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101.
Ki-Won Kim Kee-Yong Ha Jun-Seok Lee Suk-Woo Nam Young-Kyun Woo Tae-Hong Lim Howard S. An 《The spine journal》2009,9(4):323-329
Background contextIt was recently demonstrated that the postnatal transition from a notochordal to a fibrocartilaginous nucleus pulposus (NP) is accomplished exogenously by chondrocytes migrating from hyaline cartilage end plates (CEs) into the ectopic notochordal NP region. Although our previous in vivo studies showed evidences for the migration of CE chondrocyte from hyaline CEs into the notochordal NP, it is unknown whether CE chondrocytes of the intervertebral disc (IVD) really have a motile property. In addition, the effect of notochordal cells on this property has not been elucidated.PurposeThe purpose of this in vitro study was to demonstrate whether CE chondrocytes of the IVD are capable of migration, and whether there is any biological link between notochordal cells and CE chondrocytes that may regulate the CE chondrocyte migration.Study design/settingIn vitro cell migration assays were performed using rat IVDs.MethodsNotochordal cells and chondrocytes were obtained from the NP and CE tissues, respectively, and were cultured separately. The different numbers of notochordal cells and the supernatant (conditioned medium) that contained soluble factors produced by notochordal cells were used to demonstrate their effects on the migration of CE chondrocytes. Bovine serum albumin (BSA) and lysophosphatidic acid (LPA) were used as negative and positive controls, respectively.ResultsCompared with BSA, LPA, notochordal cells (N=4×, 2×, 1×, and 0.5×105), and its conditioned media (unconcentrated and fivefold concentrated) significantly increased migration of CE chondrocytes (p<.05 in all comparisons). Particularly, notochordal cells and its conditioned media increased migration in a number- and concentration-dependent manner, respectively.ConclusionsThis study demonstrates that CE chondrocytes of the IVD are capable of migration and that soluble factors produced by notochordal cells stimulate the migration. These results provide a plausible explanation to the question of why CE chondrocytes of the IVD migrate into the ectopic NP region during the natural transition from the notochordal to fibrocartilaginous NP. 相似文献
102.
103.
Mark Sisco MD ; Jerome D. Chao MD ; Injoong Kim MD ; Jon E. Mogford PhD ; Tanya N. Mayadas PhD ; Thomas A. Mustoe MD 《Wound repair and regeneration》2007,15(4):566-571
The Mac-1 integrin is an important mediator of migration and inflammatory activation of neutrophils and monocytes. However, the role of Mac-1 in modulating macrophage emigration and activation and its subsequent impact on cutaneous wound healing have not been fully elucidated. To examine the significance of Mac-1 to murine wound healing, we measured epithelialization and granulation tissue formation in partial-thickness ear wounds and full-thickness head wounds, respectively, in Mac-1-deficient mice. Wounds were histologically analyzed at postwounding days 3, 5, and 7. The gap measured between the leading edges of inward-migrating granulation tissue was significantly increased in knockout mice compared with control animals at day 5 (3.8+/-0.3 vs. 2.6+/-0.5 mm; p<0.001) and day 7 (2.2+/-0.4 vs. 0.96+/-0.73 mm; p=0.005). Epithelial gap measurements were also increased in knockout mice vs. wild-type controls at days 3 (0.62+/-0.02 vs. 0.54+/-0.07 mm; p<0.05) and 5 (0.58+/-0.06 vs. 0.39+/-0.08 mm; p<0.001). Immunohistochemistry showed equal numbers of macrophages in knockout and control wounds. These findings show that Mac-1 is required for normal wound healing but that the attenuation in the deposition of granulation tissue and wound epithelialization in Mac-1 knockout mice is not associated with decreased monocyte migration into the wound. 相似文献
104.
Je-Yong Choi Hyung-Jong Kim Yong-Chan Lee Byoung-Ouck Cho Ha-Soo Seong Michael Cho Seong-Gon Kim 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(3):321-328
OBJECTIVE: Pamidronate has been studied as a therapeutic drug for various osteopenic diseases. However, avascular osteonecrosis in the jawbone has been recently reported in patients receiving pamidronate. The objective of this study was to examine the effect of pamidronate on bone regeneration in a controlled animal model. MATERIALS AND METHODS: To determine the effect of parmidronate on bone healing in a local bony defect area, a rabbit calvarial bony defect model was used and poly L-lactide-co-glycolide (PLGA) used as a drug carrier material. Four defect groups were made in each rabbit calvaria and the defects were treated as follows: untreated bony defect (group 1), PLGA only (group 2), 2 mg of pamidronate with PLGA (group 3), and 3 mg of pamidronate with PLGA (group 4). Bone healing was evaluated by radiography and histology at 1, 2, 4, 6, and 8 weeks after surgery. RESULTS: In radiographic analysis, radiopacity was lower in pamidronate groups than non-operated rabbit calvarial bone at all observation points (P < .05). In histological analysis, the initial bone formation at 1 week was not different among groups, but it was much lower in the pamidronate groups than in the control or PLGA group after 2 weeks. Newly formed bone at 1 week underwent avascular necrosis after 2 weeks in both pamidronate groups. Avascular necrosis was not observed until 8 weeks in both topically applied pamidronate groups. CONCLUSION: Collectively, pamidronate inhibits bone healing in rabbit calvarial bony defect and it may explain the avascular necrosis of the jaws in patients receiving pamidronate. 相似文献
105.
目的探讨两种单静脉入路法和动静脉双入路法治疗PDA各自的优缺点及最佳适应症,为PDA患者选择合理介入治疗方法提供依据。方法103例PDA患者经三种不同介入方法治疗,其中单静脉入路超声法37例,单静脉入路造影法14例,动静脉双入路法52例。PDA的位置、形态、大小经不同方法观察,单静脉超声法经超声观察,单静脉造影法在PDA内或降主动脉近PDA口外造影观察,动静脉双入路在主动脉弓降部侧位造影观察。选择合适型号的Amplatzer伞经股静脉建立的轨道进行封堵。术后15 min经胸超声及心脏听诊判断有无分流。术前、术后均行血流动力学测定,术后3 d、1个月复查超声心动图,观察大动脉水平有无分流及动脉导管未闭再通。结果103例患者全部一次封堵成功,技术成功率100%。术中操作平均透视时间(10.45±4.35)min,心导管检查测肺动脉收缩压由术前轻度增高[(33.2±3.11)mmHg]降为正常[(22.03±5.3)mmHg]。术后即刻所有患者心前区双期连续性杂音消失,术后无残余分流,无任何并发症发生,随访1个月未发生动脉水平分流及动脉导管再通。结论单静脉入路Amplatzer封堵器治疗动脉导管未闭简化了手术程序,不用或减少造影剂用量,缩短了操作透视时间,手术成功率高,疗效可靠,值得推广应用。 相似文献
106.
术中即时扩张皮肤面积增加与压力和时间的量效关系 总被引:1,自引:1,他引:0
目的探讨术中即时扩张皮肤面积增加与压力、时间的量效关系。方法用6头小型猪,压力参数分别为15、20、25kPa,时间参数为60、90min,配对组成6个实验组,1个对照组,36个实验部位。在每只猪背部皮下均匀埋置100ml圆形扩张器6个,术中即时扩张皮肤,观察扩张皮肤各径线移位特点,计算面积变化。结果扩张区周边皮肤向中心蠕动和扩张器表面皮肤伸展同时存在。扩张皮肤面积扩大在一定范围内与压力、时间增加成正比,20kPa、60min组合增幅最大,此后增幅明显减少,并逐渐引发皮肤病理性改变。结论皮肤可在一定范围内通过术中即时扩张获得面积有效增加。 相似文献
107.
通过对 5 0 0例经尿 11项试纸检查阴性的标本 ,沉渣镜检发现尚有 6 7例阳性 ,阳性率为 13.4 %。提示尿沉渣镜检 ,不失为泌尿系统疾病检查的必要手段不应忽视及偏废 相似文献
108.
下肢动脉硬化闭塞症的外科治疗 总被引:2,自引:0,他引:2
目的:探讨外科治疗下肢动脉硬化闭塞症的临床经验。方法:从1995年7月~2002年7月共对292例(313条肢体)动脉硬化闭塞症病人进行外科治疗,其中20条患肢施行解剖外血管重建术,38条患肢施行了腔内外科治疗或合并开放性血管重建手术,255条患肢施行了开放性手术重建下肢血供。结果:手术成功者患肢的踝肱指数与术前比较显著增加(P<0.01),症状得到明显改善。平均随访时间3.1年(0.5~7年),解剖外重建组移植血管一期通畅率为56%,腔内外科组通畅率为78%,开放性手术组通畅率为72%。结论:病人的全身情况、动脉病变的范围和程度是选择下肢动脉硬化闭塞症外科治疗方法的主要依据,为取得较好的长期通畅率和临床效果需要重视围手术期处理和术后随访。 相似文献
109.
兰敏 《四川生殖卫生学院学报》2005,(5):18-21
胡塞尔继承了西方哲学史上的本质主义路线,严格区分事实和本质、形式本质和实质本质,提出了他的现象学本质观。本质观使我们对“本质”的了解获得了从柏拉图主义和洛克主义、实在论和唯名论非此即彼之争中挣脱出来的可能。 相似文献
110.
低能级体外冲击波碎石治疗肾鹿角形结石 总被引:2,自引:1,他引:1
目的探讨低能级体外冲击波碎石(extracorporeal shock wave lithortripsy,ESWL)治疗肾鹿角形结石的效果. 方法对18例鹿角形结石进行体外冲击波治疗.碎石能级1~3级,冲击次数1 800~3 000次,脉冲间隔60 ~80次/min,工作电压10~12.75 kV. 若结石直径>3 cm,在碎石前预先插入双J管,防止石街形成.对直径>4 mm的残余结石,再次行ESWL,直至结石完全消失. 结果所有病人耐受良好,治疗结束能自行回家.除1例碎石失败外,余17例经ESWL治疗成功.治疗3~9次,至完全排除结石.66例次(66/77,85.7%)术后有1~2次肉眼血尿.5例出现石街,长1.9~5.2 cm,4例石街经再次碎石成功,1例输尿管镜取石. 结论低能级ESWL治疗肾鹿角形结石是一种安全、有效的方法. 相似文献