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1.
K. Ferrazzoli Devienne M.S. Gonalves Raddi R. Gomes Coelho W. Vilegas 《Phytomedicine》2005,12(5):378-381
Three naturally occurring isocoumarins (paepalantine, paepalantine 9-O-beta-D-glucopyranoside and paepalantine 9-O-beta-D-allopyranosyl(1 --> 6) glucopyranoside) and two semi-synthetic analogues, 9,10-acylated compound and 9-OH-10-methylated compound, structurally similar to paepalantine, were evaluated for antimicrobial activity using a spectrophotometric microdilution technique. The paepalantine was active against S. aureus, S. epidermidis, and E. faecalis while the other four compounds proved ineffective against all microorganisms tested at concentrations of 500 microg/ml. Variations in phenolic substitution at OH-9 and/or OH-10 in the paepalantine molecule resulted in compounds without antimicrobial activity. A combination of structural features, two phenolic groups as cathecolic system, forms an oxygenated system arrangement that may reflect the potentially antimicrobial properties of paepalantine. 相似文献
2.
Leandro Neves Faria Marlon Gomes Da Rocha Quirijn De Jong Van Lier Derblai Casaroli 《Plant and Soil》2010,331(1-2):299-311
Correct modeling of root water uptake partitioning over depth is an important issue in hydrological and crop growth models. Recently a physically based model to describe root water uptake was developed at single root scale and upscaled to the root system scale considering a homogeneous distribution of roots per soil layer. Root water uptake partitioning is calculated over soil layers or compartments as a function of respective soil hydraulic conditions, specifically the soil matric flux potential, root characteristics and a root system efficiency factor to compensate for within-layer root system heterogeneities. The performance of this model was tested in an experiment performed in two-compartment split-pot lysimeters with sorghum plants. The compartments were submitted to different irrigation cycles resulting in contrasting water contents over time. The root system efficiency factor was determined to be about 0.05. Release of water from roots to soil was predicted and observed on several occasions during the experiment; however, model predictions suggested root water release to occur more often and at a higher rate than observed. This may be due to not considering internal root system resistances, thus overestimating the ease with which roots can act as conductors of water. Excluding these erroneous predictions from the dataset, statistical indices show model performance to be of good quality. 相似文献
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This paper deals with the investigation on the composition and stratification of the Phebotominae activity developed in patch and clear areas of high agricultural activity. The employment of a CDC light trap proved to be a useful tool in determining the local faune. Thirteen species of sandflies and a total of 5,423 individuals were caught. The catch places situated in the ecotone were the ones in which the results reached their best, being outstanding for Psychodopygus intermedius, Lutzomyia migonei and L. fischeri. Thereby, data lead us to believe they have acrodendrophilous habit. On the other hand, when the global results were gathered according to male and female categories, the first one proved to be predominant. In the analysis of seasonal distribution for the three species cited, it was clear that the high-activity peaks were bi- and tri-modal for different seasons. P. intermedius was almost the exclusive sandfly caught at ground level in the Autumn season. This exclusiveness has practically extended itself to the catch places situated in open field. 相似文献
7.
D Tetaert V Gomes G Huet-Duvillier D Demeyer M Hublart A Boersma P Degand 《Biochemical and biophysical research communications》1987,144(3):1222-1228
High performance liquid chromatography (HPLC) procedures have been used to analyze a preparation of the variant surface glycoprotein AnTat 1.1A of Trypanosoma brucei. The native preparation gives several peaks with a high reproducibility both by reverse-phase (RP-) and gel permeation (GP-) HPLC. Under RP-HPLC conditions, nine fractions are fully resolved. The RP-HPLC fractions migrate with the same molecular weight VSG band on polyacrylamide slab gel electrophoresis and no significant differences are observed in amino acid composition among these fractions. The RP-HPLC resolution is found to be related to the ability of the VSG to polymerize as shown using GP-HPLC. These results suggest the existence of a microheterogeneity of the AnTat 1.1A VSG preparation in relation to post-translational modification of the VSG molecule. 相似文献
8.
Cloning and sequencing of the peroxisomal amine oxidase gene from Hansenula polymorpha 总被引:7,自引:0,他引:7
P G Bruinenberg M Evers H R Waterham J Kuipers A C Arnberg G AB 《Biochimica et biophysica acta》1989,1008(2):157-167
We have cloned the AMO gene, encoding the microbody matrix enzyme amine oxidase (EC 1.4.3.6) from the yeast Hansenula polymorpha. The gene was isolated by differential screening of a cDNA library, immunoselection, and subsequent screening of a H. polymorpha genomic library. The nucleotide sequence of a 3.6 kilobase stretch of DNA containing the amine oxidase (AMO) gene was determined. The AMO gene contains an open reading frame of 692 amino acids, with a relative molecular mass of 77,435. The 5' and 3' ends of the gene were mapped and show that the transcribed region measures 2134 nucleotides. The derived amino-acid sequence was confirmed by sequencing an internal proteolytic fragment of the purified protein. Amine oxidase contains the tripeptide sequence Ser-Arg-Leu, located 9 residues from the carboxy terminus, which may represent the topogenic signal for protein import into microbodies. 相似文献
9.
β-thalassemia mutations in the Portuguese population 总被引:2,自引:0,他引:2
M. P. Coutinho Gomes M. G. Gomes da Costa L. B. Braga N. T. Cordeiro-Ferreira A. Loi M. Pirastu A. Cao 《Human genetics》1988,78(1):13-15
Summary In this study we have carried out haplotype analysis on the -globin gene cluster and characterized the -thalassemia mutation by oligonucleotide hybridization in 14 patients with thalassemia major and 5 with sickle cell/-thalassemia originating from southern Portugal. We found that three mutations, namely the °-39, ° IVS-1 nt 1 and + IVS-1 nt 110 are prevalent accounting for 53%, 32% and 10% of the -thalassemia chromosomes respectively. In general each mutation was associated with a specific chromosomal haplotype; the ° mutation, however, was linked to three different haplotypes. These results indicate that three oligo-probes complementary to the most common mutations allow prenatal diagnosis by oligonucleotide analysis in 96% of the couples at risk of having offspring with thalassemia major in southern Portugal. 相似文献
10.
I. Gomes R. K. Saha G. Mohiuddin M. M. Hoq 《World journal of microbiology & biotechnology》1992,8(6):589-592
A thermophilic fungus belonging to the Deuteromyces, having pectinase and xylanase activities, was grown at its optimum temperature of 55°C. It grew over a wide pH range of 4 to 10, being optimal at 6. The fungus grew well on modified Mandels' medium in which cellulose was substituted either with hemicellulose or pectin. With citrus pectin as carbon source, 121 units/ml of pectinase activity were obtained and with larch wood xylan as carbon source, 83 units/ml of xylanase activity were obtained. 相似文献