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21.
Results are presented of a follow-up study in which a representative sample of 608 Prague women aged 20–49 years in 1987 at first interview was re-interviewed in 1992 3 years after the revolution that ended the 41 years of the Communist era in Czechoslovakia. The average yearly consumption of alcohol in the followed-up female sample increased between 1987–92 from a reported 3.6 litres to 4.8 litres. The percentage of heavier drinkers (with average daily consumption of over 20 g alcohol) increased from 7.2% to 14.0%. The women expressed increased tolerance of drunkenness in their attitudes to drinking. The consumption increase was mainly due to increased drinking frequency of spirits and to increased quantity of beer consumed per occasion. The consumption increase was largest in women working as free-lance and the newly emerging self-employed women; economically inactive women did not increase their consumption. Women who reported a positive impact of the socio-political changes on their personal lives and an expansion of social contacts also reported larger than average consumption increases. A coincidence of stressful, possibly self-inflicted, life events and increased alcohol use was observed and interpreted as probably a two-way influence.  相似文献   
22.
目的 :研究硝苯吡啶以及硝苯吡啶与格列本脲合用对空腹大鼠和肾上腺素诱发高血糖大鼠血糖水平的影响。方法 :本实验采用葡萄糖氧化酶法测定血糖含量。结果 :硝苯吡啶 2 .5mg/kgig使空腹大鼠血糖水平显著升高(P <0 .0 1 ) ,并加重肾上腺素诱发的高血糖反应。而硝苯吡啶与降糖药格列本脲 0 .9mg/kg合用时不影响空腹大鼠的血糖水平 ,硝苯吡啶对肾上腺素诱发高血糖大鼠灌胃格列本脲后的降血糖作用亦无明显影响。结论 :尽管硝苯吡啶对空腹大鼠以及肾上腺素诱发高血糖大鼠有显著升高血糖的作用 ,但对格列本脲的降血糖作用无明显不良影响  相似文献   
23.
Stearidonic acid (SDA; C18:4n-3) has been suggested as an alternative to fish oil (FO) for delivering health benefits of C ≥ 20 long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA). Echium oil (EO) represents a non-genetically-modified source of SDA available commercially. This study compared EO and FO in relation to alterations in plasma and tissue fatty acids, and for their ability to afford protection against ischemia-induced cardiac arrhythmia and ventricular fibrillation (VF). Rats were fed (12 weeks) diets supplemented with either EO or FO at three dose levels (1, 3 and 5% w/w; n = 18 per group). EO failed to influence C22:6n-3 (DHA) but increased C22:5n-3 (DPA) in tissues dose-dependently, especially in heart tissue. Conversely, DHA in hearts of FO rats showed dose-related elevation; 14.8%–24.1% of total fatty acids. Kidney showed resistance for incorporation of LC n-3 PUFA. Overall, FO provided greater cardioprotection than EO. At the highest dose level, FO rats displayed lower (p < 0.05) episodes of VF% (29% vs. 73%) and duration (22.7 ± 12.0 vs. 75.8 ± 17.1 s) than the EO group but at 3% EO was comparable to FO. We conclude that there is no endogenous conversion of SDA to DHA, and that DPA may be associated with limited cardiac benefit.  相似文献   
24.
交沙霉素在中国汉族、维吾尔族及哈萨克族中的药代动力学比较李国昌陈春雁杨明义(新疆石河子医学院第一附属医院药剂科,石河子832008;石河子农学院医院,石河子832003)为探讨交沙霉素(josamycin)在不同民族正常人体内过程,我们用相同的受...  相似文献   
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26.
Specific interactions between the 72-amino acid nucleocapsid protein NCp7 of the human immunodeficiency virus, type 1 and the genomic RNA are essential for virus replication. Studies on the mechanism of action of NCp7 require a direct visualization of its complexes with nucleic acids and the determination of binding affinities. To facilitate these investigations, fluorescent NCp7 derivatives were developed by introduction in the NCp7 sequence of a non-natural amino acid, (S)-β-(9-acridinyl)alanine (Aca) obtained by a chiral synthetic method. Three fluorescent NCp7 derivatives were obtained by introducing this amino acid at different positions. As shown by NMR, the three-dimensional structure of NCp7 is not altered by introduction of Aca. The fluorescent peptides were found to be as potent as their precursors in interacting with nucleic acids and in promoting HIV-1 genomic RNA dimerization. Moreover, because of their fluorescent properties, these NCp7s can be used at submicromolar concentrations to directly visualize and quantify protein-nucleic acid interactions in solution or after gel electrophoresis. This could facilitate the development of new antiviral agents aimed at inhibiting the functions of NCp7 and studies on the intracellular traffic of NCp7 within the preintegration complex.  相似文献   
27.
The paper reports results of an analysis based on face-to-face interviews with two samples of Prague women aged 20-49: (1) a probabilistic sample (h = 718) of the Prague female population; and (2) a sample of 152 inpatients treated for substance dependence/abuse. Of the inpatients, 79% were diagnosed as alcohol dependent only, 15% as both alcohol dependent and drug dependent/abusers, 6% as drug dependent only. With very few exceptions, those with drug problems among the inpatients abused analgesics, hypnotics, or anxiolytics. With data obtained from the general population sample, two-stage hierarchical logistic regression was run with each of the eleven differently defined substance uses as dependent variables. Four demographic variables were entered as predictors into the regression equations in the first stage. From the seven potential risk factors of substance use statistically significant predictors were entered stepwise in stage two. The major result of the study is the specificity of the pattern of predictors related to each of the eleven considered substance uses. It is also found that in the general population the use of a particular substance is generally uncorrelated with the use of other substances. Alcohol use (even heavy alcohol use) has no relation to smoking, to the use of analgesics, hypnotics, anxiolytics-and is connected with a specific pattern of predictors.  相似文献   
28.
The role of membrane lipid composition on the modulation of ouabain sensitivity of cardiac Na+/K+-ATPase has been studied in vitro using several animal species. The animals can be grouped as ouabain-sensitive and ouabain-insensitive species. Ouabain-sensitive species (I50; 0.5-2.2 microM) include sheep, marmoset, pig and the guinea pig, whilst rat and mouse form the ouabain-insensitive group (I50; 100-105 microM). Although no species variation in the distribution of major phospholipid classes was observed, significant differences were apparent in the proportions of certain saturated and unsaturated phospholipid fatty acids. Thus, there was a marked increase in the relative proportion of docosahexaenoic (22:6, omega-3) acid in the Na+/K+-ATPase preparations from the rat and mouse compared to ouabain-sensitive species. Despite these differences, all animals had similar proportions of total saturated (sigma SAT) and total unsaturated (sigma Unsat) fatty acids. On the other hand, a good correlation between the unsaturation index of membrane lipids and I50 value for ouabain was observed. It is proposed that acyl chain characteristics (unsaturation and/or chain length) rather than the head group of the phospholipid molecule play a major role in the modulation of Na+/K+-ATPase to inhibition by ouabain.  相似文献   
29.
We have shown independently that dietary fiber and n−3 fatty acids can affect gut function. This study investigated the interactive effects of resistant starch (RS) (as high amylose maize starch [HAMS]) and tuna fish oil on ileal contractility. Four-week-old male Sprague Dawley rats were fed 4 diets that contained 100 g/kg fat as sunflower oil or tuna fish oil, with 10% fiber supplied as α -cellulose or HAMS for 6 weeks. Fish oil feeding led to higher ileal n-3 fatty acid levels (mainly as DHA) and higher agonist-induced maximal contractility with an RS effect noted for carbachol. HAMS-containing diets resulted in lower colonic pH and higher total short-chain fatty acids (SCFA), but not for butyrate with fish oil. Low prostanoid responses in young rats were enhanced by fish oil independent of RS. The order of muscarinic receptor subtype responses were different compared to older rats; fish oil feeding altered the sensitivity of the M1 receptor subtype. Although little interactive effects were demonstrated, these data suggest developmental changes in ileal receptor systems with independent effects of RS and fish oil on some bowel properties in juvenile rats.  相似文献   
30.
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