全文获取类型
收费全文 | 3099篇 |
免费 | 222篇 |
出版年
2023年 | 15篇 |
2022年 | 44篇 |
2021年 | 74篇 |
2020年 | 43篇 |
2019年 | 50篇 |
2018年 | 63篇 |
2017年 | 59篇 |
2016年 | 97篇 |
2015年 | 180篇 |
2014年 | 176篇 |
2013年 | 216篇 |
2012年 | 303篇 |
2011年 | 319篇 |
2010年 | 179篇 |
2009年 | 167篇 |
2008年 | 176篇 |
2007年 | 150篇 |
2006年 | 117篇 |
2005年 | 128篇 |
2004年 | 149篇 |
2003年 | 112篇 |
2002年 | 91篇 |
2001年 | 15篇 |
2000年 | 9篇 |
1999年 | 16篇 |
1998年 | 30篇 |
1997年 | 23篇 |
1996年 | 19篇 |
1995年 | 16篇 |
1994年 | 11篇 |
1993年 | 25篇 |
1992年 | 9篇 |
1991年 | 13篇 |
1990年 | 9篇 |
1989年 | 8篇 |
1988年 | 11篇 |
1986年 | 11篇 |
1985年 | 9篇 |
1984年 | 16篇 |
1983年 | 10篇 |
1982年 | 18篇 |
1981年 | 11篇 |
1979年 | 8篇 |
1978年 | 8篇 |
1977年 | 12篇 |
1976年 | 9篇 |
1975年 | 9篇 |
1974年 | 7篇 |
1973年 | 12篇 |
1972年 | 8篇 |
排序方式: 共有3321条查询结果,搜索用时 15 毫秒
991.
Background
Streptococcus pneumoniae is a common colonizer of the human nasopharynx and one of the major pathogens causing invasive disease worldwide. Dissection of the molecular pathways responsible for colonization, invasion, and evasion of the immune system will provide new targets for antimicrobial or vaccine therapies for this common pathogen.Methodology/Principal Findings
We have constructed mutants lacking the pneumococcal cell wall hydrolases (CWHs) LytB and LytC to investigate the role of these proteins in different phases of the pneumococcal pathogenesis. Our results show that LytB and LytC are involved in the attachment of S. pneumoniae to human nasopharyngeal cells both in vitro and in vivo. The interaction of both proteins with phagocytic cells demonstrated that LytB and LytC act in concert avoiding pneumococcal phagocytosis mediated by neutrophils and alveolar macrophages. Furthermore, C3b deposition was increased on the lytC mutant confirming that LytC is involved in complement evasion. As a result, the lytC mutant showed a reduced ability to successfully cause pneumococcal pneumonia and sepsis. Bacterial mutants lacking both LytB and LytC showed a dramatically impaired attachment to nasopharyngeal cells as well as a marked degree of attenuation in a mouse model of colonization. In addition, C3b deposition and phagocytosis was more efficient for the double lytB lytC mutant and its virulence was greatly impaired in both systemic and pulmonary models of infection.Conclusions/Significance
This study confirms that the CWHs LytB and LytC of S. pneumoniae are essential virulence factors involved in the colonization of the nasopharynx and in the progress of invasive disease by avoiding host immunity. 相似文献992.
In the Gran Chaco region, control of Triatoma infestans has been limited by persistent domestic infestations despite the efforts of the Vector Control Services. In Paraguay, this region is the highest endemic area in the country, showing high levels of indoor and outdoor infestation. Although sylvatic T. infestans have been found in the Bolivian and Argentine Chaco, similar searches for sylvatic populations of this species in Paraguay had been unsuccessful over the last 20 years. Here we present a new approach to detecting sylvatic Triatominae, using a trained dog, which has successfully confirmed sylvatic populations of T. infestans and other triatomine species in Paraguay. A total of 22 specimens corresponding to dark morph forms of T. infestans were collected, and 14 were confirmed as T. infestans by the mitochondrial cytochrome B gene analysis. Through this analysis, one of which were previously reported and a second that was a new haplotype. Triatomines were captured from amongst vegetation such as dry branches and hollows trees of different species such Aspidosperma quebracho-blanco, Bulnesia sarmientoi and Stetsonia coryne. The colonies found have been small and without apparent infection with Trypanosoma cruzi. During the study, Triatoma sordida and Triatoma guasayana have also been found in ecotopes close to those of T. infestans. 相似文献
993.
Han C Gronow S Teshima H Lapidus A Nolan M Lucas S Hammon N Deshpande S Cheng JF Zeytun A Tapia R Goodwin L Pitluck S Liolios K Pagani I Ivanova N Mavromatis K Mikhailova N Huntemann M Pati A Chen A Palaniappan K Land M Hauser L Brambilla EM Rohde M Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Detter JC 《Standards in genomic sciences》2011,4(3):361-370
Treponema succinifaciens Cwyk and Canale-Parola 1981 is of interest because this strictly anaerobic, apathogenic member of the genus Treponema oxidizes carbohydrates and couples the Embden-Meyerhof pathway via activity of a pyruvate-formate lyase to the production of acetyl-coenzyme A and formate. This feature separates this species from most other anaerobic spirochetes. The genome of T. succinifaciens 6091(T) is only the second completed and published type strain genome from the genus Treponema in the family Spirochaetaceae. The 2,897,425 bp long genome with one plasmid harbors 2,723 protein-coding and 63 RNA genes and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
994.
Chertkov O Copeland A Lucas S Lapidus A Berry KW Detter JC Del Rio TG Hammon N Dalin E Tice H Pitluck S Richardson P Bruce D Goodwin L Han C Tapia R Saunders E Schmutz J Brettin T Larimer F Land M Hauser L Spring S Rohde M Kyrpides NC Ivanova N Göker M Beller HR Klenk HP Woyke T 《Standards in genomic sciences》2011,5(1):112-120
Tolumonas auensis Fischer-Romero et al. 1996 is currently the only validly named species of the genus Tolumonas in the family Aeromonadaceae. The strain is of interest because of its ability to produce toluene from phenylalanine and other phenyl precursors, as well as phenol from tyrosine. This is of interest because toluene is normally considered to be a tracer of anthropogenic pollution in lakes, but T. auensis represents a biogenic source of toluene. Other than Aeromonas hydrophila subsp. hydrophila, T. auensis strain TA 4(T) is the only other member in the family Aeromonadaceae with a completely sequenced type-strain genome. The 3,471,292 bp chromosome with a total of 3,288 protein-coding and 116 RNA genes was sequenced as part of the DOE Joint Genome Institute Program JBEI 2008. 相似文献
995.
Göker M Daligault H Mwirichia R Lapidus A Lucas S Deshpande S Pagani I Tapia R Cheng JF Goodwin L Pitluck S Liolios K Ivanova N Mavromatis K Mikhailova N Pati A Chen A Palaniappan K Han C Land M Hauser L Pan C Brambilla EM Rohde M Spring S Sikorski J Wirth R Detter JC Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP 《Standards in genomic sciences》2011,5(3):407-415
Desulfurobacterium thermolithotrophum L'Haridon et al. 1998 is the type species of the genus Desulfurobacterium which belongs to the family Desulfurobacteriaceae. The species is of interest because it represents the first thermophilic bacterium that can act as a primary producer in the temperature range of 45-75 °C (optimum 70°C) and is incapable of growing under microaerophilic conditions. Strain BSA(T) preferentially synthesizes high-melting-point fatty acids (C(18) and C(20)) which is hypothesized to be a strategy to ensure the functionality of the membrane at high growth temperatures. This is the second completed genome sequence of a member of the family Desulfurobacteriaceae and the first sequence from the genus Desulfurobacterium. The 1,541,968 bp long genome harbors 1,543 protein-coding and 51 RNA genes and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
996.
Munk AC Lapidus A Lucas S Nolan M Tice H Cheng JF Del Rio TG Goodwin L Pitluck S Liolios K Huntemann M Ivanova N Mavromatis K Mikhailova N Pati A Chen A Palaniappan K Tapia R Han C Land M Hauser L Chang YJ Jeffries CD Brettin T Yasawong M Brambilla EM Rohde M Sikorski J Göker M Detter JC Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP 《Standards in genomic sciences》2011,4(3):342-351
Tsukamurella paurometabola corrig. (Steinhaus 1941) Collins et al. 1988 is the type species of the genus Tsukamurella, which is the type genus to the family Tsukamurellaceae. The species is not only of interest because of its isolated phylogenetic location, but also because it is a human opportunistic pathogen with some strains of the species reported to cause lung infection, lethal meningitis, and necrotizing tenosynovitis. This is the first completed genome sequence of a member of the genus Tsukamurella and the first genome sequence of a member of the family Tsukamurellaceae. The 4,479,724 bp long genome contains a 99,806 bp long plasmid and a total of 4,335 protein-coding and 56 RNA genes, and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
997.
Kiss H Nett M Domin N Martin K Maresca JA Copeland A Lapidus A Lucas S Berry KW Glavina Del Rio T Dalin E Tice H Pitluck S Richardson P Bruce D Goodwin L Han C Detter JC Schmutz J Brettin T Land M Hauser L Kyrpides NC Ivanova N Göker M Woyke T Klenk HP Bryant DA 《Standards in genomic sciences》2011,5(3):356-370
Herpetosiphon aurantiacus Holt and Lewin 1968 is the type species of the genus Herpetosiphon, which in turn is the type genus of the family Herpetosiphonaceae, type family of the order Herpetosiphonales in the phylum Chloroflexi. H. aurantiacus cells are organized in filaments which can rapidly glide. The species is of interest not only because of its rather isolated position in the tree of life, but also because Herpetosiphon ssp. were identified as predators capable of facultative predation by a wolf pack strategy and of degrading the prey organisms by excreted hydrolytic enzymes. The genome of H. aurantiacus strain 114-95(T) is the first completely sequenced genome of a member of the family Herpetosiphonaceae. The 6,346,587 bp long chromosome and the two 339,639 bp and 99,204 bp long plasmids with a total of 5,577 protein-coding and 77 RNA genes was sequenced as part of the DOE Joint Genome Institute Program DOEM 2005. 相似文献
998.
Göker M Gronow S Zeytun A Nolan M Lucas S Lapidus A Hammon N Deshpande S Cheng JF Pitluck S Liolios K Pagani I Ivanova N Mavromatis K Ovchinikova G Pati A Tapia R Han C Goodwin L Chen A Palaniappan K Land M Hauser L Jeffries CD Brambilla EM Rohde M Detter JC Woyke T Bristow J Markowitz V Hugenholtz P Eisen JA Kyrpides NC Klenk HP 《Standards in genomic sciences》2011,4(2):200-209
Odoribacter splanchnicus (Werner et al. 1975) Hardham et al. 2008 is the type species of the genus Odoribacter, which belongs to the family Porphyromonadaceae in the order 'Bacteroidales'. The species is of interest because members of the Odoribacter form an isolated cluster within the Porphyromonadaceae. This is the first completed genome sequence of a member of the genus Odoribacter and the fourth sequence from the family Porphyromonadaceae. The 4,392,288 bp long genome with its 3,672 protein-coding and 74 RNA genes and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
999.
Pati A Abt B Teshima H Nolan M Lapidus A Lucas S Hammon N Deshpande S Cheng JF Tapia R Han C Goodwin L Pitluck S Liolios K Pagani I Mavromatis K Ovchinikova G Chen A Palaniappan K Land M Hauser L Jeffries CD Detter JC Brambilla EM Kannan KP Rohde M Spring S Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Ivanova N 《Standards in genomic sciences》2011,4(2):221-232
Cellulophaga lytica (Lewin 1969) Johansen et al. 1999 is the type species of the genus Cellulophaga, which belongs to the family Flavobacteriaceae within the phylum 'Bacteroidetes' and was isolated from marine beach mud in Limon, Costa Rica. The species is of biotechnological interest because its members produce a wide range of extracellular enzymes capable of degrading proteins and polysaccharides. After the genome sequence of Cellulophaga algicola this is the second completed genome sequence of a member of the genus Cellulophaga. The 3,765,936 bp long genome with its 3,303 protein-coding and 55 RNA genes consists of one circular chromosome and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
1000.
Lapidus A Chertkov O Nolan M Lucas S Hammon N Deshpande S Cheng JF Tapia R Han C Goodwin L Pitluck S Liolios K Pagani I Ivanova N Huntemann M Mavromatis K Mikhailova N Pati A Chen A Palaniappan K Land M Hauser L Brambilla EM Rohde M Abt B Spring S Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Woyke T 《Standards in genomic sciences》2011,5(1):86-96
Flexistipes sinusarabici Fiala et al. 2000 is the type species of the genus Flexistipes in the family Deferribacteraceae. The species is of interest because of its isolated phylogenetic location in a genomically under-characterized region of the tree of life, and because of its origin from a multiply extreme environment; the Atlantis Deep brines of the Red Sea, where it had to struggle with high temperatures, high salinity, and a high concentrations of heavy metals. This is the fourth completed genome sequence to be published of a type strain of the family Deferribacteraceae. The 2,526,590 bp long genome with its 2,346 protein-coding and 53 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献