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The purpose of this study was to provide, in a large number of patients, comprehensive Doppler echocardiographic assessment of normal St Jude Medical mitral valve prosthesis function using Doppler-derived hemodynamic variables, including the mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio and prosthesis performance index. The pressure half-time was less than 130 milliseconds in all patients, and all but one patient had either a peak early mitral diastolic velocity of 2 m/s or less or a mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio of less than 2.2. There was a significant (P < .001) negative correlation between the prosthesis performance index and prosthesis size. This negative correlation suggests that there is more efficient use of the in vitro geometric orifice area with smaller prostheses.  相似文献   
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BACKGROUND: Staphylococcus aureus-associated peritonitis and catheter exit-site infections (ESIs) are important causes of hospitalization and catheter loss in patients undergoing chronic peritoneal dialysis. Intranasal and topical use of mupirocin has been found to be an effective strategy in decreasing S. aureus-related infectious complications in persons who are carriers of S. aureus; however, there is no consensus regarding the prophylactic use of mupirocin irrespective of carrier status. We aimed to determine the potential effectiveness of application of mupirocin cream at the catheter exit site in preventing ESI and peritonitis irrespective of carrier status in a tropical country such as India. METHODS: This prospective historically controlled study was done in a total of 40 patients. From August 2003, all patients, incident and prevalent, were instructed to apply 2% mupirocin cream daily to the exit site instead of the older practice of povidone-iodine and gauze dressing. Patients were not screened to determine whether they were S. aureus carriers. The infection-related data for 1 year, until July 2004, were compared with the historical control, which was infection-related data for the year preceding the year of mupirocin application. RESULTS: Mean age of the study population was 62 years, with 61.8% being male and 64.3% being diabetic. Local application of mupirocin led to a significant reduction in the incidence density per patient-month of both ESI and peritonitis compared to controls (0.15 vs 0.37 and 0.37 vs 0.67, p = 0.01 for both). This amounted to a relative reduction of 60.5% and 55% respectively. ESI and peritonitis due to S. aureus were also significantly lower in the study group compared to controls (incidence density per patient-month 0.05 vs 0.13 and zero vs 0.17 respectively, p < 0.01 for both). There occurred no catheter removal due to infection-related complications during the study period compared to two during the control period. None of the patients reported a mupirocin-related adverse effect. CONCLUSIONS: Daily application of mupirocin at the exit site is a well-tolerated and effective strategy in reducing the incidence of ESI and peritonitis in a tropical country such as India. It can thus significantly reduce morbidity, catheter loss, and transfer to hemodialysis in peritoneal dialysis patients.  相似文献   
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In order to assess the histological tissue changes over time around the site of implant, tissue biopsies were taken at 1 to 38 months post-implant from 54 (34 male) consenting human subjects who had received the Australian subcutaneous naltrexone-poly(DL-lactide) implant for heroin dependence. The implant consists of multiple tablets containing compressed naltrexone-poly[trans-3,6-dimethyl-1,4-dioxane-2,5-dione] (DL-lactide) loaded microspheres. Assessment of tissue samples by pathologists showed an early phase (up to 12 months post-implant) of inflammation, foreign body reaction, and fibrosis. This subsided gradually over the next 12 months until tissue returned to normal by 25+ months. Sufficient evidence was not available to conclude that the poly(DL-lactide) implant matrix was totally biodegradable within the study period. While implant material was not identified in most of the latter biopsies, its presence was noted in one biopsy at 26 months post-implant. Nevertheless the study results did demonstrate the implant's biocompatibility by the lack of inflammation, foreign body reaction, and fibrosis detected by 25+ months. It seems highly probable that surgical technique rather than the implant itself was associated with the additional finding of fat necrosis. Moderate fat necrosis was observed as a common feature of biopsies carried out during the first 6 months following implant. It subsided to mild levels over the next 18 months, and was notably absent by 25+ months. The results of the study indicated that the Australian naltrexone-poly(DL-lactide) implant is well tolerated and may have a role for use in the management of medical conditions such as heroin dependence.  相似文献   
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