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1.
The carpal regions of ten cadaver extremities were imaged by CT. The images were combined into a 3-dimensional model of the carpus using a technique based on a dynamic programming algorithm to find an optimal estimate of the location of the bone boundaries in the CT images. The resulting set of surface points on each bone was used to compute volumes and principal and antipodal axes for the bones. A spatial coordinate system was established based on the positions of the centroids of three bones in the distal carpal row. The angular orientations of all carpal bones were determined with respect to this system. The principal axes for the same bone among ten wrist specimens proved to be more widely dispersed than the antipodal axes for the same bones. The antipodal axes also correspond more closely to an intuitive notion of the “longest axis” of the bones. We conclude that the antipodal axis is a more reliable and useful measure of bone orientation than the principal axis.  相似文献   
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Lumbar subarachnoid catheterization in rats   总被引:3,自引:0,他引:3  
An animal model was developed for the study of subarachnoid (spinal) anesthesia and analgesia under unanesthetized, unsedated and unrestrained conditions. Sprague-Dawley rats were anesthetized with intraperitoneal ketamine (75-100 mg.kg-1). A PE10 catheter was inserted under direct vision into the lumbar subarachnoid space, through partial laminectomy of L1 or L2 with or without removal of adjacent intervertebral ligament. One week after surgery, correct position of the catheter was verified by subarachnoid injection of 0.03-0.05 ml of 1.5% lidocaine, which produced temporary hind limb paralysis in all but one animal in 28 consecutive operations. There was neither mortality nor major complication, intraoperatively or postoperatively. Only 2 animals developed minor subcutaneous would infections which responded to incision, drainage and debridement.  相似文献   
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BACKGROUND: Purinergic receptors are cell-surface molecules that bind extracellular nucleotides, notably ATP. The P2X family includes seven nonselective ion channels with one member, P2X(7), implicated in cytolytic pore formation and cell death. MATERIALS AND METHODS: We sought P2X(7) expression in mouse nephrogenesis and cpk/cpk renal cyst growth, conditions in which both proliferation and apoptosis are prominent. RESULTS: P2X(7) immunolocalized to condensed metanephric mesenchyme: both proliferation and apoptosis were detected in this compartment, assessed by proliferating cell nuclear antigen expression and propidium iodide-stained pyknotic nuclei respectively. Later in nephrogenesis, P2X(7) was detected in collecting ducts, a pattern persisting to maturity. A mesenchymal to epithelial shift of P2X(7) expression was also documented in ureter development. In cpk/cpk kidneys, P2X(7)-expressing collecting duct cysts dominated histology from two weeks until four weeks after birth, when animals die from uremia. In polycystic kidneys pyknotic nuclei were rarely identified in P2X(7)-expressing epithelia, but were detected between cysts, consistent with a non-apoptotic role for P2X(7) in cyst enlargement. CONCLUSION: P2X(7) is expressed during normal nephrogenesis and in a model of congenital polycystic kidney disease. Further experiments are necessary to define possible functions of P2X(7) in these settings.  相似文献   
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Most publications citing the effectiveness of renal extracorporeal shock wave lithotripsy have used plain abdominal radiography to assess residual calculi after treatment. We compared radiologist sensitivity and specificity in the detection of calculi on plain abdominal radiographs versus conventional film-screen and digital renal tomograms in extracorporeal shock wave lithotripsy patients. Of the patients 50 were imaged before and within 24 hours after lithotripsy. Six radiologists evaluated the resultant 300 studies for the presence and location of calculi. The mean sensitivity for digital tomograms was 83% for pre-lithotripsy and post-lithotripsy studies, which was significantly higher than for plain abdominal radiography and conventional tomography after lithotripsy. However, there were significantly more false positive stone diagnoses associated with digital tomogram interpretation. Signal detection analysis verified the over-all superiority of digital tomography for post-extracorporeal shock wave lithotripsy imaging. Calculus detection by conventional and digital tomography is superior to detection by plain abdominal radiography. However, because we did not perform delayed imaging, it is not possible to say what impact digital tomography might have on the management of extracorporeal shock wave lithotripsy patients.  相似文献   
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汪南华  王锐  冷宗康  彭司勋 《药学学报》1990,25(12):920-925
缩氨基硫脲类化合物有抗肿瘤、抗病毒和抗菌等多种药理活性。Barret等首次报道了乙二醛二缩氨基硫脲(Ⅰ)的抗疟活性。Klayman等研究了缩  相似文献   
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Factors influencing women to undergo screening mammography   总被引:2,自引:0,他引:2  
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This article reviews the author's experience with a form of interposed abdominal compression cardiopulmonary resuscitation (IAC-CPR) in the United Kingdom. The development of the technique based upon animal resuscitation, including the use of phasic compression (abdominal pumping) for the resuscitation of rats from 30 minutes of cardiac arrest due to hypothermia, is reviewed. A simple technique for clinical use is described. The technique uses a hard-covered book or bean-shaped board applied to the abdomen below the umbilicus and compressed alternately with cardiac massage while respiration is assisted. Anecdotal clinical results suggest that further controlled clinical investigation is warranted.  相似文献   
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