis, cell proliferation, etc. All of these processes require efficient regulation of cell attachment and detachment, which recruit integrin receptors in this flow of events. World literatures show several aspects of interrelation of integrins and metastasis. Integrin molecules are being used as prime target to battle metastasis. In this review we are collating the observations showing importance of integrin biology in regulation of metastasis and the strategies where integrin receptors are being used as targets to regulate metastasis. 相似文献
992.
Chunmei Yang Heehyoung Lee Veronica Jove Jiehui Deng Wang Zhang Xueli Liu Stephen Forman Thanh H. Dellinger Mark Wakabayashi Hua Yu Sumanta Pal 《PloS one》2013,8(1)
Background
Several previous studies have identified a strong association between T-cell infiltration and clinical outcome in ovarian cancer. The role of B-cells remains controversial, however.Methods
Forty-nine paraffin-embedded omental specimens derived from patients with high grade epithelial ovarian cancer were assessed. Immunohistochemical analyses were performed to characterize expression of CD19+ B-cells and pSTAT3 as high (>50% positively staining cells [PSCs]) or low (<50% PSCs). The Kaplan-Meier method with log-rank test was used to determine the association between clinicopathologic parameters and overall survival (OS). A multi-variate Cox proportional hazards regression analysis including nature of debulking (primary vs secondary), histology, tumor grade, receipt of prior chemotherapy, B-cell infiltration and pSTAT3 expression was performed.Results
Median OS was 160.6 months in those patients with low B-cell expression vs 47.3 months in those with high B-cell expression (P = 0.0015). Similarly, median OS was improved in those patients with low pSTAT3 expression (160.6 vs 47.9 months, P = 0.02). In a multivariate model to predict survival, only the degree of B-cell infiltration and clinical stage were retained. pSTAT3 expression did not enter the final model, possibly be due to a high positive correlation with B-cell infiltration (r = 0.82, P<0.0001).Conclusions
Increased B-cell infiltration and pSTAT3 expression in omental tissue are associated with poorer survival. 相似文献993.
Burkholderia sp. strain SJ98 has the chemotactic activity towards nitroaromatic and chloronitroaromatic compounds. Recently our group published draft genome of strain SJ98. In this study, we further sequence and annotate the genome of stain SJ98 to exploit the potential of this bacterium. We specifically annotate its chemotaxis genes and methyl accepting chemotaxis proteins. Genome of Burkholderia sp. SJ98 was annotated using PGAAP pipeline that predicts 7,268 CDSs, 52 tRNAs and 3 rRNAs. Our analysis based on phylogenetic and comparative genomics suggest that Burkholderia sp. YI23 is closest neighbor of the strain SJ98. The genes involved in the chemotaxis of strain SJ98 were compared with genes of closely related Burkholderia strains (i.e. YI23, CCGE 1001, CCGE 1002, CCGE 1003) and with well characterized bacterium E. coli K12. It was found that strain SJ98 has 37 che genes including 19 methyl accepting chemotaxis proteins that involved in sensing of different attractants. Chemotaxis genes have been found in a cluster along with the flagellar motor proteins. We also developed a web resource that provides comprehensive information on strain SJ98 that includes all analysis data (http://crdd.osdd.net/raghava/genomesrs/burkholderia/). 相似文献
994.
Nurun Nahar Gazi Rakesh Tamang Vipin Kumar Singh Ahmed Ferdous Ajai Kumar Pathak Mugdha Singh Sharath Anugula Pandichelvam Veeraiah Subburaj Kadarkaraisamy Brijesh Kumar Yadav Alla G. Reddy Deepa Selvi Rani Syed Saleheen Qadri Lalji Singh Gyaneshwer Chaubey Kumarasamy Thangaraj 《PloS one》2013,8(10)
Human settlement and migrations along sides of Bay-of-Bengal have played a vital role in shaping the genetic landscape of Bangladesh, Eastern India and Southeast Asia. Bangladesh and Northeast India form the vital land bridge between the South and Southeast Asia. To reconstruct the population history of this region and to see whether this diverse region geographically acted as a corridor or barrier for human interaction between South Asia and Southeast Asia, we, for the first time analyzed high resolution uniparental (mtDNA and Y chromosome) and biparental autosomal genetic markers among aboriginal Bangladesh tribes currently speaking Tibeto-Burman language. All the three studied populations; Chakma, Marma and Tripura from Bangladesh showed strikingly high homogeneity among themselves and strong affinities to Northeast Indian Tibeto-Burman groups. However, they show substantially higher molecular diversity than Northeast Indian populations. Unlike Austroasiatic (Munda) speakers of India, we observed equal role of both males and females in shaping the Tibeto-Burman expansion in Southern Asia. Moreover, it is noteworthy that in admixture proportion, TB populations of Bangladesh carry substantially higher mainland Indian ancestry component than Northeast Indian Tibeto-Burmans. Largely similar expansion ages of two major paternal haplogroups (O2a and O3a3c), suggested that they arose before the differentiation of any language group and approximately at the same time. Contrary to the scenario proposed for colonization of Northeast India as male founder effect that occurred within the past 4,000 years, we suggest a significantly deep colonization of this region. Overall, our extensive analysis revealed that the population history of South Asian Tibeto-Burman speakers is more complex than it was suggested before. 相似文献
995.
The existence of a carrier-bound pathway for inorganic sulfate assimilation has been proposed in Chlorella and Escherichia coli. The possibility that the sulfonyl group of active sulfate is transferred to a specific organic acceptor to form thiosulfate ester was examined with Salmonella typhimurium LT-2. Some 11% of the radioactive products from [35S]-3′-phosphoadenosine 5′-phosphosulfate were transferred to high molecular weight compounds, and the remainder of the product is identified as free inorganic sulfite. Apparent thiosulfonate reductase activity was detected in the reaction mixtures containing S-sulfoglutathione and NADPH as conceivable substrates, but not with partially purified sulfite reductase. The former activity was attributable to the nonenzymatic reaction, sulfitolysis. Through these in vitro experiments the existence of the carrier-bound pathway was disproved. 相似文献
996.
Rajamohan R. Poondra Ratnam V. Nallamelli Chandana Lakshmi Teja Meda B.N.V. Srinivas Anushka Grover Jyotsna Muttabathula Sreedhara R. Voleti Balasubramanian Sridhar Manojit Pal Kishore V.L. Parsa 《Bioorganic & medicinal chemistry letters》2013,23(4):1104-1109
Substituted 1,4-dihydropyridines were discovered as a novel and potent series of phosphodiesterase 4 (PDE4) inhibitors. Structure–activity relationships within this series have been carried out and studies revealed that the dihydropyridine core, with indole moiety and 3,4-dimethoxybenzyl group, is a potent analogue for PDE4 inhibition. These novel series of compounds were prepared via a 3-component reaction in a single pot. In vitro biological activity, modeling studies and crystallography data are also reported. 相似文献
997.
Ali Nakhi Md. Shafiqur Rahman Sivakumar Archana Ravada Kishore G.P.K. Seerapu K. Lalith Kumar Devyani Haldar Manojit Pal 《Bioorganic & medicinal chemistry letters》2013,23(14):4195-4205
Novel pyrano[4,3-b]pyran-5(4H)-one based small molecules were designed as potential inhibitors of sirtuins (i.e., yeast sir2, a homolog of human SIRT1). Elegant synthesis of these compounds was performed via a multi-step sequence consisting of MCR, Sandmeyer type iodination, Sonogashira type coupling followed by iodocyclization and then Pd-mediated various C–C bond forming reactions. The overall strategy involved the construction of a pyran ring followed by the fused pyranone moiety and subsequent functionalization at C-8 position of the resultant core pyrano[4,3-b]pyran-5(4H)-one framework. The crystal structure analysis of a representative iodolactonized product (6d) is presented. Some of the synthesized compounds showed promising inhibitory activities when tested against yeast sir2 in vitro. The compound 6g showed dose dependent inhibition (IC50 = 78.05 μM) of yeast sir2 and good interactions with this protein in silico. 相似文献
998.
Molecular Biology Reports - The G-protein coupled estrogen receptor (GPER), a proposed tumor suppressor, relays short-term non-genomic responses in target cells and tissues. It frequently undergoes... 相似文献
999.
Mohan Rajat Kaur Tarandeep Bhat Hilal A. Khajuria Manu Pal Sikander Vyas Dhiraj 《Journal of Plant Growth Regulation》2020,39(1):205-215
Journal of Plant Growth Regulation - Mulberry (Morus spp.) is an important plant used for rearing silkworm (Bombyx mori L.). Its fruit is also used for human consumption with several medicinal... 相似文献
1000.
Garima Rana Rajesh Kumar Pathak Rohit Shukla 《Journal of biomolecular structure & dynamics》2020,38(1):124-136
AbstractBlood coagulation is a complex and dynamic process wherein the body activates its emergency mechanism to stop bleeding and wound healing via the interactions of prothrombotic and antithrombotic agents. von Willebrand factor (VWF) is a complex glycoprotein and initial component of the hemostasis pathway which serves a multipurpose role in blood coagulation process. There are reports of various plants that contain several bioactive compounds possessing properties of inducing blood coagulation directly or indirectly. In the present study, efforts have been made to identify bioactive compounds that may play a significant role in regulation of the coagulation cascade by accelerating VWF and thus enhance the hemostasis process. An antidiuretic peptide drug, Desmopressin, works on VWF and releases them in circulation. Forty-seven compounds from different plant sources were screened through molecular docking, out of which two compounds, Emodin and Peruvianoside II, showed more binding affinity than the reference drug Desmopressin. Emodin and Peruvianoside II showed binding energies ?7.2 and ?7.0?kcal/mol, respectively, when docked with VWF, whereas Desmopressin displayed less binding energy (?6.9?kcal/mol). Emodin belongs to anthraquinone from Rumex hastasus and Peruvianoside II belongs to flavanone glycosides from Thevetia peruviana. The mimicking potential of top identified molecules with respect to the drug was confirmed through simulation analysis. Besides, the molecular dynamics simulation (MDS) study (for 20?ns) showed that the Peruvianoside II protein complex was energetically more stable than Emodin protein complex. Based on the results, Peruvianoside II possesses great potential and thus may be considered for development of drugs for hemostasis. 相似文献