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61.
Mechanical activity of cells and the stress imposed on them by extracellular environment is a constant source of injury to the plasma membrane (PM). In invasive tumor cells, increased motility together with the harsh environment of the tumor stroma further increases the risk of PM injury. The impact of these stresses on tumor cell plasma membrane and mechanism by which tumor cells repair the PM damage are poorly understood. Ca2+ entry through the injured PM initiates repair of the PM. Depending on the cell type, different organelles and proteins respond to this Ca2+ entry and facilitate repair of the damaged plasma membrane. We recently identified that proteins expressed in various metastatic cancers including Ca2+-binding EF hand protein S100A11 and its binding partner annexin A2 are used by tumor cells for plasma membrane repair (PMR). Here we will discuss the involvement of S100, annexin proteins and their regulation of actin cytoskeleton, leading to PMR. Additionally, we will show that another S100 member – S100A4 accumulates at the injured PM. These findings reveal a new role for the S100 and annexin protein up regulation in metastatic cancers and identify these proteins and PMR as targets for treating metastatic cancers. 相似文献
62.
63.
Nagesh K. Tripathi Jyoti Shukla Karttik C. Biswal P. V. Lakshmana Rao 《Applied microbiology and biotechnology》2010,86(6):1795-1803
Japanese encephalitis (JE) is one of the leading causes of acute encephalopathy affecting children and adolescents in the
tropics. Optimization of media was carried out for enhanced production of recombinant JE virus envelope domain III (EDIII)
protein in Escherichia coli. Furthermore, batch and fed-batch cultivation process in E. coli was also developed in optimized medium. Expression of this protein in E. coli was induced with 1 mM isopropyl-β-thiogalactoside and yielded an insoluble protein aggregating to form inclusion bodies.
The inclusion bodies were solubilized in 8 M urea, and the protein was purified under denaturing conditions using Ni-NTA affinity
chromatography. After fed-batch cultivation, the recombinant E. coli resulted in cell dry weight and purified protein about 36.45 g l−1 and 720 mg l−1 of culture, respectively. The purity of the recombinant JE virus EDIII protein was checked by sodium dodecyl sulfate polyacrylamide
gel electrophoresis analysis, and reactivity of this protein was determined by Western blotting and ELISA with JE virus-infected
human serum samples. These results establish the application of this protein to be used for the diagnosis of JE virus infection
or for further studies in vaccine development. This process may also be suitable for the high-yield production of other recombinant
viral proteins. 相似文献
64.
Shashi Sharma Paban Kumar Dash S. R. Santhosh Jyoti Shukla Manmohan Parida P. V. Lakshmana Rao 《Molecular biotechnology》2010,45(1):49-55
Chikungunya is one of the most important emerging arboviral infections of public health significance. Due to lack of a licensed
vaccine, rapid diagnosis plays an important role in early management of patients. In this study, a QC-RT–PCR assay was developed
to quantify Chikungunya virus (CHIKV) RNA by targeting the conserved region of E1 gene. A competitor molecule containing an
internal insertion was generated, which provided a stringent control of the quantification process. The introduction of 10-fold
serially diluted competitor in each reaction was further used to determine sensitivity. The applicability of this assay for
quantification of CHIKV RNA was evaluated with human clinical samples, and the results were compared with real-time quantitative
RT–PCR. The sensitivity of this assay was estimated to be 100 RNA copies per reaction with a dynamic detection range of 102 to 1010 copies. Specificity was confirmed using closely related alpha and flaviviruses. The comparison of QC-RT–PCR result with real-time
RT–PCR revealed 100% concordance for the detection of CHIKV in clinical samples. These findings demonstrated that the reported
assay is convenient, sensitive and accurate method and has the potential usefulness for clinical diagnosis due to simultaneous
detection and quantification of CHIKV in acute-phase serum samples. 相似文献
65.
Jyoti P. Jadhav Swapnil S. Phugare Rhishikesh S. Dhanve Shekhar B. Jadhav 《Biodegradation》2010,21(3):453-463
A newly isolated novel bacterium from sediments contaminated with dyestuff was identified as Pseudomonas aeruginosa strain BCH by 16S rRNA gene sequence analysis. The bacterium was extraordinarily active and operative over a wide rage of
temperature (10–60°C) and salinity (5–6%), for decolorization of Direct Orange 39 (Orange TGLL) at optimum pH 7. This strain
was capable of decolorizing Direct Orange 39; 50 mg l−1 within 45 ± 5 min, with 93.06% decolorization, while maximally it could decolorize 1.5 g l−1 of dye within 48 h with 60% decolorization. Analytical studies as, UV–Vis spectroscopy, FTIR, HPLC were employed to confirm
the biodegradation of dye and formation of new metabolites. Induction in the activities of lignin peroxidases, DCIP reductase
as well as tyrosinase was observed, indicating the significant role of these enzymes in biodegradation of Direct Orange 39.
Toxicity studies with Phaseolus mungo and Triticum aestivum revealed the non-toxic nature of degraded metabolites. 相似文献
66.
Louis J Lorenc-Kukula K Singh V Reese J Jander G Shah J 《The Plant journal : for cell and molecular biology》2010,64(5):800-811
The green peach aphid (GPA) (Myzus persicae Sülzer) is an important sap-sucking pest of a large variety of plants, including Arabidopsis thaliana. Arabidopsis utilizes a combination of defenses that deter insects from settling on the plant, limit insect feeding and curtail insect reproduction. We demonstrate that the previously uncharacterized Arabidopsis MPL1 (MYZUS PERSICAE-INDUCED LIPASE1) gene has an important role in defense against the GPA. MPL1 expression was rapidly induced to high level in GPA-infested plants. Furthermore, the GPA population was larger on the mpl1 mutant than the wild-type (WT) plant. In contrast, constitutive over-expression of MPL1 from the Cauliflower mosaic virus 35S gene promoter curtailed the size of the GPA population. Insect settling and feeding behavior were unaffected on the mpl1 mutant. However, compared with the phloem-sap enriched petiole exudate from the WT plant, mpl1 petiole exudate was deficient in an activity that restricts insect reproduction on a synthetic diet. Furthermore, MPL1 was required for the heightened accumulation of an antibiotic activity in petiole exudate of the Arabidopsis ssi2 mutant, which exhibits enhanced resistance to GPA. These results indicate that MPL1 has an essential function in antibiosis against GPA. The MPL1 protein exhibits homology to lipases and recombinant MPL1 has lipase activity, thus suggesting that a MPL1-dependent lipid, or a product thereof, has an important role in antibiosis against GPA. 相似文献
67.
Copper has been used as a disinfectant since ancient times and recent research has demonstrated that antimicrobial copper surfaces may have practical applications in healthcare and related areas. The present study was carried out to establish the effects of temperature and pH on inactivation and sub-lethal injury of Escherichia coli in water stored in a copper vessel, to determine the operational limits of the process in terms of these variables. To investigate the effects of temperature, a bacterial suspension at pH 7.0 was stored for up to 48 h in copper vessels at 5, 15, 25 and 35°C. For pH, a bacterial suspension was stored at 30°C for up to 48 h in copper vessels at pH 6.0, 7.0, 8.0 and 9.0. Both temperature and pH had substantial effects on inactivation and injury, with the fastest inactivation observed at elevated temperature and at pH values furthest from neutrality, while the greatest amount of sub-lethal injury, manifest as sensitivity to conventional aerobic enumeration, was observed at a temperature of 35°C. These findings have important implications for the practical application of copper-based water disinfection methods, in terms of their likely efficacy under environmental conditions. 相似文献
68.
Saxena AK Rao J Chakrabarty R Saxena M Srimal RC 《Bioorganic & medicinal chemistry letters》2007,17(6):1708-1712
A series of 1-[3-(4-substituted phenylthio) propyl]-4-(substituted phenyl) piperazines has been synthesized and evaluated for hypotensive activity. The QSAR studies indicate that resonance and hydrophobic parameters of the aryl substituents are important for hypotensive activity. The similar role of resonance parameter in describing the variance of 5-HT(2A) receptor binding affinities of these compounds suggests a possible role of 5-HT(2A) receptors in mediating the hypotensive action of title compounds. 相似文献
69.
Singh J Shaik B Singh S Sikhima S Agrawal VK Khadikar PV Supuran CT 《Bioorganic & medicinal chemistry》2007,15(20):6501-6509
The first QSAR study on the activation of the human secretory isoform of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1), CA VI, with a series of amines and amino acids is reported. A large set of topological indices have been used to obtain several tri-/tetra-parametric models. We compared the CA VI activating QSAR models with those calculated for activation of the cytosolic human isozymes hCA I and hCA II. In addition, the effect of D- and L-amino acids as activators of hCA I, hCA II and of hCA VI as compared to those of structurally related biogenic amines was investigated for obtaining statistically significant and predictive QSAR equations. The obtained models are discussed using a variety of statistical parameters. The best models were obtained for hCA II activation, followed by hCA I, whereas the QSAR models for the activation of hCA VI were statistically weaker. 相似文献
70.