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71.
PER-1 type beta-lactamases were screened among ceftazidime-resistant clinical isolates of Acinetobacter spp. and Pseudomonas aeruginosa. A total of 176 non-repetitive isolates (84 Acinetobacter spp. and 92 P. aeruginosa) were collected during a three month surveillance period. Isolates were obtained from seven intensive care units of seven university hospitals. All strains were screened for bla(PER-1) alleles by PCR. Of the strains, 31% and 55.4% of Acinetobacter spp. and P. aeruginosa were positive for bla(PER-1) type genes, respectively.  相似文献   
72.
The aim of this study was to investigate the protective effects of erdosteine and vitamins C and E (VCE) on the lungs after performing hind limb ischemia–reperfusion (I/R) by assessing oxidative stress, plasma copper (Cu), and zinc (Zn) analysis. The animals were divided randomly into four groups as nine rats each as follows: control, I/R, I/R plus erdosteine, and I/R plus VCE combination. I/R period for 60 min was performed on the both hind limbs of all the rats in the groups of I/R, erdosteine with I/R, VCE with I/R allowing 120 min of reperfusion. The animals received orally erdosteine one time in a day and 3 days before I/R in the erdosteine group. In the VCE group, the animals VCE combination received one time in a day and 3 days before I/R, although placebo was given to control and I/R group animals. Lung lipid peroxidation (malondialdehyde [MDA]) level, superoxide dismutase (SOD), and catalase activities were increased, although lung glutathione (GSH) and plasma Zn levels decreased in I/R group in lung tissue compared with the control group. Serum MDA level, creatine kinase, and lactate dehydrogenase activities were increased in I/R group compared with the control. Lung MDA and plasma Zn levels and lung SOD activity were decreased by erdosteine administration, whereas lung GSH levels after I/R increased. The plasma Zn levels and lung SOD activity were decreased by VCE administration, although the plasma Cu and lung GSH levels increased after I/R. In conclusion, erdosteine has an antioxidant role on the values in the rat model, and it has more protective affect than in VCE in attenuating I/R-induced lung injury in rats.  相似文献   
73.
Gentiana cruciata L. (cross gentian) is a medicinal and ornamental plant. The root extracts of this species are known to exhibit many curative properties. The natural Gentiana populations are exposed to great danger because of their uncontrolled usage. In this study, hairy roots from Gentiana cruciata L. stem and leaf explants belonging to three different clones were induced by inoculation with four different Agrobacterium rhizogenes wild strains namely A4, 15834, 8196 and R1000. Induction of the root transformation was significantly dependent on the explant type used. On the other hand, the genotype and bacterial strain had no significant effect on hairy root formation. Hairy root formation percentages of the explants varied between 5.6–33.3% in the stem explants, and between 0.0–6.7% in the leaf explants. Transformations of the hairy roots were confirmed by PCR using rolC specific primers, and revealed the absence of contaminating A. rhizogenes with virC primers. Total of twelve hairy root clones were obtained, and their secondary metabolite content was also analyzed by HPLC. Quantitative results exhibited that gentiopicroside was the most abundant compound in all root samples. Furthermore, metabolites such as loganic acid, swertiamarin, and sweroside were also identified and quantified in the samples.  相似文献   
74.
目的:从块根芍药中分离出一株产红色素的内生菌并对其进行鉴定。方法:通过PCR方法扩增XJU-PA-6的16S rD-NA,并与GeneBank中已鉴定菌的16S rDNA序列对比,用N-J方法构建系统进化树,用Bootstraping法对其评估。同时结合其形态特征、生理生化检测、G+C mol %含量对XJU-PA-6进行鉴定。并利用紫外-可见光谱法对XJU-PA-6产生的红色素进行分析。结果:XJU-PA-6的16S rDNA序列与EF195349 Serratia sp.同源性为99 %,G+C mol %含量为57.8mo1 %。红色素的最大吸收波长为533.8nm。结论:将菌株XJU-PA-6鉴定为粘质沙雷氏菌。XJU-PA-6产生的红色素初步推测为灵菌红素。  相似文献   
75.
BackgroundThe cell cycle checkpoint kinase 2 (CHEK2) protein participates in the DNA damage response in many cell types. Germline mutations in CHEK2 (1100delC, IVS2+1G>A and I157T) have been impaired serine/threonine kinase activity and associated with a range of cancer types. This hospital-based case–control study aimed to investigate whether CHEK2 1100delC, IVS2+1G>A and I157T mutations play an important role in the development of colorectal cancer (CRC) in Turkish population.MethodsA total of 210 CRC cases and 446 cancer-free controls were genotyped for CHEK2 mutations by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and allele specific-polymerase chain reaction (AS-PCR) methods.ResultsWe did not find the CHEK2 1100delC, IVS2+1G>A and I157T mutations in any of the Turkish subjects.ConclusionOur result demonstrate for the first time that CHEK2 1100delC, IVS2+1G>A and I157T mutations have not been agenetic susceptibility factor for CRC in the Turkish population. Overall, our data suggest that genotyping of CHEK2 mutations in clinical settings in the Turkish population should not be recommended. However, independent studies are need to validate our findings in a larger series, as well as in patients of different ethnic origins.  相似文献   
76.
The production of galacto-oligosaccharides (GOS) from lactose by A. oryzae beta-galactosidase immobilized on cotton cloth was studied. The total amounts and types of GOS produced were mainly affected by the initial lactose concentration in the reaction media. In general, more and larger GOS can be produced with higher initial lactose concentrations. A maximum GOS production of 27% (w/w) of initial lactose was achieved at 50% lactose conversion with 500 g/L of initial lactose concentration. Tri-saccharides were the major types of GOS formed, accounting for more than 70% of the total GOS produced in the reactions. Temperature and pH affected the reaction rate, but did not result in any changes in GOS formation. The presence of galactose and glucose at the concentrations encountered near maximum GOS greatly inhibited the reactions and reduced GOS yield by as much as 15%. The cotton cloth as the support matrix for enzyme immobilization did not affect the GOS formation characteristics of the enzyme, suggesting no diffusion limitation in the enzyme carrier. The thermal stability of the enzyme increased approximately 25-fold upon immobilization on cotton cloth. The half-life for the immobilized enzyme on cotton cloth was more than 1 year at 40 degrees C and 48 days at 50 degrees C. Stable, continuous operation in a plugflow reactor was demonstrated for 2 weeks without any apparent problem. A maximum GOS production of 21 and 26% (w/w) of total sugars was attained with a feed solution containing 200 and 400 g/L of lactose, respectively, at pH 4.5 and 40 degrees C. The corresponding reactor productivities were 80 and 106 g/L/h, respectively, which are at least several-fold higher than those previously reported.  相似文献   
77.
78.
Abstract

Pectinesterase (PE) in Malatya apricot pulp (Prunus armeniaca L.) was extracted and purified through (NH4)2SO4 precipitation, dialysis, and DEAE-Sephadex gel filtration chromatography. The samples obtained from the dialysis procedure, named partially purified enzyme, were used for characterization of the apricot pectinesterase. The effect of various factors such as pH, temperature, heat, and storage stability on the partially purified apricot PE enzyme was investigated. Optimum pH value was 9.0 for PE with 1% pectin in 0.1 N NaCl (w/v). The optimum temperature for apricot PE was found to be 60°C on standard analysis conditions. Heat inactivation studies showed a decrease in enzymatic activity at temperatures above 70°C. Km and Vmax values were 0.77 mM and 1.75 µmol min?1 mg?1 for apricot PE. Five inhibitors were tested in the study; the most effective inhibitor was found to be sodium carbonate (100% inhibition). The order of inhibitory effectiveness was: Na2CO3, iodine, lauril sulphate, AgNO3, EDTA. Thermal inactivation data indicated that apparent activation energy with pectin substrate was 2.96 kcal mol?1 for the enzyme. Ascorbic acid, CaCl2, and KCl showed activatory effect on the apricot PE enzyme.  相似文献   
79.
80.
N G-Nitro-l-arginine methyl ester hydrochloride (L-NAME) is a non-specific nitric oxide (NO) inhibitor and it has been used to eliminate the role of NO in many studies like animal models for hypertension. In this study, we aimed to investigate whether lisinopril treatment has any biochemical and/or histopathological effect on rat liver tissue in a L-NAME-induced hypertension model. Forty-eight 6-weeks-old male Spraque–Dawley rats were used in the study. The animals used in the study were randomly divided into four equal groups. To induce hypertension, L-NAME was added to drinking water at a concentration of 600 mg/l and each rat was given 75 mg/kg/day of L-NAME for 6 weeks. Tail cuff systolic blood pressure (SBP) was measured at first, third, and sixth weeks. There was a significant difference between the experiment groups and controls. In only lisinopril given and L-NAME plus lisinopril administered groups, each rat was given 10 mg/kg of lisinopril for 6 weeks. At the end of the study, the animals were sacrificed. Blood and tissue samples were collected for biochemical and histopathological analysis. It has been observed that mean NO level was significantly decreased in L-NAME given group (p<0.05). Mean ALT levels were significantly increased in lisinopril and L-NAME plus lisinopril given groups, when compared with the control group (p<0.05). AST levels were in normal range in all groups (p>0.05). Hepatocyte degeneration was prominent in lisinopril given group, whereas mononuclear cell infiltration was significant in L-NAME given groups. Although the beneficial effects in L-NAME-induced hypertension treatment, lisinopril can lead to some unexpected results like hepatocyte degeneration, serum enzyme level elevation, and slight mononuclear cell infiltration.  相似文献   
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