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991.
McGahan  JP; Lindfors  KK 《Radiology》1988,167(3):669-671
Results of gallbladder bile aspiration and culture were correlated with presence or absence of acute cholecystitis in 36 patients to test the role of these procedures in hospitalized patients with sepsis. Diagnostic aspiration of the gallbladder was performed in 11 patients, and in the remaining patients a combination of percutaneous aspiration, percutaneous cholecystostomy, or cholecystectomy was used. Bile culture was not helpful in the prediction of acute cholecystitis, since results were not available for a minimum of 24-48 hours after aspiration. In addition, gram-stained smears and bile cultures suffered from low sensitivity (48% and 38%, respectively); consequently, a negative test does not allow the diagnosis of acute cholecystitis to be excluded. Bile aspiration of the gallbladder thus has a limited role in the diagnosis of this condition.  相似文献   
992.
Twenty percutaneous transluminal angioplasty (PTA) procedures and 13 percutaneous venous embolization (PVE) procedures were performed in 23 patients who either had or were at risk for the development of recurrent bleeding, hepatic encephalopathy, or both after surgical shunt placement for portal hypertension. PTA, performed in 12 patients with significant shunt stenoses, resulted in reduction or elimination of gradients in all patients; rebleeding has occurred in only one patient. Complications consisted of one fatal rupture of a mesocaval interposition vein graft and one balloon rupture requiring surgical removal. PVE, performed in 11 patients, resulted in measurable improvement in four of seven encephalopathic patients and temporary control in the two patients with intractable bleeding. Three patients underwent PVE prophylactically. PTA of graft strictures is a valuable treatment modality. Embolization may be helpful in selected cases of hepatic encephalopathy.  相似文献   
993.
994.
We analyzed the results of 607 small bowel biopsies performed over a seven-year period: 284 biopsies were obtained using a fiberendoscope and 323 biopsies using a Watson capsule. Three to six specimens were removed during endoscopy. The biopsy fragments obtained with the fiberendoscope were deeper than those obtained with the Watson capsule (p less than 0.0001) and were more often located in the duodenum (p less than 0.0001). The failure rate of the fiberendoscope biopsies (1%) was lower than for the Watson capsule biopsies (9%) (p less than 0.0001). Multiple biopsies increased the diagnostic value of fiberendoscopy which was 95% versus 85% for Watson capsule. The mean duration of the endoscopic procedure recorded in 30 children was 6.5 min for four to six samples, i.e. 1.5 min per biopsy specimen. Fiberendoscopy appears to be an efficient and safe method for performing small bowel biopsies in infants and children.  相似文献   
995.
996.
997.
Six hundred and twelve monoclonal Ig (MIg) were studied for their antibody activity against the following autoantigens: actin, tubulin, thyroglobulin, myosin, myoglobin, fetuin, albumin, transferrin, and double-stranded DNA (dsDNA). Of these 612 MIg, 36 (i.e., 5.75%) were shown to possess antibody activity. Thirty-two of these 36 (5.22% of the total) were mainly directed against actin. The four others were directed, respectively, against tubulin, myosin, thyroglobulin, and dsDNA. The interaction of the MIg with the respective antigen was demonstrated by immunoenzymatic methods with monospecific antisera and by blotting experiments. Furthermore, this interaction in the 12 cases studied was mediated by the dimeric fragment F(ab')2 of the MIg. The MIg with antitubulin, antithyroglobulin, and anti-dsDNA activities were exclusively inhibited by their homologous antigens. Those with antiactin activity were predominantly inhibited by actin and also by tubulin and thyroglobulin. The one binding to myosin was, for the most part, inhibited by myosin and also significantly by actin and tubulin. Retrospective clinical analysis was possible for 31/36 patients. Twenty- six of 31 had malignant lymphoplasmocytic disorders. The five others were followed for miscellaneous disorders without overt signs of multiple myeloma (MM) or Waldenstrom's macroglobulinemia (WM). The correlation between the antibody activity of the MIg and the clinical features is discussed. These results indicate that a high proportion of MIg possess antibody activity against actin (5.22%). This incidence contrasts sharply with the positive reactions found toward all the other antigens tested: only one each for dsDNA, tubulin, thyroglobulin, and myosin, and none against myoglobin, fetuin, albumin, and transferrin. The significance of these results and the relationship between MIg and natural antibodies are discussed.  相似文献   
998.
Lee  JK; Heiken  JP; Dixon  WT 《Radiology》1985,156(2):429-433
Fourteen patients with hepatic metastases underwent magnetic resonance (MR) imaging using both the conventional spin-echo (SE) technique and the opposed phase of the proton spectroscopic imaging method. The opposed image showed more lesions than the conventional SE image in five patients and provided better contrast between the liver parenchyma and metastases in two patients. Four of these seven patients had associated fatty infiltration of the liver. When compared with the computed tomography (CT) scan, the opposed image either showed more lesions or provided better contrast in six patients, four of whom had fatty infiltration. More significantly, the MR image showed several 1-cm lesions not shown by the CT scan in one patient. Our study discloses the possible explanations for the increased sensitivity of the opposed image in detecting hepatic metastases.  相似文献   
999.
To evaluate radiographic criteria recently proposed for determining causes of pulmonary edema, the authors studied 45 patients with severe pulmonary edema. Hydrostatic and increased permeability edemas were distinguished by means of the ratio of pulmonary edema fluid protein to plasma protein concentration and clinical and hemodynamic data. Chest radiographs were classified as showing hydrostatic, increased permeability, or mixed edema by three independent readers without knowledge of the clinical diagnosis. Overall, 87% of patients with hydrostatic edema but only 60% of patients with increased permeability edema were correctly identified. A patchy, peripheral distribution of edema was the single most discriminating criterion and was relatively specific for increased permeability edema, occurring in 13% of patients with hydrostatic and 50% with increased permeability edema (P less than .05). Some features considered more typical of hydrostatic edema were commonly found in patients with increased permeability, including a widened vascular pedicle (56%), pleural effusions (36%), peribronchial cuffs (72%), and septal lines (40%). The authors conclude that chest radiography is limited in the differentiation of type of pulmonary edema in severe cases.  相似文献   
1000.
With change in the imaging technique and magnetic field strength used in magnetic resonance imaging, wide variations in the delineation of pathologic features occur. Using imaging data from patients with known pathologic conditions, we evaluated the intensity images in spin-echo and inversion-recovery imaging at varying repetition times, echo times, and inversion times over broad ranges and changing magnetic field strengths. Differences in conspicuity and the apparent size of the lesions are important to consider in diagnosing and evaluating pathologic conditions, especially when different imagers and techniques are employed.  相似文献   
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