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31.
《Fungal Ecology》2021
Vitis vinifera (grapevines) can form mutualistic associations with endophytic fungi. However, to date, there is not much information on the influence of endophytic Fusarium isolates on grapevine growth, oenological characteristics or their capabilities to suppress disease. In the present study, it was demonstrated on two grapevine varieties, in a field experiment, under natural conditions, that three isolates of Fusarium do indeed enter into mutualistic interactions with grapevines. Results indicate a complementary relationship between grape yield and Fusarium colonization. Plants treated with Fusarium isolates not only showed increased yield, but also had fewer losses due to shriveling and also had more robust development under unfavorable weather conditions. Furthermore, treatment with isolates of Fusarium solani and Fusarium subglutinans resulted in significantly lower gray mold incidence at rates of 80%. 相似文献
32.
Sato S Iwata F Yamada S Kawahara H Katayama M 《Bioorganic & medicinal chemistry letters》2011,21(23):7099-7101
New anthramycin-type analogues, designated usabamycin A-C (1, 2 and 3), have been isolated from cultures of Streptomyces sp. NPS853, a bacterium found in marine sediments. The structures of the new compounds were established on the basis of extensive spectroscopic analyses including 1D- and 2D-NMR ((1)H-(1)H COSY, HSQC, and HMBC) experiments. The usabamycins show weak inhibition of HeLa cell growth and selective inhibition of serotonin (5-hydroxytrypamine) 5-HT(2B) uptake. 相似文献
33.
In this study the antagonistic activity among 55 Gluconacetobacter diazotrophicus strains, belonging to 13 electrophoretic types (ETs), in culture media was analyzed. Antagonistic effects were seen only in strains belonging to two ETs named ET-1 and ET-3. Two out of 29 ET-1 strains, and 3 out of 7 ET-3 strains of G. diazotrophicus showed antagonistic effects against many other strains belonging to all the ETs of this species analyzed, and against closely related strains of Gluconacetobacter species, including Gluconacetobacter johannae, Gluconacetobacter azotocaptans and Gluconacetobacter liquefaciens but not against other phylogenetically distant bacterial species. Results showed that the substance responsible of such antagonistic activity is a low molecular mass molecule (approximately 3400 Da), stable from pH 3.5 to 8.5, and very stable at 4 degrees C for 10 months. This substance was sensitive to proteases, and the antagonistic activity was lost after 2 h at 95 degrees C. All of these features show that the substance is related to bacteriocin-like molecules. The antagonistic substance should be chromosomally encoded because ET-3 strains of G. diazotrophicus do not harbor any plasmids. The antagonistic ability of ET-3 strains of G. diazotrophicus could be an advantage for the natural colonization of the sugarcane environment, as was observed in experiments with micropropagated sterile sugarcane plantlets co-inoculated with a bacteriocin-producer strain and a bacteriocin-sensitive strain of G. diazotrophicus. In these experiments, both in the rhizosphere as well as inside the roots, the bacteriocin-sensitive population decreased drastically. In addition, this study shows that inside the plants there may exist antagonistic interactions among endophytic bacteria like to those described among the rhizospheric community. 相似文献
34.
High diversity of endophytic fungi from the pharmaceutical plant, Heterosmilax japonica Kunth revealed by cultivation-independent approach 总被引:8,自引:0,他引:8
Heterosmilax japonica Kunth is well recognized for its diuretic effects in China. However, little is known about its endophytic fungi. In this study, microbial communities inhabiting the stems of H. japonica in spring and summer were investigated by light microscopy and cultivation-independent approaches, such as RFLP analysis and sequencing of rDNA ITS library. Molecular phylogenetic analysis showed that a broad spectrum of fungi, including Mycosphaerella, Phomopsis, Aureobasidium, Cladosporium, Glomerella, Botryosphaeria, Guignardia, is able to colonize the plants internally. Particularly, several rDNA sequences determined in this study like YJ4-61 are not specifically affiliated with any currently documented fungal sequences in the public database. Several sequence types, such as YJ4-9 and YJ4-70, are significantly similar to some uncultured environmental samples. Furthermore, our result also showed that the samples collected in spring harbored more abundant endophytic populations than that in summer, implying a seasonal fluctuation for the endophytes in H. japonica. 相似文献
35.
Chemical investigations of the culture broth from an endophytic fungus Eupenicillium sp. have afforded two natural products phomoxins B (1) and C (2) as well as the previously reported fungal metabolite eupenoxide (3). Compounds 1 and 2 both contain a cyclic carbonate moiety that is rare among natural products. This paper reports the full spectroscopic characterisation of phomoxins B (1) and C (2) by NMR, UV, IR and MS data. All compounds were inactive against a panel of nosocomial microbes. 相似文献
36.
Silva GH Teles HL Zanardi LM Marx Young MC Eberlin MN Hadad R Pfenning LH Costa-Neto CM Castro-Gamboa I da Silva Bolzani V Araújo AR 《Phytochemistry》2006,67(17):1964-1969
Five cadinane sesquiterpenes derivatives were isolated by bioassay-guided fractionation from Phomopis cassiae, an endophytic fungus isolated from Cassia spectabilis. The structures of the two diastereoisomeric 3,9,12-trihydroxycalamenenes (1, 2); 3,12-dihydroxycalamenene (3); 3,12-dihydroxycadalene (4) and 3,11,12-trihydroxycadalene (5) were established on the basis of analyses of 1D and 2D NMR and HRTOFMS experiments. Antifungal activity of the isolates was evaluated against Cladosporium sphaerospermum and Cladosporium cladosporioides, revealing 5 as the most active compound. 相似文献
37.
目的:对来自海洋软珊瑚的链霉菌6-1(Streptomyces variabilis strain 6-1)进行次级代谢产物的分离和鉴定,寻找具有生物活性的化合物,为人类健康服务。方法:采用液体培养基对分自海洋软珊瑚Scleronephthya sp中的链霉菌6-1(Streptomyces variabi-lis strain 6-1)进行发酵培养,用乙酸乙酯对发酵液进行萃取;采用半制备高效液相色谱(semi-preparative HPLC)分离方法对乙酸乙酯萃取物进行分离纯化,得到单体化合物;运用电喷雾质谱(ESI-MS)、核磁共氢振(1H NMR)、核磁共振碳谱(13C NMR)和物理性质对所得单体化合物进行结构鉴定。结果:从海洋链霉菌6-1(strain 6-1)发酵液的乙酸乙酯萃取物中分离得到3个单体化合物,分别鉴定为:7,4'-二羟基异黄酮(1)、5,7,4'-三羟基异黄酮(2)和丁烯酸内酯-Ⅰ(3)。结论:丁烯酸内酯-Ⅰ是从链霉菌属首次分离得到,化合物1和2均是从Streptomyces variabilis中首次分离得到;变异链霉菌6-1(Streptomyces variabilis strain 6-1)可以作为活性化合物3(丁烯酸内酯-Ⅰ)的重要来源。 相似文献
38.
Tian X.L. Cao L.X. Tan H.M. Zeng Q.G. Jia Y.Y. Han W.Q. Zhou S.N. 《World journal of microbiology & biotechnology》2004,20(3):303-309
The populations of endophytic fungi and actinomycetes from four rice cultivars in the Panyu district (Site 1) and Wushan district
(Site 2) in Guangdong province, South China, were studied. The preponderant endophytic fungi and actinomycetes isolated belonged
to Fusarium and Streptomyces respectively. The incidence of Streptomycetes griseofuscus ranged from 36.1 to 69% out of all the different rice cultivars from the two sites. It is the commonest population of endophytic
actinomycetes, and constituted the greatest part of all the antagonistic communities. The distributions of endophytic fungi
and actinomycetes in roots and leaves were different, endophytic fungi from leaves were diverse, some were organ-specific.
More diverse endophytic actinomycetes were isolated from roots than from leaves. The endophytic fungi isolated from rice in
Site 2 were more diverse than that in Site 1. The diversity of the endophytic actinomycetes, however, was less than that in
Site 1. Acid soil in Site 2 is ideal for the growth and colonization of fungi while the alkaline soil in Site 1 is better
for the growth and colonization of actinomycetes. The results suggested that differences in the chemical composition of soil
could influence the endophytic microbial communities of rice plants. The endophytic fungi and actinomycetes isolated from
poor-growing seedlings and susceptible rice cultivars were more abundant than that the disease-resistant counterparts. In
the dual culture and activity detection of the metabolites, 41.2% of all the isolated endophytic fungi showed antagonism to
rice pathogens. Fifty percent of all the isolated endophytic actinomycetes were antagonistic to those pathogens. The percentage
of Streptomyces griseofuscus and hygroscopicus reached 55.4 and 21.4% of all the active actinomycetes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
39.
Isolation of endophytic fungi from leaves of Pasania edulis and their within-leaf distributions 总被引:2,自引:0,他引:2
Endophytic fungi were isolated from leaves of Pasania edulis, one of the most important trees of the warm temperate forests in southern Kyushu, by the surface sterilization method using
H2O2 as a sterilizing agent. From a tree in the Experimental Nursery of Kagoshima University, located at the city of Kagoshima,
Phyllosticta sp. and Colletotrichum spp. were frequently isolated. From a stand in a laurel forest in Mt. Takakuma, an ascomycetous fungus (Ascomycete sp. 1)
and Phomopsis sp. were frequently isolated. Phyllosticta sp. was isolated more frequently from petiole segments and leaf segments with midrib and Phomopsis sp. from petiole segments and leaf-base segments with midrib than other segments. Colletotrichum spp. were isolated less frequently from petioles and Ascomycete sp. 1 from petiole segments and leaf-base segments with midrib
than other segments. As possible causes of such biases in within-leaf distributions of the endophytes, differences in infection
modes and negative interactions of major endophytes within leaves are suggested.
Received: December 13, 2001 / Accepted: June 7, 2002
Acknowledgments The authors thank the staff members of the Experimental Forests of Kagoshima University for enabling the present study.
Correspondence to:K. Hata 相似文献
40.
H G Floss 《Journal of industrial microbiology & biotechnology》2001,27(3):183-194
The evolution of the field of biosynthesis from the unravelling of the mode of formation of natural products to the use of
such knowledge to create new compounds is reviewed using examples from the author's laboratory. The discussion focuses on
the mode of operation of type II (spore pigment PKS) and type I (rifamycin PKS) polyketide synthases and their diversion to
generate unnatural products, and on the genetics and biochemistry of deoxysugar formation in granaticin biosynthesis as a
prerequisite to combinatorial enzymatic synthesis of unusual glycosides. Journal of Industrial Microbiology & Biotechnology (2001) 27, 183–194.
Received 21 September 1999/ Accepted in revised form 13 September 2000 相似文献