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981.
氟是自然界广泛分布的元素之一,它以各种化学形态广泛分布于土壤、水和空气中,几乎所有的动植物体内均含氟,在自然界的氟常以无机或有机化合物形式存在。随着科学的发展、社会的进步,纯净水、直饮水已走进寻常百姓家中,走进学校、工厂机关,给人们带来便利。但也有学者提出,纯净水对人 相似文献
982.
983.
Zengyan Wang Jiao Li Xicheng Wang Mei Liu Man Liao Changdong Zhang Xiaoke Shang 《Annals of noninvasive electrocardiology》2022,27(2)
BackgroundPulmonary arterial hypertension (PAH) is a complex and severe complication of connective tissue disease (CTD). We aimed to evaluate the application value of myocardial perfusion imaging (MPI) in evaluating CTD‐associated PAH (CTD‐PAH).MethodsWe retrospectively included 88 patients who were diagnosed with CTD between January 2018 and December 2020 at our hospital. Fifty‐eight patients had PAH and were included into the CTD‐PAH group. Thirty patients without PAH were included in the control group. All patients received routine physical examination, biochemical tests and cardiac function evaluation, right heart catheterization (RHC), and 99mTc‐MIBI MPI. PAH patients were divided into the mild, moderate, and severe PAH group according to their mean pulmonary artery pressures by RHC. Pearson correlation analysis was used to calculate the correlation between the right ventricle target/background (T/B) and right ventricle stroke volume (RV‐SV), total pulmonary resistance (TPR), pulmonary vascular resistance (PVR), mean pulmonary arterial pressure (mPAP), 6‐minute walk distance (6‐MWD), and N‐terminal B‐type natriuretic peptide (NT‐proBNP). The ROC curves of T/B and pulmonary artery pressure classification were plotted and the sensitivity and specificity of T/B in diagnosing PAH of different severities were analyzed.ResultsThe analysis of correlation revealed that T/B correlated negatively with 6‐MWD and positively with NT‐proBNP and exhibited good positive correlation with mPAP, TPR, and PVR by RHC and negative correlation with RV‐SV. T/B was of the most diagnostic value for severe PAH, and its correlation with severe PAH was stronger than that with mild PAH and moderate PAH.ConclusionsTarget/background is a noninvasive method that can simultaneously evaluate pulmonary arterial pressure and myocardial perfusion of CTD‐CHD patients and is particularly of relatively high value for severe PAH patients. 相似文献
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985.
986.
廖桂莲 《国际医药卫生导报》2007,13(20):26-29
目的 探讨子宫肌瘤患者的心理健康状况及其影响因素.方法 选取2005年5月~2007年5月在我院诊治的52例子宫肌瘤患者,同期选择68例非子宫肌瘤的健康人作对照,利用焦虑自评量表(self-rating anxiety scale,SAS)和抑郁自评量表(self-rating depression scale.SDS)进行调查.结果 肌瘤组焦虑、抑郁评分明显高于对照组(P<0.001).肌瘤组文化程度在初中以上者SAS、SDS评分高于初中及以下者(P<0.001,P<0.05),月经量增多者SAS、SDS评分高于月经量正常者(P<0.05),而在发病对问及年龄方面,SAS、SDS评分无显著性差异.结论 子宫肌瘤患者存在一定的焦虑、抑郁症状,应积极开展心咨询及心理治疗,提高患者的生活质量. 相似文献
987.
988.
989.
目的 评价各种数据缺失机制对逐步回归变量筛选结果的影响.方法 通过模拟产生不同缺失机制和缺失类型的数据,用筛选到的真实变量的个数和损失函数大小作为指标,评价其对逐步同归的影响.结果 完整数据情况下的筛选表现优于各缺失机制卜表现;缺失类型比缺失机制对筛选结果的影响更为明显.结论用逐步回归对含缺失值的数据进行变量筛选时,需要关注缺失机制和缺失类型. 相似文献
990.
Ying Liao Xueying Li Yanwu Zhang Stella Chen Chaoshu Tang Junbao Du 《Acta paediatrica (Oslo, Norway : 1992)》2009,98(7):1194-1200
Aim: The present study was aimed at evaluating present randomized controlled trials (RCTs) regarding the effect of α-adrenoceptor agonists on vasovagal syncope (VVS).
Methods: According to inclusion and exclusion criteria, articles were selected from medical electronic databases. RCTs were then assessed based on the Juni assessment, and meta-analysis was completed using the Review Manager 4.2 software. Indication to further evaluate effects was the recurrence of syncope during follow-up treatment or a response in the head-up tilt test (HUT) after treatment. The results were stated as odd ratio (OR), with a 95% confidence interval (CI) and a
p < 0.05 significant level.
Results: In total, six RCTs were selected. Funnel plot analysis showed possible publication bias. Meta-analysis of the six RCTs, including all 165 patients in the treatment group and 164 patients in the control group, indicated that α-adrenoceptor agonists were more effective than placebos in treating VVS (OR = 0.21, 95% CI: 0.06–0.77, p = 0.02). The further, weighted independent t- test disclosed that the weighted mean percentage of responders for midodrine (76.3%± 7.7%) was significantly higher than that for etilefrine (65.5%± 15.4%) ( t = 5.863, p < 0.001).
Conclusion: The currently published RCTs support that α-adrenoceptor agonists might be effective for VVS. Midodrine can be regarded as a better choice compared with etilefrine. 相似文献
Methods: According to inclusion and exclusion criteria, articles were selected from medical electronic databases. RCTs were then assessed based on the Juni assessment, and meta-analysis was completed using the Review Manager 4.2 software. Indication to further evaluate effects was the recurrence of syncope during follow-up treatment or a response in the head-up tilt test (HUT) after treatment. The results were stated as odd ratio (OR), with a 95% confidence interval (CI) and a
p < 0.05 significant level.
Results: In total, six RCTs were selected. Funnel plot analysis showed possible publication bias. Meta-analysis of the six RCTs, including all 165 patients in the treatment group and 164 patients in the control group, indicated that α-adrenoceptor agonists were more effective than placebos in treating VVS (OR = 0.21, 95% CI: 0.06–0.77, p = 0.02). The further, weighted independent t- test disclosed that the weighted mean percentage of responders for midodrine (76.3%± 7.7%) was significantly higher than that for etilefrine (65.5%± 15.4%) ( t = 5.863, p < 0.001).
Conclusion: The currently published RCTs support that α-adrenoceptor agonists might be effective for VVS. Midodrine can be regarded as a better choice compared with etilefrine. 相似文献