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71.
72.
延髓损伤可能会引发局限型和广泛型急性胃粘膜出血   总被引:13,自引:0,他引:13  
目的:通过动物实验,观察延髓损伤引起胃粘膜出血的表现形式和特点。方法:对19只成年健康杂种狗,进行延髓一侧性损伤手术(13只)和对照假损伤性手术(6只);在损伤后,对胃粘膜表现进行胃镜的动态观察。结果:延髓损伤,可引起胃粘膜出血,而且发生率很高,达100%;胃粘膜出血的严重程度及其预后有轻、重不同。结论:分析观察结果后认为:胃粘膜出血分可能有局限型和广泛型两个类型;延髓损伤的严重程度与胃粘膜出血的类型密切相关。  相似文献   
73.
Hemolytic uremic syndrome (HUS) consists of an acute onset of microanglopathic hemolytic anemia, thrombocytopenia, and renal dysfunction. HUS-associated colitis can be seen in up to 100% of patients and is usually associated with severe abdominal pain and distention. Colonic perforation is a complication of HUS that has a reported incidence of 1%–2%, and although there are several case reports in the literature describing perforation of the colon, it is still very difficult to discern the abdominal symptoms associated with HUS colitis from perforation. Four cases of colonic perforation are reported here from a consecutive series of 57 patients, in which a trend in the length of time from the onset of symptoms of HUS to colonic perforation was determined. A review of the literature for cases of HUS-associated colonic perforation was also performed. The time from the onset of HUS symptoms to colonic perforation in our series was similar to that found in the literature review (11 ± 5 vs 14 ± 8 days). Awareness that this complication has a tendency to occur towards the end of the 2nd week during the course of HUS is essential to avoid an unnecessary and untimely surgical intervention. Accepted: 25 June 1997  相似文献   
74.
In order to demonstrate the involvement of nitric oxide synthases (NOS) – in particular the inducible isoform (iNOS) – in inflammatory processes within the nasal airways, we used organ-bath incubation to study isolated inferior turbinates and mucosa of the maxillary sinus of guinea pigs. The pattern of the expression in various substructures of the nasal mucosa was of special interest. Mucosa was incubated for 6 h with lipopolysaccharides (LPS) produced by E. coli, interleukin II (IL-2) or tumor necrosis factor-alpha (TNF-α). Saline was used as the control solution. Following incubation the specimens were fixed in buffered 4% formaldehyde solution over a period of 4 h. Tissues were next exposed to nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase-reaction and immunostained with specific antibodies to iNOS. Results then showed a clearly increased or initiated expression of iNOS in epithelium, glands, leucocytes and blood vessels of treated tissues in comparison to the control specimens. The inflammatory mediator LPS and the cytokines Il-2 or TNF-α alone were found to be capable of increasing the expression of iNOS, although the effects of LPS clearly exceeded those of the cytokines. This finding implicates iNOS-generated nitric oxide as a key factor for causing nasal swelling, secretion and obstruction during nasal infections and allergic episodes. Received: 18 November 1997 / Accepted: 22 April 1998  相似文献   
75.
再次尿道成形术治疗先天性尿道下裂术后严重并发症   总被引:43,自引:3,他引:43  
目的:了解先天性尿道下裂行各种尿道成形术失败后,利用膀胱粘膜行尿道成形术的疗效。方法:将严重狭窄和(或)无法修补的尿瘘瘢痕组织彻底切除,取膀胱粘膜片形成尿道,正位开口于龟头,新尿道内置多孔硅胶支架管作引流。结果:28例中,23例治愈,3例有小尿瘘需作尿瘘修补,2例完全失败,再次作粘膜尿道成形术治愈。结论:各种类型先天性尿道下裂尿道成形失败后,可用膀胱粘膜移植尿道成形,效果良好  相似文献   
76.
大鼠腹主动脉注入1%墨汁硝酸银溶液,可同时显示小肠淋巴管和微血管,浆膜下注入10%ABS丁酮溶液可制成小肠粘膜淋巴管的铸型标本,用光镜和SEM观察,利用图像分析仪测量了肠粘膜淋巴管的数量、管径、长度等。小肠粘膜初始淋巴管数为275±52/mm2,管径为349±40μm,长度为2085μm,初始后淋巴管管径为349+40μm,长度1074μm,提出了区分初始淋巴管和初始后淋巴管的依据,获得了有关汇合淋巴管、粘膜下层淋巴管网数、园形因子等数据,小肠不同区段如十二指肠、空肠、回肠、淋巴管的上述数据有某些差别。我们的研究结果加深了对大鼠小肠淋巴管的分布、走行和形态等的认识  相似文献   
77.
目的 :了解鼻息肉 (NP)中一氧化氮合酶 (NOS)的分布特点和活性及其在NP发病中的作用。方法 :用免疫组织化学法检测 30例NP(NP组 )及 2 0例正常鼻黏膜 (正常鼻黏膜组 )中NOS的表达 ,并用分光光度计法检测其活性。结果 :NP组NOS活性为 (4.0 79± 0 .6 5 5 )U/mg蛋白 ,正常鼻黏膜组为 (1.5 2 6± 0 .310 )U/mg蛋白 ,二者间差异有统计学意义 (P <0 .0 1) ;NP组iNOS有大量细胞表达 ,分布在黏膜上皮、腺体和血管内皮细胞以及炎症细胞中 ,与正常鼻黏膜组比较 ,差异有统计学意义 (P <0 .0 1) ;而eNOS也有表达 ,但与正常鼻黏膜组比较 ,差异无统计学意义 ;NP组i NOS表达明显高于eNOS表达 ,其差异有统计学意义 (P <0 .0 1)。结论 :NP主要表达iNOS ,分布在黏膜上皮、腺体和血管内皮细胞以及炎症细胞中 ,其产生的大量一氧化氮在NP的发病过程中可能起着重要的作用  相似文献   
78.
Further experience with seromuscular colocystoplasty lined with urothelium   总被引:1,自引:0,他引:1  
PURPOSE: We report our continuing experience with seromuscular colocystoplasty lined with urothelium. This procedure is designed to preserve the urothelium and potentially decrease the incidence of complications associated with standard bladder augmentation. MATERIALS AND METHODS: We retrospectively reviewed the charts of 32 patients who underwent seromuscular colocystoplasty lined with urothelium between April 1994 and July 1999. Data were collected on patient demographics, surgical indications, previous and adjunctive surgical procedures, preoperative and postoperative urinary continence, upper urinary tract changes, urodynamic parameters, surgical complications and histological findings. RESULTS: Mean patient age at surgery plus or minus standard deviation was 11.1 +/- 4.8 years. Mean followup was 1.6 +/- 1 years. A mean of 1.5 +/- 0.9 years postoperatively urodynamic studies available in 28 cases showed that total and safe bladder capacity increased by 1.8 and 2.4-fold, respectively. Continence was achieved in 71% of patients after the initial procedure, increasing to 81% after secondary procedures. Hourglass deformity developed in 7 cases (22%), augmentation failed in 4 (12.5%) and there were bladder calculi in 2 (6%). New onset or increased hydronephrosis and reflux were present in 6 of 62 (10%) and 9 of 60 (15%) evaluated renal units, respectively. Of the 7 interpretable biopsies 5 revealed various degrees of repeat colonic mucosal growth. There was no bladder perforation or metabolic abnormalities, and mucous production was not clinically significant. CONCLUSIONS: Seromuscular colocystoplasty lined with urothelium is a viable alternative to standard bladder augmentation. The 2 procedures have a similar overall complication rate. Comparatively there appears to be a low incidence of bladder calculi, mucous production has not been clinically significant, metabolic disturbances have not developed and perforation has not occurred during short-term followup. We are enthusiastic about this technique and continue to apply it in select patients.  相似文献   
79.
刘衡  王春龙 《药品评价》2004,1(2):132-134
介绍了口腔颊粘膜给药系统,并对其制剂的粘附力、粘附时间、膨胀率、均匀度和有效性等质量评价方面进行了综述。作为新型给药系统,颊粘膜给药系统的成熟与发展还需要在质量评价等方面进行深入研究。  相似文献   
80.
无水乙醇肠黏膜处理的实验研究   总被引:1,自引:0,他引:1  
目的:观察无水乙醇处理大鼠肠黏膜的远期结果。方法:以无水乙醇浸泡0.5 m in、1 m in或无水乙醇涂抹0.5 m in、1 m in,四种方案处理大鼠小肠黏膜。在大鼠膀胱扩大术模型中观察处理后肠段组织学的变化;在大鼠代膀胱模型中观察处理后肠段黏膜功能的变化。结果:以无水乙醇浸泡0.5 m in、1 m in或无水乙醇涂抹1 m in处理后5月,肠段发生了明显纤维化和不同程度皱缩;无水乙醇涂抹0.5 m in处理后的肠段没有皱缩,肌层纤维化不明显。无水乙醇涂抹0.5 m in处理后1月,代膀胱内黏液残留量明显减少,与对照组比较差异有统计学意义(P<0.01),处理后2月~5月,与对照组比较差异无统计学意义(P>0.05);处理后1月和5月,代膀胱黏膜对水、电解质的分泌或吸收量与对照组比较,差异无统计学意义(P>0.05)。结论:无水乙醇组织穿透力强,容易在肠黏膜处理的同时损伤大鼠肠段肌层,大于0.5 m in的处理将造成处理后肠段纤维化。无水乙醇涂抹0.5 m in不损伤肠壁肌层的适度处理,只能在术后早期减少黏液的分泌量,不能改变肠黏膜远期的分泌和吸收功能。  相似文献   
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