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141.
A new species, Goffartia phalacra n. sp. is described and illustrated. The body is thin and slender with L = 511 to 646 μm; a = 37.1 to 47.4; b = 4.8 to 6; c = 2.6 to 4.8; c′ = 13.6 to 32.8; V = 40% to 49% in females. Males are smaller but similar to females and the posterior region is strongly curved. The species is characterized by a tubular stoma, a smooth round lip region, anterior pharynx much smaller than posterior pharynx, two pairs of unicellular glands associated with the vagina, and males with a broad keel-shaped gubernaculum. G. phalacra n. sp. can be differentiated from all other species of the genus by its lip region and the structure of the gubernaculum. This is the first instance of a species of Goffartia occurring in a terrestrial habitat and the first report of a species from India.  相似文献   
142.
The systematics of the order Tubulidentata is poorly known. Its phylogeny has never been thoroughly analysed and only a single review has ever been performed, which was over 30 years ago. This situation has hampered palaeoecological and palaeobiogeographical studies of these Neogene mammals. The present revision of the Orycteropodidae deals with the phylogeny and systematics of all African and Eurasian species over the last 20 Myr. The first comprehensive cladistic analysis of the family is presented here. The results of this analysis, based on 39 coded morphological characters, supplemented by non‐coded features taken from all over the skeleton, was used to reconstruct the phylogeny of the order Tubulidentata. Two distinct lineages within the genus Orycteropus are recognized and characterized. The new genus Amphiorycteropus is subsequently created, in order to harmonize taxonomy and phylogeny. The fossil genera Leptorycteropus and Myorycteropus are validated, bringing the number of genera in the order Tubulidentata to four. Moreover, within the family Orycteropodidae, the number of confirmed species is now 14. The outcome of this study allows us to propose a consistent palaeobiogeographical scenario for aardvarks. Finally, this revision represents the most comprehensive work on the evolutionary history of the order Tubulidentata to date, and provides a new framework for future studies. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 649–702.  相似文献   
143.
研究了我国蜗寄蝇族瑟寄蝇属Cyrtophleba(双翅目:寄蝇科)2种,其中茹瑟寄蝇Cyrtophleba ruricola 分布于辽宁,山西,宁夏,新疆;变瑟寄蝇Cyrtophleba vernalis为中国新记录种,分布于辽宁。给出了上述2种的鉴别特征及变瑟寄蝇头和雄性尾器的特征图。研究标本分别保存于沈阳师范大学昆虫标本室(SYNU),中国科学院动物研究所(IZCAS)和国家林业局森林病虫害防治总站(GSFPM)。  相似文献   
144.
145.
核糖体转录间隔子2应用于鱼类种属的鉴别   总被引:3,自引:0,他引:3  
袁万安 《遗传》2010,32(4):369-374
为了防止珍稀鱼类的非法捕捞和销售, 鱼类种属的鉴别就成为非常关键的问题, 特别是形态学方法无法区分的样品(如鱼苗、鱼鳞、鱼卵、鱼肉及其加工产品等)。为了帮助珍稀鱼类资源的管理和保护, 文章报道了一种利用核糖体基因的转录间隔子2鉴别鱼类种属的分子遗传学方法: (1) 利用同一目鱼类5.8S rRNA和28S rRNA基因的保守性, 设计出扩增鲤形目鱼类这两个基因间转录间隔子2 DNA片段, 测序获得它们的碱基排列顺序; (2) 再根据不同鱼类转录间隔子2序列的差异, 设计出每种鱼的种属特异引物、种属鉴别标准物, 构建鱼类分子分类图谱, 利用PCR复合扩增技术鉴别鱼类种属。通过对国内不同地方采集的5种鲤形目鱼类的210个单一品种样本和40个混合样本的鉴别检验, 该方法能够准确、灵敏和快速鉴别这5种鱼, 可用于鱼类资源保护和评估、管理和开发, 特别是在渔业管理人员渔业执法、海关打击珍稀鱼类走私、防止商业欺诈和外来有害生物入侵等方面非常有用  相似文献   
146.
The Neotropical-African liverwort Marchesinia brachiata has long been regarded as a polymorphic species. This hypothesis is examined using a dataset including sequences of the nuclear internal transcribed spacer region and the plastidic trnL–trnF region of 39 Marchesinia accessions. Maximum parsimony, maximum likelihood and Bayesian analyses indicate that Marchesinia robusta is nested within M. brachiata s.l. The molecular topologies support at least three partly sympatric biological species within M. brachiata s.l., the Neotropical M. bongardiana and M. languida, and the Neotropical-African M. brachiata s.s. These species are incompletely separated by subtle differences in underleaf shape and leaf dentation. Long branches within M. brachiata s.s. suggest ongoing speciation processes that are not yet reflected in distinguishable morphological variation. Divergence time estimates based on nrITS sequence variation and the liverwort fossil record indicate an establishment of the species M. bongardiana, M. brachiata, M. languida, M. madagassa, and M. robusta in the Late Oligocene and Miocene. The intraspecific diversity shows distinctive patterns with evidence for constant accumulation of genetic diversity in M. robusta and M. brachiata whereas M. bongardiana and M. languida likely went through a recent extinction or expansion process as indicated by the bottleneck pattern of genetic diversity. The tropical American-African disjunction of M. brachiata is the result of dispersal rather than Western Gondwanan vicariance.  相似文献   
147.
Chinese species in the genus Nycheuma Fennah, 1964a (Hemiptera: Fulgoromorpha: Delphacidae: Delphacinae: Delphacini) are revised to include three species: Nycheuma cognatum (Muir, 1917), Nycheuma dimorpha (Matsumura, 1910) and Nycheuma nilotica Linnavuori, 1973. Nycheuma coctum Yang, 1989 is placed in synonymy with Nycheuma nilotica Linnavuori, 1973. Nycheuma dimorpha (Matsumura, 1910) is newly recorded from China. The generic characteristics are redefined. The main morphological characters, male genitalia of 3 species are described or redescribed and illustrated. A key to Chinese species in the genus is provided.  相似文献   
148.
A new species, Triplophysa huapingensis, is described from the Hongshuihe River, Guangxi, China. The new species is distinguished from other species of Triplophysa by the following combination of characters: body covered with scales, lateral line complete, eyes not degenerate, dorsal fin truncate, caudal fin forked, tip of pelvic fin not reaching anus, eight branched rays of dorsal fin, six branched rays of pelvic fin, 16 branched rays of caudal fin, grey and black diffused blotches on dorsal and lateral head and body. A key to all recorded species of Triplophysa in the Xijiang River system is provided.  相似文献   
149.
高燕  刘斯宇  杨光  姚云志  任东 《昆虫知识》2012,49(2):543-555
本文详细总结和回顾了世界毛翅目化石研究简史,列出已发表的化石种类名录、分布及年代,共37科、193属、661种(包括中国发现的4科9属15种),描述了不同地质时期主要毛翅目化石的分类单元和分布地区。简要介绍了毛翅目分类系统及系统发育、不同地质时期毛翅目化石的产地及时代。初步分析了目前该类群所存在的一些问题,并对今后的研究工作进行了展望。  相似文献   
150.
对分离所得小囊菌科(Microascaceae)4属6种进行了形态学研究,明确了闭小囊菌属(Kernia)在中国大陆的分布,并以检索表形式比较了中国已报道小囊菌科5个属的形态学特征。  相似文献   
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