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991.
Illegal hunting has been a major threat for the survival of wildlife fauna, including the three crocodile species that India harbours: Crocodylus palustris, Crocodylus porosus and Gavialis gangeticus. Although law prevents trade on these species, illicit hunting for trade continues to threaten the survival of these endangered species; conservation strategies therefore require a rapid molecular identification technique for Indian crocodiles. A multiplex polymerase chain reaction (PCR) assay with species-specific primers, considered as one of the most effective molecular techniques, is described herein. The primers were designed to yield species-specific sized amplicons. The assay discriminates the three Indian crocodile species unambiguously within a short time period using only simple agarose gel electrophoresis. We recommend this multiplex PCR assay to be used in the identification of Indian crocodile species. 相似文献
992.
Seung Bum Sohn Tae Yong Kim Jong Myoung Park Sang Yup Lee Professor 《Biotechnology journal》2010,5(7):739-750
Genome-scale metabolic models have been appearing with increasing frequency and have been employed in a wide range of biotechnological applications as well as in biological studies. With the metabolic model as a platform, engineering strategies have become more systematic and focused, unlike the random shotgun approach used in the past. Here we present the genome-scale metabolic model of the versatile Gram-negative bacterium Pseudomonas putida, which has gained widespread interest for various biotechnological applications. With the construction of the genome-scale metabolic model of P. putida KT2440, PpuMBEL1071, we investigated various characteristics of P. putida, such as its capacity for synthesizing polyhydroxyalkanoates (PHA) and degrading aromatics. Although P. putida has been characterized as a strict aerobic bacterium, the physiological characteristics required to achieve anaerobic survival were investigated. Through analysis of PpuMBEL1071, extended survival of P. putida under anaerobic stress was achieved by introducing the ackA gene from Pseudomonas aeruginosa and Escherichia coli. 相似文献
993.
994.
Nathaniel D. Maynard Miriam V. Gutschow Elsa W. Birch Markus W. Covert Professor 《Biotechnology journal》2010,5(7):686-694
Recent genome-wide screens of host genetic requirements for viral infection have reemphasized the critical role of host metabolism in enabling the production of viral particles. In this review, we highlight the metabolic aspects of viral infection found in these studies, and focus on the opportunities these requirements present for metabolic engineers. In particular, the objectives and approaches that metabolic engineers use are readily comparable to the behaviors exhibited by viruses during infection. As a result, metabolic engineers have a unique perspective that could lead to novel and effective methods to combat viral infection. 相似文献
995.
KAISER D. SCHWARCZ CAIAME L. PATACA ALUANA G. ABREU JOICE M. BARIANI CAMILA M. T. MACRINI VERA N. SOLFERINI 《Botanical journal of the Linnean Society. Linnean Society of London》2010,164(3):326-336
We explore the genetic structure and variability in autochorous Metrodorea nigra (Rutaceae) and anemochorous Astronium graveolens (Anacardiaceae), two species affected by deforestation in the Atlantic Forest of Brazil. The effects of deforestation and the depletion of the habitat within the remaining patches of forest are evaluated by comparing the variability between saplings and adults of each of these two species. The results indicate that the depletion of forest land and the deteriorating condition of the remaining fragments of forest may reduce the level of endogamous breeding in wind‐dispersed species. In autochorous species, the fragmentation of forest land has less notable effects on genetic attributes, but pollen flow could be decreased as a result of the reduced number of insects flying between the forest remnants. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164 , 326–336. 相似文献
996.
SARAH ELTON JASON DUNN ANDREA CARDINI 《Biological journal of the Linnean Society. Linnean Society of London》2010,101(4):823-843
Subspecific variation is widespread in vertebrates. Within Africa, several mammals have extensive geographic distributions with attendant morphological, ecological, and behavioural variations, which are often used to demarcate subspecies. In the present study, we use a primate species, the vervet monkey, Cercopithecus aethiops, as a case study for intraspecific divergence in widespread mammals, assessed through hard tissue morphology. We examine intraspecific differences in size, shape, and non‐allometric shape from a taxonomic perspective, and discuss the macroevolutionary implications of findings from microevolutionary analyses of geographic variation. A geometric morphometric approach was used, employing 86 three‐dimensional landmarks of almost 300 provenanced crania. Many of the taxonomic differences in skull morphology between vervet populations appear to be related to geographic proximity, with subspecies at opposite extremes of a west‐to‐east axis showing greatest divergence, and populations from central and south Africa being somewhat intermediate. The classification rate from discriminant analyses was lower than that observed in other African primate radiations, including guenons as a whole and red colobus. Nonetheless, taxonomic differences in shape were significant and not simply related to either geography or size. Thus, although shifts in size may be an important first step in adaptation and diversification, with size responding more quickly than shape to environmental change, the six vervet taxa currently recognized (either as species or subspecies) are not simply allometrically scaled versions of one another and are probably best viewed as subspecies. Holding allometry constant when examining inter‐population differences in shape may thus help to reveal the early stages of evolutionary divergence. The vervet case study presented here hence has relevance for future studies examining intraspecific differentiation in other large mammals, particularly through the methods used to identify small but biologically meaningful divergence, with attendant implications for conservation planning. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 823–843. 相似文献
997.
998.
BERNHARD A. HUBER NADINE FISCHER JONAS J. ASTRIN 《Zoological Journal of the Linnean Society》2010,158(2):244-299
This study describes the remarkable radiation of Modisimus on Hispaniola. During two short trips to the island, more species have been collected than are known from any comparable area on the mainland. We redescribe three of the four previously known Hispaniolan species, and describe 22 new species. Most Haitian species are local endemics, either of the severely threatened forests in one of the two national parks (La Visite National Park and Macaya Biosphere Reserve) or of their surrounding areas. Phylogenetic analysis indicates that most of these species together represent a species group that is restricted to the paleogeographically distinct southern ‘paleoisland’, and that is otherwise known neither from Hispaniola nor from any other island. Two mitochondrial markers, 16S and cytochrome oxidase I (COI), were sequenced in 21 species to test for their performance as barcoding genes within this group of partly closely related species. Both markers unambiguously corroborated the morphospecies, with small but distinct gaps between the intra‐ and interspecific genetic distances. The absence of Modisimus in South America argues against colonization of the West Indies over a ‘landspan’ connecting South America to the Greater Antilles. Overwater dispersal is supported by two lines of evidence (unusual radiation and reduced higher‐level diversity), but further data (especially time estimates for the separation of mainland and island taxa) are needed to evaluate the third major model, continent–island vicariance as a result of plate tectonics. The species diversity of the genus, combined with the presence of habitat specialists, suggests that this system may have the potential to complement the classic studies on adaptive radiation in Caribbean Anolis lizards. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 244–299. 相似文献
999.
1000.
广东省南昆山伯乐树群落特征及其保护策略 总被引:5,自引:0,他引:5
在广东省南昆山自然保护区内调查了中国特有珍稀植物伯乐树种群的分布格局、龄级结构和伴生群落的物种组成.结果表明:该种群的分布范围狭窄且集中;龄级不完整,Ⅱ、Ⅲ级幼树少见,结构呈衰退型;伴生群落呈典型的亚热带植物区系的特点,其组成不稳定、优势种不显著.建议将伯乐树幼树作为就地保护的重点,适当去除周围的罗浮槭、羊角杜鹃和黄樟等速生树种,以创造有光照和水肥条件的生境;对于Ⅳ级以上成株,应注意拟赤杨和华润楠等空间生态位相近树种的数量和密度,适当疏剪枝条,以帮助成株占据较好的空间位;同时再积极引入异龄的伯乐树幼苗,促进种群恢复和发展. 相似文献