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排序方式: 共有10000条查询结果,搜索用时 46 毫秒
991.
K Itoh K Nishimura K Togashi I Fujisawa Y Nakano H Itoh K Torizuka 《Journal of computer assisted tomography》1986,10(5):831-835
Four patients with cavernous hemangioma of face and neck were evaluated with magnetic resonance imaging. Pathologically, soft tissue cavernous hemangiomas are characterized by small feeding arteries and large blood poolings. Arteriography usually fails to demonstrate the extent of the lesion. Computed tomography does not allow differentiation between these lesions and surrounding normal tissues. Magnetic resonance clearly demonstrates hemangiomas with good contrast between lesion and normal tissues. Spin-echo technique with long echo time appears to be particularly useful to delineate these lesions. 相似文献
992.
Periodic lateralized epileptiform discharges (PLEDs): a possible role for metabolic factors in pathogenesis 总被引:1,自引:0,他引:1
Periodic, lateralized, epileptiform discharges (PLEDs) in the electroencephalogram have been reported in association with a variety of structural lesions of the brain. Although a great deal of attention has been directed to the neuropathological basis of PLEDs, little emphasis has been placed on the functional basis of this EEG syndrome. In this paper, we reported a patient with multiple systemic problems whose EEG showed PLEDs. However, radiological and pathological studies revealed no neuropathological basis for the occurrence of this EEG syndrome. Thus, we presented evidence that metabolic factors may play a part in the pathogenesis of PLEDs. 相似文献
993.
994.
Radionuclide thyroid imaging was performed in 872 consecutive patients with hyperthyroidism. Of these, 84% were found to have diffuse toxic hyperplasia (Graves' disease), while 12% had autonomously functioning nodules (Plummer's disease), 3% had Graves' disease developing in a multinodular gland, and in the remaining 1%, either a clear diagnosis could not be established or the hyperthyroidism was due to thyroiditis or the Jod-Basedow phenomenon. It was found that a thyroid scan seldom provides additional diagnostic information in patients with Graves' disease when a diffuse goitre is present. However, if patients are to be treated with radioiodine (131I), thyroid imaging with tracer quantitation can replace a 24-h 131I uptake measurement, this having the advantages that the patients are required to attend only once, and that the gland size can be measured. In addition, visual confirmation of tracer uptake by the thyroid is obtained and patients with thyroiditis will not receive inappropriate therapy. When single or multiple thyroid nodules are palpated, a thyroid scan is crucial in establishing an accurate diagnosis, as it is not otherwise possible to differentiate between Plummer's disease and Graves' disease developing in a multinodular gland. Indeed, in 20 of our 63 patients (32%) with single autonomously functioning nodules, the initial clinical assessment had been incorrect. 相似文献
995.
One hundred sixty-two white-blood-cell scans were retrospectively reviewed to determine the sensitivity and specificity of the test for pulmonary and pleural infection. All scans were performed 18-24 hr after injection of indium-111 oxine-labeled autologous or donor cells. Pulmonary activity was graded on a scale of 0-4: 0 = equal to soft tissue; 1 = greater than soft tissue but less than rib; 2 = equal or greater than rib but less than liver; 3 = equal or greater than liver but less than spleen; 4 = equal to spleen. Activity was also characterized as being focal or diffuse. The white-blood-cell scan findings were correlated with the clinical diagnosis on the basis of physical examination, laboratory results, chest radiographs, clinical course, and pathologic studies when available. As pulmonary activity increased from grade 1 to 4, sensitivity declined from 93% to 14% and specificity increased from 64% to 100%. The sensitivity and specificity of focal uptake were 31% and 89% vs 62% and 74% for diffuse pulmonary activity. Making a distinction between focal and diffuse activity did not improve the specificity of low grades of pulmonary activity. The white-blood-cell scan can be very sensitive or very specific for pulmonary or pleural infection, depending on the criteria selected for a positive scan. 相似文献
996.
The results of parenteral treatment with Etaretin in 40 patients (79 eyes) suffering from senile maculopathy are reported. In 84% of the cases there was a degeneration of the dry type and in 16% a disciform exudative maculopathy. The cases of dry maculopathy responded well within a floow-up period of 8 to 18 months. 相似文献
997.
998.
Variability of antigenicity/allergenicity in different strains of Alternaria alternata 总被引:1,自引:0,他引:1
I Steringer L Aukrust R Einarsson 《International archives of allergy and applied immunology》1987,84(2):190-197
Biochemical and immunological properties were studied in crude mould extracts from 10 different strains of Alternaria alternata. The mould strains were grown on completely synthetic medium and harvested under identical conditions. The biochemical and immunological analyses (protein content, carbohydrate content, IEF, RAST-inhibition, CIE/CRIE and the content of a major allergen) showed significant variations between the individual strains of A. alternata. 32 antigens were identified in the CIE pattern of A. alternata and 19 different allergens were identified in CRIE analysis (1 major, 7 intermediate and 6 minor allergens). There was a significant variation in the content of the major A. alternata allergen (Ag-8, partially identical to Alt-I) between the different individual strains. Furthermore, a considerable variation in the content of Ag-8 was observed for a specific strain cultivated at different occasions under identical cultivation conditions during a time period of 3 years. 相似文献
999.
L. N. Grushevskaya B. M. Pyatin O. B. Stepanenko N. I. Avdyunina V. P. Lezina V. I. Prokof’eva 《Pharmaceutical Chemistry Journal》2007,41(8):440-443
Cardiocyclide, a new Russian class III antiarrhythmic agent, was developed at the State V. V. Zakusov Science Research Institute
Pharmacology, Russian Academy of Medical Sciences. The aims of the present work were to study the physicochemical properties
of the hydrochloride salt of this agent (N1-(3-diethylaminopropyl)-N1-(p-nitrobenzoyl)aminoacetic acid N,N-dicyclohexylamide HCl) and to develop an analytical method for this compound. IR, 1H NMR, and UV spectra were obtained for cardiocyclide; its solubility was studied; its melting temperature, weight loss on
drying and the transparency, color, and pH of its solutions were determined. The purity of material containing compound I
was determined by thin-layer chromatography; quantitative cardiocyclide contents were estimated by non-aqueous titration.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 8, pp. 42–45, August, 2007. 相似文献
1000.