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961.
目的研究乳酸菌对慢性肾衰竭大鼠的肠粘膜通透性及中小分子尿毒素清除的影响。方法40只SD大鼠分为正常对照组(10只)行假手术,30只作5/6肾切除后分为肾衰竭病理对照组、双歧杆菌治疗组和乳酸杆菌治疗组。喂养1周后处死动物留取血粪标本。用紫外线吸收法测定血/粪中分子物质(MMS)。尿素(UN)和肌酐(Cr);用酶偶联紫外分光度法检测血D-乳酸。结果病理对照组血、粪MMS和UN、Cr均升高(P〈0.01);血浆D-乳酸含量增高(P〈0.01)。双歧杆菌治疗组和乳酸杆菌治疗组较病理对照组的血浆D-乳酸含量降低(P〈0.01);BUN、SCr均降低(P〈0.01);而粪UN、Cr均增加(P〈0.01)。结论双歧杆菌和乳酸杆菌均可维持慢性肾衰竭大鼠肠粘膜正常通透性,加速肠道清除MMS,分解肠道内尿素和肌酐降低其血中的浓度。  相似文献   
962.
为提高对婴儿隐匿性原发性小肠淋巴管扩张症的临床、内镜及病理特点的认识,减少漏诊及误诊,我们对厦门市儿童医院收治的1例原发性小肠淋巴管扩张婴儿的临床表现和诊疗相关资料进行了回顾性分析。该例患儿以支气管肺炎收住入院,轻度腹泻和水肿,未见外周血淋巴细胞数减少,呈现低蛋白血症。输注白蛋白未能缓解低蛋白血症,随后胃镜检查显示十二指肠段可见大小不等密集的白色粟粒样颗粒状隆起,黏膜呈广泛白斑样病变,病理检查显示明显的小肠淋巴管扩张,进而确诊小肠淋巴管扩张症。确诊后每两日输注白蛋白,连续输注两个疗程并予portagen中链脂肪酸奶粉喂养。经处理后血浆中总蛋白和白蛋白基本升至正常水平,腹部及胸部彩超显示双胸腔及双肺积液均已被吸收。对该病例的回顾性分析结果表明对于有血浆白蛋白及球蛋白下降而导致浮肿的婴儿,排除肝肾疾患及肿瘤、结核等慢性疾病所致蛋白消耗过多的可能性,均应考虑小肠淋巴扩张症,需尽可能尽早行胃镜检查,进一步完善病理活检,实现早日确诊、尽早进行对症治疗及饮食干预治疗,避免处理不及时导致的严重后果。  相似文献   
963.
Objective: Cerulein and neostigmine are prokinetic drugs whose potency and effective dose range are barely known. The aim of this study was to assess their benefit for normal and compromised peristalsis. Design: In vitro, isolated segments of guinea pig small intestine. Setting: University laboratory. Interventions: Small bowel segments were mounted in tissue baths and luminally perfused with Tyrode solution. Test drugs (prokinetic: cerulein, neostigmine; inhibitory: atropine, hexamethonium, epinephrine, sufentanil) were added to the tissue bath. Measurements and results: Peristalsis was quantified via changes in the peristaltic pressure threshold. One-way and two-way analysis of variance (ANOVA) were used for statistical analysis. Cerulein (0.03–100 nM) stimulated normal peristalsis in a concentration-dependent manner and reversed paralysis of peristalsis induced by all inhibitory test drugs to a similar extent. The properistaltic effect of neostigmine was limited to a narrow concentration range (0.03–0.1 µM), whereas concentrations >0.3 µM inhibited peristalsis. Neostigmine more effectively counteracted blockage of peristalsis caused by atropine than that caused by hexamethonium. The inhibitory effects of epinephrine and sufentanil on peristalsis were reversed only at the concentration range of 0.1–0.3 µM neostigmine. Conclusions: Cerulein stimulates normal peristalsis in vitro at a wide concentration range and reverses blockage of peristalsis caused by drugs with a site of action either on the enteric nervous system or intestinal smooth muscle. Neostigmines prokinetic effect, to the contrary, is limited to a small concentration range and best seen when peristalsis is depressed by blockage of cholinergic muscle activation.  相似文献   
964.
The aim of the study was to ascertain whether there is an association between the presence of serum parietal cell autoantibodies (PCA) and: (1) Helicobacter pylori infection; (2) the presence and degree of gastritis and intestinal metaplasia; and (3) the H. pylori infecting strain. Gastric mucosal biopsies were obtained from 49 consecutive patients in order to assess and grade gastritis, make a histological diagnosis, and culture and genotype H. pylori. H. pylori infection was present in 26 patients (group 1), had been present in 17 patients (group 2), and the remaining 6 (group 3) had never had the infection. The infecting strain was cagA positive in 21 of 26 group 1 patients. Positive PCA results were found in 84%, 76%, and 14% of patients in groups 1, 2, and 3, respectively. PCA results were correlated with anti-H. pylori antibody titers (P<0.05). In group 2 patients, PCA were associated with the degree of antral gastritis (Fisher's exact test P<0.05). cagA status was not associated with the presence of PCA (chi2=0.68, NS). The frequency of positive findings for PCA in group 2 was higher in patients with (90%) than in those without (50%) intestinal metaplasia. In conclusion: (1) H. pylori infection is associated with the production of PCA, which, after eradication of the infection, persist and might contribute to the persistent antral chronic gastritis and intestinal metaplasia; (2) the gastric lesions associated with infections sustained by the more-virulent H. pylori strains do not appear to be due to the induction of antigastric autoantibodies.  相似文献   
965.

Purpose

To compare the technical success and complication rates of push versus pull gastrostomy tubes in cancer patients, and to examine their dependence on operator experience.

Materials and methods

A retrospective review was performed of 304 cancer patients (170 men, 134 women; mean age 60.3 ± 12.6 [SD], range: 19–102 years) referred for primary gastrostomy tube placement, 88 (29%) of whom had a previously unsuccessful attempt at percutaneous endoscopic gastrostomy (PEG) placement. Analyzed variables included method of insertion (push versus pull), indication for gastrostomy, technical success, operator experience, and procedure-related complications within 30 days of placement.

Results

Gastrostomy tubes were placed for feeding in 189 patients and palliative decompression in 115 patients. Technical success was 91%: 78% after endoscopy had previously been unsuccessful and 97% when excluding failures associated with prior endoscopy. In the first 30 days, there were 29 minor complications (17.2%) associated with push gastrostomies, and only 8 minor complications (7.5%) with pull gastrostomies (P < 0.05). There was no significant difference in major complications (push gastrostomy 5.3%, pull gastrostomy 5.6%). For decompressive gastrostomy tubes, the pull technique resulted in lower rates of both minor and major complications. There was no difference in complications or technical success rates for more versus less experienced operators.

Conclusion

Pull gastrostomy tube placement had a lower rate of complications than push gastrostomy tube placement, especially when the indication was decompression. The technical success rate was high, even after a failed attempt at endoscopic placement. Both the rates of success and complications were independent of operator experience.  相似文献   
966.
目的 比较标准心肺复苏、主动按压减压心肺复苏、主动按压减压结合高频通气心肺复苏三种复苏法对心肺复苏循环效应影响 ;评价主动按压减压结合高频通气用于心肺复苏的可行性。方法 将9条犬经电击致颤制成心搏骤停模型 ,每只犬先后实施三种复苏法 ,①标准心肺复苏 ;②主动按压减压心肺复苏 ;③主动按压减压结合高频通气心肺复苏 ,实验顺序由随机法确定 ,每种复苏方法进行 5min ,待循环动力学稳定后记录收缩压、舒张压、心输出量。结果 收缩压、舒张压、心输出量均为主动按压减压结合高频通气模式大于主动按压减压心肺复苏模式 (P <0 0 1) ;主动按压减压心肺复苏模式大于标准心肺复苏模式 (P <0 0 1)。标准心肺复苏模式和主动按压减压心肺复苏模式胸外按压停顿期血压降至零 ,而主动按压减压结合高频通气心肺复苏模式血压持续稳定。结论 主动按压减压心肺复苏优于标准心肺复苏模式。主动按压减压结合高频通气心肺复苏模式既可产生较高的动脉血压、心输出量 ,又可提供充分的气体交换 ,值得进一步研究和推广应用  相似文献   
967.
Real-time ultrasonography can detect the movement of viscera immediately deep to the abdominal wall. This motion of abdominal contents is called viscera slide, and is produced by the force of respiratory motion (spontaneous viscera slide) or by manual ballottement of the abdomen (induced viscera slide). Viscera slide was observed in 18 "normal" subjects (no history of previous abdominal surgery or peritonitis) and in 24 subjects at "risk" for abdominal wall adhesions because of previous abdominal operations or past history of peritonitis. In 14 of the 24 "risk" group subjects, spontaneous and induced viscera slide was restricted to excursions of less than 1 cm (58.3%). Operations were performed on 18 patients, which confirmed the fact that restriction of ultrasonically detected viscera slide identified abdominal wall adhesions in all cases, but no adhesions were found in patients with normal viscera slide. This ultrasonic finding of restricted viscera slide may be useful in the preoperative discovery and localization of abdominal wall adhesions prior to laparoscopy or laparotomy.  相似文献   
968.
先天性肠系膜裂孔疝外科治疗5例并文献复习   总被引:1,自引:0,他引:1  
陈锋 《中国误诊学杂志》2005,5(10):1814-1816
目的:探讨先天性肠系膜裂孔疝的早期诊断和治疗方法。方法:回顾性分析经手术证实的5例患者临床资料。结果:5例均行急诊手术,术中确诊。4例行小肠部分切除术,1例发病4h手术,复位成功,1例术后出现短肠综合征。结论:腹部X线和腹穿有助于诊断。早期诊断,及时手术是治疗先天性肠系膜裂孔疝的关键。  相似文献   
969.
Background Gastrointestinal stromal tumors (GISTs) are characterized by the expression of c-KIT (antigen CD 117) and are the most common mesenchymal tumors of the digestive tract. An important complication, although infrequently described in the literature, is the rupture of these tumors with accompanying hemoperitoneum. Methods We performed a retrospective evaluation of the clinical history and radiologic records of 23 patients with a diagnosis of GIST and anatomopathologic and immunohistochemical confirmation at our hospital between 1999 and 2004. Results In five cases there was rupture of the primary tumor (four gastric and one jejunal). In all five cases ultrasonographic and computed tomographic examinations showed a heterogenic tumor of laminated or whirled appearance, associated with echogenic or dense ascites. No relation was found between histologic criteria of malignancy and the rupture. Four patients underwent surgical intervention, three of them urgently. Two of five patients died. There was a sixth case with rupture of a hepatic metastasis, with accompanying hemoperitoneum and subcapsular hematoma. This patient died at 3 months, after recurrence of bleeding. Conclusions The finding of a heterogeneous tumor of laminated or whirled appearance associated with ascites with characteristics compatible with hemoperitoneum in an appropriate context must lead to a suspicion of the existence of a ruptured GIST.  相似文献   
970.
目的:通过观察阳明病(阳明腑实证)模型大鼠"欲解时"血常规及肠黏膜上有关炎症因子的变化,初步探讨阳明病"欲解时"的病理生理学基础。方法:实验大鼠随机分为欲解时对照组、欲解时模型组、非欲解时对照组、非欲解时模型组,建立阳明腑实证大鼠模型后,分别于阳明病"欲解时"及"非欲解时"每天取血及肠组织,连续5d,血细胞分析仪检测血常规,免疫组化法测Toll样受体4(TLR4)蛋白含量,荧光实时定量聚合酶链反应(PCR)检测肠组织TLR4 mRNA水平。结果:欲解时模型组大鼠白细胞、中性粒细胞、单核细胞数较非欲解时模型组升高,其中单核细胞数上升差异有统计学意义(P<0.05);模型组淋巴细胞显著低于对照组(P<0.05)。欲解时模型组TLR4 mRNA及蛋白较非欲解时模型组显著降低,第1天TLR4 mRNA相对表达量差异有统计学意义(P<0.05)。结论:阳明腑实证病程中,欲解时模型组大鼠中性粒及淋巴细胞较对照组体现出较早较长时间的差异性,意味着欲解时的免疫反应更为明显。通过TLR4检测表明欲解时阳明腑实证的炎症反应较非欲解时轻,可能与其表达下调相关炎性介质的释放减少有关。  相似文献   
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