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991.
Several probiotic bacteria have been proposed for treatment or prevention of inflammatory bowel diseases (IBD), showing a protective effect in animal models of experimental colitis and for some of them also in human clinical trials. While most of these probiotic bacteria are isolated from the digestive tract, we recently reported that a Lactobacillus strain isolated from cheese, L. delbrueckii subsp. lactis CNRZ327 (Lb CNRZ327), also possesses anti-inflammatory effects in vitro and in vivo, demonstrating that common dairy bacteria may be useful in the treatment or prevention of IBD. Here, we studied the mechanisms underlying the protective effects of Lb CNRZ327 in vivo, in a mouse dextran sodium sulfate (DSS) colitis model. During colitis, Lb CNRZ327 modulated the production of TGF-β, IL-6, and IL-12 in colonic tissue and of TGF-β and IL-6 in the spleen, and caused an expansion of CD4+Foxp3+ regulatory T cells in the cecal lymph nodes. Moreover, a strong tendency to CD4+Foxp3+ expansion was also observed in the spleen. The results of this study for the first time show that orally administered dairy lactobacilli can not only modulate mucosal but also systemic immune responses and constitute an effective treatment of IBD.  相似文献   
992.
In aquatic ecosystems, the superimposition of mixing events to the light diel cycle exposes phytoplankton to changes in the velocity of light intensity increase, from diurnal variations to faster mixing-related ones. This is particularly true in coastal waters, where diatoms are dominant. This study aims to investigate if coastal diatoms differently activate the photoprotective responses, xanthophyll cycle (XC) and non-photochemical fluorescence quenching (NPQ), to cope with predictable light diel cycle and unpredictable mixing-related light variations. We compared the effect of two fast light intensity increases (simulating mixing events) with that of a slower increase (corresponding to the light diel cycle) on the modulation of XC and NPQ in the planktonic coastal diatom Pseudo-nitzschia multistriata. During each light treatment, the photon flux density (PFD) progressively increased from darkness to five peaks, ranging from 100 to 650 µmol photons m−2 s−1. Our results show that the diel cycle-related PFD increase strongly activates XC through the enhancement of the carotenoid biosynthesis and induces a moderate and gradual NPQ formation over the light gradient. In contrast, during mixing-related PFD increases, XC is less activated, while higher NPQ rapidly develops at moderate PFD. We observe that together with the light intensity and its increase velocity, the saturation light for photosynthesis (Ek) is a key parameter in modulating photoprotection. We propose that the capacity to adequately regulate and actuate alternative photoprotective ‘safety valves’ in response to changing velocity of light intensity increase further enhances the photophysiological flexibility of diatoms. This might be an evolutionary outcome of diatom adaptation to turbulent marine ecosystems characterized by unpredictable mixing-related light changes over the light diel cycle.  相似文献   
993.
Constructed wetlands are wastewater treatment technologies based in natural systems, and their environmental and hydraulic behaviour is influenced by weather conditions like temperature, solar radiation and precipitation. In this paper, a one-dimensional dynamic model applicable to horizontal flow constructed wetlands is presented. The structure of the hydraulic module considers Darcy's law for estimating head losses along the porous media and the boundary condition of the outlet structure. For the water budgets, precipitation and evapotranspiration are considered. The model was calibrated and validated with data from a constructed wetland operating in the South of Portugal, and a good agreement between simulated and measured data was obtained. The relevance of considering evapotranspiration in order to obtain good flow estimations was demonstrated, showing a significant influence of that variable on daily flow reductions, especially during summer months. Better simulation results were obtained when considering an evapotranspiration pattern that describes variations during the day, instead of a constant daily evapotranspiration rate.  相似文献   
994.
Cardiovascular effects of an essential oil from the aerial parts of Mentha x villosa (OEMV) were tested in rats using a combined in vivo and in vitro approach. In non-anesthetized normotensive rats, OEMV (1, 5, 10, 20, 30 mg kg(-1) body wt., i.v.) induced a significant and dose-dependent hypotension (-3 +/- 1.8%; -6 +/- 0.7%; -40 +/- 6.7%; -58 +/- 3.8%; -57 +/- 2.1%, respectively) associated with decreases in heart rate (-1 +/- 0.3%; -9 +/- 0.9%; -17 +/- 3.2%; -72 +/- 3.1%; -82 +/- 1.4%, respectively). The hypotensive and bradycardic responses evoked by OEMV were attenuated and blocke by pre-treatment of the animals with atropine (2 mg kg(-1) body wt., i.v.). In isolated rat atrial preparations, OEMV (10, 100, 300, 500 microg ml(-1)) produced concentration-related negative chronotropic and inotropic effects (IC50 value = 229 +/- 17 and 120 +/- 13 microg ml(-1), respectively). In isolated rat aortic rings, increasing concentrations of OEM (10, 100, 300, 500 microg ml(-1)) were able to antagonize the effects of phenylephrine (1 microM), prostaglandin F2alpha (10 microM) and KCl (80 mM)-induced contractions (IC50 value = 255 +/- 9, 174 +/- 4 and 165 +/- 14 microg ml(-1), respectively). The vasorelaxant activity induced by OEMV was attenuated significantly by either endothelium removal (IC50 value = 304 +/- 9 microg ml(-1)), NG-nitro L-arginine methyl ester (L-NAME) 100 microM (IC50 value=359 +/- 18 microg ml(-1)), L-NAME 300 microM (IC50 value = 488 +/- 20 microg ml(-1)) or indomethacin 10 microM (IC50 value = 334 +/- 18 microg ml(-1)). However, it was not affected by atropine 1 microM (IC50 value = 247 +/- 12 microg ml(-1)). Furthermore, the hypotensive response induced by OEMV was attenuated significantly after nitric oxide (NO) synthase blockade (L-NAME, 20 mg kg(-1) body wt., i.v.), while bradycardia was not altered. The results suggest that the hypotensive effect induced by OEMV is probably due to its direct cardiodepressant action and peripheral vasodilation, which can be attributed to both endothelium-dependent (via EDRFs, at least NO and prostacyclin) and endothelium-independent mechanisms (such as Ca2+ channel blockade).  相似文献   
995.
The diversity and genetic relationships among two accessions of tall coconut palms collected in Brazil and seven accessions introduced from different geographic regions of the world were analyzed using 25 microsatellite primers, 19 of which were polymorphic and detected between 4 and 10 alleles per locus, with an average of 6.57. The observed and expected heterozygosity ranged from 0.25 and 0.40 in the Rennell Islands Tall (RIT) accession to 0.54 and 0.62 in the Polynesian Tall (PYT) accession. The analysis of genetic structure resulted in the formation of five distinct groups. The first group was formed by the accessions Brazilian Tall—Praia do Forte (BRTPF), Brazilian Tall—Merepe (BRTMe) and West African Tall (WAT); the second group consisted of Malaysian Tall (MLT); the third group of RIT; the fourth group of Vanuatu Tall (VTT); and the fifth group of Rotuman Tall (RTMT), Tonga Tall (TONT) and PYT. The dendrogram based on the nearest-neighbor method detected the formation of two main groups and five subgroups, indicating that the genetic relationships of the accessions are based on their geographic regions of origin. The analyses revealed genetic relationships between the accessions collected in Brazil and the accession from Africa, and among palms from South East Asia and the South Pacific, confirming the common origin of these accessions. The information obtained in this study can guide decisions on germplasm conservation activities and the efficient selection of genetically divergent parents for use in coconut breeding programs in Brazil, which are attempting to select for disease resistance, mainly to lethal yellowing, among other characteristics.  相似文献   
996.
997.
Occurrence of the West Indian drywood termite, Cryptotermes brevis, is registered for the first time as established populations in Barcelona (Spain) and also additional information is given regarding a recent record from Lisbon (Portugal). This serious invasive termite pest was detected in five buildings in Barcelona, Spain and one building in Lisbon, Portugal.  相似文献   
998.
999.
AimTo review the recent evolution of spine SBRT with emphasis on single dose treatments.BackgroundRadiation treatment of spine metastases represents a challenging problem in clinical oncology, because of the high risk of inflicting damage to the spinal cord. While conventional fractionated radiation therapy still constitutes the most commonly used modality for palliative treatment, notwithstanding its efficacy in terms of palliation of pain, local tumor control has been approximately 60%. This limited effectiveness is due to previous lack of technology to precisely target the tumor while avoiding the radiosensitive spinal cord, which constitutes a dose-limiting barrier to tumor cure.Materials and methodsA thorough review of the available literature on spine SBRT has been carried out and critically assessed.ResultsStereotactic body radiotherapy (SBRT) emerges as an alternative, non-invasive high-precision approach, which allows escalation of tumor dose, while effectively sparing adjacent uninvolved organs at risk. Engaging technological advances, such as on-line Cone Beam Computed Tomography (CBCT), coupled with Dynamic Multi-Leaf Collimation (DMLC) and rapid intensity-modulated (IMRT) beam delivery, have promoted an interactive image-guided (IGRT) approach that precisely conforms treatment onto a defined target volume with a rapid dose fall-off to collateral non-target tissues, such as the spinal cord. Recent technological developments allow the use of the high-dose per fraction mode of hypofractionated SBRT for spinal oligometastatic cancer, even if only a few millimeters away from the tumor.ConclusionSingle-dose spine SBRT, now increasingly implemented, yields unprecedented outcomes of local tumor ablation and safety, provided that advanced technology is employed.  相似文献   
1000.
Bluetongue virus (BTV) is transmitted by Culicoides biting midges and causes an infectious, non-contagious disease of ruminants. It has been rapidly emerging in southern Europe since 1998. In mainland Portugal, strains of BTV belonging to three serotypes have been detected: BTV-10 (1956-1960), BTV-4 (2004-2006 and 2013) and BTV-1 (2007-2012). This paper describes the design, implementation and results of the Entomological Surveillance Programme covering mainland Portugal, between 2005 and 2010, including 5,650 caches. Culicoides imicola Kieffer was mostly found in central and southern regions of Portugal, although it was sporadically detected in northern latitudes. Its peak activity occurred in the autumn and it was active during the winter months in limited areas of the country. Obsoletus group was present at the highest densities in the north although they were found throughout the country in substantial numbers. Culicoides activity occurred all year round but peaked in the spring. A generalized linear mixed model was developed for the analysis of the environmental factors associated with activity of the species of Culicoides suspected vectors of BTV in the country. For C. imicola Kieffer, the most important variables were month, diurnal temperature range (DTR), the number of frost days (FRS) and median monthly temperature (TMP). For the Obsoletus group, the most important factors were month, diurnal temperature range (DTR), and linear and quadratic terms for median monthly temperature (TMP). The results reported can improve our understanding of climatic factors in Culicoides activity influencing their distribution and seasonal pattern.  相似文献   
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