全文获取类型
收费全文 | 3553篇 |
免费 | 227篇 |
出版年
2021年 | 32篇 |
2020年 | 17篇 |
2019年 | 33篇 |
2018年 | 41篇 |
2017年 | 38篇 |
2016年 | 80篇 |
2015年 | 97篇 |
2014年 | 135篇 |
2013年 | 145篇 |
2012年 | 226篇 |
2011年 | 253篇 |
2010年 | 195篇 |
2009年 | 144篇 |
2008年 | 193篇 |
2007年 | 195篇 |
2006年 | 173篇 |
2005年 | 182篇 |
2004年 | 157篇 |
2003年 | 179篇 |
2002年 | 163篇 |
2001年 | 47篇 |
2000年 | 31篇 |
1999年 | 60篇 |
1998年 | 59篇 |
1997年 | 45篇 |
1996年 | 59篇 |
1995年 | 43篇 |
1994年 | 46篇 |
1993年 | 32篇 |
1992年 | 53篇 |
1991年 | 35篇 |
1990年 | 43篇 |
1989年 | 29篇 |
1988年 | 21篇 |
1987年 | 17篇 |
1986年 | 15篇 |
1985年 | 19篇 |
1984年 | 31篇 |
1983年 | 23篇 |
1982年 | 31篇 |
1981年 | 33篇 |
1980年 | 21篇 |
1979年 | 36篇 |
1978年 | 20篇 |
1977年 | 19篇 |
1976年 | 19篇 |
1973年 | 14篇 |
1971年 | 15篇 |
1970年 | 16篇 |
1967年 | 16篇 |
排序方式: 共有3780条查询结果,搜索用时 46 毫秒
991.
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
992.
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
993.
von Jan M Lapidus A Del Rio TG Copeland A Tice H Cheng JF Lucas S Chen F Nolan M Goodwin L Han C Pitluck S Liolios K Ivanova N Mavromatis K Ovchinnikova G Chertkov O Pati A Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Saunders E Brettin T Detter JC Chain P Eichinger K Huber H Spring S Rohde M Göker M Wirth R Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP 《Standards in genomic sciences》2010,2(3):327-346
Archaeoglobus profundus (Burggraf et al. 1990) is a hyperthermophilic archaeon in the euryarchaeal class Archaeoglobi, which is currently represented by the single family Archaeoglobaceae, containing six validly named species and two strains ascribed to the genus 'Geoglobus' which is taxonomically challenged as the corresponding type species has no validly published name. All members were isolated from marine hydrothermal habitats and are obligate anaerobes. Here we describe the features of the organism, together with the complete genome sequence and annotation. This is the second completed genome sequence of a member of the class Archaeoglobi. The 1,563,423 bp genome with its 1,858 protein-coding and 52 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
994.
Tice H Mayilraj S Sims D Lapidus A Nolan M Lucas S Glavina Del Rio T Copeland A Cheng JF Meincke L Bruce D Goodwin L Pitluck S Ivanova N Mavromatis K Ovchinnikova G Pati A Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Detter JC Brettin T Rohde M Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Chen F 《Standards in genomic sciences》2010,2(2):168-175
Nakamurella multipartita (Yoshimi et al. 1996) Tao et al. 2004 is the type species of the monospecific genus Nakamurella in the actinobacterial suborder Frankineae. The nonmotile, coccus-shaped strain was isolated from activated sludge acclimated with sugar-containing synthetic wastewater, and is capable of accumulating large amounts of polysaccharides in its cells. Here we describe the features of the organism, together with the complete genome sequence and annotation. This is the first complete genome sequence of a member of the family Nakamurellaceae. The 6,060,298 bp long single replicon genome with its 5415 protein-coding and 56 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
995.
Nolan M Sikorski J Jando M Lucas S Lapidus A Glavina Del Rio T Chen F Tice H Pitluck S Cheng JF Chertkov O Sims D Meincke L Brettin T Han C Detter JC Bruce D Goodwin L Land M Hauser L Chang YJ Jeffries CD Ivanova N Mavromatis K Mikhailova N Chen A Palaniappan K Chain P Rohde M Göker M Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP 《Standards in genomic sciences》2010,2(1):29-37
Streptosporangium roseum Crauch 1955 is the type strain of the species which is the type species of the genus Streptosporangium. The 'pinkish coiled Streptomyces-like organism with a spore case' was isolated from vegetable garden soil in 1955. Here we describe the features of this organism, together with the complete genome sequence and annotation. This is the first completed genome sequence of a member of the family Streptosporangiaceae, and the second largest microbial genome sequence ever deciphered. The 10,369,518 bp long genome with its 9421 protein-coding and 80 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
996.
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
997.
Anja Bosy‐Westphal Elke Kossel Kristin Goele Thordis Blöcker Merit Lagerpusch Wiebke Later Martin Heller Claus C. Glüer Manfred J. Müller 《Obesity (Silver Spring, Md.)》2010,18(11):2111-2117
Pericardial adipose tissue (PAT) is positively associated with fatty liver and obesity‐related insulin resistance. Because PAT is a well‐known marker of visceral adiposity, we investigated the impact of weight loss on PAT and its relationship with liver fat and insulin sensitivity independently of body fat distribution. Thirty overweight nondiabetic women (BMI 28.2–46.8 kg/m2, 22–41 years) followed a 14.2 ± 4‐weeks low‐calorie diet. PAT, abdominal subcutaneous (SAT), and visceral fat volumes (VAT) were measured by magnetic resonance imaging (MRI), total fat mass, trunk, and leg fat by dual‐energy X‐ray absorptiometry and intrahepatocellular lipids (IHCL) by (1)H‐magnetic resonance spectroscopy. Euglycemic hyperinsulinemic clamp (M) and homeostasis model assessment of insulin resistance (HOMAIR) were used to assess insulin sensitivity or insulin resistance. At baseline, PAT correlated with VAT (r = 0.82; P < 0.001), IHCL (r = 0.46), HOMAIR (r = 0.46), and M value (r = ?0.40; all P < 0.05). During intervention, body weight decreased by ?8.5%, accompanied by decreases of ?12% PAT, ?13% VAT, ?44% IHCL, ?10% HOMA2‐%B, and +24% as well as +15% increases in HOMA2‐%S and M, respectively. Decreases in PAT were only correlated with baseline PAT and the loss in VAT (r = ?0.56; P < 0.01; r = 0.42; P < 0.05) but no associations with liver fat or indexes of insulin sensitivity were observed. Improvements in HOMAIR and HOMA2‐%B were only related to the decrease in IHCL (r = 0.62, P < 0.01; r = 0.65, P = 0.002) and decreases in IHCL only correlated with the decrease in VAT (r = 0.61, P = 0.004). In conclusion, cross‐sectionally PAT is correlated with VAT, liver fat, and insulin resistance. Longitudinally, the association between PAT and insulin resistance was lost suggesting no causal relationship between the two. 相似文献
998.
Songhet P Barthel M Röhn TA Van Maele L Cayet D Sirard JC Bachmann M Kopf M Hardt WD 《PloS one》2010,5(11):e13804
Salmonella enterica subspecies 1 serovar Typhimurium (S. Typhimurium) causes diarrhea and acute inflammation of the intestinal mucosa. The pro-inflammatory cytokines IL-17A and IL-17F are strongly induced in the infected mucosa but their contribution in driving the tissue inflammation is not understood. We have used the streptomycin mouse model to analyze the role of IL-17A and IL-17F and their cognate receptor IL-17RA in S. Typhimurium enterocolitis. Neutralization of IL-17A and IL-17F did not affect mucosal inflammation triggered by infection or spread of S. Typhimurium to systemic sites by 48 h p.i. Similarly, Il17ra(-/-) mice did not display any reduction in infection or inflammation by 12 h p.i. The same results were obtained using S. Typhimurium variants infecting via the TTSS1 type III secretion system, the TTSS1 effector SipA or the TTSS1 effector SopE. Moreover, the expression pattern of 45 genes encoding chemokines/cytokines (including CXCL1, CXCL2, IL-17A, IL-17F, IL-1α, IL-1β, IFNγ, CXCL-10, CXCL-9, IL-6, CCL3, CCL4) and antibacterial molecules was not affected by Il17ra deficiency by 12 h p.i. Thus, in spite of the strong increase in Il17a/Il17f mRNA in the infected mucosa, IL-17RA signaling seems to be dispensable for eliciting the acute disease. Future work will have to address whether this is attributable to redundancy in the cytokine signaling network. 相似文献
999.
Background
Much previous work on how normal aging affects visual enumeration has been focused on the response time required to enumerate, with unlimited stimulus duration. There is a fundamental question, not yet addressed, of how many visual items the aging visual system can enumerate in a “single glance”, without the confounding influence of eye movements.Methodology/Principal Findings
We recruited 104 observers with normal vision across the age span (age 21–85). They were briefly (200 ms) presented with a number of well- separated black dots against a gray background on a monitor screen, and were asked to judge the number of dots. By limiting the stimulus presentation time, we can determine the maximum number of visual items an observer can correctly enumerate at a criterion level of performance (counting threshold, defined as the number of visual items at which ≈63% correct rate on a psychometric curve), without confounding by eye movements. Our findings reveal a 30% decrease in the mean counting threshold of the oldest group (age 61–85: ∼5 dots) when compared with the youngest groups (age 21–40: 7 dots). Surprisingly, despite decreased counting threshold, on average counting accuracy function (defined as the mean number of dots reported for each number tested) is largely unaffected by age, reflecting that the threshold loss can be primarily attributed to increased random errors. We further expanded this interesting finding to show that both young and old adults tend to over-count small numbers, but older observers over-count more.Conclusion/Significance
Here we show that age reduces the ability to correctly enumerate in a glance, but the accuracy (veridicality), on average, remains unchanged with advancing age. Control experiments indicate that the degraded performance cannot be explained by optical, retinal or other perceptual factors, but is cortical in origin. 相似文献1000.