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71.
本研究探讨超声心动图在胎儿先心病诊断中的价值以及影响先心病发病的危险因素。采用回顾性研究方法,选取孕产妇18987例,均进行系统的彩色多普勒超声检查,同时问卷调查胎儿先心病家庭65例(病例组)及130例正常胎儿家庭(对照组)的病史等情况。结果显示,先心病发病率为0.43%,疾病类型中:以单纯性室间隔缺损、心内膜垫缺损和右心室双出口为主;Logistic回归分析结果显示:产妇年龄、孕期有致畸物接触史、产妇糖尿病、产妇结缔病、不良妊娠史、染色体异常、胎儿早期NT值、先心病家族史是先心病发生的影响因素(P<0.05)。从上述结果可知,超声心动图在胎儿先心病诊断中有较好的价值,先心病发病受产妇年龄、致畸物接触史等因素的影响。  相似文献   
72.
钟小东  陈学清  王晨  娄林娟  冯棋佳 《应用数学》2015,37(11):964-966,970
目的 探讨无创正压通气对慢性阻塞性肺疾病(COPD)合并肺源性心脏病的疗效和对患者血浆C 反应蛋白(CRP)和脑钠素(BNP)水平的影响。方法 将2012 年1 月到2014 年1月收治的120 例COPD 急性加重期合并肺源性心脏病患者随机分为观察组(60 例)和对照组(60 例),对照组给予常规治疗,观察组在此基础上给予无创正压通气治疗。治疗前和治疗3d 后分别进行动脉血气分析,比较患者血pH 值、PaO2、PaCO2和动脉血氧饱和度(SaO2)在治疗前后的改变,并监测治疗前后血浆CRP和BNP 水平的改变。结果 治疗3d 后,两组患者的pH 值、PaO2、SaO2均较治疗前明显升高,PaCO2较治疗前明显降低,而观察组患者治疗后的动态血气分析指标的改善情况明显优于对照组,均有统计学差异(均P<0.05)。两组患者的血浆CRP 和BNP 水平均较治疗前明显降低,而观察组患者治疗后的血浆CRP 和BNP 水平明显低于对照组,均有统计学差异(均P<0.05)。结论 无创正压通气治疗COPD 合并肺源性心脏病,能够有效改善血气指标,提高SaO2和PaO2,同时降低血浆CRP 和BNP 的水平,值得在临床推广应用。  相似文献   
73.
Cardiac fibrosis occurs after pathological stimuli to the cardiovascular system. One of the most important factors that contribute to cardiac fibrosis is angiotensin II (Ang II). Accumulating studies have suggested that reactive oxygen species (ROS) plays an important role in cardiac fibrosis and sodium tanshinone IIA sulfonate (STS) possesses antioxidant action. We therefore examined whether STS depresses Ang II-induced collagen type I expression in cardiac fibroblasts. In this study, Ang II significantly enhanced collagen type I expression and collagen synthesis. Meanwhile, Ang II depressed matrix metalloproteinase-1 (MMP-1) expression and activity. These responses were attenuated by STS. Furthermore, STS depressed the intracellular generation of ROS, NADPH oxidase activity and subunit p47phox expression. In addition, N-acetylcysteine the ROS scavenger, depressed effects of Ang II in a manner similar to STS. In conclusion, the current studies demonstrate that anti-fibrotic effects of STS are mediated by interfering with the modulation of ROS.  相似文献   
74.
The concept of Koszulity for differential graded (DG, for short) modules is introduced. It is shown that any bounded below DG module with bounded Ext-group to the trivial module over a Koszul DG algebra has a Koszul DG submodule (up to a shift and truncation), moreover such a DG module can be approximated by Koszul DG modules (Theorem 3.6). Let A be a Koszul DG algebra, and Dc(A) be the full triangulated subcategory of the derived category of DG A-modules generated by the object AA. If the trivial DG module...  相似文献   
75.
胡倩  胡尧  刘伟 《经济数学》2020,37(4):123-129
应用主成分估计方法,对Logistic回归模型进行参数估计,并消除多重共线性影响.首先选取了累计贡献率达到85%以上的6个主成分,对因变量进行主成分估计,然后挑选出冠心病患者发病的主要影响因素,最后得到了因变量(冠心病发病)与6个主要影响因素(血压(sbp)、累计烟草量(tobacco)、低密度脂蛋白胆固醇(ldl)、心脏病家族史(famhist)、型表现(typea)和发病年龄(age))的回归模型.根据结果可知,心脏病家族史是导致心脏病发病最大的一个原因,它是一个不可控因素;在可控因素中,累计烟草量对冠心病发病的影响最大,因此建议患者应该控制烟草摄入量,以保证病情的稳定性.  相似文献   
76.
Summary Deprenyl metabolites were analyzed in various organs of rats after chronic oral treatment. The investigation was carried out by gas chromatography combined with MSD after derivatization of the metabolites. When (−)-deprenyl (selegiline) was administered to rats higher ratios of methamphetamine to amphetamine were found in the kidney, and the heart at 1 and 5 h after treatment, than after (+)-deprenyl administration. Both deprenyl and its demethylated metabolite were also detected; however, their level was generally lower than that of either methamphetamine or amphetamine. Coadministration of verapamil with selegiline did not essentially alter the major metabolic pathway of deprenyl metabolism.  相似文献   
77.
为评价冠心病及高心病的Q-T离散度的临床意义,观察了97例冠心病、高心病患者的Q-T离散度,并与96例正常组对比。结果表明,冠心病,高心病患者的QTd、Q-Tcd、J-Td、J-Tcd均比正常组延长,有显著差异,P〈0.01。  相似文献   
78.
风险分析中的信息扩散及其参数优化   总被引:5,自引:0,他引:5  
在进行风险分析和评估过程中,经常遇到样本信息不充分,数据不完备,即小样本问题.本文一,用信息扩散方法对两个具体项目进行分析处理,由于篇幅有限文中仅介绍一个.二在黄崇福教授提出的信息扩散基础上,提出两个优化准则,即波动最小准则和有限偏离度准则,应用优化方法,求得参数最优解,结果是十分理想的.  相似文献   
79.
In liquid chromatography with “low-dispersion methods”, there is an increasing need to reproducibly inject nanoliter sample volumes. Low-dispersion methods produce very narrow peaks because of short column length, narrow column bore, small particle packing, low particle surface area, open tubular configuration, or combinations of these parameters. This paper describes a new injector method, the “groove-injector” which involves simple plumbing changes for use of a conventional multi-port valve (8-ports or more) to inject sample volumes approximating a single groove in such a valve (e.g 30 nanoliters with aceptable reproducibility, ca. 8% RSD). In addition, by changing a resistor, volumes between 30, and over 2,000 nanoliters (nearly two orders of magnitude) can be injected with reproducibilities generally below 2% RSD. Different samples can be injected by using an autosampler. Compared to commonly used 4-port valves for nanoliter injections, multi-port valves have a number of advantages. Multiport valves generally are more commonly available and they are a better financial investment because of their versatility for column switching, sample enrichment, or variable volume injections. Previously, submicroliter (nanoliter) injections have not been possible with multi-port valves in as direct and simple a manner as described here.  相似文献   
80.
Congestive heart failure (CHF) is a chronic cardiovascular condition associated with dysfunction of the autonomic nervous system (ANS). Heart rate variability (HRV) has been widely used to assess ANS. This paper proposes a new HRV analysis method, which uses information-based similarity (IBS) transformation and fuzzy approximate entropy (fApEn) algorithm to obtain the fApEn_IBS index, which is used to observe the complexity of autonomic fluctuations in CHF within 24 h. We used 98 ECG records (54 health records and 44 CHF records) from the PhysioNet database. The fApEn_IBS index was statistically significant between the control and CHF groups (p < 0.001). Compared with the classical indices low-to-high frequency power ratio (LF/HF) and IBS, the fApEn_IBS index further utilizes the changes in the rhythm of heart rate (HR) fluctuations between RR intervals to fully extract relevant information between adjacent time intervals and significantly improves the performance of CHF screening. The CHF classification accuracy of fApEn_IBS was 84.69%, higher than LF/HF (77.55%) and IBS (83.67%). Moreover, the combination of IBS, fApEn_IBS, and LF/HF reached the highest CHF screening accuracy (98.98%) with the random forest (RF) classifier, indicating that the IBS and LF/HF had good complementarity. Therefore, fApEn_IBS effusively reflects the complexity of autonomic nerves in CHF and is a valuable CHF assessment tool.  相似文献   
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