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41.
Effect of autocontrol micromotion intramedullary interlocking nail on fracture healing: an experimental study 总被引:1,自引:0,他引:1
Objective: To investigate the effect of autocontrol micromotion locking nail ( AMLN ) on experimental fracture healing and its mechanism. Methods: 16 goats undergoing both sides of transverse osteotomy of the femoral shafts were fixed intramedullary with AMLN and Gross-Kempf (GK) nail, respectively. The follow-up time was 7, 14, 28 and 56 days. Roentgenographic, biomechanical, histological, scanning electromicroscopic and biochemical analyses were done. Results: (1) The strength of anticompression, antiflexion and antitorsion in the fractural end in the AMLN-fixed group was higher than that of GK nail-fixed group; whereas, the rate of stress shelter in the fractured end decreased significantly (P<0.01). (2) The content of the total collagen, insoluble collagen, calcium and phosphate in the AMLN-fixed group was higher than that in the GK nail-fixed group (P<0.05). (3) Histological observation and quantitative analysis of calluses revealed that AMLN could promote the growth of bridge calluses and periosteum calluses. Hence the facture healing and remolding process achieved early, which was much better than traditional GK nail fixation. (P<0.05). (4) 7-14 days postoperation, the calluses of AMLN-fixed group was flourish and camellarly arranged and the collagen fibril formed constantly in the absorption lacuna of bone trabecula. 28-56 days postoperation, the collagen fibril was flourish around the absorption lacuna and was parallel to the bone's longitudinal axis. Active bony absorption and formation were seen, so was remolding and rebuilding. Haversian system was intact and the bony structural net was very tenacious because of the deposition of calcium salt. None of the above findings was observed in the GK nailfixed group. Conclusions: The design of AMLN accords well with the plastic fixation theory. As the geometry ametabolic system constituted by the intramedullary fixation instruments and the proximal and distal end of the fracture is very firm and stable, the disturbance to the physical stress distributed in the fractural end is light. The generation and conduct of the intermittent physical stress between the fractural parts could reach the balance between stress conduct and stress protection. The feature that the healing and remolding take place at the same time speeds up the fractural healing process. 相似文献
42.
Objective: To study the calcium channel reaction of human Leydig cells induced by hCG/ATP at different extracellular calcium ion concentrations. Methods: The Leydig cell calcium ion concentration was examined with laser confocal microscope, when the cells were stimulated with hCG/ATP at different extracellular calcium contrations. Results: With calcium-containing extracellular fluid, the Leydig cells were sensitive to hCG stimulation and when the extracellular fluid was calcium-free, the Leydig cells did not respond to the stimulation. However, the Leydig cells did respond to ATP stimulation no matter the extracellular fluid contained calcium or not. Conclusion: In human Leydig cells, there are calcium channels sensitive to hCG and ATP. The extracellular calcium ion concentration plays an important role in the regulation of Leydig cell metabolism by hCG/ATP. 相似文献
43.
44.
Objective: To analyze quantitatively the synergistic and antagonistic effects of combined oxymatrine (OMT) and 5-fluorouracil (5-GU)
on a cell line of human liver cancer (HepG2) with median-effect principle in vitro. Methods: The median-effect principle and MTT method were used in the quantitative analysis of effects of the two drugs. Results: Cytotoxic activity of the individual drugs enhanced as drug concentration increased. As fa=0.41, a CI equal to 1 indicated
additivity; fa<0.41, a CI less than 1 indicated synergy; and fa>0.41, a CI greater than 1 indicated antagonism. The sequence
of administration did not influence the cytotoxic activity of the combined antitumor drugs. The ratio of drug concentration
was a factor that can influence the killing effect. Conclusion: The combined drugs interaction (CI<1) was synergistic at lower concentration and antagonistic at higher concentration. The
ratio of drug concentration is a factor that can influence the killing effect.
Biography: HE Song(1965–), male, doctor of medicine, associate professor, Chongqing Medical University, majors in gastroenterology. 相似文献
45.
在定量的构效关系研究中,多重回归分析选人的参数,多是用穷举所有方程实现的。本文提出一种改进的逐步回归算法,计算实例表明,是个行之有效的方法。 相似文献
46.
47.
目的探讨护理管理路径在应用佩尔地平治疗的重度子痫前期病人的效果,以期达到最佳的治疗效果,并减少并发症的发生。方法将用佩尔地平针治疗的重度子痫前期的病人486例随机分为两组,一组按常规护理,另一组按制定的护理管理路径护理。结果患者依从性对照组为168例,占70%;观察组为228例,占92.68%,P〈0.05,其差异有统计学意义。胎死宫内发生率对照组为9.16%,观察组为0.81%,P〈0.05,其差异有统计学意义。血压的稳定性对照组为36.3%,观察组为97.6%,P〈0.05,其差异有统计学意义。结论护理管理路径可以提高重度妊娠高血压疾病的治疗效果,减少并发症的发生。 相似文献
48.
胃肠道肿瘤病人围手术期细胞因子及蛋白质代谢的变化 总被引:4,自引:0,他引:4
目的 :探讨胃肠道肿瘤病人手术后肿瘤坏死因子 α (TNF α)、白介素 6 (IL 6 )、白介素 10 (IL 10 )的变化以及与蛋白质代谢的关系。 方法 :用酶联免疫法 (ELISA)检测 19例胃肠道肿瘤根治术病人术前和术后 1、3、5天血清TNF α、IL 6和IL 10水平 ,同时检测蛋白质分解代谢相关指标、2 4h尿中尿素和肌酐排泄量。 结果 :胃肠道肿瘤根治术后病人TNF α呈下降趋势 ,术后第 1天较术前明显下降 (P <0 .0 5 )。IL 6和IL 10术后升高 (P <0 .0 1) ,尤以术后第 1天升高明显。术后 2 4h尿中尿素和肌酐排泄量明显升高。 结论 :胃肠道肿瘤根治术后病人IL 6和IL 10的升高支持手术应激导致的细胞因子释放变化 ,但TNF α呈下降趋势 ,可能与胃肠道肿瘤病人术前TNF α的高表达有关。术后蛋白质分解代谢增加 ,可能与细胞因子IL 6和IL 10的升高有关。 相似文献
49.
Objective: To study the relationship between transaldolase activity, protein expression and testosterone synthesis in Leydig cells of pubertal mice. Methods: Leydig cells were cultured for 2 hours and 8 hours, to the Stimulation Group, hCG was added and to the Controls, only the vehicle. The testosterone concentration was then determined by enzyme-linked immunoadsordent assay (ELISA) and the transaldolase activity and protein expression by Western blot. Results: (1) Both the testosterone concentration and the transaldolase activity in both Stimulation Groups were significantly higher than those in the corresponding Controls (2 h: p<0.05-0.01; 8 h: P<0.001); (2) The ratios of the A isoform, the B isoform and the total transaldolase protein to β-actin between the Stimulation and Control Groups did not differ signifi-cantly. Conclusion: hCG stimulates the transaldolase activity as well as the testosterone synthesis in the Leydig cells of pubertal mice, indicating a positive relationship between them. 相似文献
50.
Kousaku Matsubara M.D. Kei Suzuki M.D. Ying Wei Lin M.D. Toshiyuki Yamamoto M.D. Shigeru Ohta M.D. 《Pediatrics international》1991,33(4):482-487
We present two female siblings with familial juvenile nephronophthisis (FJN) which was diagnosed at the early stage of renal failure. Diagnosis was made during the investigation of anemia in case 1 and by a subsequent family survey in case 2. Most patients with FJN are not identified until the terminal stage of renal failure and such cases have rarely been reported in Japan. Case 2 had a reduction in the maximum urinary concentration ability but no azotemia, and among the FJN patients reported in Japan so far she has the least advanced renal disease. Histological examination of the renal biopsy in case 1 showed typical findings of FJN, such as thickening and lamination of the tubular basement membrane (TBM), interstitial fibrosis, and round cell infiltration of the interstitium. In case 2, renal biopsy revealed an irregular marked thickening of the TBM with trivial interstitial changes and a normal glomerular appearance. The histology of these two cases suggests that the TBM may be the primary site affected in FJN. 相似文献