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21.
Smoking in Pregnancy and Parenthood: What is the Role of Depression, Anxiety and Nicotine Addiction?
Leona Bull Ronan Burke Siobhan Walsh Emma Whitehead 《Early child development and care》2003,173(2):349-356
This paper presents some of the findings from the Smoking in Pregnancy study of attitudes towards smoking among pregnant women, mothers of young children and their partners in East Surrey. As part of the study, respondents completed a General Health Questionnaire to identify mental health difficulties and, if they were smoking at the time of the study, they also completed the Fagerstrom nicotine addiction test. Eleven female respondents had high scores on the General Health Questionnaire, suggesting symptoms of depression, anxiety and/or social dysfunction for these women. There was no evidence that smokers were suffering from greater mental health difficulties than ex-smokers or non-smokers. However, the General Health Questionnaire scores of smokers were positively associated with their level of nicotine dependence. Furthermore, when General Health Questionnaire scores of all respondents were compared with self-reported health status there was a marked discrepancy suggesting under-reporting of symptoms by women. 相似文献
22.
23.
S. G. Gourlay N. L. Benowitz A. Forbes J. J. McNeil 《European journal of clinical pharmacology》1997,51(5):407-414
Objective: Interindividual variability in plasma concentrations of nicotine and its proximate metabolite, cotinine, is considerable
during smoking and transdermal nicotine treatment, even among individuals taking in nominally similar doses of nicotine. This
report explores the determinants of this variability and the utility of baseline (smoking) plasma concentrations to predict
concentrations during transdermal nicotine treatment.
Methods: Data were analysed from a smoking cessation study (n = 466), and from a pharmacokinetic study (n = 12). Multiple regression models examined the relationships of plasma concentrations to individual characteristics such
as smoking pattern, absorbed dose of nicotine, and pharmacokinetic parameters.
Results: Plasma concentrations of nicotine and cotinine were highly variable in both studies. Indirect estimates of plasma clearance
(baseline plasma concentration divided by cigarettes per day) together with other factors could account for 18 to 33% of the
variability during transdermal nicotine treatment in the smoking cessation study. In contrast, 75 to 99% was accounted for
by direct measurements of plasma clearances and systemic dose of nicotine in the pharmacokinetic study.
Conclusion: Plasma concentrations of nicotine and cotinine during transdermal nicotine treatment are poorly predicted by clinical history
or baseline plasma concentrations. This is a result of inadequate characterisation of highly variable individual pharmacokinetic
parameters and absorbed dose of nicotine. Considering the interindividual variability of plasma nicotine and cotinine concentrations
together with the lack of clinical end-points for transdermal nicotine dosing, it seems logical to investigate the utility
of a therapeutic drug monitoring approach for transdermal nicotine treatment – particularly for high dose regimens (> 22 mg
per 24 hours).
Received: 7 May 1996 / Accepted in revised form: 21 August 1996 相似文献
24.
Nicotine discrimination and self-administration in humans as a function of smoking status 总被引:2,自引:2,他引:0
Nicotine’s discriminative stimulus effects may be critical to understanding reinforcement of tobacco smoking. It is not known
whether regular nicotine exposure produces tolerance or sensitivity to these effects. In this study, male and female smokers
(n = 11) and never-smokers (n = 10) were trained to discriminate 20 μg/kg nicotine by nasal spray from placebo (0) on day 1. On day 2, both groups were
tested on generalization of this discrimination across intermittent presentations of 0, 3, 6, 12, and 20 μg/kg nicotine in
random order. Quantitative and quantal behavioral discrimination tasks, used in previous research, were employed. On day 3,
subjects were instructed to self-administer sprays from the 20 μg/kg nicotine versus 0 bottles in a concurrent-choice procedure.
All but one subject (female smoker) learned reliably to discriminate 20 μg/kg nicotine from placebo (≥ 80% correct) on day 1. Nicotine-appropriate responding on day 2 was attenuated in smokers versus never-smokers at 20 μg/kg
on the quantitative task and at 12 μg/kg on the quantal task, suggesting tolerance. There was no difference in responding
at other doses. Smokers also showed attenuated responses on the subjective measure of “head rush”, which was associated with
discrimination responding in both groups. Nicotine self-administration was significantly greater in smokers versus never-smokers,
who self-administered nicotine below chance levels, and was inversely related to discrimination behavior in never-smokers
but unrelated in smokers. Women smokers showed less change in nicotine-appropriate responding across generalization doses,
reported less confidence in discriminating training doses during acquisition on day 1, and tended to self-administer less
nicotine on day 3. These results indicate that smokers may become tolerant to the discriminative stimulus effects of nicotine,
perhaps promoting increased use.
Received: 1 October 1996/Final version: 28 January 1997 相似文献
25.
Ingela Brådvik Per Wollmer Eva Evander Hildur Lárusdóttir Berith Blom-Bülow Björn Jonson 《European journal of nuclear medicine and molecular imaging》1994,21(11):1218-1222
The rate of clearance from the lungs of inhaled technetium-99m labelled diethylene triamine penta-acetic acid (99mTc-DTPA) is often increased in interstitial lung disease as well as in smoking. In smokers a bi-exponential clearance course of 99mTc-DTPA when measured over 3 h has previously been shown. This study was performed to compare the kinetics of clearance of 99mTc-DTPA, measured for 3 h, in sarcoid patients and healthy smokers. Forty-one never-smoking patients with sarcoidosis and radiological signs of intrathoracic disease were studied. The results were compared with those of 16 healthy current smokers and of 14 healthy never-smokers reported previously. A mono-exponential clearance equation described the clearance in 22 of the sarcoid patients and all normal never-smokers, but with a shorter average tracer half-life in the patients (P<0.05). In 19 patients and all smokers a bi-exponential equation gave a significantly better curve fit. The rate of clearance of the slow component was higher in patients with sarcoidosis than in smokers (P< 0.05). The fraction of the tracer cleared by the fast clearance component was smaller in patients with sarcoidosis than in smokers (P<0.01). Differences in kinetics of clearance of 99mTc-DTPA in sarcoidosis and smoking could thus be demonstrated, suggesting that the abnormal clearance is caused by diverging pathophysiological mechanisms. 相似文献
26.
The use of oral implants opened a wide range of prosthetic treatment possibilities in edentulous patients. Although the reported
success rates of oral implants are high, failures do occur. This paper reviews the current knowledge about the aetiology,
the signs and symptoms and the possible influencing factors of implant failure. Possible causes of implant failure are thought
to be infection of the periimplant tissues, occlusal overload, or a combination of both. Nevertheless, pinpointing one of
these as the aetiological factor in a particular case is difficult and should be handled reluctantly. Although the cause might
seem obvious, influencing factors could play a role as well. Gaining insight into these processes might stimulate the adoption
of preventive action and therefore increase the predictability of the treatment outcome with oral implants.
Received: 4 April 1997 / Accepted: 27 November 1997 相似文献
27.
A panel of 377 healthy adults and 920 COPD patients aged 30–65 years, is annually interviewed (ATS-NHLI health questionnaire) and performs pulmonary function test (PFT), which includes: FVC, FEVI, FEVl/FVC, PEF, FEF50 and FEF75. Baseline data analysis showed a more significant excess in respiratory symptmos (8.8% to 21.4%) and lower PFT (2.4% to 8.0%) among patients occupationally exposed to dust, than among healthy exposed panelists (-0.7% to 7.7% excess symptomatology and -0.3 to 5.8% lower PFT). Among patients a significant correlation between PFT and degree of occupational dust exposure was found. Significantly lower FEVl/FVC and excess in respiratory symptoms (with relative risks of 2.47–16.38) was present in healty smokers vs. non smokers as compared with COPD patients.Corresponding author. 相似文献
28.
A double-blind, placebo controlled trial was undertaken to examine the effect of the 5-HT3 antagonist, ondansetron .25 mg bd on cigarette withdrawal symptoms and on proportion of individuals maintaining continuous abstinence for 4 weeks in a smoking treatment programme. A total of 111 smokers were allocated to active or placebo conditions and began taking their study medication 2 weeks before the quit date. They attended the smokers clinic for weekly group treatment sessions. The results showed no evidence for less severe withdrawal symptoms or improved abstinence rates in the active medication group. They suggest that inhibiting 5-HT3 activity is not an effective method of controlling nicotine withdrawal or helping smokers to stop. 相似文献
29.
慢性阻塞性肺疾病(以下简称慢阻肺)是一种常见的慢性气道异质性疾病。近年来,尽管国内外慢阻肺相关研究不断深入,管理日趋完善,但仍有许多难点亟待解决。2022年9月,《柳叶刀》杂志发布《消除慢阻肺之路》,该文件针对慢阻肺的认识、诊断、评估和个体化治疗等方面提出了新理念并提供临床诊疗指导。本文重点对该文件中慢阻肺的分类、诊断标准及诊断建议、慢阻肺的急性加重和迈向消除慢阻肺5个方面进行介绍和解读,以期为我国临床工作者开展慢阻肺相关研究和管理提供一定的参考及启示。 相似文献
30.
在过去10年中,随着功能脑影像学技术在物质滥用领域的发展,越来越多的研究者运用这些技术以探讨尼古丁成瘾的神经生物学机制。本文主要总结了尼古丁急、慢性暴露下对脑功能影响的神经脑影像学研究进展,证实了尼古丁依赖与中脑边缘犒赏系统、调节注意、记忆、运动以及联想相关脑环路之间的相关性。这些研究发现将为揭示尼古丁依赖的神经生物学机制提供更多的证据支持,进一步促进今后戒烟治疗的发展。 相似文献