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11.
羊耳菊水提取物体外抑菌活性研究   总被引:3,自引:0,他引:3  
目的 探讨羊耳菊不同器官水提取物的体外抑菌活性.方法 以金黄色葡萄球菌、铜绿假单胞菌、白色念珠菌等10种微生物为试验菌株,采用药敏纸片扩散法、试管二倍稀释法,对羊耳菊水提取物进行抑菌试验.结果 羊耳菊全株各器官都具有较强的抑菌作用,其中根对10种供试菌种都有抑制作用,抑制范围最广;茎对9种供试菌种有抑制作用,叶对8种供试菌种有抑制作用.羊耳菊各器官对金黄色葡萄球菌与铜绿假单胞菌的抑制作用最强.羊耳菊根、茎、叶对金黄色葡萄球菌的MIC值分别为15.63,62.5,62.5 mg/ml,而其抑菌圈直径分别为14.3,13.8,13.5 mm;羊耳菊根,茎,叶对铜绿假单胞菌的MIC值分别为15.63,31.25,62.5 mg/ml,其抑菌圈直径分别为15.8,15.5,14.0 mm.结论 羊耳菊水提取物体外试验证实了该民间药物具有抗菌活性,也表明了羊耳菊是一种有开发潜力的新抗菌药物资源.  相似文献   
12.
Longitudinal research studies focused on alcohol use initiation in adolescence were reviewed to determine which variables function as antecedent predictors or risk factors. Only studies that focused on time-1 abstainers were included. Classes of risk factors examined include sociodemographic, family, peer, personality, and behavioral variables. The most consistent antecedent risk factors for starting to drink in adolescence were parental and peer approval and models for drinking and drug use as well as adolescents’ own prior involvement in delinquent behavior. There was little evidence for gender differences in risk factors for alcohol use initiation. Secondary analyses of existing longitudinal data sets are encouraged to examine whether there are ethnic/racial differences in the risk factors for starting to drink and to establish those factors that serve a protective or buffering function, delaying onset of alcohol use in adolescence.  相似文献   
13.
用薄层聚丙烯酰胺凝胶电泳方法分析118头人繁殖恒河猴血清四种蛋白质和同工酶遗传基因位点的多态性,结果表明,除醇脱氢酶(ADH)为单态外,其余三个基因位点均表现多态,前清蛋白(PA)可分为AA、AB、AC、AD和BB、CC,EE七种表型,各基因的频率为A 0.85,B 0.072,C 0.042,D 0.009,E 0.034转铁蛋白(Tf)可分为CC、DD、EE、FFGG、CD、CE、CG、CH、DE、DF、DG、DH、EF、EG、EH、FG十七种表型,墓因频率为C 0.064,D 0.380,E 0.188,F 0.111,G 0.244,H 0.014,苹果酸脱氢酶(MDH)可分MDH)1-1和MDH2-1两种表型,基因频率为MDH~10.958和MDH~20.042。  相似文献   
14.
Current knowledge about alcohol and marital functioning is limited by restrictive sample selection, inattention to the literature on individual-based alcoholic subtypes, and lack of research linking individual differences among alcoholics to marital functioning. The present study was designed to study marital functioning of alcoholics in light of current alcohol typologies. Subjects were part of a larger study on conjoint treatment of alcoholic males and their female partners. Four typologies—including Type 1/2, In-Home/Out-of-home, SteadyIEpisodic, and EarlyILate Onset—were tested for replicability and discriminant validity before linking them to marital functioning. Discriminant validity was found only for the Early (59%)-versus Late (41 %)-Onset typology; thus, further analyses linked only this typology with marital functioning. At baseline, Early-Onset couples reported more marital instability, and the females in these couples were more distressed. During treatment, Early-Onset couples reported higher daily marital satisfaction than Late-Onset couples. Regardless of age of onset, males reported higher marital satisfaction than their spouses during treatment, but their satisfaction did not increase during treatment. Female partners' marital satisfaction increased during treatment. Female partners of Late-Onset males reported particularly low marital satisfaction during treatment. Parsing the sample according to the early-/late-onset typology yielded different predictors of marital satisfaction for males and females within each subtype. For female partners of Early-Onset alcoholics, psychological distress unrelated to her pattner's drinking severity was most associated with her own marital satisfaction, whereas marital adjustment of female partners of Late-Onset alcoholics was most associated with the male's level of perceptual accuracy regarding her needs. This pattern was reversed for the males; marital adjustment of Early-Onset alcoholics was most associated with his partner's perceptual accuracy of his needs, whereas marital functioning of Late-Onset alcoholics was best accounted for by his own psychological distress.  相似文献   
15.
Ethanol-induced fatty liver in rats was attenuated by repeated running exercise, and the protective effect of exercise was associated with the synergistic expression of heat shock proteins (HSP72). Rats were placed in four groups of six. The two ethanol-fed groups of rats received a liquid diet (Lieber-DeCarli formulation) in which 36% of the calories were derived from ethanol. One group remained sedentary (S/E), whereas the other was trained to run on a rodent treadmill at a speed of 27 m/min, 1 hr/day, 5 days/week, for 7 weeks (R/E). Two other groups–one exercised as previously mentioned (R/C) and one sedentary (S/C)–received control-liquid diets in which the ethanol was isocalorically substituted with a dextran/maltose mixture. The degree of fatty infiltration in liver sections stained with hematoxylin and eosin was graded on a 0–4 scale and the data analyzed by ANOVA on ranks. Ethanol significantly induced fatty infiltration in the S/E group, whereas fatty infiltration in the livers of the R/E group was not different from the S/C group. Electrophoresis and Western blotting of liver homogenates demonstrated that HSP72 was not expressed in either the S/C or S/E groups and was only slightly expressed in the R/C group. The combination of exercise and ethanol, however, resulted in an elevated expression of HSP72 in the R/E group. The content of HSP73 was unaffected by any treatment.  相似文献   
16.
A series of experiments evaluated the determinants of preference for mixtures of ethanol plus sucrose relative to sucrose in rats. One dipper served 10% ethanol mixed with 10% sucrose, and the second dipper served 10% sucrose. Lever presses operated each dipper according to a variable-interval 5-s schedule. In three experiments the subjects were given pre-session meals of sucrose (2.5–20 ml) or sucrose (20 ml) plus chow (5 or 10 g). Pre-session meals decreased responding maintained by sucrose but not responding maintained by ethanol mixture. In two experiments body weight was varied from 85% to 125% of the initial free-feeding values. Increases in body weight, like pre-session meals, decreased responding reinforced by sucrose, but typically did not decrease responding reinforced by ethanol mixture. Throughout most of the study, ethanol consumption remained at about 1.25 ml per half hour session (3–4 g/kg per 30 min). For example, pre-session access to ethanol mixture decreased within-session ethanol consumption, but total consumption, counting both sources, remained about 1.25 ml/session. The within-session patterns of responding also differed. Responding reinforced by ethanol mix decreased as a function of ethanol consumption, whereas responding reinforced by sucrose was relatively constant throughout the session. The simplest explanation of the results is that ethanol's pharmacological consequences regulated preference.  相似文献   
17.
High-Risk Drinking across the Transition from High School to College   总被引:4,自引:0,他引:4  
Alcohol use and related problems were studied from the senior year in high school to the first autumn in college for 366 heavy drinking students. Four risk factors-subject sex, family history of drinking problems, prior conduct problems, and type of college residence-were evaluated as predictors of: (1) differential changes in drinking rates, (2) differential changes in alcohol-related problems, and (3) alcohol dependence symptoms during the first college term. Results suggest that both dispositional and environmental factors are associated with changes in drinking rates and the existence of dependence symptoms. Increases in the frequency of drinking were specifically and strongly associated with residence in a fraternity (men) or sorority (women). Three risk factors were associated with increased quantity of drinking: male gender, residence in a fraternity or sorority, and a history of conduct problems. Prior conduct problems were also consistently associated with dependence symptoms during the first term in college. A family history of alcohol problems was not consistently related to changes in use rates or problems, although some analyses suggest interactive effects. Early interventions on college campuses should target individuals using additive risk profiles.  相似文献   
18.
A retrospective study compared the course of alcohol withdrawal, including delirium tremens, in women and men hospitalized in the Nowowiejski Hospital in Warsaw from 1973 to 1987. Medical records pertaining to 1179 patients were analyzed; 13.8% of these patients were women and 86.2% were men. The study showed that women began intensive alcohol drinking later than men ( p < 0.0001), but the period between the onset of alcohol abuse and the first occurrence of alcohol withdrawal was shorter in women than in men ( p < 0.0001). In the period of heavy drinking before hospitalization, women consumed significantly less alcohol then men ( p < 0.0001); moreover, women drank nonbeverage alcohol less frequently than men ( p < 0.05). Women were hospitalized substantially longer than men ( p < 0.0001), whereas the duration of alcohol withdrawal symptoms at the time of hospitalization was comparable in both groups. Withdrawal seizures were significantly more frequent among men than among women ( p < 0.001). Significant differences in the patients'somatic conditions were not noted between the groups, with the exception of anemia and decreased potassium concentration, which were more frequently observed in women (both p < 0.0001), and of increased concentration of ALT and hypoproteinemia, which were more frequent in men (respectively, p < 0.05 and p < 0.01). Co-existing personality disorders, depressive disorders, and anxiety disorders—as well as abuse of benzodiazepines and barbiturates—were more frequently observed in women ( p < 0.0001). The period between the first hospitalization due to alcohol withdrawal and the time of death was significantly shorter in men than in women ( p < 0.05). The results point to differences in the conditions and the course of alcohol dependence and alcohol withdrawal between women and men.  相似文献   
19.
Alcohol consumption during pregnancy is teratogenic and induces severe alterations in hepatocytes. In the hepatocyte peroxisomal system, ethanol is converted in the presence of H2O2 to acetaldehyde and water. Therefore, peroxisomal catalase also acts as an antioxidant defence mechanism by removing H2O2 and preventing the formation of hydroxyl radicals in the cell. Alterations in peroxisomal catalase after pre- and pre+postnatal alcohol exposure were investigated in the rat. The effect of pre- and postnatal exposure to ethanol on hepatocyte subpopulations was analysed in isolated hepatocytes originating from periportal, intermediate and perivenous zones. Analysis of catalase revealed that the total activity and content of this enzyme were higher in 12-day-old cells than in cells from newborns and that this increment was more pronounced in treated cells. In controls, the amount of peroxisomal catalase increased mainly in periportal cells, whereas alcohol exposure induced a significant increase in the catalase of perivenous hepatocytes. We conclude that pre- and postnatal alcohol exposure mainly affects the perivenous hepatocyte peroxisomes and that the increase in peroxisomal catalase could constitute a defence mechanism against free radical generation induced by alcohol exposure during the perinatal period.  相似文献   
20.
 Within a number of physiological preparations, the effects of alcohol and cocaine in combination are reported to be greater than the effects of either drug given alone. Little has been reported, however, on the behavioral effects of the interaction. The present study investigated this issue by assessing the effects of cocaine and alcohol (alone and in combination) on schedule-controlled responding. Specifically, rats were trained to respond on an FR20 schedule for a water reinforcer. They were then administered cumulative doses of cocaine or alcohol. Following this, subjects were administered ineffective doses of alcohol prior to further dose-response assessments with cocaine and with ineffective doses of cocaine prior to further dose-response assessments with alcohol. Cocaine and alcohol alone produced dose-related decreases in responding. Furthermore, the dose-response function for cocaine was shifted to the left by alcohol and the dose-response function for alcohol was shifted to the left by cocaine. An isobolographic analysis revealed that the interaction between cocaine and alcohol was additive in nature. The possible bases for the interaction (e.g., changes in cocaine pharmacokinetics by alcohol and the formation of cocaethylene following co-administration of cocaine and alcohol) were discussed. Received: 22 February 1996 / Final version: 23 August 1996  相似文献   
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