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611.
Jocelyn P. Colella John Bates Santiago F. Burneo M. Alejandra Camacho Carlos Carrion Bonilla Isabel Constable Guillermo DElía Jonathan L. Dunnum Stephen Greiman Eric P. Hoberg Enrique Lessa Schuyler W. Liphardt Manuela Londoo-Gaviria Elizabeth Losos Holly L. Lutz Nict Ordez Garza A. Townsend Peterson María Laura Martin Camila C. Ribas Bruce Struminger Fernando Torres-Prez Cody W. Thompson Marcelo Weksler Joseph A. Cook 《PLoS pathogens》2021,17(6)
The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic reveals a major gap in global biosecurity infrastructure: a lack of publicly available biological samples representative across space, time, and taxonomic diversity. The shortfall, in this case for vertebrates, prevents accurate and rapid identification and monitoring of emerging pathogens and their reservoir host(s) and precludes extended investigation of ecological, evolutionary, and environmental associations that lead to human infection or spillover. Natural history museum biorepositories form the backbone of a critically needed, decentralized, global network for zoonotic pathogen surveillance, yet this infrastructure remains marginally developed, underutilized, underfunded, and disconnected from public health initiatives. Proactive detection and mitigation for emerging infectious diseases (EIDs) requires expanded biodiversity infrastructure and training (particularly in biodiverse and lower income countries) and new communication pipelines that connect biorepositories and biomedical communities. To this end, we highlight a novel adaptation of Project ECHO’s virtual community of practice model: Museums and Emerging Pathogens in the Americas (MEPA). MEPA is a virtual network aimed at fostering communication, coordination, and collaborative problem-solving among pathogen researchers, public health officials, and biorepositories in the Americas. MEPA now acts as a model of effective international, interdisciplinary collaboration that can and should be replicated in other biodiversity hotspots. We encourage deposition of wildlife specimens and associated data with public biorepositories, regardless of original collection purpose, and urge biorepositories to embrace new specimen sources, types, and uses to maximize strategic growth and utility for EID research. Taxonomically, geographically, and temporally deep biorepository archives serve as the foundation of a proactive and increasingly predictive approach to zoonotic spillover, risk assessment, and threat mitigation.
“We are not students of some subject matter, but students of problems. And problems may cut right across the borders of any subject matter or discipline.”–Karl Popper相似文献
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614.
Bizuti Matheus Ribeiro Starck Édina da Silva Fagundes Kimberly Kamila Puhle Josiano Guilherme Lima Lucas Medeiros de Oliveira Natan Rodrigues de Sousa Silva Guilherme Vinicio Silva Débora Tavares Resende e 《Molecular and cellular biochemistry》2022,477(6):1725-1737
Molecular and Cellular Biochemistry - Respiratory infections of viral origin have become the leading cause of infectious diseases in the world. In 2020, the World Health Organization (WHO) declared... 相似文献
615.
This study provides the first detailed information on the reproductive biology of the smooth butterfly ray Gymnura micrura. A total of 905 individuals were sampled, 377 of which were used for the reproductive study. Juveniles accounted for 75% of the sample, but all life cycle stages were present in the study area. The disc width at which 50% were mature (W(D50) )was estimated at 269 and 405 mm for males and females, respectively. The W(D50V) (based on the onset of vitellogenesis) was estimated at 359 mm. Uterine fecundity (mean ±s.d. = 3·8 ± 1·3; range: 1-6) was positively correlated with female size. A 3564% gain in mean wet mass was observed from egg to full-term embryo in utero. Size at birth ranged from 135 to 175 mm W(D) (19·5 to 55·0 g), with a mean of 165·1 mm W(D) (43·3 g). The embryo sex ratio was not significantly different from 1:1. The ovaries of pregnant females were undergoing vitellogenesis during gestation, with females ready to ovulate soon after parturition. Gymnura micrura may have an asynchronous reproductive cycle, with females reproducing continuously throughout the year. 相似文献
616.
Matheus T. de Groot Maarten Merkx Marc T. M. Koper 《Journal of biological inorganic chemistry》2007,12(6):761-766
Layer-by-layer assemblies of myoglobin and polystyrenesulfonate (PSS) on pyrolitic graphite have been investigated with the
goal of determining the origin of the voltammetric response of these films. From the similar midpoint potential, coverage
and electron transfer behavior compared with those of adsorbed free heme, it was concluded that the observed voltammetric
peak is due to heme adsorbed at the electrode surface. This suggests that the interactions between the pyrolitic graphite
electrode, PSS and myoglobin can result in heme release from the protein followed by heme adsorption on the electrode. 相似文献
617.
Raphaël Mheust Cindy J. Castelle Paula B. Matheus Carnevali Ibrahim F. Farag Christine He Lin-Xing Chen Yuki Amano Laura A. Hug Jillian F. Banfield 《The ISME journal》2020,14(12):2907
Currently described members of Elusimicrobia, a relatively recently defined phylum, are animal-associated and rely on fermentation. However, free-living Elusimicrobia have been detected in sediments, soils and groundwater, raising questions regarding their metabolic capacities and evolutionary relationship to animal-associated species. Here, we analyzed 94 draft-quality, non-redundant genomes, including 30 newly reconstructed genomes, from diverse animal-associated and natural environments. Genomes group into 12 clades, 10 of which previously lacked reference genomes. Groundwater-associated Elusimicrobia are predicted to be capable of heterotrophic or autotrophic lifestyles, reliant on oxygen or nitrate/nitrite-dependent respiration, or a variety of organic compounds and Rhodobacter nitrogen fixation (Rnf) complex-dependent acetogenesis with hydrogen and carbon dioxide as the substrates. Genomes from two clades of groundwater-associated Elusimicrobia often encode a new group of nitrogenase paralogs that co-occur with an extensive suite of radical S-Adenosylmethionine (SAM) proteins. We identified similar genomic loci in genomes of bacteria from the Gracilibacteria phylum and the Myxococcales order and predict that the gene clusters reduce a tetrapyrrole, possibly to form a novel cofactor. The animal-associated Elusimicrobia clades nest phylogenetically within two free-living-associated clades. Thus, we propose an evolutionary trajectory in which some Elusimicrobia adapted to animal-associated lifestyles from free-living species via genome reduction.Subject terms: Environmental microbiology, Phylogenetics 相似文献
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619.
Ramon Souza Lino Laura Souza Lagares Caio Victor Coutinho Oliveira Ciro Oliveira Queiroz Llia Lessa Teixeira Pinto Luiz Alberto Bastos Almeida Eric Simas Bonfim Clarcson Plcido Conceio dos Santos 《Journal of Exercise Nutrition & Biochemistry》2021,25(1):7
[Purpose]Sodium bicarbonate shows ergogenic potential in physical exercise and sports activities, although there is no strong evidence which performance markers show the greatest benefit from this supplement. This study evaluated the effects of sodium bicarbonate supplementation on time trial performance and time to exhaustion in athletes and sports practitioners.[Methods]A systematic review was conducted using three databases, including 17 clinical trials. Among these clinical trials, 11 were considered eligible for the meta-analysis according to the criteria for the assessment of methodological quality using the PEDro Scale. Time to exhaustion was assessed in six studies, while time trial performance was evaluated in five studies.[Results]A significant beneficial effect of supplementation on time to exhaustion was found in a random effects model (1.48; 95% confidence interval [CI], 0.49 to 2.48). There was no significant effect of supplementation on time trial performance in a fixed effects model (slope = −0.75; 95% CI, −2.04 to 0.55) relative to a placebo group.[Conclusion]Sodium bicarbonate has the potential to improve sports performance in general, especially in terms of time to exhaustion. 相似文献
620.
Scheyla D. V. S. Siqueira Miguel A. Silva-Filho Christian A. Silva Ivonete B. Araújo Acarilia E. Silva Matheus F. Fernandes-Pedrosa Anselmo G. Oliveira E. Sócrates T. Egito 《AAPS PharmSciTech》2014,15(3):612-619
The moderate heat treatment of amphotericin B (AmB) in its micellar form (M-AmB) results in superaggregates (H-AmB) that present a substantially lower toxicity and similar activity. The aim of this work was to evaluate the H-AmB behavior after a freeze-drying process. H-AmB and M-AmB micelles were evaluated before and after freeze-drying concerning their physicochemical and biological properties by spectrophotometry and activity/toxicity assay, respectively. Four concentrations of M-AmB and H-AmB were studied aiming to correlate their aggregation state and the respective biological behavior: 50 mg L?1, 5 mg L?1, 0.5 mg L?1, and 0.05 mg L?1. Then, potassium leakage and hemoglobin leakage from red blood cells were used to evaluate the acute and chronic toxicity, respectively. The efficacy of M-AmB and H-AmB formulations was assessed by potassium leakage from Candida albicans and by the broth microdilution method. After heating, in addition to an evident turbidity, a slight blueshift from 327 to 323 nm was also observed at the concentrations of 50 and 5 mg L?1 for H-AmB. Additionally, an increase in the absorbance at 323 nm at the concentration of 0.5 mg L?1 was detected. Concerning the toxicity, H-AmB caused significantly lower hemoglobin leakage than M-AmB. These results were observed for H-AmB before and after freeze-drying. However, there was no difference between H-AmB and M-AmB concerning their activity. Accordingly, the freeze-drying cycle did not show any influence on the behavior of heated formulations, highlighting the suitability of such a method to produce a new AmB product with a long shelf life and with both greater efficiency and less toxicity. 相似文献