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Mauro Rustici Luisa Bracci Luisa Lozzi Paolo Neri Annalisa Santucci Patrizia Soldani Adriano Spreafico Neri Niccolai 《Biopolymers》1993,33(6):961-969
The glycoprotein from the neurotropic rabies virus shows a significant homology with the α neurotoxin that binds to the nicotinic acetylcholine receptor. The crystal structure of the α neurotoxins suggests that the Arg 37 guanidinium group and the Asp 31 side-chain carboxylate of the erabutoxin have stereochemical features resembling those of acetylcholine. Conformational studies on the Asn194-Ser195-Arg196-Gly197 tetrapeptide, an essential part of the binding site of the rabies virus glycoprotein, indicate that the side chains of Asn and Arg could also mimic the acetylcholine structure. This observation is consistent with the recently proposed mechanism of the viral infection. © 1993 John Wiley & Sons, Inc. 相似文献
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Andrea Schievano Barbara Scaglia Giuliana DImporzano Luca Malagutti Annalisa Gozzi Fabrizio Adani 《Bioresource technology》2009,100(23):5777-5782
This study presents an upgrading of the mathematical models to predict anaerobic biogasification potential (ABP) through quick laboratory analyses that have been presented in an earlier study. The aim is to widen the applicability of the models to heterogeneous organic substrates and to improve their reliability through a deeper statistical approach.Three multiple-step linear regressions were obtained using biomass oxygen demand in 20 h (OD20) plus the volatile solids content (VS) of 23 new samples of heterogeneous organic matrices, of 46 samples presented in the earlier work and of the data set comprising all the 69 samples. The two variables chosen were found to be suitable for very heterogeneous materials. To judge the prediction quality, a validation procedure was performed with 12 new samples using model efficiency indexes. The proposed model had good prediction ability for a large variety of organic substrates, and allows the calculation of the ABP value within only 2-day’s laboratory work instead of the 60–90 days required to obtain ABP by anaerobic test. 相似文献
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Dr. Alessandra Acquaviva Dr. Nilofar Prof. Dr. Abdelhakim Bouyahya Prof. Dr. Gokhan Zengin Dr. Simonetta Cristina Di Simone Prof. Dr. Lucia Recinella Prof. Dr. Sheila Leone Prof. Dr. Luigi Brunetti Prof. Dr. Abdullahi Ibrahim Uba Prof. Dr. Ugur Cakilcioğlu Prof. Dr. Rıdvan Polat Prof. Dr. Ekrem Darendelioglu Prof. Dr. Luigi Menghini Prof. Dr. Claudio Ferrante Dr. Maria Loreta Libero Prof. Dr. Giustino Orlando Prof. Dr. Annalisa Chiavaroli 《化学与生物多样性》2023,20(8):e202300547
Artemisia annua L. (Asteraceae Family) is an important plant in Asia that has been used for treating different diseases, including fever due to malaria, wounds, tubercolisis, scabues, pain, convulsions, diabetes, and inflammation. In this study we aimed to evaluate the effects of different polarity extracts (hexane, dichloromethane, ethyl acetate, ethanol, ethanol/water (70 %) and water) from A. annua against the burden of inflammation and oxidative stress occurring in colon tissue exposed to LPS. In parallel, chemical composition, antiradical, and enzyme inhibition effects against α-amylase, α-glucosidase, tyrosinase, and cholinesterases were evaluated. The water extract contained the highest content of the total phenolic with 34.59 mg gallic acid equivalent (GAE)/g extract, while the hexane had the highest content of the total flavonoid (20.06 mg rutin equivalent (RE)/g extract). In antioxidant assays, the polar extracts (ethanol, ethanol/water and water) exhibited stronger radical scavenging and reducing power abilities when compared to non-polar extracts. The hexane extract showed the best AChE, tyrosinase and glucosidase inhibitory effects. All extracts revealed effective anti-inflammatory agents, as demonstrated by the blunting effects on COX-2 and TNFα gene expression. These effects seemed to be not related to the only phenolic content. However, it is worthy of interest to highlight how the higher potency against LPS-induced gene expression was shown by the water extract ; thus suggesting a potential phytotherapy application in the management of clinical symptoms related to inflammatory colon diseases, although future in vivo studies are needed to confirm such in vitro and ex vivo observations. 相似文献
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Annalisa La Gatta Antonella D’Agostino Chiara Schiraldi Giuseppe Colella 《Cell Adhesion & Migration》2019,13(1):23-32
Hyaluronic acid (HA) preparations are widely used in clinical practice and recent data suggest that commercially available HA-based compounds promote ulcer re-epithelialization and induce pain relief. However, the pathophysiological basis of these effects remains poorly understood. In the present study, we investigated the biophysical, biomolecular and functional properties of a HA preparation combined with a pool of collagen precursor synthetic aminoacids, namely l-proline, l-leucine, l-lysine and glycine (Aminogam®). Hydrodynamic characterization of Aminogam® by size exclusion chromatography-triple detector array (SEC-TDA) revealed an average molecular weight in the range of 700–1700 kDa. Rheological measurements of the 1700kDa Mw lot showed a pseoudoplastic behaviour with a zero-shear viscosity (η0) equal to 90 ± 9 Pa?s at 25°C and 55 ± 6 Pa?s at 37°C. Automated time-lapse videomicroscopy studies in a fibroblast-free system demonstrated that 1% (v/v) Aminogam® significantly reduced the healing time of wounded keratinocyte monolayers. In AKGOS assays, Aminogam® stimulated cellular locomotion (chemokinesis) and directional migration (chemotaxis) of keratinocytes. Analysis of microarray data suggested that keratinocytes had a functional neuroendocrine machinery, and this was confirmed by testing the secretion of six neuroactive molecules by ELISA, namely α-MSH, β-endorphins, melatonin, substance P, cortisol, and neurotensin. Interestingly, Aminogam® regulated the production of several neuropeptides, including β-endorphins. In conclusion, our data shed light on the epithelial-dependent mechanisms that underlie the efficacy of Aminogam®, particularly in reference to wound healing and nociception. 相似文献
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Soybean rust (Phakopsora pachyrhizi) has recently invaded North America and has the potential to be the most destructive foliar disease of soybean. As part of
the response to this threat, the Integrated Aerobiology Modeling System (IAMS) was constructed to forecast the aerial movement
of this pathogen from subtropical to middle latitude portions of the continent. IAMS simulations have been conducted daily
for the past two growing seasons and integrated with information from a nationwide observation network into a decision support
system for soybean farmers. After the 2005 season, the United States Department of Agriculture reported that many millions
of United States (U.S.) soybean hectares that would have been treated for soybean rust in 2005 were not due to this decision
support system. In 2006, soybean rust appeared for the first time in the major U.S. soybean production region over 1000 km
from known areas of inoculum production. IAMS predictions of the geographical extent and timing of disease symptom expression
were well matched with subsequent observations of the disease in the field. 相似文献