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991.
Impaired bacterial clearance and trapping in obstructive jaundice.   总被引:3,自引:0,他引:3       下载免费PDF全文
Sepsis is a major cause of mortality in patients with common bile duct obstruction. To define possible contributing factors to this phenomenon, this study evaluates the effect of biliary obstruction on the intravascular clearance and organ trapping of viable Escherichia coli using a rat model. Adult male Sprague-Dawley rats were placed in three groups: Group I controls had sham operation, Group II had division and ligation of common bile duct (CDL), and Group III underwent splenectomy. At 21 days following operation 10(9) radiolabeled E. coli were injected intravenously. At varying intervals after infusion, blood samples were obtained for clearance study. At 10 minutes, bacterial distribution in the liver, spleen, kidneys, and lungs was determined (expressed as the mean percentage of injected viable E. coli). Intravascular clearance was similar in all groups. There was a significant decrease in the trapping of bacteria by the liver of CDL rats 14.5% +/- 4.95 (vs. control = 70.0% +/- 13.3) (p less than 0.005). A significant increase of bacterial trapping by the lung was observed in the CDL animals: 63.1% +/- 7.06 (vs. controls 1.4% +/- 0.82) (p less than 0.005). There was no significant change in bacterial localization in splenectomized rats. These data suggest that biliary obstruction decreases hepatic phagocytosis and increases pulmonary localization of viable E. coli. As the Kupffer cells of the liver are usually effective in removal of blood borne bacteria, this phagocytic dysfunction may contribute to the increased susceptibility to infection noted in instances of biliary obstruction.  相似文献   
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This paper presents early experience with a primate model for the noninvasive study of the interaction of circulating platelets with healing arterial prostheses. These experiments demonstrate that baboon platelets can be isolated and labeled with 111Indium with high efficiency using a sterile technique. Platelets subjected to this process have a linear life span similar to that of 51Chromium-labeled baboon platelets. The high energy gamma emission of 111Indium oxine allows for external scanning using a standard gamma camera. The small quantity of 111Indium-labeled platelets in the region of the graft can be discriminated from the surrounding blood vessel and quantitated by gamma camera imaging and computer analysis. There was a significant increase in the platelet deposition on prosthetic surfaces observed 5--48 hours after graft implantation and injection of 111Indium-labeled autologous platelets.  相似文献   
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A total of 464 pathologically staged IA through IIIB Hodgkin's disease patients were evaluated for the risk of developing acute nonlymphocytic leukemia, non-Hodgkin's lymphoma, or a fatal infection after treatment with radiation therapy (RT) alone, initial combined radiation therapy and chemotherapy (CMT), or RT with MOPP administered at relapse. Patients received a standard six cycles of MOPP, and additional maintenance chemotherapy was not administered. Patients receiving total nodal irradiation (TNI) and MOPP chemotherapy have an 11.9% actuarial risk of developing a fatal complication at ten years, as compared to a 0.8% risk for lesser field irradiation and MOPP (P = .005). The risk with RT alone is 0.6%. Patients 40 years of age or older have a greater risk for complications. These data report a low risk for fatal complication with CMT when less than TNI is administered and when maintenance chemotherapy is not used.  相似文献   
997.
This is a retrospective analysis of 120 patients with pathologically stage IIIA and IIIB Hodgkin's disease treated from April 1969 to December 1982. The median follow-up was 108 months. Treatment consisted of radiation therapy (RT) alone in 54 patients and combined radiation therapy and MOPP (nitrogen mustard, vincristine, procarbazine, prednisone) chemotherapy (CMT) in 66 patients. Stage III patients treated with CMT have an improved actuarial 12-year survival as compared with patients treated with RT alone with MOPP reserved for relapse (80% v 64%; P = .026). The 12-year actuarial freedom from first relapse by treatment for stage III patients is 83% and 40%, respectively (P less than .0001). Improved survivals following combined modality therapy are seen for the following subgroups of stage III patients: stage III2, 66% (CMT) v 44% (total nodal irradiation; TNI), P = .04; stage III1, 97% (CMT) v 73% (TNI), P = .05; stage III mixed cellularity or lymphocyte depletion histology, 94% (CMT) v 65% (TNI), P = .007; and stage III extensive splenic involvement, 77% (CMT) v 58% (TNI), P = .02. These survival differences are not seen in patients with nodular sclerosis or lymphocyte predominance histology or in patients with minimal splenic involvement. These data indicate that the initial use of CMT in stage III Hodgkin's disease results in an improved survival as compared with initial treatment with RT with MOPP reserved for relapse. Patients with limited Stage IIIA disease may still be candidates for radiation therapy alone.  相似文献   
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