全文获取类型
收费全文 | 2142篇 |
免费 | 106篇 |
出版年
2023年 | 6篇 |
2022年 | 10篇 |
2021年 | 38篇 |
2020年 | 14篇 |
2019年 | 25篇 |
2018年 | 35篇 |
2017年 | 30篇 |
2016年 | 42篇 |
2015年 | 73篇 |
2014年 | 69篇 |
2013年 | 153篇 |
2012年 | 148篇 |
2011年 | 151篇 |
2010年 | 93篇 |
2009年 | 93篇 |
2008年 | 153篇 |
2007年 | 172篇 |
2006年 | 142篇 |
2005年 | 115篇 |
2004年 | 169篇 |
2003年 | 127篇 |
2002年 | 117篇 |
2001年 | 27篇 |
2000年 | 20篇 |
1999年 | 21篇 |
1998年 | 29篇 |
1997年 | 21篇 |
1996年 | 12篇 |
1995年 | 16篇 |
1994年 | 10篇 |
1993年 | 12篇 |
1992年 | 14篇 |
1991年 | 19篇 |
1990年 | 9篇 |
1989年 | 10篇 |
1988年 | 12篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1970年 | 1篇 |
1967年 | 3篇 |
1965年 | 1篇 |
排序方式: 共有2248条查询结果,搜索用时 15 毫秒
71.
Sugiyama N Masuda T Shinoda K Nakamura A Tomita M Ishihama Y 《Molecular & cellular proteomics : MCP》2007,6(6):1103-1109
We developed novel methods for phosphopeptide enrichment using aliphatic hydroxy acid-modified metal oxide chromatography (MOC). Titania and zirconia were successfully applied to enrich phosphopeptides with the aid of aliphatic hydroxy acids, such as lactic acid and beta-hydroxypropanoic acid, to reduce the interaction between acidic non-phosphopeptides and the metal oxides. These methods removed the vast majority of non-phosphopeptides from phosphoprotein standard digests, and large numbers of phosphopeptides could be readily identified. The methods were coupled with nano-LC-MS/MS systems without difficulty. Recovery of phosphopeptides in MOC varied greatly from peptide to peptide, ranging from a few percent to 100%, and the average was almost 50%. Repeatability and linearity were satisfactory. In an examination of the cytoplasmic fraction of HeLa cells, more than 1000 phosphopeptides were identified using lactic acid-modified titania MOC and beta-hydroxypropanoic acid-modified zirconia MOC, respectively. The overlap between phosphopeptides enriched by these two methods was 40%, and the combined results provided 1646 unique phosphopeptides. To our knowledge, this is the first successful application of a single MOC-based approach to phosphopeptide enrichment from complex biological samples such as cell lysates. 相似文献
72.
王明强 罗阿蓉 周青松 陈婧婷 谢婷婷 李逸 Douglas Chesters 石晓宇 肖晖 刘桓吉 丁强 周璇 罗一平 路园园 佟一杰 赵政宇 白明 郭鹏飞 陈思翀 中村彰宏 彭艳琼 赵延会 魏淑花 林晓龙 陈华燕 罗世孝 陆宴辉 鲁亮 余建平 周欣 邹怡 路浩 朱朝东 《生物多样性》2022,30(10):22454-236
当前, 全球昆虫数量和多样性均处于下降趋势, 而导致这一趋势的原因主要包括人为干扰及气候变化。本文基于森林、草地、农业、水生和土壤生态系统, 以植食性、访花、捕食性、寄生性、食果以及食腐昆虫为重点功能昆虫群, 综述了近三十年来国内外昆虫多样性研究领域的主要进展, 并分析了发展趋势。近年来, 昆虫多样性的研究维度不断拓展, 形态多样性研究不断深入, 系统发生多样性、功能多样性和遗传多样性等研究也显著加强。此外, 昆虫多样性研究的空间尺度也逐步扩大, 大尺度区域性研究甚至全球范围的调查持续增长。昆虫进化历史也被引入多样性格局研究中, 并随着系统发生信息学方法的普及而被整合到生态系统建成和生物多样性形成机制研究中。未来需要加强关键昆虫类群整合分类学研究、功能性状多样性、林冠昆虫多样性、互作网络结构等方向的研究。 相似文献
73.
74.
75.
Akihiro Hirata Yoko Miyamoto Akihisa Kaneko Hiroki Sakai Kyoko Yoshizaki Tokuma Yanai Takako Miyabe‐Nishiwaki Juri Suzuki 《Journal of medical primatology》2019,48(2):137-140
Primary neuroendocrine neoplasm of the liver is extremely rare in both humans and non‐human primates. The present report describes the clinical and pathological findings of an aged Japanese macaque (Macaca fuscata) with hepatic neuroendocrine carcinoma. To our knowledge, this is the first report of hepatic neuroendocrine neoplasm in macaques. 相似文献
76.
Sakamoto Kazunori Ogiwara Natsuko Kaji Tomomitsu Sugimoto Yurie Ueno Mitsuru Sonoda Masatoshi Matsui Akihiro Ishida Junko Tanaka Maho Totoki Yasushi Shinozaki Kazuo Seki Motoaki 《Journal of plant research》2019,132(4):541-568
Journal of Plant Research - Soybean (Glycine max) roots establish associations with nodule-inducing rhizobia and arbuscular mycorrhizal (AM) fungi. Both rhizobia and AM fungi have been shown to... 相似文献
77.
Common marmosets vocalize phee calls as isolation calls, which seem to facilitate their reunion with family groups. To identify multiple acoustic properties with different time courses, we examined acoustic modulations of phees during different social contexts of isolation. Subject marmosets were totally isolated in one condition, were visually isolated and could exchange vocalizations in another condition, and were visually isolated and subsequently totally isolated in a third condition. We recorded 6,035 phees of 10 male–female marmoset pairs and conducted acoustic analysis. The marmosets frequently vocalized phees that were temporally elongated and louder during isolation, with varying time courses of these changes in acoustic parameters. The vocal rates and sound levels of the phees increased as soon as the marmosets saw their pair mates being taken away, and then gradually calmed down. The phee duration was longer in conditions during which there were no vocal responses from their pair mates. Louder vocalizations are conspicuous and seem to be effective for long‐distance transmission, whereas shorter call duration during vocal exchanges might avoid possible vocal overlap between mates. Am. J. Primatol. 72:681–688, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
78.
Akihiro Kondo John Sidney Scott Southwood Marie-France del Guercio Ettore Appella Hiroshi Sakamoto Howard M. Grey Esteban Celis Robert W. Chesnut Ralph T. Kubo A. Sette 《Immunogenetics》1997,45(4):249-258
Previous studies have defined two different peptide binding motifs specific for HLA-A
*
0101. These motifs are characterized by the presence of tyrosine (Y) at the C-termini of 9-mer and 10-mer peptides, and either
a small polar or hydrophobic (S, T, M) residue in position 2, or a negatively charged (D or E) residue in position 3. In this
study, the structural requirements for peptide binding to A
*
0101 have been further analyzed by examining the binding capacity of large sets of peptides corresponding to naturally occurring
sequences which bore one or the other of these two A
*
0101-specific motifs. By correlating the presence of specific residue types at each position along the peptide sequence with increased
(or decreased) binding affinity, the prominent influence of secondary anchor residues was revealed. In most cases, the two
anchors in positions 2 and 3 appear to act synergistically. With the exception of the DE3 submotif in 9-mer peptides, a positive role for aromatic residues in position 1 and the center of the peptide (positions
4 or 5 of 9- or 10-mer peptides, respectively), and proline at C-3, were also consistently detected. However, secondary anchor
residues also appear to differ significantly between the two different submotifs, demonstrating that A
*
0101 can utilize alternative modes in binding its peptide ligands. According to these analyses, specific refined submotifs were
also established, and their merit verified by independent sets of potential A
*
0101 binding peptides. Besides providing useful insight into the nature of the interaction of the A
*
0101 allele with its peptide ligands, such refined motifs should also facilitate accurate prediction of potential A
*
0101-restricted peptide epitopes.
Received: 16 July 1996 / Revised: 18 September 1996 相似文献
79.
80.