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Radiologic diagnosis of oat cell cancer in a high-risk screened population   总被引:1,自引:0,他引:1  
A screening program of 10,040 cigarette-smoking men over 45 years of age was undertaken in an attempt to achieve earlier diagnosis, thereby increasing the cure rate, of oat cell lung cancer. Of the 155 men who were found to have lung cancer, 27 (17%) had confirmed oat cell cancer. Only one case was diagnosed at the first examination. The other 26 cases (called incidence cancer) were diagnosed by subsequent examinations. In 24 of the 26 patients, the tumor was not found until it was advanced (Stage III), and of these patients, only one is alive at 21 months follow-up. Two tumors were diagnosed as oat cell carcinoma at an early stage (Stage I), and both patients are alive with no evidence of disease at seven and 24 months. The screening program used in this study did not succeed in detecting oat cell cancer at an early stage.  相似文献   
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外源性AA引起兔动脉条收缩,呈剂量依赖性;EPA抑制AA收缩血管亦呈浓度依赖性;DHA对AA收缩血管作用无明显影响。破坏血管内皮后AA收缩血管作用大为减弱,EPA抑制AA收缩血管作用也几乎消失。吲哚美辛能阻断AA收缩兔主动脉条的作用。兔主动脉6-keto-PGF、TXB2及其比值随AA浓度升高而增加,低剂量EPA对前列腺素类代谢无明显影响,较大剂量时则降低上述指标。  相似文献   
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Abdominal radiography, excretory urography, retrograde pyelography, and computed tomography were performed in two patients who had undergone retrograde pyelography with thorium dioxide (Thorotrast) approximately 40 years ago. Both patients developed a transitional cell carcinoma due to suburothelial thorium deposition. Typical thorium densities were demonstrated at CT in the peripelvicalyceal area as well as in retroperitoneal lymph nodes. Elderly patients in whom radiographic examination reveals retained Thorotrast in the kidney should be followed up because of the high risk of renal carcinoma.  相似文献   
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Klatskin tumors of the bile ducts: sonographic appearance   总被引:4,自引:0,他引:4  
Meyer  DG; Weinstein  BJ 《Radiology》1983,148(3):803-804
The authors present 3 cases of surgically proved Klatskin tumor diagnosed by ultrasound alone. Sonographic features of these tumors include (a) dilatation of the intrahepatic biliary ducts but not the extrahepatic duct, (b) non-union of the right and left hepatic ducts, and (c) small, solid masses at the hepatic hilus. Local spread to the liver may also be seen. If the pancreas appears normal and no primary tumor can be found, Klatskin tumor can be diagnosed with a high degree of accuracy.  相似文献   
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BACKGROUND: Experimental studies in adults and in animals have reported that estimation of the intracardiac volumes by arterial thermodilution is a more reliable method of blood volume estimation than pressure measurement. The objective of this study has been to analyze the values of cardiac function and blood volume in an infant animal model using the arterial thermodilution technique. METHODS: A total of 202 measurements of cardiac output were performed by femoral arterial thermodilution in 38 Maryland piglets weighing between 8 and 16 kg, to determine the normal values of blood volume obtained by arterial thermodilution (PiCCO method) in an infant animal model. The following parameters were measured: blood volume [global end-diastolic volume index (GEDVI), total intrathoracic blood index (ITBI), extravascular lung water index (ELWI), systolic volume index (SVI)] and parameters of cardiac and vascular function [systolic volume index (SVI), cardiac function index (CFI), left ventricular contractility (Dp/dtmax), and systemic vascular resistance index) (SVRI)]. RESULTS: The cardiac index, 4.3 +/- 1.2 l x min(-1) x m(2), was within the normal range. The GEDVI, 198 +/- 48.6 ml x m(2), and ITBI, 574.1 +/- 113.4 ml x m(2), were lower than the normal values reported in adults, whereas the ELWI, 16.3 +/- 5.2 ml x kg(-1), was higher. CONCLUSIONS: Intrathoracic and intracardiac volume values obtained by arterial thermodilution are lower than those considered normal in the adult, whereas the extravascular lung water is higher. These values must be taken into account when the PiCCO method is used in small children.  相似文献   
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