皮质骨嵌压钉在前交叉韧带重建中的生物力学研究

目的探讨胭绳肌腱移植重建前交叉韧带（ACL）胫骨端皮质骨嵌压钉的生物力学。方法新鲜冷冻膝关节标本21具（北京市解剖学会提供）,采用四股胭绳肌腱移植重建ACL,胫骨端分别用自制皮质骨嵌压钉（n=7）、可吸收界面螺钉（n=7）和Intrafix（n=7）固定,测试最大载荷、100N和400N位移、抗拉刚度、失败模式等数据并进行统计学分析。结果以上指标在皮质骨嵌压钉组和可吸收界面螺钉组无统计学差异。皮质骨嵌压钉组的最大拔出载荷及抗拉刚度〈Intrafix固定组（P〈0．05）,100N位移、400N位移〉Intrafix固定组（P〈0．05）。结论自制皮质骨嵌压钉的最大拔出载荷、100N位移、400N位移以及抗拉刚度均与可吸收界面螺钉相近,可以满足ACL重建固定肌腱的需要。     

注射式磷酸钙骨水泥加固颈椎前路螺钉的生物力学研究

目的:评价注射式磷酸钙骨水泥(Calcium phosphate cement,CPC)在骨质疏松时对颈椎前路单皮质骨螺钉的强化作用.方法:4具新鲜老年男性尸体C4～C6共12个椎体,随机分为A、B 2组,每组6个.在椎体前方中线两侧8 mm处向中线倾斜5°攻丝锥导孔,钻出钉道备用,不穿透椎体后方骨皮质.A组:取椎体一侧置入螺钉作为对照组,在材料实验机上行轴向拔出鲻实验,拔出速率为5 mm/min.螺钉拔出后用CPC修复钉道作为修复组,另一侧以CPC填充后置入螺钉作为强化组,37℃下放置24 h后再行轴向拔出试验.B组:取椎体一侧置入螺钉作为对照组,另一侧以CPC填充后置入螺钉作为强化组行周期抗屈实验.周期抗屈实验后测定其最大抗剪切力.结果:对照组拔出力(106 47)N,修复组(154±67)N,强化组(191±79)N,修复组、强化组的拔出力均明显高于对照组(P＜0.05);强化组在相同载荷下产生的位移明显小于对照组(P＜0.05);对照组最大抗剪切力为(87±39)N,强化组为(149±63)N,强化组的最大抗剪切力明显强于对照组,差异有统计学意义(P＜0.05).结论:CPC能显著提高疏松骨质中颈椎前路单皮质骨螺钉的轴向拔出力及抗剪切能力,提示CPC有利于加固颈椎前路螺钉,对骨质疏松症患者可进行牢固内固定.     

磷酸钙骨水泥强化椎体钉固定的生物力学影响

目的:磷酸钙骨水泥(CPC)强化穿透单侧椎体皮质椎体钉固定的生物力学影响.方法:选用新鲜成人尸体标本16个,实验组磷酸钙骨水泥强化后椎体钉穿透单侧椎体皮质固定;对照组为无骨水泥强化,螺钉穿透双侧椎体皮质固定.应用螺钉拔出实验,记录螺钉最大拔出力并观察椎体破坏形态.结果:拉力值 CPC组(1393.33±189.37)、对照组(957.42±71.34)差异有显著性,P＜0.01.对照组椎体中螺钉抽出占75%(6/8),螺钉入口处皮质破损占25%(2/8).CPC强化椎体中螺钉入口处皮质破损占87.5% (7/8),螺钉抽出占12.5%(1/8)..结论:CPC强化椎体钉后固定效果更好,增加手术安全性.     

后凸成形骨水泥强化技术在骶骨钉翻修中的生物力学作用

 【目的】 评价后凸成形骨水泥(PMMA)强化技术对骨质疏松情况下骶骨钉固定强度的生物力学影响,为骶骨钉翻修选择坚强的补救技术提供依据&#65377;【方法】 11具新鲜骶骨标本用于实验,双能X线吸收法(DEXA)评价骨密度&#65377;在同一骶骨上,依次建立非PMMA强化和PMMA强化骶骨钉的固定模型如下,A组:单皮质椎弓根钉;B组:双皮质椎弓根钉;C组:传统PMMA强化单皮质椎弓根钉;D组:后凸成形PMMA强化椎弓根钉;E组:后凸成形PMMA强化侧翼钉&#65377;在MTS试验机上对五种骶骨钉依次进行轴向拔出测试,记录最大承受拔出力并比较&#65377;【结果】 11具标本的平均骨密度为(0.71 ± 0.08) g/cm2&#65377;A组的螺钉拔出力(508 N)显著低于其它4种固定组(P < 0.05)&#65377;B组的螺钉拔出力(685 N)与E组(702 N)无显著差异(P > 0.05),但是,两者的拔出力均显著低于C和D组(P < 0.05)&#65377;重要的是,D组(986 N)的拔出力显著高于C组(846 N)&#65377;【结论】 在骨质疏松患者的骶骨固定中,双皮质骶骨椎弓根钉较单皮质具有显著的力学优势&#65377;骶骨椎弓根钉一旦发生松动,传统的和后凸成形PMMA强化技术均可成为补救手段,并且后凸成形PMMA强化骶骨椎弓根钉可获得最坚强的锚定&#65377;     

同种异体皮质骨锚钉修复肩袖损伤的动物实验

目的探讨使用同种异体皮质骨锚钉修复肩袖损伤在不同时间段锚钉和骨道壁之间的愈合情况。方法使用深低温冷冻（-80℃）的成年羊胫骨皮质骨制成肩袖缝合锚钉,试验动物选用6只山羊。术中直接取肩关节正中切口,解剖分离出冈上肌腱,于止点处锐性切断,使用锉刀在肌腱止点原附着点进行磨挫直至出现新鲜骨面。将皮质骨锚钉缓慢植入预钻孔内,使用锚钉所带缝线将离断的冈上肌腱组织缝合至新鲜骨面。分别在术后第4、8、12周三个时间点取材,进行放射学、大体形态和组织切片检查,观察冈上肌腱的腱-骨愈合情况及骨锚钉的组织学转归。结果术后第12周固定处冈上肌腱与骨面形成牢固的腱骨愈合,放射学显示骨锚钉在各个时间点逐步与周围骨质融合。HE染色检查显示在第12周时骨锚钉与周围骨质完全融合。结论使用同种异体皮质骨锚钉固定修复肩袖损伤可达到牢固的腱-骨愈合目的,术后皮质骨锚钉与周围骨质融合,没有出现锚钉脱出、骨缺损等并发症。     

改良空心钉系统治疗 Pauwels Ⅲ型儿童股骨颈骨折的生物力学分析

目的 探讨改良配套可锁定实心栓的空心钉系统治疗Pauwels Ⅲ型儿童股骨颈骨折的生物力学性能。方法 采用人工合成的生物骨标本40 个,进行编号后随机分成A 组、B 组、C 组、D 组（n=10）,制成Pauwels Ⅲ型儿童股骨颈骨折模型（Pauwels 70°）,解剖复位骨折标本。A 组采用2 枚传统空心钉固定、B 组采用2 枚改良配套可锁定实心栓的空心钉系统固定、C 组采用3 枚传统空心钉固定、D 组采用3 枚改良配套可锁定实心栓的空心钉系统固定,固定后进行生物力学测试,比较四组的轴向压缩刚度、循环载荷位移变化、极限压缩载荷、极限测试刚度。结果 四组骨折内固定模型之间轴向压缩刚度、循环载荷位移变化、极限压缩载荷、极限测试刚度比较,差异有统计学意义（P＜0.05）。其中轴向压缩刚度：A 组（706.30±20.86）N/mm＜B 组（821.00±24.01）N/mm＜C 组（1197.90±79.38）N/mm＜D 组（1381.80±99.88）N/mm;循环载荷位移：A 组（0.93±0.09）mm＞B 组（0.74±0.05）mm＞C 组（0.45±0.04）mm＞D 组（0.35±0.03）mm;极限压缩载荷：A 组（1517.80±39.30）N＜B 组（1840.90±47.64）N＜C 组（3252.10±71.02）N＜D 组（3859.90±83.20）N;极限测试刚度：A 组（912.50±30.35）N/mm＜B 组（1010.80±45.56）N/mm＜C 组（1421.20±72.94）N/mm＜D 组（1525.50±127.61）N/mm。结论 改良配套可锁定实心栓的空心钉系统治疗PauwelsⅢ型儿童股骨颈骨折比传统空心钉具有更好的静态稳定和动态稳定,生物力学性能更好,值得临床推广使用。     

远端一枚或两枚锁钉对胫骨髓内钉力学性能影响的对比研究

目的 研究髓内钉远端锁钉数目对胫骨加锁髓内钉整体力学性能是否有影响.方法 实验共选用20根国产钛合金制造的9mm胫骨加锁髓内钉.将所有髓内钉随机分成两组,即远端安装单枚锁钉的单锁钉组,和远端安装2枚锁钉的双锁钉组.每组中各随机选用5根分别在万能力学实验机上进行压缩和扭转力学测试.测试所用的模型为根据国内外实验结果自行研究的不锈钢模型.结果 在压缩实验中,单钉组平均最大压缩载荷为1 850N,双钉组的平均最大载荷为2150N,双钉组抗压缩能力显著高于单钉组(P<0.05).在扭转实验中,单钉组平均最大扭矩、扭角分别为55.54N·m和57.36°,双钉组分别为55.78N·m和58.28°,两组差异无统计学意义(P>0.05).结论 胫骨髓内钉远端用单枚锁钉时其整体力学性质能满足临床要求.对于较严重的骨折类型还是推荐安装两枚远端锁钉.本实验采用的力学测量模型方便实用且经济易得,尤其适于髓内钉的力学对比研究.     

传统与改良皮质骨轨迹置钉技术的生物力学性能比较

目的 采用有限元方法比较传统和改良皮质骨轨迹置钉技术的生物力学性能。方法 选取2019年11月新疆医科大学解剖实验室骨质疏松标本4具,平均年龄(70.5±6.5)岁,男性2名,女性2名,骨密度T值均<-2.5 SD。使用Mimics和Abaqus6.9建立L4椎体模型,传统皮质骨轨迹置钉技术选用螺钉直径为5.0 mm、长度为35 mm,改良皮质骨轨迹置钉技术选用直径为5.0 mm、长度为40 mm的螺钉进行置钉。为消除椎体骨质对力学性能的影响,在同一椎体的两侧椎弓根分别插入两种不同技术要求的螺钉,采用有限元方法测定两种螺钉的轴向抗拔出力,上下左右载荷情况下螺钉稳定性及前屈,后伸,轴向及侧屈旋转工况下椎体稳定性并比较其固定性能。结果 改良皮质骨轨迹置钉技术组的拔出力(1 822±83) N显著大于传统皮质骨轨迹置钉技术组拔出力(1 624±44) N,差异有统计学意义(P<0.05);改良皮质骨轨迹置钉技术组在受到上、下、右侧应力时载荷位移比明显大于传统皮质骨轨迹置钉技术组,差异有统计学意义(P=0.007;P=0.031;P=0.047);两种技术在左侧应力时载荷位移比差异...     

人体颈椎椎弓根钉与侧块钉轴向和切线方向生物力学研究以及与椎体骨密度相关性分析

目的　研究中下颈椎椎弓根钉和侧块钉的固定强度与骨密度的相关性。方法　解离C3 ～C7骨块 12 0个随机分为两组 ,测量每个椎体骨的松质骨密度 ,同一节段椎体随机配对置入椎弓根和侧块螺钉 ,在位移控制下分别测量位移控制下的平均最大拔出阻力和压力控制下的切向弹性与永久位移。结果　椎弓根钉的轴向平均最大拔出阻力明显高于侧块钉 ,切向弹性和固定位移则刚好相反 (均P <0 .0 1) ,在椎体松质骨密度 <12 0mgHA/ml时椎弓根钉和侧块钉的轴向拔出阻力与其呈显著正相关 (P <0 .0 1) ,骨密度 >12 0mg/ml HA时二者无相关性 ,而切线方向的永久位移和弹性位移与骨密度始终呈负相关。结论　椎弓根钉内固定较侧块钉具有更为优越的生物力学强度 ,二者与椎体松质骨密度有显著相关性。     

空心螺钉与哈勃钉经皮内固定Sanders Ⅱ型跟骨骨折的生物力学比较

目的 比较空心螺钉与哈勃钉经皮内固定Sanders Ⅱ型跟骨骨折的生物力学特性.方法 选取16足完整小腿新鲜足标本制作SandersⅡ型跟骨骨折模型,8例采用哈勃钉经皮内固定(观察组),8例采用空心螺钉经皮内固定(对照组).两组进行循环分级加载力学测试及屈服试验,记录不可逆位移、最大位移、弹性位移、最大负荷及最终位移.结果20～200 N负荷经1 000次循环后,最大位移及弹性位移观察组要显著低于对照组(均P＜0.05);20～700N负荷加载力学测试1000循环后,观察组不可逆位移、最大位移及弹性位移均要小于对照组(均P＜ 0.05).观察组最大负荷为明显大于对照组(P＜0.05).结论 哈勃钉经皮内固定Sanders Ⅱ型跟骨骨折符合足部的力学结构,稳定性好,固定强度大,能够很好的维持骨折对位.     

Value of D-Dimers in patients with acute aortic dissection

Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P ＜ 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (＞0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P ＜0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P ＜ 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.     

Research of combined liver-kidney transplantation model in rats

Objective： To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods： SD rats served as both donors and recipients. 4℃ sodium lactate Ringer＇s was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava （IVC） inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results： Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion： This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.     

BLOOD PRESSURE CHANGE WITH AGE IN SALT-SENSITIVE TEENAGERS

Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P＜ 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P＜ 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.     

安心颗粒对急诊经皮冠状动脉介入术后生活质量影响的研究

目的：评价使用安心颗粒对急诊经皮冠状动脉介入术（PPCI）术后生活质量的影响.方法：将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组（术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次）和对照组（仅接受基础药物治疗）.所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表（MIDAS）、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果：入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异（P＞0.05）;出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低（P＜0.05）;组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低（P＜0.05）.两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血（P＞0.05）.两组发生轻度血小板减少症的患者数比较无差异（P＞0.05）.结论：PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.     

The comparative studies of the influences of Urapidil and Nicardipine on sino-atrial node function, atrio-ventricular node function and hemodynamics

Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P＜0.01);the MAP decreased(P＜0.01)and the HR increased drastically(P＜0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.     

Expression of OPGmRNA and ODFmRNA in the patients of hip fracture due to osteoporosis

Objective：To investigate the gene expression of osteoprotegerin（OPG） and osteoclast differentiation factor（ODF） in the bone tissue of patients with hip fracture due to osteoporosis. Methods：OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers（over 50 years old） with hip fracture（Observer Group） and 30 cases of hip facture sufferers with no osteoporosis（Control group） were analyzed with the Semi-Quantitative RT-PCR method. Results：The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion：Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.     

The clinicopathological and immuohistochemical analysis of solid-pseudopapillary tumor of the pancreas： report of 9 cases

Objective：To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas（SPTP）. Methods：Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin（HE） staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results：Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin（9/9 cases）, AAT（9/9 cases）, NSE（9/9 cases）, ACT（7/9 cases）, CK20（2/9 cases）, CgA（1/9 cases）, S-100（3/gcases）, PR（4/gcases）, Syn（3/9 cases） and CD56（5/9cases）, negative in CEA and ER. Conclusion：SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.     

Dynamic Changes in Serum Estradiol and Progesterone levels in Patients of Premenstrual Syndrome with Adverse Flow of Liver-qi

Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.     

Real-time Three-dimensional Echocardiography in Assessment of Left Ventricular and Right Ventricular Volumes

Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.     

SCREENING FOR A 21-CHROMOSOME ABNORMALITY IN PREIMPLANTED EMBRYOS OF ELDERLY WOMEN

Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.