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81.
R F Peppard W R Martin G D Carr E Grochowski M Schulzer M Guttman P L McGeer A G Phillips J K Tsui D B Calne 《Archives of neurology》1992,49(12):1262-1268
Although cognitive impairment is commonly associated with Parkinson's disease, the relative importance of cortical and subcortical pathologic changes to the development of dementia is controversial. Characteristic abnormalities in cortical glucose metabolism have been reported previously in Alzheimer's disease, a disease in which cortical changes predominate. We measured cerebral glucose metabolism with positron emission tomography in 20 control subjects and in 14 patients with PD with mental status ranging from normal to severely demented to determine whether changes in cortical glucose metabolism occur in early PD and whether the degree and pattern of metabolic change relate to the severity of dementia. The patients were divided into demented and nondemented groups according to the results of neuropsychological assessment. Age-adjusted covariance analyses were performed, since the age distribution varied between groups. The nondemented patients with PD showed widespread cortical glucose hypometabolism without any selective temporoparietal defects. The pattern of glucose hypometabolism seen in the demented patients with PD resembled that described in patients with Alzheimer's disease; ie, there was a global decrease in glucose metabolism, with more severe abnormalities observed in the temporoparietal regions. 相似文献
82.
Psychogenic seizures can mimic convulsive epilepsy and with repetitive attacks, iatrogenic complications from aggressive treatment of status epilepticus can occur. We studied neuropsychiatric features of 20 patients in whom psychogenic seizures were intractable and at times continuous. Nineteen of 20 patients seen were female, and all but one were under 40 years of age. All had convulsive attacks resistant to various medications, normal neurological examinations, and negative imaging studies and electroencephalograms (EEGs). Sixteen had previous evidence of epilepsy and the other four had epileptic relatives. Seizures were atypically prolonged, included back arching and pelvic thrusting, and persisted despite intravenous diazepam and therapeutic phenytoin and phenobarbital levels. Seizures terminated spontaneously in five, were stopped by suggestion in four, and persisted until respiratory arrest or elective intubation in 11. Ten patients had conversion disorder, six borderline or mixed personality disorder and four mental retardation. Fifteen had had some precipitating stressor and the remainder had histories of exhibiting attention-seeking behaviour. Nine of 10 patients with conversion disorder had 'conversion V' Minnesota Multiphasic Personality Inventory (MMPI) profiles, while personality disorder patients had elevation of several psychopathological scales. Patients with conversion disorder gradually improved with anticonvulsant discontinuation, while retarded individuals were helped by behaviour modification, situational change or neuroleptics. Personality disorder patients continued to have attacks and eventually discontinued follow-up. Clinical evidence of non-epileptic seizures includes clinical atypicality and long duration, exacerbation by medications and frequent attacks despite normal examination and studies.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
83.
We conducted a study of the epidemiology of myasthenia gravis (MG) in four locations in central and western Virginia from 1970 through 1984. The population surveyed was 555,851 in 1984. A total of 73 new cases of MG occurred during the survey period, producing an overall average annual incidence rate of 9.1 per million. The point prevalence rate in 1980 was 13.4 per 100,000, and in 1984 it was 14.2. Approximately 15% of the population was black, and we found that incidence and prevalence rates for the black population were higher than the corresponding white population. When the population was subdivided into <50 and 50+ age groups, the incidence and prevalence were significantly higher in the older group. The rates we report here are higher than rates reported from any other locality. The reasons for the higher rates include optimal case identification, survey of a population with a higher incidence, and increasing aging of the population. 相似文献
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89.
Long-Term Clinical Outcomes Following Treatment of Actinic Keratosis with Imiquimod 5% Cream 总被引:2,自引:0,他引:2
Lee Peter K. MD PhD Harwell William B. MD † Loven Keith H. MD ‡ Phillips Tania J. MD § Whiting David A. MD res Kara L. MS # Lee James H. MD PhD # 《Dermatologic surgery》2005,31(6):659-664
BACKGROUND: The results from four phase III, randomized, vehicle-controlled studies showed that imiquimod 5% cream (imiquimod) was safe and effective in the treatment of actinic keratosis (AK). Patients applied imiquimod or vehicle cream to AK lesions on the face or balding scalp, dosing three times per week or two times per week for 16 weeks. OBJECTIVE: To obtain long-term safety follow-up data and estimate AK recurrence in patients who completely cleared their AK lesions in the treatment area at the 8-week post-treatment visit in the phase III studies. METHODS: One hundred forty-six patients from 30 study centers in the United States were evaluated for clinical evidence of AK, and safety data were collected. RESULTS: After a median follow-up period of 16 months, 24.7% (19 of 77) of the patients administered imiquimod three times per week and 42.6% (23 of 54) of the patients administered imiquimod two times per week had a recurrence of AK (the appearance of at least one AK lesion) in the original treatment area. The median number of AK lesions present was one lesion for both patients receiving imiquimod three times and those receiving imiquimod two times per week compared with a median of six lesions at baseline in the combined three times per week and two times per week phase III studies. There were no long-term safety issues, and the skin quality seen in the imiquimod-treated patients at the end of the phase III studies was maintained. CONCLUSION: One and a half years following treatment, imiquimod continued to provide a long-term clinical benefit in a majority of patients who experienced complete clearance of their AK lesions. 相似文献
90.
John F. Fraser MBChB ; Leila Cuttle BSc ; Margit Kempf BmedLSci ; Gael E. Phillips MBBS ; Peter K. O'Rourke PhD ; Kelvin Choo MBBS ; Mark T. Hayes PhD ; Roy M. Kimble MBChB 《Wound repair and regeneration》2005,13(2):189-197
Early to mid-term fetuses heal cutaneous incisional wounds without scars; however, fetal response to burn injury has not been ascertained. We present a fetal model of thermal injury and subsequent analysis of fetal and lamb response to burn injury. A reproducible deep dermal burn injury was created in the fetus by application of water at 66 degrees C for 7 seconds, and at 82 degrees C for 10 seconds to the lamb. Macroscopically, the area of fetal scald was undetectable from day 7 post injury, while all lamb scalds were readily identified and eventually healed with scarring. Using a five-point histopathology scoring system for alteration in tissue morphology, differences were detected between control and scalded skin at all stages in lamb postburn, but no difference was detected in the fetal model after day 7. There were also large differences in content of alpha-smooth muscle actin and transforming growth factor-beta1 between control and scalded lamb and these differences were statistically significant at day 14 (P < 0.01). This novel model of fetal and lamb response to deep dermal injury indicates that the fetus heals a deep burn injury in a scarless fashion. Further elucidation of this specific fetal process of burn injury repair may lead to improved outcome for patients with burn injury. 相似文献