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1.
The authors present results of a randomized clinical trial of the efficacy of extended treatment with bupropion SR in producing longer term cigarette smoking cessation. Adult smokers (N = 362) received open-label treatment (11 weeks) that combined relapse prevention training, bupropion SR, and nicotine patch followed by extended treatment (14 weeks) with bupropion SR or matching placebo. Abstinence percentages were relatively high (week 11: 52%; week 25: bupropion, 42%; placebo, 38%; week 52: bupropion, 33%; placebo, 34%), but bupropion SR did not surpass placebo. Gender and baseline craving level were identified as significant, independent moderators of treatment response. Men were more likely to abstain than women (week 11: 59% vs. 43%, p = .001; week 25: 48% vs. 31%, p = .001; week 52: 39% vs. 27%, p = .01). Because most smokers suffer relapse with any current cessation treatment, the comparatively high abstinence percentages achieved in this trial are of interest. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
Stability against light soaking was studied for amorphous silicon (a-Si:H) solar cells using three different i-layers; (a) device-quality a-Si:H (standard a-Si:H) with bandgap of 1.75 eV, (b) narrow bandgap (1.55 eV) a-Si:H fabricated by Ar* chemical annealing and (c) a-Si:H(Cl) fabricated from SiH2Cl2. Both the narrow bandgap a-Si:H and the a-Si:H(Cl) solar cells showed much improved stability than that of the standard a-Si:H solar cells: e.g., fill factor of the narrow bandgap a-Si:H cell only slightly decreased from 56% to 53%, while that of the standard a-Si:H cell degraded from 62% to 51%. In addition, mobility–lifetime products of the a-Si:H(Cl) cell also exhibited improved stability than that of the standard a-Si:H solar cell.  相似文献   
3.
Narrow band gap (1.5 eV) hydrogenated amorphous silicon (a-Si:H) were fabricated by a chemical annealing technique using noble gases (Ar, He, Ne). Although hydrogen content in the film was reduced to 1 atm% and band gap was decreased to 1.52 eV, high photoconductivity and large mobility–lifetime products were maintained and no marked changes in the short-range structure was found. Using these narrow band gap a-Si:H for photoactive layer in n-i-p solar cells, reasonable photovoltaic performances were obtained, i.e., open-circuit voltage of 0.71 V and fill factor of 57%. Also enhanced red response was observed with the 1.58 eV band gap i-layer solar cell prepared on textured substrate.  相似文献   
4.
Smokers aged 18–65 yrs (N?=?1,044) who were able to quit for 24 hr were randomized using a 2?×?2 factorial design to compare nicotine gum to no gum use and self-help materials to no use of materials. All participants were offered a $100 incentive to quit and stay quit for 6 months. Six month abstinence was 27% in the gum groups, compared with 19% in the no-gum group (p?=?.002). Compared with the no-gum group, relapse occurred at a significantly lower rate in the gum group for the entire 12 months of follow-up There was no significant main effect for the self-help materials, no interaction between gum and materials, and no evidence that the effectiveness of gum differed between the sexes or between heavy and light smokers. Nicotine gum is an effective adjunct to minimal-contact smoking cessation materials plus monetary incentive in a population-based sample of smokers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
A total of 424 smokers were randomized in a 2?×?2 factorial experiment. A pharmacologic factor contained 2 levels: transdermal nicotine patch (TNP; 21 mg) and placebo. A self-help behavioral treatment factor contained 2 levels: video-enhanced self-help treatment manual and self-help treatment manual only. At 2 months, TNP produced a higher level of abstinence (36%) than placebo (20%), p?  相似文献   
6.
Objective: Although active diabetes self-management is required to achieve glycemic control, adherence is poor among ethnic minorities, especially Latinos. Research shows that individuals who report greater social-environmental support resources for disease management manage their diabetes more effectively than those with fewer support resources. Methods: Path analysis was conducted to investigate the value of a multiple-mediator model in explaining how support resources for disease management influence hemoglobin A1c (HbA1c) levels in a sample of 208 Latinos with Type 2 diabetes recruited from low-income serving community clinics in San Diego County. We hypothesized that the relationship between support resources for disease-management and HbA1c would be mediated by diabetes self-management and/or depression. Results: Participants who perceived greater support resources for disease-management reported better diabetes self-management (β = .40, p  相似文献   
7.
Smokers (N?=?224) were randomized to 1 of 3 groups: (a) transdermal system (TNS) + placebo; (b) TNS + paroxetine (20 mg); (c) TNS + paroxetine (40 mg). Assignment to treatment was double-blind. Nicotine patch (TNS) treatment was provided for 8 weeks; paroxetine or placebo was provided for 9 weeks. Abstinence rates at Weeks 4, 10, and 26 were as follows: (a) TNS + placebo: 45%, 36%, and 25%; (b) TNS + paroxetine (20 mg): 48%, 33%, and 21 %; (c) TNS + paroxetine (40 mg): 57%, 39%, and 27%. The differences were not statistically significant. The combined treatment was more effective in reducing both craving and depression symptoms associated with smoking cessation. A subgroup analysis comparing compliant participants was also conducted. Abstinence rates at Weeks 4, 10, and 26 were as follows: (a) TNS + placebo: 46%, 35%, and 24%; (b) TNS + paroxetine (20 mg): 64%, 43%, and 33%; (c) TNS + paroxetine (40 mg): 74%, 51%, and 38%. The differences between paroxetine groups and placebo at Week 4 were statistically significant. Although paroxetine may add value to the current standard of care in excess of potential risk, more conclusive evidence is needed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Chlorinated intrinsic amorphous silicon films [a-Si:H(Cl)] and solar cell i-layers were fabricated using electron cyclotron resonance-assisted chemical vapor deposition (ECR-CVD) and SiH2Cl2 source gas. n–i–p solar cells deposited on ZnO–coated SnO2 substrates had poor photovoltaic performances despite the good electronic properties measured on the a-Si:H(Cl) films. Improved open–circuit voltage (Voc) of 0.84 V and fill factor (FF) of 54% were observed in n–i–p solar cells by providing an n/i buffer layer and by using Ga-doped ZnO coated glass substrates. However, the FF improvement was still rather poor, which is thought to originate from high interface recombination in the ECR deposited solar cells. The Voc and the FF showed much stable feature against light soaking.  相似文献   
9.
We investigated serine/threonine protein phosphatase (PP) activity and the expression of PP2A during growth and differentiation of epidermal keratinocytes in culture. Keratinocyte PP activity was strongly inhibited by calyculin A and okadaic acid, indicating that the activity was mainly due to PP2A and PP1. The phosphatase activity decreased to about 20% of the initial (day 1) level by the time of confluence and to about 10% at day 7 postconfluence. In contrast to activity, the level of expression of the PP2A catalytic subunit protein and the mRNA for the two isoforms increased slightly over the period of growth. Keratinocyte differentiation was shown by a significant increase in profilaggrin expression after confluence. Keratinocytes were also cultured from individuals affected with harlequin ichthyosis. This severe hyperkeratotic skin disorder has abnormal lipid structures and is blocked in the PP2A-dependent conversion of phosphorylated profilggrin to the non-phosphorylated filaggrin. The PP activity in harlequin cultures was lower than in normal cultures (about 20% of the subconfluent normal control value) and decreased even further in confluent cultures. In contrast, the level of expression of the PP2A catalytic subunit protein and mRNA for the two isoforms was similar to that of normal keratinocytes and increased with confluence. These results suggest that PP activity in keratinocytes is regulated in a post-translational manner; they also support the possibility of impaired or reduced function of PPs in harlequin ichthyosis.  相似文献   
10.
We isolated rat UCP2 cDNA, which has been proposed to play an important role in mammalian thermogenesis and body weight regulation. The nucleotide sequence of the cDNA revealed that the rat UCP2 protein is composed of 309 amino acid residues, and is 99% and 95% identical to the mouse and human proteins, respectively. The molecular weight of rat UCP2, calculated from the predicted amino acid sequence, was 33,369, and the UCP2 protein of this size was detected when the cDNA was expressed in vitro. Northern blot analysis revealed that the corresponding mRNA is approximately 1.7 kb in size, and is expressed in a variety of rat organs, with predominant expression in the heart, lung and spleen. UCP2 mRNA levels in the heart, liver, muscle and epididymal adipose tissue of Zucker fatty (fa/fa) rats were comparable to those in the lean littermates, while ob mRNA level markedly increased in the epididymal adipose tissue of Zucker (fa/fa) rats.  相似文献   
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