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21.
Genome sequence of Babesia bovis and comparative analysis of apicomplexan hemoprotozoa 总被引:1,自引:0,他引:1
Brayton KA Lau AO Herndon DR Hannick L Kappmeyer LS Berens SJ Bidwell SL Brown WC Crabtree J Fadrosh D Feldblum T Forberger HA Haas BJ Howell JM Khouri H Koo H Mann DJ Norimine J Paulsen IT Radune D Ren Q Smith RK Suarez CE White O Wortman JR Knowles DP McElwain TF Nene VM 《PLoS pathogens》2007,3(10):1401-1413
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23.
FALINE M. DRUMMOND Kevin A. Parker Tim G. Lovegrove Doug P. Armstrong 《The Journal of wildlife management》2019,83(8):1744-1752
Detailed data on juvenile survival are rare in the literature. Although many studies estimate recruitment, if you cannot distinguish between permanent dispersal and mortality, the management implications for a population may be unclear. We estimated juvenile survival in a reintroduced North Island robin (Petroica longipes) population in a protected sanctuary surrounded by an unprotected landscape where the species is extirpated. The population has had marginal population growth due to poor recruitment so we modeled 3 types of data (resighting of fledglings, radio-telemetry of independent juveniles, resighting of adults) in an integrated framework to determine the life stages where high mortality was occurring, and to distinguish mortality from dispersal. Approximately 16% of birds that fledged (n = 109) were present at the start of the next breeding season, consistent with recruitment rates from previous years. Low survival in the first 6 weeks after fledging was the primary cause of poor recruitment. Only 50% survived to independence (4 weeks after fledging), and 18% survived to the end of the radio-tracking period (14 weeks), after which juvenile survival matched adult survival. No dispersal from the sanctuary occurred during the radio-tracking period. Juveniles moved between adjacent forest fragments within the sanctuary, but did not leave the sanctuary. This information, which demonstrates the importance of distinguishing between natal mortality and dispersal, is important for ongoing management of the site and selection of future reintroduction sites for this species. © 2019 The Wildlife Society. 相似文献
24.
Lieberman Joshua A. Fiorito Joseph Ichikawa Doug Fang Ferric C. Rakita Robert M. Bourassa Lori 《Mycopathologia》2019,184(5):671-676
Mycopathologia - Medicopsis species are rare fungal pathogens that frequently resist common antifungal therapies and are difficult to identify morphologically as conidia are produced in pycnidia, a... 相似文献
25.
Brittany L. Wagler Rachel A. Smiley Alyson B. Courtemanch Gregory Anderson Daryl Lutz Doug McWhirter Doug Brimeyer Patrick Hnilicka Cody P. Massing David W. German Thomas R. Stephenson Kevin L. Monteith 《The Journal of wildlife management》2022,86(3):e22181
Wildlife capture, and the data collection associated with it, has led to major advancements in ecology that are integral to decision making pertaining to wildlife conservation. Capturing wildlife, however, can cause lethal and non-lethal risks to animals. Understanding the factors that contribute to the level of risk involved in wildlife capture is therefore important for the development and implementation of the safest and most effective methodologies. We used data from 736 animal captures of 389 individuals for 2 subspecies of female bighorn sheep (Rocky Mountain bighorn [Ovis canadensis canadensis], Sierra Nevada bighorn sheep [O. c. sierrae]) in Wyoming and California, USA, in 2002–2020 to evaluate the degree and extent of time that capture via helicopter net-gunning affects survival. We compared pre- and post-capture survival during a 10-week window centered on a capture event, and post-capture survival between captured animals and animals that were monitored but not captured during the 10-week window. Additionally, we evaluated the effects of handling techniques (number of times captured, season of capture event, handling time, chase time, and body temp) and biological factors (age and nutritional condition) on probability of capture mortality. Mean daily survival was 0.9992 during a 5-week pre-capture window, dropped to 0.9864 on the day of capture, and rebounded within 3 days of capture to pre-capture levels and that of sheep that were not captured. Overall, direct mortality resulting from capture was 1.36%, with 0.54% mortality occurring within the 3 days following a capture event for an overall 1.90% capture-related mortality. The only handling and biological metrics that influenced the probability of capture mortality were rectal temperature and nutritional condition; high initial rectal temperatures and poor body condition were associated with increased risk of mortality in the days following capture. Overall, helicopter net-gunning imposed low and short-term risk to survival of female bighorn sheep. To reduce bias in survival estimates, we recommend using a 3-day censorship window for post-capture mortalities as opposed to the common practice of a 2–5-week censor window. Helicopter net-gunning, including annual or seasonal recaptures, remains an effective and comparatively safe technique for capture and associated data collection of bighorn sheep. 相似文献
26.
The objective of this study was to determine the genomic changes that underlie coevolution between Escherichia coli B and bacteriophage T3 when grown together in a laboratory microcosm. We also sought to evaluate the repeatability of their evolution by studying replicate coevolution experiments inoculated with the same ancestral strains. We performed the coevolution experiments by growing Escherichia coli B and the lytic bacteriophage T3 in seven parallel continuous culture devices (chemostats) for 30 days. In each of the chemostats, we observed three rounds of coevolution. First, bacteria evolved resistance to infection by the ancestral phage. Then, a new phage type evolved that was capable of infecting the resistant bacteria as well as the sensitive bacterial ancestor. Finally, we observed second-order resistant bacteria evolve that were resistant to infection by both phage types. To identify the genetic changes underlying coevolution, we isolated first- and second-order resistant bacteria as well as a host-range mutant phage from each chemostat and sequenced their genomes. We found that first-order resistant bacteria consistently evolved resistance to phage via mutations in the gene, waaG, which codes for a glucosyltransferase required for assembly of the bacterial lipopolysaccharide (LPS). Phage also showed repeatable evolution, with each chemostat producing host-range mutant phage with mutations in the phage tail fiber gene T3p48 which binds to the bacterial LPS during adsorption. Two second-order resistant bacteria evolved via mutations in different genes involved in the phage interaction. Although a wide range of mutations occurred in the bacterial waaG gene, mutations in the phage tail fiber were restricted to a single codon, and several phage showed convergent evolution at the nucleotide level. These results are consistent with previous studies in other systems that have documented repeatable evolution in bacteria at the level of pathways or genes and repeatable evolution in viruses at the nucleotide level. Our data are also consistent with the expectation that adaptation via loss-of-function mutations is less constrained than adaptation via gain-of-function mutations. 相似文献
27.
The Open Microscopy Environment (OME) Data Model and XML file: open tools for informatics and quantitative analysis in biological imaging 总被引:2,自引:0,他引:2
Goldberg IG Allan C Burel JM Creager D Falconi A Hochheiser H Johnston J Mellen J Sorger PK Swedlow JR 《Genome biology》2005,6(5):R47
The Open Microscopy Environment (OME) defines a data model and a software implementation to serve as an informatics framework for imaging in biological microscopy experiments, including representation of acquisition parameters, annotations and image analysis results. OME is designed to support high-content cell-based screening as well as traditional image analysis applications. The OME Data Model, expressed in Extensible Markup Language (XML) and realized in a traditional database, is both extensible and self-describing, allowing it to meet emerging imaging and analysis needs. 相似文献
28.
Influences of salinity on the physiology and distribution of the Arctic coralline algae,Lithothamnion glaciale (Corallinales,Rhodophyta) 下载免费PDF全文
Kathryn M. Schoenrock Marion Bacquet Danni Pearce Brice R. Rea J. Edward Schofield James Lea Doug Mair Nicholas Kamenos 《Journal of phycology》2018,54(5):690-702
In Greenland, free‐living red coralline algae contribute to and dominate marine habitats along the coastline. Lithothamnion glaciale dominates coralline algae beds in many regions of the Arctic, but never in Godthåbsfjord, Greenland, where Clathromorphum sp. is dominant. To investigate environmental impacts on coralline algae distribution, calcification and primary productivity were measured in situ during summers of 2015 and 2016, and annual patterns of productivity in L. glaciale were monitored in laboratory‐based mesocosm experiments where temperature and salinity were manipulated to mimic high glacial melt. The results of field and cold‐room measurements indicate that both L. glaciale and Clathromorphum sp. had low calcification and photosynthetic rates during the Greenland summer (2015 and 2016), with maximum of 1.225 ± 0.17 or 0.002 ± 0.023 μmol CaCO 3 · g?1 · h?1 and ?0.007 ±0.003 or ?0.004 ± 0.001 mg O2 · L?1 · h?1 in each species respectively. Mesocosm experiments indicate L. glaciale is a seasonal responder; photosynthetic and calcification rates increase with annual light cycles. Furthermore, metabolic processes in L. glaciale were negatively influenced by low salinity; positive growth rates only occurred in marine treatments where individuals accumulated an average of 1.85 ± 1.73 mg · d?1 of biomass through summer. These results indicate high freshwater input to the Godthåbsfjord region may drive the low abundance of L . glaciale , and could decrease species distribution as climate change increases freshwater input to the Arctic marine system via enhanced ice sheet runoff and glacier calving. 相似文献
29.
Specialized acrobatic leaping has been recognized as a key adaptive trait tied to the origin and subsequent radiation of euprimates based on its observed frequency in extant primates and inferred frequency in extinct early euprimates. Hypothesized skeletal correlates include elongated tarsal elements, which would be expected to aid leaping by allowing for increased rates and durations of propulsive acceleration at takeoff. Alternatively, authors of a recent study argued that pronounced distal calcaneal elongation of euprimates (compared to other mammalian taxa) was related primarily to specialized pedal grasping. Testing for correlations between calcaneal elongation and leaping versus grasping is complicated by body size differences and associated allometric affects. We re-assess allometric constraints on, and the functional significance of, calcaneal elongation using phylogenetic comparative methods, and present an evolutionary hypothesis for the evolution of calcaneal elongation in primates using a Bayesian approach to ancestral state reconstruction (ASR). Results show that among all primates, logged ratios of distal calcaneal length to total calcaneal length are inversely correlated with logged body mass proxies derived from the area of the calcaneal facet for the cuboid. Results from phylogenetic ANOVA on residuals from this allometric line suggest that deviations are explained by degree of leaping specialization in prosimians, but not anthropoids. Results from ASR suggest that non-allometric increases in calcaneal elongation began in the primate stem lineage and continued independently in haplorhines and strepsirrhines. Anthropoid and lorisid lineages show stasis and decreasing elongation, respectively. Initial increases in calcaneal elongation in primate evolution may be related to either development of hallucal-grasping or a combination of grasping and more specialized leaping behaviors. As has been previously suggested, subsequent increases in calcaneal elongation are likely adaptations for more effective acrobatic leaping, highlighting the importance of this behavior in early euprimate evolution. 相似文献
30.
Steven T. Gardner Emily M. Bertucci Randall Sutton Andy Horcher Doug Aubrey Benjamin B. Parrott 《Molecular ecology resources》2023,23(1):131-144
Biological ageing is connected to life history variation across ecological scales and informs a basic understanding of age-related declines in organismal function. Altered DNA methylation dynamics are a conserved aspect of biological ageing and have recently been modelled to predict chronological age among vertebrate species. In addition to their utility in estimating individual age, differences between chronological and predicted ages arise due to acceleration or deceleration of epigenetic ageing, and these discrepancies are linked to disease risk and multiple life history traits. Although evidence suggests that patterns of DNA methylation can describe ageing in plants, predictions with epigenetic clocks have yet to be performed. Here, we resolve the DNA methylome across CpG, CHG, and CHH-methylation contexts in the loblolly pine tree (Pinus taeda) and construct epigenetic clocks capable of predicting ages in this species within 6% of its maximum lifespan. Although patterns of CHH-methylation showed little association with age, both CpG and CHG-methylation contexts were strongly associated with ageing, largely becoming hypomethylated with age. Among age-associated loci were those in close proximity to malate dehydrogenase, NADH dehydrogenase, and 18S and 26S ribosomal RNA genes. This study reports one of the first epigenetic clocks in plants and demonstrates the universality of age-associated DNA methylation dynamics which can inform conservation and management practices, as well as our ecological and evolutionary understanding of biological ageing in plants. 相似文献