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排序方式: 共有1058条查询结果,搜索用时 15 毫秒
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Visual versus computer evaluation of thiopental-induced EEG changes in temporal lobe epilepsy 总被引:1,自引:0,他引:1
J P Lieb M R Sperling J R Mendius C E Skomer J Engel 《Electroencephalography and clinical neurophysiology》1986,63(5):395-407
Thiopental-induced EEG beta activity was analyzed both visually and by computer in 33 patients with complex partial epilepsy. Studies were done in 16 patients with depth electrodes in limbic structures and 17 patients with scalp and sphenoidal electrodes. The percentage of drug-induced change in beta activity was quantified by computer using spectral analysis. The statistical significance of asymmetries between homologous sites in the amount of change was determined. The spatial distribution of significant asymmetries was used for localization and compared with the results of independent visual analysis of the thiopental EEG. Concordance between computer and visual evaluation occurred in 10 of 17 scalp/sphenoidal and 10 of 16 depth electrode tests. The accuracy of visual and computer localization was determined by comparing them with locus of itcal EEG onset, interictal spikes, and positron emission tomography. In scalp/sphenoidal studies, computer analysis indicating asymmetry appeared more likely to correlate with independent clinical criteria than visual analysis. In depth studies the reverse appeared to be true. Scalp/sphenoidal tests yielded positive results in 25-30% of patients whereas depth electrode tests were positive in 50-70% of patients. The results indicate that computer analysis of surface thiopental tests is an accurate and useful supplement to visual evaluation of these tests. 相似文献
3.
J J Sacks J L Herndon S H Lieb F E Sorhage L F McCaig D G Withum 《American journal of public health》1988,78(7):806-808
In the two-week period November 13-27, 1984, 12 patients died in a 54-bed nursing home in Florida; based on previous mortality patterns, 2.5 deaths would have been expected for the whole month. There was no similar increase in deaths in November 1984 and no comparable monthly death rate for any of 69 nursing homes in the same county from 1976-84. Comparison of the 12 deaths in November with 28 deaths that occurred during the previous 10 months and with 31 surviving patients who were continuously present in the nursing home between November 12-28, 1984 revealed that the patients who died in November were more likely to have had onset of the terminal event during the night shift, had a recent visitor, and had an admitting diagnosis of organic brain syndrome. The abrupt increase in the death rate for November 1984 was not associated with a measurable change in population characteristics, an outbreak of infectious disease, or changes in procedures or the environment. Reviews of employee schedules revealed a consistent and strong association between the duty times of two nurses and the onsets of the terminal episode and the times of patient deaths. Continuing epidemiologic surveillance of adverse outcomes in nursing homes is recommended. 相似文献
4.
Seeing the Light: Protein Theories of General Anesthesia 总被引:1,自引:0,他引:1
5.
Roselind Lieb Petra Zimmermann Robert H Friis Michael H?fler Sven Tholen Hans Ulrich Wittchen 《European psychiatry》2002,17(6):321-331
OBJECTIVE: Although somatoform disorders are assumed to be chronic clinical conditions, epidemiological knowledge on their natural course based on representative samples is not available. METHOD: Data come from a prospective epidemiologic study of adolescents and young adults in Munich, Germany. Respondents' diagnoses (N = 2548) at baseline and follow-up on average 42 months later are considered. The follow-up incidence, stability as well as selected baseline risk factors (sociodemographics, psychopathology, trauma exposure) for the incidence and stability of somatoform disorders and syndromes are prospectively examined. Diagnostic information was assessed by using the standardized Munich-Composite International Diagnostic Interview (M-CIDI). RESULTS: Over the follow-up period, incidence rate for any of the covered somatoform diagnoses was 25.7%. Stability for the overall group of any somatoform disorder/syndrome was 48%. Female gender, lower social class, the experience of any substance use, anxiety and affective disorder as well as the experience of traumatic sexual and physical threat events predicted new onsets of somatoform conditions, while stability was predicted by being female, prior existing substance use, affective and eating disorders as well as the experience of a serious accident. CONCLUSIONS: At least for a substantial proportion of individuals, the overall picture of somatization seems to be relatively stable, but with fluctuation in the symptom picture over time. Being female, the experience of substance use as well as anxiety disorder seem to constitute risk factors for the onset of new somatoform conditions as well as for a stable course over time. 相似文献
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Color Doppler imaging of the ocular ischemic syndrome. 总被引:12,自引:0,他引:12
A C Ho W E Lieb P M Flaharty R C Sergott G C Brown T M Bosley P J Savino 《Ophthalmology》1992,99(9):1453-1462
PURPOSE: This study describes hemodynamic characteristics of the ophthalmic, central retinal, and posterior ciliary arteries in 16 eyes of 11 patients with the ocular ischemic syndrome. Understanding the hemodynamic characteristics of the retrobulbar circulation may elucidate the natural history and pathophysiology of the ocular ischemic syndrome and perhaps form the basis for rational treatment of this condition. METHODS: Color Doppler imaging, a procedure that permits rapid noninvasive imaging of the ophthalmic, central retinal, and posterior ciliary arteries, was used to quantitate peak systolic blood flow velocities and vascular resistance (pulsatility index) within these vessels in study group eyes and in an age-matched control population. RESULTS: We demonstrated markedly reduced ocular ischemic syndrome central retinal and posterior ciliary artery peak systolic velocities compared with control group eyes. Central retinal and posterior ciliary artery vascular resistance (pulsatility index) was greater in ocular ischemic eyes versus control group eyes. Reversal of ophthalmic artery blood flow was detected in 12 of 16 ocular ischemic syndrome eyes. Study group eyes with poor vision had no detectable posterior ciliary arterial blood flow. CONCLUSION: Color Doppler imaging quantitates hemodynamic characteristics of the retrobulbar circulation in the ocular ischemic syndrome. There is markedly reduced peak systolic velocity and increased vascular resistance in ocular end arteries such as the central retinal and posterior ciliary arteries. Ophthalmic artery reversal of flow seems to represent collateral blood flow to lower resistance vascular beds. Posterior ciliary artery hypoperfusion may correlate with poor vision in the ocular ischemic syndrome. 相似文献
8.
Florida is third in the nation in the cumulative number of AIDS cases. The epidemic in the state has grown steadily since 1981, clustering initially in metropolitan South Florida but dispersing to other urban and nonurban areas. Heterosexually transmitted AIDS is fast increasing and is more than twice as common in Florida than the United States; however, homosexual/bisexual men and intravenous drug-using men and women continue to represent the majority of new cases. Special serologic studies of the prevalence of HIV infection provide a timely view of the dynamics and characteristics of the epidemic in various segments of the state's population. Data from a large, ongoing serosurvey suggest that about one in every 220 childbearing women is HIV-infected, a finding consistent with Florida's rank of second nationally in the number of pediatric AIDS cases. 相似文献
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10.
W. E. Lieb D. A. Merton J. A. Shields S. M. Cohen D. D. Mitchell B. B. Goldberg 《The British journal of ophthalmology》1990,74(5):305-308
Colour Doppler imaging (CDI) is a recent development in ultrasonography. It allows simultaneous two-dimensional structural imaging and Doppler evaluation of blood flow. Quantitative information on flow velocity is obtained by pulsed Doppler spectral analysis, the colour information being used to choose the vessel of interest. Using this technique the authors examined a patient with an orbital varix previously diagnosed by clinical findings and computed tomography. Dynamic evaluation with real-time direct imaging of flow facilitated the diagnosis of this orbital disorder without the need for any contrast material. This technique may prove to be a useful adjunct to computed tomography for the evaluation of suspected vascular lesions of the orbit. 相似文献