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21.
关节镜下应用“微骨折”方法修复关节软骨缺损 总被引:3,自引:3,他引:0
目的:探讨关节镜下应用“微骨折”技术对膝关节全层关节软骨缺损修复的效果。方法:对68例全层关节软骨缺损患者进行随机分组:实验组(35例),男17例,女18例,平均年龄35.1岁,采用关节清理后应用“微骨折”技术进行处理,即利用骨刀设计的特性和适度的锤击力量造成软骨下的骨组织微小骨折,刺激软骨生长。对照组(33例),男17例,女16例,平均年龄31.6岁,仅作关节清理术。结果:术后随访6~18个月,平均8.6个月,按Lysholm评分标准,实验组明显优于对照组(P<0.01)。结论:关节镜下应用“微骨折”技术能够显著减轻关节疼痛,增加关节活动度,改善关节功能,是一种简单有效的修复全层关节软骨缺损方法。 相似文献
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RNA干扰及其在胶质瘤基因治疗中的应用 总被引:1,自引:0,他引:1
RNA干扰(RNA interference。RNAi)是双链RNA(double—stranded RNA,dsRNA)降解特异性靶基因转录出的mRNA。从而抑制靶蛋白表达的现象。自从二十世纪九十年代发现RNAi这一现象以来,RNAi已被广泛应用于研究基因功能、信号转导通路和基因治疗等方面。随着分子生物学、分子遗传学等学科的发展.发现了许多与肿瘤发生、发展和预后密切相关的基因。经过大量临床前期试验表明,针对特异性靶基因的小干扰RNA(short/small interfering RNA.siRNA)治疗胶质瘤是行之有效的。为基因治疗胶质瘤提供了新的思路。[第一段] 相似文献
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L. F. Trevillian A.-L. Ponsonby† T. Dwyer† L. L.-Y. Lim A. Kemp§ J. Cochrane† A. Carmichael‡ 《Clinical and experimental allergy》2003,33(4):483-489
BACKGROUND: Higher house dust mite (HDM) allergen exposure during infancy has been associated with increased HDM sensitization. Infant bedding has been associated with the accumulation of varying levels of HDM. Prospective data on the relationship between infant bedding and the development of HDM sensitization has not been previously examined. OBJECTIVES: To determine if particular types of bedding used in infancy are associated with increased risk of house dust mite sensitization in childhood. METHODS: A population-based sample (n = 498) of children born in 1988 or 1989, and who were resident in Northern Tasmania in 1997, participated in this study. These children were part of a birth cohort study (1988-95), the Tasmanian Infant Health Survey. Data on infant underbedding and mattresses was available on 460 and 457 children, respectively. The main outcome measure was HDM sensitization defined as a skin prick test (SPT) reaction of 3 mm or more to the allergens of Dermatophagoides pteronyssinus and/or Dermatophagoides farinae. RESULTS: The use of either sheepskin underbedding or plastic mattress covers in infancy was associated with an increased risk of sensitization to HDM allergens at age 8 years. The adjusted risk ratio (RR) for sensitization to HDM with sheepskin in infancy was 2.27 (95% CI: 1.14, 4.55), P = 0.020. The adjusted RR for sensitization to HDM with the use of plastic mattress covers in infancy was 2.06 (95% CI: 1.22, 3.51), P = 0.007. The use of a foam mattress in infancy was not related to subsequent HDM sensitization. CONCLUSION: Infant's bedding plays a role in the development of HDM sensitization in childhood. Intervention studies to examine mite allergen levels and the role of underbedding on the development of HDM sensitization are required. 相似文献
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载脂蛋白E基因多态性与脑梗死的相关性分析 总被引:12,自引:0,他引:12
目的 探讨载脂蛋白 E基因多态性与脑梗死的关系。方法 通过聚合酶链反应 -限制性片段长度多态性 (PCR- RFL P)分析结合 DNA直接银染技术检测 6 6例脑梗死 (CI)患者的载脂蛋白 E(Apo E)基因型 (其中家系中有明确脑梗死先证者的家族聚集性脑梗死 (FMACI)亚组 2 6例 ,家系中无脑卒中史的非家族聚集性脑梗死 (NF-MACI)亚组 4 0例 ) ,并与 90例健康对照组比较 ,同时检测血脂、脂蛋白 (a) [L P(a) ]及部分载脂蛋白。结果 脑梗死组ε3/4基因型频率明显高于对照组 (P<0 .0 1) ,ε3/3基因型频率明显低于对照组 (P<0 .0 1) ;两脑梗死亚组之间的ε3/4/ε3/3基因型频率虽有上升 /下降趋势 ,但未发现明显的统计学差异 ;FMACI组高密度脂蛋白 (HDL )水平明显低于 NFMACI组 (P<0 .0 5 )。结论 Apo E基因多态性与脑梗死的发生有关 ,ε4等位基因是脑梗死的易感因子 ,ε3等位基因对脑梗死的发生有保护作用 ;Apo E基因多态性和 HDL水平双重作用于家族聚集性脑梗死的发生。 相似文献
26.
Lisa M. Lim Anup Patel Thomas P. Ryan Patricia L. Stranahan Gerhard J. Fuchs 《Urology》1997,49(6):851-856
Objectives. To evaluate the process of soft-tissue electrovaporization and to study variables that affect tissue clearance rates in a laboratory setting, in order to identify parameters that can optimize transurethral electrovaporization of the prostate.Methods. Fresh bovine skeletal muscle, equivalent in impedance and surface properties to the human prostate, was submerged in 3.3% sorbitol solution and electrovaporized with a grooved monopolar electrode attached to the weighted arm of a linear actuator. The effects of excursion rate, applied mechanical load, power setting, electrode configuration, and generator performance on the volume of tissue removed, were assessed.Results. Tissue removal increased significantly when electrode excursion rate was slowed from 25 to 15 mm/s (P <0.05) and then to 10 mm/s (P <0.05); when the load was increased from 20 to 50 g (P <0.005); and when dial power was increased from 120 to 150 W (P <0.01). Tissue removal was generator dependent. There was no significant difference between the Force 40 and the Force 2 (P > 0.4), but a new computer-controlled constant power output generator (Force FX) did significantly improve tissue vaporization at an equivalent power setting (P <0.005 and P <0.01, respectively). Tissue removal was also dependent upon electrode configuration, with the VaporTrode-Grooved Bar removing significantly more tissue than either an ungrooved roller bar of equivalent size or 2-mm smooth roller ball, respectively, both after a single pass (P <0.001 and P <0.05) and after five repeated passes (P <0.05 and P <0.005). The histologic depth of tissue thermal effect was less than 1 mm, but it was 38% greater for the VaporTrode-Grooved Bar (0.68 mm) than for the standard cutting loop (0.5 mm, P <0.01).Conclusions. Using a novel method to quantify tissue removal, we have demonstrated that electrode configuration, excursion rate, applied load, power setting, and generator performance are interdependent factors that influence the efficacy of the electrovaporization process in a fluid environment. 相似文献
27.
Consumers were surveyed to determine their attitudes toward four systems of health care delivery (home health care, hospitals, nursing homes, and outpatient clinics) along 10 attributes. The results are analyzed using multiple discriminant analysis. Implications for the formulation of marketing strategies are discussed. 相似文献
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