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Regarding the involvement of free radicals and oxidative reactions in protein glycoxidation processes, compounds with antioxidant activities have been tested in order to reduce or to stop glycoxidation. In this study, we evaluated the antioxidant potential of several organic fractions of Teucrium polium extract using different model systems including total antioxidant capacity by the phosphomolybdenum method, ferric reducing antioxidant power and Trolox equivalent antioxidant capacity assays, antioxidant activity in linoleic acid emulsion system and scavenging of 1,1-diphenyl-2-picrylhydrazyl radical. The results indicated that the ethyl acetate (EtOAc) fraction of T. polium possesses the highest antioxidant activity and total phenolic and flavonoid contents. Given the link between glycation and oxidation, we proposed that the EtOAc fraction might possess significant in vitro antiglycation activities as well. Our data confirmed the inhibitory effect of EtOAc fraction on bovine serum albumin (BSA) glycoxidation measured in terms of advanced glycation end products (AGEs) and pentosidine formation as well as protein oxidation markers including protein carbonyl formation (PCO) and loss of protein thiols. Reducing sugars such as ribose and glucose increase fluorescence intensity of glycated BSA in terms of total AGEs and pentosidine during 21 day of exposure. Moreover, sugars cause more PCO formation and also oxidize thiol groups more in glycated than in native BSA. EtOAc extract at different concentrations (10–100 μg/ml) has significantly quenched the fluorescence intensity of glycated BSA. Furthermore, we demonstrated that the inhibitory effect of EtOAc extract in preventing oxidative protein damages including effect on PCO formation and thiol oxidation which are believe to form under the glycoxidation process. These results clearly demonstrate that, the EtOAc fraction, owning to its antioxidant content, is capable of suppressing the formation of AGEs and protein oxidation in vitro.  相似文献   
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OBJECTIVE: To evaluate the mass treatment of ascariasis in rural areas of Hamadan Province, Islamic Republic of Iran. METHODS: A control programme in rural areas of Hamadan Province, which began in November 1997, involved giving all persons a single dose of 400 mg albendazole at intervals of three months. The efficacy of the treatment was evaluated by the formalin-ether concentration technique for stool examination and by the Stoll quantitative method. FINDINGS: The average rate of infection with Ascaris before treatment was 53.3%, ranging from 40% in Hamadan district to 75% in Toysercan. Two areas, Malayer and Nahavand, were excluded from the programme because the infection rates were only 13% and 4%, respectively. After two years of mass treatment the infection rate had decreased to 6%. The proportion of positive cases excreting only unfertilized eggs increased to 32%. No side-effects of mass treatment were observed. CONCLUSION: Systematic mass treatment giving high coverage proved to be very effective in the control of ascariasis, notwithstanding a lack of other preventive measures.  相似文献   
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Background  

An observational case series was used to study the virulence characteristics and genotypes of paired Staphylococcus epidermidis isolates cultured from intraocular samples and from periocular environment of patients with postcataract surgery endophthalmitis.  相似文献   
25.

Background  

We describe corneal endothelial cell density and morphology in normal Iranian eyes and compare endothelial cell characteristics in the Iranian population with data available in the literature for American and Indian populations.  相似文献   
26.
When two differently colored, superimposed patterns of dots rotate in opposite directions, this yields the percept of two superimposed transparent surfaces. If observers are cued to attend to one set of dots, they are impaired in making judgments about the other set. Since the two sets of dots are overlapping, the cueing effect cannot be explained by spatial attention. This has led to the interpretation that the impairment reflects surface-based attentional selection. However, recent single-unit recording studies in monkeys have found that attention can modulate the gain of neurons tuned for features such as color. Thus, rather than reflecting the selection of a surface, the behavioral effects might simply reflect a reduction in the gain of color channels selective for the color of the uncued set of dots (feature-based attention), as if viewing the surfaces through a colored filter. If so, then the impairment should be eliminated when the two surfaces are made the same color. Instead, we find that the impairment persists with no reduction in strength. Our findings thus rule out the color gain explanation.  相似文献   
27.
Safety profile of morphine following surgery in neonates.   总被引:2,自引:0,他引:2  
OBJECTIVE: To determine the effect of morphine on duration of mechanical ventilation, apnoea and hypotension among full-term neonates who underwent thoracic or abdominal surgery in a level III neonatal intensive care unit. METHOD: Medical records of 82 infants were reviewed retrospectively and data including patient demographics, clinical diagnosis, type of surgery, postoperative opioid administration, duration of mechanical ventilation, hypotension, apnoea and pain scores (premature infant pain profile (PIPP) score) were collected. RESULT: Sixty-two neonates (76%) received morphine following surgery as a continuous intravenous infusion during the postoperative period. Linear regression analysis showed that morphine dosage and duration were significantly associated with the duration of mechanical ventilation. An increase in morphine infusion rate by 10 microg kg(-1) h(-1) was associated with an increase in the duration of mechanical ventilation by 24 h (P<0.0001) and an increase in morphine duration of 1 hour was associated with a longer duration of mechanical ventilation by 38 min (P<0.0001). Logistic regression analysis showed no association between morphine infusion rate or duration and hypotension. Apnoea was not associated with morphine dosage or duration of infusion in neonates receiving morphine following extubation. Score on the PIPP correlated significantly with morphine infusion rate across time (r=0.47, P<0.01). CONCLUSION: Postoperative morphine dose and duration may prolong the duration of mechanical ventilation but there are no significant dose-dependent effects on other parameters including apnoea or hypotension following extubation in term neonates. More research is needed to determine the safety profile of morphine for management of pain in non-ventilated neonates.  相似文献   
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The low rate of understanding and the limited domain of attention are two important and distinctive characteristics of mental retardation. One of the important strategies to provide effective education for these subjects is to lessen the backgrounds and impacts of these affective factors. The aim of this research was to find the effect of computer games program on the amount of mentally retarded persons' attention. Sixty educable male mentally retarded subjects were selected from two 24-h care centres in Tehran. The Toulouse-Pieron Scale was used to determinate the subjects' attention at pre-post test. Members of the experimental group were subjected to 35 sets of computer games. After use of the sets of computer games, the attention scores of the subjects were assessed immediately after the intervention and 5 weeks later. The results showed that exactly after the intervention the average attention scores of the experimental group were significantly higher than those of the control group. But, 5 weeks after the intervention, there was actually no significant difference.  相似文献   
30.
The present study has been carried out to investigate the effect of aqueous extract of shallot (Allium ascalonicum) and garlic (Allium satium) on the fasting insulin resistance index (FIRI) and intraperitoneal glucose tolerance test (IPGTT) of fructose-induced insulin resistance rats. Male albino Wistar rats were fed either normal or high-fructose diet for a period of eight weeks. Fasting blood glucose level, fasting blood triglyceride level, FIRI, and the area under the glucose tolerance curve were significantly elevated in fructose-fed animals. Fructose-induced insulin resistance rats treated by aqueous shallot or garlic extract (500 mg/kg body weight/day, i.p.) for duration of eight weeks. Control animals only received normal saline (0.9%). The results showed that neither shallot nor garlic extracts significantly altered the FIRI and the IPGTT at the fourth week after treatment. The fasting blood glucose in fructose-induced insulin resistance animals has been significantly decreased in 8-week treated animals by both shallot and garlic extracts. Shallot extract administration, but not garlic extract, for a period of eight weeks can significantly improve the intraperitoneal glucose tolerance and diminish the FIRI. These results indicate that shallot and garlic extracts have a hypoglycemic influence on the fructose-induced insulin resistance animals and aqueous shallot extract is a stronger hypoglycemic agent than the garlic extract.  相似文献   
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