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21.
STEPHEN J. HEISHMAN DAVID J. K. BALFOUR NEAL L. BENOWITZ DOROTHY K. HATSUKAMI JON M. LINDSTROM JUDITH K. OCKENE 《Addiction (Abingdon, England)》1997,92(5):615-634
The proceedings of the second annual scientific conference of the Society for Research on Nicotine and Tobacco are summarized. The goal of the annual conference was to disseminate information about ongoing nicotine research from biological, behavioral and social perspectives. Data were presented describing our current understanding of the structure and function of neuronal nicotinic acetylcholine receptors, by which nicotine exerts most, if not all, of its effects in the brain. The conformational complexity of receptor subunits expressed in different brain areas contributes significantly to the complexity of responses observed to nicotinic agonists. Nicotine is being developed as a medication that might be used to maintain smoking cessation and to treat various medical diseases. The potential toxicity of nicotine, apart from cigarette smoking, is an important variable in assessing the benefits and risks of such therapeutic applications. The risks of nicotine-containing medications appear to be far less than those associated with tobacco use. Recent data indicate that cigarette smoking is increasing among youth in the United States. Adolescent smokers are interested in quitting and make frequent quit attempts, but are usually not successful. Effective methods are needed to manage adolescent smokers before they become heavily addicted. Nicotine replacement as a pharmacological treatment for smoking cessation has made a significant contribution in improving quit rates. New medications have been developed that target specific populations of smokers. 相似文献
22.
A New Approach to Percutaneous Subclavian Venipuncture to Avoid Lead Fracture or Central Venous Catheter Occlusion 总被引:5,自引:0,他引:5
JEAN E. MAGNEY DAVID H. STAPLIN DAVID M. FLYNN DAVID W. HUNTER 《Pacing and clinical electrophysiology : PACE》1993,16(11):2133-2142
Pacemaker and defibrillator leads and central venous catheters placed by commonly recommended techniques have been found to pass through the subclavius muscle, the costocaracoid ligament, or the costoclavicular ligament before entering veins medial to the first rib. Entrapment by these soft tissues subjects leads and catheters to stresses imposed by movements of the ipsilateral upper extremity. Accordingly, a new approach has been developed that introduces the lead or catheter into the subciavian vein near the lateral border of the first rib. This placement avoids soft tissue entrapment and may extend the longevity of leads and catheters. 相似文献
23.
Patient Characteristics Associated with the Labelling of Asthma 总被引:1,自引:0,他引:1
Patient characteristics associated with the asthma label wereinvestigated in 262 children, aged 8 years, who reported wheezingillness in the previous 12 months. Children were first identifiedby a screening questionnaire administered to the parents ofall 8 year old schoolchildren in Croydon, south London. Interviewswere conducted with those reported to have had a wheezing illnessin the previous 12 months to obtain details of the child's illness,medical care, demographic and socioeconomic characteristics.Multivariate analysis showed that the likelihood of being labelledasthmatic was increased in those who had a parental historyof hayfever [odds ratio (OR) = 2.24, 95% confidence interval(Cl) = 1.224.14] or at least two allergic provoking factors(OR = 3.83, 95% Cl = 1.4410.15). No significant associationswere found between asthma labelling and children's socioeconomiccharacteristics or use of general practitioner services. Thesefindings suggest that wheeze is likely to be labelled asthmawhen the clinical history suggests an allergic aetiology. 相似文献
24.
Oral health maintenance for the musical performer is an essential component of the training and experience. Normal tooth and dental arch development permit vocalists. and players of wind instruments and chin-held wind instruments to achieve their optimum acoustic and esthetic musical performance. Dental disease or disorders that high-quality performance years of vocalists and instrumentalists. 相似文献
25.
GEORGE STAVROPOULOS KOSTAS KARAGIANNIS PAUL CORDOPATIS DAVID HALLE CHAIM GILON GIORA BAR-AKIVA ZVI SELINGER MICHAEL CHOREV 《Chemical biology & drug design》1991,37(3):180-184
The analogues [Glu(OBzl)11]SP6–11 and [Glu(OBzl)11]SP5–11 of the C-terminal hexapeptide and heptapeptide of Substance P have been synthesized by conventional solution methods. In each analogue the SCH3 group of Met11 is replaced by the COOCH2C6H5 group. The in vitro activity of both analogues has been determined on three biological preparations: guinea pig ileum (GPI), rat vas deferens (RVD), and rat portal vein (RPV). The selectivity for the different receptors has been studied by utilizing atropine-treated guinea pig ileum (GPI + At). The results showed that both analogues are mainly active on GPI through the NK-1 receptor and that both analogues are equipotent to Substance P. 相似文献
26.
FREDERIC W-B. DELEYIANNIS MD MPhil MPH DAVID B. THOMAS MD DrPH From the Departments of Otolaryngology–Head Neck Surgery Epidemiology University of Washington Seattle; the Division of Public Health Science Fred Hutchinson Cancer Research Center. 《Otolaryngology--head and neck surgery》1997,116(6):630-636
A cohort of 5180 patients with head and neck cancer, who were part of the tumor registry of the Surveillance, Epidemiology, and End Results area of western Washington State, was followed up for as many as 15 years to determine the risk of lung cancer. A sample of 522 patients from this cohort was interviewed to determine smoking history. Lung cancer developed in 356 (6.9%) of the 5180 patients. The overall annual incidence of lung cancer remained relatively constant between approximately 1.0% and 2.0% during the 15 years of follow-up. Men had an increased risk of lung cancer compared with women (relative risk [RR] = 1.56; 95% confidence interval [CI] = 1.18 to 2.03). Compared with patients with oral cavity cancer (RR = 1.00), the relative risk of lung cancer developing by the site of the index tumor was 0.63 (95% CI = 0.40 to 0.98) for lip, 1.12 (95% CI = 0.81 to 1.56) for intrinsic larynx, 1.73 (95% CI = 1.21 to 2.47) for oropharynx, 1.84 (95% CI = 1.16 to 2.92) for hypopharynx, and 2.28 (95% CI = 1.60 to 3.24) for extrinsic larynx. Among the 522 patients who were interviewed, men smoked more than women ( p < 0.0001), and patients with laryngeal or pharyngeal cancer smoked more than patients with cancer of the lip or the oral cavity ( p < 0.05). Among patients with head and neck cancer, the risk of lung cancer is highest for men and for patients with cancer of the pharynx or extrinsic larynx. These findings may be explained by differences in smoking consumption. (Otolaryngol Head Neck Surg 1997;116:630-6.) 相似文献
27.
We present our approach to the preoperative preparation and anaesthetic management for awake craniotomy in a 12-year-old boy. Management included conscious sedation with a propofol infusion plus local anaesthetic infiltration of the scalp, periosteum, and dura. The complications which may be encountered during such procedures and their treatments are reviewed. 相似文献
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