全文获取类型
收费全文 | 395篇 |
免费 | 5篇 |
国内免费 | 2篇 |
专业分类
化学 | 284篇 |
晶体学 | 7篇 |
力学 | 11篇 |
数学 | 13篇 |
物理学 | 87篇 |
出版年
2023年 | 1篇 |
2022年 | 5篇 |
2021年 | 16篇 |
2020年 | 12篇 |
2019年 | 9篇 |
2018年 | 7篇 |
2017年 | 6篇 |
2016年 | 11篇 |
2015年 | 11篇 |
2014年 | 8篇 |
2013年 | 20篇 |
2012年 | 20篇 |
2011年 | 27篇 |
2010年 | 18篇 |
2009年 | 13篇 |
2008年 | 23篇 |
2007年 | 19篇 |
2006年 | 15篇 |
2005年 | 18篇 |
2004年 | 15篇 |
2003年 | 23篇 |
2002年 | 21篇 |
2001年 | 9篇 |
2000年 | 9篇 |
1999年 | 4篇 |
1998年 | 3篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1973年 | 1篇 |
排序方式: 共有402条查询结果,搜索用时 15 毫秒
321.
Dario Braga Lucia Maini Fabrizia Grepioni 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》1998,110(16):2365-2366
322.
de la Torre Alexander F. Ali Akbar Galetto Fábio Z. Braga Antonio L. Delgado José A. C. Paixão Márcio W. 《Molecular diversity》2020,24(1):1-10
Molecular Diversity - A combined organocatalytic and multicomponent synthetic approach was designed for the preparation of selenium-based peptoids and peptide–peptoid conjugates. This... 相似文献
323.
324.
Prof. Maria L. S. O. Lima Dr. Carolyne B. Braga Dr. Tiago B. Becher Dr. Mikel Odriozola-Gimeno Dr. Miquel Torrent-Sucarrat Dr. Iván Rivilla Prof. Fernando P. Cossío Prof. Anita J. Marsaioli Prof. Catia Ornelas 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(20):6213-6222
Photodynamic therapy has been used to treat a variety of diseases, however, there is continuing search for new biocompatible photosensitizers. Herein, we demonstrate for the first time that imidazo[1,2-a]pyrimidine compounds are able to generate singlet oxygen species and can act as photosensitizers in the intracellular environment. Our results show that this class of compounds absorb and emit in the 400–500 nm region, present low cytotoxicity in the dark, are efficiently uptaken by cells, are fluorescent in intracellular medium, and generate singlet oxygen upon irradiation, killing cancer cells within 2 h at low concentration (2.0 μm ). The imidazo[1,2-a]pyrimidine compounds are a potential new tool for phototheranostics, because they can be simultaneously used for fluorescence imaging and photodynamic therapy. 相似文献
325.
Erika Takagi Nunes Adriane Araújo Braga Daniela Carvalho dos Santos Maria Izabel Camargo-Mathias 《Micron (Oxford, England : 1993)》2010,41(6):585-591
Among the decapods, the caridean Exhippolysmata oplophoroides has been described as a simultaneous protandric hermaphrodite, seeing that it presents a male initial stage followed by a hermaphrodite one in which it can function as male and as female. This work had the aims of characterizing the microscopical morphology of the male portion of the ovotestes gonads from E. oplophoroides, at the different development stages, identifying each cell from the germ lines during spermatogenesis, as well as describing the ultramorphology of spermatozoans in the terminal region of the vasa deferentia. Shrimps were collected in Ubatuba, north coast of São Paulo, and their male gonads and the ampoule were removed, fixed and processed according to histological routine and for scanning electron microscopy. The testicular portion is divided in lobes, inside which cells at the same stage of the spermatogenic cycle are observed, with prevalence of spermatogonia and spermatocytes at stages I, II and V of gonad development, whereas spermatids and spermatozoans are found at stages III and IV, respectively. Ultramorphology of the terminal portion of the vasa deferentia exhibits mature aflagellated spike-shaped spermatozoans, encased in secretion and between membrane foldings that will constitute the spermatophores. Despite presenting reproductive characteristics common to other decapods, E. oplophoroides shows spermatozoans as well as spermatophore with typical morphology, which is important for its identification and taxonomy. Further, this species showed polysaccharide secretions where the spermatozoa are immerse as far as the testicular portion, which could have a role in their transport and nutrition as well as spermatophore constitution and/or fixation; differently, other caridean species begin spermatophore formation during the passage of the gametes through the vasa deferentia. 相似文献
326.
Carlos J. Braga Barros Josiney A. Souza Victor H. L. Rocha 《Bulletin of the Brazilian Mathematical Society》2015,46(2):181-204
In this paper we develop a theory of Lyapunov stability for generalized flows on principal and associated bundles. We present a study of Lyapunov stability and attraction in the total space of a principal bundle by means of the action of the structure group.We also relate limit sets, prolongations, prolongational limit sets, attracting sets and stable sets in the total space of an associated bundle to the corresponding concepts in the fibers. 相似文献
327.
Braga Lilian R. Carvalho Thiago O. Nunes Alécio R. Araújo Kelly R. O. Prado Alexandre G. S. 《Journal of Thermal Analysis and Calorimetry》2017,130(3):1697-1706
Journal of Thermal Analysis and Calorimetry - Chitosan microspheres were used to remove emerging pollutants such as: oxycam anti-inflammatories, piroxycam, meloxycam and tenoxycam from water.... 相似文献
328.
Adriano H. Braga Pedro Vidinha Liane M. Rossi 《Current Opinion in Green and Sustainable Chemistry》2020
- Download : Download high-res image (366KB)
- Download : Download full-size image
329.
330.