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71.
The objective of this study was to assess the association betweenalcohol drinking before and during pregnancy and the risk ofspontaneous abortion using data from a case-control study conductedin Milan, Italy. A total of 462 women (median age 30 years)were admitted for spontaneous abortion (within the 12th weekof gestation) to a network of obstetrics departments in thegreater Milan area. Of these, 148 (32%) were between the fourthand the eighth week of gestation and 314 (68%) between the ninthand the 12th week. A control group was made up of 814 women(median age 29 years) who gave birth at term (>37 weeks gestation)to healthy infants (Apgar 5th minute 8, weight 3000 g) on randomlyselected days at the same hospitals where cases had been identified.A total of 212 cases (46%) and 355 controls (47%) reported alcoholdrinking before conception. Considering non-drinkers as thereference category, the relative risks (RR) of spontaneous abortionwere 1.2 (95% confidence interval (CI), 0.9–1.6] and 0.8(95% CI, 0.6–1.1), respectively, in drinkers of one toseven and more than seven drinks per week before conception.No association emerged between the duration of alcohol drinkingand the risk of spontaneous abortion. A total of 166 cases (35.9%)and 263 (32.3%) controls reported any alcohol drinking duringthe first trimester of pregnancy. The corresponding relativerisk was 1.1 (95% CI, 0.9–1.4) and no relationship emergedbetween the number of drinks per week and the risk of abortion.Likewise, maternal wine and beer drinking in the first trimesterof pregnancy was not associated with the risk of spontaneousabortion. Evidence available from this and previous studies,although partially controversial, indicates that moderate (oneor two drinks per day) alcohol consumption does not increasemarkedly the risk of miscarriage.  相似文献   
72.
Institute of Therapy, Siberian Branch, Academy of Medical Sciences of the USSR, Novosibirsk. All-Union Preventive Medicine Research Center, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR Yu. P. Nikitin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 110, No. 12, pp. 611–613, December, 1990.  相似文献   
73.
This study examined alcohol use among seventh graders in relation to life events, daily hassles, the supportive quality of the family environment, coping, and anxiety. Four hundred twenty-five students participated, 228 girls and 197 boys. Stepwise regression and discriminant function analyses indicated that the students reported more alcohol use if they also reported more life events, more daily hassles, and more conflict in the family. A stress-buffering effect of low family conflict on life events could not be substantiated for extent of alcohol use. The results are discussed in the context of the developmental transitions of adolescence.  相似文献   
74.
Novel pH-sensitive hydrogels were developed as suitable candidates for carriers in bioMEMS devices as well as for oral delivery of therapeutic peptides and proteins due to their ability to respond to environmental pH change. Macromonomers containing various PEG molecular weights were synthesized and used to prepare P(MAA-g-EG) hydrogels were by photopolymerization. P(MAA-g-EG) hydrogels showed a drastic change of the equilibrium swelling ratio between pH 2.2 and 7.0. At pH 7.0, hydrogels with PEGMA2000 exhibited higher swelling ratio than hydrogels with PEGMA1000. For both hydrogels with PEGMA1000 and PEGMA2000, the swelling mechanism became more relaxation-controled as the environmental pH changed from 2.2 to 7.0 due to the ionization of the functional groups in polymer networks at high pH. In vitro release studies of insulin were conducted. P(MAA-g-EG) hydrogels exhibited drastic increase of insulin release as the pH of the medium was changed from acidic to basic. Insulin release from P(MAA-g-EG) hydrogels with PEGMA2000 was slower than from hydrogels with PEGMA1000 at both low and high pH. These results were used to design and improve protein release behavior from these carriers.  相似文献   
75.
In the freely moving rat, the kinetics of Ca2+ ion activity were determined at circumscribed sites in the hippocampus, which was perfused with ethanol, tertiary-butyl alcohol or acetaldehyde. Initially, a region in CA1 or other cell field of the dorsal hippocampus was prelabelled by microinjection of45Ca2+ through a permanently implanted guide tube. Then the tip of a concentric push-pull cannula assembly was lowered through the guide tube to the labelled site, and an isotonic artificial cerebrospinal fluid was repeatedly perfused at a rate of 25 μ1/min. Each perfusion was timed for 5.0min with a 5.0 min interval between each. Once the washout curve of45Ca2+ activity had begun to approach its asymptote, ordinarily in the midpoint of a series of perfusions, an isotonic solution of ethanol (188–942 mM), tertiary-butyl alcohol (12–580 mM) or acetaldehyde (10–98 mM) was added to the fourth perfusate. Thereafter, the hippocampal site was again perfused with the normal cerebrospinal fluid for the remainder of the experiment. Although the lowest concentration of ethanol exerted no effect on45Ca2+ ion activity, an intermediate concentration caused mixed effects in either enhancing or suppressing the efflux into the perfusate of this cation. The highest concentration of ethanol produced in most experiments an initial suppression in Ca2+ ion efflux which was followed frequently by an elevation in the release of45Ca2+. Similar changes in Ca2+ ion activity were produced by tertiary-butyl alcohol, but the magnitude of its effect was generally less than that of ethanol, suggesting that its effect on brain tissue differs from that of ethanol. Acetaldehyde evoked an intense and concentration-dependent enhancement of Ca2+ ion efflux from the perfused tissue at all of the sites in the hippocampus examined.These results suggest that in the unrestrained rat ethanol could unbind Ca2+ ions from hippocampal membranes or retard their uptake into cells of the hippocampus. The dual excitatory and inhibitory effect of ethanol on Ca2+ ion activity corresponds to the electrophysiological effects of this alcohol and could alter neurotransmitter release from neurons in this subcortical structure. The mechanism of action of acetaldehyde is envisaged to be due to its affinity to membrane sulfhydryl groups which alters protein conformation and thus interferes with both Ca2+channels and Ca2+ binding properties.  相似文献   
76.
The purpose of this study was to determine the degree to which the use of tobacco, alcohol, and marijuana by young adolescents can be described using a common theoretical model. Structural models were created in which psychosocial variables hierarchically predicted the use of each substance. The fit of a model in which paths from predictor variables were constrained to be equal was not inferior in any meaningful way to that of a model in which all path coefficients were freely estimated, thus suggesting that use of tobacco, alcohol, and marijuana by young adolescents may be considered to be a unitary phenomenon. A simplified model, in which these substances were combined into a single latent variable, showed a good fit. The results of these analyses suggest that it may be beneficial to consider adolescent substance use to be a unitary phenomenon.This research was supported by National Institute on Drug Abuse Grant 1-R18-DA-003406.  相似文献   
77.
A set of calibrated lickometers provides continuous, quantitative monitoring of fluid consumption. It has been used in our laboratory at four levels of temporal resolution: 24 hr, 1 hr, 6 min, and for counting of individual licks. Convenient features are mounting of the licking tube-bottle assembly on the cage top (which permits the use of disposable plastic cages with litter) and automated collection of data with microcomputers.  相似文献   
78.
A/J and C57BL/6J mice behave differently in tests for alcohol preference, open-field activity, defecation in the open field, cricket attacking, and rope climbing. Chimeric mice, i.e., mice containing both A/J cells and C57BL/6J cells, were constructed and tested for these behaviors. Patterns of behavior among A/JC57BL/6J chimeras are such as to suggest that none of these behavior differences is controlled by a single cell or clone and that the same cell population that gives rise to the strain difference in alcohol preference also gives rise to the differences in open-field activity and defecation, while separate cell populations control cricket killing and rope climbing.This research was supported by Research Grants AA 00388 and HD 03015 to M. N. N. and MH 18996 to K. B. Computing assistance was obtained from the Health Sciences Computing Facility, UCLA, supported by NIH Special Research Resources Grant RR-3.  相似文献   
79.
院外纳曲酮治疗酒精依赖的疗效观察   总被引:3,自引:0,他引:3  
目的 :评估纳曲酮院外治疗酒依赖的临床疗效。方法 :采用随机对照的方法 ,分别对纳曲酮组和安慰剂组各 2 3例和 2 2例 ,作总疗程 12周的临床观察。结果 :纳曲酮显著降低病人对酒精的渴求程度 ,其疗后 4、 8、 12周的保持率分别为 91 3 %、 77 9%、 73 3 % ,明显高于安慰剂。纳曲酮的副作用与安慰剂相当 ,其主要副作用为轻度的恶心、厌食、头晕。结论 :纳曲酮是一种安全有效的治疗酒依赖的药物  相似文献   
80.
In the present study we prepared macroporous polyvinyl alcohol beads. A series of bilirubin adsorbents were generated by immobilization of eight amine agents to the beads as ligands. The adsorption of bilirubin was evaluated by in vitro static and dynamic adsorption tests. The results show that these adsorbents have excellent adsorption efficiency and capacity. Among the eight ligands, trimethylamine (TMA), triethylamine (TEA) and 1,6- hexanediamine(HDA) showed the highest adsorption capacity. The adsorption equilibrium can be achieved in half an hour, and the adsorption percentage of bilirubin was up to 80%. Static electricity and hydrophobic interaction played the main role in bilirubin adsorption, and the adsorption was found to match the monolayer model. The excellent adsorption of these adsorbents indicates their potential in clinical treatment.  相似文献   
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