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981.
Setubal Rayanne Barros Sodré Elder de Oliveira Martins Thiago Bozelli Reinaldo Luiz 《Hydrobiologia》2020,847(13):2845-2862
Hydrobiologia - Quantifying the interactions between functional diversity and environmental change is important for understanding the effects of biodiversity on ecosystem processes. This study aims... 相似文献
982.
983.
Talíria Silva Lopes PhD Gutemberg Gomes Alves PhD Mariana Rodrigues Pereira PhD Jose Mauro Granjeiro PhD Paulo Emílio Corrêa Leite PhD 《Journal of cellular biochemistry》2019,120(10):16370-16378
Nanomedicine is an emerging research area which has brought new possibilities and promising applications in image, diagnosis, and treatment. Nanoparticles (NPs) for medicinal purposes can be made of several material types such as silica, carbon, different polymers, and metals as silver, copper, titanium, and gold. Gold NPs (AuNPs) are the most studied and used, mostly due to their characteristics including simple preparation, controllable size and distribution, biocompatibility, good acceptance of surface modifications, and specific surface plasmon resonance (SPR). This study reviews the scientific literature regarding the potential applications of AuNPs in the development of new diagnostic and therapeutic strategies for nanomedicine, including their biomedical use as a drug carrier, as an agent in radio and phototherapy, and bioimaging for image diagnosis. While it becomes clear that much research remains to be done to improve the use of these nanoparticles, with particular concern for safety issues, the evidence from the literature already points to the great potential of AuNPs in nanomedicine. 相似文献
984.
985.
Jssyca BandeiraCorrêa Brbara PezziniMoreira Larissa Lohmanm Lucas MachadoSulzbacher Analú BenderdosSantos Antonieta Ruiz Mirna StelaLudwig Gabriela Elisa Hirsch Cledir Santos Ilaine Teresinha SeibelGehrke Thiago GomesHeck 《化学与生物多样性》2019,16(1)
Schinus lentiscifolius Marchand has been used in folk medicine to treat immunoinflammatory related diseases, which are marked by OS and altered HSR. Our study aimed to evaluate OS and HSR in lymphocytes treated with S. lentiscifolius bark extracts. S. lentiscifolius barks were partitioned with solvents to obtain hexane (SL‐HEX), ethyl acetate (SL‐ACOET) and methanol (SL‐MEOH) extracts, and the presence of bioactive compounds was evaluated by thin layer chromatography. Total phenols were measured by the Folin–Ciocalteu method and flavonoids were identified by HPLC‐DAD‐ESI‐MS/MS. Antioxidant capacity was verified by DPPH method, cell viability by Trypan Blue method, lipid peroxidation by TBARS and HSP70 by immunoblotting. The SL‐ACOET extract presented higher content of phenolic compounds and antioxidant activity in vitro. It was able to reduce lipid peroxidation levels in lymphocytes induced by H2O2 and improved cell viability. The SL‐ACOET extract inhibited HSR by a decrease in both intracellular content and release of 70 kDa heat shock proteins (HSP70) and also by decrease extra‐to‐intracellular HSP70 ratio in lymphocytes submitted to heat shock (2 h, 41 °C). S. lentiscifolius bark extract has antioxidant activity and inhibitory effect on HSR probably due to the presence of polyphenols as the flavonoids quercetin and kaempferol. 相似文献
986.
987.
Thiago Olitta Basso Marcelo Goulart Dario Aldo Tonso Boris Ugarte Stambuk Andreas Karoly Gombert 《Biotechnology letters》2010,32(7):973-977
A combination of chemostat cultivation and a defined medium was used to demonstrate that uracil limitation leads to a drastic alteration in the physiology of auxotrophic cells of Saccharomyces cerevisiae. Under this condition, the carbon source is dissimilated mainly to ethanol and acetate, even in fully aerobic cultures grown at 0.1 h?1, which is far below the critical dilution rate. Differently from nitrogen-, sulphur-, or phosphate-limited cultures, uracil limitation leads to residual sugar (either glucose or sucrose) concentrations below 2 mM, which characterizes a situation of double-limitation: by the carbon source and by uracil. Furthermore, the specific rates of CO2 production and O2 consumption are increased when compared to the corresponding prototrophic strain. We conclude that when auxotrophic strains are to be used for quantitative physiological studies, special attention must be paid to the cultivation conditions, mainly regarding medium formulation, in order to avoid limitation of growth by the auxotrophic nutrient. 相似文献
988.
An evolutionary tolerance model explaining spatial patterns in species richness under environmental gradients and geometric constraints 总被引:1,自引:0,他引:1
In this study, we developed a simulation model based on the ecological and evolutionary dynamics of geographical ranges, to understand the role of species' environmental tolerances and the strength of the environmental gradient in determining spatial patterns in species richness. Using an one-dimensional space, we present the model and dissect its parameters. Also, we test the ability of the model to simulate richness in complex two-dimensional domains and to fit real patterns in species richness, using South American Tyrannidae as an example. We found that a mid-spatial peak in species richness arises spontaneously under conditions of high environmental tolerances and/or a weak environmental gradient, since this condition causes wide species' geographic ranges, which are constrained by domain's boundary and tend to overlap in the middle. Our model was also a good predictor of real patterns in species richness, especially under conditions of high environmental strength and small species' tolerance. We conclude that this kind of spatial simulation models based on species' physiological tolerance may be an important tool to understand the evolutionary dynamics of species' geographic ranges and in spatial patterns of species richness. 相似文献
989.
Juliane Guimar?es Carvalho Aline de Lima Leite Camila Peres-Buzalaf Fernanda Salvato Carlos Alberto Labate Eric T. Everett Gary Milton Whitford Marília Afonso Rabelo Buzalaf 《PloS one》2013,8(1)
A/J and 129P3/J mouse strains have different susceptibilities to dental fluorosis due to their genetic backgrounds. They also differ with respect to several features of fluoride (F) metabolism and metabolic handling of water. This study was done to determine whether differences in F metabolism could be explained by diversities in the profile of protein expression in kidneys. Weanling, male A/J mice (susceptible to dental fluorosis, n = 18) and 129P3/J mice (resistant, n = 18) were housed in pairs and assigned to three groups given low-F food and drinking water containing 0, 10 or 50 ppm [F] for 7 weeks. Renal proteome profiles were examined using 2D-PAGE and LC-MS/MS. Quantitative intensity analysis detected between A/J and 129P3/J strains 122, 126 and 134 spots differentially expressed in the groups receiving 0, 10 and 50 ppmF, respectively. From these, 25, 30 and 32, respectively, were successfully identified. Most of the proteins were related to metabolic and cellular processes, followed by response to stimuli, development and regulation of cellular processes. In F-treated groups, PDZK-1, a protein involved in the regulation of renal tubular reabsorption capacity was down-modulated in the kidney of 129P3/J mice. A/J and 129P3/J mice exhibited 11 and 3 exclusive proteins, respectively, regardless of F exposure. In conclusion, proteomic analysis was able to identify proteins potentially involved in metabolic handling of F and water that are differentially expressed or even not expressed in the strains evaluated. This can contribute to understanding the molecular mechanisms underlying genetic susceptibility to dental fluorosis, by indicating key-proteins that should be better addressed in future studies. 相似文献
990.
Daniela Leite Jabes Ana Claudia de Freitas Oliveira Valquíria Campos Alencar Fabiano Bezerra Menegidio Débora Liliane Souza Reno Daiene Souza Santos David Aciole Barbosa Renata Ozelami Vilas Boas Rodrigo Luiz de Oliveira Rodrigues Cunha Tiago Rodrigues Regina Costa de Oliveira Luiz R. Nunes 《Molecular genetics and genomics : MGG》2016,291(3):1347-1362