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71.
目的评估人工髓核材料聚乙烯醇水凝胶/聚乙烯纤维复合物的生物相容性。方法根据ISO10993-1标准,采用细胞毒性试验(琼脂扩散法)、皮内刺激试验、Ame's致突变试验、微核试验和体内植入(360天)试验对聚乙烯醇水凝胶/聚乙烯纤维复合物的生物相容性进行评估。结果聚乙烯醇水凝胶/聚乙烯纤维复合物的细胞毒性评分小于Ⅰ级,细胞生长无明显抑制现象,对皮内无刺激作用,Ames致突变试验为阴性,微核出现率为3.48‰,无致突变反应。体内植入符合植入材料生物学评价要求。结论聚乙烯醇水凝胶/聚乙烯纤维复合物具有良好的生物安全性,是一种无毒、对皮肤及肌肉、椎间隙无刺激作用的生物医用材料,在动物体内不引起排异反应,可应用于临床。 相似文献
72.
In a laboratory study of psychomotor sensitivity to alcohol, twins were asked “Would you drive a car now?” at 1, 2, and 3 h after drinking a standard dose of ethanol (0.75 g/kg). Correlations among these binary items, the Eysenck personality scales, and age were investigated using PRELIS and LISREL. Willingness to drive and Extraversion correlate at all three times in both males and females. In males, willingness to drive also correlates with Psychoticism, and in females it correlates negatively with the Lie (or Social Desirability) scale. Most correlations between cotwins in willingness to drive were significant in both monozygotic (MZ) and dizygotic (DZ) male twins but correlations were lower in female twins. Factor and Markovian models were fitted. In males there seem to be both genetic and cultural influences on willingness to drive when drunk. About half the genetic variance seems to be the pleiotropic effects of genes influencing Extraversion. The correlationswith Psychoticism, on the other hand, seem to be largely environmental in origin. The small sample size and lack of proper significance tests mean that these results must be interpreted with caution. 相似文献
73.
A. Gonzalez-Quintela M. Garrido F. Gude J. Campos A. Linneberg S. Lojo C. Vidal 《Clinical and experimental allergy》2008,38(1):152-160
Background Alcohol consumption is associated with increased serum IgE of unknown specificity. Objective To investigate the prevalence of specific IgE to cross‐reactive carbohydrate determinants (CCDs) in adults, and its relation to alcohol consumption. Methods Population‐based survey of 457 adults (218 abstainers, 195 light‐to‐moderate drinkers, 44 heavy drinkers). Specific IgE determinations included a CCD (MUXF3, the N‐glycan of bromelain), pollens (Lolium perenne and Olea europaea), Hymenoptera venoms (Apis mellifera and Vespula spp.), and a mite (Dermatophagoides pteronyssinus). We replicated these studies in an additional sample of alcoholics (n=138). Inhibition assays were performed in selected cases. Results In the general population, 5.6% of individuals (95% confidence interval 3.5–7.6%) showed positive (0.35 kU/L) CCD‐specific IgE. The levels of CCD‐specific IgE were particularly high in heavy drinkers, who also showed a high prevalence of positive IgE to pollens and Hymenoptera venoms, doubling (at least) the prevalence found in alcohol abstainers and light‐to‐moderate drinkers. The presence of IgE to pollens and Hymenoptera venoms was closely correlated with the presence of CCD‐specific IgE. These features were confirmed in the additional sample of alcoholics. Inhibition studies indicated a role of CCD interference in IgE positivity to pollen and Hymenoptera allergens in alcoholics. Conclusions CCD‐specific IgE is prevalent in heavy drinkers, and is associated with positive IgE to pollens and Hymenoptera venoms. Specific IgE results should be interpreted with caution in heavy drinkers. 相似文献
74.
This study of 749 women, aged 45 to 64 years, investigates the psychological, behavioral, and social correlates of alcohol intake. These data from the Framingham Study are uniquely based on a community sample of women, which results in a normative study of drinking behavior in women. Two measures of alcohol intake were utilized in these analyses: (1) the frequency of alcohol intake over 1 week and (2) drinking vs abstaining from alcohol. Among this sample of women, increased socioeconomic status, worrying about aging, and being easily upset were positively associated with frequency of alcohol intake. The rigid attitude scale was the strongest discriminating variable for drinkers vs nondrinkers. Older women were more likely to be nondrinkers compared to younger women, however, among older women, being a homemaker was significantly associated with increased alcohol intake. Contrarily, younger women who were homemakers were more likely to be abstainers than women employed outside the home. As would be expected, cigarette smoking was associated with drinking alcohol.This research is dedicated in fond remembrance to our friend and colleague Joseph Stokes III, M.D. 相似文献
75.
The fact that electrical stimulation of the lateral hypothalamus (LH) can be substituted for the delivery of a food pellet in typical schedule induced polydipsia was established and demonstrated the role of this part of the brain in the mediation of adjunctive behavior. The assumption that Δ9-tetrahydrocannabinol (Δ9-THC) and ethyl alcohol affect behavior because of a differential effect on the same LH mechanism was supported by the following evidence. Relatively small doses of Δ9-THC, 0.25, 0.375, and 0.50 mg/kg, enhanced adjunctive drinking; whereas, larger quantities of 0.625 and 0.75 mg/kg had no appreciable effects. The effect is somewhat specific, as it did not occur with strychnine sulfate, and rate dependent within limits as it was most pronounced in animals with low rates of responding or in animals when responding at a low rate. The effect of rate dependency was also apparent with fixed interval schedules of 2 and 4 min and a multiple schedule of a fixed interval and a signalled timed out period of nonreinforcement. Low rates of responding were enhanced by all doses of Δ9-THC, 1.0, 1.5, 2.0, 2,5, and 3.0 mg/kg, and there was an obvious dose related decrease in high rates. A similar effect was observed with low and high rates of electrical self-stimulation through implanted LH electrodes. The hypothesis that some drugs such as Δ9-THC and ethyl alcohol can enhance the positive feedback in an LH mediated motor control system by the facilitation of the same mechanism which initially generated the behavior was confirmed. Oral self administration of ethyl alcohol in a saccharin sweetened fluid enhanced recovered adjunctive drinking of the solution in quantities which should be sufficient to produce physical dependence if continued for relatively long periods. Recovered adjunctive drinking occurs in animals without food or water deprivation and it is an intense and persistent phenomenon. 相似文献
76.
D Dahiru O Obidoa 《African journal of traditional, complementary, and alternative medicines》2008,5(1):39-45
Chronic alcohol ingestion is known to increase the generation of reactive oxygen species (ROS), thereby leading to liver damage. Antioxidant enzymes act individually or in combination to reduce or counter the effect of these ROS. Chronic administration of alcohol at (40% v/v, 1ml/100g), for 6 weeks showed a significant (p<0.05) elevated levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and total bilirubin (TB). There was also a significant (p<0.05) decreased levels of catalase, glutathione peroxidase, glutathione reductase and superoxide dismutase compared to control rats. Pre-treatment of rats with 200, 400 mg/kg body weight of aqueous leaf extract of Ziziphus mauritiana or 100 mg/kg silymarin resulted in a significant (p<0.05) decreased levels of ALT, AST, ALP, and TB with levels of catalase, glutathione peroxidase, glutathione reductase and superoxide dismutase showing a significant (p<0.05) increase compared to group administered alcohol only. Histopathology of rat liver administered with alcohol only resulted in severe necrosis, mononuclear cell aggregation and fatty degeneration in the central and mid zonal areas which was a characteristic of a damaged liver. Pre-treatment with the aqueous extract of Ziziphus mauritiana or silymarin reduced the morphological changes that are associated with chronic alcohol administration. The presence of tannins, saponins and phenolic compounds observed in the plant extract could be responsible for the observed effects of decreasing the levels of injured tissue marker and lipid peroxidation. 相似文献
77.
William B. Hansen Anne E. Raynor Bonnie H. Wolkenstein 《Journal of behavioral medicine》1991,14(3):205-224
Heavy drinkers, moderate drinkers, light drinkers, and nondrinkers were asked to rate a variety of negative health and social consequences of using alcohol. Subjects made probability ratings for fictional others who were heavy, moderate, or light drinkers or nondrinkers. Subjects also made probability ratings for themselves as hypothetical heavy, moderate, or light drinkers or nondrinkers and for themselves actually. A pattern of perceived personal immunity was found across groups. Subjects rated fictional others and themselves as hypothetical drinkers to be more likely to experience negative consequences than their actual selves. All groups of subjects (heavy, moderate, and light drinkers and abstainers) rated their actual chances of experiencing negative consequences to be approximately equal. In contrast, heavy drinkers saw the effects of drinking for other heavy drinkers as less likely than did subjects who had light or abstinent drinking patterns who rated fictional heavy drinkers. These findings suggest that individuals who drink more tend to deny the potential harm that may result from alcohol consumption. Short-term social consequences were viewed as most likely to occur. Long-term consequences were perceived as least likely to occur.This research was supported in part by grant 1-R01-AA06201 from the National Institute on Alcohol Abuse and Alcoholism. 相似文献
78.
Two cases of liver angiosarcoma among polyvinyl chloride (PVC) extruders of an Italian factory producing PVC bags and other containers 总被引:1,自引:0,他引:1
Two cases are reported of liver angiosarcoma occurring among polyvinyl chloride (PVC) extruders from a small Italian factory producing PVC bags and other containers. The possibility that PVC extrusion carries a risk of liver angiosarcoma is important because of the very large number of people working with extruding, manufacturing and handling PVC, as compared with the number of people working in PVC polymerization and/or VC production. In the past, the level of vinyl chloride (VC) concentration in PVC extrusion workplaces has been thought to be "safe". 相似文献
79.
Finn Jung Katharina Burger Raphaela Staltner Annette Brandt Sebastian Mueller Ina Bergheim 《Nutrients》2021,13(5)
Changes in intestinal microbiome and barrier function are critical in the development of alcohol-related liver disease (ALD). Here, we determined the effects of a one-week alcohol withdrawal on parameters of intestinal barrier function in heavy drinkers with ALD in comparison to healthy non-drinkers (controls). In serum samples of 17 controls (m = 10/f = 7) and 37 age-matched ALD patients (m = 26/f = 11) undergoing a one-week alcohol withdrawal, markers of liver health and intestinal barrier function were assessed. Liver damage, e.g., fibrosis and hepatic steatosis, were assessed using FibroScan. Before alcohol withdrawal, markers of liver damage, lipopolysaccharide binding protein (LBP) and overall TLR4/TLR2 ligands in serum were significantly higher in ALD patients than in controls, whereas intestinal fatty acid binding protein (I-FABP) and zonulin protein concentrations in serum were lower. All parameters, with the exception of LBP, were significantly improved after alcohol withdrawal; however, not to the level of controls. Our data suggest that one-week of abstinence improves markers of intestinal barrier function and liver health in ALD patients. 相似文献
80.
Alcohol and physical inactivity are risk factors for a variety of cancer types. However, alcohol use often co-occurs with physical activity (PA), which could mitigate the cancer-prevention benefits of PA. Alcohol is integrated into the culture of one of the most popular physical activities for adults in the United States (U.S.), golf. This study examined how alcohol use was associated with total PA, golf-specific PA, and motives for golfing in a national sample of golfers in the U.S. Adult golfers (n = 338; 51% male, 81% White, 46 ± 14.4 years) self-reported alcohol use, golfing behavior and motives, and PA. Most (84%) golfers consumed alcohol, averaging 7.91 servings/week. Golf participation, including days/week, holes/week, and practice hours/week, was not associated with alcohol use. Golfers with stronger social motives were 60% more likely to consume alcohol. Weekly walking (incident risk ratio (IRR) = 7.30), moderate-to-vigorous PA (MVPA; IRR = 5.04), and total PA (IRR = 4.14) were associated with more alcohol servings/week. Golfers’ alcohol use may be higher than the general adult population in the U.S. and contributes 775 extra kilocalories/week, a surplus that may offset PA-related energy expenditure and cancer-protective effects. Alcohol use interventions targeting golfers may facilitate weight loss and reduce cancer risk, especially for golfers motivated by social status. 相似文献