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71.
72.
5-羟色胺对气道平滑肌细胞增生的影响及c-fos的表达 总被引:7,自引:0,他引:7
5-羟色胺对气道平滑肌细胞增生的影响及c-fos的表达刘振千梁凤珍马军红戚好文为了探讨哮喘气道平滑肌层增厚的机制,考察哮喘的炎性介质5-羟色胺(5-HT)对兔气道平滑肌细胞(ASMC)增生的影响及原癌基因c-fos的表达。新西兰大白兔,抗α-肌动蛋白... 相似文献
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Deposition of autofluorescent eosinophil granules in pathologic bone marrow biopsies 总被引:2,自引:0,他引:2
Eosinophil granules are intensely autofluorescent when excited by green light. To determine if eosinophils degranulate in the bone marrows of patients with a variety of diseases, we used green light epifluorescence microscopy to examine deparaffinized and dezenkerized sections of 49 bone marrow core biopsies. In 14 of the biopsies, there was striking extracellular deposition of intensely autofluorescent eosinophil granules in addition to numerous intact eosinophils. Among the 14 specimens with extracellular autofluorescence were seven cases of leukemia, four cases of non-Hodgkin's lymphoma, two cases of myelofibrosis, and one case of pancytopenia with eosinophilia. In the remaining 35 specimens, only intact eosinophils were identifiable. There was no extracellular autofluorescence in three normal marrows, four marrows from AIDS patients, or three biopsies from patients with idiopathic thrombocytopenic purpura (ITP). We conclude that green light epifluorescence microscopy identifies extracellular deposits of eosinophil granules in bone marrow biopsies of some neoplastic disorders and in diseases associated with reticulin fibrosis. 相似文献
76.
A Chaikhouni F A Crawford P J Kochel L S Olanoff P V Halushka 《The Journal of thoracic and cardiovascular surgery》1986,92(1):88-91
The patency rate of internal mammary artery grafts is reported to be better than that of saphenous vein grafts in myocardial revascularization operations. To identify a possible biochemical explanation for this phenomenon, we studied the production of prostacyclin by the internal mammary artery and saphenous vein in 11 patients. Segments of internal mammary artery and saphenous vein from each patient were incubated in Krebs-Henseleit buffer at 37 degrees C. After 15 minutes, the basal production of 6-keto-prostaglandin F1 alpha (prostacyclin metabolite) by the internal mammary artery was 152 +/- 39 pg/mg wet weight (mean +/- standard error of the mean), whereas the saphenous vein produced only 68 +/- 17 pg/mg (p less than 0.001). After 30 minutes, the internal mammary artery produced 179 +/- 42 pg/mg, whereas the saphenous vein produced 75 +/- 18 pg/mg (p less than 0.001). After the basal incubation period, the vessels were incubated with arachidonic acid (prostaglandin substrate) for 15 minutes. The internal mammary artery produced 49.4 +/- 9.9 pg/mg, whereas the saphenous vein produced only 22.6 +/- 9.8 pg/mg (p less than 0.01). These observations suggest that the capacity of the internal mammary artery to produce prostacyclin in both a basal and a stimulated state is greater than that of the saphenous vein. Since prostacyclin is a potent vasodilator and inhibitor of platelet function, these results provide a possible biochemical explanation for the clinically observed better patency rate of internal mammary artery grafts. 相似文献
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Primary biliary carcinoma: CT evaluation 总被引:19,自引:0,他引:19
79.
Widrich WC; Beckman CF; Robbins AH; Scholz FJ; Srinivasan MK; Hayes EJ; Kellum CD; Newman T 《Radiology》1983,148(1):61-64
Iopamidol was compared with Renografin-60 (meglumine diatrizoate, Squibb) in a controlled, randomized double-blind study of 40 patients undergoing peripheral arteriography for arteriosclerotic occlusive disease to determine which agent caused less discomfort. Each patient was evaluated for objective signs of discomfort and subjective feelings of pain and heat. Monitoring was achieved by multiple physical examinations, chemical tests, electrocardiograms, and intra-arterial pressure recordings. It is concluded that iopamidol is safe and causes significantly less patient discomfort than Renografin-60. 相似文献
80.
A W Cuthbert P V Halushka H S Margolius J A Spayne 《British journal of pharmacology》1984,82(3):597-607
The output of immunoreactive (i) 6 keto prostaglandin F1 alpha (i6ketoPGF1 alpha), iPGE2 and ithromboxane B2 (iTXB2) from isolated colonic epithelium of the rat into the apical and basolateral bathing solution has been measured. In some instances tissues were also voltage clamped at 0 mV to measure short circuit current (SCC). Kallidin (lysylbradykinin) stimulated the output of all three eicosanoids, specifically from the basolateral face of the tissue. The output was similar whether or not the tissues were short circuited. Both the SCC response and eicosanoid output were dependent upon the concentration of kallidin, but not in a strictly proportional manner, there being relatively more eicosanoid output at submaximal kinin concentrations. Indomethacin, 5 microM, abolished the eicosanoid output, in response to kinin, while some part of the SCC response remained. Calcium removal from the basolateral bathing fluid severely attenuated the SCC response, reduced the output of i6ketoPGF1 alpha to half, but left the output of iPGE2 unchanged. In the presence or absence of calcium it is probable that sufficient PGE material is released to cause part of the SCC changes seen with kinin. Kinin and PGE1 increased the cyclic AMP content of intact epithelia, provided a phosphodiesterase inhibitor was added at the same time. It is proposed that kinin causes an increase in calcium influx at the basolateral pole of the tissue. This calcium is necessary for the production of some eicosanoids and the subsequent generation of cyclic AMP, which then increases apical chloride permeability. In addition, calcium may facilitate entry of chloride through the basolateral face of the cells by activating a cotransport mechanism. 相似文献