全文获取类型
收费全文 | 371篇 |
免费 | 11篇 |
出版年
2023年 | 1篇 |
2022年 | 6篇 |
2021年 | 5篇 |
2020年 | 10篇 |
2019年 | 4篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2016年 | 9篇 |
2015年 | 14篇 |
2014年 | 16篇 |
2013年 | 31篇 |
2012年 | 53篇 |
2011年 | 62篇 |
2010年 | 35篇 |
2009年 | 2篇 |
2008年 | 14篇 |
2007年 | 13篇 |
2006年 | 15篇 |
2005年 | 10篇 |
2004年 | 7篇 |
2003年 | 8篇 |
2002年 | 15篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 4篇 |
1997年 | 6篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 5篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1977年 | 2篇 |
1976年 | 1篇 |
排序方式: 共有382条查询结果,搜索用时 281 毫秒
81.
82.
Del Rio TG Chertkov O Yasawong M Lucas S Deshpande S Cheng JF Detter C Tapia R Han C Goodwin L Pitluck S Liolios K Ivanova N Mavromatis K Pati A Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Rohde M Pukall R Sikorski J Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Lapidus A 《Standards in genomic sciences》2010,3(3):294-303
Intrasporangium calvum Kalakoutskii et al. 1967 is the type species of the genus Intrasporangium, which belongs to the actinobacterial family Intrasporangiaceae. The species is a Gram-positive bacterium that forms a branching mycelium, which tends to break into irregular fragments. The mycelium of this strain may bear intercalary vesicles but does not contain spores. The strain described in this study is an airborne organism that was isolated from a school dining room in 1967. One particularly interesting feature of I. calvum is that the type of its menaquinone is different from all other representatives of the family Intrasporangiaceae. This is the first completed genome sequence from a member of the genus Intrasporangium and also the first sequence from the family Intrasporangiaceae. The 4,024,382 bp long genome with its 3,653 protein-coding and 57 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
83.
Sikorski J Lapidus A Chertkov O Lucas S Copeland A Glavina Del Rio T Nolan M Tice H Cheng JF Han C Brambilla E Pitluck S Liolios K Ivanova N Mavromatis K Mikhailova N Pati A Bruce D Detter C Tapia R Goodwin L Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Rohde M Göker M Spring S Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP 《Standards in genomic sciences》2010,2(1):57-65
Veillonella parvula (Veillon and Zuber 1898) Prévot 1933 is the type species of the genus Veillonella in the family Veillonellaceae within the order Clostridiales. The species V. parvula is of interest because it is frequently isolated from dental plaque in the human oral cavity and can cause opportunistic infections. The species is strictly anaerobic and grows as small cocci which usually occur in pairs. Veillonellae are characterized by their unusual metabolism which is centered on the activity of the enzyme methylmalonyl-CoA decarboxylase. Strain Te3(T), the type strain of the species, was isolated from the human intestinal tract. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of a member of the large clostridial family Veillonellaceae, and the 2,132,142 bp long single replicon genome with its 1,859 protein-coding and 61 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
84.
Sun H Spring S Lapidus A Davenport K Del Rio TG Tice H Nolan M Copeland A Cheng JF Lucas S Tapia R Goodwin L Pitluck S Ivanova N Pagani I Mavromatis K Ovchinnikova G Pati A Chen A Palaniappan K Hauser L Chang YJ Jeffries CD Detter JC Han C Rohde M Brambilla E Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Land M 《Standards in genomic sciences》2010,3(3):276-284
Desulfarculus baarsii (Widdel 1981) Kuever et al. 2006 is the type and only species of the genus Desulfarculus, which represents the family Desulfarculaceae and the order Desulfarculales. This species is a mesophilic sulfate-reducing bacterium with the capability to oxidize acetate and fatty acids of up to 18 carbon atoms completely to CO(2). The acetyl-CoA/CODH (Wood-Ljungdahl) pathway is used by this species for the complete oxidation of carbon sources and autotrophic growth on formate. The type strain 2st14(T) was isolated from a ditch sediment collected near the University of Konstanz, Germany. This is the first completed genome sequence of a member of the order Desulfarculales. The 3,655,731 bp long single replicon genome with its 3,303 protein-coding and 52 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
85.
Ecosystem respiration and organic carbon processing in a large,tidally influenced river: the Hudson River 总被引:1,自引:0,他引:1
We estimated whole-ecosystem rates of respiration over a 40-km stretch of the tidally influenced freshwater Hudson River every 2 to 3 weeks from May through November. We measured in situ concentrations of oxygen over depth at dusk and dawn at 10 stations spaced over this interval. The use of multiple stations allowed for the consideration of the influence of tidal advection of water masses. Respiration was estimated from the decrease in oxygen overnight with a correction for diffusive exchange of oxygen with the atmosphere. We estimated this flux of oxygen to or from the atmosphere using the measured oxygen gradient and a transfer velocity model which is a function of wind velocity.Integration of the data for the period of May through November yields an estimate of whole-ecosystem respiration of 591 g C m–2 (S.E. = 66). That the standard error of this estimate is relatively low (11% of the estimate) indicates that the use of multiple stations adequately deals with error introduced through the advection of water between stations. The logarithm of average daily respiration rate was correlated with average daily temperature (p = 0.007;r
2 = 0.62). We used this temperature-respiration relationship to derive an estimate of the annual respiration rate of 755 g C m–2 yr–1 (S.E. = 72). This estimate is moderately sensitive to the estimated flux of oxygen between the atmosphere and water; using the lower and upper 95% confidence limits of our model relating the transfer velocity of oxygen to wind speed gives a range of annual respiration estimates from 665 g C m–2 yr–1 to 984 g C m–2 yr–1.The river is strongly heterotrophic, with most respiration driven by allochthonous inputs of organic matter from terrestrial ecosystems. The majority of the allochthonous inputs to the river (over 60%) are apparently metabolized within the river. Any change in allochthonous inputs due to changes in land use or climate patterns would be expected to alter the oxygen dynamics and energy flow within this tidally influenced river. 相似文献
86.
Gruwel Marco L.H.; Kuzio Bozena; Deslauriers Roxanne; Kupriyanov Valerie V. 《American journal of physiology. Cell physiology》1999,276(1):C193
The rubidium efflux from hypothermic rat hearts perfused by theLangendorff method at 20°C was studied. At thistemperature 87Rb-NMR efflux experiments showed theexistence of two 87Rb pools: cytoplasmic and mitochondrial.Rat heart mitochondria showed a very slow exchange of mitochondrialRb+ for cytoplasmic K+. After washout ofcytosolic Rb+, mitochondria kept a stable Rb+level for >30 min. Rb+ efflux from mitochondria wasstimulated with 0.1 mM 2,4-dinitrophenol (DNP), by sarcolemmalpermeabilization and concomitant cellular energy depletion by saponin(0.01 mg/ml for 4 min) in the presence of a perfusate mimickingintracellular conditions, or by ATP-sensitive K (KATP)channel openers. DNP, a mitochondrial uncoupler, caused the onset ofmitochondrial Rb+ exchange; however, the washout was notcomplete (80 vs. 56% in control). Energy deprivation by saponin, whichpermeabilizes the sarcolemma, resulted in a rapid and completeRb+ efflux. The mitochondrial Rb+ efflux rateconstant (k) decreased in the presence of glibenclamide, aKATP channel inhibitor (5 µM;k = 0.204 ± 0.065 min1; n = 8),or in the presence of ATP plus phosphocreatine (1.0 and 5.0 mM,respectively; k = 0.134 ± 0.021 min1;n = 4) in the saponin experiments (saponin only;k = 0.321 ± 0.079 min1; n = 3),indicating the inhibition of mitochondrial KATP channels. Thus hypothermia in combination with 87Rb-NMR allowed theprobing of the mitochondrial K+ pool in whole heartswithout mitochondrial isolation. 相似文献
87.
Marchler-Bauer A Anderson JB DeWeese-Scott C Fedorova ND Geer LY He S Hurwitz DI Jackson JD Jacobs AR Lanczycki CJ Liebert CA Liu C Madej T Marchler GH Mazumder R Nikolskaya AN Panchenko AR Rao BS Shoemaker BA Simonyan V Song JS Thiessen PA Vasudevan S Wang Y Yamashita RA Yin JJ Bryant SH 《Nucleic acids research》2003,31(1):383-387
The Conserved Domain Database (CDD) is now indexed as a separate database within the Entrez system and linked to other Entrez databases such as MEDLINE(R). This allows users to search for domain types by name, for example, or to view the domain architecture of any protein in Entrez's sequence database. CDD can be accessed on the WorldWideWeb at http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=cdd. Users may also employ the CD-Search service to identify conserved domains in new sequences, at http://www.ncbi.nlm.nih.gov/Structure/cdd/wrpsb.cgi. CD-Search results, and pre-computed links from Entrez's protein database, are calculated using the RPS-BLAST algorithm and Position Specific Score Matrices (PSSMs) derived from CDD alignments. CD-Searches are also run by default for protein-protein queries submitted to BLAST(R) at http://www.ncbi.nlm.nih.gov/BLAST. CDD mirrors the publicly available domain alignment collections SMART and PFAM, and now also contains alignment models curated at NCBI. Structure information is used to identify the core substructure likely to be present in all family members, and to produce sequence alignments consistent with structure conservation. This alignment model allows NCBI curators to annotate 'columns' corresponding to functional sites conserved among family members. 相似文献
88.
Grenier JM Wang L Manji GA Huang WJ Al-Garawi A Kelly R Carlson A Merriam S Lora JM Briskin M DiStefano PS Bertin J 《FEBS letters》2002,530(1-3):73-78
PYRIN-containing Apaf-1-like proteins (PYPAFs) are a recently identified family of proteins thought to function in apoptotic and inflammatory signaling pathways. PYPAF1 and PYPAF7 proteins have been found to assemble with the PYRIN–CARD protein ASC and coordinate the activation of NF-κB and pro-caspase-1. To determine if other PYPAF family members function in pro-inflammatory signaling pathways, we screened five other PYPAF proteins (PYPAF2, PYPAF3, PYPAF4, PYPAF5 and PYPAF6) for their ability to activate NF-κB and pro-caspase-1. Co-expression of PYPAF5 with ASC results in a synergistic activation of NF-κB and the recruitment of PYPAF5 to punctate structures in the cytoplasm. The expression of PYPAF5 is highly restricted to granulocytes and T-cells, indicating a role for this protein in inflammatory signaling. In contrast, PYPAF2, PYPAF3, PYPAF4 and PYPAF6 failed to colocalize with ASC and activate NF-κB. PYPAF5 also synergistically activated caspase-1-dependent cytokine processing when co-expressed with ASC. These findings suggest that PYPAF5 functions in immune cells to coordinate the transduction of pro-inflammatory signals to the activation of NF-κB and pro-caspase-1. 相似文献
89.
Marco L.H. Gruwel Bozena Kuzio Roxanne Deslauriers Valerie V. Kupriyanov 《Cryobiology》1998,37(4):355-361
The effect of hypothermia on isolated perfused rat hearts was studied with31P NMR. Hearts were continuously perfused with phosphate-free Krebs–Henseleit buffer while the perfusate temperature was adjusted. Perfusate pH was kept at 7.40 ± 0.02 throughout the experiments. Using the chemical shift difference between PCr and Pithe intracellular pH was estimated. At 36, 20, and 10°C a cytosolic alkalinization at a pH of 7.05 ± 0.04, 7.21 ± 0.05, and 7.40 ± 0.03 was observed, respectively. At 10°C two Piresonances were observed with a separation of 0.25 ppm. This resonance corresponded to a Piresonance of a cellular compartment with a local pH of 7.78 ± 0.06, likely mitochondrial. This additional resonance disappeared upon warming of the hearts back to 36°C. 相似文献
90.
Functions of intermediate filaments in neuronal development and disease 总被引:21,自引:0,他引:21
Five major types of intermediate filament (IF) proteins are expressed in mature neurons: the three neurofilament proteins (NF-L, NF-M, and NF-H), alpha-internexin, and peripherin. While the differential expression of IF genes during embryonic development suggests potential functions of these proteins in axogenesis, none of the IF gene knockout experiments in mice caused gross developmental defects of the nervous system. Yet, deficiencies in neuronal IF proteins are not completely innocuous. Substantial developmental loss of motor axons was detected in mice lacking NF-L and in double knockout NF-M;NF-H mice, supporting the view of a role for IFs in axon stabilization. Moreover, the absence of peripherin resulted in approximately 30% loss of small sensory axons. Mice lacking NF-L had a scarcity of IF structures and exhibited a severe axonal hypotrophy, causing up to 50% reduction in conduction velocity, a feature that would be very detrimental for large animal species. Unexpectedly, the NF-M rather than NF-H protein turned out to be required for proper radial growth of large myelinated axons. Studies with transgenic mice suggest that some types of IF accumulations, reminiscent of those found in amyotrophic lateral sclerosis (ALS), can have deleterious effects and even cause neurodegeneration. Additional evidence for the involvement of IFs in pathogenesis came from the recent discovery of neurofilament gene mutations linked to ALS and Charcot-Marie-Tooth disease (CMT2E). Conversely, we discuss how certain types of perikaryal neurofilament aggregates might confer protection in motor neuron disease. 相似文献