【作者】 张鸿毅；

【导师】 保庭毅；

【作者基本信息】 第四军医大学 ， 外科学， 2008， 硕士

【摘要】 研究背景与目的:环境内分泌干扰物是指一些可能影响负责机体自稳、生殖和/或行为的天然激素的合成、分泌、转运、结合、作用或消除的外源性物质,具有亲脂性、不易降解、残留期长等特点,其对人类生殖健康的危害是当前人们关注的一个焦点。其中邻苯二甲酸二异辛酯,又名邻苯二甲酸二(2-乙基)己酯[Di-(2-ethylhexyl)phthalate(DEHP)],作为一种常用的塑料制品增塑剂,因其具有内分泌活性,已造成了全球性的严重污染,尤其对于男性生殖系统的影响最为显著,其对前列腺的生长、发育、分化及成年后前列腺疾病的发生有重大影响。本实验就DEHP对大鼠前列腺的影响进行初步探讨。研究方法:将SD大鼠随机分为4组,每组8只,(1个空白对照组和3个DEHP染毒组)。染毒组分别用DEHP浓度为50mg/(kg.d)、200mg/(kg.d)、500mg/(kg.d)。从5周龄开始,每天定时腹腔注射染毒8周。空白组、染毒组都自由进食、进水。于14周龄时处死大鼠,剖腹仔细分离后摘除前列腺,将剥离干净的前列腺置容积测量仪中,测量其体积(cm3);取出前列腺置滤纸上,吸干水后用电子天平称其湿质量(mg),并计算前列腺指数。前列腺指数=[前列腺湿质量(g)/大鼠体质量(g)]×100%。取相同部位前列腺组织,4%多聚甲醛溶液固定48h,逐级乙醇脱水、浸蜡,石蜡包埋,切片,片厚4μm,常规苏木精-伊红染色,在光学显微镜下观察前列腺组织结构的变化。采用SPSS12.0医学统计软件进行数据分析,各组间多组均数比较采用单因素方差分析,并作样本均数两两比较的q检验。研究结果:前列腺重量、体积及指数的测定染毒组大鼠前列腺重量、体积、前列腺指数均明显高于阴性对照组(P<0.05),并呈现一定的剂量相关性。镜下见正常对照组腺体排列清楚,腺腔无扩张,腺上皮单层柱状,可见少许基底细胞及明显基膜,腺体间可见较明显的间质。模型组腺体排列密集,部分腺腔扩张、变大,可见较多基底细胞,间质增多,尤以平滑肌增多明显,小血管扩张充血。符合前列腺增生的表现。研究结论:尽管前列腺增生发生的机制至今仍不完全清楚,但近年来的研究普遍认为,雌雄激素的比例失调是导致前列腺增生的主要原因之一。前列腺是人体最大的性腺附属器官,它的生长、发育、分化受雌雄激素的调节,在老年男性,随着年龄的增加,睾丸功能减退,体内雄激素水平下降,雌/雄激素比例失调,雌激素水平相对升高,从而导致前列腺增生。DEHP是一种环境内分泌干扰物,许多学者认为其对动物雌激素呈显著干扰效应,能够模拟雌激素的生理功能,与内源性雌激素竞争性结合血浆性激素结合蛋白,使之脱离血浆结合蛋白,引起内源性雌激素生物利用度增高,作用增强,从而干扰内分泌系统,使雌雄激素比例失调。因此我们推测,DEHP的摄入所引起的体内雌雄激素比例失调可能是其诱导前列腺增生的原因,其具体机制仍需进一步探讨。研究背景:战伤、车祸伤、手术或其他原因导致的腹膜后出血是常见的临床急症。因腹膜后间隙巨大且位置较深,可容纳大量的出血,故临床表现错综复杂,容易漏误诊,如诊疗不及时,可引起严重的后果或并发症,甚至死亡。但因腹膜后位置较深,临床症状不典型,一般的查体不易发现,因而易导致误诊及延误病情治疗。目前,对于创伤导致的腹膜后出血临床常用的检查和诊断方法有CT、B超、MRI等。但是,这些仪器均只能采集患者某一时间点的出血情况,诊断出血,而不能对患者的出血情况进行实时监控,对于疾病的转归、发展不能做的连续性监护。而且设备昂贵,不能行床旁检查,对于危重患者及不宜搬动的患者进行检查较困难,且风险较大。因此,临床上迫切需要一种便携、快速、廉价而且可以持续监测患者出血情况的仪器。目前,利用电阻抗成像技术(EIT)来监测出血是近年来才发展起来的一个新的监护手段。EIT的实现基础是生物体内细胞膜具有低的漏电特性的绝缘膜,不同组织、甚至同种组织的不同状态所表现的阻抗值都不同,因此,以生物体内电阻抗分布或变化为成像对象成为可能。EIT是一种非侵入式的医学成像方法。通过对成像目标周围的电极注入交变电流,并同步测量边界电压,来获得目标内部导电参数的分布,利用图像重构算法对相敏解调技术得到的变换阻抗数据进行重构,形成阻抗断层图像。因为同种组织的不同状态其阻抗值也不同,所以,利用EIT设备监测组织阻抗的变化就可以了解组织的生理或病理状态,如心博量、创伤、出血、肿瘤等等。且该设备具有非侵入性,无辐射,造价低廉,适用于对患者进行长期监护,而这些特性恰恰是目前多数临床成像手段难以达到的。研究方法:本研究利用EIT技术,对腹膜后出血变化状况进行仿真研究,通过建立两种不同的模型,即腹膜后注血模型和出血模型,对EIT监测腹膜后损伤的可靠性进行研究,旨在揭示小猪腹膜后出血情况与EIT图像之间的关联,为腹膜后出血诊断新方法的研究及应用于腹膜后出血的临床诊断提供实验基础。①使用B超引导穿刺置管至小猪腹膜后间隙,通过电子输液泵将同种异体抗凝血液按一定速度注入小猪腹膜后,同时使用EIT监测腹膜后注血情况,并行CT及解剖验证,以了解注血量与注血速度与EIT图像的关联;②使用B超引导穿刺小猪肾脏,同时将小猪全身肝素化,使用EIT监测腹膜后出血情况,并行CT及解剖验证,以了解出血量与EIT图像之间的关联。研究结果:1.注血组5头小猪在实验结束时均存活,小猪麻醉平稳,行CT扫描验证。结果发现小猪右侧腹膜后可见注血导管影及腹膜后血肿,位置局限。腹腔内脏器结构完整,未见腹腔内出血或积液。解剖发现5头小猪后腹膜均完整,未损伤,腹腔内未见血液。右侧腹膜后可见一处巨大血肿。打开后腹膜可见注血导管位于肾脏与腰大肌之间,肾脏、腰大肌与腹膜后大血管未见损伤。2.注血组实验开始时,EIT系统图像灰度均匀,随着小猪腹膜后注血量的增加,EIT图像的灰度都有明显的变化,图像上可见逐渐阻抗减小的区域,且与注血部位吻合。在每次更换注射器之间5-10分钟采集的图像稳定。3.出血组5头小猪在经肾脏穿刺后3小时均存活,实验后行CT及解剖发现5头小猪后腹膜均完整,未损伤,腹腔内未见血液。右侧腹膜后均有大量积血,积血量分别在100ml～180ml之间,出血率达100%。经统计计算,用此模型建造的出血量均数的95%可信区间为135.59ml±11.69ml。检查腹腔其他脏器及大血管,均未见损伤。实验结果表明,该小猪腹膜后出血模型的建立是成功的。4.出血组实验开始时,EIT系统图像灰度均匀,随着小猪监护时间的延长,EIT图像随着时间的变化EIT图像上可见逐渐阻抗减小的区域,图像灰度值不断变小,且与通过CT及解剖证实的右侧腹膜后出血部位吻合。结论:1.腹膜后注血模型穿刺位置一致,模型与真实的腹膜后出血类似;因采取定时、定量注血,可得到精确的图像变化与注血量的关系;模型穿刺位点恒定,注血速度、注血量可以量化控制,故实验的控制性和重复性较好;腹膜后出血模型具有穿刺位点恒定,定位精确,造成的肾脏出血可靠,与真实的腹膜后出血类似,实验的控制性和重复性好等优势。实验设备简单,可靠性高。实验结果表明,用这两种方法建立的动物模型是成功的,可满足无创性腹腔出血诊断方法研究的需要。2.电阻抗成像系统能够准确地反映出腹膜后阻抗变化的情况,并能测出阻抗变化区域,系统成像清楚,出血与未出血图像比较反差大,图像对比度明显,并随出血量的增多图像灰度反差增大。且该设备简单,可靠性高,具有非侵入性,无辐射,造价低廉的特点,适用于进行长期监护。更多还原

【Abstract】 The Endocrine disrupting chemicals (EDCs)are exogenous material which candisturb hormone synthesis, secretion, transport and effect. They are lipophilicify andhard to degradation. It can damage human’s reproduction. The Di-(2-ethylhexyl)phthalate (DEHP)is a kind of plasticizer that has hormone activity has made severepollution all over the world. DEHP can disturb male’s reproductive ability specificallyand it can influence prostate grown, development, differentiation and cause prostatediseases. So we designed this experiment to research the relationship between DEHPand prostate.Thirty-three SD rats were divided into four groups randomly : normal controlgroup , low dose DEHP group [50 mg/(kg·d)] , middle dose DEHP group[(200mg/(kg·d)], and high dose DEHP group [500 mg/(kg·d)]. Different dosages of DEHPwere administered to SD rats with injection of abdominal cavity from the fifth weeksafter birth to thirteen weeks . After the rats were killed , the prostate was dissected andweighted , the prostate volume was measured and the prostate index was calculated.Prostatic tissues were stained by hemoloxylin, eosin and immunohistochemistry, thenmorphological changes of prostate tissues were observed by light microscope. In comparison with normal group , prostatic volumes and weight as well as theprostate index were significantly increased ( P < 0. 05) with glands expanded andinterstitial tissues increased, and the degree of prostatic hyperplasia show a positivecorrelation with the dose of DEHP. Exposure to DEHP on male rat during the period ofadolescent age may induce prostate hyperplasia which manifests enlargement ofglandular lumen accompanied by hyperplasia of interstitial tissues.The prostate is biggest sex gland organ and it is controlled by sex hormone. TheDEHP is a kind of EDCs, so it disturb the normal sex hormone’s function. So we thinkthe DEHP can lead prostate hyperplasia, but the mechanisms we need to investigatefurther. Retroperitoneal bleeding is very common in clinic. Because of the space ofretroperitoneal is very huge and deep, it can contain many blood, so clinicalmanifestation is very complicated. It can induce very severe consequences andcomplications, even death. But the diagnostic methods of retroperitoneal bleedinginclude CT, ultrasound, MRI etc. But all of those methods can’t monitor the patients’real time bleeding, they can’t be used at bedside. It’s very high risks for the patients whocan’t move. So we need a equipment that can continue monitoring the bleeding. Now,the electrical impendence tomography (EIT) is a new tool to monitor bleeding.The EIT base on the cellular membrane is a kind of insulation membrane that havevery low electrical leakage character. Different tissues, even different condition of sametissues have different electrical impedances. So we can use this character to make thetomography to monitor the bleeding. This equipment is non-invasive, it can monitor theelectrical impedances of tissues that we can know the physiological functions andpathological conditions of tissues. This equipment is suitable, no radiation, non-invasiveand can get the bleeding message real time, all of those characters are very difficult for most medical equipments.We use the EIT technology to monitor retroperitoneal bleeding and we use twodifferent models, the retroperitoneal inject blood model and retroperitoneal bleedingmodel. We want to reveal the relationship between retroperitoneal bleeding and EIT, andwe hope to find a new method to diagnose retroperitoneal bleeding. The first model, weinsert a vessel into retroperitoneal and inject blood to simulate retroperitoneal bleedingand use EIT monitoring the pigs. When we finish monitoring, all pigs are inspected byCT and anatomy. The second model, pigs retroperitoneal bleeding model is establishedby the puncturatio of kidney from outside with fine needles guided by ultrasound, andpigs are heparinized at same time. All those pigs are inspected by CT and anatomy too.The 5 pigs of retroperitoneal inject blood model are all survival when the monitor isover. All pigs’anesthesia are steady. The CT tomography reveal that the rightretroperitoneal of pigs have the vessel and hematoma, and the hematoma is localized.The organs in abdominal cavity are integrity and no blood or fluid in there. The anatomyresults find all pigs’post peritonaeum is integrity, no blood in abdominal cavity, and onehuge hematoma is in retroperitoneal cavity. The vessel between the kidney and greaterpsoas muscle, the kidney, greater psoas muscle and great vessels are not injured. Thegray scale of EIT images are uniformity before we inject blood and the gray scale of EITimages change enormously when the more and more blood are injected intoretroperitoneal cavity. We can see the area that the electrical impendence decreasegradually, and the images are steady when we change the injector.The 5 pigs of retroperitoneal bleeding model are all survival when the kidney hasbeen punctured three hours. The CT and anatomy all find that every pigs’postperitonaeum is integrity, no blood in abdominal cavity, and the volume of hematoma inretroperitoneal cavity is from 100ml~180ml, bleeding rate is 100%. All the other organs and vessels are not injured. When EIT start monitoring, the gray scale of EIT images areuniformity and decrease enormously when the monitoring time prolong. The area isconsistent with the CT and anatomy.The retroperitoneal inject blood models have same site to puncture, and the modelsparallel the real retroperitoneal bleeding. We inject blood with determinate time andspeed, so we can get precise relationships between images and blood volume. We cancontrol the speed, blood volume, so we can repeat the experiment easily. Theretroperitoneal bleeding models cause kidney bleeding is very similar real retroperitonealbleeding. The EIT equipment is simple, suitable and reliable. The consequences of twomodels reveal the models are successful, they can fit the need to study the retroperitonealbleeding.The EIT can monitor the retroperitoneal bleeding sensitively and can monitor thebleeding area, the images are clear and easy to read. The contrast increases when theblood volume increase or bleeding time prolong. Because of its simple, reliable, noninvasiveand no radiation, the EIT refer to long time monitoring at bedside.更多还原