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221.
Forty patients with bladder carcinoma were examined preoperatively by means of magnetic resonance (MR) imaging. In all patients, total cystectomy with enterocystoplasty and pelvic node dissection was performed. The surgical and pathologic findings were correlated with the MR findings. Extension through the deep muscle of the bladder wall was present in 20 of the 40 patients and was diagnosed with a sensitivity of 95% and a specificity of 95%. Extension to perivesical fat was present in 18 of 40 patients and was diagnosed with a sensitivity of 66% and a specificity of 100%. Invasion of the adjacent organs was present in nine of 40 patients and was diagnosed with a sensitivity of 44% and a specificity of 96%. On the basis of the MR findings, the tumor was correctly staged, according to the TNM classification, in 24 of 40 (60%) patients, tumor extension was overestimated in three of 40 (7.5%) patients, and tumor extension was underestimated in 13 of 40 (32.5%) patients. MR imaging has been shown to be accurate in identification of macroscopic lymph node involvement and deep muscle involvement. It appears to be at least as useful as computed tomography (CT) in the evaluation of perivesical fat involvement and to be superior to CT in the detection of invasion of adjacent organs. One limitation of MR imaging is in the evaluation of tumor extension into the periurethral glands. 相似文献
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223.
To determine if interleukin-6 (IL-6) administration influences platelet function, platelet activation was analyzed sequentially in IL-6-treated (80 micrograms/kg/d) and control dogs. Platelet activation was determined in whole blood by flow cytometry by quantitating the binding of a monoclonal antibody to platelet surface P-selectin after stimulation with graded doses of thrombin. Administration of IL-6 resulted in a twofold decrease in the thrombin concentration required for induction of half-maximal P-selectin expression (ED50) compared with control animals. The ED50 returned to normal after cessation of IL- 6 administration. As measured by P-selectin expression, enhanced responsiveness to the strong agonist platelet activating factor (PAF) was also observed in the IL-6-treated dogs. IL-6 had no effect on the susceptibility of platelets to thrombin activation when incubated with anticoagulated dog blood. The data show that, in addition to augmenting the platelet count in normal dogs, IL-6 enhances the sensitivity of platelets to activation in response to thrombin and PAF. 相似文献
224.
Suprasellar germinoma: radiation therapy 总被引:3,自引:0,他引:3
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226.
Mantravadi RV; Gates JO; Crawford JN; Bajpai D; Trenkner JD; Jordan LN 《Radiology》1989,172(3):851-855
Between 1976 and 1983, 267 patients with non-oat cell carcinoma of the lung were treated with radiation therapy alone. One hundred thirty-four patients had squamous cell carcinoma; 69, large cell carcinoma; and 64, adenocarcinoma. Stage III carcinoma was diagnosed in 87% of the patients. Total radiation dose was less than 45 Gy in 69 patients (low dose group), 45-55 Gy in 161 (middle dose group), and 55-65 Gy in 37 (high dose group); dosage was 180-200 cGy daily, 5 days per week. Minimum follow-up was 3 years (median, 6 years). Tumor control within the radiation fields was achieved in 12%, 43%, and 78% of the low, middle, and high dose groups, respectively. A complete response rate of 13%, 23%, and 35% and an overall response of 43%, 71%, and 86% were seen in the low, middle, and high dose groups, respectively. The 5-year recurrence-free survival rate for all patients was 7% and was dependent on radiation dose and tumor response. This study indicates that tumor control and complete response rates are improved with a radiation dose of 55-65 Gy and that complete responders have improved survival. 相似文献
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228.
Anteroposterior radiographs of the fully flexed and slightly externally rotated elbow were obtained in 122 cases of cubital tunnel syndrome (CUTS) and in 33 normal elbows. Medial trochlear lip osteophytes were not found in the studies of normal elbows but were noted in 20% of ulnar nerve entrapment cases. Medial incongruity between the trochlea and the olecranon greater than or equal to 5 mm was found in 29% of CUTS cases and in 6% of normal elbows. The presence of posttraumatic elbow-joint deformities seen on radiographs correlated significantly with the degree of clinical involvement. Depth and area measurements of ulnar nerve compression, performed using a line-art representation of the radiographs, showed a significant (P less than .0001) correlation between decrease in the area of the cubital tunnel and ulnar innervated muscle atrophy. These findings confirm the importance in this syndrome of both osteoarthritis and incongruity of the medial structures of the elbow joint. 相似文献
229.
Function of integrin in duodenal mucosal uptake of iron 总被引:4,自引:0,他引:4
A mechanism for the absorption of inorganic iron in the small intestine is described in which integrins appear to play an important role in the passage of iron across microvillous membranes. Biochemical isolates from microvillous preparations of duodenum from rats dosed with radioiron showed radioactivity concentrated in integrins. The presence of integrins on mucosal surfaces of duodenal cells was confirmed by immunofluorescent microscopy using anti-integrin monoclonal antibodies. Immunoprecipitation methods were used to show that microvillous radioiron was precipitated with anti-integrin antibodies and that mobilferrin, a 56-Kd cytosol iron-binding protein, coprecipitated with integrins. We postulate from these data that the mucosal uptake of iron from the gut lumen is mediated via an integrin-mobilferrin pathway. 相似文献
230.
CT Cowell PW Lu SA Lloyd-Jones JN Briody JR Allen IRJ Humphries E Reed J Knight R Howman-Giles K Gaskin 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(S411):12-16
The use of areal bone mineral density (aBMD) in paediatric populations has aroused some concern, as it fails to take the age-related increase in bone thickness into account. We have developed a measure of true bone density, volumetric bone mineral density (vBMD), which is independent of age and height. In order to examine the relationship between growth parameters, aBMD and vBMD, we studied patients with phenylketonuria (PKU, n = 40), chronic renal failure (CRF, n = 27) and chronic asthma (n = 19). aBMD of the femoral neck and the mid-femoral shaft was measured using dual energy X-ray absorptiometry (DXA), vBMD was calculated on the basis of values of bone mineral content and bone dimension provided by DXA, with the assumption that both sites are cylinders. aBMD and vBMD were then compared with the normal reference, expressed as a standard deviation score (SDS). aBMD and vBMD were normal in the femoral neck region of the PKU group, but aBMD, either standardized for age or for height, was low in the femoral shaft region ( p < 0.01). In the CRF group, profound growth retardation was seen (mean height SDS, −3.2) and aBMD and vBMD were both low in the femoral shaft region but not in the femoral neck. In the asthma group, aBMD for age was low at both sites, but vBMD did not differ from that seen in normal individuals. We conclude that the true vBMD provides a different interpretation of bone density compared with aBMD and requires further evaluation in paediatrics because of its age and height independence. 相似文献