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71.
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Functional Complementation of Nontoxic Mutant Binary Toxins of Bacillus sphaericus 1593M Generated by Site-Directed Mutagenesis 下载免费PDF全文
M. Shanmugavelu F. Rajamohan M. Kathirvel G. Elangovan D. H. Dean Kunthala Jayaraman 《Applied microbiology》1998,64(2):756-759
Alanine residues were substituted by site-directed mutagenesis at selected sites of the N- and C-terminal regions of the binary toxin (51- and 42-kDa peptides) of B. sphaericus 1593M, and the mutant toxins were cloned and expressed in Escherichia coli. Bioassays with mosquito larvae, using binary toxins derived from individual mutants, showed that the substitution of alanine at some sites in both the 51-kDa and the 42-kDa peptides resulted in a total loss of activity. Surprisingly, after mixing two nontoxic derivatives of the same peptide, i.e., one mutated at the N-terminal end and the other mutated at the C-terminal end of either the 51-kDa or the 42-kDa peptide, the toxicity was restored. This result indicates that the altered binary toxins can functionally complement each other by forming oligomers. 相似文献
74.
A balance between zinc uptake by ZIP (SLC39) and efflux of zinc from the cytoplasm into subcellular organelles and out of the cell by ZnT (SLC30) transporters is crucial for zinc homeostasis. It is not clear whether normal and cancerous pancreatic cells respond differently to increased extracellular zinc concentrations. Use of flow cytometry-based methods revealed that treatment with as little as 0.01 mM zinc induced significant cytotoxicity in two human ductal adenocarcinoma cell lines. In contrast, normal human pancreatic islet cells tolerated as high as 0.5 mM zinc. Insulinoma cell lines of mouse and rat origin also succumbed to high concentrations of zinc. Exposure to elevated zinc concentrations enhanced the numbers of carcinoma but not primary islet cells staining with the cell-permeable zinc-specific fluorescent dye, FluoZin-3, indicating increased zinc influx in transformed cells. Mitochondrial membrane depolarization, superoxide generation, decreased antioxidant thiols, intracellular acidosis and activation of intracellular caspases characterized zinc-induced carcinoma cell death. Only the antioxidant glutathione but not inhibitors of enzymes implicated in apoptosis or necrosis prevented zinc-induced cytotoxicity in insulinoma cells. Immunoblotting revealed that zinc treatment increased the ubiquitination of proteins in cancer cells. Importantly, zinc treatment up-regulated the expression of ZnT-1 gene in a rat insulinoma cell line and in two human ductal adenocarcinoma cell lines. These results indicate that the exposure of pancreatic cancer cells to elevated extracellular zinc concentrations can lead to cytotoxic cell death characterized by increased protein ubiquitination and up-regulation of the zinc transporter ZnT-1 gene expression. 相似文献
75.
K Manjulatha S Srinivas N Mulakayala D Rambabu M Prabhakar KM Arunasree M Alvala MV Basaveswara Rao M Pal 《Bioorganic & medicinal chemistry letters》2012,22(19):6160-6165
An improved synthesis of functionalized aurones has been accomplished via the reaction of benzofuran-3(2H)-one with a range of benzaldehydes in the presence of a mild base EDDA under ultrasound. A number of aurones were synthesized (within 5-30min) and the molecular structure of a representative compound determined by single crystal X-ray diffraction study confirmed Z-geometry of the C-C double bond present within the molecule. Some of the compounds synthesized have shown SIRT1 inhibiting as well as anti proliferative properties against two cancer cell lines in vitro. Compound 3a [(Z)-2-(5-bromo-2-hydroxybenzylidene) benzofuran-3(2H)-one] was identified as a potent inhibitor of SIRT1 (IC(50)=1μM) which showed a dose dependent increase in the acetylation of p53 resulting in induction of apoptosis. 相似文献
76.
Gayatri Jayaraman Karikalan Sinha Subodh Kumar Roy Pranita Mandal Pranab Kumar 《Plant Molecular Biology Reporter》2021,39(3):520-545
Plant Molecular Biology Reporter - Polyploidization plays an important role in the genesis of cultivated wheat (hexaploid and tetraploid) from its diploid progenitors. Thus, evolution during... 相似文献
77.
Selvaraj Jayaraman Vishnupriya Veeraraghavan Radhika Nalinakumari Sreekandan Surapaneni Krishna Mohan Sumetha Suga Deiva Suga Devakumar Kamaraj Sonaimuthu Mohandoss Ponnulakshmi Rajagopal 《Bioinformation》2020,16(11):893
Type 2 diabetes mellitus (T2DM) is linked with Glycogen synthase kinase-3 β.Therefore, it is ofinterest to document molecular docking analysis data of compounds from Justica adhatoda L with glycogen synthase kinase-3 β. We report the binding features of ethambutol, pyrazinamide, stigmasterol and vasicoline with GSK-3 β. 相似文献
78.
S. Meenakshisundaram G. Suresh R. K. Fernando K. Jenny R. Sachidanandham K. Jayaraman 《Applied microbiology and biotechnology》1997,47(5):554-559
A chemically defined medium has been developed to support the growth and the production of mosquito larvicidal factor(s)
(MLF) of Bacillus sphaericus 1593M. On the basis of the data of steady-state continuous cultures, it has been understood that acetate can serve as a sole
carbon and energy source for B. sphaericus 1593M. Utilization of acetate by B. sphaer-icus 1593M and the production of MLF are further enhanced by the addition of glutamate at low concentrations, both in steady-state
continuous as well as in total-cell-retention cultures (TCRC). A two-step TCRC procedure resulted in better biomass and MLF
production by B. sphaericus 1593M. It was also found that glutamate can serve as a carbon source as well as a growth factor in the presence of acetate
and hence is a partially substitutable carbon source.
Received: 3 January 1997 / Accepted: 31 January 1997 相似文献
79.
Tram Huynh Zhong Chen Suhong Pang Jieping Geng Tiziano Bandiera Simona Bindi Paola Vianello Fulvia Roletto Sandrine Thieffine Arturo Galvani Wayne Vaccaro Michael A. Poss George L. Trainor Matthew V. Lorenzi Marco Gottardis Lata Jayaraman Ashok V. Purandare 《Bioorganic & medicinal chemistry letters》2009,19(11):2924-2927
Design, synthesis, and SAR development led to the identification of the potent, novel, and selective pyrazole based inhibitor (7f) of Coactivator Associated Arginine Methyltransferase (CARM1). 相似文献
80.
Ferrets are widely used as animal models for studying influenza A viral pathogenesis and transmissibility. Human-adapted influenza A viruses primarily target the upper respiratory tract in humans (infection of the lower respiratory tract is observed less frequently), while in ferrets, upon intranasal inoculation both upper and lower respiratory tract are targeted. Viral tropism is governed by distribution of complex sialylated glycan receptors in various cells/tissues of the host that are specifically recognized by influenza A virus hemagglutinin (HA), a glycoprotein on viral surface. It is generally known that upper respiratory tract of humans and ferrets predominantly express α2→6 sialylated glycan receptors. However much less is known about the fine structure of these glycan receptors and their distribution in different regions of the ferret respiratory tract. In this study, we characterize distribution of glycan receptors going beyond terminal sialic acid linkage in the cranial and caudal regions of the ferret trachea (upper respiratory tract) and lung hilar region (lower respiratory tract) by multiplexing use of various plant lectins and human-adapted HAs to stain these tissue sections. Our findings show that the sialylated glycan receptors recognized by human-adapted HAs are predominantly distributed in submucosal gland of lung hilar region as a part of O-linked glycans. Our study has implications in understanding influenza A viral pathogenesis in ferrets and also in employing ferrets as animal models for developing therapeutic strategies against influenza. 相似文献