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291.
Chronic alcohol consumption leads to myocardial injury, ventricle dilation, and cardiac dysfunction, which is defined as alcoholic cardiomyopathy (ACM). To explore the induced myocardial injury and underlying mechanism of ACM, the Liber-DeCarli liquid diet was used to establish an animal model of ACM and histopathology, echocardiography, molecular biology, and metabolomics were employed. Hematoxylin-eosin and Masson’s trichrome staining revealed disordered myocardial structure and local fibrosis in the ACM group. Echocardiography revealed thinning wall and dilation of the left ventricle and decreased cardiac function in the ACM group, with increased serum levels of brain natriuretic peptide (BNP) and expression of myocardial BNP mRNA measured through enzyme-linked immunosorbent assay and real-time quantitative polymerase chain reaction (PCR), respectively. Through metabolomic analysis of myocardium specimens, 297 differentially expressed metabolites were identified which were involved in KEGG pathways related to the biosynthesis of unsaturated fatty acids, vitamin digestion and absorption, oxidative phosphorylation, pentose phosphate, and purine and pyrimidine metabolism. The present study demonstrated chronic alcohol consumption caused disordered cardiomyocyte structure, thinning and dilation of the left ventricle, and decreased cardiac function. Metabolomic analysis of myocardium specimens and KEGG enrichment analysis further demonstrated that several differentially expressed metabolites and pathways were involved in the ACM group, which suggests potential causes of myocardial injury due to chronic alcohol exposure and provides insight for further research elucidating the underlying mechanisms of ACM.  相似文献   
292.
目的探讨红花对兔肠缺血再灌注损伤(IRI)时微循环的改善作用.方法将30只日本大耳兔随机分为假手术组(S组)、缺血再灌注组(IR组)和缺血再灌注+红花注射液组(SI组).制作在体兔IRI模型.观察和记录各组动物肠系膜微循环变化,包括微动脉管径(AD)、微静脉管径(VD)、微动脉流速(AFV)、微静脉流速(VFV)和白细胞黏附数,电镜下观察肠黏膜超微结构改变.结果 IR组肠系膜微动、静脉管径缩小,血流速度减慢,多数肠黏膜微结构破坏严重.SI组微动、静脉管径及血流速度明显改善,肠黏膜超微结构异常改变不同程度减轻.结论在兔肠IRI发生后使用红花注射液能有效改善肠系膜的微循环,从而对肠黏膜起到良好的保护作用.  相似文献   
293.
Urine proteomic applications in children suggested their potential in discriminating between healthy subjects from those with respiratory diseases. The aim of the current study was to combine protein fractionation, by urinary extracellular vesicle isolation, and proteomics analysis in order to establish whether different patterns of respiratory impedance in healthy preschoolers can be characterized from a protein fingerprint. Twenty-one 3–5-yr-old healthy children, representative of 66 recruited subjects, were selected: 12 late preterm (LP) and 9 full-term (T) born. Children underwent measurement of respiratory impedance through Forced Oscillation Technique (FOT) and no significant differences between LP and T were found. Unbiased clustering, based on proteomic signatures, stratified three groups of children (A, B, C) with significantly different patterns of respiratory impedance, which was slightly worse in group A than in groups B and C. Six proteins (Tripeptidyl peptidase I (TPP1), Cubilin (CUBN), SerpinA4, SerpinF1, Thy-1 membrane glycoprotein (THY1) and Angiopoietin-related protein 2 (ANGPTL2)) were identified in order to type the membership of subjects to the three groups. The differential levels of the six proteins in groups A, B and C suggest that proteomic-based profiles of urinary fractionated exosomes could represent a link between respiratory impedance and underlying biological profiles in healthy preschool children.  相似文献   
294.
Based on the cellular automata method (CA model) and the mobile lattice gas model (MLG model), we have developed a heterogeneous lattice gas model for simulating pedestrian evacuation processes in an emergency. A local population density concept is introduced first. The update rule in the new model depends on the local population density and the exit crowded degree factor. The drift D, which is one of the key parameters influencing the evacuation process, is allowed to change according to the local population density of the pedestrians. Interactions including attraction, repulsion, and friction between every two pedestrians and those between a pedestrian and the building wall are described by a nonlinear function of the corresponding distance, and the repulsion forces increase sharply as the distances get small. A critical force of injury is introduced into the model, and its effects on the evacuation process are investigated. The model proposed has heterogeneous features as compared to the MLG model or the basic CA model. Numerical examples show that the model proposed can capture the basic features of pedestrian evacuation, such as clogging and arching phenomena.  相似文献   
295.
郑海燕  梁静芝 《应用数学》2013,35(7):550-552
目的探讨不同程度高钠血症与颅脑损伤患者死亡的相关风险.方法将近5年ICU的颅脑损伤患者431例根据血钠水平分为4组,非高钠组(<150mmol/L)、轻度高钠组(150~155mmol/L)、中度高钠组(155~160 mmol/L)、重度高钠组(≥160mmol/L),分析血钠水平与患者死亡的相关风险.结果重度高钠组患者的Glasgow昏迷评分(GCS)3.27±0.89,APACHE-II评分35.25±6.01,病死率93.82%,与轻、中度高钠组患者相比,具有统计学差异(P<0.05).Logistic多因素分析提示GCS评分下降(OR=3.96,95%CI=1.43~10.96,P<0.05),APACHE-II评分升高(OR=1.32,95%CI=1.21~1.41,P<0.05)和重度高钠血症(OR=6.07,95%CI=3.19~13.87,P<0.05)是颅脑损伤患者的死亡危险因素.结论重度高钠血症是脑外伤患者死亡的主要危险因素之一.  相似文献   
296.
目的探讨膝关节镜下手术修复和术后药物辅助治疗半月板损伤的疗效。方法对22例半月板撕裂的患者行膝关节镜下半月板修复术(其中16例从外到内缝合,6例从内到外缝合),术后给予玻璃酸钠膝关节腔内注射辅助治疗,通过二期膝关节镜和MRI检查、Lysholm膝关节功能评分对治疗效果进行评价。结果22例患者膝关节镜下半月板修复术均取得成功。二期关节镜检查5例,显示半月板愈合良好;MRI复查17例,显示半月板愈合15例,未完全愈合和未愈合各1例;术后Lysholm平均评分较术前明显提高,差异具有统计学意义(P<0.01);疗效优14例,良6例,可1例,差1例,优良率90.9%(20/22)。结论膝关节镜下半月板修复术结合玻璃酸钠膝关节腔内注射治疗半月板损伤可取得良好的疗效。  相似文献   
297.
Celastrol, a pentacyclic triterpene isolated from the traditional Chinese medicine Tripterygium wilfordii Hook. F., exhibits effectiveness in protection against multiple central nervous system (CNS) diseases such as cerebral ischemia, but its influence on lipidomics still remains unclear. Therefore, in the present study, the efficacy and potential mechanism of celastrol against cerebral ischemia/reperfusion (I/R) injury were investigated based on lipidomics. Middle cerebral artery occlusion (MCAO) followed by reperfusion was operated in mice to set up a cerebral I/R model. TTC staining and TUNEL staining were used to evaluate the therapeutic effect of celastrol. Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC/MS) was employed for lipidomics analysis in ipsilateral hemisphere and plasma. Celastrol remarkably reduced cerebral infarct volume and apoptosis positive cells in tMCAO mice. Furthermore, lipidomics analysis showed that 14 common differentially expressed lipids (DELs) were identified in brain and five common DELs were identified in plasma between the Sham, tMCAO and Celastrol-treated tMCAO groups. Through enrichment analysis, sphingolipid metabolism and glycerophospholipid metabolism were demonstrated to be significantly enriched in all the comparison groups. Among the DELs, celastrol could reverse cerebral I/R injury-induced alteration of phosphatidylcholine, phosphatidylethanolamine and sulfatide, which may be responsible for the neuroprotective effect of celastrol. Our findings suggested the neuroprotection of celastrol on cerebral I/R injury may be partially associated with its regulation of lipid metabolism.  相似文献   
298.
为了解沈阳市0~7岁儿童全血铜、锌、钙、镁、铁元素缺乏情况,探讨性别、年龄与5种元素含量之间的关系,对沈阳市20335名0~7岁儿童进行末梢指间采血,用BH5100型原子吸收光谱仪测定了全血中钙、镁、铜、铁、锌的含量。结果表明,儿童血锌平均水平低于正常值范围,缺乏最严重,缺乏率为77.78%;血铜、锌、铁缺乏率与年龄有线性相关关系,且随着年龄的增加呈现下降趋势(P〈0.05),下降速度在40%~60%之间;全血中5种元素均存在年龄差异(P〈0.01),血铜元素男童明显高于女童(P〈0.01)。提示儿童应加强膳食干预,提高各种富含微量元素的食物摄人,以促进儿童的生长发育。  相似文献   
299.
为了解甘肃省裕固族地区儿童智商发育及血清钙、镁、铁、锌、铜水平,收集可能影响儿童智力发育的资料,给相关研究提供科学依据,采用整群随机抽样的方法,抽取甘肃省张掖市肃南裕固族自治县的部分7~13岁儿童作为研究对象,自行设计问卷收集儿童信息、现场采用瑞文智力测试图谱对研究对象进行了智力测试,同时采集部分儿童指端末梢血,用原子吸收光谱仪测定了血钙、镁、铁、锌、铜水平,并做了相关性分析。结果表明,智商均值为(106.26±14.10)分,接近人群中等水平(90~109分);按年龄、民族和城乡出生地分组,13~14岁组与其他各年龄组间均存在统计学差异,7~9、10~12岁组内未发现统计学差异,组间存在部分统计学差异;非裕固族、城市儿童智商值高于裕固族、农村儿童,差异有统计学意义。全血5种元素测定结果:钙、镁、铁、锌、铜元素平均水平分别为:(2.02±0.58)mmol/L、(1.69±0.39)mmol/L、(8.67±2.01)mmol/L、(91.51±29.23)μmol/L、(17.05±6.13)μmol/L,均处于人群正常水平;各年龄组间比较,钙、锌、镁显示出统计学差异,其他元素及组间对比,均无统计学意义;按农村与城镇、裕固族与非裕固族分类,钙、镁、铁、锌、铜元素水平均未发现统计学差异;进一步按照智力等级进行相关性分析,显示锌的差别有统计学意义。提示与全国儿童智力发育水平相比,裕固族地区儿童IQ及血清钙、镁、铁、锌、铜元素平均水平接近人群正常水平,但智力与锌摄入水平存在统计学相关;城乡等社会因素与裕固族地区儿童智力相关性更大。  相似文献   
300.
为探讨儿童低水平铅暴露对其GH/IGF1轴的影响,用原子吸收光谱法检测了121例0.5~16岁儿童全血铅水平(BPL),化学发光法测定了生长激素(GH)水平,酶联免疫吸附法测定了胰岛素样生长因子-1(IGF-1)和胰岛素样生长因子结合蛋白-3(IGFBP-3);按血铅水平分成两组:A组69例,B组52例,年龄最小0.5岁,最大16岁,中位数4岁。ρ(BPL)50μg/L为A组,ρ(BPL)≥50μg/L为B组,应用独立样本t检验比较了两组IGF-1、IGFBP3和GH水平的差异。结果表明,总体血铅水平为8~146μg/L,总体中位数47μg/L;A组血IGFBP3水平明显高于B组,其差异有极显著意义;A组IGF-1水平高于B组,但无统计学意义。提示低水平铅暴露可能对GH/IGF1轴产生影响,从而影响儿童体格发育。  相似文献   
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