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81.
A Z Zeman D Kidd B N McLean M A Kelly D A Francis D H Miller B E Kendall P Rudge E J Thompson W I McDonald 《Journal of neurology, neurosurgery, and psychiatry》1996,60(1):27-30
OBJECTIVES--To determine whether oligoclonal band (OCB) negative multiple sclerosis is a reliable diagnosis and, if so, whether it has a distinctive prognosis. METHODS--Retrospective and matched prospective comparison of the clinical and laboratory features of patients with clinical definite multiple sclerosis with and without intrathecal synthesis of oligoclonal IgG. RESULTS--Thirty four patients were identified with apparent OCB negative clinically definite multiple sclerosis. The results of oligoclonal banding proved to have been equivocal in 14 of 34; the clinical diagnosis of multiple sclerosis was questionable in 8 of 34. The remaining 12 patients with "true" OCB negative multiple sclerosis were significantly less disabled than matched OCB positive controls. Re-examination of CSF-serum pairs from six OCB negative patients showed that three remained OCB negative while three showed evidence of intrathecal synthesis of OCBs. CONCLUSIONS--OCB negative clinically definite multiple sclerosis is rare and should be diagnosed with caution; in unequivocal cases it seems to have a relatively benign prognosis. 相似文献
82.
Diagnostic imaging technologies are essential in health care but have high costs and poorly defined benefits. Formulation and implementation of policy on their procurement and use is made difficult by the complexity of the diagnostic process, and the limitations of available data and assessment methodology. Informed policy decisions will need to be based on a synthesis of imperfect data from a variety of perspectives, and supplemented by effective dissemination and feedback of information. A list of attributes for consideration in the policy formulation process is presented. 相似文献
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86.
During April to November 1986 and May to October 1987, a systematic survey of patterns of use of alcohol, kava, tobacco and analgesics by Northern Territory Aboriginal people aged 15 years and older was conducted. The objectives of the study were to ascertain the prevalence of drug use, the frequency of drug use and the quantity of drugs used. In addition, information about Aboriginal people's perceptions of the drugs, their beliefs about drug use and the value of drugs in their culture was collected. This paper describes only the quantitative aspects of drug use of this population. A stratified sampling procedure was used to sample 10 per cent of the target population. Using two survey instruments, an individual questionnaire and a group questionnaire, data were gathered from 1764 Aboriginal people living in the Northern Territory. As a whole, the Northern Territory Aboriginal people have a drug consumption pattern quite distinct from urban Australians. 相似文献
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88.
Malignant transformation of a Hürthle cell tumor: case report and survey of the literature 总被引:1,自引:0,他引:1
R J McDonald S Y Wu J L Jensen L N Parker K P Lyons E M Moran W H Blahd 《Journal of nuclear medicine》1991,32(6):1266-1269
Hürthle cell carcinoma is a relatively uncommon type of well-differentiated thyroid carcinoma. Its diagnosis has been controversial due to the difficulty in separating Hürthle cell adenoma from Hürthle cell carcinoma, thus the term Hürthle cell tumor is often used to describe both lesions. The present case of anaplastic giant-cell carcinoma in an 81-yr-old woman arose in a Hürthle cell tumor. This case illustrates the propensity of Hürthle cell tumor to undergo "malignant transformation" and argues for a more aggressive approach to such tumors. 相似文献
89.
I. Bertoncello T. R. Bradley J. J. Campbell A. J. Day I. A. McDonald G. R. McLeish M. A. Quinn R. Rome G. S. Hodgson 《British journal of cancer》1982,45(6):803-811
114 biopsy specimens from 70 patients with ovarian carcinoma at all stages of disease were submitted for assessment of clonogenic capacity in agar. A highly significant correlation was found between agar clonogenicity and patient survival after biopsy. However, problems related to inherent tumour heterogeneity, quality of sample and tissue disaggregation indicate that this technique may have limited applicability in the routine assessment of patients. Only 41 biopsy specimens (36%) from 31 patients (44.3%) complied with the prerequisite criteria for agar clonogenic assessment, namely: (a) the confirmed presence of malignant cells in the biopsy, (b) the ability to prepare a single-cell suspension, and (c) adequate viable cell numbers for assay. Furthermore, although the dominant patterns of agar clonogenic growth could be identified and correlated with stage of disease, the heterogeneity in both initial clonogenic capacity and "self-renewal" capacity assessed by the ability of primary clones to propagate in liquid culture and reclone in agar was too inconsistent for the assay to be used as a prognostic index for the individual patient. 相似文献
90.
A J McDonald 《The Journal of comparative neurology》1982,212(3):293-312
Neurons in the lateral and basolateral nuclei of the rat amygdala were studied using Golgi-Kopsch and rapid Golgi techniques. According to differences in perikaryal, dendritic, and axonal morphology, three main neuronal classes are recognized. Class I neurons, the predominant cell type in both nuclei, are large, spiny neurons that vary in size in different subdivisions of the lateral and basolateral nuclei. These neurons often have a pyramidal shape, exhibiting one or two thick "apical" dendrites and several thinner "basal" dendrites. Axons of class I neurons, which appear to pass out of the nucleus of origin, usually give off several collaterals that arborize modestly in the vicinity of the cell. Class II neurons are smaller, ovoid cells that comprise approximately 5% of impregnated neurons. These neurons are characterized by spine-sparse dendrites and fairly dense local axonal arborizations. Class II neurons may be classified as multipolar, bitufted, or bipolar, depending on dendritic branching pattern. Another type of class II neuron, the amygdaloid chandelier cell, is recognized by virtue of its distinctive axon. The chandelier cell axon gives off numerous collaterals that form nestlike entanglements exhibiting clusters of axonal varicosities. Isolated chandelierlike axons of undetermined origin were observed forming multiple contacts with initial segments of class I axons. Several small, spherical class III neurons with short, varicose dendrites were observed. Axons branch profusely to form a dense tangle of collaterals in the vicinity of the cell. Both axons and dendrites establish numerous contacts with class I dendrites. This investigation, the first detailed Golgi study of the basolateral amygdala of the rat, reveals that the cytoarchitecture of this brain region in the rat is basically similar to that of the opossum and other mammals. Morphologic details described in this report should be useful in the interpretation of ultrastructural, immunocytochemical, and electrophysiological studies of the basolateral amygdala. 相似文献