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1.
目的探讨钆塞酸二钠(Gadolinium ethoxybenzyl diethylene-triamine-pentaacetic-acid,Gd-EOB-DTPA)动态对比增强MRI(dynamic contrast-enhanced magnetic resonance imaging,DCE-MRI)定量评估大鼠中度肝纤维化(hepatic fibrosis,HF)的价值。材料与方法40只雄性Wistar大鼠(对照组10只,实验组30只),腹腔注射CCl4构建不同分期HF模型,并行肝脏轴位T1WI及DCE-MRI扫描,获取以下参数:容量转运常数(Ktrans)、速率常数(Kep)、血管外细胞外间隙体积百分数(Ve)以及初始曲线下面积(iAUC)。所有大鼠扫描前行尾静脉采血,测定血清中透明质酸(hyaluronic acid,HA)、层粘连蛋白(laminin,LN)含量。扫描结束后取大鼠肝脏组织进行HF病理学分期。采用独立样本t检验比较正常组与实验组、正常组及轻度HF组与中度HF组DCE-MRI参数和血清学指标的差异;采用单因素方差分析比较DCE-MRI参数和血清学指标在不同HF分期之间的差异;采用Spearman相关检验分析DCE-MRI参数和血清学指标与HF分期的相关性;利用ROC曲线比较各参数诊断中度HF的价值。结果26只大鼠纳入本次研究,其中病理学分期为正常组6只、轻度HF(F1期)7只、中度HF(F2~F3期)13只,随着HF加重,Ktrans、Kep、Ve及iAUC均降低(r=-0.665,P<0.001;r=-0.395、P=0.046;r=-0.565、P=0.003;r=-0.538、P=0.005),血清LN及HA含量均升高(r=0.606,P=0.001;r=0.601,P=0.001);Ktrans、Ve及iAUC在实验组与正常组、正常组及轻度HF组与中度HF组、正常组与中度HF组、轻度HF与中度HF组间差异均有统计学意义(P<0.05);血清LN及HA含量在对照组与中度HF组之间差异具有统计学意义(P<0.05);ROC曲线显示Ktrans及LN诊断中度HF效能最高。结论Gd-EOB-DTPA DCE-MRI定量评估对中度HF分期具有较好的诊断价值,其中DCE-MRI参数中Ktrans具有最佳的诊断效能。  相似文献   
2.
目的比较美国BD Bactec树脂需氧瓶和溶血素厌氧瓶与法国梅里埃BacT/Alert树脂血培养瓶的抗生素吸附能力。方法选用临床常用抗生素:亚胺培南、万古霉素、氨苄西林、头孢曲松、甲硝唑、美罗培南、米卡芬净,按照一定浓度与标准菌株和无菌羊血混合,同时接种于2种品牌血培养瓶,记录不同血培养瓶五天内的阳性报警情况及检出时间,对比各血培养瓶的抗生素吸附能力。结果需氧瓶组:氨苄西林BMX-FA与BD-FA瓶检出率相同,均为100%,且BMX-FA较BD-FA瓶检出时间长(11.04±0.24 h vs 10.45±0.45 h),差异有统计学意义(t=2.59,P<0.05);含亚胺培南及头孢曲松组中,2种血培养瓶均未检出;含万古霉素组,BD-FA 比BMX-FA瓶的检出率低,分别为40%和100%,且BMX-FA 比BD-FA瓶的检出时间更短(15.70±0.76 h vs 21.50±0.71 h)差异有统计学意义(P<0.05);含米卡芬净组,BD-FA 比 BMX-FA瓶的检出率低,分别为60%和100%,且BMX-FA比BD-FA瓶检出时间更短(61.06±10.42 h vs 94.20±1.74h),差异有统计学意义(t=12.49,7.01,P<0.05)。厌氧瓶组:含亚胺培南、万古霉素、氨苄西林、甲硝唑、美罗培南的BD-FN瓶均未检出,BMX-FN瓶检出率均为100%;含头孢曲松组,2种血培养瓶均未检出。结论法国梅里埃BacT/Alert树脂血培养瓶的抗生素吸附能力总体上优于美国BD Bactec树脂需氧瓶和溶血素厌氧瓶,临床可根据抗生素使用情况选择合适的血培养瓶。  相似文献   
3.
背景 运动能力是血液透析患者强有力的死亡预测因子。因此,寻求便捷且有效的评价工具以实现患者运动能力的评估是目前迫切需要探讨的问题。 目的 在中国与英国血液透析患者中对杜克活动状况指数(DASI)与日常体力活动问卷(GPPAQ)中的步速问题进行效度检验。 方法 于2018年1月至2020年9月,选取中国某大学附属医院血液透析患者40例与英国莱斯特肾脏病网络系统血液透析患者39例。采用DASI和GPPAQ的步速问题评估患者的运动能力与步速,同时采用往返行走试验(SWT)与简易机体功能评估(SPPB)的步速测试对患者进行测试验证。DASI的效度检验采用相关性分析,GPPAQ步速问题的效度检验采用方差分析。 结果 中国与英国血液透析患者的DASI和递增负荷往返行走试验(ISWT)呈正相关(r中国=0.39,rs英国=0.60;P<0.05),和耐力往返步行试验(ESWT)无相关关系(P>0.05)。根据GPPAQ中步速问题的自我评估结果,将中国血液透析患者归为慢速、平稳步速、轻盈步速、快速4类,4类患者客观测量的SPPB步速范围存在重叠,平均SPPB步速比较,差异无统计学意义(P>0.05);将英国血液透析患者归为慢速、平稳步速、轻盈步速3类,3类患者客观测量的平均SPPB步速比较,差异有统计学意义(P<0.05),其中自我评估为慢速患者的平均SPPB步速低于自我评估为平稳步速、轻盈步速者(P<0.05)。 结论 DASI可以有效测量中国与英国血液透析患者的运动能力。在两个不同文化群体中,GPPAQ的步速问题均无法协助患者准确报告自身步速,但在区分"慢"与"不慢"的步速上具有一定潜在效用。  相似文献   
4.
Alveoli are the basic structure of the lungs, consisting of various types of parenchymal and bone marrow-derived cells including alveolar macrophages. These various types of cells have several important functions; thus, communication between these cells plays an important role in homeostasis as well as in the pathophysiology of diseases in the lungs. For a better understanding of the pathophysiology of lung diseases, researchers have isolated each type of lung cell to investigate the changes in their gene expressions, including their humoral factor or adhesion molecules, to reveal the intercellular communication among these cells. In particular, investigations during the past decade have focused on extracellular vesicles, which are lipid bilayer delimited vesicles released from a cell that can move among various cells and transfer substances, including microRNAs, mRNAs and proteins, thus, functioning as intercellular messengers. Extracellular vesicles can be classified into three general groups: apoptotic bodies, exosomes, and microparticles. Extracellular vesicles, especially exosomes and microparticles, are attracting increasing attention from pulmonologists as tools for understanding pathogenesis and disease diagnosis. Here, we review studies, including our own, on exosomes and microparticles and their roles in both lung homeostasis and the pathogenesis of lung diseases such as idiopathic pulmonary fibrosis, chronic obstructive lung diseases, and acute respiratory distress syndrome. This review also addresses the roles of extracellular vesicles in COVID-19, the current global public health crisis.  相似文献   
5.
ObjectivesThis study sought to determine the relationship between the severity of reduced quantitative perfusion parameters and mortality with and without revascularization.BackgroundThe physiological mechanisms for differential mortality risk of coronary flow reserve (CFR) and coronary flow capacity (CFC) before and after revascularization are unknown.MethodsGlobal and regional rest-stress (ml/min/g), CFR, their regional per-pixel combination as CFC, and relative stress in ml/min/g were measured as percent of LV in all serial routine 5,274 diagnostic PET scans with systematic follow-up over 10 years (mean 4.2 ± 2.5 years) for all-cause mortality with and without revascularization.ResultsSeverely reduced CFR of 1.0 to 1.5 and stress perfusion ≤1.0 cc/min/g incurred increasing size-dependent risks that were additive because regional severely reduced CFC (CFCsevere) was associated with the highest major adverse cardiac event rate of 80% (p < 0.0001 vs. either alone) and a mortality risk of 14% (vs. 2.3% for no CFCsevere; p = 0.001). Small regions of CFCsevere ≤0.5% predicted high risk (p < 0.0001 vs. no CFCsevere) related to a wave front of border zones at risk around the small most severe center. By receiver-operating characteristic analysis, relative stress topogram maps of stress (ml/min/g) as a fraction of LV defined these border zones at risk or for mildly reduced CFC (area under the curve [AUC]: 0.69) with a reduced relative tomographic subendocardial-to-subepicardial ratio. CFCsevere incurred the highest mortality risk that was reduced by revascularization (p = 0.005 vs. no revascularization) for artery-specific stenosis not defined by global CFR or stress perfusion alone.ConclusionsCFC is associated with the size-dependent highest mortality risk resulting from the additive risk of CFR and stress (ml/min/g) that is significantly reduced after revascularization, a finding not seen for global CFR. Small regions of CFCsevere ≤0.5% of LV also carry a high risk because of the surrounding border zones at risk defined by relative stress perfusion and a reduced relative subendocardial-to-subepicardial ratio.  相似文献   
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7.
Background and objectiveChronic Obstructive Pulmonary Disease (COPD) causes substantial morbidity and mortality across the globe. Diagnosis of COPD requires post-bronchodilator FEV1/FVC <0.70 as per GOLD Guidelines. FVC maneuver requires a minimum of 6 seconds of forceful expiration with no flow for 1 second for an accepted effort, which lacks any fixed cut-off point. This leads to discomfort, especially in advanced COPD and old aged population. We conducted this study to find the utility of FEV1/FEV6 as a surrogate for FEV1/FVC, the correlation between the two ratios, and the fixed cut-off value of FEV1/FEV6 for COPD diagnosis.MethodsThis was a prospective, cross-sectional study approved by the institutional ethics committee conducted from January 2017 to November 2018. Consented patients above 18 years suspected of COPD underwent Spirometry as per ATS guidelines. FEV1, FEV6, FEV1/FEV6 and FEV1/FVC ratios were recorded from the best acceptable maneuver.ResultsOut of 560 screened patients, 122 diagnosed as COPD. The correlation coefficient between the post-bronchodilator FEV1/FVC ratio and FEV1/FEV6 ratio was 0.972 (p < 0.01). The relationship between the post-bronchodilator FEV1/FVC ratio and FEV1/FEV6 ratio (linear regression analysis) was found out as: FEV1/FVC = ?1.845 + 1.009(FEV1/FEV6). Using this formula, the post-bronchodilator FEV1/FEV6 value of 71.845 was obtained corresponding to the post-bronchodilator FEV1/FVC value of 70.00.ConclusionWe found a positive correlation coefficient (r = 0.972, p < 0.001) between the FEV1/FEV6 and FEV1/FVC ratios and the cut off value of 71.845 (p < 0.01) for the post-bronchodilator FEV1/FEV6 ratio for the diagnosis of COPD. Thus FEV1/FEV6 should be used as a surrogate for FEV1/FVC for the diagnosis of COPD.  相似文献   
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9.
目的:调查全国精神科医师转岗培训情况,为优化精神科医师转岗培训和制定精神卫生人才培养体系建设提供参考。方法:设计精神科医师转岗培训调查问卷,调查全国31个省(自治区、直辖市)和新疆生产建设兵团2015-2020年转岗培训情况。采用描述性分析方法,对全国精神科医师转岗培训和培训区县覆盖等情况进行分析;采用χ~2检验比较东中西部地区转岗医师中已提供精神科诊疗服务情况。结果:全国共13 388人完成精神科医师转岗培训,9923人变更或加注了精神科执业资质,6538人已提供精神科诊疗服务,无精神卫生资源空白区县数减少85.1%。结论:转岗培训短期内缓解了精神卫生人才紧缺现状,提高了精神卫生服务可及性。  相似文献   
10.
Cardiac rehabilitation programs consisting of core features of exercise training for patients with heart failure have demonstrated a wide range of physical and psychological benefits. In study, a meta‐analysis of combined aerobic and resistance training was conducted on various outcomes in patients with heart failure. Database searches included EMBASE, PubMed, Medline, Cochrane Library, Web of Science, OVID, and CINAHL. Only randomized, controlled trials were included. Review Manager 5.3 software was used to perform the meta‐analysis. In total, 12 studies and 516 patients were included. The results demonstrated that combined aerobic and resistance training is effective in promoting exercise capacity, muscle strength, and 6 min walk distance. Furthermore, combined training significantly improves the quality of life of patients with heart failure. However, there was no significant difference found for outcomes of depression and sleep. Future studies with rigorous methodological designs and long‐term follow ups are recommended to evaluate the sustainable benefits of combined aerobic and resistance intervention programs.  相似文献   
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