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91.
Herbert J. Weingartner Robert Rawlings David T. George Michael Eckardt 《Psychopharmacology》1998,138(3-4):311-317
This study was designed to examine and contrast cognitive effects (explicit memory and access to semantic knowledge) of the
benzodiazepine Halcion (triazolam) in ten normal volunteers and ten cognitively unimpaired detoxified alcoholics. The two
groups were indistinguishable from one another under placebo conditions on all measures of cognitive functioning. Under Halcion
test conditions (0.375 mg PO), both groups were about equally impaired in their recall of to-be-remembered information. However,
alcoholics, were more likely to recall information that they were not asked to remember (intrusion errors) on all measures
of explicit remembering. Alcoholics also generated relatively uncommon (low frequency) responses from semantic memory, rather
than common, categorically related associations in response to stimuli such as types of vegetables, flowers, and fruit following
the administration of Halcion, but were not different from normal volunteers in the types of responses generated under placebo
conditions. These findings suggest that a drug challenge that simulates many of the effects of acute alcohol administration
induces alcoholics to think and remember differently (qualitatively) from normal volunteers.
Received: 7 July 1997 / Final version: 22 September 1997 相似文献
92.
Reinstatement of alcohol-seeking by priming injections of alcohol and exposure to stress in rats 总被引:10,自引:5,他引:5
A. D. Lê B. Quan W. Juzytch P. J. Fletcher N. Joharchi Y. Shaham 《Psychopharmacology》1998,135(2):169-174
Previous studies using a reinstatement procedure have found that acute reexposure to the self-administered drug and exposure
to footshock stress reinstate heroin and cocaine seeking after prolonged drug-free periods. Here we tested whether these findings
generalize to alcohol-taking behavior. Male rats were initially allowed to consume alcohol in a two-bottle choice procedure
(water versus alcohol) for 30 min/day for 36 days. Rats were then trained for 60 min/day in operant chambers to press a lever
for the drug (0.13 ml of 12% w/v of an alcohol solution) for up to 55 days. After stable drug-taking on a fixed-ratio-3 schedule
of reinforcement was obtained, lever pressing for alcohol was extinguished by terminating drug delivery for 4–9 days. Reinstatement
of drug seeking was then determined after non-contingent priming injections of alcohol (0.24 and 0.48 g/kg; given IP and orally)
or exposure to intermittent footshock stress (5 and 15 min; 0.8 mA). Priming injections of alcohol produced a modest dose-dependent
reinstatement of drug seeking, whereas footshock stress potently reinstated extinguished alcohol seeking. In contrast, similar
parameters of footshock failed to reinstate extinguished sucrose-taking behavior in rats previously trained to lever press
for sucrose pellets. These findings extend previous reports on reinstatement of cocaine and heroin seeking by a footshock
stressor and by priming drug injections. It also appears that the reinstatement procedure provides an appropriate methodology
to study relapse to alcohol-taking behavior in the drug-free state.
Received: 9 April 1997 / Final version: 1 August 1997 相似文献
93.
Aaro Leinonen Topi Siniluoto Markku Päivänsalo Ari Karttunen Matti I. Kairaluoma Ilkka Suramo 《European radiology》1993,3(3):213-218
Nineteen patients with 49 symptomatic non-neoplastic non-parasitic simple hepatic cysts were subjected to ultrasonographically guided percutaneous aspiration and temporary injection of 99% ethanol into the cyst. Small cysts were treated twice, the large ones three times at the same sitting. The volume of alcohol per injection varied from 20 to 100 ml, depending on the size of the cyst. A cure was usually achieved with one ethanol sclerotherapy treatment. Only minor side effects such as transient pain and temperature elevation occurred. Forty-seven of the 49 cysts could be treated adequately, and did not recur during a follow-up period af 12–40 months. The results indicate that aspiration an and ethanol sclerotherapy is the treatment of choice in patients with symptomatic non-neoplastic simple hepatic cysts or polycystic liver disease.
Correspondence to: A. Leinonen 相似文献
94.
The role of the ethanol training dose on the ability of the selective 5-HT1 agonist TFMPP (m-trifluoromethylphenylpiperazine) to produce ethanol-like discriminative stimulus effects was evaluated in three groups of rats trained to discriminate 1.0 g/kg (n=5), 1.5 g/kg (n=6) or 2.0 g/kg (n=7) ethanol (IG) from water using a two-lever procedure with food reinforcement available under a fixed ratio 20 (FR 20) schedule. Ethanol generalization gradients were comparable in the three groups, indicating few potency differences in the ethanol stimulus across training dose. However, the ability of TFMPP (0.1–1.7 mg/kg; IP) to substitute for ethanol was dependent on the training dose. TFMPP resulted in partial substitution in the 1.0 g/kg group, complete substitution for 1.5 g/kg group and no substitution in the 2.0 g/kg ethanol training group. The results indicate a serotonergic component to the discriminative stimulus effects of an intermediate dose of ethanol that is not prominent as the dose of ethanol is raised. These data add further support for the hypothesis that ethanol produces a mixed discriminative cue, the components of which are not uniformly amplified when the dose of ethanol is increased. 相似文献
95.
为了更加准确地了解医学生智慧教室的使用需求,为智慧教室管理者在制定智慧教室环境优化策略时提供科学依据,本研究采用问卷调查法,从硬件设施、信息技术、教学法、医学智慧教室特色功能4个维度23项指标展开调查,采用KANO模型分析技术和满意度、重要度象限图对1 074份问卷进行数据分析。发现23项需求指标中,必备属性6项、期望属性7项、魅力属性9项、无差异属性1项。根据KANO模型理论重要度排序,智慧教室管理者应首先改善必备属性相关指标质量,优先提升期望属性相关指标质量,最后满足魅力属性相关指标需求。文章从学校顶层设计、教师和管理者3个层面提出了智慧教室相关政策和建设建议。 相似文献
96.
Quantification of motor deficit in Parkinson's disease with a motor performance test series 总被引:2,自引:0,他引:2
M. M. Pinter R. J. Helscher Ch. O. J. Nasel E. Riedl G. Schnaberth 《Journal of neural transmission (Vienna, Austria : 1996)》1992,4(2):131-141
Summary It was the purpose of the present study to quantify the expected motor deficit in parkinsonian patients with the computer assisted Motor Performance Test Series (MPS), version 05.87 by Schuhfried (1987) and to examine which of the motor test variables found correlate at a significance level of p<0.01 with items of motor examination recorded at neurological examination and activities of daily living of the Unified Parkinson's Disease Rating Scale (UPDRS), version 3.0.38 patients with idiopathic Parkinson's disease (PD) stages I–IV according to Hoehn and Yahr, aged 41 to 73 years were studied. The study design, i.e. initial rating by the physician followed immediately by testing of motor function with MPS was strictly adhered to in each patient.Physician's rating of rigor and the scores of the semiquantitative tests (finger taps, hand movements and alternating movements) as expression of hypokinesia and the activities of daily living correlated with the 3 factors of the Motor Performance Test Series at a highly significant level independent of disease stage. Tremor is only partly and never significantly reflected in the motor data measured. Stages I–II and II–IV (Hoehn and Yahr) differ significantly in the representative data of the Motor Performance Test Series.The results of the study support the assumption that MPS is a valid instrument for quantitative measurement of the motor deficit in parkinsonian patients, but that only some subtests are pathognomonic. 相似文献
97.
The effect of 9-tetrahydrocannabinol ( 9-THC) and alcohol, singly and in combination, on divided attention performance was investigated in cannabis users and non-users who were matched for alcohol use. Both cannabis and alcohol produced decrements in central and peripheral signal detections. Drug and alcohol effects were greater for signal presentations in the periphery. Cannabis users were less impaired in peripheral signal detection than non-users while intoxicated by cannabis and/or alcohol. These findings suggest the development of tolerance and cross-tolerance in regular cannabis users and/or the ability to compensate for intoxication effects. 相似文献
98.
目的 考察大学生韩剧收看情形,对韩国文化在认知、态度与行为层面的认同情形,以及大学生收看韩剧与韩国文化认同之间的关系.方法 采用访谈法、问卷法调查浙江师范大学380名学生.结果 92.2%大学生都收看过韩剧,收看情形相当普遍,剧情内容((x-)=3.92)、偶像演员的服装造型((x-)=3.78)和音乐等特性((x-)=3.29)是吸引大学生收看的主要原因.收看韩剧的大学生对韩国文化的认同程度颇高,以"向往韩国型"(t=-3.530,P<0.01)的认同类型居多.不同性别大学生在收看韩剧及对韩国文化认同上有显著差异(t=-3.537,P<0.01).收看韩剧与韩国文化的认同之间有显著相关(F=61.570,P<0.01).结论 多数大学生收看韩剧,但不会盲目模仿.韩剧传达的信息促使大学生对韩文化产生认同. 相似文献
99.
Emerging research has shown that sleepiness, defined as the tendency to fall asleep, is not only determined by sleep pressure and time of day, but also by physiological and cognitive arousal. In this study we evaluated (i) the impact of experimentally induced cognitive arousal on electroencephalogram (EEG) defined sleep latency, and subjective, somatic and cortical arousal, and (ii) whether experimentally induced cognitive arousal enhances performance on a driving simulator test. Twelve healthy sleepers each spent three nights and the following day in the sleep laboratory: an adaptation, a cognitive arousal and a neutral testing day. In the cognitive arousal condition, a visit of a television camera crew took place and subjects were asked to be interviewed. On each testing day, a 5-min heart rate recording, subjective sleepiness and arousal scales, Multiple Sleep Latency Test and a 25-min driving simulator task were scheduled three times at 2-h intervals. Experimentally induced cognitive arousal resulted in significant increases in objective sleep latency. Significantly elevated levels of subjective and somatic arousal--as indexed by a subjective arousal scale and heart rate--were also evidenced following cognitive arousal induction. A marginally significant trend for increased cortical arousal, measured by EEG beta activity, was also found. No effects were found on driving simulator performance. These findings support the concept of cognitive arousal as a significant component in determining sleep latency. In addition, it was illustrated that cognitively induced arousal can provoke increases in somatic and possibly even cortical arousal in normal sleepers. However, this was not accompanied by an enhanced ability to perform adequately on a driving simulator test. 相似文献
100.
Fallgatter AJ Esienack SS Neuhauser B Aranda D Scheuerpflug P Herrmann MJ 《Brain topography》2000,12(4):255-261
The P300-amplitude evoked with an acoustic oddball-paradigm is considered the most stable late event-related potential (ERP). This amplitude-index has become a standard parameter in electrophysiology. Recently, a robust ERP-parameter (NoGo-anteriorization, NGA) has been introduced, which reflects spatial brain electrical changes in relation to execution and inhibition of a motor response elicited with a Continuous Performance Test (CPT). The current study refers to the stability of this new topographical ERP-parameter compared to the stability of the classical P300-amplitude. For that purpose, 12 healthy subjects were investigated with both paradigms during recording of a 21-channel EEG. Analysis of the resulting ERPs revealed a very high stability for both, topographical and amplitude index: In every single subject, the brain electrical fields were characterized by a more anterior location in the NoGo- compared to the Go-condition (=NGA) and by higher amplitudes after target compared to distractor condition. T-tests, analyses of the effect size and of the power revealed equivalent differences between the two contrasting conditions for the topographical compared to the amplitude index. These results indicate that the stability of the topographical ERP-parameters elicited with the CPT is sufficient for an electrophysiological standard-index. The possibility to elicit a robust and specific spatial brain activation with the CPT is an ideal completion to the classical P300 amplitude effect and, therefore, hopefully will be a useful expansion of the standard paradigms in electrophysiological laboratories. 相似文献