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91.
Objective Superantigens are potent inflammatory stimuli which derive from pathogenic microbes such as bacteria, viruses and protozoa. The aim of this study was to investigate the role of superantigens on the function of rabbit maxillary sinus epithelium. Methods Twenty New Zealand white rabbits were divided into 4 groups. Rabbit sinus mucosa was separated under a surgical microscope and mounted in Ussing chambers to record short circuit current, conductance and permeability to horseradish peroxidase (HRP). Group A was used as normal control. Group B was stimulated with an injection of superantigen into the sinus for 4 hours. The sinus mucosa of Group C was stimulated by the addition of tumor necrosis factor α (TNF-α) into Ussing chambers. Group D sinus mucosa was stimulated by superantigen after pretreatment with anti-TNF-α antibody. Results Superantigen evoked increases in sinus epithelial cell baseline short circuit current, conductance and permeability to HRP stimulated by the addition of TNF-α into Ussing chambers. These were similar to results from superantigen stimulation in vivo. The effect of superantigen on sinus epithelial cells could be blocked by pretreatment with anti-TNF-α antibody. Conclusions Superantigen affected the function of sinus epithelial cells, including the capability of epithelial defensive barrier, which might be mediated by TNF-α.  相似文献   
92.
胸腺肽对肠梗阻细菌移位的影响   总被引:8,自引:2,他引:6  
目的:通过对大鼠机械性肠梗阻模型细菌移位的实验研究,了解应用胸腺肽后,大鼠肠梗阻致细菌移位的改变情况,探索减少细菌移位的可能药物。方法:雄性SD大鼠30只,随机分为假手术组,肠梗阻组和胸腺肽组。检测肝脏和肠系膜淋巴细菌移位情况、血浆内毒素水平和进行回肠病理学检查等。结果:细胞移位率和细菌移位数水平,肠梗阻组和假手术组相比,明显升高,胸朱肽组和肠阻组相一少,血浆内毒素水平,胸腺肽组与肠梗阻组相比明显  相似文献   
93.
目的 :探讨空腹胃液、胃粘膜组织总胆汁酸 (TAB)的含量对胆汁返流性胃炎的诊断价值。方法 :对 47例胆汁返流性胃炎 (RG)组 ,15例消化性溃疡 (PU)组 ,2 0例慢性浅表性胃炎 (CSG)组及 12例正常对照组在胃镜检查的同时 ,抽取胃液 ,钳取胃粘膜组织作 TBA含量测定。胃粘膜组织同时作 HP及病理组织学检查。结果 :胆汁返流性胃炎组胃液及胃粘膜组织 TBA含量分别为 (315 .85 5 0± 35 .946 8)μm ol/ L ;(0 .2 10 7± 0 .0 810 )μmol/ g。明显高于 PU、 CSG及正常对照组 (P <0 .0 0 1)。胃粘膜组织 TBA含量与胃液 TBA含量呈明显正相关 ,rs=0 .82 8,P <0 .0 0 1。胃粘膜的炎症程度也随 TBA含量的增加而加重。χ2 =15 .6 37,P <0 .0 0 5。随着 TBA含量的增加 ,HP的检出率下降 ,χ2 =9.42 ,P <0 .0 1。结论 :胃液、胃粘膜组织 TBA含量对胆汁返流性胃炎有诊断价值。而胃粘膜组织 TBA含量更有价值。  相似文献   
94.
目的 探讨心脏直视术后危重患氧供需平衡的重要性和临床价值。指导救治,三疗效及预后,预防多器功能衰竭(MOF)的发生,使ICU监测水平跨跃到细胞水平。方法 对148例,心脏直视术后危重入ICU后,分阶段动态监测动脉,混合静脉血气,心输出量,胃粘膜PH值,对代谢这各项监测值之间相关关系进行分析。结果 动静脉血气及其差值的变化与循环,呼吸功能变化呈正在关系;APACHEⅡ评分高,SvO2低的极重患  相似文献   
95.
In a methodological survey, the technical prerequisites for optimal histopathological diagnosis of gut dysganglionosis are presented. To make a proper diagnosis, the pediatric surgeon or gastroenterologist and the pathologist must consider certain preconditions. The most important steps for the optimal biopsy diagnosis of an aganglionosis, an ultrashort Hirschsprung segment, a intestinal neuronal dysganglionosis (IND), a ganglioneuromatosis, a hypogenesis, or immaturity of the vegetative gut innervation are: (1) taking 3–4 biopsies the size of a peppercorn (3–5 mm3) with submucosa; (2) the best instruments for taking rectal mucosal biopsies are forceps and scissors or a conventional large biopsy forceps; and (3) biopsies may be taken 1 cm, 3–4 cm, 6–9 cm, and 9–12 cm (or from a preternatural anus) above the pectinate line. A biopsy containing mucosa, muscularis mucosae, and submucosa guarantees a satisfying histopathological diagnosis. The native biopsies can be transported on water-ice if the distance to the pathologist takes no longer than 4–6 h. For long distances, biopsies have to be frozen on dry ice (CO2 –80 °C) and transported in a sufficient amount of dry ice (adapted to the time of transportation). For biopsy processing, the following points are important: a total of 122 to 160 15-m-thick native cryostat serial sections have to be cut per biopsy and distributed on four microscope slides. Forty sections are used for lactic dehydrogenase reactions, 32 for succinic dehydrogenase reactions, and the rest for an acetylcholinesterase (AChE) reaction. An AChE reaction alone is sufficient for the diagnosis of Hirschsprung's disease (HD), but never for IND or other developmental malformations of the submucous and myenteric plexuses. Enzymehistotopochemical reactions allow the assessment of functional parameters. These reactions, in contrast to immunohistochemical staining, offer information about the functional activity of special gut structures, e. g., increased AChE activity in nerve fibers of the rectal wall in HD or a lack of dehydrogenase activity in immature ganglia.  相似文献   
96.
Previous studies have shown that transplantation of fetal rat small bowel into the greater omentum of adult recipient animals can be successfully carried out. However, the surface area of the omentum limits the length of implantable fetal small bowel. Furthermore, clinical experience has shown that due to adhesions, the greater omentum is no longer suitable as an implantation site after multiple laparotomies, which often precede a short-bowel syndrome. We wanted to examine whether recipient mesentery is a further possible site of fetal gut implantation. Four weeks after transplantation of the fetal graft into the mesentery of adult rats, mature intestine was found in 80% of the animals. Macroscopically, the developed transplants looked like bowel duplications"; light-microscopic examinations documented their morphologic integrity.  相似文献   
97.
通过对成都市七区两县监测点中2616例肠癌死亡率的统计学分析,总死亡率为7.00/10万,标化死亡率为6.67/10万(其中,大肠癌死亡1674例,占肠癌死亡例数构成比64%,其总死亡率4.88/10万,标化死亡率4.27/10万),均呈逐年上升趋势。男性死亡率7.67/10万,标化死亡率7.29/10万,女性死亡率6.29/10万,标化死亡率6.00/10万,男性明显高于女性(P<0.01);城区死亡率9.30/10万,郊(区)县死亡率4.94/10万,二者有显著性差异,城区高于郊(区)县(P<0.01);在2616例肠癌死亡例数中,工人、农民、干部、离退休人员占82.65%,且以45岁以上的男性居多。  相似文献   
98.
Intestinal transplantation (ITx) is the only curative treatment option for children with irreversible intestinal failure (IF) and complications of parenteral nutrition (PN). ITx is an immunologically difficult transplant due to the immune load of the donor gut; therefore, main causes of death and graft loss are immunological complications like sepsis or acute and chronic rejection. This article aims to help paediatricians in training understand when children should be referred for ITx, the different types of ITx, the complications these children might present with, and to learn about the journey a candidate for ITx must take with the support of the IF and ITx multidisciplinary teams (MDT).  相似文献   
99.
目的:探讨左半结肠急性梗阻如何安全实施一期切除吻合术。方法:回顾分析左半结肠急性梗阻行一期切除吻合术33例。结果:一期愈合31例,吻合口瘘1例,死亡率1例。结论:左半结肠急性梗阻只要正确掌握一期切除吻合术适应症,以及完善术中术后处理,可以安全施行一期切除吻合术。  相似文献   
100.
Congenital midgut malrotation, a rare anatomic anomaly that can lead to duodenal or small bowel obstruction, rarely is recognized beyond the first year of life. We report a case of unrecognized congenital midgut malrotation that resulted in midgut volvulus, causing intestinal obstruction and requiring emergent reoperation after laparoscopic cholecystectomy. This unusual complication, first reported in 1994, involved a 56-year-old man and resulted in cecal infarction recognized and treated on the second postoperative day. This second case describes a less acute postoperative course, with multiple bouts of partial bowel obstruction leading to two readmissions and finally resulting in a reexploration and definitive treatment on the 19th postoperative day. Received: 16 February 1999/Accepted: 22 March 1999  相似文献   
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