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211.
Prabhakaran J Underwood MD Parsey RV Arango V Majo VJ Simpson NR Van Heertum R Mann JJ Kumar JS 《Bioorganic & medicinal chemistry》2007,15(4):1802-1807
Synthesis of [18F]4-[5-(4-methylphenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl]benzenesulfonamide ([18F]celecoxib), a selective COX-2 inhibitor, is achieved via a bromide to [18F]F- exchange reaction. Synthesis of the precursor for radiolabeling was achieved from 4'-methylacetophenone in four steps with 22% overall yield. Under non-radioactive conditions, fluorination was achieved using TBAF in DMSO at 135 degrees C in 80% yield. Synthesis of [18F]celecoxib was achieved using [18F]TBAF in DMSO at 135 degrees C in 10+/-2% yield (EOS) with >99% chemical and radiochemical purities. The specific activity was 120+/-40 mCi/micromol (EOB). [18F]celecoxib was found to be stable in ethanol, however, de[18F]fluorination (6.5%) was observed after 4 h in 10% ethanol-saline solution. Rodent PET studies show bone labeling indicating in vivo de[18F]fluorination of [18F]celecoxib. PET studies in baboon indicated a lower rate of de[18F]fluorination than rat and retention of radioactivity in brain regions consistent with the known distribution of COX-2. A radiolabeling method that can generate consistent high specific activity is needed for routine human use. 相似文献
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Rene A. Desmond John W. Waterbor George R. Hallberg Ramin B. Arani 《Biometrical journal. Biometrische Zeitschrift》2001,43(4):435-445
Epidemiologists who study cancer etiology are often asked to conduct etiologic investigations of environmental agents and cancer in populations. The difficulty in estimating the effects of relevant exposures arises because environmental data are usually available only on an aggregate level, such as by county. Individual exposures to chemical agents are usually unknown, as is the joint distribution between the environmental exposure level and disease status. Frequently, some information on the cancer cases themselves is available from a disease registry which typically includes age at diagnosis, gender, and race, and these factors may require control in the analysis. An appropriate statistical model which incorporates this nested data structure is needed. This paper illustrates application of a special case of mixed model, namely hierarchical model, to the study of agricultural factors and prostate cancer in Iowa. 相似文献
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216.
Sarah L. O’Beirne Jacqueline Salit Juan L. Rodriguez-Flores Michelle R. Staudt Charbel Abi Khalil Khalid A. Fakhro Amal Robay Monica D. Ramstetter Iman K. Al-Azwani Joel A. Malek Mahmoud Zirie Amin Jayyousi Ramin Badii Ajayeb Al-Nabet Al-Marri Maria J. Chiuchiolo Alya Al-Shakaki Omar Chidiac Maey Gharbiah Abdulbari Bener Dora Stadler Neil R. Hackett Jason G. Mezey Ronald G. Crystal 《PloS one》2016,11(7)
217.
Ramin Mazaheri Nezhad Fard Mary D. Barton Michael W. Heuzenroeder 《Current microbiology》2010,60(6):400-406
Most of the bacteriophages (phages) currently reported in Enterococcus spp. belong to tailed families of bacteriophages Podoviridae, Siphoviridae, and Myoviridae. There is a little information on non-tailed bacteriophages isolated from enterococci. Samples of sewage and piggery effluents
were tested on pig and chicken isolates of Enterococcus faecalis, E. faecium and E. gallinarum for lytic phages. In addition, isolates were exposed to mitomycin C to induce lysogenic phages. Bacteriophages that were
detected were visualized by electron microscopy. Ten bacteriophages were of isometric shape with long flexible or non-flexible
tails, while one had a long head with a long flexible tail; all contained double-stranded DNA molecules. Seven Polyhedral,
filamentous, and pleomorphic-shaped phages containing DNA or RNA were also observed. The pleomorphic phages were droplet-
or lemon-shaped in morphology. This study is the first report on polyhedral phages in Enterococcus spp. of animal origin and also the first report of filamentous and pleomorphic phages in enterococci. 相似文献
218.
Linkel K. Boateng Ramin Madarshahian Yeomin Yoon Juan M. Caicedo Joseph R. V. Flora 《Journal of molecular modeling》2016,22(8):185
A probabilistic approach is proposed to estimate water permeability in a cellulose triacetate (CTA) membrane. Water transport across the membrane is simulated in reverse osmosis mode by means of non-equilibrium molecular dynamics (MD) simulations. Different membrane configurations obtained by an annealing MD simulation are considered and simulation results are analyzed by using a hierarchical Bayesian model to obtain the permeability of the different membranes. The estimated membrane permeability is used to predict full-scale water flux by means of a process-level Monte Carlo simulation. Based on the results, the parameters of the model are observed to converge within 5-ns total simulation time. The results also indicate that the use of unique structural configurations in MD simulations is essential to capture realistic membrane properties at the molecular scale. Furthermore, the predicted full-scale water flux based on the estimated permeability is within the same order of magnitude of bench-scale experimental measurement of 1.72×10?5 m/s. 相似文献
219.
Seyed Alireza Javadinia Soodabeh Shahidsales Azar Fanipakdel Mona Joudi-Mashhad Mehrane Mehramiz Sahar Talebian Mona Maftouh Ramin Mardani Seyed Mahdi Hassanian Majid Khazaei Gordon A. Ferns Amir Avan 《Journal of cellular biochemistry》2019,120(5):6833-6840
The Wnt/β-catenin pathway is an important, dysregulated pathway in several tumor types, including pancreatic ductal adenocarcinoma. Although the activation of this pathway is an important component of normal development, its aberrant activation resulting from activating or inactivating mutations in the CTNNB1 gene locus, or in the negative regulators AXIN and APC involving stabilization of β-catenin, and activation of target genes leads to a more aggressive phenotype, suggesting its potential value as a therapeutic target in the treatment of pancreatic ductal adenocarcinoma. A number of small molecule and biologic agents have now been developed for targeting this pathway. This review summarizes the current knowledge about the therapeutic potential of targeting the Wnt pathway with particular emphasis on preclinical/clinical studies in the treatment of pancreatic ductal adenocarcinoma. 相似文献
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