全文获取类型
收费全文 | 2994篇 |
免费 | 184篇 |
国内免费 | 5篇 |
出版年
2024年 | 8篇 |
2023年 | 39篇 |
2022年 | 95篇 |
2021年 | 150篇 |
2020年 | 91篇 |
2019年 | 120篇 |
2018年 | 153篇 |
2017年 | 97篇 |
2016年 | 127篇 |
2015年 | 130篇 |
2014年 | 147篇 |
2013年 | 258篇 |
2012年 | 215篇 |
2011年 | 206篇 |
2010年 | 127篇 |
2009年 | 101篇 |
2008年 | 129篇 |
2007年 | 121篇 |
2006年 | 97篇 |
2005年 | 94篇 |
2004年 | 98篇 |
2003年 | 86篇 |
2002年 | 66篇 |
2001年 | 24篇 |
2000年 | 23篇 |
1999年 | 25篇 |
1998年 | 15篇 |
1997年 | 12篇 |
1996年 | 23篇 |
1995年 | 8篇 |
1994年 | 19篇 |
1993年 | 14篇 |
1992年 | 16篇 |
1991年 | 8篇 |
1990年 | 19篇 |
1988年 | 15篇 |
1987年 | 17篇 |
1986年 | 15篇 |
1985年 | 16篇 |
1984年 | 16篇 |
1983年 | 9篇 |
1982年 | 9篇 |
1980年 | 10篇 |
1979年 | 12篇 |
1977年 | 13篇 |
1976年 | 7篇 |
1973年 | 9篇 |
1971年 | 8篇 |
1970年 | 7篇 |
1969年 | 9篇 |
排序方式: 共有3183条查询结果,搜索用时 31 毫秒
81.
Farsenyl pyrophosphate synthase is a potential molecular drug target of risedronate in Babesia bovis
Akio Ueno Mohamad Alaa Terkawi Miki Yokoyama Shinuo Cao Gabriel Aboge Mahmoud Aboulaila Yoshifumi Nishikawa Xuenan Xuan Naoaki Yokoyama Ikuo Igarashi 《Parasitology international》2013,62(2):189-192
A cDNA encoding farnesyl pyrophosphate synthase of Babesia bovis (BbFPPS) has been isolated, cloned and characterized as molecular drug target. Sequence analysis revealed that BbFPPS contains an open reading frame of 1011 bp with predicted 336 amino acids and molecular mass of 38 kDa. Antiserum raised in mice against recombinant BbFPPS expressed in Escherichia coli specifically reacted with native protein of B. bovis parasites by Western blot analysis and indirect immunofluorescent test. Enzymatic assay using recombinant BbFPPS revealed that the Km value of the enzyme for isopentenyl pyrophosphate and dimethylallyl pyrophosphate was 2.494 ± 1.536 μM. Risedronate inhibited the activity of BbFPPS yielding IC50 value of 8.4 ± 1.2 nM. Furthermore, the in vitro growth of B. bovis was significantly inhibited in the presence of a micromolar concentration of risedronate (IC50 = 4.02 ± 0.91 μM). No regrowth of B. bovis was observed at 10 μM of risedronate in the subsequent viability test. These results demonstrate that BbFPPS is the molecular target of risedronate, which could inhibit the in vitro growth of B. bovis. 相似文献
82.
A new fungal endophyte, Scolecobasidium humicola, was identified as a common dark septate endophytic fungal (DSE) species under both natural and agricultural conditions. This fungus was found to grow endophylically in the roots of tomato seedlings. Light microscopy of cross-sections of colonized tomato roots showed that the intercellular, pigmented hyphae of the fungus were mostly limited to the epidermal layer and formed outer mantle-like structures. Two isolates of S. humicola, H2-2 and F1-3, have shown the ability to increase plant biomass with an organic nitrogen source. This finding is the first report of S. humicola as an endophyte and could help to improve plant growth with organic nitrogen sources. 相似文献
83.
Mahmoud EIHefnawi Bangli Soliman Nourhan Abu-Shahba Marwa Amer 《基因组蛋白质组与生物信息学报(英文版)》2013,11(6):354-367
We aimed to shed new light on the roles of microRNAs (miRNAs) in liver cancer using an integrative in silico bioinformatics analysis. A new protocol for target prediction and functional analysis is presented and applied to the 26 highly differentially deregulated miRNAs in hepatocellular carcinoma. This framework comprises: (1) the overlap of prediction results by four out of five target prediction tools, including TargetScan, PicTar, miRanda, DIANA-microT and miRDB (combining machine-learning, alignment, interaction energy and statistical tests in order to minimize false positives), (2) evidence from previous microarray analysis on the expression of these targets, (3) gene ontology (GO) and pathway enrichment analysis of the miRNA targets and their pathways and (4) linking these results to oncogenesis and cancer hallmarks. This yielded new insights into the roles of miRNAs in cancer hallmarks. Here we presented several key targets and hundreds of new targets that are significantly enriched in many new cancer-related hallmarks. In addition, we also revealed some known and new oncogenic pathways for liver cancer. These included the famous MAPK, TGFβ and cell cycle pathways. New insights were also provided into Wnt signaling, prostate cancer, axon guidance and oocyte meiosis pathways. These signaling and developmental pathways crosstalk to regulate stem cell transformation and implicate a role of miRNAs in hepatic stem cell deregulation and cancer development. By analyzing their complete interactome, we proposed new categorization for some of these miRNAs as either tumor-suppressors or oncomiRs with dual roles. Therefore some of these miRNAs may be addressed as therapeutic targets or used as therapeutic agents. Such dual roles thus expand the view of miRNAs as active maintainers of cellular homeostasis. 相似文献
84.
85.
Mohammad Azam Ismail Warad Saud I. Al‐Resayes M. Rafiq Siddiqui M. Oves 《化学与生物多样性》2013,10(6):1109-1119
A new series of PdII complexes derived from thiosemicarbazone has been synthesized. The synthesized PdII complexes have been characterized on the basis of elemental analyses, FT‐IR, 1H‐ and 13C‐NMR, UV/VIS, and thermal studies. A square‐planar geometry has been assigned around PdII ions on the basis of results obtained from UV/VIS studies. The thiosemicarbazone ligand and its PdII complexes have been screened against Gram‐positive (Bacillus subtilis and Staphylococcus aureus) and Gram‐negative (Escherichia coli and Pseudomonas aeruginosa) bacteria in vitro as growth‐inhibiting agents, and the results revealed significant antibacterial activities. 相似文献
86.
Silvia Maioli Ann B?vner Zeina Ali Maura Heverin Muhammad-Al-Mustafa Ismail Elena Puerta Maria Olin Ahmed Saeed Marjan Shafaati Paolo Parini Angel Cedazo-Minguez Ingemar Bj?rkhem 《PloS one》2013,8(7)
We previously described a heterozygous mouse model overexpressing human HA-tagged 24S-hydroxylase (CYP46A1) utilizing a ubiquitous expression vector. In this study, we generated homozygotes of these mice with circulating levels of 24OH 30–60% higher than the heterozygotes. Female homozygous CYP46A1 transgenic mice, aged 15 months, showed an improvement in spatial memory in the Morris water maze test as compared to the wild type mice. The levels of N-Methyl-D-Aspartate receptor 1, phosphorylated-N-Methyl-D-Aspartate receptor 2A, postsynaptic density 95, synapsin-1 and synapthophysin were significantly increased in the hippocampus of the CYP46A1 transgenic mice as compared to the controls. The levels of lanosterol in the brain of the CYP46A1 transgenic mice were significantly increased, consistent with a higher synthesis of cholesterol. Our results are discussed in relation to the hypothesis that the flux in the mevalonate pathway in the brain is of importance in cognitive functions. 相似文献
87.
88.
Mohammadi Ali Akbar Zarei Ahmad Esmaeilzadeh Marjan Taghavi Mahmoud Yousefi Mahmood Yousefi Zahra Sedighi Fatemeh Javan Safoura 《Biological trace element research》2020,195(1):343-352
Biological Trace Element Research - Heavy metal pollution of soils in industrial zones continues to attract attention because of its potential human health risks. The present research is an attempt... 相似文献
89.
Najafzadeh Mohammad Javad Dolatabadi Somayeh de Hoog Sybren Esfahani Mahmoud Karimizadeh Haghani Iman Aghili Seyed Reza Ghazvini Roshanak Daei Rezaei-Matehkolaei Ali Abastabar Mahdi Al-Hatmi Abdullah M. S. 《Mycopathologia》2020,185(3):515-525
Mycopathologia - Fungi of the genus Fusarium are well known as major plant pathogens but also cause a broad spectrum of human infections. Sixty-three clinical isolates, collected during... 相似文献