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101.
To elucidate whether the accumulation of elements occurred simultaneously in the various arteries with aging, the authors investigated age-related changes of elements in the eight arteries, such as the thoracic and abdominal aortas and the coronary, common carotid, pulmonary, splenic, common iliac, and uterine arteries, and the relationships in the element contents among their arteries. After ordinary dissection by medical students was finished, the thoracic and abdominal aortas and the coronary, common carotid, pulmonary, splenic, common iliac, and uterine arteries were resected from the subjects, who ranged in age from 58 to 94 yr. The element contents were analyzed by inductively coupled plasma-atomic emission spectrometry. It was found that the accumulation of Ca was the highest in the common iliac artery and decreased in the order of the uterine artery, abdominal aorta, coronary artery, thoracic aorta, splenic artery, common carotid artery, and pulmonary artery. Regarding the relationships in the element contents among the eight arteries, it was found that there were significant direct correlations in the contents of Ca, P, Mg, Zn, Fe, and Na between the coronary and splenic arteries, and there were significant correlations in the contents of Ca, P, and Mg between the abdominal aorta and pulmonary artery.  相似文献   
102.
We sought to delineate mechanisms through which the lack of plasminogen activator inhibitor (PAI)-1 in the heart affects remodeling of the heart early after myocardial infarction (MI). MI was induced by coronary occlusion in 10-weeks old PAI-1 knockout (KO) and control mice. Three days after MI, systolic and diastolic function was assessed with high-resolution echocardiography, infarct size was determined biochemically and histologically and accumulation of acute inflammatory cells in zones of infarction was characterized by immunocytochemistry. PAI-1 KO mice exhibited markedly thickened diastolic left ventricular anterior walls (1.38 ± 0.38 mm vs. 0.77 ± 0.13 SD), more profound depression of global and regional cardiac function (19 vs. 22% fractional shortening), and greater evidence of diastolic dysfunction (average E wave amplitude = 568 vs. 675 mm/s) all of which were significant. Markedly greater extent of infarction was demonstrated biochemically and histologically in knockout mice compared with controls (76 vs. 29% of the left ventricle, P < 0.05) associated with striking hemorrhage and intense inflammation. Fibrosis normalized for infarct size was markedly reduced (0.006 vs. 0.022 μg hydroxyproline/mg dry weight). Thus, lack of PAI-1 in the heart exerted deleterious effects mediated, at least in part by increased inflammation and hemorrhage and attenuating of fibrosis.  相似文献   
103.
重度创伤性脑损伤后肠黏膜屏障应激性变化的模型   总被引:1,自引:0,他引:1  
目的建立一种观察重度创伤性脑损伤(TBI)后肠黏膜屏障(IMB)应激性变化的模型。方法选用雄性Wistar大鼠64只,随机分为两组。TBI组(32只):采用改良的Feeney自由落体撞击法,建立TBI模型;假手术对照组(32只):只开骨窗,不行落体致伤。两组大鼠分别按术后6、12、24和48h时相点分为4个亚组(每组均为8只),观察脑组织、肠黏膜组织病理以及扫描和透射电镜下肠黏膜超微结构的变化。结果光镜下TBI组肠黏膜上皮细胞受损,电镜下还可见细胞间紧密连接较对照组明显增宽。结论用改良的Feeney自由落体撞击法,建立的重度TBI大鼠模型肠黏膜上皮细胞受损,细胞间紧密连接增宽,提示其IMB的功能的确发生了应激性损害,说明这种用来观察重度TBI后IMB应激性变化的模型是成功的。  相似文献   
104.
Cardiac rupture and ventricular remodeling are recognized as the severe complications and major risk factors of acute myocardial infarction (AMI). This study aims to evaluate the regulatory roles of interleukin-1 receptor-associated kinase 3 (IRAK3) and nuclear factor-κB (NF-κB) signaling pathway in cardiac rupture and ventricular remodeling. Microarray analysis was performed to screen AMI-related differentially expressed genes and IRAK3 was identified. The models of AMI were established in male C57BL/6 mice to investigate the functional role of IRAK3. Afterwards, lentivirus recombinant plasmid si-IRAK3 was constructed for IRAK3 silencing. Next, cardiac function parameters were measured in response to IRAK3 silencing. The regulatory effects that IRAK3 had on myocardial infarct size and the content of myocardial interstitial collagen were analyzed. The regulation of IRAK3 silencing on the NF-κB signaling pathway was further assayed. The obtained results indicated that highly expressed IRAK3 and activated NF-κB signaling pathway were observed in myocardial tissues of mouse models of AMI, accompanied by increased expression of matrix metalloproteinase (MMP)-2/9 and tissue inhibitor of metalloproteinase 2 (TIMP-2). Notably, IRAK3 gene silencing inhibited the activation of NF-κB signaling pathway. Furthermore, IRAK3 gene silencing led to the decreased thickness of infarct area and collagen content of myocardial interstitium, alleviated diastolic, and systolic dysfunctions, as well as, facilitated cardiac functions in mice with AMI, corresponding to decreased expression of MMP-2/9 expression and increased expression of TIMP-2. Taken together, silencing of IRAK3 inactivates the NF-κB signaling pathway, and thereby impeding the cardiac rupture and ventricular remodeling, which eventually prevents AMI progression.  相似文献   
105.
目的:探讨脾动脉介入栓塞治疗外伤性脾破裂的临床效果及对患者免疫功能的影响。方法:选择2013年4月到2017年2月在中国人民解放军第九七医院进行急诊治疗的116例外伤性脾破裂患者,根据治疗方法的不同将其分为观察组60例与对照组56例,对照组接受脾脏切除手术,观察组给予脾动脉介入栓塞治疗,记录和比较两组的术后下床活动时间、术后住院时间、术后肛门排便时间、术后肛门排气时间、术中输血量、手术时间与治疗前后CD4~+/CD8~+、CD8~+、CD4~+、CD3~+的变化及不良反应的发生情况。结果:所有患者都完成治疗并抢救成功,观察组的术后下床活动时间、术后住院时间、术后肛门排便时间、术后肛门排气时间、术中输血量、手术时间都少于对照组(P0.05)。观察组围手术期间的急性肠梗阻、急性胰腺炎、肺炎等并发症发生率为3.33%,对照组为17.86%,观察组低于对照组(P0.05)。术后14天,两组白细胞与血小板含量均显著高于术前1天(P0.05),而观察组血小板含量显著低于对照组(P0.05),但两组白细胞含量比较差异无统计学意义(P0.05)。观察组术后14天与术后1个月的CD4+/CD8+、CD4+、CD3+值均明显高于对照组(P0.05),两组CD8+对比差异无统计学意义(P0.05)。结论:脾动脉介入栓塞治疗外伤性脾破裂能提高治疗的临床效果,减少术后并发症的发生,促进患者免疫功能的恢复。  相似文献   
106.
目的:检测未足月胎膜早破合并绒毛膜羊膜炎(HCA)孕妇血清淀粉样蛋白A(SAA)、血小板激活因子(PAF)水平,并探讨其临床意义。方法:选择从2013年7月到2017年7月,在我院接受治疗的165例胎膜早破孕产妇作为研究对象。165例患者中,未足月胎膜早破者80例(未足月胎膜早破组),足月胎膜早破者85例(足月胎膜早破组),再根据是否合并HCA分为合并HCA胎膜早破组43例和未合并HCA胎膜早破组122例。另选取同期在我院体检的80例健康孕产妇志愿者作为正常组,对比各组血清SAA和PAF水平,分析合并与未合并HCA胎膜早破组的妊娠结局,利用受试者工作特征(ROC)曲线分析血清SAA和PAF对未足月胎膜早破是否合并HCA的诊断价值。结果:未足月胎膜早破组及足月胎膜早破组的血清SAA和PAF水平均明显高于正常组,且未足月胎膜早破组又高于足月胎膜早破组,差异有统计学意义(P0.05)。未足月胎膜早破组80例患者中HCA发生率为35.00%(28/80),明显高于足月胎膜早破组的17.65%(15/85),差异有统计学意义(P0.05)。合并HCA胎膜早破组的血清SAA和PAF水平均明显高于未合并HCA胎膜早破组,差异有统计学意义(P0.05)。合并HCA的未足月胎膜早破患者血清SAA和PAF水平高于未合并HCA的未足月胎膜早破患者(P0.05)。合并HCA的胎膜早破组的产后大出血、剖宫产以及新生儿肺炎的发生率均明显高于未合并HCA胎膜早破组,差异有统计学意义(P0.05)。根据ROC曲线分析可知,血清SAA和PAF对未足月胎膜早破是否合并HCA的诊断价值较高。结论:血清SAA、PAF水平在未足月胎膜早破合并HCA孕妇中明显升高,二者对此种合并症具有较高的诊断价值。临床诊疗过程中可将SAA及PAF纳入到指标监测体系中,从而为临床治疗提供指导。  相似文献   
107.
Reactive astrocytes are implicated in traumatic spinal cord injury (TSCI). Interestingly, naïve astrocytes can easily transform into neurotoxic reactive astrocytes (A1s) with inflammatory stimulation. Previous studies demonstrated that microRNA(miR)-21a-5p was up-regulated in spinal cord tissue after TSCI; however, it is not clear whether this affected reactive astrocyte polarization. Here, we aim to detect the effects of miR-21a-5p on the induction of A1 formation and the underlying mechanisms. Our study found that the expression of miR-21a-5p was significantly increased while that of Cntfr α was decreased, since naïve astrocytes transformed into A1s 3 days post-TSCI; the binding site between miR-21a-5p and Cntfr α was further confirmed in astrocytes. After treatment with CNTF, the levels of A1 markers decreased while that of A2 increased. The expression of A1 markers significantly decreased with the downregulation of miR-21a-5p, while Cntfr α siRNA treatment caused the opposite both in vitro and in vivo. To summarize, miR-21a-5p/Cntfr α promotes A1 induction and might enhance the inflammatory process of TSCI; furthermore, we identified, for the first time, the effect and potential mechanism by which CNTF inhibits naïve astrocytes transformation into A1s. Collectively, our findings demonstrate that targeting miR-21a-5p represents a prospective therapy for promoting the recovery of TSCI.  相似文献   
108.
109.
110.
目的:探讨胎膜早破对分娩方式与结果的影响,提高对产程观察的重视。方法:统计分析249例孕足月胎膜早破者的分娩方式、产程及母儿并发症,并与249例随机抽取同期孕足月无胎膜早破的产妇进行对照。结果:胎膜早破组自然分娩率明显低于对照组(P<0.05),产褥感染、新生儿窒息发生率明显高于对照组(P<0.05)。结论:胎膜早破易感染,并导致胎儿宫内窘迫和新生儿窒息,与难产、剖宫产有相关性,应合理选择分娩方式,积极处理产程,以确保母婴安全。  相似文献   
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