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51.
目的:观察自体干细胞动员对骨创伤大鼠的免疫功能的保护作用,为战创伤后的免疫抑制及继发性感染、系统性炎症反应等治疗提供依据。方法:挤压折断法复制大鼠双后肢股骨骨折模型,于致伤后0、24、48h连续给模型动物肌肉注射GM—CSF20μg/kg,致伤后72h细胞增殖法检测T、B淋巴细胞活性,ELISA法检测血清IL-1、IL-2、IFN-7、TNF—α浓度,自动系列化分析法检测C3、CA、IgM、IgG浓度,称重法观察脾重与体重的比例变化。结果:股骨骨折模型大鼠致伤后72h,GM—CSF动员骨髓干细胞组大鼠的T、B淋巴细胞活性和血清IFN-γ、IL-2浓度高于对照组(P〈0.01),IL-1、TNF—α浓度低于对照组(P〈0.01),血清C3、CA、IgM、IgG浓度及脾/体重比值高于对照组(P〈0.01)。结论:GM—CSF动员自体干细胞动员对大鼠骨创伤诱导的免疫功能抑制具有保护作用。 相似文献
52.
Hossam B El-Zawawy Corey S Gill Rick W Wright Linda J Sandell 《Journal of orthopaedic research》2006,24(12):2150-2158
Smoking delays the healing process and increases morbidity associated with many common musculoskeletal disorders, including long bone fracture. In the current study, a murine model of tibial fracture healing was used to test the hypothesis that smoking delays chondrogenesis after fracture. Mice were divided into two groups, a nonsmoking control group and a group exposed to cigarette smoke for 1 month prior to surgical tibial fracture. Mice were euthanized at 7, 14, and 28 days after surgery. The outcomes measured were immunohistochemical staining for type II collagen protein expression as a marker of cartilage matrix and proliferating cell nuclear antigen (PCNA) staining to measure proliferation at the site of injury. Toluidine blue staining and histomorphometry were used to quantify areas of cartilaginous and noncartilaginous fracture callus. Radiographs were analyzed for evidence of remodeling after injury. At day 7 after injury, mice exposed to cigarette smoke had a smaller fracture callus with less cartilage matrix compared to controls. Proliferation was present at high levels in both groups at this time point, but proliferating cells had a more immature morphology in the smoking group. At day 14, chondrogenesis was more active in smokers compared to controls, while a higher percentage of bone was present in the control animals. At day 28, X-ray analysis revealed a larger fracture callus remaining in the smoking animals. Together, these findings show that the chondrogenic phase of tibial fracture healing is delayed by smoking. This study represents, to our knowledge, the first analysis of molecular and cellular mechanisms of healing in a smoking mouse fracture model. 相似文献
53.
不同钉位布局影响股骨颈骨折内固定效应的生物力学研究 总被引:12,自引:4,他引:8
目的:观察应用多枚钉内固定治疗股骨颈骨折时采取不同钉位布局对骨折断端固定效应的影响,为临床操作中寻求最佳钉位布局奠定基础。方法:通过特制壮年人体尸骨股骨颈骨折模型,进行直视下解剖复位后,分别应用3钉倒三角形、3钉正三角形和双钉平行3种不同钉位布局内固定方法完成内固定。在生物力学万能试验机上进行轴向压缩和扭转实验,观察不同生物应力下断端相对的位移距离、轴向刚度、水平剪切刚度和扭转强度等项目,取得试验数据后经统计学处理,进行组间对比,观察其差异的显著性。结果:在3种钉位布局的内固定方法之中,以股骨矩核心下2~3mm处进钉位为下位顶点的倒三角形钉位布局能获得最坚强的固定效应,相同应力下其位移距离最小而各项刚度最大;而股骨矩核心上位和中下位双钉固定法固定效应最差,表现为相同应力下位移距离最大和各项刚度最小。结论:尽可能选择以股骨矩核心下2~3mm处进钉位为下位顶点的倒三角钉位布局法,尽可能减少应用双钉位布局法。 相似文献
54.
MD Charles D. Hummer III MD PhD Richard H. Rothman MD William J. Hozack 《The Journal of arthroplasty》1995,10(6)
Catastrophic failure of two zirconia—ceramic modular femoral heads occurred, despite the theoretical improved toughness of zirconia—ceramic relative to alumina—ceramic. This experience led the authors to return to cobalt—chromium as the metal of choice for articulation against polyethylene in total hip arthroplasty. 相似文献
55.
胸腰椎爆裂骨折椎管内骨片侵入倾向与对策 总被引:5,自引:0,他引:5
根据98例中获得随访的39例的X线、CT和MRI(24例)影像学资料,分析胸腰椎爆裂骨折椎管内骨片侵入倾向及对策。将爆裂骨折侵入椎管分为四类八型,宜采用Harrington器械钢丝或椎弓根螺钉钢板轴向撑开系统,使骨折复位,椎管容积恢复,毋需行后路椎管减压。本组取得良好效果。仅对骨片游离型需要切开椎管直接摘除骨片。 相似文献
56.
加压滑动鹅头钉治疗股骨转子间骨折的临床与实验研究 总被引:27,自引:0,他引:27
探讨加压滑动鹅头钉在治疗股骨转子间骨折中的作用。临床应用45例。男34例,女11例。平均年龄61岁。稳定型13例,不稳定型32例。经临床应用和生物力学实验测定,结果表明:(1)对不稳定型转子间骨折,恢复小转子区内后侧皮质骨的连续性在骨折的稳定中具有重要作用。(2)内后侧骨折块解剖复位,加压螺丝钉固定或大转子骨折端加压螺丝钉固定能显著增强加压滑动鹅头钉的固定作用,明显提高不稳定型转子间骨折的术后稳定性。(3)该装置设计合理,性能坚固,对转子间骨折具有很强的固定作用,能有效地达到早期下床和避免长期卧床的目的,是目前临床最理想的内固定装置。 相似文献
57.
The objective of this study was to estimate the incidence of hip fracture in the canton of Vaud, Switzerland (total population 584 000), for the period 1986–1991 using routine hospital discharge data collected by the Cantonal Service of Statistical Research and Information (SCRIS). For the survey period, the estimated average annual crude incidence rate of hip fractures was 167 per 100 000 persons aged 20 or older (241 for women and 84 for men). For the population aged 50 years or older, the crude incidence rate was 388 per 100 000 persons (546 for women and 185 for men). The average annual age-specific rates rose exponentially by successive 5-year age groups. The median age of patients at the time of the fracture was 82 years in women and 74 years in men. There was no significant difference between the total number of cervical and trochanteric fractures. Between the ages of 20 and 84 years, the cumulative risk for a woman to be admitted to hospital with a hip fracture was twice that of a man (15.8% vs 7.8%). From 1986 to 1991, the age- and sex-adjusted incidence, like the ratio of cervical to trochanteric fractures, did not show any significant trend, although it was consistent with an increase in men (p=0.09). However, the annual number of fractures rose from 644 to 776, particularly among very aged men. The mean length of stay in the acute care hospital fell from 38 days in 1986 to 25 days in 1991. Finally, the comparison of these results with those obtained in 1986 for the same population from more exhaustive sources has confirmed the provision of a consistent, although overestimated, assessment of hip fracture incidence by means of these routine hospital statistics in the canton of Vaud, Switzerland. 相似文献
58.
Differences in hip axis and femoral neck length in premenopausal women of Polynesian, Asian and European origin 总被引:4,自引:0,他引:4
There are substantial inter-racial differences in hip fracture incidence. Studies in several different ethnic groups have suggested that differences in the length of the femoral neck may contribute to these. The present study assesses femoral neck and hip axis lengths in three ethnic groups in which it has not been documented previously (Chinese, Indians and Polynesians) and compares these values with those in Europeans. Lengths were measured from dual-energy X-ray absorptiometry scans of the proximal femur in normal premenopausal women (n=225). The Polynesian (1.65 m) and European (1.64 m) women were significantly taller than the two Asian groups (mean height in each, 1.58 m). There were also differences in mean body weight, the Polynesians being the heaviest (76 kg) and the Chinese the lightest (53 kg). Femoral neck lengths were (mean + SD) Chinese 61.5+4.4 mm, Indian 61.5+5.1 mm, Polynesian 68.2+4.3 mm and Europeans 66.0+4.8 mm. Hip axis lengths were Chinese 98.0+5.6 mm, Indian 94.5+5.2 mm, Polynesian 106.4 ± 5.3 mm and European 102.3+5.3 mm. Each of the other groups were significantly different from the Europeans for both variables and, in general, this remained so after height adjustment. These data suggest that shorter femoral necks are common to the major Asian racial groups. However, in contrast to all other ethnic groups studied, Polynesians have longer femoral necks than Europeans and their low incidence of hip fracture is not explicable, therefore, in terms of their femoral neck length. This suggests that either higher bone density or other more subtle differences in proximal femoral geometry must account for the low hip fracture incidence in Polynesians. 相似文献
59.
Frank Diesner Dr. med. Dag Moskopp Christoph Schul Hansdetlef Wassmann 《Neurosurgical review》1997,20(4):274-277
A 21-year-old man was injured by a tailboard of a truck. He suffered a severe head injury with bilateral depressed skull fractures necessitating surgical decompression. On admission to the hospital the patient showed bending to pain stimuli (Glasgow Coma Score 5). Anisocoria was noticed from the beginning. Initial intracranial pressure (ICP), measured 3 hours after injury, was 30 mm Hg, and the cerebral perfusion pressure (CPP) was 70 mm Hg. During surgical elevation of the skull fracture on the right side an unexplainable rise of ICP to values of 100 mm Hg occurred, which corresponded to the mean arterial blood pressure (MAP). At the same time both pupils were dilated and fixed indicating a lack of cerebral perfusion. Due to immediate trephination of the opposite side, the ICP was lowered to values below 20 mm Hg, and sufficient cerebral perfusion (above 50 mm Hg) was regained. The patient showed a good recovery and was transferred to a rehabilitation center 5 weeks after injury.This case report emphasizes the importance of early and continuous intracranial pressure monitoring for adequate therapy in neurosurgical emergencies. 相似文献
60.
Priv.-Doz. Dr. V. Nutz M. Peschen 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1992,377(6):372-377
Summary A duplex ultrasound system was used to examine the blood flow of the common femoral artery in ten young patients with fractures of the lower extremities. Two patients had fractures of both legs. In eight patients the blood flow in the injuried leg was comparable with that in the not injured leg. The flow alterations were measured on 3–7 different days over a period of 6–224 days after trauma. All patients showed a significant (to twice or three times that before injury) increase in blood flow in the injured leg a few days after trauma and/or operation, whereas the blood flow in the uninjured leg remained the same or even decreased a little. In the case of undisturbed fracture healing the change in blood flow disappeared within 8–12 weeks, corresponding to fracture consolidation. When fracture healing was delayed and/or further operations on the injured leg were necessary, the blood flow was increased for much longer. The hemodynamics of an injured extremity are compared with those reported elsewhere in the literature. The increased demand for oxygen or energy can explain the changes only in part. Another function of the reflective increase in blood flow could be the temperature increase in the extremity.
Doppler-sonographische durchblutungsmessungen der unteren extremität des menschenII. Hämodynamik nach trauma und operation
Zusammenfassung Mittels Doppler-sonographischer Durchblutungsmessung wurde die Hämodynamik der verletzten Extremität an 10 jungen Patienten mit Frakturen der unteren Extremität untersucht. Bei 8 Patienten konnte die Durchblutung des verletzten Beins mit der unverletzten Gegenseite verglichen werden. Die Messungen erfolgten an 3–7 verschiedenen Tagen in einem Zeitraum von 6–224 Tagen nach dem Unfall. An allen verletzten Extremitäten steigt die Durchblutung wenige Tage nach dem Unfall und/oder der Operation deutlich um das 2- bis 3fache an, während die Durchblutung des unverletzten Beins niedrig bleibt. Bei einem ungestörten klinischen Verlauf sinkt die Durchblutung in 8–12 Wochen wieder. Heilungsstörungen und weitere Operationen an dem Bein verzögern diese Normalisierung deutlich. Diese Ergebnisse werden mit anderen Untersuchungen der Literatur verglichen. Ursache und Funktion der hämodynamischen Änderungen könnte u. a. in einer reflektorischen Temperaturerhöhung zu sehen sein.相似文献