【摘要】：鈦合金止血夾是目前腹腔鏡手術(shù)臨床常用的止血夾,雖然對(duì)人體毒性較小,但其永久留存體內(nèi)會(huì)帶來(lái)離子溶出炎癥、干擾影像學(xué)診斷以及造成患者心理負(fù)擔(dān)等問(wèn)題�？晌崭叻肿又寡獖A可在體內(nèi)降解,但結(jié)構(gòu)較復(fù)雜,對(duì)操作者技術(shù)要求高,且成本較高。針對(duì)以上問(wèn)題,本文利用鎂及其合金良好的生物安全性、力學(xué)性能、特別是體內(nèi)可生物降解的特性開發(fā)了新型可降解鎂合金腹腔鏡手術(shù)止血夾,解決目前該類產(chǎn)品存在的局限性,對(duì)于提高手術(shù)質(zhì)量以及患者術(shù)后身心健康具有重要的現(xiàn)實(shí)意義。本文采用自行研發(fā)的Mg-3Zn-0.2Ca合金,設(shè)計(jì)了可降解鎂合金止血夾的加工工藝流程,制備了可降解Mg-3Zn-0.2Ca合金止血夾,并對(duì)制備過(guò)程中止血夾的顯微組織演變、力學(xué)性能、體外降解行為、細(xì)胞毒性、動(dòng)物體內(nèi)組織相容性以及實(shí)際止血效果等方面進(jìn)行了研究,為進(jìn)一步優(yōu)化鎂合金止血夾的制備工藝以及實(shí)際應(yīng)用效果打下了實(shí)驗(yàn)基礎(chǔ),本文研究工作的主要結(jié)論如下:1.鑄態(tài)Mg-3Zn-0.2Ca合金熱擠壓后,晶粒顯著細(xì)化,并形成了平行于擠壓方向的形變織構(gòu)。沖裁成型后,止血夾邊緣部分晶粒細(xì)化;織構(gòu)特征為(0001)基面平行于擠壓法向平面。退火后,止血夾顯微組織變得均勻,晶粒尺寸隨退火溫度的升高、保溫時(shí)間的延長(zhǎng)而增大;經(jīng)300℃,120min退火后止血夾織構(gòu)類型以(0001)基面織構(gòu)為主,織構(gòu)密度減弱、強(qiáng)度降低。2.ANSYS14.0有限元模擬結(jié)果表明,可降解Mg-3Zn-0.2Ca合金止血夾發(fā)生大塑性變形直至閉合,最大應(yīng)變?yōu)?.247,分布于中間頂端,與實(shí)際情況相符。退火使鎂合金擠壓態(tài)板材強(qiáng)度降低,延伸率增加,止血夾閉合斷裂傾向減小。退火工藝的優(yōu)化結(jié)果為:退火溫度300℃,保溫時(shí)間120min。此工藝處理后,鎂合金止血夾夾閉斷裂現(xiàn)象基本消除,可使乳膠管完全閉合,能抵制乳膠內(nèi)壓力,且一周內(nèi)夾持力無(wú)明顯降低,具有良好的力學(xué)性能。3.可降解Mg-3Zn-0.2Ca合金止血夾體外浸泡48h內(nèi),pH值、失重均隨浸泡時(shí)間的延長(zhǎng)而升高,降解程度加重,腐蝕產(chǎn)物在表面大量堆積。止血夾對(duì)乳膠管的夾持力隨降解反應(yīng)的發(fā)生而下降,浸泡初期降解程度較小,夾持力降低速率較緩慢;浸泡前48小時(shí)止血夾未發(fā)生斷裂,浸泡四天內(nèi)近20%止血夾斷裂,浸泡一周內(nèi)止血夾全部斷裂。4.Mg-3Zn-0.2Ca合金對(duì)小鼠成纖維細(xì)胞無(wú)毒性。鎂合金止血夾大鼠體內(nèi)生物相容性良好:肌肉間植入止血夾1~4周內(nèi),大鼠生命活動(dòng)正常;血生化指標(biāo)正常;組織反應(yīng)合格。鎂合金止血夾能完全夾閉大鼠左腎門血管,血管殘端無(wú)出血,術(shù)后兩周大鼠未發(fā)生滲血,止血夾結(jié)構(gòu)完整,表面發(fā)生降解。
[Abstract]:Titanium alloy hemostatic clamp is a commonly used hemostatic clamp in laparoscopic surgery. Although it is less toxic to human body, its permanent retention in the body will bring about problems such as ionic dissolution inflammation, interference with imaging diagnosis and psychological burden of patients. The absorbable polymer hemostatic clamp can be degraded in vivo, but the structure is more complex, the technical requirements for operators are high, and the cost is high. In order to solve the above problems, a new biodegradable magnesium alloy laparoscopic hemostatic clamp was developed in this paper, which has good biological safety, mechanical properties, especially biodegradable properties in vivo. It is of great practical significance to improve the quality of operation and the patients' physical and mental health to solve the limitations of this kind of products. In this paper, a self-developed Mg-3Zn-0.2Ca alloy was used to design the processing process of the degradable magnesium alloy hemostatic clamp, and the biodegradable Mg-3Zn-0.2Ca alloy hemostatic clamp was prepared, and the microstructure evolution of the hemostat was stopped during the preparation process. The mechanical properties, in vitro degradation behavior, cytotoxicity, animal in vivo histocompatibility and actual hemostatic effect were studied, which laid an experimental foundation for further optimizing the preparation technology and practical application of magnesium alloy hemostatic clamp. The main conclusions of this study are as follows: 1. After hot extrusion, the grain of as-cast Mg-3Zn-0.2Ca alloy is refined remarkably, and the deformation texture parallel to the extrusion direction is formed. After blanking, the grain on the edge of hemostasis clamp is refined, and the texture characteristic is (0001) base plane parallel to the normal plane of extrusion. After annealing, the microstructure of the haemostatic clamp becomes uniform, and the grain size increases with the increase of annealing temperature and the prolongation of holding time. After annealing at 300 鈩，

本文編號(hào)：2450359