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81.
Abhay Vats Kristen Gillingham Arthur Matas Blanche Chavers 《American journal of transplantation》2002,2(10):939-945
We evaluated variables associated with improved late graft survival in 290 children transplanted between 11/1/1984 and 12/31/1997, and who had > 1 year graft survival. We studied the following variables: age, gender, race, primary disease (diseases prone to recurrence, i.e. hemolytic uremic syndrome, focal segmental glomerulosclerosis or oxalosis vs. others), primary vs. retransplant; donor source, acute tubular necrosis, acute rejection episodes in the first year, transplant era and discharge serum creatinine. Graft half-life was defined as the time taken for 1/2 of the grafts functioning at 1 year to fail. There were 205 living donor and 85 cadaveric transplant. The cumulative graft survival at 5 and 10 years was 88% and 75% for living donor, and 72% and 46% for cadaveric, respectively. Multivariate analyses showed a higher late graft survival to be associated with: no acute rejection episodes (risk ratio 0.16, p = 0.0001), age 2-5 years (risk ratio 0.24, p = 0.0007), living donor (risk ratio 0.46, p = 0.017), primary nonrecurrent disease (risk ratio 0.29, p = 0.001), Caucasian race (risk ratio 0.40, p = 0.006). A high half-life was seen with living donor transplant (21.3 years) and the age group 2-5 years (27.5 years). Further, living donor patients with no acute rejection episodes had the best half-life of 37.6 years, while children with hemolytic uremic syndrome, focal segmental glomerulosclerosis or oxalosis had the lowest overall half-life of 5.6 years. This study finds that living donor, no acute rejection episodes, age 2-5 years, Caucasian race and having a disease not prone to recurrence are strong predictors of late graft survival. Hence, preferential use of living donor and prevention of acute rejection episodes in the first year are key variables that can improve long-term renal graft survival in children. 相似文献
82.
H. P. MERCER P. C. ROPER J. F. O'DUFFY G. J. NESS 《Journal of paediatrics and child health》1994,30(2):134-139
The survival of low birthweight infants £2000g born in the central Queensland area during the years 1979 to 1991 was examined. Five hundred and sixty such infants were either delivered at one of the two Rockhampton obstetric units (Rockhampton Base Hospital and the Mater Misericordiae Hospital) or retrieved from outlying central Queensland areas. Both hospitals had intensive care nurseries capable of ventilation and infants were transferred to tertiary centres only for cardiac or surgical treatment. The study involved all liveborn infants', including those with lethal malformations and all deaths up to the time of discharge. Survival rates were as follows: £500 g 0%, 501 £750 g 30%, 751 £1000 g 51%, 1001 ± 1500 g 79%, 1501 £2000g 93%. The survival of Aboriginal infants and outborn infants were found to be essentially the same as the overall group. 相似文献
83.
麦胚提取物对辐射损伤修复的实验研究 总被引:2,自引:1,他引:1
目的 研究麦胚提取物对小鼠辐射损伤修复的调节和保护作用。方法 采用辐射前或辐射同时饲喂一定量的麦胚提取物,观察小鼠经X射线一次性全身照射后的临床症状、30d存活率、骨髓微核率、外周血白细胞总数在不同时间的变化。结果 与对照组(单纯照射)比较,饲喂麦胚提取物可使小鼠的头面部皮肤、小肠黏膜、肾脏损伤症状得到明显改善;30d存活率为86.17%(P<0.01),提高存活率41.79%,保护系数为1.72;骨髓微核率4.62‰;比对照组(12.14‰)降低(P<0.01);外周血白细胞总数在7,13,20,30d均显回升(P<0.05,P<0.01,P<0.01,P<0.01)。结论 麦胚提取物对小鼠辐射损伤修复有一定程度的调节和保护作用,对于辅助肿瘤放射治疗具有重要意义。 相似文献
84.
J. J. HOORWEG J. A. RAUWERDA G. A. CROLL A. J. C. MACKAAY E. K. J. RISSE N. DE VRIES R. M. TIWARI 《Clinical otolaryngology》1994,19(6):496-501
The records of 28 patients who underwent free jejunal graft reconstruction after resection for cancer involving the pharynx were analysed. Seven patients had a T3 carcinoma, 15 patients T4 and six patients recurrence after laryngectomy. Ten patients had received radiotherapy in the past. Post-operatively, 15 patients (54%) had complications and two patients (7%) died. No significant difference was observed in the complication rate between the group that received radiotherapy in the past and those who did not. Nineteen patients received post-operative radiotherapy. Nine patients had no radiotherapy on the basis of complete resection or because of serious complications. For the whole group the 2-year recurrence free period and survival were 42% and 51% respectively. The postoperative radiotherapy group had a significantly better survival (73%) and recurrence free period (63%) than the group without post-operative radiotherapy (0%). Thus, post-operative radiotherapy seems indicated irrespective of resection margins. 相似文献
85.
86.
Scott L. Nyberg Arthur J. Matas Walter K. Kremers Jeffrey D. Thostenson Timothy S. Larson Mikel Prieto Michael B. Ishitani Sylvester Sterioff Mark D. Stegall 《American journal of transplantation》2003,3(6):715-721
We previously proposed a quantitative approach to assess donor organs for cadaver renal transplantation. To improve on our original scoring system, we studied 34 324 patients who received cadaver renal transplants from adult donors between 1994 and 1999 and were reported to the UNOS Scientific Renal Transplant Registry. A scoring system was developed from five donor variables (age, 0-25 points; history of hypertension, 0-4; creatinine clearance before procurement, 0-4; cause of death, 0-3; HLA mismatch, 0-3) that showed a significant correlation with renal function and long-term graft survival. Cadaver kidneys were stratified by cumulative donor score: grade A, 0-9 points; grade B, 10-19; grade C, 20-29; and grade D, 30-39. The influence of donor score on renal function and graft survival was most severe above 20 points, designated 'marginal' kidneys. In summary, a donor scoring system developed from a large population database was useful in predicting outcome after cadaver renal transplantation. The improved system provides a quantitative approach to evaluation of marginal kidneys and may improve allocation of these organs in cadaver renal transplantation. 相似文献
87.
本文研究了~(60)Co-γ射线照射后HeLa细胞的存活曲线,比较了两种数学模式拟合的结果.拟合优度以对误差加权的残差平方和(Q)作为统计指标进行评价.结果表明模式的拟合度较模式为优. 相似文献
88.
Recent studies of mortality from motor neurone disease (MND) in Sweden have demonstrated rising levels of mortality from the disease, especially amongst older age groups. Case-control investigations have suggested that certain environmental factors are significantly related to variations in mortality from the disease, and are associated with a probable individual susceptibility to MND. This study applies an innovative epidemiological technique to longitudinal and cohort analysis of Swedish mortality from MND during the period 1961 to 1990. Survival modelling shows that a subpopulation susceptible to MND exists in Sweden, as has been demonstrated in other countries. The increased life expectancy of the Swedish population since 1961 has resulted in more of that susceptible population living to the ages at which MND is expressed, explaining the majority of the increase in mortality from the disease. However, environmental factors may play a role in accelerating the course of MND and may affect the timing of death within the susceptible sub-population. 相似文献
89.
Levin Adeera; Djurdjev Ognjenka; Duncan John; Rosenbaum Debbie; Werb Ron 《Nephrology, dialysis, transplantation》2006,21(2):370-377
Haemoglobin (Hgb) levels are known to be associated with numerousadverse outcomes in both chronic kidney disease (CKD) and non-CKDpatients. This analysis evaluates the association of baseline haemoglobinlevels on survival in CKD patients, who are followed by nephrologists,irrespective of glomerular filtration rate (GFR), prior to initiationof renal replacement therapy (RRT) and erythropoietin hormonereplacement therapy. Analysis of data from the provincial database (PROMIS, PatientRegistration and Outcome Management Information System) in BritishColumbia, Canada, was undertaken. Records used for the analysisincluded all CKD patients at first registration: GFR <60ml/min/1.73 m2, not yet on dialysis, starting from May 1998to October 2002, and who had complete data (defined as age andgender, diabetic status, eGFR and Hgb levels). The primary objective of this study was to determine the associationof Hgb and survival controlling for eGFR at first registrationvalue, age, gender and diabetic status. Multivariate Cox proportionalhazards analysis with time to death as outcome variable wasperformed. The cohort included 3028 patients: the mean age was 65 years,28% were diabetic, and the mean eGFR in the cohort was 21 ml/min/1.73m2. The cohort is representative of the BC CKD and dialysispopulation regarding ethnicity: 64% Caucasian, 32% Asian. Medianfollow-up was 27 months, 1 year survival was 0.92, 2 year survivalwas 0.85. Hgb at initial registration is a statistically independentpredictor of survival (RR = 0.875 for every 10 g/l, 95% CI:0.8350.917, P = 0.0001), after adjusting for age, gender,diabetic status and baseline eGFR. Further analysis, controllingfor RRT, demonstrated a similar association between Hgb andsurvival (RR = 0.853 for every 10 g/l, 95% CI: 0.7990.910,P = 0.0001), after adjusting for above variables. Substantialvariation in Hgb values exists at all GFR levels. These findings underscore the importance of evaluating Hgb atall GFR levels, and the need to study the impact of modificationof Hgb at different GFR levels on survival. 相似文献
90.
Thick malignant melanomas in general tend to have a poor prognosis, but exceptions occur where there may be no further recurrence. The reasons for this difference in clinical behaviour are not fully understood. We have looked at thick malignant melanomas (greater than 3.0 mm) in the East of Scotland that have no evidence of metastasis after a minimum of 6 years follow-up and compared the clinical and histological features with a similar group, associated with histological evidence of metastasis and/or death. Both groups received similar treatment regimes. We have identified 41 patients with thick melanomas in the former group. When compared with the control group, factors found to be significantly different between the two groups were: the nature of the lower margin of the tumour; vascular invasion; and anatomical location. 相似文献