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Transplant atherosclerotic coronary disease remains the leading cause of death in heart transplant recipients. We report the first case of coronary stent implantation in a heart graft for epicardial focal stenosis. Due to the lower rate of restenosis after stenting in the native coronary artery, we suggest that coronary stenting be considered an acceptable, first intention therapeutic option instead of angioplasty alone whenever possible.  相似文献   
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Nodular regenerative hyperplasia (NRH), a rare condition that is commonly associated with noncirrhotic portal hypertension, is not well described in the MR literature. Three patients at two institutions were identified who had both abdominal MR imaging and pathologic evidence of NRH. All examinations were performed at 1.5 T and included axial T1- and T2-weighted spin-echo (SE) images. The MR studies were reviewed by two radiologists in consensus. Two patients had multiple liver lesions that had high signal components on T1-weighted images and were predominantly isointense with liver on the T2-weighted images. One patient had no focal lesions identified. NRH, when visualized on MR images, appears as multifocal masses with shortened Tl and T2 similar to liver. NRH should be considered in the differential diagnosis of hepatocellular tumors, especially in patients with a predisposing condition.  相似文献   
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The CD16: ζ: γ receptor complex allows natural killer (NK) cells to recognize and eliminate antibody-coated target cells. Whereas the ectodomain of CD16 is the receptor for Fcγ domains of immunoglobulins, disulfide-linked homo- and heterodimers composed of ζ and γ are required for the cell surface expression, and signal transduction properties of the complex. Engagement of CD16 activates the tyrosine kinase pathway, which induces the tyrosine phosphorylation of several substrates, including the ζ subunit and the phospholipase C γ-1 and γ-2 isoforms. Here we show that CD 16 stimulation of either peripheral blood NK cells, leukemic NK cells, or Jurkat transformants expressing a CD16:ζ:γ receptor complex, results in the tyrosine phosphorylation of a 70 kDa ζ-associated protein (pp70). Similarly, a 70-kDa ζ-associated phosphoprotein in T cells has been shown to be a tyrosine kinase (ZAP-70). Peptide mapping analysis indicates that the 70-kDa ζ-associated phosphoproteins from T cells and NK cells are structurally indistinguishable. We conclude that the CD16:ζ:γ complex may use a ZAP-70-related non-receptor tyrosine kinase, in the CD16 signaling cascade leading to NK cell activation.  相似文献   
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Study Objective . To determine if one commercial extended-release formulation of nifedipine (Adalat CC) is as effective as another (Procardia XL) in controlling blood pressure over 24 hours. Design . Open-label, randomized, crossover study. Setting . University-affiliated family medicine clinic. Patients . Fifteen patients with stage 1–4 primary hypertension. Interventions . Procardia XL or Adalat CC once/day was titrated to achieve blood pressure control. The effective dose was continued for 4 weeks, washed out for 1 week, and reinstituted with other study drug. Measurements and Main Results . Twenty-four-hour ambulatory blood pressure was recorded the conclusion of each treatment phase. Treatment phases were compared for mean 24-hour blood pressure, mean daytime (6:00 a.m.–10:00 p.m.) and mean nighttime blood pressure, and mean blood pressure load (percentage of blood pressure measurements < 140/90 mm Hg daytime and > 120/80 mm Hg nighttime). Thirteen patients completed the study. No statistically significant difference was seen in mean 24-hour blood pressure (138/86 mm Hg for Procardia XL vs 137/85 mm Hg for Adalat CC), daytime or nighttime blood pressure, or blood pressure load. Two patients experienced clinically significant adverse effects while taking Adalat CC. Conclusions . In these patients with primary hypertension, Adalat CC was as effective as Procardia XL at controlling blood pressure for 24 hours. Blood pressure, heart rate, and adverse effects should be monitored 2–4 weeks after any exchange of Adalat CC for Procardia XL.  相似文献   
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PURPOSE: This article provides a review of the disarticulation resection of the mandible for various benign and malignant tumors and non-neoplastic processes. In so doing, the author proposes a classification to describe extension of pathology into the condylar region, thereby requiring its sacrifice. Recommendations are also proposed for preservation versus sacrifice of the meniscus when performing a disarticulation resection of the mandible. Finally, complications are evaluated in this type of mandibular resection. PATIENTS AND METHODS: This review is based on the author's accumulated clinical data obtained from performing disarticulation resections on 16 patients who presented with 10 different pathologic diagnoses. Disarticulation resections are performed for 3 different patterns of extension of pathologic processes into the condylar region, designated as type I, type II, and type III by the author. These designations reflect the radiographic involvement of the condyle or subcondylar region of the mandible by the pathologic entity. The designations of type II and type III extensions are diagnosis dependent, whereas type I extension is independent of diagnosis. RESULTS: Five patients in this series presented with type I condylar extension, 2 patients presented with type II condylar extension, and 9 patients presented with type III condylar extension. The meniscus required sacrifice in 3 of the 16 patients. Complications occurred in 3 of 16 patients and included 1 dislocation of the plate into the middle cranial fossa, 1 dislocation of the plate inferiorly and posteriorly to the mastoid process, and 1 cutaneous exposure of the plate. CONCLUSIONS: Disarticulation resections are rarely required variants of segmental resection of the mandible, and they are required by a variety of pathologic processes of the jaws and contiguous structures. The placement of a reconstruction bone plate with an affixed condylar prosthesis is well tolerated by patients and is associated with few complications. These reconstruction bone plates favorably support facial form, symmetry, and occlusion such that many patients delay their definitive bony reconstruction. Because these condyles are temporary prostheses, the surgeon should consider their removal with bony reconstruction of the disarticulation defect as soon as possible after the ablative surgery.  相似文献   
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