全文获取类型
收费全文 | 503篇 |
免费 | 42篇 |
国内免费 | 1篇 |
出版年
2022年 | 5篇 |
2021年 | 15篇 |
2020年 | 5篇 |
2019年 | 6篇 |
2018年 | 3篇 |
2017年 | 7篇 |
2016年 | 15篇 |
2015年 | 18篇 |
2014年 | 19篇 |
2013年 | 25篇 |
2012年 | 33篇 |
2011年 | 28篇 |
2010年 | 20篇 |
2009年 | 17篇 |
2008年 | 26篇 |
2007年 | 27篇 |
2006年 | 30篇 |
2005年 | 23篇 |
2004年 | 18篇 |
2003年 | 19篇 |
2002年 | 24篇 |
2001年 | 9篇 |
2000年 | 16篇 |
1999年 | 10篇 |
1998年 | 6篇 |
1997年 | 6篇 |
1996年 | 5篇 |
1995年 | 6篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1987年 | 5篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1982年 | 3篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1977年 | 6篇 |
1976年 | 9篇 |
1975年 | 6篇 |
1974年 | 8篇 |
1973年 | 3篇 |
1972年 | 3篇 |
1971年 | 4篇 |
1969年 | 4篇 |
1967年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有546条查询结果,搜索用时 15 毫秒
41.
Jean-Luc Boutry Monique Bordes Alain Février Michel Barbier 《Journal of experimental marine biology and ecology》1978,33(2):113-118
An 8-day culture was made of the marine diatom Chaetoceros simplex calcitrans Paulsen in the presence of cholesterol-4 14C. The collected cells were then introduced into a replacement medium for a new period of 8 days. The capture and metabolism of the sterol were followed and information was obtained concerning the exchanges between the cells and the medium; for this purpose, hydrocarbons and fatty acids have been analysed. Evidence for the degradation of cholesterol into acetate is established. The observed phenomena are rapid, complex, and apparently modulated at all levels of the exchanges. 相似文献
42.
43.
Drp1 mediates caspase-independent type III cell death in normal and leukemic cells 总被引:4,自引:0,他引:4 下载免费PDF全文
Bras M Yuste VJ Roué G Barbier S Sancho P Virely C Rubio M Baudet S Esquerda JE Merle-Béral H Sarfati M Susin SA 《Molecular and cellular biology》2007,27(20):7073-7088
Ligation of CD47 triggers caspase-independent programmed cell death (PCD) in normal and leukemic cells. Here, we characterize the morphological and biochemical features of this type of death and show that it displays the hallmarks of type III PCD. A molecular and biochemical approach has led us to identify a key mediator of this type of death, dynamin-related protein 1 (Drp1). CD47 ligation induces Drp1 translocation from cytosol to mitochondria, a process controlled by chymotrypsin-like serine proteases. Once in mitochondria, Drp1 provokes an impairment of the mitochondrial electron transport chain, which results in dissipation of mitochondrial transmembrane potential, reactive oxygen species generation, and a drop in ATP levels. Surprisingly, neither the activation of the most representative proapoptotic members of the Bcl-2 family, such as Bax or Bak, nor the release of apoptogenic proteins AIF (apoptosis-inducing factor), cytochrome c, endonuclease G (EndoG), Omi/HtrA2, or Smac/DIABLO from mitochondria to cytosol is observed. Responsiveness of cells to CD47 ligation increases following Drp1 overexpression, while Drp1 downregulation confers resistance to CD47-mediated death. Importantly, in B-cell chronic lymphocytic leukemia cells, mRNA levels of Drp1 strongly correlate with death sensitivity. Thus, this previously unknown mechanism controlling caspase-independent type III PCD may provide the basis for novel therapeutic approaches to overcome apoptotic avoidance in malignant cells. 相似文献
44.
45.
Letavic MA Keith JM Jablonowski JA Stocking EM Gomez LA Ly KS Miller JM Barbier AJ Bonaventure P Boggs JD Wilson SJ Miller KL Lord B McAllister HM Tognarelli DJ Wu J Abad MC Schubert C Lovenberg TW Carruthers NI 《Bioorganic & medicinal chemistry letters》2007,17(4):1047-1051
A series of novel 4-aryl-1,2,3,4-tetrahydroisoquinoline-based histamine H(3) ligands that also have serotonin reuptake transporter inhibitor activity is described. The synthesis, in vitro biological data, and select pharmacokinetic data for these novel compounds are discussed. 相似文献
46.
Vasylieva N Barnych B Meiller A Maucler C Pollegioni L Lin JS Barbier D Marinesco S 《Biosensors & bioelectronics》2011,26(10):3993-4000
Poly(ethylene glycol) diglycidyl ether (PEGDE) is widely used as an additive for cross-linking polymers bearing amine, hydroxyl, or carboxyl groups. However, the idea of using PEGDE alone for immobilizing proteins on biosensors has never been thoroughly explored. We report the successful fabrication of microelectrode biosensors based on glucose oxidase, d-amino acid oxidase, and glutamate oxidase immobilized using PEGDE. We found that biosensors made with PEGDE exhibited high sensitivity and a response time on the order of seconds, which is sufficient for observing biological processes in vivo. The enzymatic activity on these biosensors was highly stable over several months when they were stored at 4 °C, and over at least 3d at 37 °C. Glucose microelectrode biosensors implanted in the central nervous system of anesthetized rats reliably monitored changes in brain glucose levels induced by sequential administration of insulin and glucose. PEGDE provides a simple, low cost, non-toxic alternative for the preparation of in vivo microelectrode biosensors. 相似文献
47.
Hydroliquefaction of green wastes to produce fuels 总被引:1,自引:0,他引:1
Beauchet R Pinard L Kpogbemabou D Laduranty J Lemee L Lemberton JL Bataille F Magnoux P Ambles A Barbier J 《Bioresource technology》2011,102(10):6200-6207
The direct liquefaction of a biomass composed of a mixture of wastes (straw, wood and grass) was studied using Nickel Raney as catalyst and tetralin as a solvent. Tetralin allows to solubilize green waste from 330 °C at relatively low hydrogen pressure, and avoids the recondensation of the intermediate products. The green waste deoxygenation results mainly from a decarboxylation reaction. The addition of Raney Ni in the feed, increases the gas yield due to methane formation, without diminishing the yield in solvolysis oil. The catalyst hydrogenolyses the small molecules present in the light fraction. Moreover, it improves the quality of the oil by increasing the hydrogen transfer between the solvent and the solvolysis oil. As a consequence, the oxygen content decreases and the yield of oil soluble in hexane strongly increases. The catalyst allows to obtain straight long chain alkanes (C13-C26), which result from the hydrogenation of the extractives compounds of the green waste. 相似文献
48.
Compartmentalization and ultrastructural alterations induced by chromium in aquatic macrophytes 总被引:1,自引:0,他引:1
Pedro A. Mangabeira Aluane S. Ferreira Alex-Alan F. de Almeida Val��ria F. Fernandes Emerson Lucena Vania L. Souza Alberto J. dos Santos J��nior Arno H. Oliveira Marie F. Grenier-Loustalot Fr��derique Barbier Delmira C. Silva 《Biometals》2011,24(6):1017-1026
The aim of the present study was to identify the sites of accumulation of Cr in the species of macrophytes that are abundant in the Cachoeira river, namely, Alternanthera philoxeroides, Borreria scabiosoides, Polygonum ferrugineum and Eichhornia crassipes. Plants were grown in nutritive solution supplemented with 0.25 and 50 mg l?1 of CrCl3·6H2O. Samples of plant tissues were digested with HNO3/HCl in a closed-vessel microwave system and the concentrations of Cr determined using inductively-coupled plasma mass spectrometry (ICP-MS). The ultrastructure of root, stem and leaf tissue was examined using transmission electron microscopy (TEM) and secondary ion mass spectrometry (SIMS) in order to determine the sites of accumulation of Cr and to detect possible alterations in cell organelles induced by the presence of the metal. Chromium accumulated principally in the roots of the four macrophytes (8.6?C30 mg kg?1 dw), with much lower concentrations present in the stems and leaves (3.8?C8.6 and 0.01?C9.0 mg kg?1 dw, respectively). Within root tissue, Cr was present mainly in the vacuoles of parenchyma cells and cell walls of xylem and parenchyma. Alterations in the shape of the chloroplasts and nuclei were detected in A. philoxeroides and B. scabiosoides, suggesting a possible application of these aquatic plants as biomarkers from Cr contamination. 相似文献
49.
Maurice S Coroller L Debaets S Vasseur V Le Floch G Barbier G 《Journal of applied microbiology》2011,111(6):1436-1446
Aims: To predict the risk factors for building infestation by Serpula lacrymans, which is one of the most destructive fungi causing timber decay in buildings. Methods and Results: The growth rate was assessed on malt extract agar media at temperatures between 1·5 and 45°C, at water activity (aw) over the range of 0·800–0·993 and at pH ranges from 1·5 to 11·0. The radial growth rate (μ) and the lag phase (λ) were estimated from the radial growth kinetics via the plots radius vs time. These parameters were then modelled as a function of the environmental factors tested. Models derived from the cardinal model (CM) were used to fit the experimental data and allowed an estimation of the optimal and limit values for fungal growth. Optimal growth rate occurred at 20°C, at high aw level (0·993) and at a pH range between 4·0 and 6·0. The strain effect on the temperature parameters was further evaluated using 14 strains of S. lacrymans. The robustness of the temperature model was validated on data sets measured in two different wood‐based media (Quercus robur L. and Picea abies). Conclusions: The two‐step procedure of exponential model with latency followed by the CM with inflection gives reliable predictions for the growth conditions of a filamentous fungus in our study. The procedure was validated for the study of abiotic factors on the growth rate of S. lacrymans. Significance and Impact of the Study: This work describes the usefulness of evaluating the effect of physico‐chemical factors on fungal growth in predictive building mycology. Consequently, the developed mathematical models for predicting fungal growth on a macroscopic scale can be used as a tool for risk assessment of timber decay in buildings. 相似文献
50.
The evaluation of biomarkers in bodily fluids necessitates the development of robust methods to quantify proteins in a complex background, using large sets of samples. The ability to multiplex numerous analytes in a single assay expedites the process. Liquid chromatography-mass spectrometry (LC-MS) analyses performed in selected reaction monitoring (SRM) in conjunction with stable isotope dilution MS present an effective way to detect and quantify biomarker candidates in bodily fluids. The strategy presented involves an initial qualification of predefined sets of proteins in urine. The technique was applied to detect and quantify peptides in urine samples as surrogates for a few endogenous proteins. Multiplexed assays were developed to analyze proteins associated with bladder cancer; a few exogenous proteins were added as internal standards. The sample preparation and the analytical protocols were optimized to ensure reproducibility, analytical precision, and quantification limits in the low nanogram per milliliter range. Analyses were performed using known amounts of isotopically labeled peptides. Systematic replication of the measurements indicated intra-assay and inter-assay variability, with CVs in the range of 10%. The differences measured for two targeted proteins were correlated with their level of expression in the corresponding tumors using immunohistochemistry. 相似文献