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  1. Article ; Online: The 2022 Ferno Award Address: CrEATE, an Efficient Crossover Evaluation of Addiction Treatment Efficacy.

    Perkins, Kenneth A

    Nicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco

    2022  Volume 25, Issue 1, Page(s) 77–85

    Abstract: Dozens of drugs have been evaluated in recent decades for initial evidence of efficacy to aid smoking cessation (i.e. "early Phase 2" testing, according to U.S. FDA terminology), with the vast majority failing to show efficacy. Even small randomized ... ...

    Abstract Dozens of drugs have been evaluated in recent decades for initial evidence of efficacy to aid smoking cessation (i.e. "early Phase 2" testing, according to U.S. FDA terminology), with the vast majority failing to show efficacy. Even small randomized clinical trials (RCTs), the most common early Phase 2 tests, are costly undertakings, made more unappealing by their high likelihood of failure. At the same time, another early Phase 2 approach, acute tests of drug effects on surrogate endpoints such as withdrawal or craving severity, are more practical but have little predictive clinical validity. Described here is an innovative procedure that optimally combines the validity of clinical trials with the practical advantages of surrogate endpoint studies to more efficiently determine whether or not a novel drug warrants continued clinical development. This CrEATE procedure, or Crossover Evaluation of Addiction Treatment Efficacy, does so by assessing short-term quit success in smokers highly motivated to quit when briefly treated with active drug versus placebo in a crossover design, so that quit efficacy from both conditions is compared within participants. The program to develop and evaluate CrEATE demonstrates its sensitivity to efficacy from all three FDA-approved first-line cessation medications (NRT, varenicline, bupropion), tested here as model drugs, as well as specificity in identifying lack of efficacy with a drug known to be ineffective for cessation (modafinil). CrEATE has subsequently been used to evaluate a few novel interventions, concluding they lack efficacy in increasing quit success. Future directions for the potential utility of CrEATE are provided. Implications: The ability of CrEATE to reach a Go/No Go decision more quickly and with far less cost lowers the risk of failure, meaning widespread use of the procedure should encourage the evaluation of more novel candidate drugs. With its greater efficiency, failed tests, unfortunately the most likely outcome in early Phase 2 studies, will cause less waste of resources. At the same time, CrEATE tests that indicate a novel treatment has efficacy will justify the substantial time and expense of moving forward to evaluate the drug in late Phase 2 RCTs.
    MeSH term(s) Humans ; Nicotinic Agonists/therapeutic use ; Cross-Over Studies ; Benzazepines/therapeutic use ; Smoking/drug therapy ; Varenicline/therapeutic use ; Bupropion/therapeutic use ; Treatment Outcome
    Chemical Substances Nicotinic Agonists ; Benzazepines ; Varenicline (W6HS99O8ZO) ; Bupropion (01ZG3TPX31)
    Language English
    Publishing date 2022-06-04
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1452315-2
    ISSN 1469-994X ; 1462-2203
    ISSN (online) 1469-994X
    ISSN 1462-2203
    DOI 10.1093/ntr/ntac139
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Acute nicotine reinforcement requires ability to discriminate the stimulus effects of nicotine.

    Perkins, Kenneth A

    Experimental and clinical psychopharmacology

    2020  Volume 30, Issue 3, Page(s) 253–268

    Abstract: ... policy for reducing risk of tobacco dependence is adapted from Kenneth A. Perkins's ...

    Abstract This review of research on behavioral discrimination of nicotine and how it informs public health policy for reducing risk of tobacco dependence is adapted from Kenneth A. Perkins's American Psychological Association Division 28 (Psychopharmacology and Substance Abuse) 2020 Med Associates Brady/Schuster Award Lecture. The author's initial programmatic clinical research on nicotine is introduced, especially efforts to develop and validate a novel method of acute nicotine dosing. After the public health rationale for characterizing the discriminative stimulus effects of nicotine in humans are described, details from two separate programs of research on nicotine discrimination in humans are presented. The first, conducted with nicotine dosing by nasal spray, documented that humans could discriminate nicotine administered rapidly, examined nicotine's neuropharmacological specificity, identified discrimination threshold dose in smokers and nonsmokers, and explored other conditions that might alter ability to discriminate its effects. The second, more recent program focused on threshold doses for discrimination of nicotine by cigarette smoking, a program that was very difficult to do until the past decade, and how nicotine's self-reported "reward" and preference via choice behavior relate to its discriminability. Differences due to menthol and degree of tobacco dependence were also examined. For each of these two programs, the main findings of selected studies are noted, followed by very recent work on nicotine discrimination and choice that informs Food and Drug Administration's efforts to formulate public policy to improve health and reduce the nearly half million American deaths per year due to persistent tobacco use. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
    MeSH term(s) Discrimination Learning ; Dose-Response Relationship, Drug ; Humans ; Nicotine/pharmacology ; Reinforcement, Psychology ; Tobacco Use Disorder/psychology
    Chemical Substances Nicotine (6M3C89ZY6R)
    Language English
    Publishing date 2020-10-29
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 1209960-0
    ISSN 1936-2293 ; 1064-1297
    ISSN (online) 1936-2293
    ISSN 1064-1297
    DOI 10.1037/pha0000433
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Research on Behavioral Discrimination of Nicotine May Inform FDA Policy on Setting a Maximum Nicotine Content in Cigarettes.

    Perkins, Kenneth A

    Nicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco

    2020  Volume 21, Issue Suppl 1, Page(s) S5–S12

    Abstract: Introduction: The Food and Drug Administration may set a maximum nicotine content in cigarettes to minimize smoking's addictiveness. Our recent research may indirectly support setting levels applicable to the population of dependent smokers below 1 mg/g ...

    Abstract Introduction: The Food and Drug Administration may set a maximum nicotine content in cigarettes to minimize smoking's addictiveness. Our recent research may indirectly support setting levels applicable to the population of dependent smokers below 1 mg/g (mg nicotine/g of tobacco filler).
    Methods: Using a within-subjects design in laboratory-based studies totaling 61 nontreatment seeking adult dependent smokers, Spectrum research cigarettes with nicotine contents ranging from 1.3 to 17 mg/g (just one per session) were compared with the lowest content available, 0.4 mg/g. Identified for each participant was the smallest difference in nicotine content, or "threshold," between cigarettes that still supported behavioral discrimination (ie, ability to objectively distinguish their difference). The next lower nicotine content cigarette, not discriminated (by definition), was labeled their "subthreshold." Subjective perceptions and choice behavior were also assessed.
    Results: Thresholds varied widely among all 61 smokers but, importantly, fewer than 7% of smokers could discriminate the two lowest, 1.3 versus 0.4 mg/g nicotine, meaning more than 90% could not do so. Moreover, we found a consistent association between their nicotine discrimination threshold and their subjective perceptions and subsequent reinforcement behavior later in the session. Specifically, a participant's discrimination threshold cigarette was also more highly rated and preferred (ie, self-administered), whereas their subthreshold cigarette was rated similarly to the 0.4 mg/g and not preferred.
    Conclusions: Cigarette nicotine content below the threshold for perceiving nicotine's effects (ie, its discriminability) in nearly all smokers from a no nicotine comparison is likely below 1.0 mg/g, or less than or equal to 10% of that in typical commercial cigarettes.
    Implications: Cigarettes with nicotine contents able to be discriminated (threshold) are also reinforcing, and those unable to be discriminated are not reinforcing, as anticipated. Yet, research explicitly comparing cigarettes with contents below 1.0 mg/g versus no nicotine (ie, a "placebo") is needed with larger samples. Results may confirm what nicotine content lower than 1.0 mg/g is below the threshold for discrimination (and self-administration) in the vast majority (>95%) of adult dependent smokers as well as teens beginning to smoke. Identifying that content would strongly support the Food and Drug Administration policy to establish a maximum nicotine content in cigarettes that will not maintain dependence.
    MeSH term(s) Adult ; Humans ; Nicotine/analysis ; Nicotine/standards ; Smokers/psychology ; Smokers/statistics & numerical data ; Smoking/epidemiology ; Smoking/psychology ; Tobacco Products/legislation & jurisprudence ; Tobacco Products/standards ; United States ; United States Food and Drug Administration
    Chemical Substances Nicotine (6M3C89ZY6R)
    Language English
    Publishing date 2020-01-31
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1452315-2
    ISSN 1469-994X ; 1462-2203
    ISSN (online) 1469-994X
    ISSN 1462-2203
    DOI 10.1093/ntr/ntz136
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Book ; Audio / Video ; Thesis: Turbulence structure in gas flows relaminarizing by heating /Kenneth Roy Perkins

    Perkins, Kenneth Roy

    1975  

    Language English
    Size 1 Mikrofilm
    Publisher University Microfilms Int
    Publishing place Ann Arbor
    Document type Book ; Audio / Video ; Thesis
    Thesis / German Habilitation thesis Univ. of Arizona, Ph. D. Thesis--Tucson, 1975
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  5. Article ; Online: Acute subjective sensory perceptions predict relative reinforcing effects of smoked nicotine.

    Karelitz, Joshua L / Perkins, Kenneth A

    Addictive behaviors

    2021  Volume 117, Page(s) 106835

    Abstract: Introduction: Smoking is believed partially reinforcing via immediate sensory perceptions. Yet, unknown is whether a cigarette's relative reinforcing efficacy can be predicted by these perceptions and whether this relationship may vary due to ... ...

    Abstract Introduction: Smoking is believed partially reinforcing via immediate sensory perceptions. Yet, unknown is whether a cigarette's relative reinforcing efficacy can be predicted by these perceptions and whether this relationship may vary due to constituents known to alter those perceptions.
    Methods: Sensory perceptions of acute smoking were examined as predictors of subsequent cigarette choice behavior. Also tested was whether nicotine content or menthol affected this relationship. Adult dependent smokers (N = 37) participated in five sessions comparing cigarettes varying in nicotine contents (NIC; 1.3, 2.3, 5.5, 11.2, and 17.4 mg/g), relative to the very lowest nicotine content, 0.4 mg/g (VLNC). Non-menthol (n = 17) and menthol (n = 20) cigarettes-matched on nicotine-were provided based on participant preference. One NIC was compared versus VLNC per session (single-blinded); NIC content order was randomized across sessions on separate days. Perceptions (e.g., "liking", "satisfying") were measured immediately after initial sampling of NIC or VLNC, followed by a validated puff-by-puff choice procedure to determine preference for each NIC versus VLNC.
    Results: NIC perceptions (difference from VLNC) and puff choices increased with nicotine. Menthol moderated associations between perceptions and nicotine; and between puff choices and nicotine. Perceptions were predictive of puff choice-greater magnitude of difference in perceptions between VLNC and NIC led to more NIC puff choices. When testing perceptions' prediction of puff choices, neither the main effect of menthol or interaction of Perceptions X Nicotine Condition were significant.
    Conclusions: Consistent with assumed-but rarely tested-causes of smoking reinforcement, sensory perceptions from a cigarette predict its relative reinforcing efficacy.
    MeSH term(s) Adult ; Humans ; Nicotine ; Perception ; Smoke ; Smoking Cessation ; Tobacco Products
    Chemical Substances Smoke ; Nicotine (6M3C89ZY6R)
    Language English
    Publishing date 2021-01-15
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 197618-7
    ISSN 1873-6327 ; 0306-4603
    ISSN (online) 1873-6327
    ISSN 0306-4603
    DOI 10.1016/j.addbeh.2021.106835
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: FDA Policy on Setting Maximum Nicotine Content in Cigarettes.

    Perkins, Kenneth A

    Nicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco

    2017  Volume 21, Issue 7, Page(s) 996–997

    Language English
    Publishing date 2017-12-02
    Publishing country England
    Document type Journal Article
    ZDB-ID 1452315-2
    ISSN 1469-994X ; 1462-2203
    ISSN (online) 1469-994X
    ISSN 1462-2203
    DOI 10.1093/ntr/nty068
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Preclinical and clinical research on the discriminative stimulus effects of nicotine.

    Shoaib, Mohammed / Perkins, Kenneth A

    Neuropharmacology

    2020  Volume 170, Page(s) 108063

    Abstract: Across species, nicotine can produce robust discriminative stimulus (DS) effects, as with other drugs of abuse, a feature that has been harnessed to advance our understanding on the neuropharmacological mechanisms of nicotine's actions. With the crucial ... ...

    Abstract Across species, nicotine can produce robust discriminative stimulus (DS) effects, as with other drugs of abuse, a feature that has been harnessed to advance our understanding on the neuropharmacological mechanisms of nicotine's actions. With the crucial role played by nicotine in supporting tobacco dependence, nicotine DS effects have presented an ideal platform to develop novel generation of smoking cessation compounds. Findings from preclinical strands of research have invigorated the field of human discrimination research to objectively assess nicotine's interoceptive stimulus effects. As such, translation studies provide proof of concept for nicotine DS research as a method to assess the subjective effects of nicotine per se, separate from non-nicotine stimuli involved in smoking. Recent clinical studies with low doses have demonstrated that perceiving nicotine's DS effects is necessary, yet not sufficient, for that dose to be reinforcing. These measures have been instrumental in developing novel strategies with regards to establishing threshold doses of nicotine contained in tobacco products, to then determine subthreshold doses that cannot be discriminated and, therefore, fail to maintain reinforcement. Findings from preclinical and clinical nicotine DS research could substantially inform public health policies aimed at regulating nicotine content of consumer products so that they minimize risks of dependency. This article is part of the special issue on 'Contemporary Advances in Nicotine Neuropharmacology'.
    MeSH term(s) Animals ; Clinical Trials as Topic/methods ; Discrimination Learning/drug effects ; Discrimination Learning/physiology ; Drug Evaluation, Preclinical/methods ; Humans ; Nicotine/metabolism ; Nicotine/pharmacology ; Nicotinic Agonists/metabolism ; Nicotinic Agonists/pharmacology ; Reinforcement, Psychology ; Smoking/metabolism ; Smoking/psychology ; Smoking Cessation Agents/pharmacology ; Smoking Cessation Agents/therapeutic use ; Species Specificity ; Tobacco Use Disorder/drug therapy ; Tobacco Use Disorder/metabolism ; Tobacco Use Disorder/psychology
    Chemical Substances Nicotinic Agonists ; Smoking Cessation Agents ; Nicotine (6M3C89ZY6R)
    Language English
    Publishing date 2020-03-24
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Review
    ZDB-ID 218272-5
    ISSN 1873-7064 ; 0028-3908
    ISSN (online) 1873-7064
    ISSN 0028-3908
    DOI 10.1016/j.neuropharm.2020.108063
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Differences in acute reinforcement across reduced nicotine content cigarettes.

    Perkins, Kenneth A / Karelitz, Joshua L

    Psychopharmacology

    2020  Volume 237, Issue 6, Page(s) 1885–1891

    Abstract: Rationale: The smallest difference in nicotine that can change a smoker's cigarette preference is not clearly known.: Objective: A procedure to efficiently identify the difference in nicotine needed to change cigarette preference could help inform ... ...

    Abstract Rationale: The smallest difference in nicotine that can change a smoker's cigarette preference is not clearly known.
    Objective: A procedure to efficiently identify the difference in nicotine needed to change cigarette preference could help inform research to gauge effects of a nicotine reduction policy.
    Methods: Using a within-subject design, we assessed preference for research cigarettes varying in nicotine contents (NIC; 18.7, 10.8, 5.3, 2.3, and 1.3 mg/g of tobacco), relative to a very low nicotine cigarette (VLNC; 0.4 mg/g), in 17 adult-dependent non-menthol smokers abstinent overnight. Only one NIC was compared vs. the VLNC per session, with order of the five NIC contents randomized across sessions on five separate days. Preference for each NIC vs. VLNC was determined by validated forced choice procedure, with those NIC chosen more than VLNC indicating greater reinforcement due to greater nicotine per se. Secondarily, less preference for lower NIC (vs. VLNC), relative to choice for the highest NIC, 18.7 mg/g (vs. VLNC), indexed reduced reinforcement.
    Results: Overall, NIC choices increased as their nicotine increased, as anticipated. Relative to the 0.4 mg/g VLNC, choice was greater for NIC ≥ 5.3 mg/g but not ≤ 2.3 mg/g. Correspondingly, relative to choice for 18.7 mg/g, choice was less for NIC ≤ 2.3 mg/g but not ≥ 5.3 mg/g.
    Conclusions: Although replication with larger samples and longer access is needed, results indicate that nicotine reduction to ≤ 2.3 mg/g in cigarettes would attenuate reinforcement. This choice procedure may efficiently inform future clinical trials to assess relative reinforcing effects of smoking reduced nicotine cigarettes.
    MeSH term(s) Adult ; Choice Behavior/drug effects ; Choice Behavior/physiology ; Cigarette Smoking/psychology ; Cigarette Smoking/therapy ; Dose-Response Relationship, Drug ; Female ; Humans ; Male ; Nicotine/administration & dosage ; Reinforcement, Psychology ; Smokers/psychology ; Smoking Cessation/methods ; Smoking Cessation/psychology ; Tobacco Products ; Tobacco Use Cessation Devices
    Chemical Substances Nicotine (6M3C89ZY6R)
    Language English
    Publishing date 2020-03-27
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 130601-7
    ISSN 1432-2072 ; 0033-3158
    ISSN (online) 1432-2072
    ISSN 0033-3158
    DOI 10.1007/s00213-020-05509-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Increased migration and motility in XIAP-null cells mediated by the C-RAF protein kinase.

    Russell, Lauren G / Davis, Lydia A K / Hunter, Jill E / Perkins, Neil D / Kenneth, Niall S

    Scientific reports

    2022  Volume 12, Issue 1, Page(s) 7943

    Abstract: The product encoded by the X-linked inhibitor of apoptosis (XIAP) gene is a multi-functional protein which not only controls caspase-dependent cell death, but also participates in inflammatory signalling, copper homeostasis, response to hypoxia and ... ...

    Abstract The product encoded by the X-linked inhibitor of apoptosis (XIAP) gene is a multi-functional protein which not only controls caspase-dependent cell death, but also participates in inflammatory signalling, copper homeostasis, response to hypoxia and control of cell migration. Deregulation of XIAP, either by elevated expression or inherited genetic deletion, is associated with several human disease states. Reconciling XIAP-dependent signalling pathways with its role in disease progression is essential to understand how XIAP promotes the progression of human pathologies. In this study we have created a panel of genetically modified XIAP-null cell lines using TALENs and CRISPR/Cas9 to investigate the functional outcome of XIAP deletion. Surprisingly, in our genetically modified cells XIAP deletion had no effect on programmed cell death, but instead the primary phenotype we observed was a profound increase in cell migration rates. Furthermore, we found that XIAP-dependent suppression of cell migration was dependent on XIAPdependent control of C-RAF levels, a protein kinase which controls cell signalling pathways that regulate the cytoskeleton. These results suggest that XIAP is not necessary for control of the apoptotic signalling cascade, however it does have a critical role in controlling cell migration and motility that cannot be compensated for in XIAP-knockout cells.
    MeSH term(s) Apoptosis ; Caspases/metabolism ; Lymphocytes, Null/metabolism ; Proto-Oncogene Proteins c-raf/metabolism ; Signal Transduction ; X-Linked Inhibitor of Apoptosis Protein/metabolism
    Chemical Substances X-Linked Inhibitor of Apoptosis Protein ; Proto-Oncogene Proteins c-raf (EC 2.7.11.1) ; Caspases (EC 3.4.22.-)
    Language English
    Publishing date 2022-05-13
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-022-11438-8
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: A Forced-Choice Procedure to Assess the Acute Relative Reinforcing Effects of Nicotine Dose per se in Humans.

    Perkins, Kenneth A / Karelitz, Joshua L

    Nicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco

    2019  Volume 22, Issue 10, Page(s) 1685–1693

    Abstract: Introduction: A method to assess acute reinforcement due to nicotine may aid identification of doses needed to maintain dependence. After describing development of a forced-choice procedure, results are presented from two studies using it to determine ... ...

    Abstract Introduction: A method to assess acute reinforcement due to nicotine may aid identification of doses needed to maintain dependence. After describing development of a forced-choice procedure, results are presented from two studies using it to determine the relative reinforcing effects of nicotine dose per se.
    Aims and methods: Choice between a higher versus a very low or no nicotine option, via smoking (Study 1, n = 59) and via nasal spray (Study 2, n = 42), was assessed in nontreatment-seeking dependent smokers abstinent overnight. Using a within-subject design, different nicotine levels for each product were administered under blind conditions, initially to assess their discriminability (Study 1: 1.3-17 mg/g each vs. 0.4 mg/g nicotine Spectrum cigarettes; Study 2: 2.5 µg/kg vs. 0 µg/kg nicotine per spray). At the end of sessions for each study, participants engaged in forced-choice trials to assess preference, requiring a fixed number of puffs/sprays for one and/or the other.
    Results: Confirming the procedure's validity, the choice of the higher nicotine option was significantly greater than that for the very low or no nicotine option in both studies. In Study 1, choice relative to 0.4 mg/g was greater for cigarettes 5.3 mg/g or more but not 2.3 mg/g or less (p = .003 for the interaction of higher content vs. 0.4 mg/g comparison). In Study 2, choice was greater for the nicotine versus placebo spray (p < .005), as nicotine was preferred nearly twice as much as the placebo.
    Conclusion: This forced-choice procedure may efficiently determine the relative reinforcing value of a nicotine dose per se.
    Implications: The forced-choice procedure described here may identify nicotine doses that are acutely reinforcing in dependent smokers. A priori research of choice comparisons between small versus zero nicotine doses could inform clinical research in larger and more diverse samples to determine nicotine contents in cigarettes, and perhaps in other commercial products, that are not reinforcing and, thus, likely to reduce the risk of their addictiveness. This procedure may also be applicable to assessing changes in acute nicotine reinforcement due to different product formulations, novel drugs, or other manipulations, perhaps helping inform development of new interventions for cessation or harm reduction.
    MeSH term(s) Adult ; Behavior, Addictive ; Choice Behavior ; Female ; Humans ; Male ; Nicotine/administration & dosage ; Reinforcement, Psychology ; Smokers/psychology ; Smoking/epidemiology ; Smoking Cessation/methods ; Young Adult
    Chemical Substances Nicotine (6M3C89ZY6R)
    Language English
    Publishing date 2019-11-11
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1452315-2
    ISSN 1469-994X ; 1462-2203
    ISSN (online) 1469-994X
    ISSN 1462-2203
    DOI 10.1093/ntr/ntz224
    Database MEDical Literature Analysis and Retrieval System OnLINE

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