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941.
942.
943.
This report looks at outpatient treatment of nasopharyngeal inlet stenosis, a more commonly seen postoperative complication of uvulopalatopharyngoplasty (UPPP). It does not study the effectiveness of the UPPP for treatment of obstructive sleep apnea syndrome (OSAS). The authors evaluated six patients who had a UPPP for OSAS, all of whom developed stenosis in the nasopharyngeal inlet ranging from 14 mm to complete closure. Two patients had failed rotation flap repairs. The carbon dioxide laser was used to treat these patients in the office under a local anesthesia in a staged manner. We now have patients from 3 months to 12 months follow-up who have had stenosis treated successfully. We believe that the postoperative complication of nasopharyngeal inlet stenosis after UPPP can be treated in a safe and cost-effective manner in the office setting.  相似文献   
944.
945.
Longitudinal growth of bone involves a complex sequence of cellular events in the cartilaginous epiphysis. Whole blood serum has been shown previously to be a potent stimulus to the cells of the growth plate, as demonstrated by its ability to activate the inositol phosphate-calcium second messenger system resulting in a rise in intracellular Ca2+. By manipulating the preparation of serum to functionally separate it into its constituent parts, we have shown that the processes of platelet lysis and activation of the clotting cascade are responsible for the generation of factors that stimulate this signaling mechanism in isolated bovine growth plate chondrocytes. Through a subsequent trial of bioactive agents generated in these processes, we identified and partially characterized several novel agonists of growth plate chondrocytes: adenosine triphosphate and adenosine diphosphate, the purine energy substrates, and bradykinin, the bioactive peptide generated in a side reaction of the clotting cascade, each induces a rise in intracellular Ca2+ via release from intracellular ion stores. Additionally, the three distinct isoforms of platelet-derived growth factor (AA, AB and BB), also released on platelet lysis, were compared with respect to their ability to stimulate the inositol phosphate-calcium second messenger system in growth plate chondrocytes.  相似文献   
946.
947.
The high cost of commercial CT-compatible stereotactic frames has restricted the availability of CT-guided stereotaxy for many neurosurgical centres. However, many of these centres do possess the standard stereotactic frames for projection radiography, of which the old type Leksell frame is probably the most common. We have devised a simple and low-cost modification to an old Leksell frame to allow CT-guided stereotaxy. The nature of the modifications allow complete freedom of positioning of the frame relative to the CT scanner and coordinate transformations can be performed simply and effectively. The modified frame has been used successfully for some 18 months and the modification has now been performed at two centres in the North West Regional Health Authority. We hope this modification will allow many other centres to embark on CT-guided stereotaxy.  相似文献   
948.
The coexistence of otosclerosis and endolymphatic hydrops in the temporal bone have been described; however, the mechanism for the development of endolymphatic hydrops in otosclerosis remains unknown. Among 128 temporal bones with otosclerosis, involvement of the vestibular aqueduct by otosclerosis was observed in four temporal bones from two patients. In all four, the vestibular aqueduct was filled with active otosclerotic foci; the lumen of the endolymphatic duct and sac was narrowed as a result of fibrosis, and endolymphatic hydrops, more severe in the pars inferior than the pars superior, was observed. Collapse of the ductus reuniens and dilated saccule was seen in three temporal bones. Our study indicates that otosclerotic obstruction of the vestibular aqueduct may create a disturbance of the outflow and/or absorption of endolymph, leading to the development of endolymphatic hydrops and Meniere's disease, thus supporting the theory of longitudinal flow of endolymph.  相似文献   
949.
Cholesterol granuloma of the peritoneum   总被引:1,自引:0,他引:1  
Cholesterol granulomas are common in the mastoid region but have rarely been reported in other areas. The authors report the case of a 40-year-old man who had a cholesterol granuloma of the peritoneum. They discuss the morphology of the condition and the difficulties of diagnosis. It is likely that chronic or recurrent inflammation plays a major role in the pathogenesis and that, when dealing with such lesions preoperatively or intraoperatively, a radical approach may not be necessary.  相似文献   
950.
Sett  P. K.  Crockard  H. A.  Powell  M.  Lightman  S.  Jacobs  H. 《Acta neurochirurgica》1990,102(1-2):69-72
Summary Two cases of meningiomas, which are considered to have been caused by the preceding irradiation, are reported. In both cases, the cytokinetic study of the tumour using bromodeoxyuridine (BrdU) was performed. The percent of the tumour cells in the S phase of the cell cycle was less than 1% in both cases. The low labelling indices might suggest a relatively slow growing potential of these tumours, though the radiation-induced meningiomas were reported as being rapidly growing and malignant.  相似文献   
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