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941.
942.
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
943.
944.
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
945.
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
946.
947.
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
948.
949.
Magnetic resonance (MR) imaging was performed on 15 healthy subjects to define the appearance of the iliopsoas muscle and on 15 patients with iliopsoas disease. Seven patients had tumorous involvement of the muscles, five had inflammatory disease, one had retroperitoneal hemorrhage, one had iliopsoas bursitis, and one had bilateral hypertrophy. MR imaging permitted delineation of the muscles and depiction of the disease condition. Transverse MR images alone almost always provided the necessary data to determine the origin and extent of disease. Sagittal images were occasionally useful in defining the extension of disease into the spine. T1-weighted images provided optimal contrast between the muscles and adjacent tissues, while T2-weighted images were more useful for depicting disease within the muscles themselves. 相似文献
950.
To ascertain the optimal treatment for carcinoma of the piriform sinus, the authors determined survival rates and local and regional tumor growth for two groups of patients: those treated by radiation therapy alone (n = 209) and those treated by radiation therapy combined with surgery (n = 154). The two groups were similar with respect to the characteristics of primary tumor stage and degree of nodal involvement. The overall 3-year and 5-year actuarial survival rates were 19.2% and 15.5%, respectively. For 5-year actuarial survival, there was no significant difference between patients with T1 and T2 tumors, but there was a significant difference between patients with T1 + T2 tumors versus those with T3 tumor. There was no significant difference in 3- and 5-year survival between patients with N0 and N1 nodal involvement and those with N1 and N2 involvement, but there was a significant difference between patients with N0 versus those with N3 involvement. The 5-year actuarial survival rate is significantly better for patients who underwent surgery followed by radiation therapy than for those who received only radiation therapy. However, for patients with early-stage (T1 and T2) tumors, radiation therapy alone controls local tumor growth as well as the combination of surgery and radiation therapy does. For each treatment group, the causes of death and patterns of failure were studied and compared with investigations to date. 相似文献