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51.
[目的]探讨一氧化氮在激素性股骨头坏死发病中的作用.[方法]制作激素性股骨头坏死家兔模型后,在不同时期测定血浆及软骨中的一氧化氮含量,观察股骨头的组织学变化.[结果]激素性股骨头坏死家兔血浆和软骨中的一氧化氮含量均明显升高,股骨头髓腔中的脂肪细胞明显增多,骨小梁变细、稀疏及断裂,空骨陷窝明显增多.电子显微镜观察见骨细胞核染色质浓缩,体积缩小,胞浆中内质网及线粒体肿胀变性,粗面内质网上的核糖体脱落.[结论]一氧化氮参与激素性股骨头坏死的发病过程. 相似文献
52.
目的探讨胸大肌肌皮瓣术后发生脂肪液化的相关危险因素。方法对1998年5月至2005年12月采用胸大肌肌皮瓣修复口腔癌术后组织缺损的82例中10例术后发生不同程度脂肪液化的病例,进行Logistic回归分析。结果Logistic单因素回归分析结果表明:肥胖、电刀切开皮下组织、皮岛设计低于第7肋、吸烟等因素与胸大肌肌皮瓣术后发生脂肪液化有关;Logistic多因素回归分析结果表明:胸大肌肌皮瓣术后发生脂肪液化与肥胖、电刀切开皮下组织、皮岛设计低于第7肋等因素有关,而与吸烟无关。结论肥胖、电刀切开皮下组织、皮岛设计低于第7肋等因素是胸大肌肌皮瓣术后发生脂肪液化的危险因素。 相似文献
53.
Noninvasive Intracranial Cerebral Flow Velocity Evaluation in the Emergency Department by Emergency Physicians 总被引:2,自引:0,他引:2
Michael Shafé MD Michael Blaivas MD RDMS Edmond Hooker MD Leigh Straus BS 《Academic emergency medicine》2004,11(7):774-777
Transcranial Doppler (TCD) is an accepted modality for the evaluation of cerebral blood flow velocities. OBJECTIVES: The purpose of this study was to test the feasibility of bedside TCD measurement in the emergency department (ED) with critically ill, intubated patients. METHODS: A prospective convenience sample of patients presenting to a university hospital over a two-month period underwent TCD evaluation of the middle cerebral artery. Intubated patients with head trauma and any patient requiring tracheal intubation were eligible. A 2-MHz Doppler probe was positioned over the temporal bone to acquire blood flow velocities. An emergency medicine resident and research assistant obtained measurements. Continuous TCD tracings were recorded on a video cassette recorder tape for quality assurance review and data collection. Vital signs and therapeutic interventions were also recorded. Flow velocities were measured in cm/s; the peak Resistance Index (RI) was calculated for each patient. RESULTS: A total of 30 patients were enrolled in the study. Adequate tracings were obtained in 25 patients (83%) without a disruption of resuscitation. Tracings could not be obtained in five patients; they were listed as TCD failures. However, in two of these patients, adequate flow velocity tracings were obtained after resuscitation. Four patients were evaluated during tracheal intubation. One patient was monitored successfully during cardiopulmonary resuscitation. The median time required for data acquisition was 1.9 minutes. The mean highest RI for those who expired was 0.84. For those who survived, the mean highest RI was 0.52. The difference of 0.32 was statistically significant (p = 0.04). CONCLUSIONS: Noninvasive blood flow velocity monitoring of the middle cerebral artery using TCD is feasible in the ED when performed at the bedside on intubated patients with traumatic brain injury and others during tracheal intubation and resuscitation. 相似文献
54.
Femoral and lateral cutaneous nerve of the thigh blocks have been performed in a group of 50 children; the method has not previously been described in paediatric practice. The technique was judged to have been successful in 48 (96%) of the children. There were no early or late complications. It is concluded that these blocks are easy to perform, even in small children and infants, and that they can produce reliable postoperative analgesia for a variety of orthopaedic and plastic procedures. 相似文献
55.
56.
复方积雪草有效组分对人肾小管上皮细胞补体C3表达的影响 总被引:2,自引:1,他引:1
目的:探讨复方积雪草有效组分——积雪草苷/大黄素干预肿瘤坏死因子-α(TNF-α)诱导的人肾近曲小管上皮细胞(HPTEC)补体C3 mRNA及蛋白的表达水平。方法:采用HPTEC,模型组TNF-α 10ng/ml诱导,治疗组在TNF-α诱导的同时,以不同浓度的积雪草苷、大黄素以及积雪草苷合大黄素进行干预,于24h后分别提取细胞RNA及上清,应用逆转录-聚合酶链反应(RT—PCR)和酶链免疫方法(ELISA)分别检测HPTEC C3 mRNA和蛋白的表达。结果:正常HPTEC具有C3 mRNA和蛋白表达,经TNF-α诱导后G表达明显上调,用不同浓度的积雪草苷、大黄素以及积雪草苷合大黄素干预后,C3 mRNA及蛋白水平表达出现不同程度的下调,呈一定的剂量依赖关系和协同作用。结论:复方积雪草有效组分能够抑制炎性细胞因子TNF-α上调所致的肾局部G过度产生。 相似文献
57.
58.
同种异体骨支撑架微创治疗股骨头坏死的临床研究 总被引:1,自引:0,他引:1
目的应用改良髓芯减压术结合同种异体骨支撑架加自体骨和脱钙骨基质(decalcified bone matrix,DBM)治疗早期股骨头坏死,探索早期股骨头坏死的微创治疗方法。方法2004年1月~2005年4月,23例24个髋关节采用经大转子下通过股骨颈钻隧道至股骨头骨坏死区,将装有自体松质骨和DBM的同种异体骨支撑架经隧道拧入骨坏死区直至软骨下骨约5mm处,隧道远端用自体髂骨填塞。观察手术前后Harris评分变化、x线影像学表现及是否需进一步治疗。结果本组所有患者均获得随访,平均随访19(12—27)个月,以最后一次随访资料作为最终评价依据。Harris评分,术前优良率为43.5%(10/23)。术后优良率为91.3%(21/23)。22侧髋关节影像学表现保持稳定,无明显并发症发生。结论同种异体骨支撑架植入结合自体松质骨和DBM治疗成人股骨头坏死,增加了股骨头负重区软骨下骨的机械支撑,成骨作用强,有利于股骨头坏死的修复与重建,同时,不破坏患者股骨头本身的血液供应,创伤小,操作简单,值得临床推广使用。 相似文献
59.
60.
Osteochondral Fracture of the Fourth Metatarsal Head Treated by Open Reduction and Internal Fixation
Praveen K.R. Mereddy MBBS MSOrth DNB Orth MRCSEd Andrew Molloy MBchB MRCS FRCS Michael S. Hennessy BSc MBchB FRCSEd 《The Journal of foot and ankle surgery》2007,46(4):320-322
Fracture of the metatarsal head is uncommon, and reports of isolated osteochondral fracture of the metatarsal head are rare. Because of the distal location of the fracture, it is difficult to achieve and maintain reduction, and potential complications include avascular necrosis and subchondral fatigue fracture. The authors present a case of an osteochondral fracture in a 40-year-old man, which was treated by open reduction and internal fixation with a single twist-off screw, with good results 12 months postoperatively. 相似文献