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991.
Male mate choice via cuticular hydrocarbon pheromones drives reproductive isolation between Drosophila species
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![点击此处可从《Evolution; international journal of organic evolution》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Michael P. Shahandeh Alison Pischedda Thomas L. Turner 《Evolution; international journal of organic evolution》2018,72(1):123-135
Mate discrimination is a key mechanism restricting gene flow between species. While studied extensively with respect to female mate choice, mechanisms of male mate choice between species are far less studied. Thus, we have little knowledge of the relative frequency, importance, or overall contribution of male mate discrimination to reproductive isolation. In the present study, we estimated the relative contributions of male and female choice to reproductive isolation between Drosophila simulans and D. sechellia, and show that male mate discrimination accounts for the majority of the current isolation between these species. We further demonstrate that males discriminate based on female cuticular hydrocarbon pheromones, and collect evidence supporting the hypothesis that male mate discrimination may alleviate the costs associated with heterospecific courtship and mating. Our findings highlight the potentially significant contribution of male mate choice to the formation of reproductive isolating barriers, and thus the speciation process. 相似文献
992.
993.
Assessing global range expansion in a cryptic species complex: insights from the red seaweed genus Asparagopsis (Florideophyceae)
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![点击此处可从《Journal of phycology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Marianela Zanolla María Altamirano Raquel Carmona Julio De la Rosa Virginia Souza‐Egipsy Alison Sherwood Konstantinos Tsiamis Ana Márcia Barbosa Antonio Román Muñoz Nikos Andreakis 《Journal of phycology》2018,54(1):12-24
The mitochondrial genetic diversity, distribution and invasive potential of multiple cryptic operational taxonomic units (OTUs) of the red invasive seaweed Asparagopsis were assessed by studying introduced Mediterranean and Hawaiian populations. Invasive behavior of each Asparagopsis OTU was inferred from phylogeographic reconstructions, past historical demographic dynamics, recent range expansion assessments and future distributional predictions obtained from demographic models. Genealogical networks resolved Asparagopsis gametophytes and tetrasporophytes into four A. taxiformis and one A. armata cryptic OTUs. Falkenbergia isolates of A. taxiformis L3 were recovered for the first time in the western Mediterranean Sea and represent a new introduction for this area. Neutrality statistics supported past range expansion for A. taxiformis L1 and L2 in Hawaii. On the other hand, extreme geographic expansion and an increase in effective population size were found only for A. taxiformis L2 in the western Mediterranean Sea. Distribution models predicted shifts of the climatically suitable areas and population expansion for A. armata L1 and A. taxiformis L1 and L2. Our integrated study confirms a high invasive risk for A. taxiformis L1 and L2 in temperate and tropical areas. Despite the differences in predictions among modelling approaches, a number of regions were identified as zones with high invasion risk for A. taxiformis L2. Since range shifts are likely climate‐driven phenomena, future invasive behavior cannot be excluded for the rest of the lineages. 相似文献
994.
Antisense Therapy for a Common Corneal Dystrophy Ameliorates TCF4 Repeat Expansion-Mediated Toxicity
Christina Zarouchlioti Beatriz Sanchez-Pintado Nathaniel J. Hafford Tear Pontus Klein Petra Liskova Kalyan Dulla Ma’ayan Semo Anthony A. Vugler Kirithika Muthusamy Lubica Dudakova Hannah J. Levis Pavlina Skalicka Pirro Hysi Michael E. Cheetham Stephen J. Tuft Peter Adamson Alison J. Hardcastle Alice E. Davidson 《American journal of human genetics》2018,102(4):528-539
995.
Enrichment of high affinity subclasses and glycoforms from serum‐derived IgG using FcγRs as affinity ligands
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![点击此处可从《Biotechnology and bioengineering》网站下载免费的PDF全文](/ch/ext_images/free.gif)
996.
Anil?K.?PokhariaEmail author B.?R.?Mani Michael?Spate Alison?Betts Alka?Srivastava 《Vegetation History and Archaeobotany》2018,27(3):477-491
Here we report the results of an archaeobotanical study carried out on Ceramic Neolithic (2700–2000 bc) and Kushan period (ad 100–300) deposits at Kanispur, Kashmir, northern India. Botanical evidence from the Ceramic Neolithic phase reflects a nascent agriculture based on cold-tolerant crops (barley, wheats, lentil, field pea and grass pea) related to farming patterns of adjacent cultures and possibly evidence for the earliest cultivation in the valley. The Kushan period is characterized by a double-cropping pattern, suggesting a change in agricultural practices associated with a population recovery following a post-Neolithic decline. Finds of Juglans regia, and Prunus cf. amygdalus shells in ceramic Neolithic levels, and Vitis cf. vinifera, Emblica officinalis and Ziziphus cf. nummularia in addition to J. regia, and P. cf. amygdalus during Kushan times suggest that horticulture and foraging played an important role in the diet of the occupants. The present dataset provides new absolute dates for the subsistence economy of the Ceramic Neolithic population in the Kashmir Valley. We also present the oldest directly dated wheat and barley in Kashmir. 相似文献
997.
Adrian M. Hewitt Alison A. Kock Anthony J. Booth Charles L. Griffiths 《Environmental Biology of Fishes》2018,101(1):39-54
A long-term sightings and photographic identification (photo-ID) database documented the inter-annual and monthly trends in white shark (Carcharodon carcharias) sightings, sex ratios and life-history stages at Seal Island, False Bay, South Africa, over the period 2004–2012. A total of 1105 sightings were recorded during 171 scientific surveys incorporating 577 h of observation (annual mean 64.10 h, range 23.71–178.69 h). The mean annual sighting rate was 1.87 (range 0.90–3.19) sharks per hour and sighting rates declined over the nine-year study period. It is unknown whether the decline resulted from an actual population decline, or was due to changes in shark distribution or environmental conditions, but it highlights the need for ongoing monitoring at this site. The overall sex ratio was 1.0: 1.0: 2.3 for male: female: unsexed sharks, respectively. Of the 1105 sightings, 39% (n = 433) were photo-ID’d, representing 303 individual sharks (112: 111: 80, male: female: unsexed) and 130 resightings. Of the 303 photo-ID’d sharks, 71% were sighted in a single year only, indicative of transient behaviour. Of the 29% of sharks that were resighted in more than one year, 65% were resighted in the following year, indicating site fidelity to Seal Island, whereas 35% skipped one or more years between encounters, indicative of a temporary absence. The majority (60%) of the photo-ID’d sharks were immature, 32% were subadult and only 8% were mature. No young-of-the-year sharks and few adults were recorded, indicating that Seal Island is not an adult aggregation site, nor a pupping or nursery area, but rather is best described as a seasonal feeding ground. Large females were rarely resighted again after they approached length-at-maturity (≥450 cm TL), whereas some adult males were recorded consistently across years. The emigration of subadult female sharks approaching maturity from Seal Island, combined with the small number of mature sharks of both sexes reported from any South African location, indicate that adult aggregation sites, and thus areas of reproductive importance, still remain unknown. 相似文献
998.
Kristen Steele Sally Chadwick Alison Debney Matthew Gollock 《Wetlands Ecology and Management》2018,26(6):1181-1188
The European eel (Anguilla anguilla, L.) was historically widely distributed throughout the United Kingdom, in coastal waters, lakes, rivers and wetlands. Recruitment has declined in recent decades and the species is now listed as ‘Critically Endangered’ on the International Union for Conservation of Nature and Natural Resources (IUCN) Red List. Management of suitable wetland habitats may contribute to species recovery; however, little is known about the stocks in these areas. In this study, yellow (adult stage?>?300 mm) eels were sampled in ditches in five marshes bordering the Thames Estuary in England, UK. Ecological variables, including ditch characteristics, invertebrate abundance and water quality parameters were measured. Habitat features were also observed and recorded, including access, land use and water management regimes. Eels were found in all marshes, but at varying catch-per-unit-effort (CPUE). There were no significant correlations between CPUE and the ecological variables, except ditch width. However, a significant difference in CPUE was found between two of the marshes, which may be explained by variations in local habitat management. Mean lengths showed a high proportion of females and mean body condition of four of the marshes was also found to be greater than in three rivers in the same region. These findings suggest that the marshes are potentially favourable eel habitats and that factors influencing habitat quality, such as land use and water management, may affect eel abundance, production of females and body condition. Effective management of such wetlands may therefore contribute to the conservation of European eel. 相似文献
999.
Infrared absorbance spectroscopy of aqueous proteins: Comparison of transmission and ATR data collection and analysis for secondary structure fitting
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![点击此处可从《Chirality》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Marco Pinto Corujo Meropi Sklepari Dale L. Ang Mark Millichip Andrew Reason Sophia C. Goodchild Paul Wormell Don Praveen Amarasinghe Viv Lindo Nikola P. Chmel Alison Rodger 《Chirality》2018,30(8):957-965
Attenuated total reflectance (ATR) infrared absorbance spectroscopy of proteins in aqueous solution is much easier to perform than transmission spectroscopy, where short path‐length cells need to be assembled reproducibly. However, the shape of the resulting ATR infrared spectrum varies with the refractive index of the sample and the instrument configuration. Refractive index in turn depends on the absorbance of the sample. In this work, it is shown that a room temperature triglycine sulfate detector and a ZnSe ATR unit can be used to collect reproducible spectra of proteins. A simple method for transforming the protein ATR spectrum into the shape of the transmission spectrum is also given, which proceeds by approximating a Kramers‐Krönig–determined refractive index of water as a sum of four linear components across the amide I and II regions. The light intensity at the crystal surface (with 45° incidence) and its rate of decay away from the surface is determined as a function of the wave number–dependent refractive index as well as the decay of the evanescent wave from the surface. The result is a single correction factor at each wave number. The spectra were normalized to a maximum of 1 between 1600 cm?1 and 1700 cm?1 and a self‐organizing map secondary structure fitting algorithm, SOMSpec, applied using the BioTools reference set. The resulting secondary structure estimates are encouraging for the future of ATR spectroscopy for biopharmaceutical characterization and quality control applications. 相似文献
1000.
Marguerite A. Renouf Mark Poggio Alison Collier Nicole Price Bernard L. Schroeder Peter G. Allsopp 《The International Journal of Life Cycle Assessment》2018,23(11):2150-2164