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目的:建立大鼠肢体火器伤合并海水浸泡模型,观察伤后愈合过程并分析影响愈合因素。方法:利用小型点爆源制造小鼠肢体火器伤模型,随机选取20只雄性Wistar大鼠,分为对照组及实验组,每组10只。制造肢体火器伤模型后对照组不浸泡,实验组伤后海水浸泡30min。观察记录伤后愈合过程,检测愈合过程中愈合时间、伤口面积、体重等指标变化及伤口愈合后的病理形态。结果:实验组伤口愈合时间较对照组晚;伤后相同时间点两组伤口面积存在差异;实验组创后早期显著体重下降,晚期体重平均增加量显著低于对照组;实验组伤口愈合后真皮层及皮下存在特殊病理学变化。结论:与单纯火器伤相比,火器伤合并海水浸泡可导致伤口延迟愈合。  相似文献   
23.
目的::比较光学生物学测量仪( IOL Master )、接触式和浸润式A超对前房深度( anterior chamber depth,ACD)的测量结果,分析三种测量方法是否存在差异及其一致性。方法:选取2013-07/10于我院诊断为年龄相关性白内障患者58例98眼术前分别进行IOL Master、接触式A超和浸润式A超的ACD测量,应用方差分析对三种方法的测量结果差异进行比较,应用Blant-Altman分析法比较其一致性。结果:IOL Master 测量 ACD 为2.31~3.90(平均3.03±0.38) mm;接触式 A 超测量 ACD 为1.51~4.06(平均2.88±0.56)mm;浸润式A超测量ACD为1.99~4.17(平均3.17±0.38)mm。 IOL Master和接触式A超的ACD测量值差异有统计学意义( P=0.022<0.05)。 IOL Master和浸润式A超ACD测量值差异有统计学意义( P=0.031<0.05)。接触式A超与浸润式A超ACD测量值差异有统计学意义(P=0.000<0.05)。三种方法相互间一致性均较差。结论:三种方法测量白内障患者ACD时,浸润式A超测得结果最大,IOL Master次之,接触式A超测得结果最小,三者相互间一致性均较差,临床不建议相互替代。  相似文献   
24.
BACKGROUNDStress-related gastric mucosal damage or ulcer remains an unsolved issue for critically ill patients. Stress ulcer prophylaxis has been part of routine intensive care, but uncertainty and controversy still exist. Co-secreted with mucins, intestinal trefoil factor (ITF) is reported to promote restitution and regeneration of intestinal mucosal epithelium, although the mechanism remains unknown.AIMTo elucidate the protective effects of ITF on gastric mucosa and explore the possible mechanisms.METHODSWe used a rat model of gastric mucosal damage induced by water immersion restraint stress and lipopolysaccharide-treated human gastric epithelial cell line to investigate the potential effects of ITF on damaged gastric mucosa both in vivo and in vitro.RESULTSITF promoted the proliferation and migration and inhibited necrosis of gastric mucosal epithelia in vitro. It also preserved the integrity of gastric mucosa by upregulating expressions of occludin and zonula occludens-1. In the rat model, pretreatment with ITF ameliorated the gastric mucosal epithelial damage and facilitated mucosal repair. The protective effects of ITF were confirmed to be exerted via activation of Akt signaling, and the specific inhibitor of Akt signaling LY249002 reversed the protective effects.CONCLUSIONITF might be a promising candidate for prevention and treatment of stress-induced gastric mucosal damage, and further studies should be undertaken to verify its clinical feasibility.  相似文献   
25.
Apelin has been identified as an endogenous ligand of the orphan G-protein-coupled apelin receptor (APJR). These receptors are widely expressed in the central nervous system and periphery and play a role in the regulation of fluid and glucose homeostasis, feeding behavior, vessel formation, cell proliferation and immunity. We aimed to investigate whether water immersion and restraint stress have effects on apelin and APJR expression and apoptosis in heart tissue of male Wistar rats. The cardiac tissues were obtained from control, water immersion and restraint stress (WIRS) and apelin antagonist (F13A) + WIRS groups of rats and embedded in paraffin wax. Immunohistochemical staining methods were used to localize apelin, APJR and TUNEL immunopositive cells. H-SCORE was used for semi-quantitative determinations. Apelin protein levels were determined by Western blot in the cardiac tissues and plasma corticosteroid levels were measured by enzyme immunoassay (EIA). Apelin immunolocalization was found especially in endothelial cells and mast cells and faintly in cardiomyocytes, APJR immunostaining was shown in endothelial cells and cardiomyocytes, and TUNEL reaction was observed in endothelial cells and in some fibroblasts. Apelin expression was significantly increased in the WIRS and F13A + WIRS groups compared to the control group. The APJR reaction was similar in all groups. The number of TUNEL-positive cells was significantly higher in the F13A + WIRS group than that of the control group. Our study showed that WIRS for 6 h increased plasma corticosterone levels and cardiac apelin expression in rats. The increased levels of apelin inhibited stress-induced apoptosis in heart. These results may be important for the therapeutic approach to a variety of stress-related heart disease.  相似文献   
26.
目的模拟海难落水所致重度低体温损伤,比较鉴定低温海水浸泡模型动物血浆蛋白质组差异,为研究低体温相关血浆蛋白提供线索。方法将50只雄性健康Wistar大鼠平均分成5组,分别在低温海水中浸泡0、2、4、6、10 h后采集下腔静脉血。分离血浆后,用试剂盒去除Ig G和白蛋白等高丰度蛋白,并经过除盐后采用蛋白质双向凝胶电泳(2-DE)分离。对差异1.5倍以上的蛋白斑点,用基质辅助激光解析电离飞行时间质谱(MALDI-TOF-MS)进行肽质量指纹图谱分析,应用NCBI或Swiss-prot数据库鉴定差异蛋白质。结果大鼠浸泡在15℃海水中,中心体温(肛温)迅速下降,浸泡30 min降至19℃,浸泡120 min降至16℃左右,体温维持不变,说明进入重度低体温状态。初步鉴定出3个与低温相关差异蛋白,肺表面相关蛋白A(SP-A)、丝氨酸蛋白酶抑制剂A3K(SPA3K)和抑制物组织基质金属蛋白酶抑制剂-3(TIMP-3)。与正常大鼠相比,这3个蛋白的表达水平均随着低温海水浸泡时间的延长明显上调。结论低温海水浸泡后的大鼠血浆蛋白质组相对正常大鼠血浆蛋白质组有改变。研究差异蛋白有助于阐明低温损伤的分子机制,为研究和治疗低体温症提供靶标。  相似文献   
27.
The present study investigated the structural evolution of Portland cement (PC) incorporating supplementary cementitious materials (SCMs) exposed to seawater. The samples were made with replacing Portland cement with 10 mass-% silica fume, metakaolin or glass powder. The reaction degree of SCMs estimated by the portlandite consumption shows that metakaolin has the highest reaction degree, thus metakaolin-blended PC exhibits the highest strength. The control exposed to seawater exhibited 14.82% and 12.14% higher compressive strengths compared to those cured in tap water at 7 and 28 days. The samples incorporating metakaolin showed the highest compressive strength of 76.60 MPa at 90 days tap water curing and this was 17% higher than that of the control. Exposure to seawater is found to retard the rate of hydration in all SCM-incorporating systems, while the strength development of the neat PC system is enhanced. The main reaction product that forms during exposure to seawater is Cl-AFm and brucite, while it is predicted by the thermodynamic modelling that a significant amount of M-S-H, calcite and hydrotalcite is to form at an extended period of exposure time.  相似文献   
28.
目的:探讨腔镜器械两种灭菌方法的应用效果。方法选取本院2011年10月~2013年10月使用的腔镜器械384件,随机分为试验组和对照组,192件腔镜器械使用2%碱性戊二醛浸泡消毒灭菌(对照组),192件腔镜器械使用过氧化氢等离子低温灭菌(试验组),比较两组的细菌培养合格情况、消毒灭菌有效性、器械损伤情况、操作人员不良反应情况。结果试验组腔镜器械的细菌培养合格率明显高于对照组,消毒时间明显小于对照组,灭菌后有效时间明显长于对照组,器械损伤率、操作人员的不良反应发生率均明显低于对照组,差异均有统计学意义(P<0.05)。结论2%碱性戊二醛浸泡消毒灭菌、过氧化氢等离子低温灭菌均是腔镜器械的有效灭菌方法。过氧化氢等离子低温灭菌的效果更好,值得临床推广。  相似文献   
29.
Background: To investigate the differences between water immersion (WI) and air insufflation (AI) for colonoscopy under various bowel preparation conditions. Methods: In this study, 526 outpatients were randomly assigned to two groups, namely a WI group (n = 263) and an AI group (n = 263). During the procedure, the quality of bowel preparation, abdominal pain score, cecal intubation rate (CIR), adenoma detection rate (ADR), the intubation times, and other indicators were recorded. After reaching the cecum, each group of patients was subdivided into one of four grades (excellent, good, fair, and poor) according to the quality of bowel preparation.Results: Under various bowel preparation conditions, the pain scores of the AI group were higher than those of the WI group (P < .05), but there was no significant difference between the two groups in CIR (P > .05). For the WI group compared with the AI group, the cecal intubation time (CIT) was prolonged under good bowel preparation (P = .045) and fair bowel preparation (P < .001). No significant differences were observed between the two groups on ADR in all patients (P = .476).Conclusion: Compared with AI colonoscopy, WI colonoscopy can decrease colonoscopy-related pain in patients for unsedated colonoscopy under various bowel preparation conditions, but there is no significant difference in CIR. WI colonoscopy requires longer CIT in patients with good and fair bowel preparation conditions. WI colonoscopy does not significantly increase ADR.  相似文献   
30.
目的:了解海水淹溺肺水肿(PESWD)的病理生理变化与cfos基因表达水平之间的关系。方法:向兔肺内灌入海水,诱发PESWD,用原位杂交和免疫组化方法测定肺组织中cfosmRNA及Fos蛋白的含量。结果:PESWD兔肺上皮组织中cfosmRNA〔(325.46±145.18)〕μm2及Fos蛋白〔(123.93±26.87)μm2〕的含量均显著高于对照组〔分别为(155.93±40.21)μm2和(59.76±24.50)μm2〕。表明在PESWD时cfos基因转录及翻译水平表达均高于对照组。结论:海水淹溺可引起cfos基因表达水平增强,并进一步导致PESWD的其他变化。  相似文献   
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