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51.
Improvement of oxygen metabolic reserve after extracranial-intracranial bypass surgery in patients with severe haemodynamic insufficiency 总被引:8,自引:0,他引:8
Summary The effectiveness of extracranial-intracranial arterial bypass (EC-IC bypass) surgery on impaired haemodynamic status was studied in 12 patients with reduced regional cerebral perfusion pressure (rCPP) and elevated regional oxygen extraction fraction (rOEF) in the area distal to the symptomatic arterial lesion. Postoperative positron emission tomography (PET) study demonstrated a statistically significant decrease of rOEF in the operated hemispheres with disappearance of the pre-operative interhemispheric rOEF difference. Regional cerebral blood flow (rCBF) and regional cerebral oxygen metabolism (rCMRO2) were also increased in the operated hemispheres with disappearance of the pre-operative interhemispheric differences. Regional CBF/regional cerebral blood volume (rCBV) ratios of the symptomatic hemispheres were increased after surgery, but were still lower than in the contralateral hemispheres. We conclude that EC-IC bypass surgery improves impaired cerebral oxygen metabolic reserve. 相似文献
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53.
BACKGROUND. Some specific chromosome abnormalities for the leukemias have been proven to be associated with the prognosis of acute nonlymphocytic leukemia (ANLL). However, most of these reports included patients treated with different protocols. Therefore, some bias has been involved in the evaluation of the prognostic factors in such reports. METHODS. The authors studied the morphologic, cytogenetic, and clinical features of 136 patients (86 males and 50 females) with de novo ANLL treated with the same protocol of intensive induction chemotherapy using multivariate analyses. RESULTS. Chromosome abnormalities were detected in 62.5% of the patients. The overall complete remission (CR) rate of disease was 85.5% in these patients. More than 90% of the patients with t(8;21) and pseudodiploid abnormalities achieved experienced CR. However, CR rates in the patients with abnormalities of chromosome 5 or 7 were 50%. With multivariate analyses by the type of karyotypic abnormality, CR duration and survival time of the patients with t(8;21) were longer than those of patients with normal karyotype and abnormalities of chromosome 5 or 7. Abnormalities of chromosome 5 or 7 and hyperdiploid were associated with poor prognosis. Older age and lower platelet counts also were factors contributing to shorter survival times. With the analysis with French-American-British (FAB) classification, only hypoplastic leukemia was a poor prognostic factor. CONCLUSIONS. These data suggest that cytogenetic analyses plays an important role in estimating the prognosis of patients treated with intensive induction chemotherapy. 相似文献
54.
BACKGROUND AND METHODS. A univariate and multivariate analysis for the correlation between histomorphologic factors and prognosis was made using data from 1116 patients with soft tissue sarcoma, including 1005 cases available with complete histologic and follow-up data. RESULTS. The overall 5-year survival rate was 43.6%. The univariate analysis using Kaplan-Meier survival curves showed that tumor differentiation, cellularity, nuclear atypia, cellular pleomorphism, mitotic activity, amount of fibrous stroma, extent of myxoid areas, extent of tumor necrosis, and histologic grading (determined by the estimated range of malignancy for each type of sarcoma using a reported guideline) were all significant prognostic factors in the overall soft tissue sarcoma group. By a multivariate analysis using a procedure based on the Weibull model to failure data, the histologic grading and extent of tumor necrosis were proved to be prognostically significant in the overall sarcoma group. However, after additional analysis on each histologic type of sarcoma, it was determined that both tumor necrosis and histologic grading were applicable in only two types: malignant fibrous histiocytoma and leiomyosarcoma. Liposarcoma, synovial sarcoma, and malignant schwannoma each also showed some determinable factor of prognostic significance. CONCLUSIONS. It was concluded that there seemed to be no single universal prognostic parameter that could be applied to each soft tissue sarcoma type. These results suggest that the predictive significance of the various histologic parameters should be based on each specific type of sarcoma. 相似文献
55.
Three cases of tubular adenoma of the gallbladder with squamoid spindle cell metaplasia are reported. Two of the three patients, who were middle-aged Japanese, had a solitary polyp in the gallbladder, and the other had three polyps. All the lesions were detected incidentally by ultrasonography. The polyps were pedunculated with a fine or frail stalk, and ranged from 0.5 to 3.9 cm in diameter. Histologically, they were tubular adenomas accompanied by scattered foci composed of a compact collection of short-spindle or oval cells with mild atypia. These cells did not retain intercellular bridges, and lacked intracellular keratinization. Immunohistochemically, the spindle cells stained positively for high-molecular-weight cytokeratin (EAB 903, a marker of squamous cell differentiation), whereas adenoma cells lining the tubules were negative for this antigen. Therefore, the spindle cell component is considered to represent squamoid metaplasia of adenoma cells. 相似文献
56.
Pharmacokinetic analysis of antibody localization in human colon cancer: Comparison with immunoscintigraphy 总被引:2,自引:0,他引:2
Atsushi Kubo Kayoko Nakamura Michiaki Katayama Shozo Hashimoto Tatsuo Teramoto Susumu Kodaira 《Annals of nuclear medicine》1992,6(1):21-27
The biodistribution and imaging characteristics of the 111In-labeled anti CEA monoclonal antibody ZCE-025 were studied in five patients with suspicion of colorectal carcinoma. Evaluation included antibody pharmacokinetics and assessment of antibody distribution in surgical specimen, making a comparison with whole-body imaging with a gamma camera. ZCE-025 localization in tumors was demonstrated by gamma-camera imaging in 4 of the 5 patients, corresponding to surgical findings. Persistent accumulation of 111In in the lymph nodes was observed in one patient, whereas surgical exploration of these lymph nodes showed no gross or microscopic evidence of metastases of colon carcinoma. Analysis of individual plasma by size exclusion HPLC showed two radioactivity peaks, labeled antibody and free DTPA. No transchelation of 111In to circulating transferrin was observed. The blood clearance was fitted to a two-compartment equation and its half-lives were found to be 10.8 +/- 8.7 h and 69.5 +/- 21.8 h for t1/2 alpha and t1/2 beta, respectively. Total urinary excretion averaged 0.3% of the injected dose/h with a small patient to patient variation. At 24 hrs postadministration the predominant radiolabeled species in urine was free DTPA. Thereafter, radioactivity in urine was partly present as a low molecular weight catabolic product. No apparent correlation between CEA content and uptake of 111In-ZCE-025 in tumors resected by surgery could be found. How 111In-labeled antibody is accumulated into tumors as well as into some nontumor tissues needs further study. 相似文献
57.
58.
59.
Prediction of postoperative respiratory failure in patients undergoing lung resection for lung cancer 总被引:2,自引:0,他引:2
K Nakahara K Ohno J Hashimoto S Miyoshi H Maeda A Matsumura T Mizuta A Akashi K Nakagawa Y Kawashima 《The Annals of thoracic surgery》1988,46(5):549-552
To evaluate the correlation between predicted postoperative lung function and postoperative respiratory morbidity, 156 patients with lung cancer who underwent resection were classified into four groups based on the degree of postoperative problems: Group 1--no problems (116 patients); Group 2--retention of sputum or atelectasis requiring bronchofiberscopy two or more times (17 patients); Group 3--tracheostomy or mechanical ventilation for more than 2 days or both (14 patients); and Group 4--postoperative death (9 patients). The mean ages of Groups 2, 3, and 4 were significantly (p less than 0.05) higher than the mean age of Group 1. The predicted postoperative lung function (F) was assessed by the formula F = [1-(b-n)/(42-n)] x f, where f is the preoperative vital capacity or forced expiratory volume in one second, b is the number of subsegments of the resected lung lobe, and n is the number of subsegments obstructed by the tumor, which was assessed by the findings on the chest tomogram, on the bronchogram, at bronchofiberscopy, or a combination of these. The total number of subsegments was assumed to be 42. The predicted postoperative % FEV1 was 65.1 +/- 19.3% in Group 1,55.3 +/- 10.6% in Group 2,37.6 +/- 12.1% in Group 3, and 42.3 +/- 18.4% in Group 4. It was significantly (p less than 0.05) different between all the groups except between Groups 3 and 4. All 10 patients with a predicted postoperative % FEV1 of less than 30% were in Groups 3 and 4. We conclude that special attention to postoperative management is needed for patients whose predicted postoperative %FEV1 is lower than 30%. 相似文献
60.
T Urakawa Y Nagahata Y Azumi Y Hashimoto A Itoh K Takeda I Sano Y Saitoh 《Scandinavian journal of gastroenterology》1988,23(6):705-711
We experimentally studied the influence of vagotomy on hepatic regeneration in rats after hepatectomy of cirrhotic livers. In animals that underwent hepatectomy plus vagotomy the reduction in gastric pH was suppressed, but gastric mucosal blood flow was less than that in control animals that received hepatectomy alone. The suppression of 3H-thymidine uptake percentage and thymidine kinase activity after hepatectomy was more marked in animals treated with hepatectomy plus vagotomy than in controls treated with hepatectomy alone. Hepatic DNA level tended to be lower in animals treated with hepatectomy plus vagotomy than in controls. In animals treated with hepatectomy plus vagotomy, the peak level of the mitotic index was lower and the hepatic regeneration rate was evidently suppressed. These results suggest that it is not appropriate to apply vagotomy, during hepatectomy of cirrhotic livers, for the prevention of postoperative stress ulcer because it causes a marked reduction in gastric mucosal blood flow and suppresses hepatic regeneration. 相似文献