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21.
目的 探讨严重创伤后肝细胞凋亡及坏死在急性肝功能障碍发病机制中的作用。方法复制多发性骨折合并休克的大鼠创伤模型,采用 Annexin-V-Flous、碘化丙锭(propidium iodid,PI)双标法经流式细胞仪检测创伤后各时间点肝细胞凋亡与坏死的数量变化,结合光镜、电镜和电泳观察细胞凋亡与坏死,并与肝功能变化相比较。结果创伤后早期肝细胞即发生凋亡和坏死,坏死肝细胞的数量进行性升高,与肝功能变化显著呈正相关;凋亡肝细胞在创伤后3h达高峰,部分凋亡肝细胞发生继发性坏死,其数量与肝功能变化显著正相关。结论肝细胞坏死与凋亡是严重创伤后肝功能损害的重要原因,坏死肝细胞是肝功能损害的直接因素,凋亡肝细胞通过发生继发性坏死加重肝功能损害。  相似文献   
22.
Critical size defect in the canine mandible.   总被引:3,自引:0,他引:3  
OBJECTIVE: The purpose of this study was to determine the minimum size defect in a canine mandible that would not spontaneously heal during the dog's natural life (the critical size defect). STUDY DESIGN: Sixteen adult female mongrel dogs underwent continuity resection on both sides of the mandible to create bilateral defects. In 8 dogs, mandibular defects ranging from 5 to 20 mm were created with periosteal resection. In the other 8 dogs, mandibular defects ranging from 30 to 60 mm were created preserving the periosteum. The dogs were then killed at 6 months and the defects examined using radiographs and histologic analysis. RESULTS: When the periosteum was removed, mandibular defects greater than 15 mm failed to heal across the entire defect. However, when the periosteum was preserved, mandibular defects needed to be greater than 50 mm in order to fail to heal. CONCLUSION: The critical size defect in a canine mandible model is 15 mm when the periosteum is removed and 50 mm when the periosteum is preserved.  相似文献   
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24.
目的 探讨性别因素对接受人工全膝关节表面置换术的膝骨关节炎患者术后功能的影响. 方法 前瞻性研究了 2003年 3月~ 2005年 8月期间行单侧人工全膝关节表面置换术(均使用不保留后交叉韧带后稳定型固定平台假体)的 40例 (40髋 )膝关节骨关节炎患者,男女各 20例( 20膝),对其相关的临床因素用 t检验和χ 2检验进行分析. 结果平均年龄:男 72.6岁、女 70.8岁;病程:男 10.4年、女 9.7年;体重指数:男 26、女 26;术后平均住院时间:男 17 d、女 18 d;止血带使用时间:男 104 min、女 94 min;引流量:男 806 mL、女 742 mL;术前、术后 1周、 2周和 1年的膝关节伸屈度数男分别为 7.0°~ 114.0°、 3.0°~ 91.0°、 0.4°~ 103.0°和 0~ 125.0°,女分别为 8.0°~ 111.0°、 2.0°~ 86.0°、 1.0°~ 98.0°和 0~ 122.0°;术前、术后 1周、 2周和 1年的膝关节活动度:男分别为 108°、 89°、 109°和 123°,女分别为 104°、 87°、 101°和 126°;术前和术后 1年的 HSS评分:男分别为 57、 89分,女分别为 53、 87分.两性别组各时间点的伸屈度数、活动范围及术前和术后 1年的 HSS评分差异无统计学意义 (P >0.05);而同一患者术前和术后 1年的伸屈度数及 HSS评分则差异有统计学意义 (P >0.05). 结论 性别对行全膝关节置换的骨关节炎患者术后功能无明显影响,全膝关节置换能有效缓解骨关节炎相关的疼痛并改善膝关节的功能.  相似文献   
25.
X Dong  M He  X Song  B Lu  Y Yang  S Zhang  N Zhao  L Zhou  Y Li  X Zhu  R Hu 《Diabetic medicine》2007,24(12):1482-1486
AIMS: Our aim was to assess performances of the Cockcroft-Gault and simplified Modification of Diet in Renal Disease (MDRD) formulae in estimating glomerular filtration rate (GFR) in Chinese diabetic populations and their association with vascular risks. METHODS: A total of 1009 patients with Type 2 diabetes were categorized into low estimated GFR groups (GFR < 60 ml/min/1.73 m(2)) and control groups by the two equations. The performances of these formulae were assessed at different stages of kidney function. Carotid artery intima-media thickness (IMT) and the prevalence of diabetic retinopathy or albuminuria were compared among the groups. The ability of these formulae to identify established vascular risk markers using sensitivity, specificity, positive and negative predictive values were also compared. RESULTS: The prevalence of low estimated GFR was 32.7% with the Cockcroft-Gault formula and 5.2% with the MDRD formula, respectively. In low estimated GFR subjects by the MDRD formula, IMT was significantly thicker than those by the Cockcroft-Gault formula (1.2 mm vs. 1.0 mm; P < 0.05), with a higher prevalence of albuminuria (78.4 vs. 52.8%, P < 0.05) and diabetic retinopathy (46.5 vs. 30.5%; P < 0.05). The Cockcroft-Gault formula gave a specificity of 71.7% and a sensitivity of 37.0%, and the MDRD formula gave a specificity of 96.6% and a sensitivity of 7.9% in estimating low GFR relevant for established vascular risks. CONCLUSIONS: These formulae performed differently in Chinese diabetic populations. The simplified MDRD formula is minimally superior to the Cockcroft-Gault formula for its high specificity and positive predictive values in estimating low GFR relevant for vascular risks.  相似文献   
26.
随着"三医改革"的不断深入,医疗市场的竞争日趋激烈,人们对医院管理在生存和发展中的重要作用也日益关注.由于中医院面临着管理理念、资源优化、人才构筑和公平竞争的诸多问题,以往的经验管理已不能适应时代性、国际化的要求.面对瞬息万变的生存环境,需要各级中医医院能够主动参与竞争,充分发挥中医药特色,强化自身优势,对市场的变化迅速作出反应,这对中医医院管理工作提出了更高的要求.  相似文献   
27.
OBJECTIVE: The C2A domain of Synaptotagmin I is a molecular probe for the specific imaging of cell death. Here we test the hypothesis that the uptake of 99mTc-C2A in the acute phase of an infarction is associated with cardiac dysfunction in follow-ups. METHODS: The left coronary artery was occluded in Sprague-Dawley rats for 0, 10, 20, and 30 min. 99mTc-C2A was injected intravenously at 2 h of reperfusion. Anterior planar images were acquired with one million counts on a gamma camera 3 h after injection. 99mTc-C2A uptake was calculated as the total counts in the left ventricle region minus blood pool signal. The in-vivo signal detected was correlated with wall motion score index at 1 and 3 weeks follow-ups measured by echocardiography. RESULTS: 99mTc-C2A uptake was higher with increased ischemic time (2244+/-852, 4054+/-1223, and 6178+/-1451 for 10, 20, and 30 min ischemia, analysis of variance P<0.001). A significant correlation was found between 99mTc-C2A uptake and wall motion score index at 1 week (R=0.800, P=0.0006) and 3 weeks (R=0.810, P=0.0008). CONCLUSION: In this ischemia/reperfusion model, 99mTc-C2A uptake in the acute phase was associated with functional abnormality at 1 and 3 weeks. This demonstrates the potential diagnostic and prognostic value of 99mTc-C2A as a novel imaging agent.  相似文献   
28.
This study evaluated the safety and efficacy of batroxobin in treating hyperfibrinogenemia for secondary stroke prevention. Patients with ischemic stroke or transient ischemic attack (TIA) were measured for plasma fibrinogen levels. Selected participants had concomitant hyperfibrinogenemia (plasma fibrinogen > or = 3.0 g/l). Patients enrolled between 1 July 2003 and 31 December 2004 were treated with batroxobin; patients enrolled between 1 January 2002 and 30 June 2003 were treated without batroxobin. Batroxobin was administered intermittently via intravenous injection at 3-monthly intervals. Patients in both groups were followed for 1 year. Any cerebrovascular events and suspected adverse events were recorded. In total, 112 ischemic stroke/TIA patients with concomitant hyperfibrinogenemia were enrolled, 52 being treated with batroxobin and 60 without batroxobin. Six patients (11.5%) with batroxobin and 16 patients (26.7%) without batroxobin had recurrent cerebral ischemic events during follow-up. Stroke/TIA recurrence in patients without batroxobin was higher than that in patients with batroxobin (P < 0.05). Two patients with batroxobin and two patients without batroxobin developed hemorrhagic stroke during follow-up. There were five deaths (9.6%) in the batroxobin group, and seven deaths (11.7%) in the nonbatroxobin group during follow-up (P > 0.05). Intermittent intravenous injection of batroxobin can efficiently reduce the risk for stroke/TIA recurrence in patients with concomitant hyperfibrinogenemia.  相似文献   
29.
金军  付伟  钟声 《中国骨伤》2007,20(12):821-822
目的分别应用三针锁针加压器外固定和空心拉力钉内固定疗法治疗股骨颈骨折,探讨股骨颈骨折最佳治疗方法.方法应用三针锁针加压器外固定治疗股骨颈骨折63例,其中男24例,女39例;年龄55~89岁,平均(64.5±3.2)岁;Garderl Ⅰ型2例,Ⅱ型15例,Ⅲ型38例,Ⅳ型8例.应用空心拉力钉内固定治疗63例,其中男29例,女34例;年龄45~76岁,平均(62.2±2.9)岁;Garden Ⅰ型4例,Ⅱ型24例,Ⅲ型28例,Ⅳ型7例.对其疗效进行分析.结果126例除2例死亡外均得到随访.115例愈合,其中10例股骨头坏死.外固定组愈合58例,股骨头坏死4例,死亡1例;内固定组愈合57例,股骨头坏死6例,死亡1例.根据Harris功能评定标准评价疗效,外固定组62例中优24例,良26例,可8例,差4例,优良率80.65%;内固定组62例中优23例,良27例,可6例,差6例,优良率80.65%.Harris评分外固定组平均(80.40±1.21)分,内固定组平均(79.14±1.47)分,两组Harris评分比较差异无统计学意义(P>0.05).结论采用内外固定治疗股骨颈骨折疗效无明显差异,但外固定创伤小、费用低、可早期离床;而采用拉力钉内固定器医疗成本高,卧病时间相对较长,且需二次手术取内固定钉.  相似文献   
30.
甲状腺癌淋巴结微转移的研究   总被引:2,自引:0,他引:2  
目的:探讨MUC1检测在甲状腺癌淋巴结微转移的可靠性和敏感性。方法:对488例甲状腺疾病手术患者于术前24h用1%美兰1.0~2.0mL注射于甲状腺结节或周围腺体,术中显示蓝染淋巴结,采用RT-PCR法测定临床蓝染淋巴结中的MUC1。 结果:蓝染淋巴结显示率甲状腺癌为93%,良性病例为0。研究组80个蓝染淋巴结中发现有MUC1mRNA表达的为95%,与病理诊断率(86%)相比有提高(P<0.05);良性病变(阴性对照组)淋巴结均不存在MUC1mRNA的表达;阳性对照组的癌转移性淋巴结均存在MUC1mRNA的表达。结论:MUC1较病理检查敏感,PCR产物点杂交进一步证实MUC1作为PCR标志物有较好的可靠性。  相似文献   
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