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111.
Michael E. Dodd Jonathan Silvertown Mark W. Chase 《Evolution; international journal of organic evolution》1999,53(3):732-744
Angiosperm families differ greatly from one another in species richness (S). Previous studies have attributed significant components of this variation to the influence of pollination mode (biotic/abiotic) and growth form (herbaceous/woody) on speciation rate, but these results suffer difficulties of interpretation because all the studies ignored the phylogenetic relationships among families. We use a molecular phylogeny of the angiosperm families to reanalyse correlations between S and family-level traits and use reconstructions of trait evolution to interpret the results. We confirm that pollination mode and growth form are correlated with S and show that the majority of changes in pollination mode involved a change from biotic to abiotic pollination with an associated fall in speciation rate. The majority of growth form changes involved the evolution of herbaceousness from woodiness with a correlated rise in speciation rate. We test the hypothesis of Ricklefs and Renner (1994) that “evolutionary flexibility” rather than other trait changes triggered increased speciation rates in some families, but find little support for the hypothesis. 相似文献
112.
BERNHARD HAUSDORF 《Biological journal of the Linnean Society. Linnean Society of London》2001,74(3):387-395
The vitrinids, which represent a probably competitively inferior transitional stage between shelled snails and slugs, and their sister group, the limacoid slugs, are used to investigate a macroevolutionary effect of a microevolutionary process, competition between individuals resulting in ecological displacement of one clade by another, based on patterns in the present-day world. The activity period and the altitudinal distribution of the vitrinids has shifted - to the cold season or to higher altitudes, respectively - in those regions where their range overlaps with that of the limacoid slugs. The diversity of the vitrinids is lower in regions with limacoid slugs. These patterns can be ascribed to the ecological displacement or the exclusion of the vitrinids from some habitats by limacoid slugs. Two vitrinid clades which independently colonized regions without limacoid slugs show patterns attributable to ecological release. The ecological displacement or exclusion of the vitrinids by the slugs is probably due to competition for shelter. 相似文献
113.
The succession of 38 upper Llandovery–lower Wenlock chitinozoan taxa from graptolitic horizons in the Banwy River section (Powys, Wales) is described. Five new species are named: Bursachitina nestorae Conochitina leviscapulae Conochitina mathrafalensis Belonechitina cavei Belonechitina meifodensis . A further ten taxa are described under open nomenclature. Seven chitinozoan biozones are recognized in the Banwy River section, three of which ( Cingulochitina bouniensis Conochitina acuminata Salopochitina bella ) are new. The base of each biozone is correlated with the graptolite biostratigraphical scheme as follows: Angochitina longicollis Biozone — upper spiralis Biozone; Conochitina acuminata Biozone — lowermost lapworthi Biozone; Margachitina banwyensis Biozone — upper lapworthi Biozone; Margachitina margaritana Biozone — lowermost insectus Biozone; Cingulochitina bouniensis Biozone — upper murchisoni Biozone; Salopochitina bella Biozone — upper firmus Biozone. The succession of chitinozoan biozones in the Banwy River section is compared with that in other sections which have graptolite biostratigraphical control. This has highlighted the following: (1) the correlation of the base of the dolioliformis Biozone with the graptolite biozonation is imprecise; (2) E. dolioliformis is recorded only from levels after the first A. longicollis in Sweden (although this may reflect previously unrecognized synonymies); (3) the longicollis Biozone may be diachronous, its base correlating with levels low in the Telychian in Sweden, Norway and Estonia and with the upper Telychian spiralis Biozone in Wales and the Prague Basin; (4) data herein and from the Prague Basin indicate that the base of the margaritana Biozone correlates with a level low in the insectus Biozone. 相似文献
114.
LIDIA ITATI FERRARO ROBERT LÜCKING EMMANUËL SÉRUSIAUX 《Botanical journal of the Linnean Society. Linnean Society of London》2001,137(3):311-345
Seventeen new species of Gyalectidium have been discovered in various parts of the world, and those unexpected findings formed the starting point for a survey of the taxonomy and ecogeography of the genus. The following species are described as new in this paper: G. areolatum Ferraro & Lucking (Neotropics), G. atrosquamulatum Lucking & Kalb (Kenya), G . australe Lücking (Australia), G. conchiferum Lücking& Wirth (Chile), G. den-ticulatum Lücking (Costa Rica), G. fantasticum Ferraro & Lücking (Neotropics), G. flabellatum Sérus. (Australasia), G. fuscum Lücking & Sérus. (Africa and Papua New Guinea), G. gahavisukanum Sérus. (Papua New Guinea), G. kenyanum Lücking & Kalb (Kenya). G. laciniatum Lücking (Costa Rica), G. maracae Lücking (Neotropics), G. membranaceum Sérus. & Lücking (Canary Islands), G. minus Sérus (Canary Islands and southern Italy), G. novoguineense Sérus. (Australasia), G. puntilloi Sérus. (south-west Europe), and G. verruculosum Sérus. (Australasia). Calenia microcarpa Vzda [Syn.: Bullatina microcarpa (Vda) Brusse] is included in Gyalectidium as G. microcarpum (Vzda) Lücking, Sérus. & Vzda comb, nov., and G. catenulatum (Cavalc. & A. A. Silva) Ferraro, Lücking & Sérus. is treated as a species different from G. ftlicinum . Gyalectidium corticola Henssen is transferred to Calenia as Calenia corticola (Henssen) Ferraro, Lücking & Sérus. comb. nov. A key to all 29 accepted species of Gyalectidium is provided. The infrageneric phylogeny is constructed by means of a phenotype-based cladistic analysis, and the systematic affinities of the genus are discussed, accompanied by notes on the distribution and ecology of the species. Apothecia are not yet known in several species, including new ones. 相似文献
115.
ABSTRACT A bibliographic review on the Korean mosquitoes (Diptera: Culicidae) resulted in the recognition of 51 species and two forms of adult mosquitoes belonging to 10 genera, three subfamilies. Revised keys to genera and species of female adults of Korean mosquitoes are provided using available macro-characters. Pictorial keys are also provided for easy usage. 相似文献
116.
Alice Wells 《Australian Journal of Entomology》2002,41(3):221-225
Abstract Three new species are described in the endemic Australian microcaddisfly genus Orphninotrichia Mosely (Trichoptera: Hydroptilidae: Hydroptilinae), all collected in the Barrington Tops area of north-eastern New South Wales: Orphninotrichia bilobata sp. n., O. claviculata sp. n. and O. dundungra sp. n. From the same area, Orphninotrichia papillata Wells, described from central Victoria, is newly recorded and noted for the atypical presence of a large gland on the dorsum of the male head. Comments are made on the still unresolved affinities of the genus Orphninotrichia , and a key to males of all species is provided. 相似文献
117.
118.
Comparison of the results of two methods for species recognition, an egg identification key and rearing of larvae, showed only small qualitative differences in the identification of fish species present in a stretch of the River Elbe, Germany. Both the identification key and rearing methods complement each other as methods of identification, and the selection of which method to be used should depend primarily on the aim of the investigation. 相似文献
119.
【目的】从基因水平探究枯草芽孢杆菌渗透压调节因子L-脯氨酸合成途径中glnA、proB、proA基因的功能,通过分子改造实现对代谢途径的人工扰动。【方法】从枯草芽孢杆菌WB600出发,通过向胞内引入一系列基因敲除或过表达,分别构建了proB和proA基因过表达的重组菌WB601和WB602、glnA基因缺失的重组菌WB603以及在此基础之上过表达proB基因的重组菌WB604。借助菌株胞外和胞内游离脯氨酸积累的表型分析影响途径的关键节点。【结果】在非胁迫条件下,重组菌WB601和WB602胞外脯氨酸含量分别是原始菌的2.21倍和2.82倍,单位细胞胞外脯氨酸得率分别是原始菌的4.09倍和9.80倍,胞内游离脯氨酸含量分别是原始菌的1.91倍和3.34倍;重组菌WB603胞外脯氨酸含量上升至1221.43 mg/L,是原始菌的6.28倍,单位细胞胞外和胞内游离脯氨酸得率分别为原始菌的9.13倍和3.66倍;而重组菌WB604胞外脯氨酸含量最高达1391.65 mg/L,相比菌株WB603,其胞外脯氨酸含量及单位细胞得率分别提高了13.94%和14.10%,且胞内游离脯氨酸含量提高了32.60%。在5%Na Cl胁迫条件下,重组菌WB601和WB602的胞外脯氨酸含量分别是原始菌的1.94倍和1.54倍,单位细胞胞外脯氨酸得率分别是原始菌的2.15倍和2.19倍;重组菌WB603胞外脯氨酸含量及其单位细胞得率分别是原始菌的4.16倍和7.29倍;相同条件下,相比于重组菌WB603,重组菌WB604的胞外脯氨酸含量及其单位细胞得率分别提高了32.61%和5.54%。此外,实验组菌株的胞内游离脯氨酸含量均高于非胁迫时,并达到相对平衡状态。【结论】proB和proA基因的过表达均能显著提升细胞合成脯氨酸的能力,并且能增强细胞的耐盐性;glnA基因的缺失能增强脯氨酸合成途径,提高脯氨酸的积累;两种效应的正向叠加可进一步提升细胞脯氨酸合成能力。 相似文献
120.