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151.
A simplified method for automated red blood cell processing is described. The method uses sterile, disposable plastic centrifuge bowls with attached tubing and reagent solutions. It can be used for the separation of red blood cells and plasma and the glycerolization and deglycerolization of red blood cells for storage in the frozen state. Data is presented on operational performance of the equipment and on red blood cell yields and post-thaw transfusion survival.  相似文献   
152.
BACKGROUND: Some studies have claimed that patients with immunoglobulin A (IgA) nephropathy have better graft survival than other renal graft recipients, whereas others have rejected this statement. We have addressed this paradox in the present study. METHODS: In all, 1,207 patients with IgA nephropathy who received a primary cadaveric renal graft from 1990 to 2002 were identified in the Eurotransplant database. For comparison, we analyzed 7,935 patients with nonglomerular diseases. Death-censored graft survival was calculated using Kaplan Meier estimates and a multivariable Cox regression analysis was used for risk calculations. RESULTS: Death-censored graft survival was superior in patients with IgA nephropathy in the first period after transplantation. After 3 years posttransplant, however, there was an accelerated decline in graft survival in recipients with IgA nephropathy. The fully adjusted risk of graft loss in the first year was increased by 40% in the control group compared to IgA nephropathy (hazard ratio [HR] 1.40, 95% CI 1.12-1.75), whereas the risk was significantly lower in the control group after the first year posttransplant (HR 0.75, 95% CI 0.63-0.88). Cold ischemia time, immunization and HLA-DR mismatch were risk factors for graft loss in the control group but not for IgA nephropathy, whereas HLA-AB mismatch was an independent risk factor, exclusively for the IgA nephropathy group. CONCLUSIONS: Recipients with IgA nephropathy have better 1-year graft survival, presumably due to favorable immunological behavior. This benefit was however abolished in the long-term by increased graft loss with time. Studies are needed to explain the difference in graft survival and the reason why different risk factors are involved in graft failure.  相似文献   
153.
The purpose of this study was to assess the technical feasibility and early outcome of tibial angioplasty for a subset of patients with limb-threatening ischemia who were not candidates for bypass grafting. A retrospective analysis was conducted of 19 patients (7 male, 12 female) who underwent crural angioplasty for limb-threatening ischemia using 0.018- or 0.014 inch-based systems. Contraindications to bypass were insufficient conduit in 7 patients and severe comorbid illness in 12. Concurrent treatment of inflow lesions was performed in 12 of 20 limbs via either angioplasty alone (5) or combined with stenting (12). Outcome measures were anklebrachial indices (ABI), relief of rest pain, and healing or healed wounds. Twenty-three vessels were treated, including 14 tibial occlusions and 9 stenoses. The average length of diseased segment was 11 cm (range, 3-25 cm). Thirteen of 14 occlusions were treated with subintimal recanalization, the remainder with laser recanalization. Technical success was achieved in 22 of 23 treated vessels. Mean preoperative ABI was 0.53 and mean postoperative ABI was 0.85. Palpable pulses were present in 11 of 20 limbs (55%). There was one perioperative mortality (5.2%). Mean follow-up was 3 months. Three failures occurred requiring amputation (15.8%). The remaining 16 patients were improved with healing (8) or healed (4) wounds and relief of rest pain (4). These results indicate that technical success may be achieved with outflow lesion angioplasty in the majority of patients encountered. The durability of this method of therapy is unknown, and our length of follow-up is not sufficient to answer this question. However, an attempt at angioplasty appears justified before primary amputation and before surgical bypass in those patients at high risk for intervention.Presented at the 17th Annual Meeting of the Eastern Vascular Society, New York, NY, May 1-5, 2003.  相似文献   
154.
BACKGROUND: Computed tomographic (CT) head scanning of blunt trauma patients is expensive, delays care, and necessitates radiation exposure, while detecting intracranial injuries in a minority of patients. Clinical characteristics may be able reliably identify patients who do not have intracranial injuries and consequently, do no require imaging. METHODS: Physicians assessed blunt trauma patients undergoing imaging for the presence or absence of specific criteria. Recursive partitioning was used to identify criteria that predict intracranial injuries with high sensitivity. RESULTS: Intracranial injuries were found in 917 of 13,728 enrolled patients (6.7%). Injuries were rare among patients under age 65 who had no evidence of skull fracture, scalp hematoma, neurologic deficit, abnormal alertness, abnormal behavior, coagulopathy, or persistent vomiting. These characteristics would have identified 901 injury cases (sensitivity 98.3% [CI: 97.2-99.0]), while classifying 1,752 patients (12.8%) as "low risk." CONCLUSIONS: Clinical characteristics can reliably identify patients who are unlikely to have intracranial injuries and who do not require CT imaging.  相似文献   
155.
Although HLA matching is beneficial in clinical transplantation, it is not feasible to select a completely HLA matched donor for every potential recipient because of the enormous polymorphism of the HLA system. As a consequence, the majority of the recipients will be transplanted with a mismatched donor organ or hematopoietic stem cell transplant. For this large group of patients it is important to take advantage of the differential immunogenicity of HLA mismatches and to select for them a donor with HLA mismatches of low immunogenicity, the so-called acceptable mismatches. The differential immunogenicity of HLA mismatches can be determined by either retrospective analysis of graft survival data or by in vitro assays measuring T-cell and B-cell alloreactivity. A recently developed computer algorithm (HLAMatchmaker) can be instrumental in selecting donors with HLA mismatches, which do not lead to alloantibody formation. The theoretical background and practical implications of this acceptable mismatch approach are discussed.  相似文献   
156.
BACKGROUND: There are limited data regarding implantable cardioverter defibrillator (ICD) therapy in postinfarction women with severe left ventricular dysfunction. The aim of this study was to evaluate the risk of cardiac events and effects of ICD therapy in women as compared to men enrolled in the Multicenter Automatic Defibrillator Implantation Trial II (MADIT II). METHODS AND RESULTS: Among 1,232 patients enrolled in MADIT II, there were 192 (16%) women and 1,040 (84%) men. When compared to men, women had an increased frequency of NYHA class > or =II (70 vs 63%; P = 0.067), hypertension (60% vs 52%; P = 0.047), diabetes (42% vs 34%; P = 0.027), and LBBB (25% vs 17%; P = 0.011), and less frequent CABG surgery (42% vs 60%; P < 0.001). The 2-year cumulative mortality in patients randomized to conventional therapy was not significantly different in women and men (30% and 20%, respectively; P = 0.19). Adjusting for relevant clinical covariates, the hazard ratios for ICD effectiveness were similar in women (0.57; 95% CI = 0.28-1.18; P = 0.132) and men (0.66; 95% CI = 0.48-0.91; P = 0.011). The risk of appropriate ICD therapy for VT/VF was lower in women than in men (hazard ratio = 0.60 for female vs male gender; 95% CI = 0.37-0.98; P = 0.039). CONCLUSIONS: MADIT II women had similar mortality and similar ICD effectiveness when compared to men. MADIT II women with ICDs had a lower risk of arrhythmic events with fewer episodes of ventricular tachycardia than men.  相似文献   
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159.
An arteriovenous fistula between the systemic and pulmonary circulations may be congenital, as in bronchopulmonary sequestration, or the communication may be acquired. Inflammatory disease, trauma, and, rarely, neoplasm have been implicated as possible causes of acquired communications. We describe a patient who had a systemic artery-to-pulmonary vein fistula that was secondary to a recurrent sarcoma of the chest wall. Review of the literature failed to reveal a previous report of a similar case.  相似文献   
160.
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