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During 1994-1996 at the Clinic of Cardiovascular and Transplantation Surgery of IKEM 17 patients were operated with acute dissection of the thoracic aorta type A. Based on the applied surgical tactics the patients were retrospectively divided into two groups. The first included 8 patients where surgical reconstruction of the ascending aorta was implemented in the standard way, the second group comprised 9 patients where the method of deep hypothermia and circulatory arrest were used. Three operated patients died, all from the group with deep hypothermia. The cause of death was twice multiorgan failure and once haemorrhage in a female patient with cardiac tamponade before surgery. The authors discuss the advantages and some pitfalls of surgery in deep hypothermia and circulatory arrest and maintain that neurological disorders are most serious. In the conclusion they draw attention to some possible ways how to improve hitherto achieved results. They include e.g. reduction of the time interval between the development of symptoms of dissection and surgery, careful checking of the cooling and heating when using deep hypothermia, as well as better prevention of cerebral embolic attacks.  相似文献   
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OBJECTIVE: The objective of this study was to determine the outcome of early and late suture removal after the triple procedure (i.e., penetrating keratoplasty, cataract extraction, lens implant). DESIGN AND PARTICIPANTS: The refractive and keratometric results of 106 eyes undergoing the triple procedure were reviewed. The target postoperative refractive error was -1 diopter (D). RESULTS: Average length of follow-up was 40.3 months. Twenty eyes had sutures removed early (<18 months after surgery), 39 had sutures removed late (> or = 18 months after surgery), and 47 had sutures still intact at last follow-up. A best spectacle-corrected visual acuity of 20/40 or better was achieved in 90% of eyes with sutures removed early, 82.1% with sutures removed late, and 70.2% with sutures in place. For all eyes, the mean spherical equivalent at last follow-up was -2.50 D, with 75% of eyes falling between -4 and +2 D. The mean final refractive error was -3.40 +/- 3.53 D for eyes with sutures removed early and -1.79 +/- 3.99 D for eyes with sutures removed late. Eyes with sutures remaining had a mean final refractive error of -0.33 +/- 2.25 D. There was an overall decrease in refractive and keratometric astigmatism after both early and late suture removal with no significant difference between groups. However, there was a wide range of change with some eyes experiencing a decrease and others an increase in astigmatism. Mean postoperative K readings increased significantly for both groups after suture removal (final mean K, 47.00 D) but remained stable for eyes with sutures in. CONCLUSION: The authors data suggest that the final refractive error and net change in refractive and keratometric astigmatism after the triple procedure are not dependent on the timing of suture removal.  相似文献   
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A great deal of new information has become available in the field of hypertension since the JNC report of 1988. The JNC V report has changed the categorization of blood pressure, modified suggested drugs for initial therapy, and recommended that diuretics or beta blockers be considered the first-line drugs of choice. Information concerning the J curve and end-stage renal disease has made therapeutic goals more challenging. One of the most important additions to this report is the new information on treating elderly patients, which had been lacking until last year. The report calls on pharmacists to assist with detecting, evaluating, and referring hypertensive patients. Pharmacists must take a leadership role in promoting compliance with antihypertensive therapy and can assist other health-care professionals by suggesting therapeutic alternatives to improve efficacy, reduce the frequency of administration, and lower costs. The complete JNC V report is an essential reference for the files of any pharmacist who is responsible for the care of hypertensive patients.  相似文献   
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OBJECTIVE: We wished to determine the extent to which MR imaging contributes to the overall costs of imaging in the United States and to compare MR imaging costs with other imaging techniques. MATERIALS AND METHODS: All 23 current procedural terminology, version 4 (CPT-4) codes for MR imaging were extracted from the national 1993 Part B Medicare annual data reimbursement file. For each code, we calculated total Medicare physician reimbursements. Aggregate reimbursement for all MR imaging was compared with aggregate reimbursement for all 659 imaging-related current procedural terminology, version 4 codes and also with comparable figures for echocardiography and other categories of cardiovascular imaging. RESULTS: Within the 23 MR imaging codes, 1,449,911 examinations were performed on Medicare patients in 1993, for which physicians were reimbursed $370 million. Medicare reimbursement of physicians for all 659 imaging-related procedures was $5.3 billion. Thus, MR imaging accounted for only 7% of all imaging costs. By comparison, a group of just 10 imaging codes, which are primarily cardiovascular in nature, accounted for $1.67 billion, or 32% of the entire Part B costs for imaging. Reimbursements for echocardiography alone are more than twice those for MR imaging. CONCLUSION: From the national perspective, MR imaging does not appear to warrant its reputation as a costly procedure. The costs of echocardiography and other imaging related to the cardiovascular system are considerably higher.  相似文献   
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