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SUMMARY. There are no current U.K. or international guidelines or regulations covering the production, processing and storage of haemopoietic cells such as to allow their engraftment following myeloablative therapy. This paper seeks to provide such guidelines. It enumerates how quality control and assurance can be applied to this area of transfusion medicine; procedural steps relating to bone marrow harvest on peripheral blood stem cell collection are outlined and recommended doses of nucleated cells suggested for both procedures. General specifications for identification, storage and transportation of bone marrow and peripheral blood stem cells are included and specific laboratory procedures related to the provision of haemopoietic cells for engraftment are outlined. Umbilical cord blood transplants and long-term bone marrow culture are alluded to but these are still in a research phase.  相似文献   
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PURPOSETo analyze the MR characteristics of a series of patients with esthesioneuroblastoma and discuss the typical surgery and its postoperative MR appearance.METHODSThe MR studies of 15 patients with the pathologic diagnosis of esthesioneuroblastoma (also known as olfactory neuroblastoma) were retrospectively reviewed and correlated with CT and surgical findings. The postoperative MR studies of 10 patients who underwent craniofacial resection were also reviewed.RESULTSIn all cases the tumors arose in the superior nasal cavity and extended into the ethmoid cells. In some instances the tumors extended into the other paranasal sinuses, orbits, anterior cranial fossa, and cavernous sinus. The tumors were typically expansile and destructive in their growth patterns. Compared with brain gray matter, the tumors were hypointense on T1-weighted images and isointense to hyperintense on T2-weighted images. Nine tumors were heterogeneous and 6 were homogeneous. Contrast enhancement ranged from mild to marked. MR was useful for characterizing the various tissues and distinguishing fluid in the postoperative nasal cavity.CONCLUSIONSEsthesioneuroblastoma, although an uncommon tumor, may be suspected in lesions of the superior nasal cavity demonstrating both expansile and destructive growth properties. The MR findings are otherwise nonspecific. MR is the imaging modality of choice for depicting local tumor extension and evaluating for recurrence after craniofacial resection.  相似文献   
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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   
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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   
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The epidemiology of myasthenia gravis in central and western Virginia.   总被引:4,自引:0,他引:4  
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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