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81.
In a biological system the product of free-radical induced-lipid peroxidation are conjugated dienes (CDs), lipid peroxides and malondialdehyde (MDA). Its control depends on antioxidant activities. Antioxidant defend the body system by controlling the damage caused by the free radicals. This paper describes lipid peroxidation process and antioxidant activities present in three species of holothuroid obtained from the coastal waters of Terengganu, Malaysia. Among the three species studied, the coelomic fluid of Bohadschia mamorata vitiensis contained the highest level of protein (7.24 + 0.04)g/L. The coelomic fluid of Stichopus badionotus Selenka contained the highest level of superoxide dismutase (SOD) (9.46 + 0.99)X 105 IU/g protein, MDA (16.46 + 1.28)nmol/g protein and total antioxidant activities (AOA) (58.81 + 5.70) %. In Stichopus variegatus Semper the coelomic fluid only demonstrated the highest level of CDs (94.19 + 11.34) RU/g protein compared with the other two species. This preliminary study indicated that some form of antioxidant activities are present in the coelomic fluid of holothuroids.  相似文献   
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The fluoropyrimidines act by inhibiting thymidylate synthase (TS). Recent studies have shown that patients' risk of severe fluoropyrimidine‐associated toxicity is affected by polymorphisms in the 5′‐untranslated region of TYMS, the gene encoding TS. A G>C substitution in the promoter enhancer region of TYMS, rs183205964 (known as the 2RC allele), markedly reduces TS activity in vitro, but its clinical relevance is unknown. We determined rs183205964 in 1605 patients previously enrolled in a prospective multicenter study. Associations between putative low TS expression genotypes (3RC/2RC, 2RG/2RC, and 2RC/2RC) and severe toxicity were investigated using univariable and multivariable logistic regression. Activity of TS and TYMS gene expression were determined in peripheral blood mononuclear cells (PBMCs) of a patient carrying genotype 2RC/2RC and of a control group of healthy individuals. Among 1,605 patients, 28 patients (1.7%) carried the 2RC allele. Twenty patients (1.2%) carried a risk‐associated genotype (2RG/2RC, n=13; 3RC/2RC, n=6; and 2RC/2RC, n=1), the eight remaining patients had genotype 3RG/2RC. Early severe toxicity and toxicity‐related hospitalization were significantly more frequent in risk‐associated genotype carriers (OR 3.0, 95%CI 1.04–8.93, p=0.043 and OR 3.8, 95%CI 1.19–11.9, p=0.024, respectively, in multivariable analysis). The patient with genotype 2RC/2RC was hospitalized twice and had severe febrile neutropenia, diarrhea, and hand‐foot syndrome. Baseline TS activity and gene expression in PBMCs of this patient, and a healthy individual with the 2RC allele, were found to be within the normal range. Our study suggests that patients carrying rs183205964 are at strongly increased risk of severe, potentially life‐threatening, toxicity when treated with fluoropyrimidines.  相似文献   
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Chronic skin ulcers are rare among healthy young adults. Local injection of cocaine and heroin has been identified as a cause of chronic skin ulcers in young adults abusing intravenous drugs. These patients use both engorged veins surrounding the ulcers and the granulation tissue itself for the injection of drugs. We believe that chronic skin ulcers in young adults should be a marker for intravenous drug abuse, and should be considered in the differential diagnosis of nonhealing wounds.  相似文献   
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Purpose: In this study, the relationship between the plasma levels of melatonin and intercellular adhesion molecule-1 (ICAM-1), which plays role in several intercellular interactions including inflammatory and immune responses, and early neurocognitive functions associated with ischaemia-reperfusion injury during open heart surgery is examined.Methods: Forty patients who were to undergo elective coronary artery bypass grafting (CABG) were divided into two groups, those who underwent their operations at 8 AM (group I; n = 20) and those who underwent their operations at 1 PM (group II; n = 20). Blood samples were collected prior to surgery (S1), when the aortic cross clamp was removed (S2) and 4 (S3) and 24 h after the surgery (S4). Neuropsychiatric assessment was conducted one day before and seven days after surgery.Results: Melatonin levels measured during and after surgery were also significantly higher in Group 1. ICAM-1 levels were significantly lower in Group 1 at S2 and S3. Significant deterioration was observed in postoperative neurocognitive function compared with preoperative functions in Group 2 more than Group 1.Conclusion: We hypothesise that the greater preservation of neurocognitive functions in the morning patients is associated with elevated melatonin levels, which reduce the damage from ischaemia-reperfusion injury.  相似文献   
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This paper presents the results of the physical and elastic properties of the ternary zinc oxyfluoro tellurite glass system. Systematic series of glasses (AlF3)x(ZnO)y(TeO2)z with x = 0–19, y = 0–20 and z = 80, 85, 90 mol% were synthesized by the conventional rapid melt quenching technique. The composition dependence of the physical, mainly density and molar volume, and elastic properties is discussed in term of the AlF3 modifiers addition that are expected to produce quite substantial changes in their physical properties. The absence of any crystalline peaks in the X-ray diffraction (XRD) patterns of the present glass samples indicates the amorphous nature. The addition of AlF3 lowered the values of the densities in ternary oxyfluorotellurite glass systems. The longitudinal and transverse ultrasonic waves propagated in each glass sample were measured using a MBS8020 ultrasonic data acquisition system. All the velocity data were taken at 5 MHz frequency and room temperature. The longitudinal modulus (L), shear modulus (G), Young’s modulus (E), bulk modulus (K) and Poisson’s ratio (σ) are obtained from both velocities data and their respective density. Experimental data shows the density and elastic moduli of each AlF3-ZnO-TeO2 series are found strongly depend upon the glass composition. The addition of AlF3 modifiers into the zinc tellurite causes substantial changes in their density, molar volume as well as their elastic properties.  相似文献   
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