全文获取类型
收费全文 | 1217篇 |
免费 | 13篇 |
国内免费 | 18篇 |
专业分类
系统科学 | 32篇 |
丛书文集 | 20篇 |
教育与普及 | 4篇 |
理论与方法论 | 10篇 |
现状及发展 | 14篇 |
综合类 | 1045篇 |
自然研究 | 123篇 |
出版年
2024年 | 1篇 |
2023年 | 5篇 |
2022年 | 5篇 |
2021年 | 6篇 |
2020年 | 8篇 |
2019年 | 8篇 |
2018年 | 6篇 |
2017年 | 10篇 |
2016年 | 12篇 |
2015年 | 25篇 |
2014年 | 57篇 |
2013年 | 55篇 |
2012年 | 181篇 |
2011年 | 95篇 |
2010年 | 86篇 |
2009年 | 74篇 |
2008年 | 67篇 |
2007年 | 63篇 |
2006年 | 58篇 |
2005年 | 40篇 |
2004年 | 45篇 |
2003年 | 34篇 |
2002年 | 26篇 |
2001年 | 39篇 |
2000年 | 22篇 |
1999年 | 21篇 |
1998年 | 20篇 |
1997年 | 21篇 |
1996年 | 21篇 |
1995年 | 22篇 |
1994年 | 17篇 |
1993年 | 17篇 |
1992年 | 24篇 |
1991年 | 15篇 |
1990年 | 6篇 |
1989年 | 10篇 |
1988年 | 9篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 6篇 |
1984年 | 2篇 |
排序方式: 共有1248条查询结果,搜索用时 9 毫秒
41.
相对于传统耳听手记的声调研究方法,实验语音学的方法使得声调研究结果更加客观化.烟台方言可以分为老派和新派方言,它们的单字调声调在某种程度上存在着不同.就目前来讲,对新派烟台方言研究相对较少,尤其是实验的方法,几乎还是空白.应用现代实验语音学的方法,侧重整个实验过程和实验数据,测算出新派烟台方言单字调调类最终分为三类,调类与调值分别为:乎声44,上声313,去声42.由于这一结果与传统烟台方言单字调调值有较大差异,故本文对新派烟台方言单字调与传统烟台方言研究结果及普通话也进行了比较,并在此基础上分析了新派烟台方言单字调调值可能演变的原因.新调值还有可能对烟台方言两字组及三字组连读变调模式产生影响. 相似文献
42.
中学田径教学的不景气,主要是因为教学方法的陈1El,教学内容的单一以及教学评价的不合理所造成的。要想改变这种局面,我们就必须在诸多方面更新理念、有所变革。 相似文献
43.
《华山畿》南朝乐府民歌是历来为人们所称颂的至爱至悲的千古绝唱,然而,关于其故事的发生地问题,迄今众说纷纭。或日“高淳华山”;或日“句容华山”。其实,依据《乐府诗集》、镇江地方志及有关实地考察等情况作全面辨析,可以断定:《华山畿》故事的发生地即在当今的镇江市新区石桥乡华山村。 相似文献
44.
文章对RSS技术及其内容的组织和发布做了详细的阐释,分析了高校图书馆采用RSS技术发布信息的九大特点,设计了图书馆信息服务流程图,并且总结了当前图书馆应用的RSS几种模式,指出了当前图书馆应用RSS信息服务模式存在的问题。 相似文献
45.
以记人事为主的《世说新语》以搜集民间故事为能事,同时肩负着补正史之阙的重任,从而使其成为侠义故事的一个重要归宿。仗义济世、快意恩仇、好勇尚武是《世说新语》侠义故事的三大主要类型。《世说新语》自身的文史价值,以及里面的侠客形象、人物刻画手法都对后代侠义小说的影响甚为深远。 相似文献
46.
47.
48.
M. J. Page 《Journal of Natural History》2018,52(17-18):1157-1180
Colonial ascidians collected from wharf piles and natural substrata from Bluff Harbour and Stewart Island in the South Island of New Zealand are described in this paper. Two species, Lissoclinum violaceum sp. nov. and Didemnum marineae sp. nov. are new to science and described for the first time. The ascidian fauna in this region is a mixed assemblage of southern species, species with a New Zealand-wide distribution, and two species with trans-Tasman affinities.
www.zoobank.org/urn:lsid:zoobank.org:pub:37DC0D4B-8FB9-4F1D-A5A0-E9CAB3203447 相似文献
49.
《Journal of Natural History》2012,46(9-10):509-522
Three hundred and ninety‐nine individuals representing 10 species of Litoria and five species of Nyctimystes (Hylidae), L. arfakiana, L. bibonius, L. eucnemis, L. genimaculata, L. impura, L. infrafrenata, L. modica, L. nasuta, L. thesaurensis, L. wollastoni, N. gularis, N. kubori, N. papua, N. pulcher and N. semipalmatus collected in Papua New Guinea were examined for helminths. Gravid individuals representing one species of Monogenea (Parapolystoma bulliense), one species of Digenea (Mesocoelium monas), 18 species of Nematoda (Aplectana krausi, Aplectana macintoshi, Aplectana zweifeli, Cosmocerca novaeguineae, Falcaustra papuensis, Icosiella papuensis, Maxvachonia adamsoni, Maxvachonia ewersi, Meteterakis crombiei, Moaciria moraveci, Ochoterenella papuensis, Oswaldocruzia bakeri, Parapharyngdon maplestoni, Parathelandros allisoni, Parathelandros andersoni, Physalopteroides milnensis, Rhabdias australiensis, Seuratascaris numidica) and one species of Acanthocephala (Acanthocephalus bufonis) were found. Also included were immature forms representing one species of Cestoda (as a metacestode), three species of Nematoda (Abbreviata sp., Rictulariidae gen. sp., Ascarididae gen. sp. in cysts), one species of Acanthocephala (unidentified cystacanth), and one species of Pentastomida [Raillietiella sp. (nymph)]. The mean helminth species richness for infected hosts was 1.3±0.6 SD (range one to three species). Sixty‐seven new host records and two new locality records are reported. 相似文献
50.
《Journal of Natural History》2012,46(6):697-778
The Neotropical species and genera of the tribe Euderomphalini (Eulophidae: Entedoninae) are revised. Five genera are described as new: Cabeza, including six species (baeostigma (§, ¦), canaliculata (§), laticeps (¦), petiolata (§), planiscapus (§), ugaldei (§)); Itahipeus, including two species (brasilicola (§, ¦), euryceps (¦)); Monterrondo, including one species (aphelosoma (§)); Sifraneurus, including one species (strigifer (§)); Xenopomphale, including one species (sulcata (§)); all above-mentioned species are described as new. Five additional genera are included: Aleuroctonus LaSalle and Schauff, with four species, one described previously: vittatus (Dozier) (§, ¦), and three described here: latiscapus (§), marki, (§, ¦) and metallicus (§); Entedononecremnus Girault, with 14 species, two described previously: krauteri Zolnerowich and Rose (§, ¦), unicus Girault (§, ¦), and 12 described here: bennetti (§, ¦), bimaculatus (§, ¦), convexus (§, ¦), crassicornis (§, ¦), depressus (§), fulgens (§), hansoni (§, ¦), imdasus (§, ¦), parfer (§, ¦), reticulatus (§), tripar (§) and unicarinatus (§); Euderomphale Girault, with two species, one described previously: flavimedia (Howard), and one described here: sulciscapus (§, ¦); Neopomphale LaSalle and Schauff, with 20 species, two described previously: aleurothrixi (Dozier) (§, ¦), quercicola (Dozier) (§, ¦), and 18 described here: azofeifai (¦), cerrobius (¦), depilis (§), dichrous (§, ¦), erecta (¦), graciliclava (§), longicornis (¦), longipilis (§, ¦), nonaequa (§, ¦), noyesi (§), pinguicornis (§, ¦), prymna (§), rubescens (§, ¦), rubii (§), silvestris (¦), transversa (§), umbonata (§, ¦), xenipennis (§); Dasyomphale LaSalle and Schauff, including one species (chilensis LaSalle and Schauff). The genera are placed in either one of three genus-groups, one of which is newly created. The species Euderomphale quercicola Dozier is newly combined to Neopomphale. Lectotypes are designated for Entedononecremnus unicus Girault, Euderomphale quercicola Dozier and Gyrolasia flavimedia Howard. Key to genera and species are included. 相似文献