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31.
The Broad Spectrum of Quality in Deceased Donor Kidneys 总被引:7,自引:6,他引:1
Jesse D. Schold Bruce Kaplan Rajendra S. Baliga Herwig-Ulf Meier-Kriesche 《American journal of transplantation》2005,5(4):757-765
The quality of the deceased donor organ clearly is one of the most crucial factors in determining graft survival and function in recipients of a kidney transplant. There has been considerable effort made towards evaluating these organs culminating in an amendment to allocation policy with the introduction of the expanded criteria donor (ECD) policy.
Our study, from first solitary adult deceased donor transplant recipients from 1996 to 2002 in the National Scientific Transplant Registry database, presents a donor kidney risk grade based on significant donor characteristics, donor–recipient matches and cold ischemia time, generated directly from their risk for graft loss. We investigated the impact of our donor risk grade in a naïve cohort on short- and long-term graft survival, as well as in subgroups of the population.
The projected half-lives for overall graft survival in recipients by donor risk grade were I (10.7 years), II (10.0 years), III (7.9 years), IV (5.7 years) and V (4.5 years). This study indicates that there is great variability in the quality of deceased donor kidneys and that the assessment of risk might be enhanced by this scoring system as compared to the simple two-tiered system of the current ECD classification. 相似文献
Our study, from first solitary adult deceased donor transplant recipients from 1996 to 2002 in the National Scientific Transplant Registry database, presents a donor kidney risk grade based on significant donor characteristics, donor–recipient matches and cold ischemia time, generated directly from their risk for graft loss. We investigated the impact of our donor risk grade in a naïve cohort on short- and long-term graft survival, as well as in subgroups of the population.
The projected half-lives for overall graft survival in recipients by donor risk grade were I (10.7 years), II (10.0 years), III (7.9 years), IV (5.7 years) and V (4.5 years). This study indicates that there is great variability in the quality of deceased donor kidneys and that the assessment of risk might be enhanced by this scoring system as compared to the simple two-tiered system of the current ECD classification. 相似文献
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Noninvasive Intracranial Cerebral Flow Velocity Evaluation in the Emergency Department by Emergency Physicians 总被引:2,自引:0,他引:2
Michael Shafé MD Michael Blaivas MD RDMS Edmond Hooker MD Leigh Straus BS 《Academic emergency medicine》2004,11(7):774-777
Transcranial Doppler (TCD) is an accepted modality for the evaluation of cerebral blood flow velocities. OBJECTIVES: The purpose of this study was to test the feasibility of bedside TCD measurement in the emergency department (ED) with critically ill, intubated patients. METHODS: A prospective convenience sample of patients presenting to a university hospital over a two-month period underwent TCD evaluation of the middle cerebral artery. Intubated patients with head trauma and any patient requiring tracheal intubation were eligible. A 2-MHz Doppler probe was positioned over the temporal bone to acquire blood flow velocities. An emergency medicine resident and research assistant obtained measurements. Continuous TCD tracings were recorded on a video cassette recorder tape for quality assurance review and data collection. Vital signs and therapeutic interventions were also recorded. Flow velocities were measured in cm/s; the peak Resistance Index (RI) was calculated for each patient. RESULTS: A total of 30 patients were enrolled in the study. Adequate tracings were obtained in 25 patients (83%) without a disruption of resuscitation. Tracings could not be obtained in five patients; they were listed as TCD failures. However, in two of these patients, adequate flow velocity tracings were obtained after resuscitation. Four patients were evaluated during tracheal intubation. One patient was monitored successfully during cardiopulmonary resuscitation. The median time required for data acquisition was 1.9 minutes. The mean highest RI for those who expired was 0.84. For those who survived, the mean highest RI was 0.52. The difference of 0.32 was statistically significant (p = 0.04). CONCLUSIONS: Noninvasive blood flow velocity monitoring of the middle cerebral artery using TCD is feasible in the ED when performed at the bedside on intubated patients with traumatic brain injury and others during tracheal intubation and resuscitation. 相似文献
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Roger S Chan Michael H Duong Aaron V Kaplan 《Catheterization and cardiovascular interventions》2007,70(3):374-378
Percutaneous intervention in saphenous vein grafts (SVG) carries a higher risk of distal embolization than intervention in a native vessel, and use of a distal protection device has been shown to improve the outcomes in SVG interventions. We describe an intervention done in an unexpected 'Y' SVG which required dual distal protection with Filterwires placed in both limbs of the diseased graft and which was performed via a 6 Fr guide catheter. 相似文献
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Robert P. Kusy BS MS PhD 《American journal of orthodontics and dentofacial orthopedics》2004,125(6):726-732
Using an earlier model, which described the critical contact angle for binding from second-order angulation alone, a more generalized model is derived that combines the effects of angulation and torque. From this vantage point, the onset of binding is evaluated for 3 scenarios: second-order angulation alone, third-order torque only, and a combination of second-order angulation and third-order torque. These scenarios are detailed by plotting the critical contact angle for binding against the torque angle as a function of 10 wire dimensions (16 x 16, 16 x 22, 17 x 17, 17 x 22, 17 x 25, 18 x 18, 18 x 22, 18 x 25, 19 x 25, and 21 x 25 mil), 4 bracket widths (70, 100, 130, and 160 mil), and 4 bracket slots (18, 20.5, 22, and 24.5 mil). From these plots, we learn that each wire base dimension (eg, an 18-mil base as found in 18 x 18-mil, 18 x 22-mil and 18 x 25-mil archwires) has a common maximum critical contact angle for binding. Moreover, each wire-slot combination has a common maximum torque angle, which is independent of bracket width. Finally, we learn that archwire-bracket combinations that use a metric 0.5-mm slot might have some advantages with regard to torquing--given the current philosophy that light, continuous forces are more favorable. 相似文献