全文获取类型
收费全文 | 578篇 |
免费 | 30篇 |
出版年
2023年 | 2篇 |
2022年 | 6篇 |
2021年 | 11篇 |
2020年 | 9篇 |
2019年 | 11篇 |
2018年 | 11篇 |
2017年 | 18篇 |
2016年 | 17篇 |
2015年 | 29篇 |
2014年 | 30篇 |
2013年 | 35篇 |
2012年 | 52篇 |
2011年 | 46篇 |
2010年 | 19篇 |
2009年 | 27篇 |
2008年 | 42篇 |
2007年 | 33篇 |
2006年 | 29篇 |
2005年 | 21篇 |
2004年 | 20篇 |
2003年 | 18篇 |
2002年 | 22篇 |
2001年 | 6篇 |
2000年 | 9篇 |
1999年 | 7篇 |
1998年 | 5篇 |
1997年 | 4篇 |
1996年 | 2篇 |
1994年 | 5篇 |
1993年 | 6篇 |
1992年 | 4篇 |
1991年 | 6篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1987年 | 3篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1979年 | 2篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1970年 | 1篇 |
1969年 | 4篇 |
1967年 | 3篇 |
1966年 | 1篇 |
1962年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有608条查询结果,搜索用时 15 毫秒
91.
Emiliano Manzo Paola Bartolommei Filippo DellAgnello Roberto Cozzolino 《Ecology and evolution》2022,12(6)
Evidence of abnormal coloration in wild animals provides useful information to better understand its adaptive function and its impact on survival. For this reason, we need to know the frequency and distribution of these abnormal phenotypes in wild populations. Here, we report two records of hypopigmentation in European pine marten Martes martes, obtained during a camera‐trapping survey on Elba Island, Central Italy. We do not know what has caused anomalous coloration of pine marten on Elba Island, but it is possible that the inbreeding may have played a role in this isolated population. Although the light coloration certainly entails an increased visibility of pine martens, it is possible that the low predator pressure and the absence of other wild carnivore populations in our study could mitigate the mortality risk due to the light phenotype. The increased use of camera traps across the world can potentially facilitate the discovery of cases of anomalous colorations in wild populations, providing an unprecedented insight into the occurrence of this phenomenon in wild mammal species. 相似文献
92.
93.
94.
95.
Enrico Casalone Carmine Di Ilio Giorgio Federici Mario Polsinelli 《Antonie van Leeuwenhoek》1988,54(4):367-375
Total glutathione content, glutathione peroxidase, glutathione transferase and glutathione reductase activities have been measured in 12 species of yeasts. All the strains tested contained glutathione, though in different amounts, as well as the above mentioned enzymes. To discriminate between the selenium-dependent and the selenium-independent form, glutathione peroxidase activity has been measured with both H2O2 and cumene hydroperoxide. Rhodotorula glutinis appeared to be the only strain in which the selenium-dependent form was not found, but this yeast exhibited the highest level of selenium-independent glutathione peroxidase activity as compared to the other strains. 相似文献
96.
97.
David A. Schaer Richard P. Beckmann Jack A. Dempsey Lysiane Huber Amelie Forest Nelusha Amaladas Yanxia Li Ying Cindy Wang Erik R. Rasmussen Darin Chin Andrew Capen Carmine Carpenito Kirk A. Staschke Linda A. Chung Lacey M. Litchfield Farhana F. Merzoug Xueqian Gong Philip W. Iversen Michael Kalos 《Cell reports》2018,22(11):2978-2994
98.
A putative natural hybrid betweenOrchis laxiflora andO. morio (Orchidaceae) from southern Italy, formerly known asO. alata, was characterized both on morphological and molecular grounds in order to confirm its hybrid status and to trace its maternal lineage. The morphological characters of the putative hybrid showed intermediacy between those of the parent species, and restriction fragment length polymorphism (RFLP) analysis of a region of the nuclear ribosomal DNA confirmed its hybrid origin. Chloroplast DNA RFLP analysis indicated thatO. morio provided the maternal genome. 相似文献
99.
Habitat preference and flowering‐time variation contribute to reproductive isolation between diploid and autotetraploid Anacamptis pyramidalis
下载免费PDF全文
![点击此处可从《Journal of evolutionary biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
L. Pegoraro D. Cafasso R. Rinaldi S. Cozzolino G. Scopece 《Journal of evolutionary biology》2016,29(10):2070-2082
Tetraploid lineages are typically reproductively isolated from their diploid ancestors by post‐zygotic isolation via triploid sterility. Nevertheless, polyploids often also exhibit ecological divergence that could contribute to reproductive isolation from diploid ancestors. In this study, we disentangled the contribution of different forms of reproductive isolation between sympatric diploid and autotetraploid individuals of the food‐deceptive orchid Anacamptis pyramidalis by quantifying the strength of seven reproductive barriers: three prepollination, one post‐pollination prezygotic and three post‐zygotic. The overall reproductive isolation between the two cytotypes was found very high, with a preponderant contribution of two prepollination barriers, that is phenological and microhabitat differences. Although the contribution of post‐zygotic isolation (triploid sterility) is confirmed in our study, these results highlight that prepollination isolation, not necessarily involving pollinator preference, can represent a strong component of reproductive isolation between different cytotypes. Thus, in the context of polyploidy as quantum speciation, that generates reproductive isolation via triploid sterility, ecological divergence can strengthen the reproductive isolation between cytotypes, reducing the waste of gametes in low fitness interploidy crosses and thus favouring the initial establishment of the polyploid lineage. Under this light, speciation by polyploidy involves ecological processes and should not be strictly considered as a nonecological form of speciation. 相似文献
100.
Francesca Wanda Rossi Nella Prevete Felice Rivellese Antonio Lobasso Filomena Napolitano Francescopaolo Granata Carmine Selleri Amato de Paulis 《Clinical and molecular allergy : CMA》2016,14(1):15