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Preoperative cardiovascular hemodynamics and percutaneous liver biopsies were used to evaluate the pathophysiologic factors determining the operative prognosis of patients with cirrhotic liver disease and bleeding esophageal varices. These studies confirm the observations of Siegel that the greater the magnitude of the peripheral abnormalities in vascular tone and oxygen consumption the better must be the capability of the ventricular function, if the cirrhotic is to survive emergency or urgent portal decompressive surgery. These studies also show that the cardiovascular hemodynamics are directly correllated with the nature and degree of the abnormalities in the liver biopsy, and that pathologic and physiologic features of this disease which impact on surgical prognosis can be expressed through the easily obtained Survival Index. Bleeding cirrhotic patients with poor quality hemodynamics and poor histologic characteristics should be treated non operatively, since the operative mortality appears greater than that produced by a strategy of medical supportive therapy and delayed surgery if stabilization occurs.  相似文献   
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Differential CT diagnosis of extruded nucleus pulposus   总被引:1,自引:0,他引:1  
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PURPOSE: To investigate use of the macromolecular contrast agent feruglose for differentiating and grading of human benign and malignant breast tumors on the basis of their microvascular characteristics. MATERIALS AND METHODS: Sixty-three women with 63 primary breast lesions were examined with dynamic T1-weighted gradient-echo magnetic resonance (MR) imaging after intravenous injection of feruglose. A two-compartment unidirectional kinetic model applied to the dynamic data yielded estimates of the endothelial transfer coefficient, KPS, and the fractional plasma volume of the tumors. These MR imaging-derived parameters were correlated with the histologic tumor grade and quantified according to the Scarff-Bloom-Richardson (SBR) score by means of Pearson product moment correlation analyses. Differences between malignant and nonmalignant breast lesions with respect to KPS for feruglose were evaluated by means of the chi2 test and by calculating the sensitivity, specificity, and positive and negative predictive values. RESULTS: Histologic analysis revealed 26 benign and 37 malignant tumors. A moderate yet statistically significant correlation between KPS and SBR score was found (R = 0.496, P <.001). No significant correlation was observed between fractional plasma volume and SBR score (R = 0.085, P =.507). The KPS values were zero for 19 (73%) of the 26 benign tumors and were greater than zero for 27 (73%) of the 37 carcinomas. This distribution was significantly different (chi2 = 13.035, P =.001). With the criterion KPS > 0 in carcinomas, sensitivity was 0.73, specificity was 0.73, and the positive predictive value was 0.79. CONCLUSION: Quantitative measures of tumor microvascular permeability can be used for breast tumor characterization. The probability of breast tumor microvascular hyperpermeability to be associated with malignancy is 79%.  相似文献   
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At birth, premature infants of 25-29 weeks gestation, at high risk for development of neonatal respiratory distress syndrome (RDS), were given a single dose (90 mg) of calf lung surfactant extract (CLSE) by intratracheal instillation. The frequency and severity of RDS were assessed with use of a simple radiographic scoring system in which pulmonary parenchymal densities and the prominence of the air-bronchogram effect were used as indicators of widespread atelectasis. Radiographs were obtained in surfactant-treated and control infants within the first 90 minutes of life as part of an initial evaluation of their pulmonary status. Subsequent examinations were performed at less than 24 hours and less than 48 hours of age. Radiographic assessment of lung disease compared consistently with coordinated data on oxygen and mean airway pressure requirements of the infants. Both indicated a significantly decreased frequency and severity of RDS in the infants treated with surfactant. The results provide supporting evidence of the effectiveness of exogenous lung surfactant replacement in mitigating RDS in very premature infants.  相似文献   
57.
Differential diagnosis between pancreatic cancer and chronic pancreatitis is still difficult to establish. In 63 patients with suspected pancreatic neoplasm we performed: serum CA 19-9 assessment, abdominal ultrasound. CT scan and CT-guided pancreatic percutaneous fine-needle biopsy. The conclusive diagnosis was pancreatic cancer in 40 patients and chronic pancreatitis in 23 patients. With regard to the differential diagnosis, sensitivity and specificity were respectively 80% and 78% for serum CA 19-9, 75% and 65% for abdominal US. 85% and 70% for CT scan. 00% and 87% for percutaneous fine-needle biopsy. We conclude that CT-guided percutaneous fine-needle biopsy is the most reliable method for differential diagnosis between pancreatic cancer and chronic pancreatitis.  相似文献   
58.
Color Doppler flow imaging or compression ultrasound (US) was used to prospectively determine frequency of thrombosis at 54 venous insertion sites (47 in common femoral veins, seven in right internal jugular veins) after percutaneous placement of Greenfield filters for interruption of the inferior vena cava. Fifty-one filters were successfully placed in 51 patients with a dilator set or a balloon angioplasty catheter. Nine focal thrombi were detected in the common femoral vein (19%) and one in the right internal jugular vein (14%). Use of dilators induced eight thrombi (24%), compared with two (10%) from balloon catheters. The left common femoral vein had a high frequency of thrombosis, regardless of dilation technique (five of nine). Of nine patients with acute common femoral vein thrombosis, four became symptomatic within 10 days after the procedure. Patients may remain asymptomatic or have delayed symptoms; thus, US is valuable for determining patients at risk of thrombosis of the common femoral vein.  相似文献   
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