全文获取类型
收费全文 | 1976篇 |
免费 | 182篇 |
国内免费 | 1篇 |
出版年
2023年 | 3篇 |
2022年 | 4篇 |
2021年 | 38篇 |
2020年 | 30篇 |
2019年 | 41篇 |
2018年 | 69篇 |
2017年 | 53篇 |
2016年 | 92篇 |
2015年 | 120篇 |
2014年 | 133篇 |
2013年 | 173篇 |
2012年 | 167篇 |
2011年 | 181篇 |
2010年 | 121篇 |
2009年 | 112篇 |
2008年 | 137篇 |
2007年 | 122篇 |
2006年 | 103篇 |
2005年 | 113篇 |
2004年 | 71篇 |
2003年 | 62篇 |
2002年 | 51篇 |
2001年 | 32篇 |
2000年 | 14篇 |
1999年 | 18篇 |
1998年 | 14篇 |
1997年 | 8篇 |
1996年 | 8篇 |
1995年 | 8篇 |
1994年 | 2篇 |
1993年 | 5篇 |
1992年 | 6篇 |
1991年 | 2篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1984年 | 4篇 |
1982年 | 2篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1968年 | 3篇 |
1967年 | 1篇 |
1965年 | 3篇 |
1962年 | 1篇 |
1961年 | 1篇 |
1960年 | 2篇 |
1959年 | 1篇 |
排序方式: 共有2159条查询结果,搜索用时 15 毫秒
121.
Young Rae Ji Hei Jung Kim Dong Hun Yu Ki Beom Bae Seo Jin Park Si Jun Park Woo Young Jang Min-Cheol Kang Jain Jeong Yong Hun Sung Minjee Choi Taejun Park Taesun Park Jong Won Yun Hyun-Shik Lee Sanggyu Lee Myoung Ok Kim Zae Young Ryoo 《Biochemical and biophysical research communications》2014
Chronic hepatitis is a major cause of liver cancer, so earlier treatment of hepatitis might be reducing liver cancer incidence. Hepatitis can be induced in mice by treatment with Concanavalin A (Con A); the resulting liver injury causes significant CD4+ T cell activation and infiltration. In these T cells, Roquin, a ring-type E3 ubiquitin ligase, is activated. To investigate the role of Roquin, we examined Con A-induced liver injury and T cell infiltration in transgenic (Tg) mice overexpressing Roquin specifically in T cells. In Roquin Tg mice, Con A treatment caused greater increases in both the levels of liver injury enzymes and liver tissue apoptosis, as revealed by TUNEL and H&E staining, than wild type (WT) mice. Further, Roquin Tg mice respond to Con A treatment with greater increases in the T cell population, particularly Th17 cells, though Treg cell counts are lower. Roquin overexpression also enhances increases in pro-inflammatory cytokines, including IFN-γ, TNF-α and IL-6, upon liver injury. Furthermore, Roquin regulates the immune response and apoptosis in Con A induced hepatitis via STATs, Bax and Bcl2. These findings suggest that over-expression of Roquin exacerbates T-cell mediated hepatitis. 相似文献
122.
Jang-Seu Ki Dae-Sik Hwang Tae-Jin Park Sang-Hoon Han Jae-Seong Lee 《Molecular biology reports》2010,37(4):1943-1955
Otter populations are declining throughout the world and most otter species are considered endangered. Molecular methods are
suitable tools for population genetic research on endangered species. In the present study, we analyzed the complete mitochondrial
genome (mitogenome) sequence of the Eurasian otter Lutra lutra. The mitochondrial DNA sequence of the Eurasian otter is 16,505 bp in length and consists of 13 protein-coding genes, 22
tRNAs, 2 rRNAs, and a control region (CR). The CR sequence of otters from Europe and Asia showed nearly identical numbers
and nucleotide sequences of minisatellites. Phylogenetic analysis of Mustelidae mitogenomes, including individual genes, revealed
that Lutrinae and Mustelinae form a clade, and that L. lutra and Enhydra lutris are sister taxa within the Lutrinae. Phylogenetic analyses revealed that of the 13 mitochondrial protein-coding genes, ND5
is the most reliable marker for analysis of phylogenetic relationships within the Mustelidae. 相似文献
123.
124.
125.
Ki Yong Lee Young Woong Cho Junghyun Park Dong Young Lee Seung Hyun Kim Young Choong Kim Sang Hyun Sung 《Phytochemical analysis : PCA》2010,21(4):314-321
Introduction – Pulsatilla koreana Nakai, with triterpenoidal saponins as its main pharmacological effective compounds, is known to have several biological activities, including hypoglycaemic, antitumour, cognition‐enhancing, neuroprotective, cytotoxic and antiangiogenic activities. However, few analytical methods have been reported on the quality assessment of P. koreana roots. Obejective – To establish a high‐performance liquid chromatography coupled with evaporative light scattering detection for the simultaneous determination of five triterpenoidal saponins, including pulsatilloside E (1), pulsatilla saponin H (2), anemoside B4 (3), hederacolchiside E (4) and cussosaponin C (5) in P. koreana. Methodology – The chromatographic separation was performed on a Shiseido CapCell PAK C18 analytical column efficiently using gradient elution with acetonitrile and water. Results – All calibration curves showed excellent linear regressions (R2 > 0.9996) within the range of tested concentrations. The intra‐ and inter‐day variations were below 4.78% in terms of RSD. The recoveries were 94.82–102.97% with RSD of 0.27–3.92% for spiked P. koreana samples. Conclusion – The validated method was successfully used for the analysis of five saponins in P. koreana from different locations. Moreover, the different samples were clustered in accordance with contents of triterpenoidal saponins based on aglycon type by a principal component analysis. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
126.
Eun-Jin Kim Hyung Won Ryu Marcus J. Curtis-Long Jaehee Han Jun Young Kim Jung Keun Cho Dawon Kang Ki Hun Park 《Bioorganic & medicinal chemistry letters》2010,20(14):4237-4239
Although it has not been extensively studied, a significant volume of literature suggests that TREK2 will probably turn out to be an important channel in charge of tuning neuronal transmitter and hormone levels. Thus, pharmacological tools which can manipulate this channel, such as selective agonists are essential both in drug design and to further our understanding of this system. Our investigations have shown that sulfonate (‘O’) chalcone and sulfonamide (‘N’) chalcones regulate the TREK2 channel in remarkably different ways: sulfonamide chalcone 5 behaved as an inhibitor with an IC50 of 62 μM, whereas the sulfonate analogue 11 activated TREK2 with EC50 value of 167 μM. 相似文献
127.
Thommey P. Thomas Seok Ki Choi Ming-Hsin Li Alina Kotlyar James R. Baker 《Bioorganic & medicinal chemistry letters》2010,20(17):5191-5194
This communication describes the synthesis and in vitro biological evaluation of novel generation 5 PAMAM dendrimers conjugated with riboflavin as a targeting ligand. Cell-based experiments demonstrated that a dendrimer conjugated with riboflavin is able to undergo cellular binding and uptake in KB cells, and when the dendrimer is also conjugated with methotrexate, the riboflavin dendrimer conjugate can potently inhibit cell growth. 相似文献
128.
Young Bae Ryu Jang Hoon Kim Su-Jin Park Jong Sun Chang Mun-Chual Rho Ki-Hwan Bae Ki Hun Park Woo Song Lee 《Bioorganic & medicinal chemistry letters》2010,20(3):971-974
We isolated 18 polyphenols with neuraminidase inhibitory activity from methanol extracts of the roots of Glycyrrhiza uralensis. These polyphenols consisted of four chalcones (1–4), nine flavonoids (5–13), four coumarins (14–17), and one phenylbenzofuran (18). When we tested the effects of these individual compounds and analogs thereof on neuraminidase activation, we found that isoliquiritigenin (1, IC50 = 9.0 μM) and glycyrol (14, IC50 = 3.1 μM) had strong inhibitory activity. Structure–activity analysis showed that the furan rings of the polyphenols were essential for neuraminidase inhibitory activity, and that this activity was enhanced by the apioside group on the chalcone and flavanone backbone. In addition, the presence of a five-membered ring between C-4 and C-2′ in coumestan was critical for neuraminidase inhibition. All neuraminidase inhibitors screened were found to be reversible noncompetitive inhibitors. 相似文献
129.
Bon‐A Cho Nam‐Hyuk Cho Chan‐Ki Min Se‐Yoon Kim Jae‐Seong Yang Jung Rok Lee Jin Woo Jung Won‐Chul Lee Kijeong Kim Mi‐Kyung Lee Sanguk Kim Kwang Pyo Kim Seung‐Yong Seong Myung‐Sik Choi Ik‐Sang Kim 《Proteomics》2010,10(8):1699-1715
Orientia tsutsugamushi, an obligate intracellular bacterium, is the causative agent of Scrub typhus. The control mechanisms for bacterial gene expression are largely unknown. Here, the global gene expression of O. tsutsugamushi within eukaryotic cells was examined using a microarray and proteomic approaches for the first time. These approaches identified 643 genes, corresponding to approximately 30% of the genes encoded in the genome. The majority of expressed genes belonged to several functional categories including protein translation, protein processing/secretion, and replication/repair. We also searched the conserved sequence blocks (CSBs) in the O. tsutsugamushi genome which is unique in that up to 40% of its genome consists of dispersed repeated sequences. Although extensive shuffling of genomic sequences was observed between two different strains, 204 CSBs, covering 48% of the genome, were identified. When combining the data of CSBs and global gene expression, the CSBs correlates well with the location of expressed genes, suggesting the functional conservation between gene expression and genomic location. Finally, we compared the gene expression of the bacteria‐infected fibroblasts and macrophages using microarray analysis. Some major changes were the downregulation of genes involved in translation, protein processing and secretion, which correlated with the reduction in bacterial translation rates and growth within macrophages. 相似文献
130.
Marie Yeo Young Mi Na Dong Kyu Kim Young Bae Kim Hee Jeong Wang Jung A. Lee Jae Youn Cheong Kwang Jae Lee Young‐Ki Paik Sung Won Cho 《Proteomics》2010,10(2):266-276
Biomarkers for the detection of early hepatocellular carcinoma (HCC) are urgently needed. To identify biomarkers of HCC, we performed a comparative proteomics analysis, based on 2‐DE of HCC tissues and surrounding non‐tumor tissues. Six xenobiotic enzymes were significantly down‐regulated in the HCC tissue. Among these, phenol sulfotransferase (SULT1A1) was confirmed by Western blot analysis in 105 HCC patients. SULT1A1 showed a significant decrease in 98.1% of the HCC tissues, with 88.6% sensitivity and 66.7% specificity for the detection of HCC. Immunohistochemistry for SULT1A1 was performed and compared with glypican‐3, which is a well‐known marker of HCC. The results showed down‐regulation of SULT1A1 and up‐regulation of glypican‐3 in 52.6 and 71.9% of the HCCs, and the use of both markers improved the sensitivity up to 78.9%. Moreover, SULT1A1 was useful in differentiating early HCC from benign dysplastic nodules. Clinically, the down‐regulation of SULT1A1 was closely associated with an advanced International Union Against Cancer stage and high levels of serum α‐fetoprotein. In conclusion, the results of this study demonstrate that the loss of SULT1A1 appears to be a characteristic molecular signature of HCC. SULT1A1 might be a useful biomarker for the detection of early HCC and help predict the clinical outcome of patients with HCC. 相似文献