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961.
A model of Lymantria dispar development was assembled from the published literature and used to predict the period of male moth flight in the United
States. Model predictions were compared with observations made with pheromone traps in several locations throughout the United
States but especially in Virginia, West Virginia and North Carolina between 1995 and 1996. The model was found to provide
accurate and unbiased forecasts of the dates of 5%, 50% and 95% cumulative trap catch, particularly at lower elevations. In
areas of high topographic diversity (such as West Virginia), deviations between model output and observations were minimized
by basing predictions of 5% and 50% cumulative catch on minimum elevation within neighborhoods of 25–81 km2. This model of L. dispar male flight phenology can be used to time the deployment and retrieval of pheromone traps in intensive or extensive monitoring
programs. However, a better understanding of moth movement is needed to fully explain the patterns of local trap catch.
Received: 9 October 1997/Accepted: 8 December 1997 相似文献
962.
Elena S. Shubina Natalia V. Belkova Ekaterina V. Bakhmutova Evgenii V. Vorontsov Vladimir I. Bakhmutov Alexei V. Ionidis Claudio Bianchini Lorenza Marvelli Maurizio Peruzzini Lina M. Epstein 《Inorganica chimica acta》1998,280(1-2):302-307
The reactions of various proton donors (phenol, hexafluoro-2-propanol, perfluoro-2-methyl-2-propanol, monochloroacetic acid, and tetrafluoroboric acid) with the rhenium (I) hydride complex [(triphos)Re(CO)2H] (1) have been studied in dichloromethane solution by in situ IR and NMR spectroscopy. The proton donors from [(triphos)Re(CO)2H…HOR] adducts exhibiting rather strong H…H interactions. The enthalpy variations associated with the formation of the H-bonds (−ΔH = 4.4–6.0 kcal mol−1) have been determined by IR spectroscopy, while the H…H distance in the adduct [(triphos)Re(CO)2H…HOC(CF3)3] (1.83 Å) has been calculated by NMR spectroscopy through the determination of the T1min relaxation time of the Re---H proton. It has been shown that the [(triphos)Re(CO)2H…HOR] adducts are in equilibrium with the dihydrogen complex [(triphos)Re(CO)2(η2-H2)]+, which is thermodynamically more stable than any H-bond adduct. 相似文献
963.
964.
Tatiana Ismagulova Konstantin Chekanov Olga Gorelova Olga Baulina Larisa Semenova Irina Selyakh Olga Chivkunova Elena Lobakova Olga Karpova Alexei Solovchenko 《Journal of applied phycology》2018,30(5):2737-2750
We isolated a new subarctic strain Tetradesmus obliquus IPPAS S-2023 (Scenedesmaceae, Chlorophyceae) from rock baths in the White Sea. To verify its taxonomic assignment, internal transcribed spacer 2 (ITS2) of the strain was sequenced and its secondary structure was compared with predicted ITS2 secondary structures of Scenedesmaceae. The analysis of the ITS2 made it possible to assign the new strain IPPAS S-2023 to the species T. obliquus. The ultrastructural studies and energy-dispersive X-ray spectroscopy (EDX) analysis revealed a marked accumulation of vacuolar inclusions enriched in phosphorus and nitrogen (N) as well as cytoplasmiс oil bodies. Most of predicted properties of biodiesel derived from the fatty acids profile of the strain grown in the N-free medium complied with the requirements of European and American standards. The results suggest that the new subarctic strain T. obliquus IPPAS S-2023 is a promising candidate for nutrients biosequestration and for biodiesel production. In a companion paper, we assess its biomass production capability and suitability and demonstrated suitability of IPPAS S-2023 as a reference strain for studies on elevated CO2 stress effects selection of carbon dioxide-tolerant microalgae by comparison with a CO2-tolerant strain IPPAS S-2014. 相似文献
965.
966.
Yulia Filip’echeva Andrei Shelud’ko Alexei Prilipov Elizaveta Telesheva Dmitry Mokeev Andrei Burov Lilia Petrova Elena Katsy 《Folia microbiologica》2018,63(2):147-153
Azospirillum brasilense has the ability of swimming and swarming motility owing to the work of a constitutive polar flagellum and inducible lateral flagella, respectively. The interplay between these flagellar systems is poorly understood. One of the key elements of the flagellar export apparatus is the protein FlhB. Two predicted flhB genes are present in the genome of A. brasilense Sp245 (accession nos. HE577327–HE577333). Experimental evidence obtained here indicates that the chromosomal coding sequence (CDS) AZOBR_150177 (flhB1) of Sp245 is essential for the production of both types of flagella. In an flhB1::?Omegon-Km mutant, Sp245.1063, defects in polar and lateral flagellar assembly and motility were complemented by expressing the wild-type flhB1 gene from plasmid pRK415. It was found that Sp245.1063 lost the capacity for slight but statistically significant decrease in mean cell length in response to transfer from solid to liquid media, and vice versa; in the complemented mutant, this capacity was restored. It was also shown that after the acquisition of the pRK415-harbored downstream CDS AZOBR_150176, cells of Sp245 and Sp245.1063 ceased to elongate on solid media. These initial data suggest that the AZOBR_150176-encoded putative multisensory hybrid sensor histidine kinase–response regulator, in concert with FlhB1, plays a role in morphological response of azospirilla to changes in the hardness of a milieu. 相似文献
967.
Maosheng Xia Xiaowei Li Li Yang Jiaan Ren Guangfeng Sun Shuang Qi Alexei Verkhratsky Baoman Li 《Journal of neurochemistry》2018,146(1):63-75
968.
Recurrence of the R408W Mutation in the Phenylalanine Hydroxylase Locus in Europeans 总被引:8,自引:3,他引:5
Randy C. Eisensmith Alexei A. Goltsov Charles O'Neill Linda A. Tyfield Eugene I. Schwartz Alexei I. Kuzmin Svetlana S. Baranovskaya Gennady L. Tsukerman Eileen Treacy Charles R. Scriver Flemming Güttler Per Guldberg Hans G. Eiken Jaran Apold Elisabeth Svensson Eileen Naughten Seamus F. Cahalane David T. Croke Forrester Cockburn Savio L. C. Woo 《American journal of human genetics》1995,56(1):278-286
The relative frequency of the common phenylalanine hydroxylase (PAH) mutation R408W and its associations with polymorphic RFLP, VNTR, and short-tandem-repeat (STR) sites in the PAH gene were examined in many European populations and one representative North American population of defined European descent. This mutation was found to cluster in two regions: in northwest Europe among Irish and Scottish peoples, and in eastern Europe, including the Commonwealth of Independent States. This allele was significantly less frequent in intervening populations. In eastern European populations, the R408W mutation is strongly associated with RFLP haplotype 2, the three-copy VNTR allele (VNTR 3), and the 240-bp STR allele. In northwestern European populations, it is strongly associated with RFLP haplotype 1, the VNTR allele containing eight repeats (VNTR 8), and the 244-bp STR allele. An examination of the linkage between the R408W mutation and highly polymorphic RFLP, VNTR, and STR haplotypes suggests that recurrence is the most likely mechanism to account for the two different major haplotype associations of R408W in Europe. 相似文献
969.
Selection on learning performance results in the correlated evolution of sexual dimorphism in life history
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Martyna K. Zwoinska Martin I. Lind Maria Cortazar‐Chinarro Mark Ramsden Alexei A. Maklakov 《Evolution; international journal of organic evolution》2016,70(2):342-357
The evolution of learning can be constrained by trade‐offs. As male and female life histories often diverge, the relationship between learning and fitness may differ between the sexes. However, because sexes share much of their genome, intersexual genetic correlations can prevent males and females from reaching their sex‐specific optima resulting in intralocus sexual conflict (IaSC). To investigate if IaSC constraints sex‐specific evolution of learning, we selected Caenorhabditis remanei nematode females for increased or decreased olfactory learning performance and measured learning, life span (in mated and virgin worms), reproduction, and locomotory activity in both sexes. Males from downward‐selected female lines had higher locomotory activity and longer virgin life span but sired fewer progeny than males from upward‐selected female lines. In contrast, we found no effect of selection on female reproduction and downward‐selected females showed higher locomotory activity but lived shorter as virgins than upward‐selected females. Strikingly, selection on learning performance led to the reversal of sexual dimorphism in virgin life span. We thus show sex‐specific trade‐offs between learning, reproduction, and life span. Our results support the hypothesis that selection on learning performance can shape the evolution of sexually dimorphic life histories via sex‐specific genetic correlations. 相似文献
970.
Regional atmospheric CO2 inversion reveals seasonal and geographic differences in Amazon net biome exchange
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Caroline B. Alden John B. Miller Luciana V. Gatti Manuel M. Gloor Kaiyu Guan Anna M. Michalak Ingrid T. van der Laan‐Luijkx Danielle Touma Arlyn Andrews Luana S. Basso Caio S. C. Correia Lucas G. Domingues Joanna Joiner Maarten C. Krol Alexei I. Lyapustin Wouter Peters Yoichi P. Shiga Kirk Thoning Ivar R. van der Velde Thijs T. van Leeuwen Vineet Yadav Noah S. Diffenbaugh 《Global Change Biology》2016,22(10):3427-3443
Understanding tropical rainforest carbon exchange and its response to heat and drought is critical for quantifying the effects of climate change on tropical ecosystems, including global climate–carbon feedbacks. Of particular importance for the global carbon budget is net biome exchange of CO2 with the atmosphere (NBE), which represents nonfire carbon fluxes into and out of biomass and soils. Subannual and sub‐Basin Amazon NBE estimates have relied heavily on process‐based biosphere models, despite lack of model agreement with plot‐scale observations. We present a new analysis of airborne measurements that reveals monthly, regional‐scale (~1–8 × 106 km2) NBE variations. We develop a regional atmospheric CO2 inversion that provides the first analysis of geographic and temporal variability in Amazon biosphere–atmosphere carbon exchange and that is minimally influenced by biosphere model‐based first guesses of seasonal and annual mean fluxes. We find little evidence for a clear seasonal cycle in Amazon NBE but do find NBE sensitivity to aberrations from long‐term mean climate. In particular, we observe increased NBE (more carbon emitted to the atmosphere) associated with heat and drought in 2010, and correlations between wet season NBE and precipitation (negative correlation) and temperature (positive correlation). In the eastern Amazon, pulses of increased NBE persisted through 2011, suggesting legacy effects of 2010 heat and drought. We also identify regional differences in postdrought NBE that appear related to long‐term water availability. We examine satellite proxies and find evidence for higher gross primary productivity (GPP) during a pulse of increased carbon uptake in 2011, and lower GPP during a period of increased NBE in the 2010 dry season drought, but links between GPP and NBE changes are not conclusive. These results provide novel evidence of NBE sensitivity to short‐term temperature and moisture extremes in the Amazon, where monthly and sub‐Basin estimates have not been previously available. 相似文献