全文获取类型
收费全文 | 629篇 |
免费 | 26篇 |
国内免费 | 107篇 |
出版年
2023年 | 7篇 |
2022年 | 9篇 |
2021年 | 14篇 |
2020年 | 16篇 |
2019年 | 17篇 |
2018年 | 6篇 |
2017年 | 15篇 |
2016年 | 11篇 |
2015年 | 19篇 |
2014年 | 6篇 |
2013年 | 71篇 |
2012年 | 20篇 |
2011年 | 33篇 |
2010年 | 27篇 |
2009年 | 33篇 |
2008年 | 40篇 |
2007年 | 38篇 |
2006年 | 38篇 |
2005年 | 27篇 |
2004年 | 31篇 |
2003年 | 30篇 |
2002年 | 25篇 |
2001年 | 16篇 |
2000年 | 18篇 |
1999年 | 21篇 |
1998年 | 20篇 |
1997年 | 14篇 |
1996年 | 15篇 |
1995年 | 18篇 |
1994年 | 20篇 |
1993年 | 13篇 |
1992年 | 9篇 |
1991年 | 10篇 |
1990年 | 13篇 |
1989年 | 11篇 |
1988年 | 5篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 5篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1981年 | 1篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1978年 | 4篇 |
1977年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有762条查询结果,搜索用时 453 毫秒
41.
Ibatsam Khokhar Irum Mukhtar Sobia Mushtaq 《Archives Of Phytopathology And Plant Protection》2013,46(14):1347-1351
Microorganisms are increasingly exploited as a source of new biological control agents. Genus Penicillium is a source of novel bioactive molecules which can be used as antifungal agents. The objective of this study was to evaluate the antifungal potential of Penicillium strains. Culture filtrates of two Penicillium species were tested for their antifungal potential by well diffusion assays. Filtrate of Penicillium isolates showed high antifungal effects on mycelial growth of Fusarium oxysporum, Fusarium solani, Macrophomina phaseolina, Aspergillus japonicus var aculeatus and Cladosporium cladosporioides. But Penicillium italicum inhibit the fungal growth from 45 to 68% as compared to Penicillium simplissimum (25–68%). However in case of A. japonicus var aculeatus, Penicillium spp. extracts were equally effective and reduce the colony growth up to 68%. However, P. simplissimum extract was least effective in case of M. phaseolina, where it decreased the colony growth only 25%. 相似文献
42.
Leila Farahani Hasan Reza Etebarian Navazolah Sahebani Heshmatolah Aminian 《Archives Of Phytopathology And Plant Protection》2013,46(3):310-317
In this study, antagonistic yeast Candida membranifaciens was combined with different concentrations of silicon (Si; 0, 0.1, 0.3 and 0.5% wt/vol) to evaluate the control of blue mold of apple in storage at 20°C and 5°C. Preliminary studies showed that Si at 0.6% or above inhibited mycelial growth of pathogens significantly in vitro. In vitro studies showed that Si at 0.1% had lower effect on yeast growth. In vivo studies showed that combination of different concentrations of Si with C. membranifaciens improved the efficacy of yeast in control of disease better than Si and yeast alone (P < 0.05). Our result showed that the effective concentration of Si is varied based on pathogen isolates and temperature, so that the most effective concentration of Si was 0.5% for isolate P2 at 20°C and 0.5% and 0.1% for isolates P1 and P2 at 5°C. 相似文献
43.
Kumar Nishanth Bala Nambisan R. Ramya Chellapan Mohandas 《Archives Of Phytopathology And Plant Protection》2013,46(6):721-731
A specific symbiotic Bacillus sp. isolated from a rhabditid entomopathogenic nematode, Rhabditis (Oscheius) sp. was found to produce large number of bioactive compounds. The present study was conducted to determine the effect of carbon and nitrogen sources for the production of antimicrobial substances by Bacillus sp. The yield of the crude antimicrobial substances and antimicrobial activity against the test micro-organism also differed significantly when carbon and nitrogen sources in the fermentation media were changed. The antifungal activity was significantly high in yeast extract plus fructose (46.5?±?2.12?mm) followed by yeast extract plus maltose, beef extract plus fructose and meat infusion plus glucose. High pressure liquid chromatography analysis of the crude antimicrobial substances revealed different peaks with different retention time indicating that they produced different compounds. When the carbon source was not included in the fermentation media, the antimicrobial production was substantially reduced. The results indicate that carbon source in the fermentation media plays a vital role in the production of antifungal substances. It is concluded that yeast extract and fructose as nitrogen and carbon sources produced maximum activity, which can effectively control the blue mould caused by Penicillium expansum in apples and pears. 相似文献
44.
煤矿区耐镉青霉菌的分离鉴定 总被引:2,自引:0,他引:2
[目的]分离鉴定煤矸石中耐Cd2+菌株.[方法]用菌落形态和18S rRNA序列分析鉴定菌株,研究菌株的重金属耐性和在酸性煤矸石浸出液的生长能力,分析其抗氧化酶活性对重金属复合污染的响应.[结果]BJKD4菌株为青霉属(Penicillium sp.)菌,能耐29 mmol/L的Cd2+,不同重金属对BJKD4的毒性大小依次为:Cu2+>Ni2+>Cd2+>pb2+或Zn2+>Mn2+.正交试验表明BJKD4菌株能在不同浓度重金属Cd、Zn、Ni和Mn等复合污染条件下生长,SOD活性在重金属复合污染时升高,CAT活性变化依重金属的种类和浓度不同而不同;此外,BJKD4能在含有煤矸石酸性浸出液的培养基中生长,并提高其pH.[结论]BJKD4菌株能耐多种重金属,具有阻止煤矸石山淋溶液酸化的应用潜力.抗氧化酶在减缓重金属诱导的氧化胁迫中起重要作用. 相似文献
45.
The changes during growth and sporulation in activities of cells of Bacillus subtilis to incorporate various amino acids were investigated with wild-type strain and its asporogenous mutant. In the case of wild type strain the uptake of valine, phenylalanine, and proline was largest during the logarithmic growth period. The uptake of these amino acids decreased rapidly during the early stationary phase. The uptake of valine and cysteine increased again to some extent just prior to the forespore stage. The uptake of glycine and serine, however, was largest at the forespore stage at which the formation of spore coat took place. From these observed phenomena it was assumed that the remarkable incorporation of glycine and serine into the wild type strain during sporulation was closely related to the formation of spore coat. 相似文献
46.
Shigeo Aibara Takahiro Inakuma Yuhei Morita 《Bioscience, biotechnology, and biochemistry》2013,77(11):3051-3052
Penicillium strains (n=394) preserved at NBRC (the NITE Biological Resource Center) were compared as to groupings (11 species-clusters) based on phylogeny and the production of bioactive compounds. The strains in two clusters, of which P. chrysogenum and P. citrinum are representative, showed higher rates of positive strains with multi-biological activities. 相似文献
47.
《Bioscience, biotechnology, and biochemistry》2013,77(6):1230-1237
Penicillum sp. 40, which can grow in an extremely acidic medium at pH 2.0 was screened from an acidic soil. This fungus produces xylanases when grown in a medium containing xylan as a sole carbon source. A major xylanase was purified from the culture supernatant of Penicillium sp. 40 and designated XynA. The molecular mass of XynA was estimated to be 25,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. XynA has an optimum pH at 2.0 and is stable in pH 2.0-5.0. Western blot analysis using anit-XynA antibody showed that XynA was induced by xylan and repressed by glucose. Also, its production was increased by an acidic medium. The gene encoding XynA (xynA) was isolated from the genomic library of Penicillium sp. 40. The structural part of xynA was found to be 721 bp. The nucleotide sequence of cDNA amplified by RT-PCR showed that the open reading frame of xynA was interrupted by a single intron which was 58 bp in size and encoded 221 amino acids. Direct N-terminal amino acid sequencing showed that the precursor of XynA had a signal peptide composed of 31 amino acids. The molecular mass caliculated from the deduced amino acid sequence of XynA is 20,713. This is lower than that estimated by gel electrophoresis, suggesting that XynA is a glycoprotein. The predicted amino acid sequence of XynA has strong similarity to other family11 xylanases from fungi. 相似文献
48.
《Bioscience, biotechnology, and biochemistry》2013,77(10):1732-1734
A new oleanane triterpene was isolated from okara fermented with Penicillium simplicissimum ATCC 90288. Its structure was established to be 7β, 15α,24-trihydroxyolean-12-en-3,11,22-trione by spectroscopic techniques and an X-ray crystaliographic analysis. 相似文献
49.
50.