全文获取类型
收费全文 | 153篇 |
免费 | 16篇 |
国内免费 | 2篇 |
出版年
2022年 | 2篇 |
2021年 | 2篇 |
2019年 | 2篇 |
2018年 | 3篇 |
2017年 | 3篇 |
2016年 | 3篇 |
2015年 | 6篇 |
2014年 | 5篇 |
2013年 | 4篇 |
2012年 | 9篇 |
2011年 | 4篇 |
2010年 | 4篇 |
2009年 | 5篇 |
2008年 | 8篇 |
2007年 | 5篇 |
2006年 | 6篇 |
2005年 | 4篇 |
2004年 | 9篇 |
2003年 | 4篇 |
2002年 | 6篇 |
2001年 | 2篇 |
1998年 | 3篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 6篇 |
1989年 | 5篇 |
1988年 | 2篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1974年 | 2篇 |
1970年 | 1篇 |
1967年 | 3篇 |
1964年 | 1篇 |
1960年 | 1篇 |
1956年 | 1篇 |
1934年 | 1篇 |
1929年 | 1篇 |
1914年 | 1篇 |
1913年 | 1篇 |
排序方式: 共有171条查询结果,搜索用时 15 毫秒
1.
2.
3.
Carly P. Rosewarne Phillip B. Pope Stuart E. Denman Christopher S. McSweeney Paraic O��Cuiv Mark Morrison 《Microbial ecology》2011,61(2):448-454
Recent studies have shown the microbial biofilms adherent to plant biomass in the gastrointestinal tracts of humans and other herbivores are quite different to planktonic populations. If these biofilm communities are to be properly characterized by metagenomics methods, then the microbial desorption methods used must ensure the phylogenetic diversity and genetic potential recovered is biologically valid. To that end, we describe here two different methods for desorbing microbes tightly adherent to plant biomass; and used PCR-DGGE analyses of the Bacteria and Archaea rrs genes to show both these desorption methods were effective in recovering the adherent microbial biofilm with no apparent biases in microbe recovery. We also present a derivation of the ??repeated bead beating and column (RBB+C) purification?? method of DNA extraction that results in the recovery of high molecular weight DNA. These DNA samples can be fragmented and size fractionated by sucrose density gradient centrifugation, bypassing the use of gel-plug lysis and pulsed-field gel electrophoresis separation of DNA for metagenomic library constructions. 相似文献
4.
DALDINIA CONCENTRICA ATTACKING THE WOOD OF FRAXINUS EXCELSIOR 总被引:1,自引:0,他引:1
5.
Hernandez-Trejo A B Estrada-Drouaillet JA López-Santillán C Rios-Velasco SE Varela-Fuentes R Rodríguez-Herrera E Osorio-Hernández 《Phyton》2019,88(1):47-54
The control of Spodoptera frugiperda is based
on synthetic insecticides, so some alternatives are the use of
entomopathogenic fungi (EF) and neem extract. The objective of
the study was to evaluate in vitro effectiveness of native EF and
neem extracts on S. frugiperda larvae. Six EF were identified by
DNA sequencing of ITS regions from three EF (Fusarium solani,
Metarrhizium robertsii, Nigrospora spherica and Penicillium
citrinum). They were evaluated in concentrations of 1 × 10⁸ spores/
mL. In addition, a second bioassay was carried out evaluating
only F. solani, M. robertsii and N. sphaerica and the addition
of vegetable oil. On the other hand, extraction of secondary
metabolites from neem seed (Azadirachta indica) was carried
out by performing, mass (g) and solvent volume (mL ethanol
and water) combinations, which were subjected to microwaves
and ultrasound. Subsequently, these extracts were evaluated
in concentrations of 3%, 4% and 5%. A survival analysis was
performed for each of the bioassays. With respect to the results
of the first bioassay, F. solani obtained a probability of survival of
0.476 on the seventh day, while in the second bioassay, M. robertsii
obtained 0.488 survival probability. This suggests that the expected
percentage of larvae that stay alive on the sixth day is 48.8%.
However, in the evaluation of the neem extract the combination
1:12/70% to 4% caused 84% mortality of larvae. The use of native
HE and neem extracts has potential for the control of S. frugiperda. 相似文献
6.
Carrie Brady Gavin Hunter Susan Kirk Dawn Arnold Sandra Denman 《Systematic and applied microbiology》2014
Gram-negative, facultatively anaerobic bacteria were isolated from symptomatic oak tissue in the UK and USA. Partial gyrB sequencing placed ten strains in the genus Brenneria, with B. goodwinii as the closest phylogenetic relative. The strains were investigated further using a polyphasic approach including MLSA (based on partial gyrB, rpoB, infB and atpD gene sequences), 16S rRNA gene sequencing, DNA–DNA relatedness studies and both phenotypic and chemotaxonomic assays. The MLSA and 16S rRNA gene analyses separated the strains into two groups based on origin, suggesting that they belong to Brenneria as two novel species. However, the DNA–DNA relatedness values revealed a closer relationship between the groups and indicated that they should belong to the same species. As the two groups of strains from the UK and USA can be differentiated from each other phenotypically and by ERIC PCR fingerprints, it is proposed to classify them as novel subspecies of a novel Brenneria species. The name Brenneria roseae sp. nov. (FRB 222T = LMG 27714T = NCPPB 4581T) is proposed, with Brenneria roseae subsp. roseae ssp. nov. (FRB 222T = LMG 27714T = NCPPB 4581T) for the strains from the UK and Brenneria roseae subsp. americana ssp. nov. (FRB 223T = LMG 27715T = NCPPB 4582T) for the strains from the USA. 相似文献
7.
8.
9.
Effect of sulfur supplements on cellulolytic rumen micro-organisms and microbial protein synthesis in cattle fed a high fibre diet 总被引:1,自引:0,他引:1
AIM: To examine the effect of sulfur-containing compounds on the growth of anaerobic rumen fungi and the fibrolytic rumen bacteria Ruminococcus albus, Ruminococcus flavefaciens and Fibrobacter succinogenes in pure culture and within the cattle rumen. METHODS AND RESULTS: The effect of two reduced sulfur compounds, 3-mercaptopropionic acid (MPA) or 3-mercapto-1-propanesulfonic acid as the sole S source on growth of pure fibroyltic fungal and bacterial cultures showed that these compounds were capable of sustaining growth. An in vivo trial was then conducted to determine the effect of sulfur supplements (MPA and sodium sulfate) on microbial population dynamics in cattle fed the roughage Dichanthium aristatum. Real-time PCR showed significant increases in fibrolytic bacterial and fungal populations when cattle were supplemented with these compounds. Sulfate supplementation leads to an increase in dry matter intake without a change in whole tract dry matter digestibility. CONCLUSIONS: Supplementation of low S-containing diets with either sodium sulfate or MPA stimulates microbial growth with an increase in rumen microbial protein supply to the animal. SIGNIFICANCE AND IMPACT OF THE STUDY: Through the use of real-time PCR monitoring, a better understanding of the effect of S supplementation on discrete microbial populations within the rumen is provided. 相似文献
10.
Quantitation and diversity analysis of ruminal methanogenic populations in response to the antimethanogenic compound bromochloromethane 总被引:11,自引:1,他引:10
Methyl coenzyme-M reductase A (mcrA) clone libraries were generated from microbial DNA extracted from the rumen of cattle fed a roughage diet with and without supplementation of the antimethanogenic compound bromochloromethane. Bromochloromethane reduced total methane emissions by c. 30%, with a resultant increase in propionate and branched chain fatty acids. The mcrA clone libraries revealed that Methanobrevibacter spp. were the dominant species identified. A decrease in the incidence of Methanobrevibacter spp. from the clone library generated from bromochloromethane treatment was observed. In addition, a more diverse methanogenic population with representatives from Methanococcales, Methanomicrobiales and Methanosacinales orders was observed for the bromochloromethane library. Sequence data generated from these libraries aided in the design of an mcrA-targeted quantitative PCR (qPCR) assay. The reduction in methane production by bromochloromethane was associated with an average decrease of 34% in the number of methanogenic Archaea when monitored with this qPCR assay. Dissociation curve analysis of mcrA amplicons showed a clear difference in melting temperatures for Methanobrevibacter spp. (80-82 degrees C) and all other methanongens (84-86 degrees C). A decrease in the intensity of the Methanobrevibacter spp. specific peak and an increase for the other peak in the bromochloromethane-treated animals corresponded with the changes within the clone libraries. 相似文献