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991.
Swartz JD; Mandell DM; Faerber EN; Popky GL; Ardito JM; Steinberg SB; Rojer CL 《Radiology》1985,157(2):395-398
Ossification of the membranous labyrinth (labyrinthitis ossificans) develops as the final result of many inflammatory processes, for example, meningitis, blood-borne septic emboli, middle ear infection, and cholesteatoma. Labyrinthine ossification may also occur as a result of previous labyrinthectomy or secondary to trauma. Seven cases of labyrinthine ossification accompanied by severe vertigo and total hearing loss in the affected ear are discussed. The computed tomographic appearance of varying degrees of ossification, the clinical and surgical circumstances from which this disorder may develop, and the various approaches to labyrinthectomy are described. 相似文献
992.
993.
JH Drew K Marriage VV Bayle E Bajraszewski JM McNammara 《Archives of disease in childhood》1976,51(6):454-458
Use of phototherapy for hyperbilirubinaemia in 300 consecutively treated infants has shown that minor complications are common. With a knowledge of these complications and measures taken to minimize their effects, phototherapy appears to be safe in the short term. The long-term follow-up study showed that growth, and in particular head circumference, was not affected. There was, however, a higher incidence of squints and abnormal developmental performance in those infants treated with phototherapy. This may not have been due to phototherapy usage per se. However, because of these findings, it is suggested that phototherapy should not be used indiscriminately for hyperbilirubinaemia until the results of further long-term studies are available. 相似文献
994.
995.
The common acute lymphoblastic leukemia antigen (CALLA) is a 100-kd surface glycoprotein that is present on normal and malignant lymphoid cells. It is a useful marker for distinguishing between clinically important types of acute leukemia. Anti-CALLA monoclonal antibodies (MoAb) also react with mature myeloid cells (granulocytes), where they identify an antigen having a similar molecular weight (mol wt). We now report that the antigens detected by anti-CALLA MoAb on human lymphoid and myeloid cells differ in their behavior and chemistry. Surface- labeling studies indicate that the antigen on lymphoid cells has a mol wt of approximately 100 kd v 110 kd for that on granulocytes. When cells are metabolically labeled with 35S-methionine, differences in the mol wt of these antigens are again observed. Unlike the lymphoid antigen, expression of that on purified granulocytes is not modulated by incubation with specific antibody. Sodium dodecyl sulfate- polyacrylamide gel electrophoresis analysis of proteolytic digests of the two antigens fails to clarify their chemical relationship. Thus the antigens detected on these two cell types may share an epitope(s) but be chemically distinct, or CALLA may exist in distinct forms and behave differently on lymphoid cells and granulocytes. 相似文献
996.
997.
CT findings in Swyer-James syndrome 总被引:4,自引:0,他引:4
Swyer-James syndrome (SJS) is usually diagnosed with plain chest radiographs obtained during inspiration/expiration. The authors studied patients with CT to assess its value in the evaluation of this syndrome. In patients with SJS, CT was useful in the determination of bronchial patency (all nine patients), lung parenchymal changes (subpleural infiltrates in six patients, atelectasis in two, and cavities in two), and the extent and degree of bronchiectasis (all nine patients). If CT is used for the evaluation of bronchiectasis, knowledge of the main findings associated with SJS (hyperlucent lung without anteroposterior gradient attenuation [n = 8], small lung [n = 6], and diminished central and peripheral pulmonary arteries [n = 9]) should facilitate the diagnosis of associated SJS. Expiration CT would support the diagnosis with demonstration of air trapping. 相似文献
998.
Improved control of image optical density with low-dose digital and conventional radiography in bedside imaging 总被引:1,自引:0,他引:1
Schaefer CM; Greene RE; Oestmann JW; Kamalsky JM; Hall DA; Llewellyn HJ; Robertson CL; Rhea JT; Rosenthal H; Rubens JR 《Radiology》1989,173(3):713-716
The technical and diagnostic performance of simultaneously acquired low-dose (44% of standard dose) storage-phosphor digital radiographs (system resolution = 0.2 mm, 10 bits) were compared with those of standard-dose conventional bedside radiographs of the chest in 32 patients. The mean optical density (OD) of the lungs (800 measurements) was closer to the ideal density with digital radiography (1.45 OD +/- 0.20 [standard deviation] vs 1.75 OD +/- 0.53) and was less often outside the usable range (2.5% vs 42.5%). Receiver operating characteristic analysis for detection of simulated nodules and monitoring devices (nine readers, 4,608 observations) showed that digital radiography was superior to conventional radiography (P less than .05) for four of the nine readers and equivalent to conventional radiography for five readers. The authors concluded that digital radiography produces more consistent and ideal image density and performs at least as well as conventional radiography under phantom test conditions. 相似文献
999.
1000.
应用导数光谱法考察苯呋洛尔溶液体外经皮渗透性 总被引:1,自引:0,他引:1
本文应用二阶导数紫外分光光度法考察了苯呋洛尔溶液体外经皮渗透性。考察了促进剂月桂氮(?)酮-丙二醉及PEG-400溶剂对其渗透性的影响。应用二阶导数紫外分光光度法消除了兔皮溶出物对一般紫外测定方法的干扰。结果表明:苯呋洛尔溶液具有体外经皮渗透性;月桂氮(?)酮-丙二醇系统及PEG-400均能增强苯呋洛尔溶液的体外经皮渗透性。 相似文献