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11.
Observations in humans suggest that the initial use of tobacco occurs in close temporal proximity to experimentation with
alcohol. There have been relatively few research reports, however, examining possible interactions between these two agents.
The present experiments examined the effect of nicotine exposure on the acquisition of ethanol drinking behavior in a limited
access procedure. In experiment 1, rats were presented with 1-h access to ethanol solutions of increasing concentration for
a period of 20 days. Subcutaneous injections of nicotine (0.6 or 1.2 mg/kg salt) or vehicle were administered 30 min prior
to each ethanol presentation. Experiment 2 used a similar method, but rats were presented with water along with ethanol during
the 1-h test session. Mecamylamine, a nicotinic receptor antagonist, was administered 30 min prior to the nicotine treatment.
Nicotine was seen to produce a dose-dependent increase in ethanol drinking behavior which commenced at the 5% ethanol concentration
and continued at 8% and again at 10%. In the second experiment, mecamylamine was observed to block completely the nicotine-induced
increase in ethanol drinking behavior. The findings suggest that exposure to nicotine can facilitate the acquisition of ethanol
drinking behavior in naive rats and that this effect is mediated by nicotine’s interaction at the nicotinic-cholinergic receptor.
Received: 11 June 1998 / Final version: 1 October 1998 相似文献
12.
Griffith M. E.; Lovegrove J. U.; Gaskin G.; Whitehouse D. B.; Pusey C. D. 《Nephrology, dialysis, transplantation》1996,11(3):438-443
BACKGROUND.: Antineutrophil cytoplasmic antibodies (ANCA) in vasculitis haveeither cANCA or pANCA patterns as defined by immunofluorescence.The target autoantigen of cANCA is usually proteinase 3 (PR3),whereas that of pANCA is usually myeloperoxidase (MPO). Alpha-1-antitrypsin(1AT) is the major physiological inhibitor of PR3, while MPOis an inhibitor of 1AT. METHODS.: To determine whether there was an association between ANCA positivevasculitis, ANCA pattern, and 1AT deficiency alleles, we studied1AT phenotypes of 99 cANCA and 99 pANCA positive vasculitispatients by isoelectric focusing and immunoblotting, and comparedthem with 2310 controls from the same geographical area. RESULTS.: C-ANCA patients showed an increased frequency of the Z allele(0.055 versus 0.018 in controls), conferring a relative riskof 3. They showed no increase in frequency of the S allele.P-ANCA patients showed an increased frequency of the S allele(0.091 versus 0.046 in controls) conferring a relative riskof 2. The frequency of the Z allele also appeared to be increased(0.030 versus 0.018 in controls), but this was not statisticallysignificant. CONCLUSIONS.: These findings demonstrate an association between ANCA-positivevasculitis and deficiency phenotypes of 1AT, and suggest a rolefor 1AT in the development of systemic vasculitis. 相似文献
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Darrell J Gaskin Kevin P Weinfurt Liana D Castel Venita DePuy Yun Li Andrew Balshem Al Benson Caroline B Burnett Sandra Corbett John Marshall Elyse Slater Daniel P Sulmasy David Van Echo Neal J Meropol Kevin A Schulman 《Medical decision making》2004,24(6):614-624
OBJECTIVE: The authors sought to empirically test whether relative health stock, a measure of patients' sense of loss in their health due to illness, influences the treatment decisions of patients facing life-threatening conditions. Specifically, they estimated the effect of relative health stock on advanced cancer patients' decisions to participate in phase I clinical trials. METHOD: A multicenter study was conducted to survey 328 advanced cancer patients who were offered the opportunity to participate in phase I trials. The authors asked patients to estimate the probabilities of therapeutic benefits and toxicity, their relative health stock, risk preference, and the importance of quality of life. RESULTS: Controlling for health-related quality of life, an increase in relative health stock by 10 percentage points reduced the odds of choosing to participate in a phase I trial by 16% (odds ratio = 0.84, 95% confidence interval = 0.72, 0.97). CONCLUSION: Relative health stock affects advanced cancer patients' treatment decisions. 相似文献
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KA Hodgkinson SP Connors N Merner A Haywood T‐L Young WJ McKenna B Gallagher F Curtis AS Bassett PS Parfrey 《Clinical genetics》2013,83(4):321-331
To determine the phenotype and natural history of a founder genetic subtype of autosomal dominant arrhythmogenic right ventricular cardiomyopathy (ARVC) caused by a p.S358L mutation in TMEM43. The age of onset of cardiac symptoms, clinical events and test abnormalities were studied in 412 subjects (258 affected and 154 unaffected), all of which occurred in affected males significantly earlier and more often than unaffected males. Affected males were hospitalized four times more often than affected females (p ≤ 0.0001) and died younger (p ≤ 0.001). The temporal sequence from symptoms onset to death was prolonged in affected females by 1–2 decades. The most prevalent electrocardiogram (ECG) manifestation was poor R wave progression (PRWP), with affected males twice as likely to develop PRWP as affected females (p ≤ 0.05). Left ventricular enlargement (LVE) occurred in 43% of affected subjects, with 11% fulfilling criteria for dilated cardiomyopathy. Ventricular ectopy on Holter monitor was common and occurred early: the most diagnostically useful clinical test. No symptom or test could rule out diagnosis. This ARVC subtype is a sex‐influenced lethal arrhythmogenic cardiomyopathy, with a unique ECG finding, LV dilatation, heart failure and early death, where molecular pre‐symptomatic diagnosis has the greatest clinical utility. 相似文献
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