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991.
Based on the diagnostic morphological characters of the Arundo taxa, and after both field and herbarium observation, three species (A. micrantha, A. plinii and A. donax) were found along the eastern Adriatic coast. Altogether, 50 phytocoenological relevés from Arundo stands were collected in Croatia, Montenegro and Albania between 2010 and 2013. Three associations with a predominance of Arundo species were determined: Arundinetum plinianae, Arundinetum micranthae and Arundini donacis–Convolvuletum sepium. Among them, Arundinetum micranthae is described and proposed as a new association, belonging to the Artemisietea vulgaris class. It occurs frequently along the coastal belt between the cities of Split and Dubrovnik in South Croatia. The syntaxonomy of the associations is discussed and comparison with similar communities from Italy is made. The vegetation and floristic structure of the associations is discussed as a potential basis for biodiversity conservation programmes and for evaluating the state of these ecosystems in the future. 相似文献
992.
993.
J. Malá P. Máchová H. Cvrčková M. Karady O. Novák J. Mikulík J. Dostál M. Strnad K. Doležal 《Biologia Plantarum》2013,57(1):174-178
We have compared the influence of two aromatic cytokinin derivatives, N 6-benzyladenine (BA) and meta-topolin (mT), on the in vitro multiplication and senescence of wych elm (Ulmus glabra Huds.). After 3 months of cultivation, the micropropagation rate was higher (approx. six times more shoots developed) on Murashige and Skoog (MS) medium supplemented with mT than on MS supplemented with BA. Quantification of 50 endogenous cytokinins, using a recently developed UPLC-ESI(+)-MS/MS method, showed significant differences in the cytokinin metabolites (especially different glucosides) in explants cultivated on media supplemented with BA or mT. Differences in efficiency of photosystem II was also detected. 相似文献
994.
995.
Maria Sporbert Petr Keil Gunnar Seidler Helge Bruelheide Ute Jandt Svetlana Aćić Idoia Biurrun Juan Antonio Campos Andraž Čarni Milan Chytrý Renata Ćušterevska Jürgen Dengler Valentin Golub Florian Jansen Anna Kuzemko Jonathan Lenoir Corrado Marcenò Jesper Erenskjold Moeslund Aaron Pérez-Haase Solvita Rūsiņa Urban Šilc Ioannis Tsiripidris Vigdis Vandvik Kiril Vasilev Risto Virtanen Erik Welk 《Journal of Biogeography》2020,47(10):2210-2222
996.
Peder Olesen Larsen Elžbieta Wieczorkowska 《Biochimica et Biophysica Acta (BBA)/General Subjects》1978,542(2):253-262
3-(3-Carboxyphenyl)-DL-[2-14C]alanine has been incorporated into four species of iris. In all species extensive metabolization takes place. In Iris × hollandica, in which both the alanine derivative and 3′-carboxyphenylglycine occur, the products identified are the glycine derivative, 3′-carboxyphenylacetate acid, 3′-carboxymandelic acid, and 3′-carboxyphenylglyoxylic acid. In I. sanguinea, in which the alanine and glycine derivatives also occur, the products identified are the glycine and acetic acid derivatives but the major product is 3-(3-hydroxymethylphenyl)alanine, a naturally occurring amino acid in this species. In I. tectorum, in which only the carboxy-substituted alanine derivative occurs, the products identified are the acetic acid and glyoxylic acid derivatives. In I. pallida, not containing any of the meta-substituted amino acids, the products identified are again the acetic acid and glyoxylic acid derivatives. The results have been further substantiated by incorporation of labelled 3′-carboxyphenylacetic acid and 3′-carboxymandelic acid into I. × hollandica and I. sanguinea.The results demonstrate three different metabolic patterns for the alanine derivative and confirm previous results on the pathway from the alanine to the glycine derivative. Furthermore, the results may be of significance for the elucidation of the catabolism of phenylalanine. 相似文献
997.
Marija Miličić Snežana Popov Ante Vujić Bojana Ivošević Pedro Cardoso 《Ecological Entomology》2020,45(2):232-242
1. Dark diversity represents the set of species that can potentially inhabit a given area under particular ecological conditions, but are currently ‘missing’ from a site. This concept allows characterisation of the mechanisms determining why species are sometimes absent from an area that seems ecologically suitable for them. 2. The aim of this study was to determine the dark diversity of hoverflies in south-eastern Europe and to discuss the role of different functional traits that might increase the likelihood of species contributing to dark diversity. Based on expert opinion, the Syrph the Net database and known occurrences of species, the study estimated species pools, and observed and dark diversities within each of 11 defined vegetation types for 564 hoverfly species registered in south-eastern Europe. To detect the most important functional traits contributing to species being in dark diversity across different vegetation types, a random forest algorithm and respective statistics for variable importance were used. 3. The highest dark diversity was found for southwest Balkan sub-Mediterranean mixed oak forest type, whereas the lowest was in Mediterranean mixed forest type. Three larval feeding modes (saproxylic, and phytophagous on bulbs or roots) were found to be most important for determining the probability of a species contributing to hoverfly dark diversity, based on univariate correlations and random forest analysis. 4. This study shows that studying dark diversity might provide important insights into what drives community assembly in south-eastern European hoverflies, especially its missing components, and contributes to more precise conservation prioritisation of both hoverfly species and their habitats. 相似文献
998.
Ferdinand Kryž 《Plant Systematics and Evolution》1910,60(6):209-218
Ohne Zusammenfassung 相似文献
999.
Sky,sea, and forest islands: Diversification in the African leaf‐folding frog Afrixalus paradorsalis (Anura: Hyperoliidae) of the Lower Guineo‐Congolian rain forest 下载免费PDF全文
1000.
Slavomír Bystrický Eva Machova´ Peter Bartek Nadežda Kolarova Grigorij Kogan 《Glycoconjugate journal》2000,17(10):677-680
The possibility of using 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) for activation of saccharide hydroxyl groups (instead of hazardous cyanogen bromide) is examined with cell-surface mannans of the yeasts Candida albicans
Candida tropicalis,Candida lambicaand galactoglucoxylomannan of Cryptococcus laurentii.Direct conjugation with human serum albumin yielded soluble products with increased molecular size in comparison with the original polysaccharides. Immunodiffusion experiments revealed that conjugation did not affect the immunospecificity of the antigen epitope. 相似文献