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1.
陈家亮  夏宇希  曹威  陈凯  王召军 《生物磁学》2014,(8):1500-1502,1506
目的:探讨微伏T波电交替增高与STEMI患者PCI术后室性心律失常的发生关系。方法:选择我院2011年4月-2013年4月收治的68例STEMI患者,所有患者均成功进行了直接PCI,且阻塞远端血流均达到TIMI3级。所有患者于手术后进行了24小时动态心电图检查,并测定微伏T波电交替值。结果:36例发生NSVT患者较未发生32例患者最大微伏T波电交替明显升高,(68.1±6.4VS31.9±3.8μV,P〈0.05)。最大T波电交替值大于45μV预测非持续性室速发生的敏感性为75%,特异性为72%;阳性预测值为70%。阴性预测值77%(AUC=0.84)。经过进一步比较分析发现,ST段抬高的程度与非持续室速的发生无关(AUC=0.61)。结论:微伏T波电交替可预测STEMI患者PCI术后室性心律失常的发生。  相似文献   

2.
目的:探讨ST段抬高型心肌梗死(STEMI)患者与冠状动脉造影阴性的对照组血钾水平以及低血钾发病率的差异;探讨STEMI患者中原发性恶性室性心律失常组和非原发性恶性室性心律失常组血钾水平的差异.方法:选取2007年1月至2009年11月间STEMI并行直接经皮冠状动脉介入术(直接PCI)患者371例,其中男303例,女68例,平均年龄(56.1±11.7)岁.同时选取冠状动脉造影阴性患者(对照组)161例,其中男性131人,女性30人,平均年龄(56.8±10.3)岁.两组基线资料无显著性差异.将血钾含量<3.5mmol/l定义为低血钾,比较2组间血钾含量及低血钾发病率.根据直接PCI之前是否发生原发性室颤和持续性室速,将STEMI患者分为原发性恶性室性心律失常组和非原发性恶性室性心律失常组,本组数据所指原发性恶性室性心律失常仅包括直接PCI之前发生的原发性室颤和持续性室速,其中原发性室颤24例,持续性室速11例.比较2组间血钾水平.结果:血钾含量STEMI患者(3.81±0.49)低于对照者(4.03+0.41)mmol/L,差异有统计学意义(t=5.08,P<0.001).低血钾发病率STEMI(22.6%)高于对照者(6.83%),差异有统计学意义(X2=19.13,P<0.001).STEMI患者中原发性恶性室性心律失常组和非原发性恶性室性心律失常组的血钾水平差异无统计学意义.结论:STEMI患者急性期存在血钾的下降,我们需要积极纠正低血钾,但低血钾与原发性恶性室性心律失常有无必然联系仍需更深入的研究.  相似文献   

3.
视网膜电图是视网膜对光刺激的综合电反应,是目前眼科临床评价视网膜早期功能障碍具有代表性的电生理指标,它主要由 a、b 两个波组成。本文观察了21只清醒 Beagle 狗眼睛的正常ERG 波形,在暗适应条件下,38只眼 a,b 波的峰时值分别为11.3±1.3毫秒和33.7±1.7毫秒,振幅为74.5±32.5微伏和159.5±48.2微伏。左右眼间未见明显差别。  相似文献   

4.
摘要 目的:探讨Tp-e间期、P波离散度(Pd)对室性心律失常病情的预测价值。方法:2016年6月到2018年6月选择在本院诊治的心绞痛患者110例,所有患者都给予动态心电图检查,记录Tp-e间期、Pd值与室性心律失常发生情况。随访患者的心绞痛复发情况,并判定预测价值。结果:在110例患者中,发生室性心律失常48例(失常组),发生率为43.6 %,其中偶发室早21例、频发室早19例、室早4例、心室颤动3例、室性心动过速1例。失常组的Tp-e间期、Pd值都显著高于非失常组(P<0.05)。随访至今,失常组的心绞痛复发率为45.8 %,显著低于对照组的8.1 %(P<0.05)。在失常组中,单因素与多因素logistics回归分析显示Tp-e间期、Pd都为影响患者心绞痛复发的重要因素(P<0.05)。ROC曲线分析显示Tp-e间期、Pd预测心绞痛复发的敏感性与特异性都在85.0 %以上。结论:心绞痛合并室性心律失常患者多伴随有Tp-e间期、Pd增加,也会增加患者的复发率,Tp-e间期、Pd对预测室性心律失常复发情况具有重要价值。  相似文献   

5.
摘要 目的:探讨血清同型半胱氨酸(Hcy)水平与急性ST段抬高型心肌梗死(STEMI)患者经皮冠状动脉介入(PCI)术后左心室重构、心肌灌注以及预后的关系。方法:选择2018年2月至2020年1月我院收治的70例STEMI患者,根据入院时血清Hcy水平分为高水平Hcy组(Hcy>30 μmol/L,41例)和低水平Hcy组(15≤Hcy≤30 μmol/L,29例)。PCI术后1个月、6个月、12个月检测左室重量指数(LVMI)和左心室射血分数(LVEF),复查冠脉造影,评价TIMI心肌灌注分级(TMPG)。Pearson相关或Spearman秩相关性分析Hcy水平与LVMI、LVEF、TMPG分级相关性。所有患者PCI术后随访12个月,记录患者随访期间全因死亡和主要不良心脏事件(MACE)发生情况。Cox风险比例回归分析PCI术后STEMI患者预后的影响因素。结果:高水平Hcy组PCI术后6、12个月 LVEF低于低水平Hcy组(P<0.05),LVMI高于低水平Hcy组(P<0.05),高水平Hcy组PCI术后心肌灌注不良发生率高于低水平Hcy组(P<0.05)。Hcy水平与PCI术后6、12个月 LVEF呈负相关(P<0.05),与LVMI呈正相关(P<0.05),与PCI术后TMPG分级呈负相关(P<0.05)。高水平Hcy组随访期间全因死亡和MACE发生率均高于低水平Hcy组(P<0.05)。Cox风险比例回归分析结果显示Hcy、术前Gensini评分是STEMI患者PCI术后预后不良的影响因素(P<0.05)。结论:高水平Hcy与STEMI患者PCI术后左心室重构、心肌灌注有关,且Hcy是STEMI患者PCI术后发生全因死亡和MACE的影响因素。  相似文献   

6.
IABP在瓣膜病合并巨大左心室患者中的临床应用   总被引:1,自引:0,他引:1  
目的评价瓣膜病合并巨大左心室患者术后应用主动脉内球囊反搏泵(IABP)的效果.方法回顾分析本院1997~2000年瓣膜病合并巨大左心室换瓣术后应用IABP患者26例(组Ⅰ),对照组(组Ⅱ)为同期未应用IABP患者30例.观察其血流动力学、心功能、心律、ST段的,比较两组早期生存率.结果IABP辅助时间为(57±29)h,患者在应用IABP后,桡动脉压力在早期有所下降(P<0.01);舒张压上升(P<0.01);平均动脉压于应用后即可见明显提高,外周阻力明显降低.心律失常的变化于应用IABP后1 h频发室早或室速转为偶发室早,ST段的抬高或降低在30 min~1 h后恢复正常.组Ⅱ患者出现的频发室早或室速于(22±11)h后转为偶发室早,ST段的抬高或降低于(24±10)h后.持续左心功能(CCO)监测结果见组Ⅰ CO、CI于应用IABP后2 h明显恢复,24 h已经恢复到术前水平;组Ⅱ于24 h才有所恢复.组Ⅰ早期生存率为80.3%,与组Ⅱ(64.7%)比较P<0.01.结论IABP能够有效地控制瓣膜病合并巨大左心室患者术后室性心律失常的发生,使心功能得到了有效的支持,大大降低了早期死亡率.  相似文献   

7.
摘要 目的:探讨右室Tei指数、血清醛固酮水平对慢性阻塞性肺病(COPD)患者发生房颤的预测价值。方法:根据房颤的发生情况,将200例COPD患者分为房颤发生组和无房颤发生组。比较两组的病程、COPD严重程度、血清醛固酮(ALD)水平及右室Tei指数、肺动脉压、右心室横径的差异,分析右室Tei指数和ALD预测房颤发生的ROC曲线下面积、截断值、灵敏度及特异度。结果:房颤发生组病程(8.48±1.3和7.59±1.75)、右心室横径(40.52±2.74和36.27±2.4)、血清ALD(137.64±42.77和98.61±15.39)、右室Tei指数(0.37±0.12和0.31±0.07)、COPD、肺动脉高压的严重程度与无房颤发生组比较差异都有统计学意义(P<0.05)。logistic回归分析结果显示ALD、右室Tei指数、病程、和肺动脉高压程度为影响COPD患者发生房颤的独立影响因素。右室Tei指数预测房颤发生的ROC曲线下面积AUC=0.645,截断值为0.420,灵敏度为38.0%,特异度达到93.33%;ALD预测房颤发生的ROC曲线下面积为0.792,截断值为122.72 pg/mL,灵敏度为66.0%,特异度可达到98.0%。结论:右室Tei指数和血清醛固酮水平可作为慢性阻塞性肺病患者发生房颤的预测参考指标。  相似文献   

8.
摘要 目的:开发机器学习模型,并评估其在膝关节周围原发性骨肿瘤诊断方面的准确性。方法:本文将深度卷积神经网络(DCNN)这一深度学习方法应用于膝关节X线图像的影像组学分析,探讨其辅助诊断膝关节周围原发性骨肿瘤的临床价值。结果:该深度学习模型在区分正常与肿瘤影像方面展现出优异的诊断准确性,使用DCNN模型进行5轮测试的总体准确性为(99.8±0.4)%,而阳性预测值和阴性预测值分别为(100.0±0.0)%和(99.6±0.8)%,各个数据集的曲线下面积(AUC)分别为0.99、1.00、1.00、1.0和1.0,平均AUC为(0.998±0.004);进一步使用DCNN模型进行了10轮测试显示其在区分良性与恶性骨肿瘤方面的总体准确性为(71.2±1.6)%,且达到了强阳性预测值(91.9±8.5)%,各个数据集的AUC分别为0.63、0.63、0.58、0.69、0.55、0.63、0.54、0.57、0.73、0.63,平均AUC为(0.62±0.06)。结论:本文是首个将人工智能技术应用于骨肿瘤诊断的X线图像影像组学分析方面的研究,人工智能影像组学模型能够帮助医生自动地快速筛查骨肿瘤,确定良性或恶性肿瘤时,阳性预测值较高。  相似文献   

9.
目的:探讨血清Irisin 水平对急性心肌梗死(AMI)患者PCI术后无复流的预测价值。方法:连续收集西京医院心内科因AMI 行急诊PCI治疗的169 例患者的临床及冠脉影像学资料。根据TIMI血流分级,将病人分为两组,正常血流组和无复流组;采用酶 联免疫吸附试验(ELISA)检测患者血清中Irisin 水平,根据Irisin 水平分为低Irisin 组和高Irisin 组,分析Irisin 与无复流发生的关 系。结果:①169例患者发生无复流40 例,无复流发生率为23.6%(40/169);②无复流组与正常血流组相比,血清Irisin 水平显著降 低(4766± 1725 ng/mLvs 8125± 2904 ng/mL,P<0.05);③急性心梗发生后,血浆Irisin 水平逐渐升高,3 小时内组Irisin 水平显著低 于24 小时后组(4050± 1739 ng/mL vs8358± 3042 ng/mL,P<0.05),且3 小时内组无复流显著高于24 小时后组(71.42%vs 12.9%, P<0.05);④低Irisin 组中无复流的发生率显著高于高Irisin 组(58.1% vs 11.9%,P<0.05);⑤多元Logistic 回归显示Irisin 是急诊 PCI术后无复流发生的保护因素(OR:0.861,95%CI:0.793-0.909,P<0.05)。结论:低水平的血清Irisin 能有效预测急性心肌梗死患者 PCI术后无复流的发生,且Irisin 能明显改善PCI术后无复流。  相似文献   

10.
摘要 目的: 探讨产后抑郁症患者感觉门控 P50 的变化特征,为产后抑郁患者的早期预防提供参考依据。方法: 采用配对听觉条件 (S1)、测试(S2)刺激范式, 对本院 2011 年 1 月至 2012 年 6 月收治的 26 例产后抑郁症患者(实验组)进行听觉诱发电位 P50 检测, 测量 P50 的潜伏期、 波幅, 并与 25 例健康被试者(对照组)的结果进行比较。 结果: (1) 与对照组相比, 实验组 S1-P50 潜伏期[(56.62 ± 17.42) ms vs. (49.86 ± 15.21) ms], S2-P50 潜伏期[(57.36 ± 15.42) ms vs. (50.04 ± 16.27) ms]的差异均无统计学意义(P>0.05); (2) 与对照组相比, 实验组 S1-P50 波幅[(3.58 ± 1.72) μV vs. (1.13 ± 0.91) μV]显著降低, 差异有统计学意义(P<0.05); S2-P50 波幅[ (1.32 ± 1.16) μV vs. (1.48 ± 1.05) μV]差异无统计学意义(P>0.05); (3) 与对照组相比, 实验组 S2/S1 波幅比值[(1.17 ± 0.26) vs. (0.41 ± 0.13)]显著升高, 差异有统计学意义(P<0.05)。结论: 产后抑郁症患者感觉门控抑制能力有缺陷, P50 受损指标可能为评估 产后抑郁症患者的潜在生物学指标。  相似文献   

11.
Defects in mitochondrial energy metabolism have been implicated in the pathology of several neurodegenerative disorders. In addition, the reactive metabolites generated from the metabolism and oxidation of the neurotransmitter dopamine (DA) are thought to contribute to the damage to neurons of the basal ganglia. We have previously demonstrated that infusions of the metabolic inhibitor malonate into the striata of mice or rats produce degeneration of DA nerve terminals. In the present studies, we demonstrate that an intrastriatal infusion of malonate induces a substantial increase in DA efflux in awake, behaving mice as measured by in vivo microdialysis. Furthermore, pretreatment of mice with tetrabenazine (TBZ) or the TBZ analogue Ro 4-1284 (Ro-4), compounds that reversibly inhibit the vesicular storage of DA, attenuates the malonate-induced DA efflux as well as the damage to DA nerve terminals. Consistent with these findings, the damage to both DA and GABA neurons in mesencephalic cultures by malonate exposure was attenuated by pretreatment with TBZ or Ro-4. Treatment with these compounds did not affect the formation of free radicals or the inhibition of oxidative phosphorylation resulting from malonate exposure alone. Our data suggest that DA plays an important role in the neurotoxicity produced by malonate. These findings provide direct evidence that inhibition of succinate dehydrogenase causes an increase in extracellular DA levels and indicate that bioenergetic defects may contribute to the pathogenesis of chronic neurodegenerative diseases through a mechanism involving DA.  相似文献   

12.
2018年中国植物科学若干领域重要研究进展   总被引:1,自引:0,他引:1  
2018年中国植物科学继续呈现快速发展的态势, 我国科学家在国际植物科学主流学术刊物发表论文数量大幅增加, 取得了多项具有重要影响的成果。调控植物生长-代谢平衡实现可持续农业发展入选2018年度中国科学十大进展; 中国被子植物区系进化历史研究入选2018年度中国生命科学十大进展。以水稻为代表的农作物和果蔬等经济作物研究在国际上已呈现出明显的优势, 若干领域已从“追赶”状态跨越到“领跑”地位。该文对2018年中国科学家在植物科学若干领域取得的重要研究成果进行了概括性评述, 旨在全面追踪和报道当前中国植物科学领域的发展前沿和热点, 展示中国科学家所取得的杰出成就。  相似文献   

13.
2017年中国植物科学若干领域重要研究进展   总被引:1,自引:0,他引:1  
2017年中国植物科学继续保持高速发展态势, 重大成果频出, 具体表现在中国植物学家在国际顶级学术期刊发表的文章数量平稳上升。中国植物科学领域的研究工作者成果精彩纷呈, 如新型广谱抗病机制的发现、水稻广谱抗病遗传基础及机制和疫霉菌诱发病害成灾机制研究等。2017年中国生命科学领域十大进展评选中, 有两项植物科学领域的研究成果入选。水稻生物学、进化与基因组学和激素生物学等领域学科发展突出。另外, 值得一提的是, 长期从事高等植物与代谢途径调控分子网络研究和水稻品种设计育种的李家洋院士的研究成果“水稻高产优质性状形成的分子机理及品种设计”荣获2017年国家自然科学一等奖。这一具有重大国际影响的开创性贡献标志着中国植物科学在该领域的国际科学前沿居于引领和卓越地位。该文对2017年中国本土科学家在植物科学若干领域取得的重要研究成果进行了系统梳理, 旨在全面追踪和报道当前中国植物科学领域发展的最新前沿动态, 与广大读者共同分享我国科学家所取得的辉煌成就。  相似文献   

14.
葫芦科植物包括多种瓜类蔬菜,对其进行离体培养研究具有重要的理论和实践意义。综述了国内在葫芦科植物器官培养、体细胞胚胎发生、花药培养、原生质体培养和体细胞杂交及离体遗传转化等方面取得的研究进展,并对葫芦科植物离体培养、遗传转化与育种的前景作了展望。  相似文献   

15.
Somatostatin (SST) peptide is a potent inhibitor of insulin secretion and its effect is mediated via somatostatin receptor 5 (SSTR5) in the endocrine pancreas. To investigate the consequences of gene ablation of SSTR5 in the mouse pancreas, we have generated a mouse model in which the SSTR5 gene was specifically knocked down in the pancreatic beta cells (betaSSTR5Kd) using the Cre-lox system. Immunohistochemistry analysis showed that SSTR5 gene expression was absent in beta cells at three months of age. At the time of gene ablation, betaSSTR5Kd mice demonstrated glucose intolerance with lack of insulin response and significantly reduced serum insulin levels. Insulin tolerance test demonstrated a significant increase of insulin clearance in vivo at the same age. In vitro studies demonstrated an absence of response to SST-28 stimulation in the betaSSTR5Kd mouse islet, which was associated with a significantly reduced SST expression level in betaSSTR5Kd mice pancreata. In addition, betaSSTR5Kd mice had significantly reduced serum glucose levels and increased serum insulin levels at 12 months of age. Glucose tolerance test at an older age also indicated a persistently higher insulin level in betaSSTR5Kd mice. Further studies of betaSSTR5Kd mice had revealed elevated serum C-peptide levels at both 3 and 12 months of age, suggesting that these mice are capable of producing and releasing insulin to the periphery. These results support the hypothesis that SSTR5 plays a pivotal role in the regulation of insulin secretion in the mouse pancreas.  相似文献   

16.
2018年中国植物科学继续呈现快速发展的态势, 我国科学家在国际植物科学主流学术刊物发表论文数量大幅增加, 取得了多项具有重要影响的成果。调控植物生长-代谢平衡实现可持续农业发展入选2018年度中国科学十大进展; 中国被子植物区系进化历史研究入选2018年度中国生命科学十大进展。以水稻为代表的农作物和果蔬等经济作物研究在国际上已呈现出明显的优势, 若干领域已从“追赶”状态跨越到“领跑”地位。该文对2018年中国科学家在植物科学若干领域取得的重要研究成果进行了概括性评述, 旨在全面追踪和报道当前中国植物科学领域的发展前沿和热点, 展示中国科学家所取得的杰出成就。  相似文献   

17.
我国葫芦科植物离体培养研究进展   总被引:5,自引:0,他引:5  
葫芦科植物包括多种瓜类蔬菜,对其进行离体培养研究具有重要的理论和实践意义.综述了国内在葫芦科植物器官培养、体细胞胚胎发生、花药培养、原生质体培养和体细胞杂交及离体遗传转化等方面取得的研究进展,并对葫芦科植物离体培养、遗传转化与育种的前景作了展望.  相似文献   

18.
Abstract. Changes are described in aquatic vegetation in oligotrophic, groundwater-fed Rhine floodplain streams in Alsace (eastern France), resulting from disturbance. Disturbance factors include changes in nutrients, either permanent ones - effluent from a waste water treatment plant or trout hatcheries - or periodic ones: flooding. Regular inputs of high levels of phosphate and ammonia modified the macrophyte vegetation in these streams. The floristic composition, which was characteristic of oligotrophic waters upstream of the eutrophicated sector, changed to that of a eutrophic situation as originally found downstream. Periodic disturbance by floods which normally occur once a year, irregularly eutrophicates the small streams, causing the development of a mixture of eutrophic and oligotrophic species. Six macrophyte communities are distinguished, indicating different trophic levels. The aquatic vegetation is adapted to the variations of phosphate and ammonia levels. Hence, aquatic macrophytes can be used as bio-indicators of fluctuations in water nutrient levels in relation to the type of disturbance.  相似文献   

19.
We report the appearance of apoptotic cells in experimental myocardial infarction (rabbit heart) in in situ and in vitro preparations. Apoptosis was recognized by intravital staining with Hoechst 33342 (Ho342), by nick-end labeling (TUNEL) and by DNA laddering. A steady rise in the relative number of apoptotic cardiomyocytes (apoptotic index) was noted in in situ preparations. Apoptosis was first noted 6 h after the onset of ischemia with its highest value occurring after 72 h. Apoptotic nuclei were absent in remote areas of the left and right ventricles. Apoptotic nuclei within the infarcted area showed diminished intensity of Ho342 fluorescence. Three days after ischemia, a border zone adjacent to the infarcted area consisting of apoptotic macrophages was recognized. A novel finding was the appearance of apoptotic cardiomyocytes in the isolated perfused ischemic heart. Occurring as early as 50 min after the onset of ischemia, a high apoptotic index was present adjacent to the ligature placed around the coronary artery. This observation provides the opportunity to selectively examine factors leading to apoptosis in the ischemic heart under controlled experimental conditions.  相似文献   

20.
The detailed mechanisms underlying morphine-signaling pathways in platelets remain obscure. Therefore, we systematically examined the influence of morphine on washed human platelets. In this study, washed human platelet suspensions were used for in vitro studies. Furthermore, platelet thrombus formation induced by irradiation of mesenteric venules with filtered light in mice pretreated with fluorescein sodium was used for an in vivo thrombotic study. Morphine concentration dependently (0.6, 1, and 5 microM) potentiated platelet aggregation and the ATP release reaction stimulated by agonists (i.e., collagen and U46619) in washed human platelets. Yohimbine (0.1 microM), a specific alpha(2)-adrenoceptor antagonist, markedly abolished the potentiation of morphine in platelet aggregation stimulated by agonists. Morphine also potentiated phosphoinositide breakdown and intracellular Ca(2+) mobilization in human platelets stimulated by collagen (1 microg/ml). Moreover, morphine (0.6-5 microM) markedly inhibited prostaglandin E(1) (10 microM)-induced cyclic AMP formation in human platelets, while yohimbine (0.1 microM) significantly reversed the inhibition of cyclic AMP by morphine (0.6 and 1 microM) in this study. The thrombin-evoked increase in pH(i) was markedly potentiated in the presence of morphine (1 and 5 microM). Morphine (2 and 5 mg/g) significantly shortened the time require to induce platelet plug formation in mesenteric venules. We concluded that morphine may exert its potentiation in platelet aggregation by binding to alpha(2)-adrenoceptors in human platelets, with a resulting inhibition of adenylate cyclase, thereby reducing intracellular cyclic AMP formation followed by increased activation of phospholipase C and the Na(+)/H(+) exchanger. This leads to increased intracellular Ca(2+) mobilization, and finally potentiation of platelet aggregation and of the ATP release reaction.  相似文献   

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