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Tidwell  T; Guzman  G; Vogler  WR 《Blood》1981,57(4):794-797
The action of an alkyl-lysophospholipid (ALP), ET180CH3, on clonogenicity, 3H-TdR uptake, and cell numbers was tested in two human leukemic cell lines, HL60 and K562, and short-term human leukemic bone marrow cultures. ALP eliminated clonogenicity in HL60 but not in K562 cultures; 3H-TdR uptake and cell numbers were depressed at low concentrations of ET180CH3 in HL60, but not K562 cultures. The action of the lysophospholipid analog on human leukemic bone marrow short-term cultures at low concentrations was similar to its action on HL60 cultures; clonogenicity and 3H-TdR uptake were depressed, but cell numbers were not significantly affected. The demonstration of differential action of ALP on two cell lines should significantly simplify the investigation of the mechanism of the reported differential action of ET180CH3 on normal and leukemic cell membranes.  相似文献   
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Computed tomography in dissection of the thoracic aorta   总被引:3,自引:0,他引:3  
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Surface shield: device to reduce personnel radiation exposure   总被引:2,自引:0,他引:2  
A simple device is described that can reduce personnel exposure from scatter radiation by up to 75%. The device consists of an oblong piece of shielding (0.75-mm lead equivalent) that is taped to the side of the patient during percutaneous renal stone removal and other interventional procedures. Contrary to other shields and barriers, this does not interfere with access to the patient. Scatter exposure data from phantom studies are presented and the rationale for surface shielding discussed.  相似文献   
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Pulmonary lymphangitic spread of carcinoma: appearance on CT scans   总被引:6,自引:0,他引:6  
Stein  MG; Mayo  J; Muller  N; Aberle  DR; Webb  WR; Gamsu  G 《Radiology》1987,162(2):371-375
Chest computed tomography (CT), including high-resolution CT with thin (1.5-mm) sections was used to evaluate proved (pathologically or clinically) lymphangitic spread (LS) of tumor in 12 patients. These appearances were compared with thin-section scans obtained in 11 healthy subjects. Thin-section CT demonstrated findings consistent with thickening of the normal lung interstitium. In all patients, thin sections showed an increase in the number of peripheral lines (1-2 cm in length) that were diffuse in generalized disease and localized in focal disease. Normal peripheral arcades were not increased in number, but the limbs forming the arcades were thickened in all patients. A diffuse increase in linear and curvilinear structures (reticular pattern) was seen toward the center of the lung. Polygonal structures 1-2 cm in diameter were seen in seven patients with LS but not in healthy subjects. Fissures were thickened in nine patients. Selected 1.5-mm-thick CT sections are recommended through abnormal areas (seen at CT or on chest radiographs) or if these are normal at three levels (midapex, hilus, and 3 cm above the diaphragm) when scanning patients with tumors known to cause LS.  相似文献   
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