全文获取类型
收费全文 | 3190篇 |
免费 | 178篇 |
专业分类
3368篇 |
出版年
2023年 | 13篇 |
2022年 | 48篇 |
2021年 | 52篇 |
2020年 | 29篇 |
2019年 | 61篇 |
2018年 | 85篇 |
2017年 | 71篇 |
2016年 | 86篇 |
2015年 | 143篇 |
2014年 | 160篇 |
2013年 | 265篇 |
2012年 | 246篇 |
2011年 | 254篇 |
2010年 | 158篇 |
2009年 | 142篇 |
2008年 | 215篇 |
2007年 | 168篇 |
2006年 | 178篇 |
2005年 | 148篇 |
2004年 | 144篇 |
2003年 | 122篇 |
2002年 | 104篇 |
2001年 | 28篇 |
2000年 | 34篇 |
1999年 | 21篇 |
1998年 | 24篇 |
1997年 | 20篇 |
1996年 | 19篇 |
1995年 | 13篇 |
1994年 | 14篇 |
1993年 | 17篇 |
1992年 | 25篇 |
1991年 | 20篇 |
1990年 | 32篇 |
1989年 | 19篇 |
1988年 | 27篇 |
1987年 | 14篇 |
1986年 | 12篇 |
1985年 | 16篇 |
1984年 | 13篇 |
1983年 | 14篇 |
1982年 | 6篇 |
1981年 | 5篇 |
1979年 | 8篇 |
1975年 | 7篇 |
1974年 | 9篇 |
1973年 | 7篇 |
1972年 | 7篇 |
1971年 | 6篇 |
1970年 | 13篇 |
排序方式: 共有3368条查询结果,搜索用时 15 毫秒
81.
Kenji Mori Masanao Matsui Yusuke Sumiki 《Bioscience, biotechnology, and biochemistry》2013,77(3):205-222
In order to clarify the structure of ring A of gibberellins, thirteen lactones of cyclohexan series, of which eight were new, were prepared to examine their infrared spectra. So far; the experiment is concerned, γ-lactones show the characteristic absorption band in the rang 1775~1782 cm?1 in dioxane, while 5-ones in the range 1730/~1762 cm?1. Since the absorptio band due to lactone carbonyl of gibberellins occurs at the range 1777~1786 cm?1 in dioxane, the lactone ring of gibberellins seems to be γ. 相似文献
82.
83.
84.
Atsushi Higashi Junji Morita Hiroshi Sakai Tohru Komano 《Bioscience, biotechnology, and biochemistry》2013,77(10):2093-2094
The fluorescent antibody technique was used to trace an inoculated Nocardia erythropolis strain which was capable of rapidly degrading phthalate esters in soil column and activated sludge systems. The reaction of antibody to Nocardia erythropolis S-1 was highly strain specific, i. e., only one of twelve other strain of N. erythropolis was stained with this fluorescent antibody. All other species of Nocardia and other genera of bacteria and a strain of Candida were not stained. Using this technique it was demonstrated that N. erythropolis S-1 inoculated into activated sludge and soil column systems was successfully distinguished from many other microorganisms in mixed culture systems, and the distribution of this strain was appreciated. 相似文献
85.
86.
Yusuke Tani Keisuke Araki Takehiro Nagai Kowa Koida Shigeki Nakauchi Michiteru Kitazaki 《PloS one》2013,8(1)
It has been argued that when an observer moves, a contingent retinal-image motion of a stimulus would strengthen the perceived glossiness. This would be attributed to the veridical perception of three-dimensional structure by motion parallax. However, it has not been investigated whether the effect of motion parallax is more than that of retinal-image motion of the stimulus. Using a magnitude estimation method, we examine in this paper whether cross-modal coordination of the stimulus change and the observer''s motion (i.e., motion parallax) is essential or the retinal-image motion alone is sufficient for enhancing the perceived glossiness. Our data show that a retinal-image motion simulating motion parallax without head motion strengthened the perceived glossiness but that its effect was weaker than that of motion parallax with head motion. These results suggest the existence of an additional effect of the cross-modal coordination between vision and proprioception on glossiness perception. That is, motion parallax enhances the perception of glossiness, in addition to retinal-image motions of specular surfaces. 相似文献
87.
Supranee Phanthanawiboon Kriengsak Limkittikul Yusuke Sakai Nobuyuki Takakura Masayuki Saijo Takeshi Kurosu 《PloS one》2016,11(2)
Severe dengue is caused by host responses to viral infection, but the pathogenesis remains unknown. This is, in part, due to the lack of suitable animal models. Here, we report a non-mouse-adapted low-passage DENV-3 clinical isolate, DV3P12/08, derived from recently infected patients. DV3P12/08 caused a lethal systemic infection in type I and II IFN receptor KO mice (IFN-α/β/γR KO mice), which have the C57/BL6 background. Infection with DV3P12/08 induced a cytokine storm, resulting in severe vascular leakage (mainly in the liver, kidney and intestine) and organ damage, leading to extensive hemorrhage and rapid death. DV3P12/08 infection triggered the release of large amounts of TNF-α, IL-6, and MCP-1. Treatment with a neutralizing anti-TNF-α antibody (Ab) extended survival and reduced liver damage without affecting virus production. Anti-IL-6 neutralizing Ab partly prolonged mouse survival. The anti-TNF-α Ab suppressed IL-6, MCP-1, and IFN-γ levels, suggesting that the severe response to infection was triggered by TNF-α. High levels of TNF-α mRNA were expressed in the liver and kidneys, but not in the small intestine, of infected mice. Conversely, high levels of IL-6 mRNA were expressed in the intestine. Importantly, treatment with Angiopoietin-1, which is known to stabilize blood vessels, prolonged the survival of DV3P12/08-infected mice. Taken together, the results suggest that an increased level of TNF-α together with concomitant upregulation of Tie2/Angiopoietin signaling have critical roles in severe dengue infection. 相似文献
88.
89.
Yuki Takayasu Yusuke Ogura Ryo Towada 《Bioscience, biotechnology, and biochemistry》2016,80(8):1459-1463
The first synthesis of the (9R,13R)-stereoisomer of LDS1, a flower-inducing oxylipin isolated from Lemna paucicostata, has been achieved from a known allylic alcohol by a seven-step sequence that involves the Horner–Wadsworth–Emmons olefination to construct its full carbon framework and an enzymatic hydrolysis of a penultimate methyl ester intermediate to provide the target molecule. 相似文献
90.
Yusuke Maeda Rintaro Iwata Hara Kazutaka Nishina Kie Yoshida-Tanaka Taiichi Sakamoto Takanori Yokota 《Nucleosides, nucleotides & nucleic acids》2019,38(5):338-348
Properties of cationic peptides bearing amino or guanidino groups with various side chain lengths that bind to double stranded RNAs (dsRNAs) were investigated. Peptides with shorter side chain lengths effectively bound to dsRNAs (12mers) increasing their thermal stability. NMR measurements suggested that the cationic peptide binds to the inner side of the major groove of dsRNA. These peptides also increased the thermal stability of siRNA and effectively protected from RNase A digestion. On the other hand, both peptides containing amino groups and guanidine groups did not disturb RNAi activity. 相似文献