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Using an immunoradiometric assay, Cathepsin D (Cath D) levels were measured in the cytosol of 23 normal and 39 neoplastic human laryngeal tissues. Scattered Cath D levels (from 2.2 to 17.8 pM/mg protein; median = 7.6) were found in normal mucosa specimens. Cath D concentrations range from 2.0 to 29.3 pM/mg protein (median = 8.5) in laryngeal tumors. When a comparison between Cath D levels in normal and neoplastic tissue specimens from the same patient was done, Cath D levels were significantly higher in laryngeal cancers than in their normal counterparts (P = 0.03). No correlation with clinico-pathological parameters and steroid hormone and epidermal growth factor receptor status was found. Further studies should investigate whether the production of Cath D by laryngeal tumors could have a clinical relevance for this neoplasia.  相似文献   
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A technique for performing core biopsies of indeterminate masses of the extracranial head and neck is described. Four patients with suspicious masses of the extracranial head and neck underwent coaxial core biopsies through an 18-gauge Hawkins-Akins blunt tip needle. Three of the four patients had diagnostically adequate samples. There were no neurologic or vascular complications.  相似文献   
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PURPOSETo present the spectrum of CT and MR findings of glomus tumors of the head and neck successfully treated with radiation therapy.METHODSThe patient charts and all CT and MR studies of 24 patients (25 tumors) who had been successfully treated with radiation therapy were retrospectively reviewed. Eighteen patients had pre- and posttreatment imaging studies. Tumor size, internal morphology, enhancement pattern, visualization of flow voids, and bone erosion were evaluated before and after radiation therapy. Statistical evaluation of the presence of flows voids and tumor size was performed using the Fischer Exact Test.RESULTSAll patients had residual tumor after radiation therapy. Sixty-one percent of tumors demonstrated a reduction in size. Only one tumor with pretreatment bone destruction demonstrated healing of the bone. MR findings after radiation therapy included variable alteration in T2 signal, decreased heterogeneous enhancement, and a reduction in flow voids. There was a significant difference in the presence of flow voids based on tumor size.CONCLUSIONSSuccessfully irradiated paragangliomas demonstrate residual masses, the presence of which does not by itself indicate treatment failure. Stabilization or reduction in size, decreased enhancement, diminished flow voids, and reduced T2 signal after radiation therapy are a result of therapy and are indicative of local control. Persistent bone demineralization and erosion without progression is commonly seen in successfully controlled tumors. Paragangliomas are relatively homogeneous in internal morphology except for areas of flow void. Flow voids are not a reliable criterion for diagnosis in lesions less than 2.5 cm.  相似文献   
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Symptomatic biliary leakage following major upper abdominal surgery is a severe complication resulting in increased morbidity and mortality. Treatment options usually include either endoscopic intervention or surgical revision. These options may be burdened by a high perioperative risk for the patient (e.g., patients with severe disease) or simply may not be possible (e.g., nonpreserved gastroduodenal passage). In the past, percutaneous transhepatic cholangiodrainage did only seem to be a viable option for patients with dilated bile ducts. Here, we present our experience in a consecutive series of patients with symptomatic biliary leakage following major upper abdominal surgery and without dilation of the biliary system that underwent percutaneous transhepatic cholangiodrainage. Percutaneous transhepatic cholangiodrainage was feasible in 15 of 18 patients (83.3%). The procedure was technically not possible in three patients (16.7%). In 10 of the 15 patients (66.6%) with feasible percutaneous transhepatic cholangiodrainage, biliary leakage was definitely controlled without the need for surgical revision. Depending on the experience with the interventional procedure, percutaneous transhepatic cholangiodrainage should be considered as an alternative for treatment of symptomatic biliary leakage instead of immediate reoperation. Presented at the Digestive Disease Week 2005 (DDW), Chicago, IL, May 14–19, 2005 (poster presentation).  相似文献   
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Rapidly changing perspectives about mast cells at mucosal surfaces   总被引:2,自引:0,他引:2  
Summary: Mast cells (MCs) are major effector cells of immunoglobulin E (IgE)‐mediated allergic inflammation. However, it has become increasingly clear that they also play important roles in diverse physiological and pathological processes. Recent advances have focused on the importance of MCs in both innate and adaptive immune responses and have fostered studies of MCs beyond the myopic focus on allergic reactions. MCs possess a variety of surface receptors and may be activated by inflammatory mediators, IgE, IgG, light chains, complement fragments, proteases, hormones, neuropeptides, and microbial products. Following activation, they produce a plethora of pro‐inflammatory mediators and participate in inflammatory reactions in many organs. This review focuses on the role of MCs in inflammatory reactions in mucosal surfaces with particular emphasis on their role in respiratory and gastrointestinal inflammatory conditions.  相似文献   
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