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211.
Costanza Casiraghi Iryna Shanina Sehyun Cho Michael L. Freeman Marcia A. Blackman Marc S. Horwitz 《PLoS pathogens》2012,8(5)
Epstein-Barr virus (EBV) has been identified as a putative environmental trigger of multiple sclerosis (MS), yet EBV''s role in MS remains elusive. We utilized murine gamma herpesvirus 68 (γHV-68), the murine homolog to EBV, to examine how infection by a virus like EBV could enhance CNS autoimmunity. Mice latently infected with γHV-68 developed more severe EAE including heightened paralysis and mortality. Similar to MS, γHV-68EAE mice developed lesions composed of CD4 and CD8 T cells, macrophages and loss of myelin in the brain and spinal cord. Further, T cells from the CNS of γHV-68 EAE mice were primarily Th1, producing heightened levels of IFN-γ and T-bet accompanied by IL-17 suppression, whereas a Th17 response was observed in uninfected EAE mice. Clearly, γHV-68 latency polarizes the adaptive immune response, directs a heightened CNS pathology following EAE induction reminiscent of human MS and portrays a novel mechanism by which EBV likely influences MS and other autoimmune diseases. 相似文献
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213.
Eragrostis tef (Zucc.) Trotter is a native Ethiopian cereal. It was recently classified into 35 cultivars which are united into 6 complexes based on inflorescence morphology, grain color, time to maturity and uses. These complexes do not show ecogeographic unity, and they cross ethnological boundaries. Thirty-nine collections of t’ef were studied in biosystematic detail, and compared withE. aethiopica Chiov. andE. pilosa (L.) Beauv., two putative ancestors of the cereal. The latter species is morphologically variable but closely allied to E. tef. Three morphologically distinct complexes are recognized within the cereal. The ethnological significance of these complexes of t’ef is not clear. 相似文献
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216.
Social Goals and the Valuation of Ecosystem Services 总被引:24,自引:0,他引:24
Robert Costanza 《Ecosystems》2000,3(1):4-10
217.
Mauro Cimino Fabio Benfenati Costanza Farabegoli Flaminio Cattabeni Luigi F. Agnati 《Journal of neurochemistry》1987,48(4):1069-1076
The phosphorylation of specific proteins in pineal homogenate was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. Cyclic AMP had the capacity to stimulate in a dose-dependent manner the incorporation of 32P in protein bands of apparent molecular weights 59K, 56K, and 35K with a maximal effect at 1 microM. On the other hand, calcium alone did not induce a marked increase in 32P incorporation with the exception of a dose-dependent phosphorylation of a 46K protein with a peak effect at 0.2 mM calcium concentration. The addition of exogenous calmodulin enhanced 32P incorporation in proteins migrating in the 62K and 52K regions, an effect that was antagonized by the calmodulin inhibitor trifluoperazine. However, also under these conditions, the stimulation of pineal protein phosphorylation was rather weak compared to that observed in other brain areas. In an attempt to investigate the functional changes of these biochemical processes during environmental lighting and adrenergic stimulation, it was found that the administration of (-)-isoproterenol (5 mg/kg, s.c.), a beta-receptor agonist, induced a clear-cut enhancement of 32P incorporation into the cyclic AMP-sensitive 59K and 56K proteins only in animals exposed for 18 h to the light, whereas it was almost ineffective in those kept in the dark for the same period. This effect was antagonized by (-)-propranolol pretreatment (20 mg/kg), suggesting that the changes in cyclic AMP-dependent protein phosphorylation observed in supersensitive pineals may represent a beta-receptor mediated process.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
218.
Daniela Lupi Serena Malabusini Silvia de Milato Alessandro Luigi Heinzl Enrico Ruzzier Luciano Bani Sara Savoldelli Costanza Jucker 《Agricultural and Forest Entomology》2023,25(4):511-521
- Psacothea hilaris hilaris is an exotic cerambycid detected in Lombardy (northern Italy) in 2005 and now established and undergoing an expansion phase. The species constitutes a serious pest for Ficus spp. and Morus spp.
- The aim of this work is to update the distribution area of the species in Italy, investigating its expansion over 16 years. Data were acquired through the authors' direct field records and community science, by data mining on national and international web platforms and social networks. Reports were analysed and GPS points plotted in ArcMap 10.8.1 to obtain distribution maps.
- Of the records collected, 34% were acquired during field surveys, 22% via e-mail and 44% through on-line forums and social networks.
- Adults of P. h. hilaris showed a long period of activity, from April to the beginning of December, with a peak of presence from June to September. The presence of the pest has been ascertained over six provinces in Lombardy covering an area estimated at more than 1750 km2 in 2021. New detections occurred within 2 km of a known infestation from the previous year in 41.6% of cases, and between 2 and 4 km away in 37.7% of cases. The mean rate of range expansion estimated from reported records was 3.17 ± 0.33 km/year from 2010 to 2021. After an initial phase of settlement, the insect is now spreading southward.
- Given the relevant phytosanitary interest that the species may have for fig plants in Italy and in the Mediterranean Basin, it is fundamental to deepen the knowledge about its flight biology, dynamics and active dispersal capabilities in order to estimate the future range expansion.
219.
We studied the effects of logging history, topography, and potential insolation on the lower-elevation limit of existing spruce-fir
forest in Great Smoky Mountains National Park (GRSM). Dummy-variable regression, analysis of variance, and classification
trees were applied to environmental data within a geographic information system framework. The effect of logging history on
the lower limit of spruce-fir depended on aspect. On north-facing slopes (270°– 90°), the presence of spruce-fir was independent
of both logging history and potential insolation. On south-facing sites (90°–270°), the elevation of spruce-fir was significantly
higher (by 122 m) in areas that had been logged historically. Classification-tree models suggested an even greater logging
effect, indicating that both the lower limit and the upper dominance zone of spruce-fir forest are, on average, nearly 200 m
higher in historically logged landscapes. Presence of spruce-fir on south aspects was also significantly related to potential
insolation, but the strength of this effect was not dependent on logging history. Classification-tree models, developed separately
using data from logged sites versus unlogged sites, were used to estimate the current area of spruce-fir forest in the park
expected under the hypothetical scenario that no spruce-fir had been logged (38,675 ha) versus the alternate scenario that
it had hall been logged (11,727 ha). At present the area of spruce-fir forest in the park is 21,242 ha. We found greater prevalence
of spruce-fir on the Tennessee side of the divide on south aspects and historically logged sites, possibly due to greater
occurrence of westerly winds and associated cloud cover. 相似文献