法舒地尔对高血压大鼠勃起功能的影响

目的:探讨Rho激酶抑制剂法舒地尔对高血压大鼠勃起功能的影响及其机制。方法:12周龄雄性SD大鼠随机分成对照组(A组)、高血压组(B组)、法舒地尔治疗组(C组),建立高血压大鼠模型后,C组给予法舒地尔[30 mg/(kg.d)]腹腔注射,A组、B组给予等量生理盐水腹腔注射,术后10周测量大鼠阴茎海绵体内压/平均颈动脉压(ICPmax/MAP),Western印迹法测定ROCK1、ROCK2蛋白在阴茎海绵体的表达水平。结果:B组收缩压(mmHg)、ROCK1、ROCK2蛋白表达(190.39±5.07、0.048±0.002、0.143±0.011)较A组(124.81±4.01、0.036±0.001、0.101±0.011)显著增加(P<0.05),C组收缩压(mmHg)、ROCK1、ROCK2蛋白表达(182.03±4.32、0.044±0.001、0.126±0.007)较B组显著降低(P<0.05),B组ICPmax/MAP(36.82±5.47)较A组(59.99±5.69)显著降低(P<0.05),C组(51.1±5.63)较B组显著提高(P<0.05)。结论:法舒地尔可通过抑制RhoA/Rho激酶信号高表达及可能的降血压作用而改善高血压大鼠勃起功能。     

镰刀状肾实质切开对犬肾功能的影响

目的　探讨镰刀状肾实质切开对犬肾功能的影响。方法　将 1 8条成年犬分 3组 :实验组为镰刀状肾实质切开组 (A组 )、对照组为肾后唇中下 1 / 3肾实质切开组 (B组 )和无萎缩性肾实质切开组 (C组 )。观测 :术前 ,术后 1d、3d,1周、2周尿微量白蛋白 (ALB)、尿N 乙酰 β氨基葡萄糖酐酶 (NAG) ;术后 1周、1个月排泄性尿路造影 (IVU) ;术后 6月肾组织光镜和电镜结构。结果术后 1d、3d、1周、2周尿ALB和NAG值A组分别为 2 87.45± 8.2 3和 3 .45± 0 .2 8、32 7.87± 1 0 .98和 5 .2 5± 0 .48、468.36± 2 0 .66和 7.87± 0 .65、2 1 2 .87± 1 3 .65和 3 .0 1± 0 .1 7,与B、C两组比较 ,A组明显低于C组 (P <0 .0 1 ) ,A、B组间差异无显著性 (P >0 .0 5) ;术侧肾显影延缓时间A组 (1 35± 1 2 )s明显短于C组 (2 67± 2 8)s(P <0 .0 1 ) ,而与B组 (1 2 8± 1 5)差异无显著性 (P >0 .0 5) ;A、B组肾脏的病理改变明显轻于C组。结论　镰刀状肾实质切开对肾功能影响小 ,是治疗复杂性鹿角状肾结石的较理想术式     

心脏机械瓣置换后不同强度抗凝对病人凝血激活的影响

目的　探讨不同强度抗凝时 ,心脏机械瓣置换术后病人的凝血激活状态。方法　将 16 2例心脏机械瓣置换术后病人 ,根据抗凝强度 (INR)分成 4组 :A组 (<1 5 ) 2 5例 ;B组 (1 5～ <2 0 ) 4 4例 ;C组 (2 0～ <3 0 ) 6 1例 ;D组 (3 0～ <4 5 ) 32例。 2 0例正常成人为对照组。采用酶联免疫吸附法 (ELISA)测定各组血浆凝血酶原片段 1+2 (F1 + 2 )、D 二聚体浓度。结果　A、B、C、D和对照组F1 + 2 浓度分别为(2 4 8± 1 32 )、(1 2 3± 0 6 5 )、(0 81± 0 4 5 )、(0 73± 0 39)、(1 11± 0 35 )nmol L ;D 二聚体浓度分别为(0 4 5± 0 2 4 )、(0 30± 0 17)、(0 2 4± 0 10 )、(0 2 5± 0 11)、(0 2 1± 0 0 9)mg L。A组F1 + 2 和D -二聚体浓度均显著高于对照组 (P <0 0 1) ;B组F1 + 2 浓度与对照组无差异 (P >0 0 5 ) ,D 二聚体浓度显著高于对照组 (P <0 0 5 ) ;C、D组F1 + 2 浓度均显著低于对照组 (P <0 0 5 ) ,但C、D两组间差异无显著性 (P >0 0 5 ) ;C、D组D 二聚体浓度与对照组之间均差异无显著性 (P >0 0 5 )。结论　在INR 2 0～ 3 0的抗凝强度下 ,心脏机械瓣置换术后病人凝血激活受到明显抑制     

关节镜下同种异体组织重建膝关节前后交叉韧带的临床研究

目的　评价关节镜下同种异体组织重建膝关节前后交叉韧带 (ACL ,PCL)的疗效。方法　回顾调查了 36例孤立性交叉韧带损伤病人 ,将其分为 2组 ,A组 :ACL损伤 2 8例 ;B组 :PCL损伤 8例。分别应用同种异体B -PT -B、半腱与股薄肌腱、胫后肌腱、跟腱 -骨和四头肌腱 -骨重建 ,平均随访 2 1 5个月。结果　Lysholm评分 :A组术前平均 6 3± 5 6 ;术后 90±5 5 ;B组术前平均 6 1± 7 6 ,术后 88± 6 0 ;两组手术前后差异显著 (P <0 0 1) ;IKDC评分 :A组A级 2例 (7% ) ,B级 16例 (5 7% ) ,C级 8例 (2 9% ) ,D级 2例 (7% ) ;B组A级 1例 (12 5 % ) ,B级 3例 (37 5 % ) ,C级 3例 (37 5 % ) ,D级 1例 (12 5 % )。KT2 0 0 0测定 :A组由术前胫骨前移平均 11 90± 0 2 7mm减少至术后 4 30± 1 4 2mm ;B组胫骨后移由术前平均 10 5± 2 5mm减少至术后 5 9± 1 5mm ,两组手术前后有显著差异 (P <0 0 1)。术后健患侧比较 :A组平均 2 3± 0 9mm ;B组 2 7± 1 3mm ;健患差异 :A组 <3mm2 3/ 2 8例 (82 % ) ,>5mm 3例 (11% ) ;B组 <3mm 5 / 8例 (6 2 5 % ) ,>5mm 2例 (2 5 % )。前后抽屉试验大部分平均恢复 1°以上 ,并呈现明显的硬终点。术后ROM ,A组 :正常 2 6 / 2 8例 (93% ) ,接近正常 2 / 2 8例 (7% ) ;B组 :     

大鼠肝脏冷缺血再灌注损伤后B7表达的研究

摘要：目的:探讨B7-1和B7-2在大鼠肝脏冷缺血再灌注损伤时的表达及其免疫学意义。方法:将30只大鼠随机分为3组：A组为假手术组(对照组)；B组为冷缺血20min再灌注24h组；C组为冷缺血30min再灌注24h组。分别取各组之肝脏，采用实时反转录聚合酶链反应(RT-PCR)检测肝组织中B7-1和B7-2mRNA的表达。结果:B7-1mRNA在B，C组表达为0.529±0.089和0.618±0.074，均较A组(0.131±0.012)明显增高(P<0.01)。B7-2mRNA在B，C组表达为0.474±0.132和0.682±0.095，均较A组(0.163±0.054)明显增高(P<0.01)。并且B7-1和B7-2在C组表达明显高于B组(P<0.05)。结论:冷缺血再灌注时肝脏B7-1和B7-2表达上调，增加了肝脏的免疫原性。     

血管襻骨膜内腓骨组合移植修复负重长段骨缺损的实验研究

目的　研究血管袢骨膜内腓骨组合移植修复负重长段粗骨缺损临床应用可行性。　方法　健康新西兰大白兔 72 只,随机分为 3 组。A组:单腓移植组;B组:骨膜外双腓骨组合移植组;C组:骨膜内双腓骨组合移植组。制成胫骨中上段骨缺损 10 0 mm,采用 3 种手术方式,术后 2、4、8、12、16周分别拍X线片及测定血清碱性磷酸酶、骨钙素、骨密度及组织学、生物力学检查。　结果　X线结果显示,C组较A、B组骨痂增加明显,骨小梁排列整齐,移植腓骨明显增粗。术后 4 周血清 ALP:A组 (91 .6±9. 2)、B组 (11.4 9±5 .1)、C组 (136 6±3 9);血清 BGP:A组(3. 90±1. 02)、B组 (4. 69±0. 58)、C组 (5 .84±0. 98);骨密度:A组 (0. 179±0 .03)、B组(0. 286±0 .04)、C组 (0. 301±0. 07),C组较A组、B组差异均有统计学意义(P<0 01)。组织学检查C组较A、B组骨痂形成早、成熟早,骨小梁排列整齐,两腓骨形成一体,髓腔再通。成骨量:A组 (398±4 0)、B组 (41. 7±2 .3)、C组(49. 2±5 .7),C组与A、B组比较,P<0. 05。生物力学测试,移植骨平均最大载荷、最大扭距及剪切应力,C组均大于A、B组。　结论　血管袢骨膜内腓骨组合移植是治疗负重长段粗骨缺损较为理想的手术方式。     

雄激素对大鼠阴茎海绵体平滑肌中兰尼碱受体1和电压门控钙离子通道1.3表达的影响研究

目的:研究兰尼碱受体1(RyR1)和电压门控钙离子通道1.3(CaV1.3)在去势大鼠阴茎海绵体平滑肌的表达,探讨其在去势后勃起功能障碍发生中的作用。方法:40只8周龄雄性SD大鼠随机均分成:假手术2周组(A组),假手术4周组(B组),去势2周组(C组),去势4周组(D组)。术后实验各组检测血清睾酮(T)水平,免疫组化及RT-PCR技术检测RyR1和CaV1.3在大鼠阴茎海绵体平滑肌中的表达。结果:血清T水平C组[(15.97±5.67)nmol/L]和D组[(2.03±1.57)nmol/L]分别较A组[(90.54±20.13)nmol/L]和B组[(120.35±30.32)nmol/L]显著下降(P<0.05)。RyR1、CaV1.3在各组大鼠阴茎海绵体平滑肌中均有表达,RyR1 mRNA相对表达量灰度比值C组(0.51±0.24)和D组(0.33±0.15)分别较A组(1.53±0.25)和B组(1.37±0.23)显著降低(P<0.05);CaV1.3 mRNA相对表达量灰度比值C组(0.50±0.12)和D组(0.32±0.07)分别较A组(1.33±0.05)和B组(1.25±0.03)显著降低(P<0.05)。RyR1蛋白积分光密度值(IA)C组(120.36±25.78)和D组(67.39±30.54)分别较A组(300.96±135.12)和B组(330.38±128.59)显著降低(P<0.05);CaV1.3蛋白IA C组(103.37±39.52)和D组(67.56±20.15)分别较A组(298.68±126.35)和B组(327.35±117.37)显著降低(P<0.05)。雄激素水平与RyR1、CaV1.3在阴茎海绵体平滑肌中的表达水平具有正相关性。结论:雄激素可能通过RyR1、CaV1.3的表达调控阴茎勃起功能。     

参附注射液对兔脊髓缺血损伤保护作用的量效关系研究

目的探讨参附注射液对脊髓缺血性损伤保护作用的剂量效应关系。方法24只雄性新西兰大白兔,随机分为四组A组(n=6),单纯缺血再灌注组,B组(n=6)、C组(n=6)和D组(n=6)分别于缺血前30min内持续恒速静脉输入参附注射液5ml·kg-1、10ml·kg-1、20ml·kg-1;采用肾下主动脉阻断法造成脊髓缺血(20min);术后观察神经功能变化并记录再灌注1h、4h、8h、12h、24h和48h神经功能评分,再灌注48h处死动物后取脊髓(L5～7)标本行病理学观察。结果术后神经功能评分除再灌注1hD组与A组之间无显著性差异,其余各时间点B组、C组和D组均明显高于A组(P<0．05),B组、C组和D组间则无显著性差异(P>0．05),且48h时各组神经功能评分分别为A组0．5±0．8、B组3．2±0．9(P<0．001)、C组3．0±1．0,(P<0．001)和D组2．7±0．8(P<0．05);再灌注48h脊髓前角正常运动神经元计数B组(78±25,P<0．001)、C组(41±23,P<0．05)和D组(42±27,P<0．05)均高于A(8±7)组,B组与C组、D组间亦有显著性差异(P<0．05)。结论参附注射液对脊髓缺血性损伤有保护作用,但无明显剂量效应关系。     

可塑形组织工程骨修复兔颅骨缺损的组织学及力学研究

目的探讨用藻酸钙凝胶、成骨细胞和骨粉复合构建可塑形组织工程骨修复兔颅骨缺损后,体内成骨的组织学及生物力学特征。方法28只日本大耳白兔,随机分为A组(16只)、B组(8只)和C组(4只)。制备兔颅骨左右两侧直径1cm的骨膜-颅骨全层缺损,左侧用藻酸钙凝胶-成骨细胞-骨粉填补修复为A1组(n=16);右侧用藻酸钙凝胶-骨粉填补修复为A2组(n=16);B组骨缺损不作处理,为空白对照组(n=16);C组为正常组。术后6周和12周时,行大体观察及组织学观察;12周时行生物力学测试。结果术后6、12周时,A1组:颅骨缺损基本被硬组织所修复,镜下见材料已大部分被骨组织替代,成骨面积为40.92%±19.36%;A2组:材料部分被骨组织替代,成骨面积为18.51%±6.01%;B组:颅骨缺损边缘可见硬组织形成,镜下见修复组织以致密纤维组织为主,成骨面积为12.72%±9.46%。术后12周,生物力学测试修复组织能耐受的最大压力载荷,A1组37.33±2.95N;A2组30.59±4.65N;B组29.5±2.05N;C组41.55±2.52N;A1组明显大于A2组和B组(P<0.05)。最大载荷时应变位移,A1组1.05±0.20mm;A2组1.35±0.44mm;B组1.57±0.31mm;C组0.95±0.17mm;A1组小于B组(P<0.05)。载荷/应变比值,A1组35.82±6.48N/mm;A2组24.95±12.40N/mm;B组19.90±5.47N/mm;C组47.57±11.22N/mm;A1组大于B组(P<     

0.33％等比重罗哌卡因蛛网膜下腔阻滞在高龄半髋关节置换术中的应用研究

目的 评价0.33％等比重罗哌卡因蛛网膜下腔阻滞在高龄半髋关节置换术中应用的安全性和有效性. 方法 年龄≥70岁,ASA分级Ⅱ、Ⅲ级,行半髋关节置换术的患者150例,按随机数字表法分为A组、B组、C组(每组50例).所有患者均采用健侧卧位,穿刺间隙为L3～L4椎间隙,用脑脊液将1％盐酸罗哌卡因注射液稀释成0.33％(1 ml罗哌卡因+2 ml脑脊液),A组、B组、C组分别给予2.2、2.0、1.8 ml.于麻醉前(T0),蛛网膜下腔注药后5 min (T1)、10 min(T2)和15 min(T3),手术开始时(T4),手术开始后30 min(T5),术毕(T6)时点,记录MAP、HR和感觉阻滞平面高度,并记录麻醉诱导时间、手术时间、术中出血量、尿量和输液量以及术中、术后相关并发症. 结果 蛛网膜下腔阻滞有效率和阻滞效果A组明显优于B组、C组,且B组优于C组(P＜0.05).麻醉诱导时间A组[(15.6±1.4) min]明显短于B组[(19.5±6.3)min]、C组[(26.6±7.1) min],且B组短于C组(P＜0.05).HR在A组T1～T6时[(80±12)、(80±11)、(78±10)、(77±10)、(77±10)、(77±10)次/min]和B组T1～T2时[(77±8)、(77±7)次/min]较各组To时[(71±11)、(73±9)次/min]明显增快(P＜0.05);MAP在A组T1、T2时[(96±8)、(98±8) mmHg(1 mmHg=0.133 kPa)]、B和C组T4～T6时[(100±8)、(100±8)、(100±8) mmHg和(96±8)、(98±7)、(99±8) mmHg]较各组To时[(104±8)、(104±8)、(103±8) mmHg]均明显降低(P＜0.05),且C组T4～T6时较T3时也明显降低(P＜0.05).T1～T3时A组感觉阻滞平面明显高于B组和C组,且B组高于C组(P＜0.05);在T4～T6时A组和B组明显高于C组(P＜0.05);与T3比较,A组感觉阻滞平面在T6时明显降低(P＜0.05);B组、C组感觉阻滞平面在T4～T6时明显升高(P＜0.05).术中低血压和恶心呕吐的发生率A组、B组均明显低于C组(P＜0.05),而A组和B组比较,差异均无统计学意义(P＞o.05). 结论 0.33％等比重罗哌卡因蛛网膜下腔阻滞应用于高龄半髋关节置换术中具有安全性和有效性.     

Metallurgical differentiation of cobalt-chromium alloys for implants

BACKGROUND: Cobalt Chromium alloys are used in cemented total hip or knee arthroplasty as well as in metal-on-metal bearings in total hip arthroplasty. An increasing number of publications report about (allergic) reactions to wear particles of Cobalt Chromium alloys. Reactions to nickel are more frequent in comparison to Cobalt or Chromium particles. It is well known that different kinds of Cobalt Chromium alloys contain different amounts of alloying elements; nevertheless. The aim of the current work was to compare the different Cobalt Chromium alloys according to ASTM F or ISO standards in respect to the different alloying elements. MATERIAL AND METHODS: Co28Cr6Mo casting alloys according to ASTM F 75 or ISO 5832-4 as well as forging alloy types according to ASTM F 799 and ISO 5832 such as Co20Cr15W10Ni, Co35Ni20Cr, Fe40Co20Cr10Ni, Co20Cr20Ni, and Co28Cr6Mo were analyzed in respect to their element content of Co, Cr, Ni, Mo, Fe, W, and Mn. RESULTS: In 1935 the Cobalt based alloy "Vitallium" Co30Cr5Mo basically used in the aircraft industry was introduced into medicine. The chemical composition of this alloy based on Cobalt showed 30 wt.% Chromium and 5 wt.% Molybdenum. The differentiation using alloy names showed no Nickel information in single alloy names. CONCLUSION: The information given about different alloys can lead to an unprecise evaluation of histopathological findings in respect to alloys or alloying constituents. Therefore, implant manufacturers should give the exact information about the alloys used and adhere to European law, Euronorm 93/42/EWG.     

Cobalt-base alloys used in bone surgery

Cobalt-base alloys may be generally described as non magnetic, wear, corrosion and heat-resistant (high strength even at elevated temperature). Many properties of the alloy originate from the crystallographic nature of cobalt, the solid-solution-strengthening effect of chromium and molybdenum, the formation of extremely hard carbides and the corrosion resistance imparted by chromium. Cobalt-base alloys are difficult to fabricate which is why their use has been limited, but continuous work led to the development of specialized casting methods. Due to its excellent resistance to degradation in the oral environment, the first medical use of cobalt-base alloys was in the cast of dental implants. Various in vitro and in vivo tests have shown that the alloys are biocompatible and suitable for use as surgical implants. Today, the use of Co alloys for surgical applications is mainly related to orthopaedic prostheses for the knee, shoulder and hip as well as to fracture fixation devices. Joint endoprostheses are typical long-term implants and the applied implant material must therefore meet extremely high requirements with regard to biocompatibility with the surrounding body tissue material and corrosion resistance to body fluids.     

Titanium alloys for fracture fixation implants

This paper is intended to provide an overview of the composition, mechanical properties, biocompatibility, and clinical applications for titanium alloys that are used for fracture fixation implants. A new class of titanium implant alloys has emerged in recent years that exhibits a beta microstructure and a unique combination of mechanical properties. Important information regarding notch sensitivity testing and clinical significance is also discussed. Attributes such as stress corrosion cracking resistance, fatigue strength, and wear characteristics are also essential for specific clinical applications, but are beyond the scope of this presentation.     

Systemic effects of implanted prostheses made of cobalt-chromium alloys

Summary Systemic effects of Co-Cr alloy/polyethylene hip joint prostheses were investigated using instrumental neutron activation to determine the concentrations of up to 16 elements. First, in a prospective study whole blood and serum taken from 10 patients from 1 day before to 90 days after implantation were analyzed. Secondly, in a retrospective study whole blood and serum from 23 patients who had had prostheses in place for up to 18 years were analyzed. For comparison, normal trace element levels in humans were determined by analyzing whole blood and serum from 21 patients. Finally, various tissues and organs from two deceased implant patients were analyzed and compared with normal concentrations obtained from the analysis of five normal patients without implants. In agreement with other recent investigations, our analyses of normal serum, whole blood, tissues, and organs show that most previously defined normal trace element concentrations were too high, chiefly owing to contamination and insufficient blanks. A detailed discussion shows that for many elements the ranges of normal concentrations have to be revised. This conclusion is of particular importance with respect to the sometimes conflicting earlier reports of systemic effects of metal prostheses. In the work reported here, both the prospective and the retrospective investigations of serum and whole blood showed massive Co enrichments as a consequence of implant corrosion. The data show a wide range of individual burdening, ranging from practically no effect to the most extreme values. The analyses of tissues from the vicinity of the implants in the two deceased implant patients showed strong local effects of Co, Cr, Zr, and Hf, the latter two elements originating from the X-ray contrast media in the bone cement. The analyses of organs revealed significant Co and Cr enrichment in several tissues and organs. Consequently, it can be seen that implant corrosion is not an occurrence of merely local significance, but one that affects the trace element status of the entire organism.This work was supported by the Deutsche Forschungsgemeinschaft, Bonn, Federal Republic of Germany     

可降解镁合金腐蚀及生物相容性

镁合金有良好的生物相容性和可降解性,有潜力成为骨科临时性植入材料,为创伤或病变组织愈合期间提供暂时的机械支持.新型可降解镁合金生物材料已引起高度关注.该文就镬合金腐蚀、腐蚀影响因素及生物相容性等作一综述.     

Rough titanium alloys regulate osteoblast production of angiogenic factors

Background contextPolyether-ether-ketone (PEEK) and titanium-aluminum-vanadium (titanium alloy) are used frequently in lumbar spine interbody fusion. Osteoblasts cultured on microstructured titanium generate an environment characterized by increased angiogenic factors and factors that inhibit osteoclast activity mediated by integrin α2β1 signaling. It is not known if this is also true of osteoblasts on titanium alloy or PEEK.PurposeThe purpose of this study was to determine if osteoblasts generate an environment that supports angiogenesis and reduces osteoclastic activity when grown on smooth titanium alloy, rough titanium alloy, or PEEK.Study designThis in vitro study compared angiogenic factor production and integrin gene expression of human osteoblast-like MG63 cells cultured on PEEK or titanium-aluminum-vanadium (titanium alloy).MethodsMG63 cells were grown on PEEK, smooth titanium alloy, or rough titanium alloy. Osteogenic microenvironment was characterized by secretion of osteoprotegerin and transforming growth factor beta-1 (TGF-β1), which inhibit osteoclast activity and angiogenic factors including vascular endothelial growth factor A (VEGF-A), fibroblast growth factor 2 (FGF-2), and angiopoietin-1 (ANG-1). Expression of integrins, transmembrane extracellular matrix recognition proteins, was measured by real-time polymerase chain reaction.ResultsCulture on titanium alloy stimulated osteoprotegerin, TGF-β1, VEGF-A, FGF-2, and angiopoietin-1 production, and levels were greater on rough titanium alloy than on smooth titanium alloy. All factors measured were significantly lower on PEEK than on smooth or rough titanium alloy. Culture on titanium alloy stimulated expression of messenger RNA for integrins that recognize Type I collagen in comparison with PEEK.ConclusionsRough titanium alloy stimulated cells to create an osteogenic-angiogenic microenvironment. The osteogenic-angiogenic responses to titanium alloy were greater than PEEK and greater on rough titanium alloy than on smooth titanium alloy. Surface features regulated expression of integrins important in collagen recognition. These factors may increase bone formation, enhance integration, and improve implant stability in interbody spinal fusions.     

磷铜-纯银双极电凝镊的实验研究

神经外科手术在使用双极电凝镊电灼出血血管时,烧焦的组织往往会粘连于镊尖上,而且粘上的焦痂不易用湿纱布擦干净,由此可能导致出血血管电凝不足或电凝过度[1].为了尽量减少焦痂在镊尖上形成,国内外一些学者先后对双极电凝器[1-3]、双极电凝镊[4-6]及电凝镊与血管接触点之间电阻大小与粘连程度的关系[7,8],进行过一系列基础和临床研究,并取得了一定成效.目前国内外使用的双极电凝镊基本上是用不锈钢做镊柄,银铜合金或钛合金做镊尖[4],即所谓的不锈钢-合金双极电凝镊.由于名牌产品德国蛇牌双极电凝镊的镊柄由不锈钢制成,镊尖由含30%银的合金制成,所以笔者选用蛇牌电凝镊作为试验的对照(以下简称蛇牌镊).尚未见用纯银制作镊尖的报道.因此,笔者自行设计和制作了以富有弹性的磷铜做镊柄、纯银做镊尖的磷铜-纯银双极电凝镊(以下简称纯银镊).现报道如下.     

壳聚糖表面改性钛合金材料的研究进展

钛合金材料生物性能良好,是骨科常用的内植入材料,但其骨整合性及抗菌性能较差,需进行表面改性以弥补其不足之处。壳聚糖具有良好的生物相容性及成膜性,且可作为载体将目标药物引入钛合金表面,可有效改善钛合金材料的生物学性能,增加其使用范围。本文对近几年壳聚糖表面改性钛合金材料的相关研究进行归纳总结,从壳聚糖涂层改性的方式、钛合金材料成骨性及抗菌性的改善3个方面展开论述,以期为钛合金材料涂层改性在临床中的应用提供指导依据。     

In vitro vs in vivo corrosion analyses of two alloys

The in vitro and in vivo corrosion characteristics of two alloys, cast Co-Cr-Mo (ASTM F75) and wrought Ni-Cr-Mo, were evaluated using electro-chemical corrosion analysis. Two in vitro electrolytic solutions were utilized, an isotonic saline solution consisting of 0.9 w/o NaCl in distilled water and an isotonic saline solution with 10 v/o sterile calf serum. The in vivo environment was created by implanting cylindrically shaped specimens of each alloy into the back muscles of New Zealand white rabbits. Cyclic anodic and cathodic polarization curves were generated for the three test conditions and subsequently were compared. Anodic curves conducted using the isotonic saline and isotonic saline plus serum electrolyte solutions were very similar to the anodic curves generated for the implanted alloy specimens for both alloys. The corrosion rates predicted from the in vitro and in vivo cathodic polarization curves were not statistically different for the three test conditions. Overall, the corrosion data generated using the in vitro environmental conditions adequately predicted the in vivo corrosion behavior of the cast Co-Cr-Mo and wrought Ni-Cr-Mo alloys.