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51.
Yang Yang Hart Stephen C. McCorkle Emma P. Stacy Erin M. Barnes Morgan E. Hunsaker Carolyn T. Johnson Dale W. Berhe Asmeret Asefaw 《Ecosystems》2021,24(8):1853-1874
Ecosystems - Understanding the transport of dissolved organic carbon (DOC) and nitrogen (N) as water flows through headwater basins is important for predicting downstream water quality. With... 相似文献
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Erin Loeding Jeanette Thomas Dave Bernier Rachel Santymire 《Journal of applied animal welfare science : JAAWS》2013,16(3):220-246
Introductions of sable antelope (Hippotragus niger) can be difficult due to the potential ensuing aggression compounded by their large horns. The goal was to use hormonal assays and behavioral analyses to evaluate the success of an introduction of 2 adult females at Lincoln Park Zoo. The objectives were to (a) document behavioral and hormonal changes in 2 female sable antelope during the introduction, (b) compare fecal glucocorticoid metabolites (FGM) in each individual during the introduction stages, (c) measure fecal androgen metabolites (FAM) during introduction and compare with dominance rank and observed aggression, and (d) monitor estrous cycle synchronization. Results demonstrate that FGM were higher before than during and after the introduction. Behavioral observations indicated limited aggression between females, although the keeper survey results revealed that the new female was more dominant and had higher mean FGM and FAM than the resident. Both sable antelope were reproductively active throughout the year. Results indicate that fecal hormone analysis can provide zoo management with valuable information to minimize the risk of aggression, injury, and stress during introductions of nonhuman animals. 相似文献
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Seth J. Schwartz Erin Phelps Jacqueline V. Lerner Shi Huang C. Hendricks Brown Selva Lewin-Bizan 《应用发育科学》2013,17(4):197-211
The present study was designed to examine the association of positive youth development with the likelihood of tobacco, alcohol, marijuana, hard drug, and sex initiation between 5th and 10th grades. A national, largely middle-class sample of 5,305 adolescents, participating in a longitudinal study funded by the National 4-H Council (although not all participants were enrolled in 4-H or other after-school programs), completed measures of positive youth development (PYD) constructs and of tobacco, alcohol, marijuana, and hard drug use once per year between 5th and 10th grades. At the 9th and 10th grade assessments, adolescents were asked whether they had initiated sexual intercourse and, if so, at what age they had first engaged in intercourse. Although the present sample was somewhat lower risk compared to national averages, survival analysis models indicated that PYD was significantly and negatively associated with the initiation hazards for tobacco use, marijuana use, and sex initiation for girls only, and with hard drug use for both genders. PYD was also positively associated with the odds of condom use across genders. Results are discussed with regard to PYD as a preventive process. 相似文献
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David A Martin Melvin Churchill Luis Felipe Flores-Suarez Mario H Cardiel Daniel Wallace Richard Martin Kristine Phillips Jeffrey L Kaine Hua Dong David Salinger Erin Stevens Chris B Russell James B Chung 《Arthritis research & therapy》2013,15(5):R164
Introduction
The aim of this study was to evaluate the safety, pharmacokinetics, and clinical response of brodalumab (AMG 827), a human, anti-IL-17 receptor A (IL-17RA) monoclonal antibody in subjects with moderate-to-severe rheumatoid arthritis (RA).Methods
This phase Ib, randomized, placebo-controlled, double-blind multiple ascending dose study enrolled subjects with moderate to severe RA (≥6/66 swollen and ≥8/68 tender joints). Subjects were randomized 3:1 to receive brodalumab (50 mg, 140 mg, or 210 mg subcutaneously every two weeks for 6 doses per group; or 420 mg or 700 mg intravenously every 4 weeks for two doses per group) or placebo. Endpoints included incidence of adverse events (AEs) and pharmacokinetics. Exploratory endpoints included pharmacodynamics, and improvements in RA clinical metrics.Results
Forty subjects were randomized to investigational product; one subject discontinued due to worsening of RA (placebo). The study was not designed to assess efficacy. AEs were reported by 70% (7/10) of placebo subjects and 77% (22/30) of brodalumab subjects. Three serious AEs were reported in two subjects; there were no opportunistic infections. Brodalumab treatment resulted in inhibition of IL-17 receptor signaling and receptor occupancy on circulating leukocytes. No treatment effects were observed with individual measures of RA disease activity. On day 85 (week 13) 37% (11/30) of brodalumab subjects and 22% (2/9) of placebo subjects achieved ACR20; 7% (2/30) brodalumab subjects and 11% (1/9) of placebo subjects achieved ACR50; and 0% (0/30) brodalumab subjects and 0% (0/9) of placebo subjects achieved ACR70.Conclusions
Multiple dose administration of brodalumab was tolerated in subjects with active RA. There was no evidence of a clinical response to brodalumab in subjects with RA.Trial registration
ClinicalTrials.gov, NCT00771030相似文献56.
Erin M. Leonard Chris M. Wood 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2013,158(1):10-21
We investigated the bioaccumulation and acute toxicity (48 h or 96 h) of Ni in four freshwater invertebrate species in two waters with hardness of 40 (soft water) and 140 mg L− 1 as CaCO3 (hard water). Sensitivity order (most to least) was Lymnaea stagnalis > Daphnia pulex > Lumbriculus variegatus > Chironomus riparius. In all cases water hardness was protective against acute Ni toxicity with LC50 values 3–3.5 × higher in the hard water vs. soft water. In addition, higher water hardness significantly reduced Ni bioaccumulation in these organisms suggesting that competition by Ca and Mg for uptake at the biotic ligand may contribute to higher metal resistance. CBR50 values (Critical Body Residues) were less dependent on water chemistry (i.e. more consistent) than LC50 values within and across species by ~ 2 fold. These data support one of the main advantages of the Tissue Residue Approach (TRA) where tissue concentrations are generally less variable than exposure concentrations with respect to toxicity. Whole body Ni bioaccumulation followed Michaelis–Menten kinetics in all organisms, with greater hardness tending to decrease Bmax with no consistent effect on Kd. Across species, acute Ni LC50 values tended to increase with both Kd and Bmax values — i.e. more sensitive species exhibited higher binding affinity and lower binding capacity for Ni, but there was no correlation with body size. With respect to biotic ligand modeling, log KNiBL values derived from Ni bioaccumulation correlated well with log KNiBL values derived from toxicity testing. Both whole body Na and Mg levels were disturbed, suggesting that disruption of ionoregulatory homeostasis is a mechanism of acute Ni toxicity. In L. stagnalis, Na depletion was a more sensitive endpoint than mortality, however, the opposite was true for the other organisms. This is the first study to show the relationship between Na and Ni. 相似文献
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Breeding is limited by energetic or environmental constraints and long-lived species sometimes skip breeding opportunities. Environmental conditions may vary considerably across the geographic and elevational range of a species and species that can respond through variation in life history strategies are likely to maintain populations at the extremes of their ranges. The decision to skip breeding enables animals to adjust life history to circumstances, and plasticity in behavior allows implementation of adjustments. Elevational patterns suggest that breeding may be limited physiologically at high elevations (e.g., greater probability of skipped breeding; resources and environmental conditions more variable) in contrast to low elevations (probability of skipping breeding lower; resources and environmental conditions more predictable). We estimated the probabilities of survival and skipped breeding in a high-elevation population of common toads and compared estimates to existing data for common toads at low elevations, and to another toad species inhabiting a similar high elevation environment. Female common toads at high elevations tend to have high probabilities of skipping breeding and survival relative to data for common toads at low elevations, and appear to use a similar strategy of skipping breeding in response to similar environmental constraints as other toads at high elevations. We provide evidence of variability in this aspect of life history for common toads. Understanding variation in life history within widely distributed species is critical. Knowing that certain life history strategies are employed on a continuum informs conservation efforts, especially as impacts of climate change are likely to be different depending on elevation. 相似文献
59.
Background and Objectives
Following the 2010 earthquake in Haiti, infant and young child feeding was identified as a priority nutrition intervention. A new approach to support breastfeeding mothers and distribute ready-to-use infant formula (RUIF) to infants unable to breastfeed was established. The objective of the evaluation was to assess the implementation of infant feeding programs using RUIF in displaced persons camps in Port-au-Prince, Haiti during the humanitarian response.Methods
A retrospective record review was conducted from April–July, 2010 to obtain data on infants receiving RUIF in 30 baby tents. A standardized data collection form was created based on data collected across baby tents and included: basic demographics, admission criteria, primary caretaker, feeding practices, and admission and follow-up anthropometrics.Main Findings
Orphans and abandoned infants were the most frequent enrollees (41%) in the program. While the program targeted these groups, it is unlikely that this is a true reflection of population demographics. Despite programmatic guidance, admission criteria were not consistently applied across programs. Thirty-four percent of infants were undernourished (weight for age Z score <−2) at the time of admission. Defaulting accounted for 50% of all program exits and there was no follow-up of these children. Low data quality was a significant barrier.Conclusions
The design, implementation and magnitude of the ‘baby tents’ using RUIF was novel in response to infant and young child feeding (IYCF) in emergencies and presented multiple challenges that should not be overlooked, including adherence to protocols and the adaption of emergency programs to existing programs. The implementation of IYCF programs should be closely monitored to ensure that they achieve the objectives set by the humanitarian community and national government. IYCF is an often overlooked component of emergency preparedness; however to improve response, generic protocols and pre-emergency training and preparedness should be established for humanitarian agencies. 相似文献60.
David N. Juurlink Colin R. Dormuth Anjie Huang Chelsea Hellings J. Michael Paterson Colette Raymond Anita Kozyrskyj Yola Moride Erin M. Macdonald Muhammad M. Mamdani 《PloS one》2013,8(12)