全文获取类型
收费全文 | 273篇 |
免费 | 26篇 |
出版年
2020年 | 3篇 |
2019年 | 2篇 |
2018年 | 4篇 |
2017年 | 8篇 |
2016年 | 10篇 |
2015年 | 12篇 |
2014年 | 12篇 |
2013年 | 7篇 |
2012年 | 17篇 |
2011年 | 19篇 |
2010年 | 12篇 |
2009年 | 14篇 |
2008年 | 7篇 |
2007年 | 10篇 |
2006年 | 12篇 |
2005年 | 5篇 |
2004年 | 7篇 |
2003年 | 4篇 |
2002年 | 4篇 |
2001年 | 8篇 |
2000年 | 1篇 |
1999年 | 4篇 |
1998年 | 13篇 |
1997年 | 8篇 |
1996年 | 7篇 |
1995年 | 8篇 |
1994年 | 1篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1990年 | 6篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 7篇 |
1984年 | 2篇 |
1983年 | 4篇 |
1982年 | 6篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 8篇 |
1976年 | 6篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1972年 | 2篇 |
1971年 | 2篇 |
1970年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有299条查询结果,搜索用时 125 毫秒
91.
Valentin Loux Mahendra Mariadassou Sintia Almeida Hélène Chiapello Amal Hammani Julien Buratti Annie Gendrault Valérie Barbe Jean-Marc Aury Stéphanie-Marie Deutsch Sandrine Parayre Marie-No?lle Madec Victoria Chuat Gwena?l Jan Pierre Peterlongo Vasco Azevedo Yves Le Loir Hélène Falentin 《BMC genomics》2015,16(1)
Background
Propionibacterium freudenreichii (PF) is an actinobacterium used in cheese technology and for its probiotic properties. PF is also extremely adaptable to several ecological niches and can grow on a variety of carbon and nitrogen sources. The aim of this work was to discover the genetic basis for strain-dependent traits related to its ability to use specific carbon sources. High-throughput sequencing technologies were ideal for this purpose as they have the potential to decipher genomic diversity at a moderate cost.Results
21 strains of PF were sequenced and the genomes were assembled de novo. Scaffolds were ordered by comparison with the complete reference genome CIRM-BIA1, obtained previously using traditional Sanger sequencing. Automatic functional annotation and manual curation were performed. Each gene was attributed to either the core genome or an accessory genome. The ability of the 21 strains to degrade 50 different sugars was evaluated. Thirty-three sugars were degraded by none of the sequenced strains whereas eight sugars were degraded by all of them. The corresponding genes were present in the core genome. Lactose, melibiose and xylitol were only used by some strains. In this case, the presence/absence of genes responsible for carbon uptake and degradation correlated well with the phenotypes, with the exception of xylitol. Furthermore, the simultaneous presence of these genes was in line the metabolic pathways described previously in other species. We also considered the genetic origin (transduction, rearrangement) of the corresponding genomic islands. Ribose and gluconate were degraded to a greater or lesser extent (quantitative phenotype) by some strains. For these sugars, the phenotypes could not be explained by the presence/absence of a gene but correlated with the premature appearance of a stop codon interrupting protein synthesis and preventing the catabolism of corresponding carbon sources.Conclusion
These results illustrate (i) the power of correlation studies to discover the genetic basis of binary strain-dependent traits, and (ii) the plasticity of PF chromosomes, probably resulting from horizontal transfers, duplications, transpositions and an accumulation of mutations. Knowledge of the genetic basis of nitrogen and sugar degradation opens up new strategies for the screening of PF strain collections to enable optimum cheese starter, probiotic and white biotechnology applications.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1467-7) contains supplementary material, which is available to authorized users. 相似文献92.
Micro‐computed tomography assessment of vertebral column defects in retinoic acid‐Induced rat model of myelomeningocele
下载免费PDF全文
![点击此处可从《Birth defects research. Part A, Clinical and molecular teratology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
93.
Barbe L. Prinzing A. Mony C. Abbott B. W. Santonja M. Hoeffner K. Guillocheau S. Cluzeau D. Francez A.-J. Le Bris N. Jung V. 《Ecosystems》2020,23(1):124-136
Ecosystems - Litter decomposition is central to ecosystem functioning and depends, under constant abiotic conditions, on litter quality and decomposer activity. During the assembly of a plant... 相似文献
94.
95.
Jean-Fran?ois Humbert Valérie Barbe Amel Latifi Muriel Gugger Alexandra Calteau Therese Coursin Aurélie Lajus Vanina Castelli Sophie Oztas Ga?lle Samson Cyrille Longin Claudine Medigue Nicole Tandeau de Marsac 《PloS one》2013,8(8)
Microcystis aeruginosa is one of the most common bloom-forming cyanobacteria in freshwater ecosystems worldwide. This species produces numerous secondary metabolites, including microcystins, which are harmful to human health. We sequenced the genomes of ten strains of M. aeruginosa in order to explore the genomic basis of their ability to occupy varied environments and proliferate. Our findings show that M. aeruginosa genomes are characterized by having a large open pangenome, and that each genome contains similar proportions of core and flexible genes. By comparing the GC content of each gene to the mean value of the whole genome, we estimated that in each genome, around 11% of the genes seem to result from recent horizontal gene transfer events. Moreover, several large gene clusters resulting from HGT (up to 19 kb) have been found, illustrating the ability of this species to integrate such large DNA molecules. It appeared also that all M. aeruginosa displays a large genomic plasticity, which is characterized by a high proportion of repeat sequences and by low synteny values between the strains. Finally, we identified 13 secondary metabolite gene clusters, including three new putative clusters. When comparing the genomes of Microcystis and Prochlorococcus, one of the dominant picocyanobacteria living in marine ecosystems, our findings show that they are characterized by having almost opposite evolutionary strategies, both of which have led to ecological success in their respective environments. 相似文献
96.
Complete genome sequence of a beneficial plant root-associated bacterium, Pseudomonas brassicacearum
Ortet P Barakat M Lalaouna D Fochesato S Barbe V Vacherie B Santaella C Heulin T Achouak W 《Journal of bacteriology》2011,193(12):3146
To shed light on the genetic equipment of the beneficial plant-associated bacterium Pseudomonas brassicacearum, we sequenced the whole genome of the strain NFM421. Its genome consists of one chromosome equipped with a repertoire of factors beneficial for plant growth. In addition, a complete type III secretion system and two complete type VI secretion systems were identified. We report here the first genome sequence of this species. 相似文献
97.
Song JJ Aswad R Kanaan RA Rico MC Owen TA Barbe MF Safadi FF Popoff SN 《Journal of cellular physiology》2007,210(2):398-410
Mesenchymal cell (MC) condensation or the aggregation of MCs precedes chondrocyte differentiation and is required for subsequent cartilage formation during endochondral ossification. In this study, we used micromass cultures of C3H10T1/2 cells as an in vitro model system for studying MC condensation and the events important for this process. Transforming growth factor beta1 (TGF-beta1) served as the initiator of MC condensation in our model system and we were interested in determining whether CTGF functions as a downstream mediator of TGF-beta1. CTGF is a matricellular protein that has been found to be expressed in MC condensations and in the perichondrium. Micromass cultures of C3H10T1/2 cells condensed under TGF-beta1 stimulation concomitant with dramatic up-regulation of CTGF mRNA and protein levels. CTGF silencing by either CTGF siRNA or CTGF antisense oligonucleotide approaches showed that TGF-beta1-induced condensation was CTGF dependent. Furthermore, silencing of CTGF expression resulted in significant reductions in cell proliferation and migration, events that are crucial during MC condensation. In addition, up-regulation of Fibronectin (FN) and suppression of Sox9 expression by TGF-beta1 was also found to be mediated by CTGF. Immunofluorescence of developing mouse vertebrae showed that CTGF, TGF-beta1 and FN were co-expressed in condensations of MCs, while Sox9 expression was low at this stage. During subsequent chondrogenesis, Sox9 expression was high in chondrocytes while CTGF expression was limited to the perichondrium. Thus, CTGF is an essential downstream mediator of TGF-beta1-induced MC condensation through its effects on cell proliferation and migration. CTGF is also involved in up-regulating FN and suppressing Sox9 expression during TGF-beta1 induced MC condensation. 相似文献
98.
Hernández Pérez A E Cerna Chávez JC Delgado Ortiz M Beltrán Beache LM Tapia Vargas YM Ochoa Fuentes 《Phyton》2019,88(1):11-13
Mexico is the main producer, consumer and exporter
of avocado in the world, being Michoacan the main producer state
contributing more than 80% of the national production. There
are phytopathogens that decimate the production causing the
death of the tree. Root samples were collected in avocado trees
that showed the characteristic symptomatology of the disease
known as avocado sadness, the sampling was carried out in four
of the main avocado producing towns, in the state of Michoacan,
Mexico. The isolation consisted in sowing root tissue in Petri
dishes with V8®-PARPH culture medium, subsequently they were
identified morphologically and for species level it was determined
by molecular biology, with the PCR-ITS technique. Pathogenicity
tests were performed in triplicate with avocado seedlings with more
than six leaves. After 24 hours, the inoculated plants expressed
decay in the apical part, after 120 hours the leaves showed yellowing
and after 15 days there was a generalized wilt on the stem and
leaves, re-isolating the phytopathogen Phytopythium vexans.
This study confirms the first report of the oomycete P. vexans
affecting avocado trees in the most important producing region of
the Mexican Republic. 相似文献
99.
Y Deng J Zhao D Sakurai KM Kaufman JC Edberg RP Kimberly DL Kamen GS Gilkeson CO Jacob RH Scofield CD Langefeld JA Kelly ME Alarcón-Riquelme BIOLUPUS GENLES Networks JB Harley TJ Vyse BI Freedman PM Gaffney KM Sivils JA James TB Niewold RM Cantor W Chen BH Hahn EE Brown PROFILE BP Tsao 《Arthritis research & therapy》2012,14(Z3):A5
100.
Emmanuel Cornillot Kamel Hadj-Kaddour Amina Dassouli Benjamin Noel Vincent Ranwez Beno?t Vacherie Yoann Augagneur Virginie Brès Aurelie Duclos Sylvie Randazzo Bernard Carcy Fran?oise Debierre-Grockiego Stéphane Delbecq Karina Moubri-Ménage Hosam Shams-Eldin Sahar Usmani-Brown Frédéric Bringaud Patrick Wincker Christian P. Vivarès Ralph T. Schwarz Theo P. Schetters Peter J. Krause André Gorenflot Vincent Berry Valérie Barbe Choukri Ben Mamoun 《Nucleic acids research》2012,40(18):9102-9114
We have sequenced the genome of the emerging human pathogen Babesia microti and compared it with that of other protozoa. B. microti has the smallest nuclear genome among all Apicomplexan parasites sequenced to date with three chromosomes encoding ∼3500 polypeptides, several of which are species specific. Genome-wide phylogenetic analyses indicate that B. microti is significantly distant from all species of Babesidae and Theileridae and defines a new clade in the phylum Apicomplexa. Furthermore, unlike all other Apicomplexa, its mitochondrial genome is circular. Genome-scale reconstruction of functional networks revealed that B. microti has the minimal metabolic requirement for intraerythrocytic protozoan parasitism. B. microti multigene families differ from those of other protozoa in both the copy number and organization. Two lateral transfer events with significant metabolic implications occurred during the evolution of this parasite. The genomic sequencing of B. microti identified several targets suitable for the development of diagnostic assays and novel therapies for human babesiosis. 相似文献