高原高寒战时环境猪肢体枪弹伤后全身炎症反应的特点

目的 目的探讨高原高寒环境下平战时猪枪弹伤后血浆中肿瘤坏死因子α(TNFα)、白介素-1b(IL-1b)、白介素-4(IL-4)、白介素-10(IL-10)、一氧化氮(NO)等炎症介质和内毒素含量变化的规律.方法 将实验小型猪24头随机分为高原战时致伤组(GZ)、高原平时致伤组(GP)和平原平时致伤组(PP).每组8头...     

速眠新Ⅱ复合戊巴比妥麻醉在猪高速投射物致伤模型制备中的应用

目的:探讨速眠新Ⅱ复合戊巴比妥对实验小型家猪在高速投射物致伤模型制备中的麻醉效果.方法:小型家猪以速眠新Ⅱ0.1 ml·kg-1肌注基础麻醉后,静脉复合0.3%戊巴比妥溶液0.5 ml·kg-1诱导维持麻醉,观察麻醉后高速投射物致伤过程中猪的基本生命体征,判断麻醉效果.结果:动物麻醉平稳,致伤前后动物心率和呼吸等生命体征稳定;其中1例出现麻醉副作用.体温随着麻醉持续时间延长呈下降趋势,但不显著.结论:速眠新Ⅱ基础麻醉,静脉复合戊巴比妥诱导维持,此方法用于猪高速投射物致伤模型制备麻醉效果稳定延长,操作简便.     

猪后肢枪弹伤前后肺血管容积CT与血生化指标变化趋势研究

目的 采用容积CT(VCT)评价猪后肢枪弹软组织贯通伤前后肺动脉血管容积与血浆生化指标变化特点.方法 12只普通家猪,雌性,4~5个月,35~40 kg.采用81-1自动步枪,子弹7.62 mm,致伤能量508.48～520.37 J,枪击猪后肢,制成下肢软组织贯通伤-肺损伤动物模型.分别于致伤前和致伤后3 min、10 min、25 min、40 min时间点,采用VCT行胸部常规及增强扫描,利用VCT AW4.2工作站自带软件进行后处理,测量各时间点两下肺外侧基底段动脉分支容积;同时在各时间点经耳缘静脉采血,检测血浆中内皮素(ET)、皮质醇(COR)、丙二醛(MDA)、超氧化物歧化酶(SOD)、总抗氧化能力(T-AOC)的浓度变化.对照分析各时间点肺动脉血管容积与血浆生化指标的变化特点与趋势.结果 (1)致伤后3 min两肺下叶外基底段动脉容积较致伤前增加(tR=-9.98,PR＜0.05;tL=-14,PL＜0.05);致伤后10 min较致伤前减少(tR=9.125、PR＝0.018;tL=11,PL＜0.05);致伤后25 min、40 min两肺下叶外基底段动脉容积恢复至致伤前水平.(2)血浆ET浓度致伤后10 min升至最高点与致伤前比 较(t=9.21,P＜0.05),血浆COR浓度致伤后10 min、25 min、40 min与致伤前比较均有统计学差异(t10 min=21,P＜0.05; t25 min=17,P＜0.05; t40 min=13,P＜0.05),在致伤后10 min达到最高峰.(3)致伤前后血浆SOD、MDA 、T-AOC浓度在各时间点变化无统计学差异.结论致伤能量为508.48～520.37 J的国产自动步枪所致的猪后肢软组织贯通伤可导致远隔肺损伤;损伤早期两肺下叶外基底段动脉容积增加,伤后10 min血浆ET、COR达到峰值,此时肺小动脉容积明显减小;血浆MDA、SOD、T-AOC浓度无特异性变化.     

BioLiver-Ⅰ型生物人工肝支持系统治疗两种急性肝衰竭犬的实验研究

目的评价BioLiver-Ⅰ型生物人工肝支持系统(BALSS)治疗两种急性肝衰竭(ALF)犬的效应.方法采用多次皮下注射醋氨酚的方法建立急性药物中毒ALF模型犬;应用手术切除80%的肝脏建立少肝ALF犬模型.分离中国实验用小型猪肝细胞并培养于BALSS中,对两种ALF犬进行6h的交叉灌流,观察治疗前后犬生理、生化和组织学的变化.结果注射醋氨酚48h后可建立ALF犬模型,模型成功率为63.3%;肝大部分切除手术后24h可建立ALF模型,模型成功率为84.2%.应用作者改进的酶消化法,从每只小型猪的肝脏平均可获得(1.0～3.0)×1010个肝细胞且存活率较高.应用BioLiver-Ⅰ型BALSS对两种ALF犬进行治疗后,相关的血液生化指标明显改善,肝脏的病理损伤得以修复.药物诱发的ALF犬长期存活率高于手术组.BALSS治疗对其他脏器无明显损伤.结论 BioLiver-Ⅰ型BALSS能够安全有效地为两种ALF犬提供肝功能支持,可望成为救治ALF的重要方法.     

新型心肌显像剂[99Tcm(N)(PNP5)(DBODC)]+猪心肌显像研究

目的 评价新型心肌显像剂[99Tcm(N)(PNP=5)(DBODC)]+在猪体内的药代动力学特征及生物分布特性.方法 利用药盒法制备[99Tcm(N)(PNP5)(DBODC)]+注射液.实验动物选7头实验用成年健康中华小型猪,由耳静脉注入[99Tcm(N)(PNP5)(DBODC)]+,分别于注射后2,5,10,15,30,45,60,75,90,120,150和180 min从猪后肢静脉进行血样采集以获得药代动力学参数,同时进行胸腹部平面系列显像,以观察该药物在猪体内的生物分布和靶/非靶比值,并与99Tcm-甲氧基异丁基异腈(MIBI)显像比较(采用配对t检验).结果 [99Tcm(N)(PNP5)(DBODC)]+标记率为(95.54±0.85)%,其符合一次静脉给药的药代动力学二室模型,分布半衰期T1/2á=(2.97±0.48)min,消除半衰期T1/2a=(52.49±19.49)min,血液总清除速率(CL)=(14 314.29.±8445.79)ml/h.心、肝、肺时间-放射性曲线显示[99Tcm(N)(PNP5)(DBODC)]+肝摄取在初始时明显高于心肌,但肝内放射性清除迅速,在注射30 min后,肝内放射性已低于心肌放射性,而99Tcm-MIBI肝摄取在180 min内均高于心肌.[99Tcm(N)(PNT5)(DBODC)]+的心/肝比值在注射后30～180 min均高于99Tcm-MIBI(t值为10.395～54.482,P均＜0.05).显像示在注射[99Tcm(N)(PNP5)(DBODC)]+后5～180 min均可获得清晰的心肌图像,肝内示踪剂迅速排入胆、肠系统,致使肝内放射性迅速减低,有利于减少对左室下壁的干扰.结论 [99Tcm(N)(PNP5)(DBODC)]+有望成为一种新的心肌灌注显像剂.     

腹部多发脏器伤模型的建立及评价

5.2±0.1cm2,毁损最长径为5.6±0.2cm;胰腺毁损长度6.3±0.2cm.MAP下降一半的时间为8.8±0.5min,MAP下降一半时出血量为704.7±14.6ml,致伤后死亡时间(前5只)为25.4±1.8min,ISS为28.0±0.8.成功建立小型猪腹部多发脏器伤模型.结论 利用自制的致伤引爆装置及电子鞭炮制备腹部多发脏器伤模型具有可重复性、可控性及稳定性良好等特点,可用于交通伤和野战外伤等救治的实验研究.     

医用多糖止血愈合海绵对小型猪股动脉出血模型的止血作用研究

目的 研究医用多糖止血愈合海绵(MP)在小型猪股动脉出血模型中的止血作用.方法 采用小型猪32只制作股动脉出血模型后随机分为4组(n=8),分别采用MP、羧甲基纤维素(CMC)、明胶海绵(GS)和医用纱布(MG)进行创面外敷止血,观察各组的止血时间、失血量及小型猪生命体征.结果 建立小型猪股动脉出血模型后,各组动物平均动脉压无明显差异.MP组、CMC组、GS组的止血时间及失血量均明显低于MG组(P＜0.01),且CMC组的止血效果优于MP组和GS组,而MP组和GS组的止血效果相似.结论 MP、CMC敷料对小型猪股动脉止血效果确切,与GS相似或略优于GS.     

声学密度技术评价肢体枪弹伤心脏远达效应的实验研究

火器伤所致远达效应发生率高 ,伤情隐蔽 ,容易误诊误治[1] 。笔者试图探讨应用声学密度技术诊断肢体枪弹伤心脏远达效应的价值。一、材料与方法1.动物分组及致伤 :成都地区猪 2 3只 ,体重 (2 5 .6± 2 .2 )ｋｇ ,雌雄不限。随机分为致伤组 18只 ,对照组 5只。致伤组以氯胺酮麻醉后 ,以国产 5 6式冲锋枪、7.6 2ｍｍ弹 (710ｍ/ｓ、射距 5ｍ)射击致伤左后肢中段肌肉丰满处 ,伤口包扎止血 ,改用 30ｇ/Ｌ的戊巴比妥钠维持麻醉。以致伤后心脏出现组织学改变为心脏远达效应发生标准 ,再将致伤组分为远达效应损伤组 (效应组 )和无远达效应损伤组 (非…     

猪后肢枪弹伤前后肺循环VCT形态学变化的多点动态测量分析

目的 分析猪后肢枪弹贯通伤对肺灌注的影响.方法 普通家猪,雌性,4～5月,35～40 kg,12只,由第四军医大学实验动物中心提供.采用81-1自动步枪,子弹7.62 mm,枪击猪后肢制成下肢软组织贯通伤-肺损伤的动物模型,分别于致伤前和致伤后3 min、10 min、25 min、40 min时间点,采用64排CT进行胸部常规及增强扫描,利用VCT AW4.2工作站自带软件进行后处理,测量各时间点1～5级肺血管管径和容积变化.结果 经t检验,①致伤前及致伤后3 min、10 min、25 min、40 min各时间点双肺1～5级动静脉管径的变化两两比较,无统计学意义(P＞0.05).②致伤后3 min两肺下叶外基底段动脉的血管容积较致伤前增加(P＜0.05);致伤后10 min较致伤前减少(P＜0.05);致伤后10 min较致伤后3 min两肺下叶外基底段动脉的血管容积减少(P＜0.05); 致伤后25 min较致伤后10 min两肺下叶外基底段动脉的血管容积增加 (P＜0.05);致伤后40 min与25 min两肺下叶外基底段动脉的血管容积无明显变化(P＞0.05).致伤后25 min、40 min两肺下叶外基底段动脉的血管容积恢复至致伤前水平(P＞0.05).结论 肺循环1～5级肺动静脉血管的管径在猪后肢致伤前和致伤后3 min、10 min、25 min及40 min各时间点改变不明显;而在致伤后3 min肺血管容积增加最明显,其后缓慢下降,25 min恢复至致伤前水平.     

生物可降解腔静脉滤器的制备及其性能研究

目的 对采用左旋聚乳酸(PLLA)制备生物可降解腔静脉滤器(BVCF)进行研究,并评估其机械力学性能、可输送性能、捕获血栓性能及其生物相容性.方法 利用三维设计软件设计BVCF外形,采用分子量为100 000 U的PLLA制作BVCF,通过体外实验,对其主要性能进行测试.采用中华小型猪12只,随机分为4组(每组3只),第1～3组为实验组,第4组为对照组.将9枚BVCF置入第1～3组实验小型猪下腔静脉内,1周后对所有小型猪行血栓注入实验.每组的3只小型猪下腔静脉分别注入2、5和8条血栓.注入血栓后l、6、12周行影像检查,观察滤器情况及小型猪肺动脉栓塞情况.每次影像检查后,牺牲1组实验组动物行病理检查.结果 制备出一种带中心线型的可降解滤器,通过体外实验测试滤器径向支撑力1.6N,能够捕获直径＞5 mm的栓子,易于释放.通过动物实验证实该滤器能够捕获注入的致命性栓子,9只实验组小型猪均存活,其中2只栓子注入过程中出现轻度呼吸、心率加快；对照组小型猪注入血栓后不同程度地出现呼吸频率加快、气促等症状,注入8条血栓的小型猪,在血栓注入后当天死亡.术后影像及病理检查显示,实验组出现症状的小型猪发生周围性肺动脉栓塞,对照组死亡小型猪发生中央性肺动脉栓塞.显微镜下显示滤器置入术后1周,BVCF侧支部分被内膜覆盖；6周后完全被内膜覆盖,血管壁结构正常,未见明显炎性细胞浸润；术后12周BVCF侧支内膜情况无明显变化,滤器侧支部分降解.结论 BVCF具有良好的机械强度和可输送性能,对致命性大栓子有较高的捕获率,并具有良好的生物相容性,但其降解性能尚需进一步研究.     

Heart pathology associated with exposure to high sustained +Gz.

The pathology of +Gz acceleration was examined using unanesthetized adult miniature and immature "farm-type" swine, with and without anti-G suit inflation. Following single exposures of +8 or 9 Gz for 45 to 90 s--acceleration exposures that have been shown "tolerable" to man--swine were sacrificed and a detailed necropsy performed. Considering only the adult miniature swine, the endocardial area of the left ventricles showed evidence grossly of recent hemorrhage of varying severity involving both the wall and papillary muscles. The degree and location of the subendocardial hemorrhage were quantitated by grading the area of ventricle involved--1 (slight) to 4 (extensive). Of the 23 adult miniature pigs autopsied, the scores for papillary muscle hemorrhage, after one exposure to +9 Gz (45 to 90 s) ranged from a mean of 2.3 to 3.3 and the extent of ventricular wall involvement was 2.5 to 3.3. Histologically, heart hemorrhage was limited to the subendocardial area, primarily involving the space between heart muscle and the endocardium and was particularly evident surrounding Pukinje's fibers. Similar studies using immature farm-type swine (not miniature pigs) found these younger swine (4 to 5 months of age) to be less susceptible to such endocardial hemorrhage. Heart tissue recovery in these pigs following one exposure to +9 Gz for 45 s, required approximately 14 d. It appears that this lesion is similar, although less severe, than heart muscle lesions associated with loss blood volume (hemorrhagic shock) studies and may have similar physiologic bases. It was concluded that particular attention should be made of the endocardium of victims of high-performance aircraft accidents.     

Use of vectorcardiography for the detection of +Gz-related cardiac pathology in miniature swine

Vectorcardiograms were recorded from anesthetized, adult miniature swine 1-2 weeks before high sustained +Gz exposure and 2-6 h after exposure. Each +Gz run consisted of one 60-s exposure, respectively, to 3, 5, 7, and 9 +Gz, with 3 min rest between each +Gz plateau. The full range, from severe to minor, of +Gz-induced cardiac pathology was observed in this group of miniature swine. In spite of the large variation in the amount and degree of cardiac pathology, there were no post-exposure vectorcardiographic changes which might be diagnostic of +Gz-induced cardiac pathology. The results of this study indicate that vectorcardiography, performed after +Gz exposure, is not a reliable technique for detecting the presence of +Gz-induced cardiac pathology in miniature swine.     

1999 Gary J. Becker Young Investigator Award. MR-guided transjugular portosystemic shunt placement in a swine model.

PURPOSE: To evaluate the performance of portal venous puncture with use of magnetic resonance (MR) guidance, and to place a transjugular intrahepatic portosystemic shunt (TIPS) in a swine model. MATERIALS AND METHODS: A study of 12 swine was performed to evaluate the ability of interventional MR imaging to guide portal vein puncture and TIPS placement. Six swine had catheters placed in the right hepatic vein under C-arm fluoroscopy. A nitinol guide wire was left in the vein and the animals were then moved into an open configuration MR imaging unit. A TIPS needle set was used to puncture the portal vein using MR fluoroscopy. The animals were transferred to the C-arm, and venography confirmed portal vein puncture. A follow-up study was performed in six additional swine to place a TIPS using only MR imaging guidance. MR tracking was used to advance a catheter from the right atrium into the inferior vena cava. Puncture of the portal vein was performed and a nitinol stent was placed, bridging the hepatic parenchyma. MR venogram confirmed placement. RESULTS: Successful portal vein puncture was achieved in all animals. The number of punctures required decreased from 12 in the first animal to a single puncture in the last eight swine. A stent was successfully placed across the hepatic tract in all six swine. CONCLUSIONS: Real-time MR imaging proved to be a feasible method to guide portal vein puncture and TIPS placement in pigs.     

经颈静脉肝内门体静脉内支架分流术术式改良的实验研究

目的：探讨建立改良式猪经颈静脉肝内门体静脉内支架分流术（TIPSS）模型的可行性及其意义。方法：11只家猪分成2组，7只采用改良术式（经肝段下腔静脉穿刺门脉）建立TIPSS模型，另4只行常规TIPSS作对照。共置入4枚进口覆膜镍钛合金支架，8枚国产覆聚氨酯膜支架。其中，改良组7只猪置入7枚支架（4枚进口支架，3枚国产支架）；对照组4只猪置入5枚国产覆膜支架（1只猪置入时支架发生移位，故加用1枚支架）。术后4周（5只），8周（2只）和12周（4只）进行门脉造影观察分流道通畅情况。动物处死后，行分流道大体和组织病理学检查。结果：术后4周，改良组2只分流道通畅（进口支架、国产支架各1枚），分流道表面均形成完整的假性内膜组织；另5只分流道在4至12周均闭塞，分流道内形成血栓，其中2只内支架伸入下腔静脉内不全，陷入肝实质内。常规组4只分流道在4、8和12周观察期内均闭塞。两组间分流道肝（下腔）静脉端，肝实质段和门静脉端各段的增生组织厚度对比差异均无显著性意义（t值分别为0．14、0．16和0．20，P值均＞0．05）。结论：改良式猪TIPSS模型的建立是安全和可行的。改良式TIPSS中应采用覆膜支架，并应有足够长度伸入至两端静脉内，有助于防止增生组织向分流道内长入。     

Visualization of vascular guidewires using MR tracking

MR tracking of a vascular guidewire sized for a .035-inch (.89-mm) catheter lumen was performed. The guidewire was actively tracked by incorporation of a miniature radiofrequency (RF) receive coil built into its tip. After in vitro validation, simultaneous tracking of the guidewire and a catheter was performed in the aortic and abdominal vessels of a swine at 1.5 T. The ability to track such a small device and the ability to simultaneously track multiple devices are significant steps towards vascular interventions under MR guidance.     

Inhibition of pseudointimal hyperplasia in swine TIPS models: the efficacy of local delivery of paclitaxel using a perforated balloon catheter

The aim of this study was to investigate the efficacy and feasibility of local delivery of paclitaxel to inhibit pseudointimal hyperplasia/intimal hyperplasia in swine transjugular intrahepatic portosystemic shunt (TIPS) models TIPS were created in seven healthy domestic swine (15-20 kg). Before TIPS stent insertion, we performed a short-term infusion of paclitaxel (treatment group: n = 4) and saline (control group: n = 3) into the TIPS tract using a balloon catheter in which two 0.010 inch holes were created on opposite sides of the balloon. Paclitaxel or saline was given to all animals via the hepatic parenchymal and venous outflow tract. The animals were followed for up to two weeks and then killed. Gross and histological evaluations of the shunts were performed, and the maximum pseudointimal/intimal hyperplasia thicknesses were calculated for each animal The average infusion time of paclitaxel or saline was 7.6 min (6-9 min). At gross and histological evaluation, considerable pseudointimal hyperplasia had formed in the control group and statistically significant differences were found upon microscopic evaluation in the maximum pseudointimal hyperplasia thickness between the control (2.41 mm, range 1.7-3.16 mm) and animals receiving paclitaxel (0.63 mm, range 0.42-0.98 mm, p<0.05) Local delivery of paclitaxel at the time of TIPS creation may have been effective in reducing pseudointimal/intimal hyperplasia in swine TIPS models.     

Improved Patency of Transjugular Intrahepatic Portosystemic Shunt: The Efficacy of Cilostazol for the Prevention of Pseudointimal Hyperplasia in Swine TIPS Models

Purpose To investigate the efficacy of oral administration of cilostazol to inhibit pseudointimal/intimal hyperplasia in swine TIPS models. Methods Successful TIPS creation was carried out in 11 of 12 healthy young pigs (20–25 kg). In the treatment group (n = 6), both cilostazol and aspirin were administered daily, from the first day of TIPS creation. The control group (n = 5) was administered only aspirin. The animals were followed-up for 2 weeks and then killed. The specimen (including portal vein, hepatic parenchymal tract, hepatic vein, and inferior vena cava) and stents were carefully bisected in a longitudinal fashion. The control group was compared with the treatment group by means of a gross and histologic evaluation of the degree of pseudointimal/intimal hyperplasia in the shunt. Results At the gross evaluation, the control group showed considerably more pseudointimal/intimal hyperplasia than the treatment group. Using microscopic evaluation, there was a statistically significant difference (p < 0.05) in the mean maximum pseudointimal/intimal hyperplasia thickness between the control group (2.97 ± 0.33 mm) and treatment group (0.73 ± 0.27 mm). Conclusion Oral administration of cilostazol may have been effective in reducing pseudointimal/intimal hyperplasia in swine TIPS models.     

Intravascular Ultrasound Guidance for Transjugular Intrahepatic Portosystemic Shunt Procedure in a Swine Model

A new method is described for guiding hepato-portal venous puncture using a longitudinal side-view intravascular ultrasound (L-IVUS) transducer to assist in the performance of transjugular intrahepatic portosystemic shunt (TIPS) in three Australian swine. Simultaneous L-IVUS with an AcuNav® 5–10 MHz 10 Fr transducer (Acuson Corporation, Mountain View, CA, USA) and fluoroscopy guidance was used to image and monitor the hepatic to portal venous puncture, dilatation of the tract, and deployment of the TIPS stent. Flow through the shunt could be demonstrated with both L-IVUS and angiography. TIPS was successful in all swine. The time for portal vein puncture once the target portal vein was identified was reduced at each attempt. The number of portal vein puncture attempts was 2, 1, and 1. No post-procedural complication was evident. L-IVUS-guided TIPS is practical and has the potential to improve safety by permitting simultaneous ultrasound and fluoroscopic imaging of the needle and target vascular structures. This technique allows for a more streamlined approach to TIPS, decreasing the fluoroscopic time (hence, decreasing the radiation exposure to the staff and patient) and anesthetic time. In addition, there are improved safety benefits obviating the need for wedged portography, facilitating avoidance of bile duct and hepatic arterial puncture, and minimizing hepatic injury by decreasing liver capsular puncture and the attendant risks.     

"Atraumatic" transjugular needle for portal vein puncture in swine

A new coaxial needle-catheter system was designed for transjugular portal vein puncture in young domestic swine. It was tested in 32 animals and successfully entered the portal circulation via a hepatic vein or intrahepatic portion of the inferior vena cava. No complications were encountered.     

Forcible Intraarterial Injection of a Nonadhesive Liquid Embolic Agent under Microballoon Occlusion: Experimental Study in Swine Liver

PurposeTo evaluate the feasibility and effectiveness of transcatheter embolization by forcible intraarterial injection of a mixture of ethylene vinyl alcohol copolymer (EVAL) and ethanol under microballoon occlusion compared with conventional transcatheter arterial embolization methods in nontumoral swine liver.Materials and MethodsNine swine were divided into three groups: embolization with EVAL/ethanol mixture (EVAL group, n = 5), with ethiodized oil (ethiodized oil group, n = 2), and with microspheres (microspheres group, n = 2). Embolization was performed at the subsegmental hepatic artery. The EVAL/ethanol mixture was injected forcibly through a microcatheter with a balloon, which was inflated to prevent backflow of the mixture during the injection. Ethiodized oil or microspheres were injected into the artery using a microcatheter without balloon occlusion. Two animals of the EVAL group were euthanized immediately after embolization, and the distribution of EVAL was assessed microscopically. The remaining seven animals were euthanized 4 weeks after embolization, and the histopathologic changes were assessed.ResultsAll procedures were technically successful. EVAL occupied > 80% of the hepatic arterial, portal venous, and sinusoidal lumens after embolization. Ischemic coagulation necrosis was observed 4 weeks after embolization in the EVAL group. Parenchymal necrosis was not observed in the ethiodized oil and microspheres groups.ConclusionsTranscatheter embolization by forcible intraarterial injection of an EVAL/ethanol mixture under microballoon occlusion was feasible and achieved the simultaneous embolization of hepatic artery, portal vein, and sinusoids in swine liver, resulting in complete necrosis of the segment that received embolization.