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Delayed hypersensitivity (DH) was induced in the footpads of mice sensitized to methylated bovine serum albumin (MBSA). The magnitude of this DH response increased with increasing sensitizing concentration of MBSA. Levamisole administered 1 hr prior to MBSA challenge stimulated the DH response and this was optimal using subliminal sensitizing concentrations of antigen. A number of antirheumatic agents, immunomodulators mediator antagonists and antiallergies were subsequently examined using the subliminal sensitizing concentration of MBSA. The same drugs were also evaluated using a normal sensitizing procedure. These studies indicate that the sensitizing concentration of antigen is critical in establishing whether a drug will stimulate or suppress a DH response.  相似文献   
83.
Liver transplantation: MR angiography with surgical validation   总被引:6,自引:0,他引:6  
Thirty patients (mean age, 45 years) were evaluated with magnetic resonance (MR) angiography before liver transplantation to assess the accuracy of MR angiography. A series of breath-hold, two-dimensional images were acquired and subsequently processed to form three-dimensional projection angiograms. Graphic information on blood flow in the portal vein was acquired by using presaturation bolus tracking. Correlative duplex ultrasound (US) was performed in 28 patients, and surgical or autopsy correlation was available in all cases. MR angiography demonstrated patency of the portal vein in 26 (96%) of 27 patients, made possible the diagnosis of portal venous occlusion in three of three patients, depicted reversed portal flow in one patient, and provided clear delineation of the extent of varices and specific portosystemic collateral vessels. When duplex US was successful, there was full agreement with MR angiographic results in assessing portal vein patency and flow direction. All of the MR findings were corroborated at surgical exploration or autopsy. The authors conclude that MR angiography is very accurate in the portal system and is valuable in preoperative assessment for liver transplantation.  相似文献   
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From 1973 through 1983, 20 newborns with congenital duodenal atresia were treated. These patients are compared with our previous series and with other published series. There were no fatalities among the 19 patients who underwent operation, an improvement from the 72 percent survival rate in our previous series. Fifty-five percent of the patients had associated congenital anomalies, which frequently complicated their management. The use of a transanastomotic jejunal feeding tube resulted in delayed oral feeding and prolonged hospitalization, and cannot be recommended.  相似文献   
87.
A discussion of the present role of varicocele in the management of the subfertile couple is presented, with emphasis on detection techniques and the increasing awareness of the presence of bilateral varicocele. The indications and techniques of surgical management are discussed, with particular emphasis on the use of the operating microscope to dissect the spermatic cord at the level of the external inguinal ring under local anesthesia on an outpatient basis with significant cost savings to the patient.  相似文献   
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