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21.
髓内固定系统治疗下肢骨折临床应用   总被引:1,自引:0,他引:1  
目的:探索髓内固定系统在下肢骨折治疗中的操作原理。方法:认真术前掌握髓内钉系统的设计和操作,结合对骨折部位、类型及生物力学分析等选择内固定,通过对下肢骨折157例的术中观察及术后摄片对照等探索髓内钉系统的操作情况。结果:术后摄片骨折达解剖或功能复位,随诊3~24月,优良率为94.88%。结论:下肢骨折治疗中,髓内钉系统是一种优良的支撑、复位、固定器材:术前认真分析骨折类型及力学特点,有助于术中顺利操作和骨折的坚强固定。  相似文献   
22.
本文测量了桡骨与尺骨各100例,其中桡骨15项指标,尺骨14项指标。并用IBM·PC—XT计算机DBASEⅢ数据库管理系统进行了统计分析以及用桡、尺骨最大长分别与桡、尺骨其它各项指标间进行直线相关分析,建立了25个回归方程。  相似文献   
23.
本实验以免载体股直肌为实验模型,研究了该肌在一定脉冲电流刺激下其初长度与收缩力、肌张力及肌力变化的相互关系。同时测定了正常生理状态下兔伸屈膝时股直肌拉长度的变化。结果表明:兔股直肌延长在1.0cm内时,肌力随初长度的延长而增大,超过1.0cm时增大已不明显(p<0.0 1),1.0cm与股直肌的生理最大延长度1.1cm相似。说明兔股直肌的初长度变化不应超过生理最大延长度。而人的骨骼肌与哺乳动物的骨骼肌没有本质的区别,因此,人骨骼肌的初长度变化也不应超过生理最大延长度。肌腱转位后的活动范围应在原位的生理活动范围内,才能发挥最佳收缩效应。  相似文献   
24.
The recently developed method of total vertical projections is illustrated to estimate the total dendritic length of a human Substantia Nigra neuron. Next, the length of the different orders of dendritic branches, and the mean segment length for each order - commonly regarded as important parameters in neuron physiology - are also estimated. Finally, it is shown how to estimate the mean dendritic length in a population of neurons from vertical slices of arbitrary and unknown thickness. Being unbiased and highly efficient, the proposed methods offer interesting alternatives to current procedures used for the metric analysis of neuron arborizations.  相似文献   
25.
ABSTRACT Embryotoxicity and teratogenicity of cadmium (Cd) and modulation of its effects by N-acetyl-L-cysteine (NAC) were evaluated in mice. Pregnant ICR mice were intraperitoneally injected with 3.5 mg/kg of CdCl2 on day 10 or 11 of gestation (vaginal plug = day 0). Pregnant mice were pretreated with 160 mg/kg of NAC intravenously 2 hours before dosing with CdCl2. Pregnant mice were killed on day 17 of gestation. Fetuses were examined for external malformations, especially limb malformations, cleft palate and abnormal palatal rugae. There was little difference in body weight gain of dams during the gestation period in the groups treated with NAC plus Cd as compared with the groups treated with Cd alone. Pretreatment with 160 mg/kg of NAC decreased the fetal mortality, incidence of cleft palate and abnormal palatal rugae induced by Cd on day 11. On day 10, pretreatment with NAC decreased the incidence of Cd induced abnormal palatal rugae. These results clearly indicate that NAC exerts protective effects against embryotoxicity and teratogenicity of Cd.  相似文献   
26.
In spite of significant advances in the knowledge and understanding of the multi-factorial nature of obesity, many questions regarding the specific consequences of the disease remain unanswered. In particular, there is a relative dearth of information pertaining to the functional limitations imposed by overweight and obesity. The limited number of studies to date have mainly focused on the effect of obesity on the temporospatial characteristics of walking, plantar foot pressures, muscular strength and, to a lesser extent, postural balance. Collectively, these studies have implied that the functional limitations imposed by the additional loading of the locomotor system in obesity result in aberrant mechanics and the potential for musculoskeletal injury. Despite the greater prevalence of musculoskeletal disorders in the obese, there has been surprisingly little empirical investigation pertaining to the biomechanics of activities of daily living or into the mechanical and neuromuscular factors that may predispose the obese to injury. A better appreciation of the implications of increased levels of body adiposity on the movement capabilities of the obese would afford a greater opportunity to provide meaningful support in preventing, treating and managing the condition and its sequelae. Moreover, there is an urgent need to establish the physical consequences of continued repetitive loading of major structures of the body, particularly of the lower limbs in the obese, during the diverse range of activities of daily living.  相似文献   
27.
食管癌3p24等位基因LOH及其扩增产物克隆的研究   总被引:4,自引:0,他引:4  
目的;研究3p24EAβMD位点与食管癌的关系。为寻找该位点附近可能存在的抑癌基因奠定基础。方法:采用PCR—RFLP法检测45例食管癌患者3p24位点杂合缺失情况。并对该片段进行克隆。结果:在22例食管癌信息个体中共检出9例杂合缺失。并通过序列分析可知变化为点突变。结论:3p24EAβMD较高的杂合缺失率显示该位点附近可能存在潜在的抑癌基因。  相似文献   
28.
采用限制性酶切片段长度多态性分析法,检测在胃癌高发区庄河检出的19例胃癌高系家族成员胃蛋白酶原C基因多态性,发现三种常见片段及一种稀有片段。对其中4例携带稀有片段的受检者进行了胃镜追踪观察,2.5年后发现1例早期胃癌。本文对此作了初步探讨。  相似文献   
29.
本文报告我院外科1985~1987年,使用应变容积描绘仪检查下肢深静脉机能不全30例。其中28例同时行Doppler超声检查,27例行静脉造影检查。介绍了测量最大静脉输出量,最大静脉逆流量和静脉再充盈时间的方法和结果,叙述了该技术的原理,在诊断下肢静脉机能不全时,应变应变容积描绘仪是较好的无损伤检查技术。  相似文献   
30.
This paper describes a technique of fasciocutaneous island flaps used in reconstruction of the lower limb. It is very versatile and some 26 individual flaps in 22 patients have been used to reconstruct skeletal and soft tissue problems from the popliteal fossa to the ankle joint. These longitudinally designed flaps made up of a trilaminate of skin, subcutaneous fat and fascia are aligned within the dermatomal precincts. The most important location for such flap design is along the peroneal compartment sitting within the L5 dermatome and incorporating the superficial peroneal nerve. It can be lengthened as far as the lateral malleolus and is an excellent reconstructive method to close defects over the lower third of the tibia. The medial compartment of the leg employing the saphenous nerve (L4 dermatome) is another area for fasciocutaneous island flap reconstruction, but use is restricted to the upper two-thirds of the tibial area. Posteriorly the island flap design sits along the S2 dermatome, this time incorporating the sural nerve to reconstruct defects of the calf and can be extended to include problems of the popliteal fossa. In the overall flap technique, the age of the patient is not a contraindication and cases with peripheral vascular disease have been treated successfully. The flaps may extend up to a 5:1 ratio in dimension. The operating time can be considerably shortened.  相似文献   
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