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81.
Human isolated gingival fibromatosis is an oral disorder characterized by a slowly progressive benign enlargement of gingival
tissues. The most common genetic form, hereditary gingival fibromatosis (HGF), is usually transmitted as an autosomal dominant
trait. We report here for the first time a newly identified maternally inherited gingival fibromatosis in two unrelated Chinese
families and mapped this disease locus to human chromosome 11p15 with a maximum two point LOD score of 8.70 at D11S4046 (θ = 0) for family 1 and of 6.02 at D11S1318 for family 2. Haplotype analysis placed the critical region in the interval defined by D11S1984 and D11S1338. A cluster of maternally expressed genes is within this critical region. We screened individuals in these two families for
mutations for all known maternally expressed genes within this region. None was found either within the coding sequence or
at the intron–exon boundary of these genes. Neither did we detect any loss of imprinting in three informative imprinted genes
including H19, KCNQ1 downstream neighbor (KCNQ1DN) and cyclin-dependent kinase inhibitor 1C (CDKN1C). However, gene expression profile analysis revealed reduced expression of hemoglobin beta (HBB), hemoglobin delta (HBD), hemoglobin gamma A (HBG1) and hemoglobin gamma G (HBG2) genes at disease locus in HGF patients. This study suggests that genome imprinting might affect the development of HGF.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.
Conflict Of Interest Statement: No competing financial interests. 相似文献
82.
Yong Liang De-Yun Zhang Shuhong Ouyang Jingzhong Xie Qiuhong Wu Zhenzhong Wang Yu Cui Ping Lu Dong Zhang Zi-Ji Liu Jie Zhu Yong-Xing Chen Yan Zhang Ming-Cheng Luo Jan Dvorak Naxin Huo Qixin Sun Yong-Qiang Gu Zhiyong Liu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2015,128(8):1617-1629
83.
84.
Shijie He Chenglin Liu Xiaojun Li Shaopeng Ma Bo Huo Baohua Ji 《Biophysical journal》2015,108(3):489-497
Mechanical properties of cell membranes are known to be significantly influenced by the underlying cortical cytoskeleton. The technique of pulling membrane tethers from cells is one of the most effective ways of studying the membrane mechanics and the membrane-cortex interaction. In this article, we show that axon membranes make an interesting system to explore as they exhibit both free membrane-like behavior where the tether-membrane junction is movable on the surface of the axons (unlike many other cell membranes) as well as cell-like behavior where there are transient and spontaneous eruptions in the tether force that vanish when F-actin is depolymerized. We analyze the passive and spontaneous responses of axonal membrane tethers and propose theoretical models to explain the observed behavior. 相似文献
85.
Jianfeng Li Shuqing Zhang Shangli Shi Pinghui Huo 《World journal of microbiology & biotechnology》2011,27(6):1481-1489
Nitrogen (N) fixing Klebsiella pneumoniae RSN19 has high inorganic phosphorus (P) solubilizing capability, but its N2-fixing capability is limited. In order to acquire a P-solubilizing mutant strain with high efficiency N-fixing capability,
different microwave irradiation intensities and durations were tested on RSN19 in an attempt to produce mutants with improved
N2-fixation and P-solubilization capabilities. The effect of microwave irradiation power and time were studied and the microwave
mutagenesis parameters were optimized. Nitrogenase activity was tested on the mutant strains by acetylene reduction method;
and their P-solubilizing capability and genetic stability were determined. The results indicated that the best conditions
for microwave mutagenesis that produced better performed mutant strains were 250W, 36 s. Under these conditions a maximum
positive mutation rate of 1.66% was obtained, resulting in five genetically stable strains with promoted nitrogenase activity
which was designated as RSM-219, RSM-206, RSM-224, RSM-225 and RSM-275. Subculture tests showed that RSM-219 and RSM-206 were
genetically stable mutant strains with higher nitrogenase activity and phosphate solubilizing capabilities than the original
strain. Both RSM-219 and RSM-206 performed better than the original strain under N-free conditions when supplied with calcium
phosphate only, and produced greater increases in the biomass of alfalfa seedlings. 相似文献
86.
Huo A Zhang H Guan Y Zeng G Chen Y Li X 《Bioorganic & medicinal chemistry letters》2011,21(21):6242-6244
Stable and orally bio-available pro-drugs of CPS11 were synthesized. They are active on human umbilical vein endothelial cell proliferation assay and tube formation assay. The therapeutic efficacy and safety of 4 as a single agent or combined with Taxol in the treatment of MX-1 human breast cancer xenograft were evaluated. Compound 4 as a single agent failed to produce an anti-tumor activity, while it significantly enhanced antitumor potency of Taxol. 相似文献
87.
88.
Huang N Lian JF Huo JH Liu LY Ni L Yang X Zhou JQ Li ZF Song TS Huang C 《Cell biology international》2011,35(3):193-199
EGFP (enhanced green fluorescent protein) tagged to either the N (amino)-terminus [EGFP/hERG (human ether-a-go-go-related gene)] or C (carboxyl)-terminus (hERG/EGFP) of hERG channel is used to study mutant channel protein trafficking for several years. However, it has been reported that the process can alter hERG channel properties. The aim of the study was to determine whether EGFP tagged to N-terminus of hERG channels would alter the cellular localizations and the electrophysiological properties of hERG channels compared with untagged hERG channels. The hERG channels tagged with or without EGFP were transiently expressed in HEK (human embryonic kidney) 293 cells using a lipofectamine method. HEK 293 cells expressing pCDNA3-hERG or pEGFP-hERG were double immunolabelled with anti-hERG and anti-calnexin (an ER marker protein) followed with FITC- and TRITC (tetramethylrhodamine β-isothiocyanate)-labelled secondary antibodies, respectively. Confocal laser scanning microscope was used to observe the cellular localization of EGFP-tagged hERG channels and untagged hERG channels. Patch-clamp technique was used to record whole cell currents. We found that the EGFP/hERG fusion protein and untagged hERG channels were both expressed not only on the cell surface membrane but also in the cytoplasm of HEK293 cells. The EGFP/hERG appeared to influence the hERG channel gating properties, including reduction of the peak tail current density, more rapid inactivation process, faster recovery from inactivation and faster deactivation kinetics compared with untagged hERG channels. Our results suggest that the EGFP/hERG channel alter the electrophysiological properties of hERG channel, but it does not seem to alter the cellular location of hERG channels. Thus, EGFP tagging to N-terminus might be used for research of subcellular location of hERG channels but not for the channel electrophysiological properties. 相似文献
89.
Huo X Qi X Tang F Zu R Li L Wu B Qin Y Ji H Fu J Wang S Tian H Hu Z Yang H Zhou M Wang H Zhu F 《PloS one》2011,6(3):e17995
Background
We investigated the seropositive rates and persistence of antibody against pandemic (H1N1) 2009 virus (pH1N1) in pregnant women and voluntary blood donors after the second wave of the pandemic in Nanjing, China.Methodology/Principal Findings
Serum samples of unvaccinated pregnant women (n = 720) and voluntary blood donors (n = 320) were collected after the second wave of 2009 pandemic in Nanjing. All samples were tested against pH1N1 strain (A/California/7/2009) with hemagglutination inhibition assay. A significant decline in seropositive rates, from above 50% to about 20%, was observed in pregnant women and voluntary blood donors fifteen weeks after the second wave of the pandemic. A quarter of the samples were tested against a seasonal H1N1 strain (A/Brisbane/59/2007). The antibody titers against pH1N1 strain were found to correlate positively with those against seasonal H1N1 strain. The correlation was modest but statistically significant.Conclusions and Significance
The high seropositive rates in both pregnant women and voluntary blood donors suggested that the pH1N1 virus had widely spread in these two populations. Immunity derived from natural infection seemed not to be persistent well. 相似文献90.
Jiu-ru Zhao Yong-dong Li Li-min Pan Na Zhu Hong-xia Ni Guo-zhang Xu Yong-zhong Jiang Xi-xiang Huo Jun-qiang Xu Han Xia Na Han Shuang Tang Zhong Zhang Zheng Kou Simon Rayner Tian-xian Li 《中国病毒学》2011,26(6):418-427
A total of 100 HIN1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang,Hubei and Guangdong between June and November 2009,were provided by local CDC laboratories.After MDCK cell culture,57 Influenza A Pandemic (H1N1) viruses were isolated and submitted for whole genome sequencing.A total of 39 HA sequences,52 NA sequences,36 PB2 sequences,31 PB1 sequences,40 PA sequences,48 NP sequences,51 MP sequences and 36 NS sequences were obtained,including 20 whole genome sequences.Sequence comparison revealed they shared a high degree of homology (96%~99%) with known epidemic strains (A/Califomia/04/2009(H1N1).Phylogenetic analysis showed that although the sequences were highly conserved,they clustered into a small number of groups with only a few distinct strains.Site analysis revealed three substitutions at loop 220 (221-228) of the HA receptor binding site in the 39 HA sequences:A/Hubei/86/2009 PKVRDQEG→PKVRDQEA,A/Zhejiang/08/2009 PKVRDQEG→PKVRDQER,A/Hubei/75/2009PKVRDQEG→PKVRDQGG,the A/Hubei/75/2009 was isolated from an acute case,while the other two were from patients with mild symptoms.Other key sites such as 119,274,292 and 294 amino acids of NA protein,627 of PB2 protein were conserved.Meanwhile,all the M2 protein sequences possessed the Ser32Asn mutation,suggesting that these viruses were resistant to adamantanes.Comparison of these sequences with other H1N1 viruses collected from the NCBI database provides insight into H1N1 transmission and circulation patterns. 相似文献