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91.
Focal Alzheimer's disease 总被引:1,自引:0,他引:1
Alzheimer's disease is characterized by relative sparing of primary sensory and motor cortex and a lack of sensory or motor symptomatology. We report a case of presenile onset dementia accompanied by a slowly progressive hemiparesis. Autopsy examination showed severe pathologic involvement of somatosensory cortex with neuritic plaques and neurofibrillary tangles, in addition to degeneration of the nucleus basalis and locus ceruleus. Neurochemical and immunocytochemical studies showed a moderate cortical cholinergic deficiency with normal somatostatin-like immunoreactivity and a profuse immunostaining of somatosensory cortex with the Alz-50 antibody. These unusual features emphasize that Alzheimer's disease is extremely variable in its clinical symptomatology, pathologic distribution, and neurochemical dimensions. 相似文献
92.
93.
E M Martin L C Robertson H E Edelstein W J Jagust D J Sorensen D San Giovanni V A Chirurgi 《Journal of clinical and experimental neuropsychology》1992,14(5):857-868
HIV-seropositive and seronegative control subjects performed a standard paper-and-pencil version and an experimental reaction time version of the Stroop Color-Word Naming Task. Results indicated that both symptomatic and asymptomatic HIV-positive subjects showed an exaggerated Stroop effect compared to controls, but this increase was only apparent on the RT version of the task. Analysis of components of the effect indicated that HIV-positive subjects showed increased inhibition compared to controls but normal facilitation. These results suggest that HIV-related cognitive slowing has an attentional component, most likely involving controlled processes. In addition, these results emphasize the utility and sensitivity of RT measures in the study of early HIV-1 infection. 相似文献
94.
Sjors FPJ Coppus Jose I Emparanza Julie Hadley Regina Kulier Susanne Weinbrenner Theodoros N Arvanitis Amanda Burls Juan B Cabello Tamas Decsi Andrea R Horvath Marcin Kaczor Gianni Zanrei Karin Pierer Katarzyna Stawiarz Regina Kunz Ben WJ Mol Khalid S Khan 《BMC medical education》2007,7(1):1-10
Background
Little research has been conducted to investigate role stress experienced by faculty members in medical schools in developing countries. This becomes even more important when the process of reform in medical education has already taken place, such as the case of Iran. The objectives of this study were to investigate and assess the level and source of role-related stress as well as dimensions of conflict among the faculty members of Iranian medical schools. Variables like the length of academic work, academic rank, employment position, and the departments of affiliation were also taken into consideration in order to determine potentially related factors.Methods
A survey was conducted at three different ranks of public medical schools. The validated Organizational Role Stress Scale was used to investigate the level of role stress and dimensions of role conflict among medical faculty members. The response rate was 66.5%.Results
The findings show that role stress was experienced in high level among almost all faculty members. All three studied medical schools with different ranks are threatened with relatively the same levels of role stress. Specific differences were found among faculty members from different disciplines, and academic ranks. Also having permanent position and the length of services had significant correlation with the level of role stress. The major role- related stress and forms of conflict among faculty members were role overload, role expectation conflict, inter-role distance, resource inadequacy, role stagnation, and role isolation.Conclusion
The most role-related stressors and forms of conflict among faculty members include too many tasks and everyday work load; conflicting demands from colleagues and superiors; incompatible demands from their different personal and organizational roles; inadequate resources for appropriate performance; insufficient competency to meet the demands of their role; inadequate autonomy to make decision on different tasks; and a feeling of underutilization. The findings of this study can assist administrators and policy makers to provide an attractive working climate in order to decrease side effects and consequences of role stress and to increase productivity of faculty members. Furthermore, understanding this situation can help to develop coping strategies in order to reduce role-related stress. 相似文献95.
96.
Role of positron emission tomography in determining the extent of CNS ischemia in patients with sickle cell disease 总被引:1,自引:0,他引:1
Nearly 25% of patients with sickle cell disease (SCD) experience central nervous system morbidity involving both large and small vessel disease. Optimal imaging methods for determining the extent of ischemia are not known. Positron emission tomography (PET) has the unique ability to show tissue function as well as structure. Reports concerning patients with non-SCD neurodegenerative disorders suggest PET may be useful in determining prognosis. We compared magnetic resonance imaging, magnetic resonance angiography, and neuropsychological testing with PET prospectively. Six patients with SCD and a history of stroke, aged 10 to 28, were enrolled. PET studies were performed on an ECAT HR 47 scanner (Siemens/CTI, Knoxville, TN) using 18-F-fluorodeoxyglucose as a tracer. PET interpretations were conducted in blinded fashion. MRI studies found two patients with only small vessel disease and four with both large and small vessel disease. In two of four subjects with large vessel disease, PET showed a corresponding metabolic abnormality and also identified an area of hypometabolism extending beyond the anatomical lesion as shown by MRI. PET did not demonstrate an abnormality corresponding with small vessel disease. Detailed neuropsychological testing demonstrated cognitive dysfunction in all cases. For some patients, PET may add sensitivity in detecting impaired metabolism in the area surrounding a major vessel infarct. However, the technique does not appear to be generally useful in characterizing small watershed or deep white matter infarcts. Larger studies, to include control subjects and carefully selected untransfused SCD patients, are needed. A combination of conventional imaging and neuropsychological testing remains the preferred evaluation for most SCD patients with neurologic symptoms. 相似文献
97.
SL Dorman SM Graham J Paniker S Phalira WJ Harrison 《Malawi medical journal : the journal of Medical Association of Malawi》2014,26(4):119-123
Background
BEIT CURE International Hospital (BCIH) opened in 2002 providing orthopaedic surgical services to children in Malawi. This study reviews the hospital''s progress 10 years after establishment of operational services. In addition we assess the impact of the hospital''s Malawi national clubfoot programme (MNCP) and influence on orthopaedic training.Methods
All operative paediatric procedures performed by BCIH services in the 10th operative year were included. Data on clubfoot clinic locations and number of patients treated were obtained from the MNCP. BCIH records were reviewed to identify the number of healthcare professionals who have received training at the BCIH.Results
609 new patients were operated on in the 10th year of hospital service. Patients were treated from all regions; however 60% came from Southern regions compared with the 48% in the 5th year. Clubfoot, burn contracture and angular lower limb deformities were the three most common pathologies treated surgically. In total BCIH managed 9,842 patients surgically over a 10-year period. BCIH helped to establish and co-ordinate the MNCP since 2007. At present the program has a total of 29 clinics, which have treated 5748 patients. Furthermore, BCIH has overseen the full or partial training of 5 orthopaedic surgeons and 82 orthopaedic clinical officers in Malawi.Conclusion
The BCIH has improved the care of paediatric patients in a country that prior to its establishment had no dedicated paediatric orthopaedic service, treating almost 10,000 patients surgically and 6,000 patients in the MNCP. This service has remained consistent over a 10-year period despite times of global austerity. Whilst the type of training placement offered at BCIH has changed in the last 10 years, the priority placed on training has remained paramount. The strategic impact of long-term training commitments are now being realised, in particular by the addition of Orthopaedic surgeons serving the nation. 相似文献98.
W. J. Jagust M. N. Haan J. L. Eberling N. Wolfe B. R. Reed 《Journal of neuroimaging》1996,6(3):156-160
Eighteen patients with Alzheimer's disease were studied with positron emission tomographic measurements of regional cerebral metabolism of glucose. All patients were initially diagnosed and evaluated, underwent positron emission tomography, and then were followed with annual reevaluations, at which time the Mini-Mental State Examination (MMSE) was performed. Patients were followed for an average of 2.5 years, and the rate of cognitive decline was calculated by determining the rate of change in the MMSE score defined as the MMSE score at the initial evaluation minus the MMSE score at the last examination, divided by the number of months between testing. The regional cerebral metabolic rates for glucose determined at the time of the first MMSE were then regressed on these changes in scores. Results showed that glucose metabolic rates in posterior temporal and primary visual cortex regions were significantly correlated with the subsequent rate of cognitive deterioration. These associations were not confounded by age, length of follow-up, baseline MMSE score, or education. Stratification on gender suggested that these associations were much stronger in women than in men. These results replicate previous findings showing that functional brain imaging is predictive of the rate of cognitive decline in Alzheimer's disease. 相似文献
99.
100.
WJ Meyler 《Cephalalgia : an international journal of headache》1996,16(1):5-10
Ergotamine has been used for many years in the treatment of migraine, although there is little formal clinical evidence that it is significantly more efficacious than placebo. A number of side effects associated with ergotamine have been reported in the literature, including myocardial infarction, ischaemia of limb extremities, and fibrotic changes. Long-term use has led to reported cases of ergotamine-induced headache, vascular reactivity, and subclinical ergotism. When the safety profile of this drug is considered, coupled with its debatable efficacy from a clinical review previously published, the resulting poor risk: benefit ratio brings into question the continued use of ergotamine as a migraine treatment and calls for better controlled trials of its efficacy, or lack of, in the acute treatment of migraine. 相似文献