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61.
应用生理性成骨力值概念治疗骨折与骨不连——兼论MO现象与有效固定 总被引:2,自引:2,他引:0
张春才 禹宝庆 许硕贵 苏佳灿 王家林 牛云飞 康庆林 付青格 任可 张鹏 高堂成 张雪松 严望军 王冠军 汪光晔 万岷 李波 孙建伟 王仁 丛永健 杨郁野 郑医红 李格当 刘欣伟 管华鹏 《中国骨伤》2007,20(6):361-363
治疗骨折与术后合并的骨不连,至今仍是骨创伤领域的难题之一。研究分析当前的学术思想,探索更接近骨愈合规律的理念与技术,是必然的学术趋势。1当前骨创伤理论与技术1.1AO从20世纪50年代起,AO组织提出解剖复位与骨块间坚强固定与加压的概念。50年间,由于伴随生物材料学的发展和内固定形式的进步,业已成为治疗骨折与骨不连的主要理论与方法,并取得了瞩目的成就,但同时也发现了存在并需继续探讨的若干问题。(1)偏心类的固定模式,如加压钢板,其疗效超越一般非加压性钢板。但同时也发现:①内固定期间,骨质萎缩,骨痂纹理凌乱或难觅骨痂;②钢板… 相似文献
62.
A tumor-targeted and conditionally replicating oncolytic adenovirus vector expressing TRAIL for treatment of liver metastases. 总被引:3,自引:0,他引:3
Pavel Sova Xiao-Wei Ren Shaoheng Ni Kathrin M Bernt Jie Mi Nancy Kiviat André Lieber 《Molecular therapy》2004,9(4):496-509
We have constructed a new capsid-modified adenovirus (Ad) vector that specifically replicates in tumor cells and expresses TNF-related apoptosis-inducing ligand (TRAIL). The Ad capsid contains short-shafted fibers derived from Ad serotype 35, which allow for efficient infection of malignant tumor cells, and largely avoids innate toxicity after intravenous application. Replication-dependent homologous recombination in Ad genomes was used to achieve tumor-specific expression of Ad E1a (to mediate viral replication) and TRAIL (to mediate apoptosis and enhance release of progeny virus from infected cells). We demonstrated that our oncolytic vector (Ad5/35.IR-E1A/TRAIL) induced apoptosis in human tumor cell lines derived from colorectal, lung, prostate, and liver cancer. Both in vitro and in vivo tumor models showed efficient intratumoral spread of this vector. In a model for metastatic colon cancer, tail vein infusion of Ad5/35.IR-E1A/TRAIL resulted in elimination of preestablished liver metastases. Intravenous injection of this vector caused a transient elevation of serum glutamic pyruvic transaminase in tumor-bearing mice, which we attributed to factors released from apoptotic tumor cells. Liver histology analyzed at day 14 after virus injection did not show signs of hepatocellular damage. This new oncolytic vector represents a potentially efficient means for gene therapy of metastatic cancer. 相似文献
63.
Defective implant osseointegration under protein undernutrition: prevention by PTH or pamidronate. 总被引:1,自引:0,他引:1
Romain Dayer Isabelle Badoud René Rizzoli Patrick Ammann 《Journal of bone and mineral research》2007,22(10):1526-1533
Protein deficiency is associated with impaired titanium osseointegration. We studied whether systemic treatment with PTH or pamidronate could influence the resistance to pull-out of titanium rods implanted into rats proximal tibia under normal and isocaloric low protein intake. PTH or pamidronate prevented the deleterious effects of protein undernutrition on bone microarchitecture close to the implant and on mechanical fixation. PTH even significantly improved implant osseointegration. INTRODUCTION: Protein deficiency is highly prevalent among elderly patients hospitalized in orthopedic wards. Reduced protein intake impairs titanium osseointegration in rats. Whether stimulator of bone formation or inhibitor of bone resorption could improve implant osseointegration under protein deprivation is not known. We studied the effects of systemic treatment with PTH or pamidronate on the resistance to pull-out of titanium rods implanted into rats proximal tibia under normal and isocaloric low protein intake. MATERIALS AND METHODS: We measured the resistance to pull-out 1-mm-diameter titanium rods implanted into the proximal tibias of 49 adult female rats receiving a normal or an isocaloric low protein diet. After 2 wk on either diet, the implants were inserted, and the rats received PTH(1-34), pamidronate or saline vehicle for 8 wk. The tibias were removed for microCT morphometry, followed by the evaluation of pull-out strength. RESULTS: Pull-out strength was lower in rats fed an isocaloric low protein diet compared with rats fed a normal protein intake (-29%). PTH and pamidronate significantly increased pull-out strength in animals fed a normal or a low protein diet, the effect of PTH being of higher magnitude. The PTH- or pamidronate-mediated increase in pull-out strength was associated with significant increases of relative bone volume, bone-to-implant contact, and trabecular thickness, whereas trabecular spacing was reduced, in the vicinity of the implants. CONCLUSIONS: We confirmed that isocaloric low protein intake impairs titanium implant osseointegration. PTH or pamidronate prevented the deleterious effects of protein undernutrition and even significantly improved the implant osseointegration. These results indicate that systemic administration of PTH or pamidronate could be considered for preventing uncemented arthroplasty loosening in protein undernourished patients. 相似文献
64.
65.
Jacobo E Mintzer Larry E Tune Christopher D Breder René Swanink Ronald N Marcus Robert D McQuade Andy Forbes 《The American journal of geriatric psychiatry》2007,15(11):918-931
OBJECTIVE: To assess the efficacy and safety of aripiprazole for psychosis associated with Alzheimer dementia (AD). METHODS: In this double-blind, multicenter study, 487 institutionalized patients with psychosis associated with AD were randomized to placebo or aripiprazole, 2, 5 or 10 mg/day. Primary efficacy assessment was the mean change from baseline to week 10 on the Neuropsychiatric Inventory-Nursing Home (NPI-NH) version Psychosis Subscale score. Secondary measures included NPI-NH Total, Clinical Global Impression-Severity of Illness (CGI-S), Brief Psychiatric Rating Scale (BPRS) Core and Total, and the Cohen-Mansfield Agitation Inventory (CMAI) scores. RESULTS: Aripiprazole 10 mg/day showed significantly greater improvements (mean change [2 x SD]) than placebo on the NPI-NH Psychosis Subscale (-6.87 [8.6] versus -5.13 [10.0]; F = 6.29, df = 1, 422, p = 0.013 by analysis of covariance [ANCOVA]); CGI-S (-0.72 [1.8] versus -0.46 [1.6]; F = 4.68, df = 1, 419, p = 0.031 [ANCOVA]); BPRS Total (-7.12 [18.4] versus -4.17 [21.6]; F = 4.72, df = 1, 399, p = 0.030 [ANCOVA]); BPRS Core (-3.07 [6.9] versus -1.74 [7.8]; F = 7.30, df = 1, 407, p = 0.007 [ANCOVA]); CMAI (-10.96 [22.6] versus -6.64 [28.6]; F = 5.23, df = 1, 410, p = 0.023 [ANCOVA]), and NPI-NH Psychosis response rate (65 versus 50%; chi(2) = 5.52, df = 1, p = 0.019 [CMH]). Aripiprazole 5 mg/day showed significant improvements versus placebo on BPRS and CMAI scores. Aripiprazole 2 mg/day was not efficacious. Cerebrovascular adverse events were reported: aripiprazole 2 mg/day, N = 1; 5 mg/day, N = 2; 10 mg/day, N = 4; placebo, N = 0. No deaths in any group (aripiprazole 2 mg/day, 3%; 5 mg/day, 2%; 10 mg/day, 7%; placebo, 3%) were considered to be treatment-related. CONCLUSION: Aripiprazole 10 mg/day was efficacious and safe for psychosis associated with AD, significantly improving psychotic symptoms, agitation, and clinical global impression. However, clinicians should be aware of the safety considerations of atypical antipsychotic uses in this population. 相似文献
66.
骨髓间充质干细胞向肝细胞的横向分化 总被引:1,自引:0,他引:1
目的:综合分析骨髓间充质干细胞向肝细胞分化的研究现状及应用前景。资料来源:应用计算机检索Pubmed 2000—01/2005—04有关干细胞及其向肝细胞横向分化方面的文献,检索词“stem cell,hepatoeyte.transdifferentiation”,并限定文章种类为English。资料选择:对检索到的有关干细胞及其向肝细胞横向分化方面的文献进行整理,选取针对性强的文章。同一领域的文献则选择近期发表或权威杂志的文章。资料提炼:共检索到45篇相关文献,其中38篇符合要求,7篇为重复同一研究而排除。资料综合:利用骨髓间充质干细胞在肝损伤等病理状态下具有分化为肝细胞的特性,实现肝组织重建,纠正肝细胞代谢和合成功能障碍,为治疗肝炎、肝硬化、肝癌及肝代谢性疾病提供了新的策略。干细胞在肝病治疗中的应用无疑是对传统治疗方式的挑战。结论:多数学者的研究表明,干细胞具有分化为肝细胞及胆管细胞样细胞的潜能,但也有少数学者持否定意见。目前对于移植后干细胞是产生细胞融合还是分化作用尚存在争议。 相似文献
67.
目的:探讨抗人热休克蛋白60或抗分枝杆菌热休克蛋白65抗体是否能够预测因急性心源性胸痛入院的患者一年预后不良。设计:前瞻性观察研究。地点:教学医院。患者:连续588例急诊收治的疑似急性心源性胸痛患者。主要观察指标:测定入院后晨起血样的抗人热休克蛋白60和抗分枝杆菌热休克蛋白65效价。出院后终点为冠心病死亡、非致死性心肌梗死、冠状动脉搭桥术、经皮穿刺腔内冠状动脉成形术、血管造影或因心脏缺血性胸痛加重再次入院。 相似文献
68.
69.
目的 探讨常年性变应性鼻炎 (PAR)患者细胞免疫功能状态及微波凝固治疗的作用机制。方法 观察组 2 5例PAR患者分别于微波治疗前以及治疗 1个月后应用免疫组化法检测鼻粘膜上皮和外周血CD3、CD4、CD8、CD4/CD8水平。健康对照组 1 5例亦作相应检测。结果 PAR患者治疗前鼻粘膜及外周血CD3、CD4明显高于正常人 ,CD8低于正常人 ,CD4/CD8比值升高 ,与正常人比较差异有显著性 (P <0 .0 5)。微波治疗后CD4明显减少 ,CD8升高 ,CD4/CD8接近于健康对照组。结论 PAR患者存在明显的细胞免疫功能障碍 ;微波局部凝固治疗可改善PAR患者的细胞免疫状况。 相似文献
70.