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1.
胫骨延长后骨痂直径与新生骨预后关系的临床分析   总被引:1,自引:0,他引:1  
目的探讨胫骨延长后骨痂直径与新生骨预后的关系.方法 1996年1月~2001年12月,对68例胫骨延长者测量达所需延长长度时的骨痂直径,计算骨痂直径率(callus diameter ratios,CDR);统计拆除外固定架后2~4周时新生骨发生骨折例数及畸形角度,比较骨折和成角畸形与CDR的关系.结果拆除外固定架前胫骨前屈角度5度以上畸形19例,其中11例发生骨折;拆除外固定架后胫骨出现5度以上畸形6例,其中2例骨折;其余43例胫骨延长骨痂正常愈合.计算CDR值:CDR值小于80% 23例,其中发生新生骨骨折13例,成角畸形5度以上者21例;CDR在81%~85%之间6例,成角畸形5度以上4例;CDR值超过86% 39例,无畸形或新生骨骨折.结论胫骨延长时CDR小于80%时,容易发生新生骨骨折和畸形;CDR大于85%时,无新生骨骨折和畸形发生;两组间具有统计学意义(P<0.05).CDR是判断骨痂能否正常愈合较为理想的检测指标.  相似文献   
2.
促渗剂对水合胼胝类脂热转变影响的差示扫描热分析研究   总被引:8,自引:0,他引:8  
从人胼胝组织提取出类脂经水合后代替人皮肤角质层用作差示扫描热分析研究促渗剂作用的简单模型。研究了1,8-桉油精,月桂氮酮和丙二醇等促渗剂对水合胼胝类脂热转变特征的影响。三种促渗剂均不同程度地降低水合胼胝类脂的热变温度,作用强弱依次为1,8-桉油精>月桂氮酮>丙二醇。丙二醇与1,8-桉油精或月桂氮酮混合应用时对热转变的影响具有协同作用。结果提示促渗剂可能改变脂质分子的排列和增加其流动性。同时,水的存在对脂质分子物理结构的形成具有重要作用。  相似文献   
3.
Fracture healing and callus formation have traditionally been evaluated by using X-ray radiography. Here we compared X-ray radiography and peripheral quantitative computed tomography (pQCT) in evaluating the healing callus of standardized tibial fractures in 141 female rats after a 4- or 8-week follow-up. The results were compared with the tensile (4-week) and compressive (8-week) failure load of the callus. The projectional size of callus, as defined from lateral ex vivo radiographs, correlated significantly with the pQCT-defined cross-sectional area (CSA) of mid-callus. This relationship was dependent on the pQCT attenuation threshold, being higher for the CSA of compact bone (r = 0.85, P < 0.0001) than for the total bone CSA (r = 0.68, P < 0.0001). Radiographically defined callus projectional area also correlated strongly with bone mineral content (BMC) (r = 0.84–0.86, P < 0.0001). The mean optical density of the callus analyzed from the radiographs had only a weak correlation with the pQCT-defined bone mineral density (BMD) of callus. A weak negative relationship was found between CSA and BMD. The optical density analyzed from lateral radiographs did not correlate with the tensile or compressive failure load of callus. Callus size, BMC, and BMD were associated with the compressive failure load, whereas both radiographs and pQCT were poor in explaining the failure load in tension. Received: 28 June 1999 / Accepted: 28 October 1999  相似文献   
4.
石斛愈伤组织培养物的药用前景探讨   总被引:21,自引:1,他引:21  
黄民权  卢应京 《中药材》1998,21(11):543-545
石解药材的自然资源严重枯竭。本研究从石斛重要药用有效成分多糖的角度出发,所作的愈伤组织培养物和它的原植物的比较,显示出石解愈伤组织培养物有可能代替原植物作药用,既解决石料药源紧缺,又带来保护环境生态和商业利益的理想途径。  相似文献   
5.
何首乌组织培养的研究   总被引:10,自引:0,他引:10  
杜勤  符红 《中药材》1998,21(3):109-110
采用单因子、正交设计法考察了基本培养基、激素以及光暗条件对何首乌幼嫩茎、叶诱导愈伤组织的影响,以及培养时间与愈伤组织生长量间的关系。实验研究表明:MS 2,4D1mg/L 6-BA1mg/L IBA0.5mg/L和暗培养对诱导何首乌愈伤组织产生效果较好;接种12天时愈伤组织生长量达到最大;愈伤组织经诱导能够产生完整植株,成苗率为95%。  相似文献   
6.
After bone trauma, the natural response to restore bone function is the formation of a callus around the fracture. Although several bone healing models have been developed, none have effectively perceived early callus formation and shape as the result of an optimal response to a mechanobiological stimulus.In this paper, we investigate which stimulus regulates early callus formation. An optimal design problem is formulated, and several objective functions are defined, each using a different mechanobiological stimulus. The following stimuli were analysed: the interfragmentary strain, the second invariant of the deviatoric strain tensor and a generic inflammatory factor. Different regions for callus formation were also evaluated, such as the gap region, the periosteum and the periosteum border. Each stimulus was computed using the finite element method, and the callus shape was optimised using the steepest descent method.The results demonstrated that the inflammatory factor approach, the interfragmentary strain and the second invariant of the deviatoric strain tensor over the inner gap provided the best results when compared with histological callus shapes. Therefore, this work suggests that callus growth can be an optimal mechanobiological response to either local mechanical instability and/or local inflammatory reaction.  相似文献   
7.
【目的】研究以白木香[Aquilaria sinensis (Lour.) Gilg]根为外植体的愈伤组织诱导条件。【方法】选择白木香2种来源的根,考察不同灭菌条件、不同激素浓度组合对愈伤组织诱导的影响。【结果】实生苗根以0.01 mg/mL的HgCl2溶液灭菌3 min最佳,适合诱导愈伤组织的培养基为MS+0.1 mg/L 2,4-二氯苯氧乙酸(2,4-D)+0.1 mg/L 6-苄氨基嘌呤(6-BA);无菌苗根在添加1.0 mg/L萘乙酸(NAA)和0.8 mg/L 6-BA的MS培养基上可达到最高的愈伤组织诱导率。【结论】获得了2种来源白木香根的愈伤组织;单独使用生长素2,4-D时诱导率较低,添加6-BA后可显著提高愈伤组织的诱导率和生长势。  相似文献   
8.
目的用气相色谱-质谱联用法分析川芎愈伤组织及悬浮培养物中的化学成分。方法建立川芎愈伤组织及悬浮培养体系,收集愈伤组织及连续三代的悬浮培养物,采用气相色谱-质谱联用法进行川芎愈伤组织及悬浮培养物化学成分的分析。结果川芎愈伤组织及悬浮培养物含有相似的成分,但与原植物中的成分区别很大,原植物中的主要活性成分在愈伤组织及悬浮培养物中也未发现。结论愈伤组织及悬浮培养物的特性与原植物有很大的区别。  相似文献   
9.
Introduction Formation of new blood vessels is essential for the process of fracture healing.Materials and methods We investigated the expression of the angiogenic factor pleiotrophin/HB-GAM in a closed fracture model in rats by immunohistochemical methods.Results Histologically, 5 days after fracture the callus was predominantly composed of fibrous tissue. On day 10 a prominent chondral callus connected both ends of the fractured tibia. There was a continuous transition from the chondral callus to the newly formed bone adjacent to the corticalis of the tibia. On day 15 the amount of woven bone had increased, and in 3 of 5 animals the proximal and distal tibiae were connected by a bridge of woven bone. Pleiotrophin could be immunostained in fibroblasts and endothelial cells of the fibrous tissue between the fractured tibia ends. The chondral callus remained largely pleiotrophin-negative. Only single chondrocytes adjacent to the newly formed bone were pleiotrophin-positive. On days 10 and 15 strong immunoreactivity for pleiotrophin in the well vascularized, newly formed, woven bone was detectable. Osteoblasts, endothelial cells and fibroblasts were strongly pleiotrophin-positive.Conclusions These results show the presence of the angiogenic peptide pleiotrophin during fracture healing.  相似文献   
10.
Introduction Aim of this retrospective study was to obtain a functional outcome following callus distraction and phalangization of the thumb after traumatic amputation in the middle one-third.Materials and methods From January 1998 to June 2001, 12 patients were treated in a staged procedure starting with corticotomy and continuous distraction (1 mm/day) of the first metacarpal bone using a unilateral external fixator device. After distraction until day 31 (range 25–35 days), the first metacarpal bone was stabilized with a plate, and phalangization was performed.Results At follow-up 1 year after surgery, the thumb was lengthened to 25–35 mm (average 28 mm) in all but 1 patient. In 1 patient a bone graft from the iliac crest had to be interposed. Pinch grip improved by 45%; grip strength improved by 55%. The function/symptom score from the DASH questionnaire was 25 points (range 16–38 points). In a 'pick-up test' all patients were able to pick up a pencil, they were able to write and could hold a full cup of water. Nine patients were able to pick up a paper clip, and 8 patients could hold a 1-liter bottle of water.Conclusion Callus distraction can be considered a suitable procedure to reconstruct an amputated thumb levelled at the middle one-third. Additional phalangization proved essential as it deepened the first web space, enabling good motion and grasp. Callus formation was delayed in elderly patients, but adequate lengthening and bone healing also occurred in this age group. The procedure will not be as beneficial in cases of osteoarthritis of the trapezometacarpal joint or when coverage of the stump is insufficient. The DASH questionnaire is very helpful in evaluating the effect of thumb reconstruction on the entire upper limb.  相似文献   
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