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Image-directed percutaneous biopsies with a biopsy gun   总被引:3,自引:0,他引:3  
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method.  相似文献   
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Purification and characterization of potyvirus helper component   总被引:4,自引:1,他引:4  
Helper component (HC) was purified from tobacco vein mottling (TVMV)- and potato virus Y (PVY)- infected tobacco plants by sucrose gradient fractionation followed by affinity chromatography on oligo(dT)-cellulose and by gel electrophoresis. The subunit apparent molecular weights (M(r)) of the purified HCs were 53,000 (53K) and 58K for TVMV and PVY, respectively. Antisera to these purified polypeptides specifically blocked the activity of the homologous HC, as determined by aphid transmission assays, and specifically precipitated 75K products of the cell-free translation of the homologous RNA. The molecular weight of undissociated, biologically active TVMV or PVY HC, as determined by high-pressure liquid chromatography (HPLC)-gel permeation chromatography was found to be between 100K and 150K, suggesting that the active molecule is a dimer.  相似文献   
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 Whole-cell and inside-out patch-clamp techniques were used to assess the action of a well-known dye, Evans blue, on membrane currents in bladder isolated smooth muscle cells from sheep. In whole cells Evans blue dose-dependently increased the outward current by up to fivefold. In contrast, Evans blue had no effect on inward Ca2+ current. The effect on outward current was abolished or reduced if the cells were bathed in Ca2+-free solution, iberiotoxin (5 × 10–8 M), or charybdotoxin (5 × 10–8 M), but was unaffected by externally applied caffeine (5 mM) or in cells exposed to heparin (1 mg/ml) via the patch pipette. In inside-out patches bathed in a Ca2+ concentration of 5 × 10–7 M, Evans blue (10–4 M) increased the open probability of large-conductance (298-pS) Ca2+-dependent K+ channels (BK channels), shifting the half maximal-activation voltage by –70 mV. We conclude that Evans blue dye acts as an opener of BK channels. Received: 1 September 1997 / Received after revision: 18 November 1997 / Accepted: 20 November 1997  相似文献   
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Osteosarcomatosis   总被引:10,自引:0,他引:10  
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.  相似文献   
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Role of epidural medication through caudal route was studied in 109 patients having lumbago with or without sciatica to highlight the value of this mode of treatment which relieved symptoms in more than 70% of cases without hospitalisation and without being off work for long periods as in usual methods of conservative treatment.KEY WORDS: Epidural medication, Backache, Lumbago, Sciatica  相似文献   
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