全文获取类型
收费全文 | 66篇 |
免费 | 2篇 |
出版年
2013年 | 1篇 |
2011年 | 2篇 |
2010年 | 2篇 |
2009年 | 1篇 |
2008年 | 1篇 |
2007年 | 2篇 |
2006年 | 3篇 |
2005年 | 3篇 |
2004年 | 1篇 |
2001年 | 1篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1972年 | 1篇 |
1971年 | 2篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1965年 | 1篇 |
1960年 | 1篇 |
1959年 | 1篇 |
1958年 | 3篇 |
1957年 | 1篇 |
1956年 | 3篇 |
1954年 | 1篇 |
1953年 | 1篇 |
1952年 | 2篇 |
1951年 | 1篇 |
1950年 | 2篇 |
1949年 | 2篇 |
1948年 | 1篇 |
1947年 | 1篇 |
1946年 | 1篇 |
1945年 | 2篇 |
排序方式: 共有68条查询结果,搜索用时 31 毫秒
1.
2.
3.
Franz Boas spent several weeks at Fort Rupert, British Columbia, at the end of 1894, when he saw the Kwakiutl hamatsa ritual in situ for the first time. Soon after his return east Boas posed for a series of photographs in the U.S. National Museum for a diorama of the hamatsa dance. These photographs, now published for the first time, are a sharp reminder of Boas' constant (and sometimes forced) collaboration with the limited number of anthropological institutions in America at the end of the century, and of his personal difficulties in establishing himself professionally in America. 相似文献
4.
DITTE HOLM ANDERSEN ELENA FABBRI ALBERTO SANTINI SANDRINE PAGET EDOUARD CADIEU FRANCIS GALIBERT CATHERINE ANDR ETTORE RANDI 《Molecular ecology resources》2006,6(4):1184-1187
We characterized 59 canine single nucleotide polymorphisms (SNPs) in the endangered Italian wolf (Canis lupus) population, which were discovered by resequencing sequence‐tagged‐site (STS) DNA sequences that are known to contain SNPs in domestic dogs. Dog SNPs were usually found also in wolves. Additional SNPs unique in dogs or wolves were discovered, which is important for detecting hybrids between dogs and wolves. We developed new primer sets and analysed 15 SNPs by Pyrosequencing. The characterized SNPs will provide an important addition to the genetic markers that are currently available for studying wild populations of canids. 相似文献
5.
Abstract The herbicides DCMU, bentazon, amitrole, and SAN 6706 were tested for their ability to influence the carotenoid and pro-tochlorophyll(ide) composition as well as the protochloro-phyll(ide) phototransformation and the Shibata shift in dark-grown radish seedlings (Raphanus sativus L. cv. Saxa Treib). Bentazon enhanced the formation of lutein and carotenes, while SAN 6706 suppressed the biosynthesis of carotenoids. Amitrole led to a reduced accumulation of phototransformable pro-tochlorophyll(ide). The phototransformation of pro-tochlorophyll(ide) and the Shibata shift were not affected by any of the tested herbicides, irrespective of the presence or absence of activated phytochrome. From this we conclude that herbicides inhibiting photosystem II or producing chlorosis partly affect, but do not block, carotenoid and chlorophyll biosynthesis in dark-grown plants. The main herbicide effect becomes visible only after prolonged illumination. 相似文献
6.
7.
8.
PREBEN JENSEN 《Zoologica scripta》1978,7(1-4):159-173
The family Microlaimidae contains Bolbolaiminae subfam.n. (Bolbolaimus syn. Pseudomicro-laimus) and Microlaiminae ( Calomicrolaimus, Ixonema and Microlaimus ). The new family Molgolaimidae contains Aponematinae subfam.n. ( Aponema gen.n.) and Molgolaiminae subfam.n. ( Molgolaimus and Prodesmodora ). The main differentiating characters applied are: structures of the head region, shape of the oesophagus, position of the excretory pore, shape of the tail, structure of the gonads and ornamentation of the cuticle. The significance of porids and preanal supplements as distinguishing characters is, discussed. Microlaimidae are closely related to Desmodoridae; Molgolaimidae related to Spiriniidae. Paramicrolaimus is transferred from Microlaimidae to Spiriniidae.–Six species from the Øresund, Denmark, are redescribed: Microlaimus punctulatus Gerlach, 1950 and M. acinaces Warwick & Piatt, 1973; Aponema torosus (Lorenzen, 1973) gen.n., comb.n. (syn. Microlaimus torosus Loren-zen, 1973); Molgolaimus allgeni (Gerlach, 1950) comb.n. (syn. Microlaimus allgeni Gerlach, 1950) and M. turgofrons (Lorenzen, 1972) comb.n. (syn. Microlaimus turgofrons Lorenzen, 1972); Paramicrolaimus spirulifer Wieser, 1959. 相似文献
9.
MARIANNE PHILIPP LISE BACH HANSEN HENNING ADSERSEN HANS R. SIEGISMUND 《Botanical journal of the Linnean Society. Linnean Society of London》2004,146(2):171-180
Lecocarpus pinnatifidus is an endemic member of the Asteraceae occurring on only one island in the Galápagos archipelago. The capitula are large with female ray florets and male disc florets. They are self-compatible but this study suggests fruit set is pollen limited. Visits from Xylocopa darwini and other larger insect pollinators are rare, and small insects seem to be the main pollinators. Small insects carry few pollen grains and most likely mediate self-pollinations. Self-compatibility and seed set after selfing are the most common reproductive strategy in the Galápagos Islands and L. pinnatifidus seemingly fits well into this group. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 171–180. 相似文献
10.
Interactive effects of herbivory and sand burial on growth of a tropical dune plant, Ipomoea pes-caprae 总被引:1,自引:0,他引:1
CATHERINE BACH 《Ecological Entomology》1998,23(3):238-245
1. This study examined the effects of insect herbivory, sand burial, and the interactive effects of these factors, on the growth of beach morning glory, Ipomoea pes-caprae, a common tropical dune plant. Levels of herbivory and sand burial were manipulated on individual shoots, and effects on stem growth, leaf production, and production of adventitious roots and axillary branches by nodes were examined.
2. Sand burial had a significant positive effect on the production of roots, but did not affect growth in stem length or leaf production.
3. Effects of herbivory were consistently negative, and persisted for 6 weeks after the herbivore damage was incurred. Stem growth rates and leaf production decreased and the production of bare nodes (with no roots or branches) and mortality of apical meristems increased.
4. Interactive effects of herbivory and sand burial influenced both leaf production and root production. In the case of root production, the effects of herbivory in decreasing the proportion of nodes that produced roots occurred only in the presence of burial. In contrast, burial masked the negative effects of herbivory on leaf production. 相似文献
2. Sand burial had a significant positive effect on the production of roots, but did not affect growth in stem length or leaf production.
3. Effects of herbivory were consistently negative, and persisted for 6 weeks after the herbivore damage was incurred. Stem growth rates and leaf production decreased and the production of bare nodes (with no roots or branches) and mortality of apical meristems increased.
4. Interactive effects of herbivory and sand burial influenced both leaf production and root production. In the case of root production, the effects of herbivory in decreasing the proportion of nodes that produced roots occurred only in the presence of burial. In contrast, burial masked the negative effects of herbivory on leaf production. 相似文献