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排序方式: 共有174条查询结果,搜索用时 15 毫秒
1.
Malolactic fermentation (MLF), which improves organoleptic properties and biologic stability of some wines, may cause wine spoilage if uncontrolled. Bacteriocins were reported as efficient preservatives to control MLF through their bactericidal effect on malolactic bacteria. Leuconostoc mesenteroides subsp. cremoris W3 isolated from wine produces an inhibitory substance that is bactericidal against malolactic bacteria in model wine medium. Treatment of the culture supernatant of strain W3 with proteases eliminated the inhibitory activity, which proved that it is a true bacteriocin and we tentatively termed it mesentericin W3. The bacteriocin inhibited the growth of food-borne pathogenic bacteria such as Enterococcus faecalis, Listeria monocytogenes, and malolactic bacteria. It was active over a wide pH range and stable to organic solvents and heat. Mesentericin W3 was purified to homogeneity by a pH-mediated cell adsorption–desorption method, cation exchange, hydrophobic interaction, and reverse-phase chromatography. Matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectroscopy (MS) and partial amino acid sequence analysis revealed that mesentericin W3 was identical to mesentericin Y105. 相似文献
2.
Biosorption of chromium(VI) on to cone biomass of Pinus sylvestris was studied with variation in the parameters of pH, initial metal ion concentration and agitation speed. The biosorption of Cr(VI) was increased when pH of the solution was decreased from 7.0 to 1.0. The maximum chromium biosorption occurred at 150 rpm agitation. An increase in chromium/biomass ratio caused a decrease in the biosorption efficiency. The adsorption constants were found from the Freundlich isotherm at 25 degrees C. The cone biomass, which is a readily available biosorbent, was found suitable for removing chromium from aqueous solution. 相似文献
3.
Early detection of bladder cancer is particularly important since it dramatically affects the survival rates. However, neither urinary cytology nor tumor markers that are currently used are sensitive enough for the early detection of bladder cancer or recurrent disease. The ras genes are frequently mutated in cancer. In this study, we investigated the diagnostic potential of ras mutation analysis in urinary sediments of patients with bladder cancer using a single-strand conformation polymorphism analysis and polymerase chain reaction. Mutation in codon 12 of the H-ras gene was observed in 39% of the patients. Our results indicate that this approach may significantly improve diagnostic sensitivity in detecting bladder tumors. 相似文献
4.
Robert Brus Dalibor Ballian Faruk Bogunić Martin Bobinac Marilena IdžOjtić 《Plant biosystems》2013,147(2):278-285
Abstract In most European countries, the service tree (Sorbus domestica L.) is a rare and threatened species and its conservation has been recognised as a priority. The aim of this study was to asses its morphologic variation in the western and central part of the Balkan Peninsula and in southern Central Europe. Three populations were analysed: one in Serbia, one in Bosnia and Herzegovina and one in Slovenia. In each population 30 trees were selected, and from each tree 30 leaves were collected for morphometric analysis based on nine leaflet morphological traits. Univariate (ANOVA) and multivariate (MANOVA) analysis of variance were used to estimate the variation within- and between populations and a discriminant analysis was performed to examine the structure of the between-population differences. The values of particular morphological traits found in our study did not differ considerably from the values reported elsewhere. The results revealed significant within- and between population variation. Variation within populations was highly significant for all the scored leaf morphological traits, while variation between populations was significant for all the studied traits except for the leaflet length. The discrimination between the three populations was significant. High percentages of correctly classified samples demonstrate good discriminating employability of the analysed leaf morphological traits and indicate differentiation of the analysed populations. 相似文献
5.
Ender Karaca Elif Karakoc-Aydiner Omer Faruk Bayrak Sevgi Keles Serhat Sevli Isil B. Barlan Adnan Yuksel Talal A. Chatila Mustafa Ozen 《Gene》2013
Protein tyrosine kinases (PTKs) play an important role in T cell development and activation. In vitro and in vivo defects, resulting in variable deficiencies in thymic development and in T cell antigen receptor (TCR) signal transduction, in PTKs have been shown. ZAP70, one of those PTKs, is a 70-kDa tyrosine phosphoprotein and associates with the ζ chain and undergoes tyrosine phosphorylation following TCR stimulation. It is expressed in T and natural killer (NK) cells. Several mutations were shown to lead to an autosomal recessive form of severe combined immunodeficiency disease (SCID). 相似文献
6.
In this report we describe the first patient ever found to have azoospermia in association with both exceptional complex chromosomal rearrangements and microdeletions at two translocation breakpoints. A 36-year-old male who had been suffering from male factor infertility was admitted to our clinic. The patient also displayed mild dysmorphia. An analysis of the patient's semen revealed azoospermia. GTG banding revealed the presence of an exceptional complex chromosomal rearrangement involving chromosomes 1, 4, 10 and 14. Using subtelomeric FISH analysis, the patient's karyotype was designated as 46,XY,t(1;10)(q43q44;q21q26.1)(CEB108/T7+,D1S3738-;10PTEL006+,D10S2290+, D1S3738+), ins(14;4) (q31.3;q23q33)(D14S1420+; D4S3359+, D4S2930+). Array-CGH analysis revealed two microdeletions at the 4q22.3q23 and 14q31.1q31.3 chromosomal regions. We suggest that microdeletions at the 4q22.3q23 and 14q31.1q31.3 chromosomal regions associated with both an exceptional complex chromosomal rearrangement and the Homo sapiens chromosome 4 open reading frame 37 (C4orf37) gene located at the 4q22.3q23 region might be associated with male factor infertility. 相似文献
7.
Single-cell protein production from ram horn hydrolysate by bacteria 总被引:23,自引:0,他引:23
The alcoholysis (transesterification) of the refined cotton seed oil of Turkish origin with primary and secondary alcohols was investigated in the presence of an immobilized enzyme from Candida antarctica, commercially called Novozym 435 in a solvent-free medium. The optimum conditions of the methanolysis were as follows: 30% enzyme based on oil weight; oil/alcohol molar ratio 1:4; temperature: 50 degrees C and reaction time: 7 h. Maximum methyl esters (ME) yield was 91.5%. At the same conditions cotton seed oil was converted with short-chain primary and secondary alcohols to its corresponding esters with conversions between 72% and 94%. Our results indicated that alcoholysis products of cotton seed oil could be used as valuable intermediates in oleochemistry. 相似文献
8.
9.
N. Pojskic A. Ahmic Kapur Leejla J. Hadzihalilovic R. Hadziselimovic 《Human Evolution》2005,20(2-3):137-147
Ten qualitative traits were observed in two isolated human populations in Bosnia for prewar and postwar periods. Due to recent
war in Bosnia and Herzegovina two million citizens was forced to migrate. Dramatic migration effects occurred in the investigated
populations. Population characteristics found were geographic isolation, high levels of marital distance “zero”, patrilocality
and propagation isolation. Relative recessive allele frequencies of ten qualitative traits were calculated. Average heterozigosity,
genetic differentiation, total heterozigosity, within populations heterozigosity, genetic distance and relative measures based
on results of genetic distance analysis were observed. The total number of observed individuals was 1875. We have observed
1209 individuals in prewar period (Bijela population 731 and Memici population 478) and 666 individuals in the postwar period
(Bijela population 248 and Memici population 478). Results ofFst andGst analysis showed changed degree of genetic differentiation across observed loci. Significant changes in differentiation were
recorded for crooked little finger and PTC tasting. Modest changes of gene differentiation were recorded for ear lobe type
and thumb proximal extensibility. Genetic distance analisis between Bijela and Memici has lower value after then before the
war, but genetic distance between Bijela-prewar and Bijela-postwar has higher value, as well as Memici-prewar and Memici-postwar
genetic distance. Genetic distance between Bijela-prewar and Memiciprewar, as well as Bijela-postwar and Memici-postwar showed
similarity. Constructed dendrogram based on results of genetic distance analyses indicated two clusters groups (1. Bijela-prewar,
Memici-prewar; 2. Bijela-postwar, Memici-postwar). Changed genetic differentiation and results of genetic distance analyses
indicated possibility of significant impact of forced migration in genetic structure of observed populations. 相似文献
10.
Kucukgergin C Sanli O Tefik T Aydın M Ozcan F Seckin S 《Molecular biology reports》2012,39(1):193-198
We aimed to investigate the association between manganese superoxide dismutase (MnSOD) Ala-9-Val gene polymorphism and the
initiation and/or progression of prostate cancer (PCa) as well as to evaluate its potential interactions with advanced age
and smoking status. MnSOD Ala-9-Val gene polymorphism was carried out in 134 (mean age 64.1 ± 7.48) PCa patients and 159 (mean
age 62.5 ± 7.53) healthy controls with serum prostate specific antigen (PSA) levels (<4 ng/ml) and normal digital rectal examination
(DRE) findings in this prospectively designed study. PCa patients were classified as low stage disease (T1 or T2 and N0M0 stages) and high stage disease (T3 or T4 and N0M0 or N1 or M1 stages). Genotypes for MnSOD Ala-9-Val gene polymorphism were identified by using polymerase chain reaction-restriction fragment
length polymorphism (PCR-RFPL). Despite lack of association between different genotypes of MnSOD Ala-9-Val gene polymorphism
and the presence of PCa, patients with Ala/Ala genotype were at an increased risk of high stage disease compared with those
with the Val/Val genotype [odds ratio (OR), 3.77; 95% CI, 1.30–10.94; P = 0.012]. However, no significant difference was observed in the distribution of each genotype among PCa patients, with respect
to tumor grade. On the other hand, smoking status and aging did not seem to change the association between genotypes and PCa
risk. Ala/Ala genotype of MnSOD polymorphism may have an effect on adverse features of PCa such as high stage disease. 相似文献