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991.
Varela-Ramirez A Costanzo M Carrasco YP Pannell KH Aguilera RJ 《Cell biology and toxicology》2011,27(3):159-168
In this report, we have tested the cytotoxicity of two organotin (OT) compounds by flow cytometry on a panel of immortalized
cancer cell lines of human and murine origin. Although the OT compounds exhibited varying levels of cytotoxicity, diphenylmethyltin
chloride was more toxic than 1,4-bis (diphenylchlorostannyl)p-xylene on all cell lines tested. The OT compounds were found to be highly cytotoxic to lymphoma cell lines with lower toxicity
toward the HeLa cervical cancer cell line. In order to discern the mechanism by which cell death was induced, additional experiments
were conducted to monitor characteristic changes consistent with apoptosis and/or necrosis. Cell lines treated with the experimental
compounds indicated that there was no consistent mode of cell death induction. However, both compounds induced apoptosis in
the pro-B lymphocyte cell line, NFS-70. The work presented here also demonstrates that the two OT compounds possess selective
cytotoxicity against distinct transformed cell lines. 相似文献
992.
Moraes J Arreola R Cabrera N Saramago L Freitas D Masuda A da Silva Vaz I Tuena de Gomez-Puyou M Perez-Montfort R Gomez-Puyou A Logullo C 《Insect biochemistry and molecular biology》2011,41(6):400-409
Triosephosphate isomerase (TIM) is an enzyme with a role in glycolysis and gluconeogenesis by catalyzing the interconversion between glyceraldehyde 3-phosphate and dihydroxyacetone phosphate. This enzyme has been used as a target in endoparasite drug development. In this work we cloned, expressed, purified and studied kinetic and structural characteristics of TIM from tick embryos, Rhipicephalus (Boophilus) microplus (BmTIM). The Km and Vmax of the recombinant BmTIM with glyceraldehyde 3-phosphate as substrate, were 0.47 mM and 6031 ??mol min−1 mg protein−1, respectively. The resolution of the diffracted crystal was estimated to be 2.4 Å and the overall data showed that BmTIM is similar to other reported dimeric TIMs. However, we found that, in comparison to other TIMs, BmTIM has the highest content of cysteine residues (nine cysteine residues per monomer). Only two cysteines could make disulfide bonds in monomers of BmTIM. Furthermore, BmTIM was highly sensitive to the action of the thiol reagents dithionitrobenzoic acid and methyl methane thiosulfonate, suggesting that there are five cysteines exposed in each dimer and that these residues could be employed in the development of species-specific inhibitors. 相似文献
993.
Sála M De Palma AM Hřebabecký H Dejmek M Dračínský M Leyssen P Neyts J Mertlíková-Kaiserová H Nencka R 《Bioorganic & medicinal chemistry letters》2011,21(14):4271-4275
Coxsackievirus and related enteroviruses are important human pathogens that cause various diseases with clinical manifestations ranging from trivial flu-like syndromes to dangerous or even fatal diseases such as myocarditis, meningitis and encephalitis. Here, we report on our continuous SAR study focused on 9-(bicyclo[2.2.1]hept-2-yl)-9H-purines as anti-enteroviral inhibitors. The purine moiety was modified at positions 2, 6 and 8. Several analogues inhibited Coxsackievirus B3 as well as other enteroviruses at low-micromolar concentrations. The 6-chloropurine derivative was confirmed as the most active compound in this series. 相似文献
994.
Crude glycerol (CG), a by-product of biodiesel production, is an organic carbon-rich substrate with potential as feedstock for polyhydroxyalkanoate (PHA) production. PHA is a biodegradable thermoplastic synthesized by microorganisms as an intracellular granule. In this study we investigated PHA production on CG using mixed microbial consortia (MMC) and determined that the enriched MMC produced exclusively polyhydroxybutyrate (PHB) utilizing the methanol fraction. PHB synthesis appeared to be stimulated by a macronutrient deficiency. Intracellular concentrations remained relatively constant over an operational cycle, with microbial growth occurring concurrent with polymer synthesis. PHB average molecular weights ranged from 200-380 kDa, while thermal properties compared well with commercial PHB. The resulting PHB material properties and characteristics would be suitable for many commercial uses. Considering full-scale process application, it was estimated that a 38 million L (10 million gallon) per year biodiesel operation could potentially produce up to 19 metric ton (20.9t on) of PHB per year. 相似文献
995.
Zimic M Gutiérrez AH Gilman RH López C Quiliano M Evangelista W Gonzales A García HH Sheen P 《Bioinformation》2011,6(7):271-274
Cysticercosis is a public health problem in several developing countries. The oncosphere protein TSOL18 is the most immunogenic and protective antigen ever reported against porcine cysticercosis, although no specific epitope has been identified to account for these properties. Recent evidence suggests that protection might be associated with conformational epitopes. Linear epitopes from TSOL18 were computationally predicted and evaluated for immunogenicity and protection against porcine cysticercosis. A synthetic peptide was designed based on predicted linear B cell and T cell epitopes that are exposed on the surface of the theoretically modeled structure of TSOL18. Three surface epitopes from TSOL18 were predicted as immunogenic. A peptide comprising a linear arrangement of these epitopes was chemically synthesized. The capacity of the synthetic peptide to protect pigs against an oral challenge with Taenia solium proglottids was tested in a vaccine trial. The synthetic peptide was able to produce IgG antibodies in pigs and was associated to a reduction of the number of cysts, although was not able to provide complete protection, defined as the complete absence of cysts in necropsy. This study demonstrated that B cell and T cell predicted epitopes from TSOL18 were not able to completely protect pigs against an oral challenge with Taenia solium proglottids. Therefore, other linear epitopes or eventually conformational epitopes may be responsible for the protection conferred by TSOL18. 相似文献
996.
997.
Vicinanza M Di Campli A Polishchuk E Santoro M Di Tullio G Godi A Levtchenko E De Leo MG Polishchuk R Sandoval L Marzolo MP De Matteis MA 《The EMBO journal》2011,30(24):4970-4985
Mutations in the phosphatidylinositol 4,5-bisphosphate (PtdIns4,5P(2)) 5-phosphatase OCRL cause Lowe syndrome, which is characterised by congenital cataracts, central hypotonia, and renal proximal tubular dysfunction. Previous studies have shown that OCRL interacts with components of the endosomal machinery; however, its role in endocytosis, and thus the pathogenic mechanisms of Lowe syndrome, have remained elusive. Here, we show that via its 5-phosphatase activity, OCRL controls early endosome (EE) function. OCRL depletion impairs the recycling of multiple classes of receptors, including megalin (which mediates protein reabsorption in the kidney) that are retained in engorged EEs. These trafficking defects are caused by ectopic accumulation of PtdIns4,5P(2) in EEs, which in turn induces an N-WASP-dependent increase in endosomal F-actin. Our data provide a molecular explanation for renal proximal tubular dysfunction in Lowe syndrome and highlight that tight control of PtdIns4,5P(2) and F-actin at the EEs is essential for exporting cargoes that transit this compartment. 相似文献
998.
Comparison of the biochemical and molecular properties of myoglobins from three Biomphalaria species
Kádima N. Teixeira Jamil S. Oliveira Karyne N. Souza Juliana de Moura Cristiane A. Brito Teofânia H.D.A. Vidigal Alexandre M.C. Santos Marcelo M. Santoro 《Biochemical Systematics and Ecology》2011,39(4-6):581-586
Myoglobin is a globin with heme as prosthetic group whose main known biological role is to bind to O2 reversibly. On account of their large diversity, globins from mollusks have contributed to the study of this protein class. The cDNA of the myoglobins from Biomphalaria straminea and Biomphalaria tenagophila, which have a glutamine as distal residue (E7), were constructed and analyzed by bioinformatic tools. Native (not recombinant) myoglobins of these two Biomphalaria species were purified and their experimental molecular mass (about 16 kDa) and pI (about (8.0) were provided. Data analysis showed that these proteins are monomers with the signature for the classic myoglobin fold and they are blocked in amino terminus probably by an acetyl group. Values of the autoxidation rates showed that these myoglobins oxidized slowly. About the primary sequences of the myoglobins, they turned out to be satisfactory to group mollusks in phylogenetic class. 相似文献
999.
Celine Justino Ana Gabriela Marques Dina Rodrigues Lurdes Silva Armando Costa Duarte Teresa Rocha-Santos Ana Cristina Freitas 《Biodegradation》2011,22(2):267-274
Pulp and paper mills generate pollutants associated to their effluents depending upon the type of process, type of the wood
materials, process technology applied, management practices, internal recirculation of the effluent for recovery, the amount
of water used in the industrial process and type of secondary treatment. This study is the first that reports a simultaneous
evaluation of the effects of tertiary treatments by fungi (Rhizopus oryzae and Pleurotus sajor caju), by enzyme (laccase) and by an oxidation process (photo-Fenton) on individual phenols (vanillin, guaiacol, phloroglucinol,
vanillic acid and syringic acid) of a Eucalyptus globulus bleached kraft pulp and paper mill final effluent after secondary treatment (BKPME). The tertiary treatments were applied
on BKPME samples and in BKPME samples supplemented with extra concentration of each phenol. Tertiary treatments by Rhizopus oryzae and photo-Fenton oxidation were able of complete removal (100%) of phenols on BKPME samples whereas P. sajor caju and laccase were able of 60–85% removal. On BKPME samples with added concentration of each phenol, photo-Fenton was the only
treatment capable of total phenols removal (100%), which suggests a great potential for its application. 相似文献
1000.
Gl��ria Pinto S��nia Silva Jo?o Loureiro Armando Costa Maria Celeste Dias Clara Ara��jo Lucinda Neves Concei??o Santos 《Trees - Structure and Function》2011,25(3):383-392
This paper reports the complete process from secondary emblings (SE-derived plants) regeneration to acclimatization of Eucalyptus globulus and describes histocytological changes that occur in leaves from in vitro to ex vitro acclimatization for a 3-month period.
After elongation, plants were transferred to pots with sterilized peat:perlite and acclimatized in a phytotron, with progressive
reduction of RH and increase of light intensity. Histocytological analyses were performed in fixed material using light microscopy
and ultrastructural changes followed by electron microscopy (SEM and TEM). The protocol used allowed the successful acclimatization
of the emblings. Plants looked morphologically normal and FCM screening revealed no ploidy or DNA content abnormalities. Histocytological
analyses showed significant changes along time, mostly in stomata shape and aperture, starch reserves, chloroplast morphology
and mesophyll differentiation. This is the first report concerning emblings acclimatization to ex vitro conditions in Eucalyptus. It was clearly demonstrated that during acclimatization emblings suffered profound changes in leaf morphology in order to
successfully adapt to ex vitro conditions. 相似文献