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31.
胫骨平台解剖型钢板的结构特点及临床运用 总被引:6,自引:0,他引:6
目的探讨解剖型钢板治疗胫骨平台骨折的结构特点。方法2001年1月-2003年12月,应用解剖型钢板治疗胫骨平台骨折34例,其中男20例,女14例;年龄23~54岁,平均38.7岁。结果34例均获得随访,随访时间8~28个月,平均19个月。术后1个月膝关节屈曲70°~120°,平均90.2°;术后3个月膝关节屈曲90°~135°,平均110.3°;术后半年膝关节屈曲100°~135°,平均125.0°。按Merchant评分,终末随访时优18例,良12例,可4例。术后无切口皮肤坏死、感染和钢板松动及断裂。结论解剖钢板治疗胫骨平台骨折效果满意,其三维结构符合胫骨平台解剖特点,可以提供持续坚强的固定,有利术后膝关节早期活动,骨折愈合率高,并发症少。 相似文献
32.
2001年3月~2004年4月,我院应用锁骨钩钢板治疗NeerⅡ型锁骨远端骨折,疗效满意。1材料与方法1.1病例资料本组25例,男14例,女11例,年龄13~65岁。左侧9例,右侧16例;横形13例,斜形12例。均为NeerⅡ型新鲜骨折,其中ⅡB型骨折7例。受伤至入院时间30min~6d。X线片显示均为锁骨外1/3骨折。1.2治疗方法颈丛麻醉,采用改良Herry手术切口。行骨折复位,用锁骨钩钢板的钩端钩住肩峰后下方,外展及上举肩关节使骨折端紧密嵌合,钛板塑形预弯后紧贴锁骨上方的骨皮质,用松质骨和皮质骨螺钉分别固定远近骨折端,重叠缝合三角肌及斜方肌纤维脚。对ⅡB型喙锁… 相似文献
33.
对管碟法测定Nisin效价的条件进行了研究,考察了几个参数的影响,得出了Nisin测定的最佳条件:90mm培养皿中培养基加量为15mL,Na2HPO4·12H2O质量浓度1g/dL,菌悬液浓度109CFU/mL,琼脂质量浓度1g/dL,培养基pH值7.0,牛津杯中样品加液量100μL.在此条件下,Nisin效价在5~100IU/mL,其对数值与抑菌圈直径有较好的线性关系. 相似文献
34.
采用硬组织切片技术和ABC免疫组织化学技术,对5例16~20周胎儿股骨骺板、干骺瑞进行胰岛素样生长因子-I(简称IGF-I)的定位研究。观察到骺板储备区、增生区和肥大区均有IGF-I免疫反应阳住的软骨细胞;干骺端存在一定数量的IGF-I阳性成骨细胞,部分类骨质和骨基质也有阳性反应物沉积,少数破骨细胞也呈IGF-I免疫阳性反应。作者同时讨论了在硬组织切片上进行免疫组化染色的可能性和IGF-I在骨组织内的作用。 相似文献
35.
Shigenori Inao Yoshiharu Takemitsu H. Edward Conrad 《Journal of orthopaedic science》1996,1(6):369-375
Monolayer cultures of 12-day chick embryo chondrocytes from the regions of dividing (zone 1), elongated (zone 2), and hypertrophied
(zone 3) chondrocytes in the tibial cpiphyseal growth plate were analyzed for their capacity to synthesize types II, IX, X,
and XI collagens. Synthesis of types II and IX collagens was markedly elevated in the zone 2 culture, while type X collagen
synthesis was maximal in zone 3. Type XI collagen was synthesized at low rates in all cultures, with some elevation of its
rate in zones 2 and 3. In terms of mol percent of total collagen synthesis, types II and IX collagens decreased from zone
1 to zone 3, while type X collagen increased progressively. Thus, the composition of the extracellular collagens produced
by the different zones changed markedly during chondrocyte differentiation. In addition, type X collagen was released exclusively
into the culture medium, whereas type XI collagen was retained in the extracellular cell-associated matrix. In contrast, types
II and IX collagens were found in both the culture medium and the cell matrix pools. Although types II and IX collagens showed
similar changes during differentiation, the synthetic molar ratios of these two collagens varied from 3 to 18 in different
cultures, suggesting that the synthesis of these two products is not tightly coupled in these cells. 相似文献
36.
Deformation due to growth disturbance after epiphyseal fractures around the knee may involve more than the primarily injured
epiphysis, as spontaneous corrective growth of the opposite epiphyseal plate can take place in an attempt to maintain overall
alignment of the leg. As a result, there will be an inclination in the knee joint line if corrective osteotomy is only performed
for the primary angulation. We report two cases of this complex deformity in which corrective osteotomies of both the distal
femur and the proximal tibia were performed, resulting in correct alignment of the overall leg axis and knee joint axis.
Received: 25 May 1996 Accepted: 20 November 1996 相似文献
37.
应力松弛接骨板对骨几何形态和力学性能影响的实验观察 总被引:2,自引:0,他引:2
《中华医学杂志》1995,(7)
作者采用粘弹性材料制成垫圈置于接骨板螺孔与螺丝钉之间,构成应力松弛接骨板系统。实验证实,有垫与无垫接骨板在固定早期对模拟骨的应力遮挡作用相同,固定8周后垫圈出现明显变形和破坏,使有垫接骨板的应力遮挡率从第10周起明显低于无垫接骨板。有垫接骨板固定的胫骨骨质疏松明显轻于无垫组,固定20周后,有垫组的胫骨髓腔径明显小于无垫组,骨皮质厚度和胫骨抗弯强度均明显大于无垫组(P<0.05~0.01)。说明应力松弛接骨板系统早期具有与坚强接骨板相同的固定作用,后期其应力遮挡效应可逐渐减小,避免严重的骨质疏松和骨力学性能下降。 相似文献
38.
G. J. Breur M. D. Lapierre K. Kazmierczak K. M. Stechuchak G. P. McCabe 《Calcified tissue international》1997,61(5):418-425
In this study, we tested the hypotheses that (a) both the domain volume (volume of the cell and the matrix it has formed)
and matrix volume of juxtametaphyseal hypertrophic chondrocytes in the growth plate is tightly controlled, and that (b) the
domain volume of juxtametaphyseal hypertrophic chondrocytes is a strong determinant of the rate of bone length growth. We
analyzed the rate of bone length growth (oxytetracycline labeling techniques) and nine stereologic and kinetic parameters
related to the juxtametaphyseal chondrocytic domain in the proximal and distal radial and tibial growth plates of 21- and
35-day-old rats. The domain volume increased with increasing growth rates, independent of the location of the growth plate
and the age of the animal. Within age groups, the matrix volume per cell increased with increasing growth rates, but an identical
growth plate had the same matrix volume per cell in 21- and 35-day-old rats. The most suitable regression model (R
2= 0.992) to describe the rate of bone length growth included the mean volume of juxtametaphyseal hypertrophic chondrocytes
and the mean rate of cell loss/cell proliferation. This relationship was independent of the location of the growth plate and
the age of the animal. The data suggest that the domain volume of juxtametaphyseal hypertrophic chondrocytes, as well as the
matrix volume produced per cell, may be tightly regulated. In addition, the volume of juxtametaphyseal hypertrophic chondrocytes
and the rate of cell loss/rate of cell proliferation may play the most important role in the determination of the rate of
bone length growth.
Received: 2 December 1996 / Accepted: 24 March 1997 相似文献
39.
目的:比较肩锁钩板和传统克氏针内固定治疗不稳定性锁骨外侧段骨折的疗效。方法:54例不稳定性锁骨外侧段骨折的患者接受了手术治疗,内固定分别是锁骨钩板或克氏针,根据国外的锁骨外侧段骨折肩部功能评价标准进行6-12个月的术后随访,随访结果运用统计学方法进行分析处理,结果:克氏针内固定组的手术优良率为77.3%,并发症发生率为27.3%,骨折愈合率为81.8%;锁骨钩板内固定组的手术优良率为100%,并发症发生率为3.1%,骨折愈合率100%。两组数据统计学差异有显著性,结论:在不稳定性锁骨外侧段骨折的手术治疗中,锁骨钩板较传统克氏针内固定有较高的手术优良率和骨折愈合率,且并发症的发生率较低,因此,它是一种疗效满意的内固定方法。 相似文献
40.
In Vitro Evaluation of Platelet/Biomaterial Interactions in an Epifluorescent Video Microscopy Combined with a Parallel Plate Flow Cell 总被引:1,自引:0,他引:1
Nobuchika Kawagoishi Chisato Nojiri Kazuhisa Senshu Takayuki Kido Hirofumi Nagai Toshiyuki Kanamori Kiyotaka Sakai Hitoshi Koyanagi† Tetsuzo Akutsu 《Artificial organs》1994,18(8):588-595
Abstract: Suitable evaluation systems are critical for ranking various biomaterials in order to develop a method to design and synthesize nonthrombogenic biomaterials. We have recently developed an in vitro test system to evaluate platelet/biomaterial interactions in whole blood. The system consists of a parallel plate flow cell and epifluorescent video microscopy (EVM). A glass coverslip coated with a polymer was incorporated into the flow cell, and blood was perfused using a syringe pump via a polymer–coated PVC tubing connected to the flow cell. Whole human blood was anticoagulated with heparin (2 U/ml), and the platelets were labeled with the fluorescent dye mepacrine (5 μM). This system permitted real–time and dynamic observations of platelet/biomaterial interactions in whole blood under a defined flow condition. In order to evaluate the feasibility of this system, two different segmented polyether–polyurethanes (SPEUs), PU–PTMG(650) and PU–PTMG(2000), were chosen as test polymers. Surface characteristics verified with electron spectroscopy for chemical analysis (ESCA) and contact angle measurements showed similar results in both SPEUs. Blood was perfused at a wall shear rate of 200 s–1 for 20 min. Excitation light was applied for 2 s at 1 min intervals. The real–time image was then analyzed at each time point for the percentage of surface area of platelet coverage. Plasma β–thromboglobulin (β–TG) levels were also measured before and after each run. PU–PTMG(650) showed a significantly higher number of adhered platelets than PU–PTMG(2000) at each time point. β–TG levels of PU–PTMG(650) were also higher than those of PU–PTMG(2000), which is comparable to the results of EVM. Thus, this EVM system has been proven to be an excellent and highly sensitive in vitro analytical method for evaluating platelet/biomaterial interactions. 相似文献