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91.
F. B. Christensen M. Lind S. P. Eiskjær K. Thomsen E. S. Hansen C. E. Bünger 《European spine journal》1999,8(1):54-60
The capacity of the individual patient to initiate osteoblast proliferation as a predictor for successful lumbar spinal fusion
has not yet been reported. The objectives of this study were, first, to analyze the relationship between in vitro osteoblast
proliferation and clinical bony fusion in the individual patient in order to predict the fusion outcome and, second, to measure
the effect of preoperative tobacco smoking on osteoblast proliferation. Sixty-one patients (mean age 46 years) underwent posterolateral
lumbar fusion in the period 1994–1995. Thirty-eight patients received CD pedicle screw implants and 23 received posterolateral
fusions alone. During surgery, autogenous iliac bone was harvested and 1 g of trabecular bone without blood or bone marrow
was then isolated for cell culturing. The cultures were classified as excellent (confluence within 4 weeks), good (confluence
between 4 and 6 weeks) and poor (no or poor growth). Spine fusion was evaluated by two independent observers from plain anterior-posterior,
lateral, and flexion/extension radiographs taken 1 year postoperatively, and the functional outcome was measured by the Dallas
Pain Questionnaire (DPQ). Twenty-three patients had excellent, 19 good, and 19 poor in vitro osteoblast proliferation. Bony
fusion was obtained in 77% of patients: 83% in the CD instrumentation group and 70% in the non-instrumentation group (NS).
There was no significant correlation between osteoblast proliferation and spinal fusion or functional outcomes when analyzing
the CD instrumentation and non-instrumentation groups together or separately. Elderly patients had a significantly poorer
osteoblast proliferation than younger patients (P < 0.008). Preoperative tobacco consumption had no discernible effect on osteoblast proliferation, and no correlation between
smoking and fusion was found. Further refinement of autologous osteoblast culturing may provide a biological tool for selection
of patients who require biological enhancement of their bone fusion capacity. The poorer osteoblast proliferation related
to advanced age supports the important negative biological influence of age on bony fusion. However, with more sensitive testing
and better discrimination, other results are possible – or can in any event not be excluded.
Received: 17 April 1998 Revised: 10 September 1998 Accepted: 12 October 1998 相似文献
92.
93.
The CG clip is a device designed for use in expansive open-door laminoplasty with both a spacer and means of attachment in a single unit. It provides an effective technique for open-door laminoplasty, which obviates the need for bone grafting or complex internal fixation by providing dynamic stabilization of the open laminae. A number of techniques for expansive open-door laminoplasty have been devised for the decompression of the spinal cord and nerve roots in cervical spondylotic myeloradiculopathy. Each of these techniques requires some degree of internal fixation and/or bone grafting. The CG clip is a single device which is composed of both a spacer and a spring clip for attachment. The spacer ensures a 4-5-mm sagittal expansion of the cervical spinal canal. The spacer is held in place along the lateral cut margin of the laminae by a spring-wound titanium clip, which folds over the central spinous process of the unilaterally elevated laminar block. In all respects except for grafting and internal fixation, the surgery is performed as for a standard expansive open-door laminoplasty. Sixteen of the first 24 patients to undergo this procedure improved at least one point on the Neurosurgical Cervical Spine Scale. Of the remaining eight patients, four remained the same and four deteriorated. The authors have found the CG-clip laminoplasty technique quick and easy to perform, with early results in the treatment of cervical spondylotic myeloradiculopathy consistent with those of other decompressive procedures. 相似文献
94.
在海拔3417m对18名健康世居藏族和16名移居汉族用Jeager气体代谢自动分析系统和心阴抗图测定了无氧阈和最大摄氧量时的SV、CO、PEP/LVET和SaO2。结果显示:在海拔3417m测得AT值明显低于海平面;世居藏族AT出现较晚,并且AT时的功率、VO2、MV、HR、CO、SV均高于移居汉族,而PET/LVET比值小于移居组;两组的SV峰值出现时间不同,蕊居组在AT或AT以后出现的占72% 相似文献
95.
<正>The risk of cardiovascular disease increases along with aging. There are increasing interests in researches on the protective effects of hormone replacement therapy (HRT) on cardiovascular system in postmenopausal women. In this article we will review how we have explored the evidence of different sex hormones on blood vessels since 1996. The results showed that low-dose HRT significantly protected cardiovascular system in postmenopausal women. However, the high-dose 17β-estradiol (E2), with or without progesterone (P) or testosterone (T),or any hormone alone, as their concentrations increase, may even inhibit the protective effects of low-dose HRT on blood vessels. 相似文献
96.
目的 初步观察重组人N末端脂多糖结合蛋白 (tLBP)对细菌脂多糖 (LPS)致伤小鼠的保护效应。 方法 选用雄性昆明小鼠 70只 ,随机分为致伤组 1(2 1只 ) :腹腔内注射LPS 10 0ng;保护组 1(2 1只 ) :腹腔内注射 10 0ngLPS 40mgtLBP;对照组 (8只 ) :腹腔内注射等渗盐水。于注射后15、30min及 1、3、6、12、2 4h测定 3组动物血清丙氨酸转氨酶 (ALT)及肿瘤坏死因子α(TNF α)的含量 ,并观察其肝、肺组织的病理学改变。另设致伤组 2及保护组 2各 10只 ,分别腹腔内注射LPS 4 0 0ng及4 0 0ngLPS 40mgtLBP,观察伤后 2 4h内动物的死亡数。 结果 保护组 1与致伤组 1血清ALT含量分别于伤后 12、6h到达峰值 ,各为 (41.0 0± 4 .5 8)、(99.5 0± 6 2 .6 3)U L,前者的升高幅度显著低于后者 (P <0.0 1);两组血清TNF α含量均于伤后 3h到达峰值 ,各为 (35 .96± 7.33)、(42 .4 9± 4 .79)fmol ml,保护组 1的升高幅度低于致伤组 1。与致伤组 1比较 ,保护组 1肝细胞变性程度明显减轻 ,未见肝细胞散在坏死病变 ;肺组织充血有不同程度减轻 ,肺泡腔内、支气管内炎性渗出明显减弱。致伤组2伤后 2 4h死亡 9只 ,保护组 2死亡 3只。 结论 初步认为重组人tLBP具有一定的生物学活性 ,对LPS致伤小鼠具有一定保护作用。 相似文献
97.
重组合异种骨加钢板内固定治疗胫骨平台骨折 总被引:5,自引:3,他引:5
目的探讨重组合异种骨植骨加钢板内固定治疗胫骨平台骨折的临床疗效. 方法 2001年6月~2003年3月,采用切开复位、重组合异种骨植骨加支持钢板(T型或L型)内固定,治疗胫骨平台骨折32例.男20例,女12例,年龄18~69岁,平均38岁.交通伤23例,坠落伤5例,砸伤4例,均为新鲜闭合性骨折.受伤至手术时间2~7天.术中植骨量2~6 g. 结果全部患者经9~23个月随访,胫骨平台骨折愈合良好,未见关节面下陷,重组合异种骨未见移动、吸收.按Pasmussen评分标准,优16例,良12例,可3例,差1例,优良率达87.5%. 结论重组合异种骨植骨加支持钢板内固定治疗胫骨平台骨折效果良好,避免了取髂骨植骨及其并发症的发生. 相似文献
98.
目的 探讨门腔分流术后病人给予含丙氨酰 谷氨酰胺双肽 (Ala GLN)肠外营养 (PN)的安全性 ;观察其营养支持的效果 ,及对肠道通透性的影响。方法 16例病人随机分为两组。对照组(n =7)接受不含GLN的PN ;实验组 (n =9)接受含Ala GLN双肽的PN。两组自术后第 1天起给予等氮、等热量的PN共 7d ,于PN前后分别测定血清前白蛋白、氮平衡变化、血清GLN浓度、血氨、尿乳果糖 /甘露醇排泄率比值 (L/Mratio)、生化和临床指标的变化。结果 对照组术后血清GLN水平比术前显著降低 ,术后实验组GLN水平 (5 77± 4 2 ) μmol/L显著 (P =0 0 0 9)高于对照组术后水平 (499± 6 1)μmol/L ;两组术前的L/M比率均明显高于国人正常水平 ,术后对照组L/M水平 (0 0 95± 0 0 34)显著 (P=0 0 4 5 )高于实验组 (0 0 6 4± 0 0 2 3) ;两组累积氮平衡无显著性差异 ,但实验组第 5~ 7天期间氮平衡要明显优于对照组 ,实验组第 5天氮平衡 (- 15 3± 4 6 9)mg·kg-1·d-1显著 (P =0 0 4 3)好于对照组 (-92 7± 90 5 )mg·kg-1·d-1;对照组术后血清前白蛋白水平较术前显著下降 ,实验组术后血清前白蛋白水平 (0 2 6 9± 0 0 37)g/L显著 (P =0 0 0 1)高于对照组 (0 199± 0 0 2 7)g/L ;两组术后血氨水平相比无统计学意义 ;生 相似文献
99.
目的 探讨重组人生长激素治疗各种阻塞性黄疸病人的临床应用价值。方法 选择90例阻塞性黄疸病人随机分为实验组45例和对照组45例,在常规应用营养治疗上的基础上对实验组病人加用重组人生长激素治疗,观察两组病人术后氮平衡、营养生化指标、肝功能和AKBR进行统计学处理并计算平均住院日、死亡率了解其效果。结果 重组人生长激素治疗阻塞性黄疸较对照组疗效好。结论 重组人生长激素能改善阻塞性黄疸胆道引流术后病人的肝功能.促进组织愈合,减轻术后疲劳,具有良好的临床应用价值. 相似文献
100.
Objective To investigate the changes of perioperative right ventricular function after pulmonary resction. Methods 45 cases of pulmonary resection were divided into four groups.Group Ⅰwas wedge resection(n = 10), GroupⅡ was lobectomy(n = 19), Group Ⅲ was double lobectomy(n=7)and Group Ⅳ was pneumonectomy(n=9). The changes of CVP, PAMP, PEP/ET, Sa, VTIs, RVSP, Ea/Aa, and Tel were evaluated by traditional ultrasonic and tissue Doppler ultrasonic techniques at different time inter- vals (pre-operation, 5-7 days orland 1 month post-operation), Results Compared with the pre-operation CVP, the indexes of all groups have no significant changes post-operatively. Wedge resection didn' t obviously influence right cardiac after load and systolic function/diastolic function. No evidet changes detected in Tei pre-and post-operatively. However, the indexes (PAMP, RVSP and PEP/ET ratio) reflecting right cardiac afterload evidently increased at post-pneumonectomy or lobectomy group5- 7 days post-opera- tive. All these reflect the decrease of Tei, which was more obvious in pneumonectomy than in lobectomy group. Right cardiac after- load, systolic/diastolic function and Tel index recovered to pre-operative level 1 month post-operation in single lobectomy group. But the above indicators, especially the Tel, were still high in double lobectomy and pmeunonectomy groups 1 morth post-operation.Tei index is positively correlated with PAMP and is weakly correlated with PET/ET ratio and Ea/Aa ratio. Conclusion Pulmonary wedge resection doesn't evidently influence right cardiac function. However, right cardiac diastolic function evidently decreases temporarily at lobectomy group. The systolic function and diastolic funetions decrease after double-lobectomy and pneumonectomy and it's more evident in pneumonectomy group. Though the right cardiac afterloads of lobectomy, double lobectomy and pneumonectomy groupa all increase significantly post-operativlye, only the former recover to pre-operative level 1 month after surgery. 相似文献