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991.
992.
C. Ballet G. Roussey-Kesler J.-T. Aubin S. Brouard M. Giral P. Miqueu S. Louis S. van der Werf J.-P. Soulillou 《American journal of transplantation》2006,6(11):2796-2801
Rare kidney allograft recipients enjoy unaltered graft function years after interruption of their immunosuppressive treatment. To assess the extent to which this state of 'operational tolerance' (TOL) is specific to the graft and not the result of a global immunodeficiency, we analyzed the response of such patients following influenza vaccination. Hemagglutination inhibition titers and frequency of IFNgamma-secreting T cells were measured before 1 and 3 months after vaccination. The proportion of healthy volunteers (HV) responding to vaccine was significantly higher than that of immunosuppressed (IS) patients. Three 'TOL' patients presented a humoral response similar to that of HV, whereas the two others had a poor response, like the IS recipients. Although the small number of patients does not allow for definitive conclusions to be made, these data suggest that the status of tolerance may be heterogeneous, with some patients with a global immunodeficiency and others with an adapted response to vaccination. 相似文献
993.
We have previously reported the time trends, design and interventions in randomised controlled trials (RCTs) in cystic fibrosis (CF) from 1961 through 1997 [Cheng K, Smyth RL, Motley J, O'Hea U, Ashby D, Randomised controlled trials in cystic fibrosis (1966-1997) categorized by time, design, and intervention. Pediatr Pulmonol 2000, 29:1-7.]. We maintain an ongoing register of all RCTs and controlled clinical trials (CCTs) in CF and have noted that in the five years since 1997 there has been a 48% increase in published trials. We aimed to assess whether this increase has been associated with an improvement in design quality. All RCTs and CCTs from 1961-2002 were assessed. Two epochs were then compared, 1961-1997 and 1998-2002. For each trial we recorded the design, participant numbers and the intervention studied. 261 trials in 1998-2002 were compared with 544 trials in 1961-1997. Comparing the two epochs a similar proportion of trials were parallel, double-blind and placebo controlled; also the median number of participants was similar. In the later epoch 25% of trials were multicentre, compared with 11% previously. Whilst this recent increase in clinical trials in CF is welcome, this has not been associated with improvements in quality. The trend for an increasing proportion of trials to be multicentre is encouraging. There are however, still deficiencies in the design of clinical trials in CF. 相似文献
994.
L. L. Morselli L. Manetti C. Cosci C. Sardella F. Bogazzi C. Faldini E. Martino M. Gasperi 《Journal of orthopaedics and traumatology》2006,7(4):169-175
Growth hormone (GH) is fundamental for the maintenance of bone mass and metabolism both during childhood and in adulthood.
This effect is due to a complex interaction between circulating GH and IGF-I produced peripherally. In vitro data and experimental
animal models have clarified many of the regulatory mechanisms underlying the characteristic skeletal changes occurring in
acromegaly. This review focuses on the effects of GH excess on bone metabolism and mass in acromegalic patients and, in particular,
on the influence of factors such as hypogonadism, gender, age and therapy on bone metabolism and arthropathy. 相似文献
995.
M. J. Englesbe S. J. Pelletier S. Kheterpal M. O'Reilly D. A. Campbell Jr. 《American journal of transplantation》2006,6(4):666-670
The severity of illness in transplant patients and the complexity of transplant operations results in significant postoperative morbidity and mortality. Remarkable efforts have been made by transplant physicians to study and improve organ allocation, graft and patient survival, immunosuppression and the long-term management of post-transplant complications. Less effort has been spent studying the actual transplant operation and systems of acute transplant care. The National Surgical Quality Improvement Program (NSQIP) has provided a standardized approach to quality improvement and has demonstrated significant potential for a reduction in postoperative morbidity and mortality in other surgical disciplines. Medical centers are under increasing pressure to measure surgical quality and the nexus of transplant surgical quality improvement should not lie in the hands of CMS or JACHO, but rather it should be created and developed within the transplant community. The time has come for a national transplant surgical quality improvement program based on the NSQIP infrastructure. Such a proactive approach toward quality improvement from the transplant community is an excellent investment for patients, providers and health care payers. 相似文献
996.
997.
Chan C. H. Y Ng E. H. Y Chan C. L W 《世界核心医学期刊文摘》2006,2(6):15-15
目的:评价东部身体-智力-精神(EBMS)群体干预对进行体外受精(IVF)的中国妇女焦虑缓解的作用。设计:随机对照研究。机构:三级辅助生殖机构。受试者:227例接受第1个IVF周期治疗的妇女。干预:干预组(n=69)接受4次EBMS群体咨询,而对照组(n=115)无任何干预。主要观察指标:状态-特质焦虑问卷。结果:与对照组相比,干预组在干预后状态焦虑平均分显著下降。每组移植同样数目的卵子,但干预组没有明显更高妊娠率的倾向。 相似文献
998.
Abstract: Data from the National Education Longitudinal Study were combined with census data at the zip code level to examine the impact of neighborhood racial and ethnic diversity and consolidated inequality, in addition to individual, family, and school factors, on the likelihood of dropping out of high school. Results indicate that while the effects for diversity and consolidated inequality did not support the stated hypotheses, main effects for family risk and prior academic achievement were significant and in the stated direction. Also, when controlling for individual, family, school, and neighborhood characteristics, African Americans were less likely than White students to drop out of school. Implications for contextual effects research and educational outcomes are discussed. 相似文献
999.
1000.