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91.
同种异体骨支撑架微创治疗股骨头坏死的临床研究 总被引:1,自引:0,他引:1
目的应用改良髓芯减压术结合同种异体骨支撑架加自体骨和脱钙骨基质(decalcified bone matrix,DBM)治疗早期股骨头坏死,探索早期股骨头坏死的微创治疗方法。方法2004年1月~2005年4月,23例24个髋关节采用经大转子下通过股骨颈钻隧道至股骨头骨坏死区,将装有自体松质骨和DBM的同种异体骨支撑架经隧道拧入骨坏死区直至软骨下骨约5mm处,隧道远端用自体髂骨填塞。观察手术前后Harris评分变化、x线影像学表现及是否需进一步治疗。结果本组所有患者均获得随访,平均随访19(12—27)个月,以最后一次随访资料作为最终评价依据。Harris评分,术前优良率为43.5%(10/23)。术后优良率为91.3%(21/23)。22侧髋关节影像学表现保持稳定,无明显并发症发生。结论同种异体骨支撑架植入结合自体松质骨和DBM治疗成人股骨头坏死,增加了股骨头负重区软骨下骨的机械支撑,成骨作用强,有利于股骨头坏死的修复与重建,同时,不破坏患者股骨头本身的血液供应,创伤小,操作简单,值得临床推广使用。 相似文献
92.
Javairiah Fatima Scott G. Houghton Michael G. Sarr 《Journal of gastrointestinal surgery》2007,11(8):1052-1056
Small bowel transplantation (SBT) is associated with poorly understood enteric dysfunction. The study of SBT in mice is hindered
by the technical difficulty of orthotopic SBT in the mouse. Our aim was to develop an easy preparation of extrinsic denervation
of the entire jejunoileum in mice as a model of orthotopic SBT. All neurolymphatic tissues accompanying the superior mesenteric
artery (SMA) and vein (SMV) were ligated just distal to the middle colic vessels. The SMA and SMV were then stripped of investing
adventitia, and the mesentery to jejunum and colon were transected radially. Jejunum and colon were not transected and reanastomosed.
To confirm extrinsic denervation 1, 3, and 6 months later, segments of small bowel were stained for protein gene product 9.5
(PGP9.5) and tyrosine hydroxylase (TH). Tyrosine hydroxylase immunoreactive intensity was then quantified using a semiquantitative
analysis. Immunohistochemical fluorescence showed persistence of PGP9.5 immunoreactivity confirming enteric nerves in jejunoileum;
however, there was no TH immunoreactivity in jejunoileum in denervated mice despite the expected preservation of TH immunoreactivity
in the still-innervated duodenum at 1 month. At 3 months, sparse immunoreactivity for TH was present, and by 6 months, reinnervation
of TH-containing nerves appeared similar to controls. Quantification of intensity at each time-point further confirmed this
trend. This technique in the mouse accomplishes a complete extrinsic denervation of jejunoileum early postoperatively (1 and
3 months); reinnervation occurs by 6 months. This is an easily learned murine model of orthotopic SBT.
Presented at the American Gastroenterological Association during Digestive Disease Week in Los Angeles, CA, as a poster presentation
on May 23 2006. Abstract published in GastroenterologyE 2006; 130:A604. 相似文献
93.
Neurologic complications are common after transplantation and affect 30-60% of transplant recipients. The etiology of most of the posttransplant neurologic disorders is related to the opportunistic infections, both systemic and involving central nervous system (CNS), toxicity of immunosuppressive medications, and the metabolic insult created by the underlying primary disease and the transplant procedure. Neuroimaging studies are one of the key tools in the evaluation and enable early diagnosis of neurologic complications in transplant patients, especially posterior reversible leukoencephalopathy syndrome, central pontine myelinolysis, intracerebral hemorrhage, and fungal and bacterial abscesses. Magnetic resonance imaging (MRI) is the preferred technique, but each of the available neuroimaging techniques offers a unique insight into the pathophysiologic mechanisms underlying neurologic complications of transplantation. The role of neuroimaging in this population includes early detection of calcineurin inhibitor neurotoxicity, opportunistic infections, neoplasia, metabolic disorders, or cerebrovascular diseases. In addition, we can monitor longitudinal progression of disease and treatment response. 相似文献
94.
G. S. Sayuk T. L. Leet M. A. Schnitzler P. H. Hayashi 《American journal of transplantation》2007,7(1):151-160
Deceased donor factors associated with poor graft outcome are well known, but how often these factors lead to livers left untransplanted is poorly defined. A nested, case-control study was conducted using the United Network for Organ Sharing (UNOS) database from 1987 to 2005. Only those donating >/=1 solid organ were included. Primary outcome was livers not transplanted (LNT, cases) versus transplanted (LT, controls). Primary variables for multivariate analysis were donor age and obesity. Covariates included donation after cardiac death (DCD), cerebral vascular accident death, viral serologies, cancer, ALT and bilirubin. There were 23 373 (26%) LNT's from 91 362 donors who donated at least one organ. Percent LNT fell over time (1987-1990: 48%; 1991-1995: 29%; 1996-2000: 21%; 2000-2005: 16%; p < 0.01). Increased age (odds ratio: 4.2, 95% confidence interval 3.6-4.9, p < 0.01) and obesity (2.1, 1.9-2.3, p < 0.01) were significantly associated with LNT across all time periods. Other significant factors included DCD and elevated ALT. For 2001-2005, population attributable risk indicate that age >40, abnormal ALT and obesity account for 32.6%, 25.3% and 9.2% of untransplanted livers, respectively. Use of expanded criteria livers has pushed LNT lower in spite of an aging and heavier donor population. Nevertheless, age and obesity still account for a significant portion of untransplanted livers. 相似文献
95.
Michael Robson Isabelle Côte Ian Abbs Geoffrey Koffman David Goldsmith 《American journal of transplantation》2003,3(3):324-327
Thrombotic microangiopathy is a rare but important finding in the context of organ transplantation. Acute renal insufficiency in the setting of hemolysis and thrombocytopenia, a triad that constitutes 'hemolytic uremic syndrome', can be associated with, or triggered by, conditions such as verocytotoxin-producing Escherichia coli, viral infections, malignant hypertension, scleroderma, allograft rejection, lupus erythematosus, pregnancy, and medications including mitomycin C, calcineurin inhibitors, and oral contraceptives. After renal transplantation, it can occur, as either a de novo episode, or recurrent disease. Calcineurin inhibitors have long been associated with post-transplantation thrombotic microangiopathy. Sirolimus has been used as a primary immunosuppressant in patients transplanted with a history of earlier hemolytic-uremic syndrome, and also as rescue therapy in patients with calcineurin-inhibitor-associated thrombotic microangiopathy. We describe four cases where there was significant thrombotic microangiopathy in the context of contemporaneous or contiguous calcineurin inhibitor and sirolimus usage. As the intrarenal cyclosporin concentration is thought to be significantly elevated when cyclosporin and sirolimus are used together, this may explain these findings, and mandates caution in their co-administration. 相似文献
96.
97.
肝移植术后并发胆道狭窄和胆泥淤积影像诊断及介入治疗 总被引:1,自引:0,他引:1
目的:评价肝移植术后胆道狭窄和胆泥淤积影像诊断及介入治疗的价值。方法:对39例肝移植术后并发胆道狭窄和胆泥淤积的影像诊断及介入治疗进行回顾性分析。结果:超声、T型管胆道造影、CT和MRI检查诊断胆道狭窄伴胆泥形成39例,38例介入治疗后胆道梗阻症状明显缓解;1例介入治疗后胆道梗阻症状未明显改善,后行外科胆管修补术。结论:T型管胆道造影或直接经皮胆道造影对肝移植术后胆道狭窄和胆泥淤积诊断特异性及敏感性最高,放射介入和内镜介入技术对其均发挥重要的治疗作用。 相似文献
98.
99.
肝移植术后缺血型胆道病变的介入治疗进展 总被引:1,自引:0,他引:1
肝移植是终末期肝病最有希望的治疗方法之一。移植肝缺血型胆道病变逐渐成为肝移植术后胆道并发症的主要类型,其病因及发病机制复杂,临床处理棘手,日益成为影响肝移植患者长期成活及导致移植物丢失的主要原因之一。国内外尝试用多种方法来预防和治疗缺血型胆道病变,介入治疗被认为是首选治疗方法,疗效显著。 相似文献
100.
Tacrolimus Exposure and Evolution of Renal Allograft Histology in the First Year After Transplantation 总被引:1,自引:1,他引:0
M. Naesens E. Lerut B. V. Damme Y. Vanrenterghem D. R. J. Kuypers 《American journal of transplantation》2007,7(9):2114-2123
Tacrolimus has a narrow therapeutic window and is characterized by a large inter-individual variability in bioavailability. The impact of tacrolimus exposure on subclinical evolution of graft histology has not been studied in renal recipients. This analysis included 239 protocol biopsies (obtained at implantation, 3 and 12 months) of 120 consecutive kidney recipients treated with tacrolimus, mycophenolate mofetil (MMF) and corticosteroids. Biopsies were scored according to the Banff 2001 criteria and a chronicity score was calculated. Prospective pharmacokinetic data were included in the analysis (5544 tacrolimus predose blood concentrations and tacrolimus AUC(0-12) at 3 and 12 months). Higher donor age and higher number of human leukocyte antigen-DR (HLA-DR) mismatches were independent predictors of subclinical acute rejection at 3 months, present in 8.7% of patients. The number of HLA-DR mismatches was independently associated with biopsy-proven clinical acute rejection. Biopsy-proven acute rejection episodes and low mean tacrolimus exposure were independently associated with higher increase in chronicity scores between 3 and 12 months after transplantation. This observational study suggests that rejection phenomena and immune-mediated mechanisms remain important in the early progression of chronic allograft pathology. Tacrolimus doses or systemic exposure were not associated with lesions of calcineurin inhibitor nephrotoxicity, suggesting that other factors determine susceptibility to tacrolimus nephrotoxicity. 相似文献