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121.
Abstract

This study was undertaken to compare the concentrations of pro- and anti-angiogenic growth factors, nitric oxide (NO) stable metabolites in maternal serum and embryonic left ventricular (LV) isovolumic relaxation time (IRT, ms) during the first trimester in two groups of women: with pregnancy conceived by assisted reproductive technologies (ART, n?=?39) and normally conceived (control group, n?=?68) pregnancy. The concentration of vasoconstrictor endothelin 1 was 45.5 times more in ART than in control group. On the contrary, the concentrations of NO stable metabolites in ART were 1.9 times less than in control women. The assessment of angiogenic suppressors in ART women demonstrates the decrease in s-endoglin concentration was 1.6 times and in soluble receptor to vascular endothelial growth factor concentration was 2.0 times in comparison with control group. There was a significant increase in LV IRT in ART embryos in comparison to control ones. These data suggest significant changes in pro- anti-angiogenic factors balance and increase in vascular impedance in ART-conceived embryos.  相似文献   
122.
Chemical exchange saturation transfer (CEST) MRI is sensitive to labile proton concentration and exchange rate, thus allowing measurement of dilute CEST agent and microenvironmental properties. However, CEST measurement depends not only on the CEST agent properties but also on the experimental conditions. Quantitative CEST (qCEST) analysis has been proposed to address the limitation of the commonly used simplistic CEST‐weighted calculation. Recent research has shown that the concomitant direct RF saturation (spillover) effect can be corrected using an inverse CEST ratio calculation. We postulated that a simplified qCEST analysis is feasible with omega plot analysis of the inverse CEST asymmetry calculation. Specifically, simulations showed that the numerically derived labile proton ratio and exchange rate were in good agreement with input values. In addition, the qCEST analysis was confirmed experimentally in a phantom with concurrent variation in CEST agent concentration and pH. Also, we demonstrated that the derived labile proton ratio increased linearly with creatine concentration (P < 0.01) while the pH‐dependent exchange rate followed a dominantly base‐catalyzed exchange relationship (P < 0.01). In summary, our study verified that a simplified qCEST analysis can simultaneously determine labile proton ratio and exchange rate in a relatively complex in vitro CEST system. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
123.
124.
The World Health Organization has reported an annual global suicide rate of 14.5 per 100,000 people. On the other hand, it is estimated that approximately one‐third of the global population are infected with Toxoplasma gondii (T. gondii) parasite. It is widely assumed that microbial pathogens, such as T. gondii, are probably associated with affective and behavioural modulation. The present article aimed to assess the proposed role of toxoplasmosis in raising the risk of suicidal ideation (SI) and suicide attempts (SA) using the available epidemiological data. Seven major electronic databases and the Internet search engine Google were searched for all the studies published between the 1st of January 1950 and 31st of October 2019. The heterogeneity and the risk of bias within and across studies were assessed. Following data extraction, pooled odds ratios (ORs) with 95% confidence interval (CI) across studies were calculated using the random‐effects models. A total number of 9,696 articles were screened and 27 studies were regarded as eligible in our systematic review (SI with five papers and 22 papers on SA). A significant association was detected between antibodies against T. gondii with TA (ORs = 1.57; 95% confidence interval [CI] 1.23–2.00, p = .000). Exploration of the association between T. gondii and SA yielded a positive effect of seropositivity for IgG antibodies but not IgM. Despite the limited number of studies, a statistical association was detected between suicidal behaviours and infection with latent T. gondii.  相似文献   
125.
目的分析新生儿重症监护病房(NICU)中重症肺炎新生儿多种菌感染危险因素。方法回顾分析2014年1月至2019年5月收入NICU的1 057例重症细菌肺炎新生儿的临床资料,分析其多种菌感染的危险因素。结果单因素分析显示,胎龄(37周)、出生体质量(2 500 g)、发病日龄(7 d)、羊水污染(Ⅱ、Ⅲ度)、感染类型(医院感染)、住院时间(≥14天)、机械通气、Apagar评分(7分)、胎膜早破、抗菌药物使用天数(≥10天)、更换抗菌药物(≥3种)、联合使用抗菌药物(≥3种)12个因素是NICU中重症肺炎新生儿多种菌感染的危险因素,差异有统计学意义(P均0.05)。多因素分析显示,更换抗菌药物(≥3种)、Apagar评分(7分)、感染类型(医院感染)、机械通气、羊水污染(Ⅱ、Ⅲ度)是NICU中重症肺炎新生儿多种菌感染的独立危险因素(P0.05)。结论临床应针对主要危险因素采取综合防控措施,减少NICU新生儿重症肺炎多种菌感染。  相似文献   
126.
目的鉴定河南省1例来自柬埔寨的登革热输入性病例的登革病毒(dengue virus,DENV)血清型和基因型及其序列特征和传播来源。方法患者血液标本来源于2019年国家疾病监测系统网络直报的登革热疑似病例。样品经快速检测DENV NS1抗原和IgM/IgG抗体,再提取血清中核酸,应用荧光RT-PCR法进行DENV血清型鉴定,同时用Vero和BHK-21细胞对血清标本进行病毒分离培养,阳性培养物扩增全基因组序列,进行序列系统进化分析。结果该病例实验室确诊为DENV 1型感染,并从血清标本中分离到病毒株,测序后拼接成全长10670 nt的全基因组序列,经系统进化分析,该病毒株属于DENV 1型基因Ⅰ型,与东南亚流行株具有较高同源性和较近亲缘关系。结论2019年河南省来自柬埔寨的输入性病例的病原体为DENV 1型基因I型,此为近年来东南亚输入我国的常见血清型和基因型。  相似文献   
127.
目的构建稽留流产(missed abortion,MA)患者在孕早期流产危险因素列线图。方法纳入2017年2月至2019年10月因稽留流产于中国建筑第二工程局职工医院治疗的孕妇125例为研究组,随机纳入同时期正常孕妇126例为对照组,分析两组患者临床基本资料:年龄、环境因素、动物接触史、叶酸使用、文化程度、流产情况、疾病史、激素水平等。采用Logistic回归分析对孕早期发生稽留流产的危险因素进行分析,应用R软件建立孕早期稽留流产预测列线图,并进行验证。结果研究组孕妇年龄、睾酮(testosterone,T)水平高于对照组,而催乳素(prolactin,PRL)、雌二醇(estradiol,E2)、孕酮(progesterone,P)水平低于对照组,差异均有统计学意义(P<0.05);Logistic回归分析提示孕妇年龄(OR=1.809,P=0.003)、吸烟饮酒(OR=78.120、P=0.044)、职业暴露(OR=61.238,P=0.021)、T水平(OR=5.432,P=0.001)是孕早期发生MA的危险因素。PRL(OR=0.376,P=0.003)、E2(OR=0.258,P=0.016)、P(OR=0.396,P=0.005)是孕早期发生MA的保护因素。预测孕早期MA发生的相关危险因素的C-index为0.912(95%CI:0.874-0.943)。结论列线图中孕妇年龄、环境因素、激素水平能较准确的预测孕早期发生MA的风险。  相似文献   
128.
Background  Limited research exists on patient knowledge/cognition or “getting inside patients'' heads.” Because patients possess unique and privileged knowledge, clinicians need this information to make patient-centered and coordinated treatment planning decisions. To achieve patient-centered care, we characterize patient knowledge and contributions to the clinical information space. Methods and Objectives  In a theoretical overview, we explore the relevance of patient knowledge to care provision, apply historical perspectives of knowledge acquisition to patient knowledge, propose a representation of patient knowledge types across the continuum of care, and include illustrative vignettes about Mr. Jones. We highlight how the field of human factors (a core competency of health informatics) provides a perspective and methods for eliciting and characterizing patient knowledge. Conclusion  Patients play a vital role in the clinical information space by possessing and sharing unique knowledge relevant to the clinical picture. Without a patient''s contributions, the clinical picture of the patient is incomplete. A human factors perspective informs patient-centered care and health information technology solutions to support clinical information sharing.  相似文献   
129.
Human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) is one of the leading causes of morbidity and mortality in West Africa. Prevalence among the most productive age group in West and Central Africa stood at 1.5%, 3.4.0%, 2.5%, and 2.1% in 1990, 2000, 2010, and 2015 respectively. This study examined the effect of HIV/AIDS on economic growth in West Africa with focus on 11 countries. The augmented Solow model, rooted in the neoclassical growth theory, was used, which was operationalized using dynamic panel data modeling approach. Incidence, prevalence, number of people living with HIV/AIDS (PLWHA), and AIDS‐related deaths were used to measure HIV/AIDS. Estimations using system GMM returned statistically significant results while those of first difference and difference GMM were not. From the outcome of system GMM analysis, a percentage increase in incidence, prevalence, PLWHA, and AIDS deaths correspondingly reduced growth significantly through their effects on life expectancy by 0.15%, 0.02%, 0.004%, and 0.03%. Acquired immune deficiency syndrome deaths and PLWHA lowered economic growth through enrolment but not significantly. The import of the findings is that HIV/AIDS threatens growth through life expectancy in West Africa. Therefore, its spread in the subregion should be effectively contained while proper treatment should be provided for all infected persons.  相似文献   
130.
Congenital heart disease is a rare but important finding in adults who experience sudden death. Examination of the congenitally malformed heart has historically been considered esoteric and best left to those with expertise. The Cardiac Risk in the Young cardiovascular pathology laboratory based at St George's University of London has now received over 6,000 cases. Of these, 21 congenitally malformed hearts were retained for research and educational purposes. Hearts were assessed using sequential segmental analysis, and causes of death were adjudicated based on thorough macroscopic examination and histology. Congenital malformations that were encountered included atrial septal defects, ventricular septal defects, tetralogy of Fallot, and transposition of the great arteries in both its regular and congenitally corrected variants. Findings also included hearts with mirror-imaged and isomeric atrial appendages. Direct causes of death included myocardial fibrosis, pulmonary hypertension, and hemorrhage. A small but notable proportion did not reveal a substrate for arrhythmia, raising the question of whether the terminal event was due to the congenital heart disease itself, or an underlying channelopathy. Here, we demonstrate the value of simple sequential segmental analysis in describing and categorizing the cases, with the concept of the “morphological method” serving to identify the distinguishing features of the cardiac components. Clin. Anat. 33:394–404, 2020. © 2019 Wiley Periodicals, Inc.  相似文献   
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