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The incidence of penetrating wounds of the chest is rising rapidly. Opinions continue to differ on their management. Our experience with 200 consecutive cases of stab wounds of the chest between 1972 and 1975 were reviewed. There were 176 males and 24 females. The average age was 31 years; about two-thirds of the patients were under 30. About 74% presented with hemothorax or hemopneumothorax; 21 presented with pneumothorax. Eleven per cent had associated intra-abdominal injuries. Seventy-nine per cent were successfully treated with tube thoracostomy. About 15% underwent thoracotomy, with three deaths (mortality, 10%); the mortality for cardiac wounds was 16%; overall mortality was 1.5%. The overall complication rate was 5.5%, most occurring in patients with cardiac wounds and associated intra-abdominal injuries. The average period of hospitalization was 6.5 days. Treatment was individualized. Indications for each course of therapy are discussed. 相似文献
996.
The effect of temperature on the activity of galactosyl- and sialyltransferases of rat liver Golgi membranes and the galactosyltransferase of serum has been studied. Arrhenius plots for three enzymes were different. Sharp breaks in the curves, indicative of phase transitions were observed for sialyltransferase (28 degree C) of Golgi and galactosyltransferase (34 degree C) of serum but not for galactosyltransferase of Golgi. The activation energy was greater above the break (above 28 degree C) than below for sialyltransferase of Golgi; The activation energy was lower (above 34 degree C) for galactosyltransferase of serum than below. Electron microscopic freeze replicas showed a patchy distribution of particles which increased as the temperature was raised accompanied by smooth areas. This was interpreted as representing lateral phase separation of the membrane components. 相似文献
997.
998.
Early in the development of implant technology it became apparent that conventional dental imaging techniques were limited for evaluating patients for implant surgery. During the treatment planning phase, the recipient bed is routinely assessed by visual examination and palpation, as well as by periapical and panoramic radiology. These two imaging modalities provide a two-dimensional image of mesial-distal and occlusal-apical dimensions of the edentulous regions where implants might be placed. When adequate occlusal-apical bone height is available for endosteal implants, the buccal-lingual width and angulation of the available bone are the most important criteria for implant selection and success. However, neither buccal-lingual width nor angulation can be visualized on most traditional radiographs. Although clinical examination and traditional radiographs may be adequate for patients with wide residual ridges that exhibit sufficient bone crestal to the mandibular nerve and maxillary sinus, these methods do not allow for precise measurement of the buccolingual dimension of the bone or assessment of the location of unanticipated undercuts. For these concerns, it is necessary to view the recipient site in a plane perpendicular to a curved plane through the arch of the maxilla or mandible in the region of the proposed implants. Implant dentists soon recognized that, for optimum placement of implants, cross-sectional views of the maxilla and mandible were the ideal means of providing necessary pre-operative information. Today, the two most often employed and most applicable radiographic studies for implant treatment planning are the panoramic radiograph and tomography. Although distortion can be a major problem with panoramic radiographs, when performed properly they can provide valuable information, and are both readily accessible and cost efficient. To help localize potential implant sites and assist in obtaining accurate measurements, it is recommended that surgical stents be used with panoramic radiographs. In simple cases, where a limited number of implants are to be placed, panoramic radiography and/or tomography may be used to obtain a view of the arch of the jaw in the area of interest. For complex, cases, where multiple implants are required, the CT scan imaging procedure is recommended. Because of its ability to reconstruct a fully three dimensional model of the maxilla and mandible, CT provides a highly sophisticated format for precisely defining the jaw structure and locating critical anatomic structures. The use of CT scans in conjunction with software that renders immediate "treatment plans" using the most real and accurate information provides the most effective radiographic modality currently available for the evaluation of patients for oral implants. To follow patients after implant surgery, DSR can be helpful by addressing the limitations of other radiographic modalities in detecting postoperative changes. By eliminating unchanged information, DSR allows the clinician's eye to focus on actual changes that have occurred between the recordings of two images. 相似文献
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1000.
Two hundred and eight patients of low back pain were studied in the department of orthopaedic surgery, GSVM Medical College, Kanpur. The patients were put on intensive conservative treatment in the form of analgesics, hard bed rest, spinal extension exercises, traction and lumbosacral support. Thirty-two patients did not respond to this treatment and their symptoms were of more than 6 months duration and they were subjected to epidural injection of local anaesthetic agent, saline and corticosteroids. The failed 6 cases were investigated for consideration of surgery. The aim of this study is to develop standardised strategy for the treatment of low back pain. For the low back pain patients not responding to intensive conservative treatment, an idea has been put forward in the form of epidural medication prior to considering them to surgery to prevent unnecessary incidence of "failed back". A trial of epidural injection is suggested to avoid surgery. 相似文献