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Fibromuscular dysplasia is the second commonest anatomical abnormality apart from multiple renal arteries in the potential live donors. Pretransplant evaluation of the donors may include an angiography to evaluate the renal arteries, and failure to recognize renal arterial stenosis, particularly fibromuscular dysplasia, by noninvasive methods may eventually lead to hypertension and ischemic renal failure. We report a case of fibromuscular dysplasia that was undetected by computed tomographic angiography prior to donation. One year after kidney donation, it rapidly progressed to severe symptomatic stenosis with hypertension and acute renal failure. Following renal artery angioplasty, her blood pressure normalized over a period of 2 weeks without any need for antihypertensive medications and the serum creatinine returned to her baseline. The acceptability of renal donors with fibromuscular dysplasia depends on the age, race and the availability of the other suitable donors. Mild fibromuscular dysplasia in a normotensive potential renal donor cannot be considered a benign condition. Such donors need regular follow-up postdonation for timely detection and treatment.  相似文献   
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We present a proof that the mean open (and closed) times of the individual channels in a multichannel record can be found in a model-independent fashion. As the results are model independent, they can be derived by assuming the simplest model for all the channels, namely that they all have the basic CLOSED in equilibrium with OPEN scheme. In particular, the method can be applied to patches where the channel population is heterogenous with respect to open probability. Multichannel simulations are performed to test the limits of applicability of this method to restricted amounts of data. One conclusion is that increasing the number of channels does not substantially reduce the errors in estimating the mean times, in spite of the 'increased information' present. We also prove the general applicability of the algorithm of Fenwick et al. (1982) in estimating the mean times without knowledge of the number of channels present, and discuss its limitations. An illustration using experimental data is also given.  相似文献   
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The dispensable N-terminus of iso-1-cytochrome c (iso-1) in the yeast Saccharomyces cerevisiae was replaced by 11 different amphipathic structures. Rapid degradation of the corresponding iso-1 occurred, with the degree of degradation increasing with the amphipathic moments; and this amphipathic-dependent degradation was designated ADD. ADD occurred with the holo-forms in the mitochondria but not as the apo-forms in the cytosol. The extreme mutant type degraded with a half-life of approximately 12 min, whereas the normal iso-1 was stable over hours. ADD was influenced by the +/ state and by numerous chromosomal genes. Most importantly, ADD appeared to be specifically suppressed to various extents by deletions of any of the YME1, AFG3, or RCA1 genes encoding membrane-associated mitochondrial proteases, probably because the amphipathic structures caused a stronger association with the mitochondrial inner membrane and its associated proteases. The use of ADD assisted in the differentiation of substrates of different mitochondrial degradation pathways.  相似文献   
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Morphologic features of Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) overlap. No single phenotypic marker or molecular abnormality is pathognomonic. We tested a panel of 8 germinal center (GC) and activated B-cell (ABC) markers for their ability to separate BL and DLBCL. We diagnosed 16 BL and 39 DLBCL cases from 21 patients with AIDS and 34 without AIDS based on traditional morphologic criteria, Ki-67 proliferative index, and c-myc rearrangement (fluorescence in situ hybridization). After immunohistochemically staining tissue microarrays of BL and DLBCL for markers of GC (bcl-6, CD10, cyclin H) and ABC (MUM1, CD138, PAK1, CD44, bcl-2), we scored each case for the percentage of positive cells. Hierarchical clustering yielded 2 major clusters significantly associated with morphologic diagnosis (P < .001). For comparison, we plotted the sum of the GC scores and ABC scores for each case as x and y data points. This revealed a high-GC/low-ABC group and a low-GC/high-ABC group that were associated significantly with morphologic diagnosis (P < .001). Protein expression of multiple GC and ABC markers can separate BL and DLBCL.  相似文献   
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BackgroundTreatment options for metastatic osseous lesions of the proximal femur include hemiarthroplasty (HA) or total hip arthroplasty (THA) depending on lesion characteristics and patient demographics. Studies assessing short-term outcomes after HA/THA in this patient population are limited. Therefore, the purpose of this present study was to identify short-term rates of morbidity and mortality after HA/THA for pathological proximal femur fractures, as well as readmission and reoperation rates and reasons.MethodsThis study utilized a large, prospectively collected registry to identify patients who underwent HA/THA between 2011 and 2018. Patients were stratified by indication for surgery, including pathological fracture, nonpathological fracture, and osteoarthritis. Baseline patient characteristics and postoperative complications were compared using bivariate and/or multivariate analysis.ResultsIn total, 883 patients undergoing HA/THA for a pathological fracture were identified. Relative to an osteoarthritis cohort, these patients tended to be older, had a lower body mass index, and had significantly more preoperative comorbidities. These patients had high rates of total complications (13.93%), including thirty-day mortality (3.29%), unplanned return to the operating room (4.98%), and pulmonary complications (3.85%). Patients with pathological fracture had a longer operative duration relative to osteoarthritis and nonpathological cohorts (+27 and +25 minutes, respectively), despite having high rates of HAs performed.ConclusionPatients undergoing hip arthroplasty for pathologic proximal femur fracture have increased morbidity and mortality relative to an osteoarthritis cohort. However, patients with a pathological fracture have similar rates of morbidity and mortality when compared with a nonpathological fracture cohort, but did experience higher rates of perioperative blood transfusion and unplanned readmissions.Level of EvidenceIII.  相似文献   
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The COVID-19 pandemic has affected the ability of the sports medicine physician to be present to participate in in-person sideline evaluation of the injured athlete. The purpose of this review is to assess existing literature regarding the utilization of telehealth for sideline evaluation and management of the injured athlete, as well as to identify further areas of research. With the rapid incorporation of telehealth visits, the utilization and capabilities of telemedicine continue to expand. A number of evidence-based resources are available to support medical providers to develop and utilize video evaluation for the sideline evaluation of sports-related injuries. Future research, including the development of validated, modified examination techniques and technologies, will allow for improved interactive physical examinations, which may be better utilized for sideline evaluation.  相似文献   
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Use of methotrexate in juvenile idiopathic arthritis.   总被引:8,自引:0,他引:8  
Methotrexate (MTX) has transformed the outlook for children with juvenile idiopathic arthritis (JIA). Most of the evidence from uncontrolled clinical trials suggests that MTX is an effective agent for treating active JIA. Data from controlled clinical trials suggests that MTX has statistically significant effects on patient centred disability measures in JIA patients with active arthritis. Although we would like a much larger study directed evidence base for our use of the drug, the studies that have been done are sound and have been followed by a change in clinical expectations and advice that speak of qualitative evidence from clinical practice, confirming the scientifically acquired data. Randomised controlled multicentre trials using sufficient numbers of patients, including functional assessment and quality of life measures, are needed to confirm the long term efficacy and safety of MTX in JIA.  相似文献   
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