首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   842篇
  免费   146篇
  国内免费   82篇
  2024年   1篇
  2023年   29篇
  2022年   53篇
  2021年   25篇
  2020年   35篇
  2019年   40篇
  2018年   26篇
  2017年   32篇
  2016年   49篇
  2015年   68篇
  2014年   99篇
  2013年   131篇
  2012年   61篇
  2011年   78篇
  2010年   34篇
  2009年   19篇
  2008年   30篇
  2007年   33篇
  2006年   22篇
  2005年   18篇
  2004年   20篇
  2003年   13篇
  2002年   19篇
  2001年   11篇
  2000年   10篇
  1999年   11篇
  1998年   9篇
  1997年   6篇
  1996年   4篇
  1995年   4篇
  1994年   6篇
  1993年   29篇
  1992年   7篇
  1991年   3篇
  1990年   7篇
  1989年   4篇
  1988年   2篇
  1987年   1篇
  1986年   3篇
  1985年   1篇
  1984年   2篇
  1983年   2篇
  1982年   7篇
  1979年   1篇
  1977年   2篇
  1973年   3篇
排序方式: 共有1070条查询结果,搜索用时 15 毫秒
61.
Two new species are added to the rare pompilid genus Abernessia Arlé. Abernessia capixaba sp. n. and A. giga sp. n. are described and illustrated. This is the first record of the genus from the states of Espírito Santo and Minas Gerais, Brazil. The genus now contains four species. A brief discussion of generic characters, illustrations, and a key to the known species of Abernessia are provided.  相似文献   
62.
Nine genera and twenty-two species of heptageniid mayflies from Thailand are defined in this present work as well as one suggested further subgenus, Compsoneuria (Siamoneuria) kovaci (species “incertae sedis”) including some particular characters. Taxonomic remarks, diagnoses, line drawings of key characters, distribution, habitat and biological data, and a larval key to the genera and species are provided. The chorionic eggs of eight genera and eight species were observed and shown using a scanning electron microscope.  相似文献   
63.
64.
65.
Two new species of oribatid mites of the genus Lasiobelba (Oribatida, Oppiidae), Lasiobelba (Lasiobelba) daamsae sp. n. and Lasiobelba (Antennoppia) nepalica sp. n., are described from eastern Nepal. Lasiobelba (L.) daamsae sp. n. is most similar to L. (L.) remota Aoki, 1959 and L. (L.) gibbosa (Mahunka, 1985), however, it differs from both by the anterior part of pedotecta I specifically curved, rostrum pointed and exobothridial setae not shorter than bothridial setae. Lasiobelba (Antennoppia) nepalica sp. n. is most similar to L. (A.) granulata (Mahunka, 1986), however, it differs from the latter by the larger body size, exobothridial setae longer than rostral setae and bothridial setae not longer than interlamellar setae. An identification key to known species of Lasiobelba is given.  相似文献   
66.
An update on the taxonomy and geographic distribution of the genus Thymus in Sicily is given. This study is based on literature, herbarium and field investigations. In total, five taxa belonging to Thymus sect. Serpyllum (Th.richardii subsp. nitidus, Th.longicaulis and Th.praecox subsp. parvulus) and Th. sect. Hyphodromi (Th.spinulosus and Th.paronychioides) occur in Sicily. For each one, information about taxonomy, habitat, phenology, chromosome number and distribution are provided. Furthermore, the name Thymus pedicillatus Lojac. is here typified. Finally, an analytical key for the identification of the studied taxa is proposed.  相似文献   
67.
Thirteen species of Pyrrhalta Joannis, 1865 with black elytron are reviewed. A key to species, photographs of aedeagus and habitus are provided. Pyrrhalta qianana sp. n. is described from Guizhou, China. Pyrrhalta martensi Medvedev & Sprecher-Uebersax, 1999 is newly recorded from China (Tibet).  相似文献   
68.
In Argentina, five genera and 14 species are recorded in the subfamilies Prostemmatinae and Nabinae: Hoplistoscelis sordidus Reuter, Lasiomerus constrictus Champion, Metatropiphorus alvarengai Reuter, Nabis argentinus Meyer-Dür, Nabis (Tropiconabis) capsiformis Germar, Nabis faminei Stål, Nabis paranensis Harris, Nabis punctipennis Blanchard, Nabis roripes Stål, Nabis setricus Harris, Nabis tandilensis Berg, Pagasa (Pagasa) costalis Reuter, Pagasa (Lampropagasa) fuscipennis Reuter and Pagasa (Pagasa) signatipennis Reuter.  相似文献   
69.
In this study, we revise the lace bugs (family Tingidae) from the Ogasawara Islands, Japan (also known as the “Oriental Galapagos”). Three species belonging to two endemic genera are recognized: Acanthomoplax tomokunii gen. et sp. nov. , Omoplax desecta (Horváth, 1912), and O. majorcarinae Guilbert, 2001. A key to species is provided to facilitate the identification of Ogasawaran lace bugs.  相似文献   
70.
In Argentina, 10 genera and 33 species of Stenopodainae (Hemiptera: Reduviidae) have been recorded. Diagnoses of the genera, subgenera and species are given, and an illustrated key to genera is provided. Six species are new records for Argentina and an additional seven species represent new records for provinces.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号