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931.
Predicting species distributions across the Amazonian and Andean regions using remote sensing data 总被引:3,自引:1,他引:2
Wolfgang Buermann Sassan Saatchi Thomas B. Smith Brian R. Zutta Jaime A. Chaves Borja Milá Catherine H. Graham 《Journal of Biogeography》2008,35(7):1160-1176
Aim We explore the utility of newly available optical and microwave remote sensing data from the Moderate Resolution Imaging Spectroradiometer (MODIS) and QuikSCAT (QSCAT) instruments for species distribution modelling at regional to continental scales. Using eight Neotropical species from three taxonomic groups, we assess the extent to which remote sensing data can improve predictions of their geographic distributions. For two bird species, we investigate the specific contributions of different types of remote sensing variables to the predictions and model accuracy at the regional scale, where the benefits of the MODIS and QSCAT satellite data are expected to be most significant. Location South America, with a focus on the tropical and subtropical Andes and the Amazon Basin. Methods Potential geographic distributions of eight species, namely two birds, two mammals and four trees, were modelled with the maxent algorithm at 1‐km resolution over the South American continent using climatic and remote sensing data separately and combined. For each species and model scenario, we assess model performance by testing the agreement between observed and simulated distributions across all thresholds and, in the case of the two focal bird species, at selected thresholds. Results Quantitative performance tests showed that models built with remote sensing and climatic layers in isolation performed well in predicting species distributions, suggesting that each of these data sets contains useful information. However, predictions created with a combination of remote sensing and climatic layers generally resulted in the best model performance across the three taxonomic groups. In Ecuador, the inclusion of remote sensing data was critical in resolving the known geographically isolated populations of the two focal bird species along the steep Amazonian–Andean elevational gradients. Within remote sensing subsets, microwave‐based data were more important than optical data in the predictions of the two bird species. Main conclusions Our results suggest that the newly available remote sensing data (MODIS and QSCAT) have considerable utility in modelling the contemporary geographical distributions of species at both regional and continental scales and in predicting range shifts as a result of large‐scale land‐use change. 相似文献
932.
The purpose of the present study was to analyse men's basketball competitions, trying to identify which game-related statistics allow to discriminate winning and losing teams. The sample used corresponded to 306 games from the 2004-2005 Regular Season of the Spanish Men's Professional League. The game-related statistics gathered were: 2 and 3 points field-goals (both successful and unsuccessful), free-throws (both successful and unsuccessful), offensive and defensive rebounds, blocks, assists, fouls, turnovers and steals. The data were analysed in two groups: balanced games (final score differences equal or below 12 points) and unbalanced games (final score differences above 12 points). Discriminant analysis allowed to conclude the following: (i) in balanced games, the variable that best differentiate both groups were the defensive rebounds; (ii) in unbalanced games, the variables that discriminate between both groups were the successful 2 points field-goals, the defensive rebounds and the assists; and (iii) in all games, the statistical analysis identified two variables that discriminate winning and losing teams (defensive rebounds and assists). The defensive rebounds were the only game-related statistic that discriminates both groups in all performed analysis. Coaches and players should be aware of these different profiles in order to increase knowledge about game cognitive and motor solicitation and, therefore, to enhance specificity at the time of practice and game planning. 相似文献
933.
Jaime Esteban Nieves Z Martín-de-Hijas Teemu J Kinnari Guillermo Ayala Ricardo Fernández-Roblas Ignacio Gadea 《BMC microbiology》2008,8(1):184
Background
A study to evaluate the biofilm-development ability in three different media (Middlebrook 7H9, sterile tap water and PBS-5% glucose) was performed with 19 collection strains from 15 different species on non-pigmented rapidly growing mycobacteria (NPRGM). A microtiter plate assay was developed to evaluate the percentage of covered surface of the microtiter plate wells in different days from day 1 to day 69. 相似文献934.
Antonio Naranjo Tuulikki Sokka Miguel A Descalzo Jaime Calvo-Alén Kim H?rslev-Petersen Reijo K Luukkainen Bernard Combe Gerd R Burmester Joe Devlin Gianfranco Ferraccioli Alessia Morelli Monique Hoekstra Maria Majdan Stefan Sadkiewicz Miguel Belmonte Ann-Carin Holmqvist Ernest Choy Recep Tunc Aleksander Dimic Martin Bergman Sergio Toloza Theodore Pincus the QUEST-RA Group 《Arthritis research & therapy》2008,10(2):R30
Introduction
We analyzed the prevalence of cardiovascular (CV) disease in patients with rheumatoid arthritis (RA) and its association with traditional CV risk factors, clinical features of RA, and the use of disease-modifying antirheumatic drugs (DMARDs) in a multinational cross-sectional cohort of nonselected consecutive outpatients with RA (The Questionnaires in Standard Monitoring of Patients with Rheumatoid Arthritis Program, or QUEST-RA) who were receiving regular clinical care.Methods
The study involved a clinical assessment by a rheumatologist and a self-report questionnaire by patients. The clinical assessment included a review of clinical features of RA and exposure to DMARDs over the course of RA. Comorbidities were recorded; CV morbidity included myocardial infarction, angina, coronary disease, coronary bypass surgery, and stroke. Traditional risk factors recorded were hypertension, hyperlipidemia, diabetes mellitus, smoking, physical inactivity, and body mass index. Unadjusted and adjusted hazard ratios (HRs) (95% confidence interval [CI]) for CV morbidity were calculated using Cox proportional hazard regression models.Results
Between January 2005 and October 2006, the QUEST-RA project included 4,363 patients from 48 sites in 15 countries; 78% were female, more than 90% were Caucasian, and the mean age was 57 years. The prevalence for lifetime CV events in the entire sample was 3.2% for myocardial infarction, 1.9% for stroke, and 9.3% for any CV event. The prevalence for CV risk factors was 32% for hypertension, 14% for hyperlipidemia, 8% for diabetes, 43% for ever-smoking, 73% for physical inactivity, and 18% for obesity. Traditional risk factors except obesity and physical inactivity were significantly associated with CV morbidity. There was an association between any CV event and age and male gender and between extra-articular disease and myocardial infarction. Prolonged exposure to methotrexate (HR 0.85; 95% CI 0.81 to 0.89), leflunomide (HR 0.59; 95% CI 0.43 to 0.79), sulfasalazine (HR 0.92; 95% CI 0.87 to 0.98), glucocorticoids (HR 0.95; 95% CI 0.92 to 0.98), and biologic agents (HR 0.42; 95% CI 0.21 to 0.81; P < 0.05) was associated with a reduction of the risk of CV morbidity; analyses were adjusted for traditional risk factors and countries.Conclusion
In conclusion, prolonged use of treatments such as methotrexate, sulfasalazine, leflunomide, glucocorticoids, and tumor necrosis factor-alpha blockers appears to be associated with a reduced risk of CV disease. In addition to traditional risk factors, extra-articular disease was associated with the occurrence of myocardial infarction in patients with RA. 相似文献935.
936.
At the authors' facility, housing arrangements for Xenopus laevis were cumbersome and labor-intensive, requiring technicians to wash frog tanks by hand several times a week. The authors describe an alternative housing solution they implemented by modifying a rack system that was originally used to maintain zebrafish. The rack's self-contained water circulation and filtration system saved technicians time and labor, and a commercial chiller attached to the mechanism efficiently controlled frogs' environmental temperature. 相似文献
937.
938.
Long-distance bird migration is fueled by energy gathered at stopover sites along the migration route. The refueling rate
at stopover sites is a determinant of time spent at stopovers and impacts the overall speed of migration. Refueling rate during
spring migration may influence the fitness of individuals via changes in the probability of successful migration and reproduction
during the subsequent breeding season. We evaluated four plasma lipid metabolites (triglycerides, phospholipids, β-OH-butyrate,
and glycerol) as measures of refueling rate in free-living semipalmated sandpipers (Calidris pusilla) captured at non-breeding areas. We described the spatial and temporal variation in metabolite concentrations among one winter
site in the Dominican Republic and four stopover sites in the South Atlantic and Mid-Atlantic Coastal Plain regions of North
America. Triglycerides and β-OH-butyrate clearly identified spatial variation in refueling rate and stopover habitat quality.
Metabolite profiles indicated that birds had higher refueling rates at one site in the Mid-Atlantic Coastal Plain than at
three sites on the South Atlantic Coastal Plain and one site in the Dominican Republic. Temporal variation in lipid metabolites
during the migration season suggested that male semipalmated sandpipers gained more weight at stopovers on the South Atlantic
Coastal Plain than did females, evidence of differential migration strategies for the sexes. Plasma lipid metabolites provide
information on migration physiology that may help determine stopover habitat quality and reveal how migratory populations
use stopover sites to refuel and successfully complete long-distance migrations. 相似文献
939.
González-Ittig RE Salazar-Bravo J Polop JJ Gardenal CN 《Molecular ecology resources》2008,8(6):1466-1468
The rodent Oligoryzomys longicaudatus or long-tailed pygmy rice rat is the reservoir of the aetiological agent of the hantavirus pulmonary syndrome in southern Argentina and Chile. We characterize 11 polymorphic microsatellite loci which would be useful for studies on microgeographical population structure in the species. Amplification of these loci in 42 individuals from four natural populations revealed four to 21 alleles per locus, and values of observed heterozygosities ranging from 0.371 to 0.896. Cross-species amplifications showed that some of the primers designed may be useful for other species of the genus Oligoryzomys. 相似文献
940.
Bonilla CA Crossa A Jave HO Mitnick CD Jamanca RB Herrera C Asencios L Mendoza A Bayona J Zignol M Jaramillo E 《PloS one》2008,3(8):e2957