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81.
The effects of caffeine and aspirin on mood and performance 总被引:1,自引:0,他引:1
H R Lieberman R J Wurtman G G Emde I L Coviella 《Journal of clinical psychopharmacology》1987,7(5):315-320
Caffeine, in addition to being a food constituent, is also a common analgesic adjuvant that is used in combination with aspirin in certain over-the-counter preparations. Caffeine has previously been shown to significantly improve certain aspects of human performance, particularly sustained vigilance, when administered in low and moderate doses (32 to 256 mg). We therefore attempted to determine whether caffeine, in the dose (64 mg) found in some over-the-counter drugs, retains this beneficial property when combined with aspirin. We also measured self-reported mood state, using various standardized questionnaires, since caffeine has been reported to have both beneficial and adverse effects on alertness and anxiety. We observed that caffeine (64 mg), when added to aspirin (800 mg), significantly improves vigilance performance and increases self-reported efficiency when compared with either placebo or aspirin alone. As previously reported, this caffeine dose alone significantly increased vigilance and decreased reaction time. No adverse effects of caffeine were detected on any of the parameters that were assessed. This study therefore demonstrated that the addition of caffeine to aspirin, in a dose commonly employed in over-the-counter drugs, has significant beneficial consequences with respect to mood and performance. 相似文献
82.
G. J. F. Brekelmans W. van Emde Boas D. N. Velis F. H. Lopes da Silva P. C. van Rijen C. W. M. van Veelen 《Epilepsia》1998,39(12):1290-1301
Summary: purpose: The yield of subdural versus intracerebra1 electrodes for ictal localization remains a point of controversy. We assessed the relative sensitivity of these two types of electrodes per case. Methods: Eighty-three intracranial recordings obtained from 82 patients were retrospectively reviewed to establish which type of electrode performed best in which patients and which seizure types. Results: Sixty (73%) of 82 patients had temporal lobe seizure onsets, eight frontal, nine widespread or multifoca/multilobar or both, whereas in five, seizure onset was not localized. Exclusive use of intracerebral electrodes would have been sufficient for accurate localization of the seizure—-onset zone in all 35 patients with strictly mesial temporal seizure onsets. In only 20 (57%) of these 35 patients, the same decision would have been reached with exclusive use of subdural electrodes. In wide-spread neocortical and mesial temporal seizures (n = 25). yield of both electrode types was at about the same level, but neither was sufficient to identify the zone of ictal onset on its own. In frontal or multilobar seizures (n = 22), yield of subdural electrodes was slightly better then that of the intracerebral electrodes, but was not sufficient in all cases. Conclusions: This study indicates that, depending on the characteristics of the seizure disorder, exclusive use of either intracerebral or subdural electrodes may easily result in erroneous diagnosis because of insufficient sampling of the brain. These findings are in contrast with other studies emphasizing the high yield of reliable EEG findings in evaluations with a single type of electrode and corroborate the results of one of our previous studies. 相似文献
83.
Lethal blockage of a Bj?rk-Shiley artificial heart valve caused by strut fracture--the metallurgical aspect 总被引:1,自引:0,他引:1
The fracture of the outlet strut of a Bj?rk-Shiley artificial heart valve implanted in a 21 year old man lead--6 years after the operation--to the valve disc jamming closed with a resulting lethal heart failure and circulation standstill. The probable cause of the valve strut fracture could be determined by metallurgical/metallographical investigation of the material and the production methods. 相似文献
84.
This essay explores implications of current trends in developmental science for understanding psychopathology at the dawn of the new millennium. Over the past half century, it has become clear that uniform and general principles of development (i.e., those that are applicable at all times, to all people, and in all places) will be of limited utility in understanding the processes of greatest interest in development and psychopathology. Instead, such processes are characterized by complexly organized individuals engaged in developmental transactions within multiple contexts (ranging from the biological environment of neurons to the cultural systems of meaning that shape people's lives). These transactions in turn often yield variable outcomes. In order to portray how we have come to this conclusion, we first provide a view of contemporary research in three areas of early development: the biology of the developing brain, the complexities of early emotional development, and the cultural contexts of child development. We then trace how an increasing appreciation of organized complexity, developmental transactions, and the meaning of context have played out in the emerging field of infant mental health before closing with our vision of new opportunities for the study of experience in the midst of variation. 相似文献
85.
False aneurysms of the left ventricle develop after rupture of the ventricular wall in an area of pericardial adhesions. This complication of myocardial infarction is uncommon. Images of a post-infarction false aneurysm are presented. 相似文献
86.
Outcome prediction models on admission in a medical intensive care unit: do they predict individual outcome? 总被引:3,自引:0,他引:3
J H Sch?fer A Maurer F Jochimsen C Emde K Wegscheider H R Arntz J Heitz B Krell-Schroeder A Distler 《Critical care medicine》1990,18(10):1111-1118
Prospectively acquired data from 941 patients staying greater than 24 h in a medical ICU were analyzed to determine the relevance of scoring on ICU admission by the following methods of outcome prediction: Acute Physiology and Chronic Health Evaluation (APACHE II), Simplified Acute Physiology Score (SAPS), and Mortality Prediction Model (MPM). Analysis was performed separately for all patients (group A) and for a subsample (group B), obtained by excluding coronary care patients. Calculation of risk and classification of patients were carried out as recommended in the literature for MPM, APACHE II, and SAPS. In group A, sensitivities (correct prediction of hospital mortality) were 44.7%, 51.1%, and 21.2% and specificities (correct prediction of survival) were 84.5%, 85.4%, and 96.8%, respectively; overall correct classification rates were 73.3%, 75.8%, and 75.6%. In group B, sensitivities were slightly higher, but total correct classification rates did not reach group A levels. Goodness-of-fit testing showed low levels of fit for all methods in both groups. Application of APACHE II to diagnostic subgroups, using disease-adapted risk calculations, revealed marked inconsistencies between the estimated risk and the observed mortality. We conclude that the estimation of risk on admission by the three methods investigated might be helpful for global comparisons of ICU populations, although the lack of disease specificity reduces their applicability for severity grading of a given illness. The inaccuracy of these methods makes them ineffective for predicting individual outcome; thus, they provide little advantage in clinical decision-making. 相似文献
87.
88.
Both a sleep-wakefulness cycle and a basic rest-activity cycle were observed in 20 normal infants left undisturbed for ten hours following birth. Behavioral wakefulness occurred immediately following delivery and in between sleep periods despite the lack of feeding and other intervention. Medication given to mothers during labor resulted in decreased amounts of infant wakefulness and increased amounts of quiet (non rapid eye movement) sleep. 相似文献
89.
Out of a group of patients suffering from a spontaneous subarachnoid hemorrhage 27 patients were checked by computer-assisted tomography (CAT), 23 patients by radioisotope cisternography, and 21 patients by both diagnostic procedures. The results were correlated with the clinical observations. The flow of the CSF was normal in 7 patients (30.43%), and pathological in 16 patients (69.56%). Of the 27 patients checked by CAT, 23 (85.18%) showed a ventricular dilatation, which in 17 patients (62.96%) was not connected with a corresponding increase of the cisterns of the convexity. The clinical symptoms of hydrocephalus, the degree of impairment of the circulation of the CSF determined by radioisotope cisternography and the ventricular diameter as determined by CAT correlated well. 相似文献
90.
Summary CT cisternography and CSF scintigraphy are indispensable in the detailed morphologic and etiologic evaluation of special types of childhood hydrocephalus. In addition these investigations afford interesting insights into CSF dynamics in apparently complete membranous or tumorous obstruction of the fourth ventricle and into the genesis of internal hydrocephalus in cerebellopontine angle tumors. 相似文献