全文获取类型
收费全文 | 3292篇 |
免费 | 194篇 |
国内免费 | 4篇 |
出版年
2023年 | 9篇 |
2022年 | 10篇 |
2021年 | 50篇 |
2020年 | 46篇 |
2019年 | 68篇 |
2018年 | 110篇 |
2017年 | 70篇 |
2016年 | 140篇 |
2015年 | 193篇 |
2014年 | 218篇 |
2013年 | 242篇 |
2012年 | 303篇 |
2011年 | 275篇 |
2010年 | 190篇 |
2009年 | 183篇 |
2008年 | 218篇 |
2007年 | 190篇 |
2006年 | 136篇 |
2005年 | 141篇 |
2004年 | 113篇 |
2003年 | 109篇 |
2002年 | 84篇 |
2001年 | 72篇 |
2000年 | 83篇 |
1999年 | 55篇 |
1998年 | 17篇 |
1997年 | 17篇 |
1996年 | 11篇 |
1995年 | 12篇 |
1994年 | 5篇 |
1993年 | 9篇 |
1992年 | 13篇 |
1991年 | 15篇 |
1990年 | 16篇 |
1989年 | 14篇 |
1988年 | 7篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 8篇 |
1984年 | 2篇 |
1983年 | 7篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1978年 | 3篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1969年 | 3篇 |
排序方式: 共有3490条查询结果,搜索用时 31 毫秒
1.
Yuichi Mori Yoshitaka Miura Yutaka Oiso Seo Hisao Kozaki Takazumi 《Human genetics》1995,96(4):481-482
The human thyroxine-binding globulin (TBG) gene has been localized to X chromosome (Xq22.2) by in situ hybridization using a biotinylated gDNA probe. This is consistent with previous mapping of the TBG gene to chromosome Xq21-q22. 相似文献
2.
3.
4.
K. H. Jang J. W. Seo K. B. Song C. H. Kim S. K. Rhee 《Bioprocess and biosystems engineering》1999,21(5):453-458
Secretion of levansucrase from Zymomonas mobilis in Escherichiacoli by glycine supplement was investigated. A significant amount of levansucrase (about 25% of total activity) was found in intact whole-cells. Cell fractionation experiments showed that levansucrase was found both in the periplasmic space and in the cytoplasmic fraction of E. coli. None or only trace amounts of levansucrase was detected in the extracellular culture broth at 24 h of cultivation and it accrued with the increasing concentration of glycine in the culture medium and duration of the culture period. Optimal glycine concentration for the maximum secretion of levansucrase was in the range of 0.8-1%, in which approximately 20-50% of levansucrase was released into the extracellular fraction at 24 h of cultivation, although glycine retarded the bacterial growth. 相似文献
5.
Ha Na Seo Bo Young Jeon Hung Thuan Tran Dae Hee Ahn Doo Hyun Park 《Biotechnology and Bioprocess Engineering》2008,13(2):224-231
Saccharomyces sp. SK0704 (further defined as SK0704) isolated from long-term-ripening kimchi was identified by a biochemical method with
an API kit; its physiology was found to be very similar to that of S. cerevisiae ATCC 26603 (further defined as ATCC 26603), except in terms of starch utilization. SK0704 did not excrete extracellular glucoamylase,
but utilized starch as a sole carbon source under only aerobic conditions. Crude enzyme excreted from SK0704 catalyzed the
saccharification of starch to glucose, but ATCC 26603 did not. The PCR product obtained using the chromosomal DNA of SK0704
and the primers designed on the basis of the extracellular glucoamylase-coding gene of S. diastaticus was homologous with the intracellular sporulation-specific glucoamylase of S. cerevisiae. SDS-PAGE pattern of soluble protein extracted from yeast cells grown on glucose was greatly different from that on starch.
From these results, we proposed that the SK0704 may have a specific physiological function for starch catabolism such as membrane
transport system and intracellular sac-charification of starch. 相似文献
6.
7.
8.
Jae-Il Ahn In-Keun Jang Young-Kwon Seo Hee-Hoon Yoon Yeon-Ho Shin Jae-Chan Kim Kye-Yong Song Eun-Kyung Yang Jung-Keug Park 《Biotechnology and Bioprocess Engineering》2008,13(3):279-287
Herein, we reconstructed a rabbit corneal epithelium on a lyophilized amniotic membrane (LAM) using a modified version of
two Teflon rings (the Ahn’s supporter). We compared the corneal epithelial cells we had differentiated in vitro using air-liquid interface (6 days, 12 days) and submerged (6 days, 12 days) cultures and followed a six-day tilting dynamic
air-liquid interface culture with a six-day tilting submerged culture. We characterized the reconstructed corneal epithelium
using digital photography, histological imaging, and transmission electron microscopy. The reconstructed corneal epithelium
created under air-liquid interface culture exhibited a healthier basal corneal epithelial layer than that created under submerged
culture. The reconstructed corneal epithelium on the LAM that was produced using the tilting dymanic culture exhibited a healthy
basal layer. We therefore proposed that tilting submerged culture not only supplied nutrients from the medium to the corneal
epithelial cells on the LAM, but it also removed the horny layer in the upper part of the reconstructed corneal epithelium,
presumably by mimicking the effects of blinking. This study demonstrated that corneal epithelium reconstruction on a LAM using
a tilting submerged culture after a tilting air-liquid interface culture may be useful not only for allogeneic or autologous
transplantation, but also for in vitro toxicological test kits. 相似文献
9.
Jung-Min Shin Mi Yoon Kim Kyung-Cheol Sohn So-Young Jung Hae-Eul Lee Jae Woo Lim Sooil Kim Young-Ho Lee Myung Im Young-Joon Seo Chang Deok Kim Jeung-Hoon Lee Young Lee Tae-Jin Yoon 《PloS one》2014,9(4)
Nrf2 plays a role in protection of cells against oxidative stress and xenobiotic damage by regulating cytoprotective genes. In this study, we investigated the effect of Nrf2 on melanogenesis in normal human melanocytes (NHMCs). When NHMCs were transduced with a recombinant adenovirus expressing Nrf2, melanin synthesis was significantly decreased. Consistent with this result, overexpression of Nrf2 decreased the expression of tyrosinase and tyrosinase-related protein 1. The inhibitory effect of Nrf2 was reversed by overexpression of Keap1, an intracellular regulator of Nrf2. Interestingly, Nrf2 overexpression resulted in marked activation of PI3K/Akt signaling. Conversely, inhibition of PI3K activity by treatment with wortmannin reversed the depigmentary effects of Nrf2. Taken together, these results strongly suggest that Nrf2 negatively regulates melanogenesis by modulating the PI3K/Akt signaling pathway. 相似文献
10.
Tokiha Masuda-Ozawa Trish Hoang Yeon-Soo Seo Lin-Feng Chen Maria Spies 《Nucleic acids research》2013,41(6):3576-3587
DNA repair helicases function in the cell to separate DNA duplexes or remodel nucleoprotein complexes. These functions are influenced by sensing and signaling; the cellular pool of a DNA helicase may contain subpopulations of enzymes carrying different post-translational modifications and performing distinct biochemical functions. Here, we report a novel experimental strategy, single-molecule sorting, which overcomes difficulties associated with comprehensive analysis of heterologously modified pool of proteins. This methodology was applied to visualize human DNA helicase F-box–containing DNA helicase (FBH1) acting on the DNA structures resembling a stalled or collapsed replication fork and its interactions with RAD51 nucleoprotein filament. Individual helicase molecules isolated from human cells with their native post-translational modifications were analyzed using total internal reflection fluorescence microscopy. Separation of the activity trajectories originated from ubiquitylated and non-ubiquitylated FBH1 molecules revealed that ubiquitylation affects FBH1 interaction with the RAD51 nucleoprotein filament, but not its translocase and helicase activities. 相似文献