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Mario Perez-Reyes MD Robert E. Hicks PhD Jean Bumberry BS A. Robert Jeffcoat PhD C. Edgar Cook PhD 《Alcoholism, clinical and experimental research》1988,12(2):268-276
This is a report of the results of a placebo-controlled study in which the effects of the interaction between ethanol and marihuana on drug plasma concentrations, subjective ratings of intoxication, heart rate acceleration, and psychomotor performance were investigated. Six healthy, male, paid volunteers, moderate users of ethanol and marihuana, participated in the study. Ethanol (0.42 g/kg, 0.85 g/kg, or placebo) was administered over a 30-min interval. Fifteen minutes later the subjects smoked, in their customary manner, NIDA cigarettes containing 2.4% or 0.0004% (placebo) delta-9-tetrahydrocannabinol (THC). Each subject was tested in a single-blind, latin-square crossover design with the following six conditions: placebo ethanol/placebo marihuana; low dose ethanol/placebo marihuana; high dose ethanol/placebo marihuana; placebo ethanol/marihuana; low dose ethanol/marihuana; and high dose ethanol/marihuana. The variables measured in the study were: (a) subjective rating of ethanol and/or marihuana intoxication; (b) heart rate; (c) accuracy and latency of response in the Simulator Evaluation of Drug Impairment (SEDI) task; (d) blood ethanol concentration by gas chromatography; and (e) plasma concentration of THC by radioimmunoassay. The results indicate that the decrements due to ethanol in performance of skills necessary to drive an automobile were significantly enhanced by marihuana in an additive and perhaps synergistic manner. The administration of ethanol prior to marihuana smoking did not produce significant effects on the subjective rating of "high," heart rate acceleration, or THC plasma concentration. 相似文献
54.
The patellofemoral joint was imaged with magnetic resonance (MR) in the axial plane while the knee was positioned from 0 degrees to 32 degrees of flexion (nine positions). These multiple sequential images obtained within the early phases of flexion of the knee were viewed in a "cine-loop" format, producing a kinematic study that clearly demonstrated the relationship of the patella to the trochlear groove. Four healthy subjects and one patient with known bilateral subluxing patellae were studied. The preliminary results suggest that kinematic MR imaging of the patellofemoral joint is potentially useful for the evaluation of patellar tracking abnormalities. 相似文献
55.
Anaphylactic hypersensitivity in isolated smooth muscle preparations from adjuvant-treated guinea-pigs
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![点击此处可从《Immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Anaphylactic hypersensitivity of isolated guinea-pig ileum preparations has been evaluated by investigation of antigen-dose/response relationships, in vitro. The influence of Freund's adjuvants on active sensitization has been investigated. In contrast to the inhibitory influence previously observed in vivo, the degree of hypersensitivity of isolated tissues in vitro was potentiated by the adjuvants. It is thought that high circulating titres of antibody in vivo exerted a protective or neutralizing effect in relation to challenging doses of antigen. Isolated tissues were freed from this influence. Tissues sensitized with the aid of Freund's complete adjuvant (FCA) revealed the influence of other inhibitory mechanisms, due probably to interaction of various antibody types. 相似文献
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BACKGROUND: Little research has examined genetic and environmental contributions to psychopathic personality traits. Additionally, no studies have examined etiological connections between psychopathic traits and the broad psychopathological domains of internalizing (mood and anxiety) and externalizing (antisocial behavior, substance abuse). The current study was designed to fill these gaps in the literature. METHOD: Participants were 626 pairs of 17-year-old male and female twins from the community. Psychopathic traits were indexed using scores on the Multidimensional Personality Questionnaire (MPQ). Symptoms of internalizing and externalizing psychopathology were obtained via structured clinical interviews. Structural equation modeling was used to estimate genetic and environmental influences on psychopathic personality traits as well as the degree of genetic overlap between these traits and composites of internalizing and externalizing. RESULTS: Twin analyses revealed significant genetic influence on distinct psychopathic traits (Fearless Dominance and Impulsive Antisociality). Moreover, Fearless Dominance was associated with reduced genetic risk for internalizing psychopathology, and Impulsive Antisociality was associated with increased genetic risk for externalizing psychopathology. CONCLUSIONS: These results indicate that different psychopathic traits as measured by the MPQ show distinct genetically based relations with broad dimensions of DSM psychopathology. 相似文献
57.
Tortoriello DV; McGovern PG; Colon JM; Loughlin J; Santoro N 《Human reproduction (Oxford, England)》1998,13(11):3005-3008
We report an instance of critical ovarian hyperstimulation syndrome in a
highly responsive in-vitro fertilization patient despite the preventive
measure of a 4 day 'coast' interval during which no gonadotrophins were
administered while gonadotrophin-releasing hormone agonist therapy
continued until serum oestradiol concentrations fell below 3000 pg/ml.
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58.
Incidence and determinants of moderate COPD (GOLD II) in male smokers aged 40–65 years: 5-year follow up
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Roeland MM Geijer Alfred PE Sachs Theo JM Verheij Philippe L Salom Jan-Willem J Lammers Arno W Hoes 《The British journal of general practice》2006,56(530):656-661
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major health problem with an estimated prevalence of 10-15% among smokers. The incidence of moderate COPD, as defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD), is largely unknown. AIM: To determine the cumulative incidence of moderate COPD (forced expiratory volume in 1 second/forced vital capacity ratio [FEV1/FVC] <0.7 and FEV1 <80% predicted) and its association with patient characteristics in a cohort of male smokers. DESIGN: Prospective cohort study. SETTING: The city of IJsselstein, a small town in the Netherlands. METHOD: Smokers aged 40-65 years who were registered with local GPs, participated in a study to identify undetected COPD. Baseline measurements were taken in 1998 of 399 smokers with normal spirometry (n = 292) or mild COPD (FEV1/FVC <0.7 and FEV1 >or=80% predicted, n = 107) and follow-up measurements were conducted in 2003. RESULTS: After a mean follow-up of 5.2 years, 33 participants developed moderate COPD (GOLD II). This showed an estimated cumulative incidence of 8.3% (95% CI = 5.8 to 11.4) and a mean annual incidence of 1.6%. No participant developed severe airflow obstruction. The risk of developing moderate COPD in smokers with baseline mild COPD (GOLD I) was five times higher than in those with baseline normal spirometry (one in five versus one in 25). CONCLUSIONS: In a cohort of middle-aged male smokers, the estimated cumulative incidence of moderate COPD (GOLD II) over 5 years was relatively high (8.3%). Age, childhood smoking, cough, and one or more GP contacts for lower respiratory tract problems were independently associated with incident moderate COPD. 相似文献
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