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端粒和端粒酶与永生化软骨细胞 总被引:4,自引:0,他引:4
关节软骨细胞凋亡与增殖在正常情况下处于动态平衡,维持着关节软骨的细胞数量及其形态和功能的稳定.软骨细胞凋亡过盛可能是关节软骨退变发展成骨关节炎的重要原因之一.关节软骨细胞凋亡主要与细胞的端粒长短和端粒酶活性密切相关,细胞的"末端复制问题"使端粒不可避免地随着复制逐渐缩短,端粒缩短达到临界长度时细胞将无法进行分裂而凋亡.端粒酶的逆转录反应弥补细胞分裂过程的端粒丢失,实现细胞永生化.有效地调控软骨细胞端粒长短、端粒酶的活性,抑制关节软骨细胞过度凋亡,意味着部分软骨细胞功能得以保护,延缓或减轻关节软骨的退变,促进软骨修复,从而缓解症状,改善关节功能,可能为骨关节炎的防治开辟一条新途径. 相似文献
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培养软骨、关节软骨、生长板和半月板的超微结构研究 总被引:1,自引:1,他引:0
目的 探讨离心管培养软骨作为移植材料的可能性。方法 3周龄兔关节软骨细胞经离心管培养2周形成软骨,另取6周龄兔肱骨头关节软骨、肱骨近端生长板和半月板,并对4种软骨进行透射电镜观察,比较其软骨细胞和细胞外基质结构。结果 离心管培养软骨具有独特的超微结构,与关节软骨和生长板有一定的相似性,而与半月板有明显区别。4种软骨都形成了各自不同的细胞和细胞外基质特征,离心管培养软骨呈现典型软骨细胞凋亡,生长板表现“黑暗”软骨细胞,关节软骨和半月板未见细胞凋亡。结论 离心管培养软骨具有独特的超微结构,可作为关节软骨和生长板的移植物。 相似文献
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关节内骨折后受损软骨细胞凋亡的实验研究 总被引:3,自引:1,他引:2
目的:探讨关节内骨折后受损软骨的变化。方法:利用冲击在兔膝关节内造成骨折,利用TUNEL、流式细胞计数,透射电镜、DAPI染色等方法对受损软骨进行动态观察。结果:关节内骨折后2周,受损软骨细胞发生坏死及凋亡。1月后受损软骨细胞仍进行性凋亡。3-6月后,损伤软骨周围的细胞也发生凋亡,损伤部软骨细胞增生,其中部分增生细胞凋亡。结论:关节内骨折后软骨细胞进行性凋亡,可能是创伤后骨关节炎发生的原因之一。 相似文献
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Improved sexual behavior in male rats treated with a Chinese herbal extract: hormonal and neuronal implications 总被引:3,自引:0,他引:3
Zanoli P Benelli A Zavatti M Rivasi M Baraldi C Baraldi M 《Asian journal of andrology》2008,10(6):937-945
Aim: To investigate the influence of an extract obtained from five Chinese medicinal plants on sexual behavior of adult male rats. Methods: The extract was administered at doses of 30, 60 and 120 mg/kg by oral gavage, acutely (one time, 45 min before mating test) or subchronically (daily for 10 days) in sexually potent and sexually sluggish/impotent rats. Sexual behavior, serum levels of luteinizing hormone (LH) and testosterone (T) were evaluated in treated rats and compared with controls receiving vehicle. The effect of the extract on central dopaminergic neurotransmission was assessed in the nucleus accumbens using a microdialysis technique. Results: In sexually potent rats, both acute and subchronic treatment with the extract dosed at 30 and 60 mg/kg reduced mount latency and intromission latency. In sluggish/impotent rats, the acutely administered extract at the dose of 60 mg/kg shortened ejaculation latency, whereas subchronically administered at the doses of 30 and 60 mg/kg, reduced mount, intromission and ejaculation latencies, increasing also the percentage of mounting and ejaculating rats. The extract dosed at 60 mg/kg significantly increased LH and T following acute and subchronic administration and increased 3,4-dihydroxyphenylacetic acid levels in the nucleus accumbens, 30 min after the acute administration. Conclusion: The improvement in both appetitive and consummatory components of sexual behavior observed in male rats treated with the extract could be ascribed to increased serum T level in parallel with the activation of the central dopaminergic system. 相似文献
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脊柱侧凸矫形手术早期并发症的处理及预防 总被引:2,自引:2,他引:0
随着脊柱外科的迅速发展,国内越来越多的医院已经或正在开展各类脊柱侧凸的手术治疗。但由于脊柱作为人体的支柱,其解剖关系复杂,邻近有许多重要组织和器官,因此手术相关并发症并不少见,也不容忽视。如何预防和减少手术并发症,已经是迫在眉睫的任务,需要我们不断研究和深入探讨。根据发生时间可将手术并发症分为术中、术后早期及术后晚期并发症。现对脊柱侧凸矫形手术中及术后早期并发症的的处理及预防进行分析。 相似文献
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一般性骨折愈合过程分为血肿机化演进期、原始骨痂形成期和骨痂改造塑形期;而骨质疏松性骨折愈合过程分为纤维骨痂期、软骨骨痂期和骨性骨痂期。骨质疏松性骨折愈合的组织学观察表明,纤维骨痂期主要是成纤维细胞合成Ⅲ型胶原;软骨骨痂期主要是成软骨细胞合成、分泌Ⅱ型胶原;骨性骨痂期主要是随着软骨内成骨的出现和发展,Ⅱ型胶原消失,逐渐由抗张力性能较强的Ⅰ型胶原所取代。一般来说,实验性骨质疏松性骨折的愈合方式与一般性骨折愈合方式相似,软骨内成骨和膜内成骨共同参与了骨质疏松性骨折的修复过程,但以软骨内成骨为主。 相似文献
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2005年7月~2008年10月,我科对7例肱骨髁间粉碎性骨折患者进行切开复位+双钢板内固定治疗,取得满意疗效。
1材料与方法
1.1病例资料本组7例,男5例,女2例,年龄31—65岁:根据Riseborough分型:Ⅲ型2例,Ⅳ型5例(图1A)。1例术前有尺神经损伤症状。 相似文献
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Aim: To investigate the effects of 17β-estradiol (E2), Peganum harmala extract (PHE) and caloric restriction (CR) on various testis parameters during aging. Methods: Twelve-month-old male rats were treated for 6 months with either E2 or PHE, or submitted to CR (40%). Results: Our results show that estrogens and CR are able to protect the male gonad by preventing the decrease of testosterone and E2 levels as well as the decrease of aromatase and estrogen receptor gene expressions. Indeed, E2, PHE and CR treatments induced an increase in the superoxide dismutase activities and decreased the activity of testicular enzymes: gamma-glutamyl transferase, alkaline phosphatase, lactate deshydrogenase as well as the aspartate and lactate transaminases in aged animals. In addition, the testicular catalase and gluthatione peroxidase activities were enhanced in E2, PHE and CR-treated rats compared to untreated animals at 18 months of age. Moreover, the positive effects of estradiol, PHE and CR were further supported by a lower level of lipid peroxidation. Recovery of spermatogenesis was recorded in treated rats. Conclusion: Besides a low caloric diet which is beneficial for spermatogenesis, a protective antioxydant role of estrogens is suggested. Estrogens delay testicular cell damage, which leads to functional senescence and, therefore, estrogens are helpful in protecting the reproductive functions from the adverse effects exerted by reactive oxygen species (ROS) produced in large quanti- ties in the aged testis. 相似文献
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半月板组织工程的研究进展 总被引:1,自引:1,他引:0
半月板损伤临床常见,据美国矫形外科学会2008年的统计资料,美国每年全膝关节置换手术>250000例,其中半月板损伤是骨性关节炎进展的关键因素。然而,半月板仅外周1/3有血液供应,发生于此部位的损伤采用缝合治疗可以愈合;而内侧缘2/3均为无血管区,损伤后自行愈合能力较差,目前临床上针对这类损伤多采用半月板部分切除或全部切除术。 相似文献