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61.
C. Dang X. de Montaudouin J. Bald F. Jude N. Raymond L. Lanceleur I. Paul-Pont N. Caill-Milly 《Hydrobiologia》2009,630(1):139-148
Knowledge of temporal variation in nearshore Laurentian Great Lakes fish assemblages is important for understanding species–habitat
associations, how abiotic and biotic influences vary temporally, and when sampling should occur. Using spring and fall seining
data from Lake Erie beaches, we compared day and night fish assemblages and tested for differences among sampling periods.
Beaches were utilized by a diverse collection of Lake Erie basin fishes (one-third of known species). During all sampling
periods, catches were dominated by cyprinid species (53–91%), and by invertivores and planktivorous fishes. Diel differences
were detected in abundance, species richness and assemblage structure. Multivariate analyses (canonical analysis of principal
coordinates) indicated that season had a larger influence on fish assemblage structure than diel period. Given observed temporal
variation in assemblage structure, studies of Laurentian Great Lakes beach fishes should be restricted to a single time period
(e.g. day-time spring sampling), or adopt sampling designs that permit diel period and season to be included as factors in
analyses. Second, the large seasonal variation in assemblage composition combined with higher night species richness indicates
that night sampling during both spring and fall would be the most efficient and comprehensive approach for beach fish inventory.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Handling editor: J. Trexler 相似文献
62.
Tong Wang Yaguang Si Orian S. Shirihai Huiqing Si Vera Schultz Richard F. Corkey Liping Hu Jude T. Deeney Wen Guo Barbara E. Corkey 《Obesity (Silver Spring, Md.)》2010,18(8):1493-1502
It is a desirable goal to stimulate fuel oxidation in adipocytes and shift the balance toward less fuel storage and more burning. To understand this regulatory process, respiration was measured in primary rat adipocytes, mitochondria, and fat‐fed mice. Maximum O2 consumption, in vitro, was determined with a chemical uncoupler of oxidative phosphorylation (carbonylcyanide p‐trifluoromethoxyphenylhydrazone (FCCP)). The adenosine triphosphate/adenosine diphosphate (ATP/ADP) ratio was measured by luminescence. Mitochondria were localized by confocal microscopy with MitoTracker Green and their membrane potential (ΔψM) measured using tetramethylrhodamine ethyl ester perchlorate (TMRE). The effect of N‐acetylcysteine (NAC) on respiration and body composition in vivo was assessed in mice. Addition of FCCP collapsed ΔψM and decreased the ATP/ADP ratio. However, we demonstrated the same rate of adipocyte O2 consumption in the absence or presence of fuels and FCCP. Respiration was only stimulated when reactive oxygen species (ROS) were scavenged by pyruvate or NAC: other fuels or fuel combinations had little effect. Importantly, the ROS scavenging role of pyruvate was not affected by rotenone, an inhibitor of mitochondrial complex I. In addition, mice that consumed NAC exhibited increased O2 consumption and decreased body fat in vivo. These studies suggest for the first time that adipocyte O2 consumption may be inhibited by ROS, because pyruvate and NAC stimulated respiration. ROS inhibition of O2 consumption may explain the difficulty to identify effective strategies to increase fat burning in adipocytes. Stimulating fuel oxidation in adipocytes by decreasing ROS may provide a novel means to shift the balance from fuel storage to fuel burning. 相似文献
63.
Shi-Xiao Xu Dong-Fang Cai Feng-Quan Tan Yan-Ni Fang Kai-Dong Xie Jude W. Grosser Wen-Wu Guo 《Plant Cell, Tissue and Organ Culture》2014,119(3):511-522
Citrus somatic hybrids produced in the past years provide a novel opportunity to study the immediate effects of allopolyploidization on genome structure and methylation. Here, we present a first attempt to investigate the alterations in genome structure and methylation in three sets of citrus somatic allotetraploids and their diploid parents using amplified fragment length polymorphism (AFLP) and methylation-sensitive amplified polymorphism (MSAP) techniques. Our results indicate that all the allotetraploids mainly have the AFLP and MSAP banding patterns containing specific bands from both parents plus some alterations. The incidences of the AFLP polymorphic bands in allotetraploids show a range from 4.61 to 7.88 %, while from 12.50 to 15.67 % of the sites are methylated. In addition, the proportions of callus-parent-specific DNA structure and methylation alterations are much greater than those of leaf-parent-specific alterations in the somatic hybrids. Furthermore, we find that the somatic hybrids take on a greater divergence from the callus parent and a closer relationship to leaf parent in all groups of plants by dendrogram analysis based on AFLP or MSAP data. Taken together, our results suggest that somatic hybrids are very useful in elucidating the immediate changes that occur in newly synthesized allotetraploid. 相似文献
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Perera N Kourampas N Simpson IA Deraniyagala SU Bulbeck D Kamminga J Perera J Fuller DQ Szabó K Oliveira NV 《Journal of human evolution》2011,61(3):254-269
Batadomba-lena, a rockshelter in the rainforest of southwestern Sri Lanka, has yielded some of the earliest evidence of Homo sapiens in South Asia. H. sapiens foragers were present at Batadomba-lena from ca. 36,000 cal BP to the terminal Pleistocene and Holocene. Human occupation was sporadic before the global Last Glacial Maximum (LGM). Batadomba-lena’s Late Pleistocene inhabitants foraged for a broad spectrum of plant and mainly arboreal animal resources (monkeys, squirrels and abundant rainforest snails), derived from a landscape that retained equatorial rainforest cover through periods of pronounced regional aridity during the LGM. Juxtaposed hearths, palaeofloors with habitation debris, postholes, excavated pits, and animal and plant remains, including abundant Canarium nutshells, reflect intensive habitation of the rockshelter in times of monsoon intensification and biome reorganisation after ca. 16,000 cal BP. This period corresponds with further broadening of the economic spectrum, evidenced though increased contribution of squirrels, freshwater snails and Canarium nuts in the diet of the rockshelter occupants. Microliths are more abundant and morphologically diverse in the earliest, pre-LGM layer and decline markedly during intensified rockshelter use on the wane of the LGM. We propose that changing toolkits and subsistence base reflect changing foraging practices, from shorter-lived visits of highly mobile foraging bands in the period before the LGM, to intensified use of Batadomba-lena and intense foraging for diverse resources around the site during and, especially, following the LGM. Traces of ochre, marine shell beads and other objects from an 80 km-distant shore, and, possibly burials reflect symbolic practices from the outset of human presence at the rockshelter. Evidence for differentiated use of space (individual hearths, possible habitation structures) is present in LGM and terminal Pleistocene layers. The record of Batadomba-lena demonstrates that Late Pleistocene pathways to (aspects of) behavioural ‘modernity’ (composite tools, practice of symbolism and ritual, broad spectrum economy) were diverse and ecologically contingent. 相似文献
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69.
Silvia Stringhini Valentin Rousson Bharathi Viswanathan Jude Gedeon Fred Paccaud Pascal Bovet 《PloS one》2014,9(7)
Background
Low socioeconomic status (SES) is consistently associated with higher mortality in high income countries. Only few studies have assessed this association in low and middle income countries, mainly because of sparse reliable mortality data. This study explores SES differences in overall and cause-specific mortality in the Seychelles, a rapidly developing small island state in the African region.Methods
All deaths have been medically certified over more than two decades. SES and other lifestyle-related risk factors were assessed in a total of 3246 participants from three independent population-based surveys conducted in 1989, 1994 and 2004. Vital status was ascertained using linkage with vital statistics. Occupational position was the indicator of SES used in this study and was assessed with the same questions in the three surveys.Results
During a mean follow-up of 15.0 years (range 0–23 years), 523 participants died (overall mortality rate 10.8 per 1000 person-years). The main causes of death were cardiovascular disease (CVD) (219 deaths) and cancer (142 deaths). Participants in the low SES group had a higher mortality risk for overall (HR = 1.80; 95% CI: 1.24–2.62), CVD (HR = 1.95; 1.04–3.65) and non-cancer/non-CVD (HR = 2.14; 1.10–4.16) mortality compared to participants in the high SES group. Cancer mortality also tended to be patterned by SES (HR = 1.44; 0.76–2.75). Major lifestyle-related risk factors (smoking, heavy drinking, obesity, diabetes, hypertension, hypercholesterolemia) explained a small proportion of the associations between low SES and all-cause, CVD, and non-cancer/non-CVD mortality.Conclusions
In this population-based study assessing social inequalities in mortality in a country of the African region, low SES (as measured by occupational position) was strongly associated with overall, CVD and non-cancer/non-CVD mortality. Our findings support the view that the burden of non-communicable diseases may disproportionally affect people with low SES in low and middle income countries. 相似文献70.
Jude Ejikeme Obidiegwu Kerstin Flath Christiane Gebhardt 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(4):763-780