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101.
Xiang LI Yi Nan ZHENG Wen Han LIN Isabel SATTLER 《中国化学快报》2006,17(11):1466-1468
A novel butanolide, named virginaebutanolide F (1), was isolated from the lyophilized culture broth of Slreptomyces sp., along with a known compound virginaebutanolide C (2). Their structures including the stereochemistry were elucidated on the basis of extensive 1D and 2D NMR as well as HRESI-MS and CD spectroscopic analysis. 相似文献
102.
Two new polyether antibiotics 3, 5 together with three known ones 1, 2, 4 were isolated from Streptomyces hygroscopicus XM201. Based on the unambiguous NMR data assignments, their structures were determined to be 30-acetyl nigericin (1), 1-O-methyl-30-acetyl nigericin (2), 1,29-O-dimethyl-30-acetyl nigericin (3), nigericin (4), and 29-O-methyl abierixin (5), respectively. The antibacterial activities of the nigericin derivatives 1–4 were studied. Compounds 1 and 4 showed strong activities against Staphylococcus aureus ATCC25923 and Bacillus cereus 1126 with MIC of 0.25 μg/mL and 0.125 μg/mL, respectively. No inhibitory activities were observed against Escherichia coli CMCC44103 at a concentration of 25 μg/mL. Only 1 and 4 showed distinguished effects on the protoplast regeneration clones of B. cereus 1126 and E. coli CMCC44103 at a concentration of 1 μg/mL.
Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 285–288, May–June, 2009. 相似文献
103.
Lina Deng Rui Wang Guowei Wang Mingxu Liu Zhihua Liao 《Natural product research》2019,33(14):2038-2043
A novel sesquiterpenoid, roseosporol A (1), together with 12 known compounds (2–13) were isolated from the ethyl acetate extract of Lsr2-deletion mutant strain of Streptomyces roseosporus. Their structures were determined by spectroscopic methods, including NMR, HRMS, UV, IR and ECD. 相似文献
104.
FR--0001 and FR--005 are two fusants obtained through protoplast fusion between differ-ently marked derivatives of Streptomyces hygroscopicus 5102, which produce three agricul-turally important antibiotics. Although they show distinct differences in morphologicaland cultural characteristics, antimicrobial activity and metabolites, they all carry a 20.1 kbplasmid (pHZ65) with complete DNA homology. A detailed restriction map with 29 sitesfor restriction enzymes BamHI, BclI, EcoRV, KpnI, PstI, SphI, SstI and XhoI has been deter-mined. Four Strepiomyces-E. coli bifunctional plasmids, pHZ200, pHZ201, pHZ206 andpHZ207, have been constructed by the in vitro insertion of an E. coli plasmid pIJ2703 whichcarries the tsr gene (expressible in Streptomyces) and amp gene (expressible in E. coli)into the BclI or BglII sites of pHZ65. The replicability of a series of plasmids obtainedby the cloning of DNA fragments from pHZ65 into the BclI site of pIJ2703 in S. lividansshows that the essential replication region of pH 相似文献
105.
A new diketopiperazine (DKP) derivative, (6R,3Z)-3-benzylidene-6-isobutyl-1-methyl piperazine-2,5-dione (1), as well as five known DKPs 2–6 was isolated from a deep sea-derived Streptomyces sp. SCSIO 04496. The structure of 1 was elucidated using a combination of 1D and 2D NMR, HR-ESI-MS and chiral-phase HPLC techniques. Compounds 1–6 did not show cytotoxic activity at a concentration of 100 μM in bioactivity assay. 相似文献
106.
Istamycin aminoglycosides profiling and their characterization in Streptomyces tenjimariensis ATCC 31603 culture using high‐performance liquid chromatography with tandem mass spectrometry 下载免费PDF全文
Nguyen Huu Hoang Nguyen Lan Huong Byul Kim Jae Kyung Sohng Yeo Joon Yoon Je Won Park 《Journal of separation science》2016,39(24):4712-4722
A high‐performance liquid chromatography with electrospray ionization ion trap tandem mass spectrometry method was developed and validated for the robust profiling and characterization of biosynthetic congeners in the 2‐deoxy‐aminocyclitol istamycin pathway, from the fermentation broth of Streptomyces tenjimariensis ATCC 31603. Gradient elution on an Acquity CSH C18 column was performed with a gradient of 5 mM aqueous pentafluoropropionic acid and 50% acetonitrile. Sixteen natural istamycin congeners were profiled and quantified in descending order; istamycin A, istamycin B, istamycin A0, istamycin B0, istamycin B1, istamycin A1, istamycin C, istamycin A2, istamycin C1, istamycin C0, istamycin X0, istamycin A3, istamycin Y0, istamycin B3, and istamycin FU‐10 plus istamycin AP. In addition, a total of five sets of 1‐ or 3‐epimeric pairs were chromatographically separated using a macrocyclic glycopeptide‐bonded chiral column. The lower limit of quantification of istamycin‐A present in S. tenjimariensis fermentation was estimated to be 2.2 ng/mL. The simultaneous identification of a wide range of 2‐deoxy‐aminocyclitol‐type istamycin profiles from bacterial fermentation was determined for the first time by employing high‐performance liquid chromatography with tandem mass spectrometry analysis and the separation of istamycin epimers. 相似文献
107.
Vineomycin A1 (1) and B2 (2) were isolated from the culture broth of marine actinomycete Streptomyces sp. A6H. Five hydrolysis products were obtained by rational hydrolysis and methanolysis of the fermentation extract. Their structures were characterised as aquayamycin (3), vineomycinone B2 (4), 9-C-D-olivosyltetrangulol (5), 7-O-methylgaltamycinone (6) and vineomycinone B2 methyl ester (7). In addition to these compounds, two ester derivatives, vineolactone A (8) and vineomycinone B2 benzyl ester (9) of compound 4 were generated semisynthetically. Compound 6 is a new analogue of galtamycinone, while compounds 8 and 9 are new members of vineomycins. Cytotoxic activities and antimicrobial activities were determined for all compounds. The results indicate that only compound 1 showed significant activities with IC50 value of 0.34 μM against H1975 and MIC value of 4 μg/mL against Staphylococcus aureus. 相似文献
108.
Vanessa M. Nepomuceno Hiyoung Kim Yuanqing Ding Hongbing Liu Mark Sadek Daneel Ferreira Sesselja Omarsdottir Brian T. Murphy 《Tetrahedron》2018,74(52):7421-7425
A collaborative program to discover new specialized metabolites from aquatic environments of Iceland led to the deconvolution of tetrahydroisoquinoline amide E/Z rotamers [(E/Z)-N-acetyl-MY336-a; 1] and conformers produced by a Streptomyces sp. All structures were elucidated by NMR and MS analysis, and interpretation of electronic circular dichroism (ECD) data. ECD and optical rotation (OR) simulations permitted the unequivocal assignment of the absolute configuration of compound 1 and provided an important example of delineating the spectroscopic contributions of equilibrating rotamers and boat/chair conformers of a common natural product scaffold. 相似文献
109.
Production of C-terminal amidated recombinant salmon calcitonin in Streptomyces lividans 总被引:4,自引:0,他引:4
Salmon calcitonin (sCT) is one of the many bioactive peptides that require C-terminal amidation for full biologic activity.
To produce fully bioactive sCT in large scale, we constructed Streptomyces lividans [pMSA], an engineering Streptomyces strain. In the expression vector, glycine-extended sCT, the substrate for amidation, and rat α-amidating enzyme cDNA were
cloned under the control of the strong constitutive promoter from the Streptomyces fradiae aph gene in pIJ680. Both were expressed in a secretory manner by the recombinant strain using the expression and secretion signals
of melC1. Extracellularly expressed recombinant sCT was purified to near homogeneity and characterized by enzyme immunoassay, followed
by direct amino-terminal sequencing. High-performance liquid chromatography, matrixassisted laser desorption ionization-time-of-flight
mass spectrometry, and bioassay in vivo demonstrated purified product to be equivalent to synthetic standard. Thus, the engineered
Streptomyces strain can produce bioactive, C-terminal amidated recombinant sCT in the culture supernatant directly. The ease of the recombinant
process, as well as its potential for scale-up, makes it adaptable to production demands for sCT, and it may be applied to
other bioactive peptides that need C-terminal amidation. 相似文献
110.
Klaus Edegger 《Tetrahedron》2004,60(3):583-588
Asymmetric biohydrolysis of trisubstituted terpenoid oxiranes (rac-1a-rac-3a) was accomplished by employing the epoxide hydrolase activity Rhodococcus and Streptomyces spp. Depending on the biocatalyst, the biohydrolysis proceeded in an enantio-convergent fashion and gave the corresponding vic-diols in up to 97% ee at conversions beyond the 50%-threshold. In order to avoid a depletion of the ee of product by further oxidative metabolism, bioconversions had to be conducted in an inert atmosphere with exclusion of molecular oxygen. The synthetic applicability of this method was demonstrated by the asymmetric total synthesis of the monoterpenoid coumarin (R)-(+)-Marmin in 95% ee. 相似文献