吻合血管同种异体骨移植术后微嵌合现象的研究

目的 研究吻合血管同种异体骨移植术后受体微嵌合现象（microchimerism）的存在及其与免疫耐受的相关性。方法 吻合血管同种异体大段股骨干移植术后不同时期进行X线和组织学切片检查，并对不同组织器官进行性别决定因子Y（Sry）半定量聚合酶链反应（PCR）分析。结果 实验组在术后不同时期的X线及组织学表现为典型的骨折愈合模式；对照组X线及组织学表现为密度增高的移植骨被大量骨痂包绕，以及畸形愈合等排斥反应征象。Sry半定量PCR分析显示，实验组术后器官组织的微嵌合发生率及嵌合率明显高于对照组，且随术后期的延长而增高。结论 吻合血管同种异体骨移植术后，受体的一些器官组织存在着微嵌合现象，且微嵌合发生率与受体对移植骨组织相容性呈正相关。     

荧光原位杂交方法分析肾脏移植物血管内皮细胞嵌合

目的 观察移植肾穿刺活检标本中血管内皮细胞被受体内皮细胞替代(内皮嵌合)的情况,并分析内皮嵌合与急性排斥反应的关系.方法 选择Y染色体长臂Yq12区域(异染色质区)DNA片段作为探针,同时选择X染色体着丝粒区(α卫星DNA)探针作为对照,通过在石蜡切片标本上进行间期细胞双色荧光原位杂交方法(FISH),分析34例男性供者、女性受者的移植肾穿刺活检标本的内皮嵌合现象,探讨其与排斥反应的关系.结果 肾脏移植物中血管内皮细胞嵌合现象较普遍存在,内皮细胞的分布呈灶状,供者内皮细胞和受体内皮细胞可相邻存在.血管内皮细胞嵌合的发生与排斥反应无明显相关性(P＞0.05).结论 FISH方法可用于研究性别错配移植受者中血管内皮细胞的起源,肾脏移植物中血管内皮细胞可以被受者来源的内皮细胞所替代,内皮细胞嵌合与排斥反应的发生无明显关系.     

肝移植患者外周血中Treg细胞上CTLA-4及HLA-DR表达的特征及意义

目的 观测肝移植患者外周血中调节性T细胞（Treg）上CTLA-4、HLA-DR分子的表达特征,探讨CTLA-4、HLA-DR表达与术后急性排斥反应的关系.方法 入组38例行肝移植术患者,其中16例患者发生急性排斥反应（急排组）,22例未发生急性排斥反应（稳定组）.应用流式细胞仪检测两组肝移植术后患者外周血中Treg细胞上CTLA-4、HLA-DR分子的表达,并分析其与肝功指标的相关性.结果 急排组外周血中Treg细胞上CTLA-4及HLA-DR分子表达水平明显低于稳定组（P＜0.05）.此外,Treg细胞上CTLA-4及HLA-DR分子表达水平与肝功指标ALT、AST呈明显负性相关.结论 肝移植患者发生急性排斥反应时,外周血中Treg细胞上CTLA-4及HLA-DR分子表达水平降低,提示其可能与术后急性排斥反应的发生相关.     

T细胞疫苗联合环孢素A抑制大鼠肝移植排斥反应实验研究

目的：研究特异性T细胞疫苗接种联合环孢素A（CsA）对大鼠肝移植排斥反应的抑制作用。方法：利用LOU／CN大鼠的脾细胞免疫CHN大鼠，取后者脾细胞活化所制备的T细胞疫苗对肝移植受体的CHN大鼠进行免疫，移植时联合CsA，以大鼠肝移植后的存活时间、混合淋巴细胞培养、微量细胞毒测定对该方法抗大鼠肝移植排斥反应的作用加在证实。结果：和对照组相比较，T细胞疫苗接种联合CsA使肝移植大鼠存活期明显延长（P＜0.01），淋巴细胞转化率等排斥反应指标也具有显著性差异（P＜0.01）。结论：T细胞疫苗接种联合CsA能显著延长异品系大鼠肝移植的存活期，有明显的抗排斥反应作用。     

慢性移植排斥反应诱导的小鼠肾炎发生因素的初步探讨

目的探究慢性移植排斥反应诱导小鼠肾炎的发生机制,为下一步药物治疗提供实验依据。方法建立DBA/2→B6D2F1（DBA/2J×C57BL/6）移植小鼠模型,通过尿蛋白检测以及组织病理学分析确定小鼠肾炎的发生;利用直接免疫荧光标记技术以及实时定量PCR分析慢性移植排斥反应诱导小鼠肾炎发生过程中T、B淋巴细胞的活化情况,以及靶组织器官中各种因子或蛋白的变化。结果与同系基因型移植对照组（B6D2F1→B6D2F1）小鼠相比,异体移植实验组（DBA/2→B6D2F1）小鼠脾细胞中CD4＋CD69＋、CD8＋CD69＋双阳性细胞百分比均明显增加,B220＋I-Ab＋双阳性细胞的I-Ab表达显著增强,提示T、B淋巴细胞的活化;另外,在实验组小鼠肾组织中,趋化因子如单核细胞趋化蛋白-1（MCP-1）、受激活调节正常T细胞表达和分泌因子（RANTES）、B淋巴细胞趋化因子（BLC）以及淋巴细胞趋化因子（Ltn）表达上升;炎性细胞因子（如IL-6、IL-1β）表达显著增强;促纤维生长因子如转化生长因子β1（TGF-β1）、结缔组织生长因子（CTGF）以及纤维增生相关蛋白如Ⅰ型胶原蛋白（collagenⅠ）的mRNA表达水平明显上升,提示组织炎症以及纤维化的发生。结论慢性移植排斥反应诱导肾炎发生可能与激活淋巴细胞以及炎症因子、趋化因子和促纤维生长因子的分泌表达有关。     

我国首例异体小肠移植粘膜活检组织病理学评价

经造口在内窥镜或肉眼直视下取移植物肠粘膜，共２４次。组织病理学表现为绒毛水肿，扁平上皮细胞空泡变性，绒毛顶端上皮与基底膜分离，绒毛顶端上皮变性脱落，固有腺体杯状细胞减少，固有层少量淋巴细胞，单核细胞散在。无血管炎及隐窝炎。肠移植２周以后肠粘膜膜损伤逐渐恢复。讨论了小肠移植肠粘膜活检的意义，活检的时间与方法及排斥反应的组织病理学标准。     

鼠—人嵌合抗体的研制及应用

应用重组ＤＮＡ技术，把人免疫球蛋白的恒定区基因与小鼠免疫球蛋白可变区基因相拼接，然后在真核生物细胞中进行表达，可生产出既能保持原有抗体的特异性，又能在人体内避免排斥反应的鼠－人嵌合抗体。     

鼠－人嵌合抗体的研制及应用

应用重组ＤＮＡ技术，把人免疫球蛋白的恒定区基因与小鼠免疫球蛋白可变区基因相拼接，然后在真核生物细胞中进行表达，可生产出既能保持原有抗体的特异性，又能在人体内避免排斥反应的鼠－人嵌合抗体。嵌合抗体因含有人抗体的Ｆｃ段，所以能有效地与人效应细胞上的Ｆｃ受体结合，诱导细胞毒性效应，延长在人体内的半衰期。因此，它将进一步有可能成为我们大量获得新一代低成本的重要途径。     

肾移植排斥反应155例的临床病理学研究

对１５５例移植肾标本进行了组织学，免疫荧光及免疫组化研究，其中超急性排斥２７例，急性排斥７４例，慢性排斥５４例，超急性排斥反应早期以肾间质小血管及肾小球毛细血管内大量红细胞淤滞为主要改变，急性排斥反应的变化为：（１）间质水肿，充血，出血，淋巴细胞，单核细胞浸润；（２）动脉内膜炎，全层炎及血管壁纤维样坏死；（３）肾小管上皮浊肿，变性，坏死，慢性排斥反应的移植肾的病理改变主要以增殖性改变为特性，研究认     

CTLA4-Ig诱导的免疫耐受及其在肝移植和肝细胞移植中的应用

排斥反应尤其是急性排斥反应一直是影响器官、组织、细胞移植成功与否的关键问题，肝移植和肝细胞移植亦不例外。目前解决排斥反应的主要策略是使用免疫抑制剂，但此类药物毒副作用较大，需长期甚至终身服用，增加感染和肿瘤的发生率。在此背景下，诱导移植物免疫耐受成为研究热点。众多研究发现，细胞毒性T淋巴细胞相关抗原4免疫球蛋白（cytotoxicT-lymphocyteassociatedantigen4-immunoglobulin，CTLA4-Ig）通过阻断T淋巴细胞活化的共刺激通路诱导移植物免疫耐受，具有良好的临床应用前景。笔者仅就CTLA4-Ig在诱导移植物免疫耐受中的作用、机制及其在肝移植和肝细胞移植中的应用作一简要综述。     

Small bowel diverticulitis: an imaging review of an uncommon entity

In this review, we discuss the clinical and radiologic findings of small bowel diverticulosis, which is infrequently encountered during practice and far less common than colonic diverticulosis. Small bowel diverticulosis can present with a range of emergent symptomatic complications including diverticulitis, perforation, or hemorrhage. Here, we focus on the clinical features, pathogenesis, radiologic findings, and treatment of small bowel diverticulitis. Although not routinely considered in the differential diagnosis of an acute abdomen, prospective radiologic diagnosis of small bowel diverticulitis is important and can lead to conservative treatment thus preventing unnecessary exploratory laparotomy.     

Embolotherapy for small bowel hemorrhage from metastatic renal cell carcinoma: Case report

Embolization for control of hemorrhage in the small bowel carries a significant risk of bowel infarction. A case is presented where severe gastrointestinal hemorrhage from a hypervascular renal cell carcinoma metastasis to the jejunum was effectively controlled by superselective embolization of mesenteric tumor supply arteries with Gelfoam particles. Adjacent normal mesenteric arteries remained open. It is concluded that in specific instances where direct mesenteric feeders to a tumor can be catheterized, such embolization can be performed safely.     

CT enteroclysis: technique and clinical applications

CT enteroclysis (CTE) has been gradually evolving with technical developments of spiral and multidetector row CT technology. It has nowadays become a well-defined imaging modality for the evaluation of various small bowel disorders. Volume challenge of 2L of enteral contrast agent administrated to the small bowel via a nasojejunal catheter ensures luminal distension, the prerequisite for the detection of mural abnormalities, also facilitating the accurate visualization of intraluminal lesions. CT acquisition is centered on small bowel loops, reconstructed in thin axial slices and completed by multiplanar views. Image analysis is essentially done in cine-mode on work-stations. CTE is of particular diagnostic value in intermediate or advanced stages of Cohn's disease, including the depiction of extraintestinal complications. It has become the imaging modality of choice for the localization and characterization of small bowel tumors. The cause and degree of low-grade small bowel obstruction is more readily analyzed with the technique of CTE than conventional CT. Limitations of CTE concern the assessment of pure intestinal motility disorders, superficial mucosal lesions and arteriovenous malformations of the small bowel, which are not consistently visualized. CTE should be selectively used to answer specific questions of the small bowel. It essentially contributes to the diagnostic quality of modern small bowel imaging, and therefore deserves an established, well-defined place among the other available techniques.     

热休克蛋白70与大鼠小肠移植后急性排斥反应的实验研究

 目的 探讨热休克蛋白(HSP)70在大鼠小肠移植后急性期排斥反应中的作用.方法 建立SD大鼠到Wistar大鼠(异基因移植组)、Wistar大鼠到Wistar大鼠(同基因移植组)异体并列式小肠移植模型,应用免疫组织化学S-P法检测术后第1、4、7天肠标本HSP70表达,常规病理HE染色判定移植小肠的免疫排斥反应分级.结果 术后第7天,异基因移植组HSP70的表达高于同基因移植组;且HSP70的表达高者,小肠免疫排斥反应程度重.结论 HSP70与大鼠小肠移植后急性排斥反应有关,对急性排斥反应的早期诊断有参考价值.     

Incisional hernia and small bowel obstruction following laparoscopic surgery: computed tomography diagnosis

Incisional hernias are a relatively uncommon complication of laparoscopic surgery. Early CT diagnosis of small bowel obstruction due to incarceration in an incisional hernia after laparoscopic cholecystectomy enabled early surgery to be carried out, thereby preventing gut ischaemia and resection.     

Dynamic computed tomography of angioedema of the small bowel induced by iodinated contrast medium: prompted by coughing-related motion artifact

Small bowel angioedema is a rare adverse effect of iodinated contrast medium. Here, we report the first case of contrast medium-induced small bowel angioedema with concurrent respiratory tract symptoms. A patient with colon cancer underwent CT scanning for preoperative staging. After injection of the contrast medium, a persistent cough developed and CT images showed that the small bowel wall was abnormally thickened. It returned to normal by the follow-up. The persistent coughing that developed right after the CT and small bowel wall thickening on the contrast-enhanced CT suggested the diagnosis of small bowel angioedema induced by the contrast medium.     

Chest radiography in infant cardiac allotransplantation

Heart transplants were performed in seven infants at Loma Linda University Medical Center from 1985 to 1987. Five of these seven patients survived. In this report, the radiographic appearance of the chest is presented before surgery, immediately after surgery, and during a documented episode of rejection. The most current available chest radiograph is also presented. Acute rejection was confirmed by clinical, echocardiographic, and ECG findings. The only pulmonary infection encountered was mycoplasma pneumonitis. Four patients developed gastrointestinal rotavirus infections and were shown to have dilated proximal small-bowel folds on upper gastrointestinal studies. At the time of this writing, the prognosis for the five surviving infants is good. We conclude that the radiographs of infants who have received heart transplants show an unusual cardiac contour and slight cardiomegaly. Increasing cardiomegaly can alert one to early rejection. Prominent folds in the small bowel are of uncertain origin and significance, but they may be related to infection resulting from immunosuppression.     

Capsule enteroscopy and radiology of the small intestine

In a very few years, the video capsule for small bowel enteroscopy has gained widespread clinical acceptance. It is readily ingested, disposable, and allows for a complete, low-invasive endoscopic examination of the entire mucosa of the small bowel. It is a patient-friendly method and a first-line procedure in the difficult evaluation of obscure gastrointestinal bleeding. It has the highest proven figure of diagnostic sensitivity for detecting lesions of the mucosa, irrespective of aetiology. The limitations of capsule endoscopy include difficulty in localising mucosal lesions anatomically and its restricted use in patients with dysphagia, strictures or motor dysfunction. Strictures, transmural and extra-mural lesions in patients with small bowel Crohn’s disease are evaluated by MRI- enterography and CT-enterography.     

Percutaneous decompression of the bowel with a small-caliber needle: a method to facilitate percutaneous abdominal access

OBJECTIVE: In our pediatric interventional practice, we have found that occasionally a loop of bowel is interposed between the stomach and the anterior wall of the abdomen, preventing safe needle access for procedures such as placement of a gastrostomy tube. The use of a small-caliber needle to aspirate air from the colon or small bowel, for bowel decompression, may be a safe way to aid in establishing a safe access route for the subsequent percutaneous introduction of larger needles or tubes. CONCLUSION: Our retrospective review of patients who have undergone bowel-gas aspiration during an interventional procedure shows that the aspiration of air from the colon with a small-caliber needle is technically easy and may permit completion of an abdominal procedure.     

Tc HMPAO-labelled white cell scintigraphy in Cr?hn's disease of the small bowel.

99mTechnetium-hexamethyl propylene amine oxime (99mTc HMPAO) white cell scintigraphy is increasingly used in the investigation of inflammatory bowel disease. It is now an accepted technique in the assessment of patients with colitis, although its role in small bowel is less clear. A retrospective study was performed on patients with jejunal and ileal Cr?hn's disease to assess the sensitivity, reliability and usefulness of this technique in small bowel disease. Tc HMPAO scintigraphy was compared with barium studies, clinical outcome and, where available, subsequent histology. Good correlation between this technique and barium studies was found in 14 out of 18 patients and additional information was provided in two patients. A single false positive scan highlights the importance of early scanning in avoiding errors of interpretation due to the normal hepatobiliary excretion of activity that occurs with this pharmaceutical.