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991.
Takefumi Uemura Masaya Yamamoto Ai Kametaka Yu-shin Sou Atsuko Yabashi Akane Yamada Hiromichi Annoh Satoshi Kametaka Masaaki Komatsu Satoshi Waguri 《Molecular and cellular biology》2014,34(9):1695-1706
Recent findings have suggested that the autophagic isolation membrane (IM) might originate from a domain of the endoplasmic reticulum (ER) called the omegasome. However, the morphological relationships between ER, omegasome, and IM remain unclear. In the present study, we found that hybrid structures composed of a double FYVE domain-containing protein 1 (DFCP1)-positive omegasome and the IM accumulated in Atg3-deficient mouse embryonic fibroblasts (MEFs). Moreover, correlative light and electron microscopy and immunoelectron microscopy revealed that green fluorescent protein (GFP)-tagged DFCP1 was localized on tubular or vesicular elements adjacent to the IM rims. Through detailed morphological analyses, including optimization of a fixation method and electron tomography, we observed a cluster of thin tubular structures between the IM edges and ER, part of which were continuous with IM and/or ER. The formation of these thin tubular clusters was observed in several cell lines and MEFs deficient for Atg5, Atg7, or Atg16L1 but not in FIP200-deficient cells, suggesting that they were relevant to the earlier events in autophagosome formation. Taken together, our findings indicate that these tubular profiles represent a part of the omegasome that links the ER with the IM. 相似文献
992.
Zhiwei Chen Dazhi SuLuoyan Ai Xiaoke JiangChangwei Wu Qingqing XuXiaohan Wang Zhuping Fan 《Gene》2014
Backgrounds and Aims
UDP-glucuronosyltransferase 1 A1 (UGT1A1) is an enzyme that transforms small lipophilic molecules into water-soluble and excretable metabolites. UGT1A1 polymorphisms contribute to hyperbilirubinemia. This study quantitatively associated UGT1A1 variants in patients with hyperbilirubinemia and healthy subjects.Methods
A total of 104 individuals with hyperbilirubinemia and 105 healthy controls were enrolled for genotyping and DNA sequencing UGT1A1 sequence variants, including the Phenobarbital Response enhancer module (PBREM) region, the promoter region (TATA box), and the 5 exons for quantitative association with hyperbilirubinemia.Results
Eleven UGT1A1 variants were revealed in the case and control subjects, four of which were novel coding variants. A variant of PBREM (UGT1A1*60) was found in 47.6% of the patients, a TA repeat motif in the 5-primer promoter region [A(TA)7TAA,UGT1A1*28] was found in 27.9% of the patients, and p.G71R (UGT1A1*6) was in 33.2% of the patients. For the healthy controls, the frequency of UGT1A1*60, UGT1A1*28 and UGT1A1*6 was 26.7%, 9.0% and 15.7%, respectively. Homozygous UGT1A1*28 and homozygous UGT1A1*6 were significantly associated with the risk of adult hyperbilirubinemia, with an odds ratio (OR) of 17.79 (95% CIs, 2.11–133.61) and 14.93 (95% CIs, 1.83–121.88), respectively. Quantitative analysis showed that sense mutation (including UGT1A1*6) and UGT1A1*28/*28, but not UGT1A1*60/*60 or UGT1A1*1/*28, was associated with increased serum total bilirubin (TB) levels. High linkage disequilibrium occurred between UGT1A1*60 and UGT1A1*28 (D′ = 0.964, r2 = 0.345).Conclusions
This study identified four novel UGT1A1 coding variants, some of which were associated with increased serum TB levels. A quantitative approach to evaluate adult hyperbilirubinemia provides a more vigorous framework for better understanding of adult hyperbilirubinemia genetics. 相似文献993.
Key message
Arabidopsis Ca 2+ -ATPase ACA8 plays a role in sucrose signalling during early seedling development by integrating developmental signals with carbon source availability.Abstract
Calcium (Ca2+) is an essential signal transduction element in eukaryotic organisms. Changes in the levels of intracellular Ca2+ affect multiple developmental processes in plants, including cell division, polar growth, and organogenesis. Here, we report that the plasma-membrane-localised Arabidopsis Ca2+-ATPase ACA8 plays a role in sucrose signalling during early seedling development. Disruption of the ACA8 gene elevated the expression of genes that encode transporters for Ca2+ efflux. The seedlings that carried a T-DNA insertion mutation in ACA8 experienced water stress during early development. This response was unrelated to inadequate osmoregulatory responses and was most likely caused by disruption of cell membrane integrity and severe ion leakage. In addition, aca8-1 seedlings displayed a significant decline in photosynthetic performance and arrested root growth after removal of sucrose from the growth medium. The two phenomena resulted from impaired photosynthesis, reduced cell proliferation in the root meristem and the sucrose control of cell-cycle events. All of the stress-response phenotypes were rescued when expression of ACA8 was restored in aca8-1 mutant. Taken together, our results indicate that ACA8-mediated Ca2+ signalling contributes to modulate early seedling development and coordinates root development with nutrient availability. 相似文献994.
995.
996.
Yan Ping Chen Jeffery S. Pettis Miguel Corona Wei Ping Chen Cong Jun Li Marla Spivak P. Kirk Visscher Gloria DeGrandi-Hoffman Humberto Boncristiani Yan Zhao Dennis vanEngelsdorp Keith Delaplane Leellen Solter Francis Drummond Matthew Kramer W. Ian Lipkin Gustavo Palacios Michele C. Hamilton Barton Smith Shao Kang Huang Huo Qing Zheng Ji Lian Li Xuan Zhang Ai Fen Zhou Li You Wu Ji Zhong Zhou Myeong-L. Lee Erica W. Teixeira Zhi Guo Li Jay D. Evans 《PLoS pathogens》2014,10(7)
997.
Background
The Tibetan pig is one of domestic animals indigenous to the Qinghai-Tibet Plateau. Several geographically isolated pig populations are distributed throughout the Plateau. It remained an open question if these populations have experienced different demographic histories and have evolved independent adaptive loci for the harsh environment of the Plateau. To address these questions, we herein investigated ~ 40,000 genetic variants across the pig genome in a broad panel of 678 individuals from 5 Tibetan geographic populations and 34 lowland breeds.Results
Using a series of population genetic analyses, we show that Tibetan pig populations have marked genetic differentiations. Tibetan pigs appear to be 3 independent populations corresponding to the Tibetan, Gansu and Sichuan & Yunnan locations. Each population is more genetically similar to its geographic neighbors than to any of the other Tibetan populations. By applying a locus-specific branch length test, we identified both population-specific and -shared candidate genes under selection in Tibetan pigs. These genes, such as PLA2G12A, RGCC, C9ORF3, GRIN2B, GRID1 and EPAS1, are involved in high-altitude physiology including angiogenesis, pulmonary hypertension, oxygen intake, defense response and erythropoiesis. A majority of these genes have not been implicated in previous studies of highlanders and high-altitude animals.Conclusion
Tibetan pig populations have experienced substantial genetic differentiation. Historically, Tibetan pigs likely had admixture with neighboring lowland breeds. During the long history of colonization in the Plateau, Tibetan pigs have developed a complex biological adaptation mechanism that could be different from that of Tibetans and other animals. Different Tibetan pig populations appear to have both distinct and convergent adaptive loci for the harsh environment of the Plateau.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-834) contains supplementary material, which is available to authorized users. 相似文献998.
Xin‐Yuan Sun Liang‐Wu Lin Guang‐Yao Liu Xin‐Gen Liu Ai‐Jin Wu Shi‐Ming Huang 《Luminescence》2014,29(2):132-137
Red‐emitting Li2Sr1‐3x/2EuxSiO4 0≤x≤0.5) phosphors were synthesized at 900°C in air by a solid‐state reaction. The synthesized phosphors were characterized by X‐ray powder diffraction, photoluminescence (PL) excitation (PLE) and PL spectra. The results from the PLE spectra suggest that the strong 394 nm excitation peak associated with the 5L6 state of Eu3+ ions is of significance for near ultraviolet pumped white light‐emitting diodes and solid‐state lighting. It is also noted that the position of the charge transfer state of Eu3+ ions shifts towards the higher energy side (blue shift) by increasing the content of Eu3+ ions. The predominant emissions of Eu3+ ions under 394 nm excitation are observed at 580, 593, 614, 656 and 708 nm, which are attributed to the 5D0 → 7FJ (J = 0, 1, 2, 3 and 4), respectively. The PL results reveal that the optimal content of the red‐emitting Li2Sr1‐3x/2EuxSiO4 phosphors is x = 0.475. Simulation of the white light excited by 394 nm near ultraviolet light has also been carried out for its potential white light‐emitting diode applications. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
999.
Yiping Wang Xiaojian Zhang Qing Liu Chenbing Ai Hongyu Mo Jia Zeng 《Current microbiology》2009,59(1):35-41
The thioredoxin system consists of thioredoxin (Trx), thioredoxin reductase (TrxR) and NADPH, which plays several key roles
in maintaining the redox environment of the cell. In Acidithiobacillus ferrooxidans, thioredoxin system may play important functions in the activity regulation of periplasmic proteins and energy metabolism.
Here, we cloned thioredoxin (trx) and thioredoxin reductase (trxR) genes from Acidithiobacillus ferrooxidans, and expressed the genes in Escherichia coli. His-Trx and His-TrxR were purified to homogeneity with one-step Ni-NTA affinity column chromatography. Site-directed mutagenesis
results confirmed that Cys33, Cys36 of thioredoxin, and Cys142, Cys145 of thioredoxin reductase were active-site residues. 相似文献
1000.
Huaiyang?Zhou Jiangtao?LiEmail author Xiaotong?Peng Jun?Meng Fengping?Wang Yuncan?Ai 《Journal of microbiology (Seoul, Korea)》2009,47(3):235-247
Submarine hydrothermal vents are among the least-understood habitats on Earth but have been the intense focus of research
in the past 30 years. An active hydrothermal sulfide chimney collected from the Dudley site in the Main Endeavour vent Field
(MEF) of Juan de Fuca Ridge was investigated using mineralogical and molecular approaches. Mineral analysis indicated that
the chimney was composed mainly of Fe-, Zn-and Cu-rich sulfides. According to phylogenetic analysis, within the Crenarchaeota,
clones of the order Desulfurococcales predominated, comprising nearly 50% of archaeal clones. Euryarchaeota were composed mainly of clones belonging to Thermococcales and deep-sea hydrothermal vent Euryarchaeota (DHVE), each of which accounted for about 20% of all clones. Thermophilic or hyperthermophilic physiologies were common to
the predominant archaeal groups. More than half of bacterial clones belonged to ɛ-Proteobacteria, which confirmed their prevalence in hydrothermal vent environments. Clones of Proteobacteria (γ-, δ-, β-), Cytophaga-Flavobacterium-Bacteroides (CFB) and Deinococcus-Thermus occurred as well. It was remarkable that methanogens
and methanotrophs were not detected in our 16S rRNA gene library. Our results indicated that sulfur-related metabolism, which
included sulfur-reducing activity carried out by thermophilic archaea and sulfur-oxidizing by mesophilic bacteria, was common
and crucial to the vent ecosystem in Dudley hydrothermal site. 相似文献