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111.
As shown in Part I, the Vespertilioninae have on the average the lowest encephalization index (EI) of all the Vespertilionid subfamilies available, and the average size indices (Sis) of most of their brain parts are also lowest. There are, however, clear differences between the genera. The highest indices for the total brain and for many brain parts (OBL, DIE, TEL, PAL, SEP, STR, SCH) were found in Myotis, the highest Sis for NEG and MES in Scotophilus, for CER in Lasiurus, for BOL in Rhogeessa, and for HIP in Cbalinolobus. The lowest values for all brain parts except BOL were found in Tylonycteris (for BOL in Glauconycteris). The average EI of the flat-headed bamboo bats Tylonycteris pachypus and T. robustula was 60, i. e., 2/5 less than that of the non-Tylonycteris Vespertilionids, which, as the reference group, have an average EI of 100. The brain size reduction may well be related to the adaptation to extreme flat-headedness. The amount of reduction in the various brain parts differs: it is strongest (about 1/2) in higher but more dispensable brain parts (STR, HIP, NEO) and distinctly lower (about 1/4) in structures closely involved in the fundamental vegetative functions (OBL, MES). Genera with conservative skull characteristics may have derivative characteristics of the brains, and vice versa.  相似文献   
112.
113.
Seed dispersal is an ecological process crucial for forest regeneration and recruitment. To date, most studies on frugivore seed dispersal have used the seed dispersal effectiveness framework and have documented seed-handling mechanisms, dispersal distances and the effect of seed handling on germination. In contrast, there has been no exploration of “disperser reliability” which is essential to determine if a frugivore is an effective disperser only in particular regions/years/seasons or across a range of spatio-temporal scales. In this paper, we propose a practical framework to assess the spatial reliability of frugivores as seed dispersers. We suggest that a frugivore genus would be a reliable disperser of certain plant families/genera if: (a) fruits of these plant families/genera are represented in the diets of most of the species of that frugivore, (b) these are consumed by the frugivore genus across different kinds of habitats, and (c) these fruits feature among the yearly staples and preferred fruits in the diets of the frugivore genus. Using this framework, we reviewed frugivory by the genus Macaca across Asia to assess its spatial reliability as seed dispersers. We found that the macaques dispersed the seeds of 11 plant families and five plant genera including at least 82 species across habitats. Differences in fruit consumption/preference between different groups of macaques were driven by variation in plant community composition across habitats. We posit that it is essential to maintain viable populations of macaques across their range and keep human interventions at a minimum to ensure that they continue to reliably disperse the seeds of a broad range of plant species in the Anthropocene. We further suggest that this framework be used for assessing the spatial reliability of other taxonomic groups as seed dispersers.  相似文献   
114.
陈小姝  谷硕  宋晓霞  李姝  王琦  李玉 《菌物学报》2011,30(5):799-807
为调查长春地区黏菌资源的物种多样性,便于掌握长春地区黏菌资源情况,对长春地区的黏菌进行了为期3年的系统调查,共采集到标本2,000余份,通过形态特征鉴定为5目7科23属59种。团毛菌科、绒泡菌科和发网菌科为优势科,共计49种,占长春地区黏菌总种数的83.1%,科的数目占总科数的42.8%。团网菌属、半网菌属、团毛菌属、绒泡菌属和发网菌属为优势属,共计34种,占总种数的57.6%。从种的组成上可以划分为世界广布种(67.8%),北温带分布种(10.17%),东亚-北美洲间断分布种(5.08%),温带-亚热带  相似文献   
115.
亚洲中部荒漠区的植物特有属   总被引:22,自引:0,他引:22  
赵一之  朱宗元 《云南植物研究》2003,25(2):113-121,122
系统地列出了亚洲中部荒漠区的13个植物特有属或近特有属——绵刺属、沙冬青属、四合木属、百花篙属、革苞菊属、河西菊属、喀什菊属、紊篙属、连蕊芥属、钝基草属、合头黎属、戈壁黎属、霸王属。这些属都是单种属或双种属,分类上属于孤立的类群;演化系统上是既起源古老而又进化的类群;生态上都是早生植物,绝大多数是荒漠种,其生活型灌木和半灌木占优势;地理分布上阿拉善荒漠区是其特有属的分布中心;起源上是多元的。  相似文献   
116.
Li  Yu. V.  Terekhova  L. P.  Gapochka  M. G. 《Microbiology》2002,71(1):105-108
A new method employing extremely high frequencies (EHFs) is proposed for the selective isolation of actinomycetes from soil. The pretreatment of soil suspensions with EHF wavelengths of 5.6 and 7.1 mm led to a nonselective isolation of actinomycetes. At the same time, the irradiation of soil suspensions within wavelength bands of 3.8–5.8 and 8–11.5 mm considerably augmented the total number of isolated actinomycetes and increased the fraction of the isolated rare genera by 2 and 7 times, respectively. The rare actinomycete genera were represented by Actinomadura, Microtetraspora, Nonomuraea, Micromonospora, Amycolatopsis, Pseudonocardia, Saccharotrix, and Streptosporangium.  相似文献   
117.
Singchia Z. J. Liu & L. J. Chen, a new orchid genus, is established based on the new species S. malipoensis Z. J. Liu & L. J. Chen found in southeast Yunnan, China. The new genus is related to Pteroceras, from which it differs by having a lip with its basal margins immovably adnate to the lower part of the pendent column foot, a thin-walled spur, and very unequally and deeply split pollinia, each with a distinct caudicle. In addition to a discussion on Ascocentrum pusillum, a species of questionable placement, another new genus, namely Gunnaria S. C. Chen ex Z. J. Liu & L. J. Chen, is set up and a new combination, namely G. pusilla (Aver.) Z. J. Liu & L. J. Chen, is made. The new genus Gunnaria differs from its allyAscocentrum by having a cross-shaped pollinarium, sulcate or split pollinia, each with a distinct caudicle attached to a common linear stipe much longer than either pollinia or viscidium, and strongly incurved side lobes of the lip.  相似文献   
118.
对大兴安岭硅藻进行了形态分类学研究, 发现了部分中国新记录属及中国新记录种。研究共报道大兴安岭硅藻10属10种, 对这些属、种的形态学特征进行了详细的描述, 并提供了图片资料。其中3个属为中国新记录属, 分别为: 北方藻属Boreozonacola Lange-Bertalot、Kulikovskiy Witkowski、矮羽纹藻属Chamaepinnularia Lange-Bertalot Krammer、微肋藻属Microcostatus Johansen Sray。本文给出其余7个属的详细特征描述, 为其他相关研究提供参考。观察到中国新记录种9种1变种, 分别为: 胡斯特北方藻Boreozonacola hustedtii Lange-Bertalot, Kulikovskiy Witkowski、海塞矮羽纹藻Chamaepinnularia hassiaca (Krasske) Cantonati Lange-Bertalot、墙生微肋藻Microcostatus maceria (Schimanski) Lange-Bertalot、异辐节卡维藻Cavinula heterostauron (Germain) Van de Vijver、类印加等列藻Diadesmis ingeaeformis Hamilton Antoniades、沼地盖斯勒藻Geissleria paludosa (Hustedt) Lange-Bertalot Metzeltin、忽视蹄形藻Hippodonta neglecta Lange-Bertalot, Metzeltin Witkowski、沙拉泥生藻Luticola charlatii (Peragallo) Metzeltin, Lange- Bertalot、原子麦尔藻特许变种Mayamaea atomus var. permitis (Hustedt) Lange-Bertalot、莱维迪细篦藻Neidiopsis levanderi (Hustedt) Lange-Bertalot Metzeltin。    相似文献   
119.
为了研究神农架世界自然遗产地的种子植物区系特征,基于Phylomatic建立时间树并综合多学科证据,探讨了该区系种子植物科属起源的时间特征。结果发现,神农架世界自然遗产地裸子植物占中国华中山地分布中心属和种的67%和74%,是中国裸子植物分布中心之一;被子植物科的基部类群科占中国的85%;种子植物单型科(仅含1属1种)占中国的42%;拥有中国特有属56属,占中国特有属总数的23%,很多为古老特有属;神农架世界自然遗产地还分布有中国超过50%的东亚-北美间断分布属。这些事实表明神农架世界自然遗产地种子植物区系起源古老,且有连续的传代线,是神农架世界自然遗产地突出普遍价值的重要体现。  相似文献   
120.
A new genus and species of sea pen or virgulariid pennatulacean from the Gulf of Guinea in the tropical eastern Atlantic is described, and a key to the genera of the Virgulariidae is included. The new genus and species described here adds to the previously described five other genera of the family. It is distinguished by unique sclerite and polyp leaf characters from the superficially-similar genus Virgularia, which lacks conspicuous sclerites in the polyp leaves and coenenchyme (other than minute oval bodies that are generally <0.01 mm in length).  相似文献   
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