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991.
In this work, a new two-stage approach to the deposition of high-entropy alloy coatings is proposed. At the first stage, a composite precursor coating is formed by detonation spraying of the metal powder mixtures. At the second stage, the precursor coating is re-melted by a laser, and the formation of multi-component solid solution phases can be expected upon solidification. The feasibility of the proposed approach was validated using three different mixtures of Fe, Ni, Cu, Co and Al powders. It was shown that detonation spraying allows forming composite coatings with a uniform distribution of the lamellae of different metals. The results of the structural analysis of the laser-treated coatings suggest that complete alloying occurred in the melt and face-centered cubic solid solutions formed in the coatings upon cooling.  相似文献   
992.
993.
994.
Rationale:The treatment of dilated cardiomyopathy (DCM) has recently been greatly improved, especially with the widespread use of sacubitril/valsartan (ARNI) combination therapy. We know that ARNI-like drugs can significantly improve the symptoms of heart failure with reducing ejection fraction. However, clinical studies evaluating the safety and efficacy of ARNI in DCM-associated arrhythmia are limited, and whether individuals with arrhythmia would benefit from ARNI remains controversial. In this case, we report a patient with complete left bundle branch block (CLBBB) associated with DCM whose CLBBB returned to normal after treatment with ARNI.Patient concerns:A 38-year-old man was admitted to the hospital for 20 days for idiopathic paroxysmal dyspnea. He presented with exacerbated dyspnea symptoms at night, accompanied by cough and sputum.Diagnosis:Physical examination revealed a grade 4/6 systolic murmur could be heard in the apical area of the heart and mild edema was present in both lower limbs. Laboratory examination found that the B-type natriuretic peptide was significantly increased. Echocardiography indicated left atrial internal diameter, right ventricular internal diameter, and left ventricular diastolic diameter were enlarged and ejection fraction was significantly decreased. Besides, the pulsation of the wall was diffusely attenuated. Electrocardiogram was suggestive of tachycardia and CLBBB. A diagnosis of DCM with CLBBB was considered based on a comprehensive evaluation of the physical examination, laboratory examination, echocardiography and electrocardiogram.Interventions:The patient was treated with ARNI at a dose of 50 mg (twice a day) at first, gradually increasing to the target dose (200 mg, twice a day) in the following 9 months as shown in Table Table1,1, along with metoprolol 25 mg (once a day [qd]), diuretics 20 mg (qd), and aldosterone 20 mg (qd).Table 1Specific medications used in treatment.
Month(s) and dates after dischargeMorning (ARNI)Night (ARNI)Metoprolol 23.75 mg QD;
diuretics (furosemide) 20 mg QD;
aldosterone 20 mg QD
Month 1 (28/02/20–27/03/20)50 mg50 mg
Month 2 (27/03/20–26/04/20)100 mg50 mg
Month 3–4 (26/04/20–28/06/20)100 mg100 mg
Months 5–7 (28/05/20–29/08/20)150 mg100 mg
Months 8–11 (29/08/20–13/11/20)150 mg150 mg
Month 11–present (13/11/20–)200 mg200 mg
Open in a separate windowARNI = sacubitril/valsartan, QD = once a day.Outcomes:After treatment with ARNI during the 9-month follow-up, the patient’s symptoms improved, and CLBBB returned to normal.Lessons:Clinical studies evaluating the safety and efficacy of ARNI in DCM-associated arrhythmia are limited, and whether individuals with arrhythmia would benefit from ARNI remains controversial. This report will help to instruct the clinical treatment of DCM patients with CLBBB and the potential application of ARNI.  相似文献   
995.
Background:The 2020 European Society of Cardiology guidelines do not recommend pretreatment for nonST-segment elevation myocardial infarction (NSTEMI) patients with unclear coronary anatomy, which is inconsistent with our routine preoperative approach to loading P2Y12 receptor inhibitors (e.g., preoperative loading of 300 mg of clopidogrel).Objectives:The purpose of our study was to compare the safety and effectiveness of P2Y12 inhibitors administered before coronary angiography or at least before percutaneous coronary intervention (PCI) with during or after PCI.Methods:Cochrane, PubMed, and Embase databases were searched. The primary effect endpoint and safety endpoint were any-cause death and major bleeding, respectively. Major adverse cardiovascular events, myocardial infarction and revascularization were also analyzed.Results:Our search identified 9 trials. P2Y12 inhibitor pretreatment was associated with lower death from any cause (OR 0.62, 95% CI 0.53–0.72, P < 0.00001) without increasing the risk of bleeding (OR 1.02, 95% CI 0.80–1.30, P = 0.89). However, prasugrel or ticagrelor pretreatment was not associated with a lower risk of mortality (OR 0.70, 95% CI 0.31–1.59, P = 0.40) and increased the risk of bleeding (OR 1.67, 95% CI 1.10–2.54, P = 0.02).Conclusions:In summary, clopidogrel pretreatment was associated with significantly lower mortality, major adverse cardiovascular events, myocardial infarction and revascularization with no increase in major bleeding. However, these advantages were not observed with prasugrel or ticagrelor pretreatment.  相似文献   
996.
目的 检测MicroRNA-939(miR-939)和性别决定区相关HMG族盒蛋白4(Sry-related HMG box 4,SOX4)在先天性巨结肠(Hirschsprung's disease,HSCR)中的表达水平,评估miR-939在SOX4调控肠神经嵴前体细胞(enteric neural crest c...  相似文献   
997.
改良外剥内扎术结合中药治疗混合痔250例   总被引:1,自引:0,他引:1  
目的观察改良外剥内扎手术结合中药治疗混合痔的临床疗效。方法对250例混合痔患者采用改良外剥内扎手术治疗,外痔少量或部分切除,尽量多剥离,针对有病灶的内痔黏膜予以结扎;术后予太宁栓和消炎痛栓肛塞,痔疾宁溶液熏洗和坐浴,以红油膏、白玉膏、生肌散等中药外敷换药。结果治愈215例,好转35例,无效0例,总有效率为100%。结论本方法操作简单,患者痛苦小,手术后遗症少,值得推广。  相似文献   
998.
目的:经典1型糖尿病(type 1 diabetes mellitus,T1DM)患者由于胰岛β细胞破坏、胰岛素绝对缺乏,需终身依赖外源性胰岛素治疗。中国糖尿病患儿中T1DM约占90%,发病率快速增加且低龄化严重。流行病学研究显示中国患儿平均糖化血红蛋白(glycated haemoglobin,HbA1c)整体偏高、达标率低。良好的血糖管理是糖尿病治疗的重点,维持血糖在目标范围内可阻止或延缓T1DM患者慢性血管并发症。本研究旨在利用扫描式葡萄糖监测系统(flash glucose monitoring system,FGMS)了解湖南省和河南省T1DM患儿的血糖控制情况,分析该群体血糖波动的影响因素。方法:选择2017年8月至2020年8月于两省16所医院内分泌科就诊的T1DM患儿215例,年龄≤14岁,均佩戴FGMS采集血糖数据,分析HbA1c、病程和葡萄糖扫描频率与血糖波动的相关性;根据患儿病程、HbA1c、葡萄糖扫描频率及胰岛素注射方式等因素进行分组比较。结果:HbA1c、病程与平均血糖、血糖标准差、平均血糖波动幅度(mean amplitude of glucose excu...  相似文献   
999.
目的研究选择性头部降温对缺血性脑损伤胎羊纹状体神经元凋亡和星形胶质细胞增殖的影响。方法胎羊于妊娠117~124d时通过双侧颈动脉阻塞30min造成双侧脑缺血损伤,损伤后将胎羊随机分为:损伤组(n=10)、2h低温组(损伤后2h开始亚低温治疗,n=7)和6h低温组(损伤后6h开始亚低温治疗,n=8),另设正常对照组(n=5)。通过冷循环水进行选择性头部降温,取脑组织用免疫组化法检测胎羊纹状体caspase-3(半胱天冬氨酸酶-3),GFAP(胶质纤维酸性蛋白)和PCNA(增殖细胞核抗原)的表达。结果①纹状体神经元凋亡:正常对照组中,caspase-3表达极少(11.00±13.77),损伤组caspase-3免疫阳性细胞为177.70±48.69,明显增加(P=0.000),损伤后2h治疗组(54.14±39.44,P=0.000)和损伤后6h治疗组(122.43±52.36,P=0.017)均能减少caspase-3免疫阳性细胞。②纹状体星形胶质细胞增殖:与正常对照组(163.40±21.98)相比,缺血性脑损伤组的GFAP免疫阳性细胞明显增多(433.25±66.69,P=0.000),损伤后2h开始亚低温治疗(219.50±35.31,P=0.000)和损伤后6h开始亚低温治疗(272.50±86.20,P=0.000)均能减少GFAP免疫阳性细胞。③纹状体PCNA阳性细胞的表达:在正常对照组中,PCNA免疫阳性细胞较少,为153.40±12.46,缺血性脑损伤组的PCNA免疫阳性细胞明显增多(353.70±45.60,P=0.000),损伤后2h开始亚低温治疗(187.14±26.26,P=0.000)和损伤后6h开始亚低温治疗(230.25±67.46,P=0.000)均能减少PCNA免疫阳性细胞。结论亚低温可以抑制纹状体神经元的凋亡和星形胶质细胞的增殖,该作用可能为选择性头部降温的脑保护作用机制之一。  相似文献   
1000.
背景 抑郁障碍患者的主观认知功能与客观认知功能存在差异。目前,关于主客观认知功能差异影响因素的研究有限。目的 探索抑郁障碍患者主观和客观认知功能的差异及其影响因素,为进一步理解抑郁障碍患者认知功能受损情况提供参考。方法 纳入2022年1月13日—2023年12月11日在成都市第四人民医院门诊就诊或住院治疗的、符合《精神障碍诊断与统计手册(第5版)》(DSM-5)抑郁障碍诊断标准的77例患者为研究对象。采用蒙哥马利-艾森贝格抑郁量表(MADRS)评定患者抑郁症状严重程度,采用抑郁感知缺陷问卷(PDQ-D)和中国简版神经认知成套测验(C-BCT)分别评定患者的主观认知功能和客观认知功能,采用席汉残疾量表(SDS)评定患者的社会功能,以临床总体印象量表-疾病严重程度量表(CGI-SI)评定患者病情严重程度。采用Pearson相关分析考查年龄、受教育年限、MADRS总评分、SDS总评分、CGI-SI评分与主客观认知功能及其差异的相关性。采用多元线性回归探索主客观认知功能差异的影响因素。结果 是否用药的抑郁障碍患者PDQ-D总评分和主客观认知功能差异(D值)比较差异均有统计学意义(t=-4.2...  相似文献   
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