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991.
992.
In situ localization of HuHF serine protease mRNA and cytotoxic cell-associated antigens in human dermatoses. A novel method for the detection of cytotoxic cells in human tissues. 总被引:5,自引:3,他引:2 下载免费PDF全文
G. S. Wood C. Mueller R. A. Warnke I. L. Weissman 《The American journal of pathology》1988,133(2):218-225
Human Hanukah Factor (HuHF) is a trypsinlike serine protease associated with cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells. Employing a radiolabeled RNA probe for the HuHF gene, cells containing HuHF mRNA in situ were detected in skin lesions from patients with a variety of reactive and neoplastic dermatoses including positive allergic contact dermatitis patch tests, lichen planus, erythrodermic psoriasis, Sezary syndrome, and poikilodermatous mycosis fungoides. The results were correlated with in situ studies of CTL/NK subsets as defined immunohistologically by a panel of monoclonal antibodies applied to sermiserial sections of the same tissue blocks used for the HuHF hybridizations. The results suggest that cytotoxic cells are present in each of these dermatoses, that they may be situated within either the epidermis or the dermis, and that they belong predominantly to the CTL subset because Leu-7+ or CD16+ cells (NK cells) were typically rare or absent. A variable proportion of cells expressed Leu-19 antigen (a marker for non-MHC-restricted cytotoxic cells); however, its rarity in several cases suggests that most of the HuHF+ cells identified in them belonged to the MHC-restricted, Leu-19- CTL subset. It is concluded that the correlation of molecular biologic and immunohistologic data will be a useful method for the further characterization of cytotoxic cell subsets in human dermatoses. 相似文献
993.
994.
Osteoid-osteoma of the spine with localization aided by 99 mTc-polyphosphate bone scan. Case report.
This is a case report of a 13-year-old boy with an osteoid-osteoma located in the pedicle of the third lumbar vertebra. The lesion could not be visualized on routine roentgenograms but with the use of technetium polyphosphate bone scan as a guide a suggestive bone lesion was found with tomograms. Histologic examination confirmed the diagnosis of osteoid-osteoma. This case illustrates the value of skeletal scanning in occult bone lesions. 相似文献
995.
A number of 3-amino-2-benzhydrylquinuclidines were tested for diuretic activity in both rats and dogs. The Schiff base formed from 2-benzhydryl-3-quinuclidinone and benzylamine was reduced with NaBH4 to a mixture of isomers, the cis isomer being preponderants. cis-2-Benzhydryl-3-benzylaminoquinuclidine was isolated by chromatography and debenzylat:d to cis-3-amino-2-benzhydrylquinuclidine, the most active compound in this series. The corresponding trans isomer was considerably less active. It was made by reacting the mesylate of cis-2-benzhydr-l-3-quinuclidinol with Nan3 to form trans-3-azido-2-benzhydrylquinuclidine which was reduced with LiAlH4. In dose-response studies (sodium excretion as a function of dose) in rats the maximal or ceiling effect of cis-3-amino-2-benzhydrylquinuclidine was considerably greater than that of hydroflumethiazide but less than that of furosemide. An unusual biphasic dose-response was seen in dogs with cis-3-amino-2-bezhydrylquinuclidine, centering around 10 mg/kg. 相似文献
996.
997.
J S Nagel M Ichise S P Mueller K A Johnson R J English W D Kaplan O Schober B L Holman 《Archives of neurology》1988,45(10):1126-1128
Four of five patients with brain metastases from melanoma had increased lofetamine I 123 uptake in the region of the tumor deposits. A comparison group of five patients with melanoma with no clinical or radiologic evidence of brain involvement and 46 of 47 patients without malignant melanoma but with known brain tumors of other histologic types had normal or decreased iofetamine I 123 brain uptake in the region of the tumor. An exception was one patient whose metastatic small cell lung cancer to the brain showed focally increased uptake. These findings suggest that certain brain tumors such as melanoma are capable of selectively binding iofetamine I 123 because of specific chemical properties of the radiopharmaceutical. Increased uptake of iofetamine I 123 in brain lesions in a patient at risk for metastatic melanoma may be a useful aid to differential diagnosis. 相似文献
998.
This paper presents results from psychophysical experiments on human binocular rivalry in central and peripheral vision. Results show that the incidence of periods of exclusive visibility of a given eye's rival target increased with decreasing target size, and for a given sized target exclusive visibility increased with retinal eccentricity. Control measures confirmed that these results were not attributable solely to reduced peripheral acuity, to Troxler's effect, or to spatial frequency. We computed the minimum-sized stimulus that would lead to a criterion level of exclusive visibility of one or the other eye; this we term the spatial zone of binocular rivalry. The change in estimated size of spatial zones of rivalry with eccentricity compares favorably with estimates of human cortical magnification. We propose a model that assumes concentrically organized zones of rivalry. These zones do not function independently, but instead exhibit a high degree of mutual excitatory cooperativity. The model has multiple solutions for the foveal zone size, but the best fits predict a diameter of 5.3 or 7.3 min of visual angle; these values dovetail nicely with our empirical estimates of the foveal zone size. 相似文献
999.
Comparison of the allergenicity and antigenicity of Polistes venom and other vespid venoms 总被引:2,自引:0,他引:2
R E Reisman J I Wypych U R Mueller J A Grant 《The Journal of allergy and clinical immunology》1982,70(4):281-287
The crossantigenicity of Polistes venom with other vespid venoms was examined with rabbit and human antisera. Venom preparations from various Polistes species were obtained by electrical stimulation of individual insects and venom sac dissection. Rabbit antibodies were raised to the venom (P. apachus) and venom sac extract (P. exclamans). Human antisera were obtained from patients allergic to Polistes and other vespid venoms. The venom appeared to be more potent than the venom sac preparations in reactions with rabbit IgG and human IgE antibodies. Among the Polistes species, P. exclamans, P. instablis, and P. apachus venoms showed several lines of precipitation with rabbit antisera, and P. annularis and P. fuscatus venoms only one line, suggesting quantitative or qualitative antigenic differences. In RAST analysis, most sera reacted equally to all Polistes species but occasional exceptions were noted, again suggesting differences in venom allergens. P. exclamans-coupled discs gave the most consistent results. In gel diffusion experiments, there was no crossreactivity between Polistes and yellow jacket venoms and only limited crossreactivity between Polistes and hornet venoms. Patients sensitive to Polistes venom showed varying degrees of reactivity to yellow jacket and hornet venoms in RAST analysis. Patients sensitive to other vespid venoms also showed varying degrees os sensitivity to Polistes venom. Polistes venom appears to contain a genus-unique antigen (allergen). In addition, there appear to be some crossreacting antigens in Polistes and other vespid venoms but to a much lesser degree than found previously in the analysis of the relationship of yellow jacket and hornet venoms. 相似文献
1000.
Donald L. Kaminski Max Jellinek Edgar J. Mueller 《The Journal of surgical research》1980,28(2):97-102
To evaluate the hypothesis that hepatic lipid accumulation following small intestinal bypass may be related to bacterial overgrowth in the defunctionalized small bowel, hepatic lipid metabolism was evaluated in rats with small intestinal bypass treated and not treated with antibiotics. Small bowel bypass in nutritionally obese rats decreased body weight and food intake when compared to sham-operated controls. Antibiotic-treated rats ate less than did the rats not receiving antibiotics. Small intestinal bypass did not increase hepatic lipid accumulation in no-antibiotic treated rats. The small intestinal bypass rats receiving antibiotics had less total hepatic lipid and less hepatic triglyceride than did sham-operated controls and less hepatic lipid than did the rats not receiving antibiotics. Decreasing the bacterial population of the defunctionalized small bowel is associated with changes in hepatic lipid metabolism in rats with small bowel bypass. These changes may be produced by alterations in nutrient intake or by elimination of a “toxic” substance produced by small bowel bacterial overgrowth. 相似文献