Background: Pulmonary Langerhans cell histiocytosis (PLCH) is an interstitial primary pulmonary disease, characterized by Langerhans cell proliferation. It is easily misdiagnosed in children. This study aimed to ch...Background: Pulmonary Langerhans cell histiocytosis (PLCH) is an interstitial primary pulmonary disease, characterized by Langerhans cell proliferation. It is easily misdiagnosed in children. This study aimed to characterize the clinical manifestations and features of PLCH by retrospective analysis. Meihods: A retrospective analysis was performed in 117 PLCH patients out of 338 LCH patients who were admitted in our center from November 2006 to October 2013. Variables between two groups were compared by Mann-Whitney U-test and Chi-square test. Kaplan-Meier curves were constructed to compare the survival rates and Cox regression to evaluate the effect of risk factors. Results: The median age of PLCH group was significantly lower than that ofnon-PkCH group ( 18.63 months vs. 43.4 months, P 〈 0.001 ). All PLCH children had other organ involvement and only 11 cases (9.4%) had respiratory symptoms. The most common radiologic finding was cystic lesions (29 cases, 24.8%). Pulmonary thnction abnormalities were dominated by obstructive ventilatory dysfunction (63 cases, 82.9%). The 5-year overall survival (OS) of PECH children was 93.6% ± 2.3% and the event-free survival (EFS) was 55.7% ± 5.2%. Among the 38 cases with progressed or relapsed disease, five cases (13.2%) were due to progression or recurrence of lung damage. The 5-year OS of PECH children with "risk organ" involvement was significantly lower than those without "risk organ" involvement (86.0% ± 4.9% vs. 100%,X^2 = 8.793, P= 0.003). The difference of EFS between two groups was also significant (43.7% ± 7.7% vs. 66.3% ± 6.5%,X^2 = 5.399, P = 0.020). The "'risk organ" involvement had a significant impact on survival (hazard ratio = 1.9, P = 0.039). Conclusions: PLCH mainly occurs in young children, and only a small percentage of patients have respiratory symptoms. They generally have other organ involvement. Most of PLCH children have a good prognosis and most lung lesions could have improved展开更多
To study the applicability of biodiesel in marine engines,this research investigated the performance,combustion characteristics,and emission characteristics of biodiesel(B100),diesel,and a 50%volume blend of the two f...To study the applicability of biodiesel in marine engines,this research investigated the performance,combustion characteristics,and emission characteristics of biodiesel(B100),diesel,and a 50%volume blend of the two fuels(B50)in a marine engine.This study was conducted on a 4-cylinder,520 mm-bore,two-stroke,low-speed marine engine with a common rail fuel and exhaust gas charge system.The three fuels were tested at different loads from 25%–100%with a step size of 25%.Results showed that the fuel consumption of pure biodiesel increased by about 13.5%and 3.8%relative to that of diesel at 25%and 100%loads,respectively,and by about 6%at 50%and 75%loads.In-cylinder combustion pressure was slightly reduced when the engine ran on biofuel,and black carbon emissions from biodiesel were reduced by an average of 54.7%.Compared with those from diesel,the carbon CO and total hydrocarbon emissions from B100 were reduced by 11.3%and 39%,respectively.Nitroxide emissions were elevated for B100 and B50 under all loading conditions.The properties of B50 blended diesel lie between those of B100 and diesel.In terms of combustion characteristics and emissions,biodiesel can be used without changing the engine parameters and can effectively reduce pollution,such as black carbon and carbon monoxide.展开更多
综合标准化是保障产品标准化整体协调一致的重要方法。在电力系统建设运行中开展综合标准化有利于保证整个生产过程的规范性。本文选取智能变电站继电保护及自动化系统为综合标准化研究对象,围绕智能变电站继电保护设备、二次回路、自...综合标准化是保障产品标准化整体协调一致的重要方法。在电力系统建设运行中开展综合标准化有利于保证整个生产过程的规范性。本文选取智能变电站继电保护及自动化系统为综合标准化研究对象,围绕智能变电站继电保护设备、二次回路、自动化系统等进行核心要素分析,建立了包含装置本体、设计、施工、检验、运维等方面的标准综合体,并在500 k V溧阳智能变电站中进行应用。展开更多
基金This study was supported by grants from the National Science and Technology Key Projects (No. 2017ZX09304029004), Beijing Municipal Science and Technology Commission (No. ZI71100001017050), National Natural Science Foundation of China (No. 81700186), Scientific Research Common Program of Beijing Municipal Commission of Education (No. KM201710025019), Pediatric Project of Ai You Foundation (No. AYEK201802), and Talent Training Project-Fostering Fund of National Natural Science Foundation of Beijing Children's Hospital, Capital Medical University (No. GPY201713).
文摘Background: Pulmonary Langerhans cell histiocytosis (PLCH) is an interstitial primary pulmonary disease, characterized by Langerhans cell proliferation. It is easily misdiagnosed in children. This study aimed to characterize the clinical manifestations and features of PLCH by retrospective analysis. Meihods: A retrospective analysis was performed in 117 PLCH patients out of 338 LCH patients who were admitted in our center from November 2006 to October 2013. Variables between two groups were compared by Mann-Whitney U-test and Chi-square test. Kaplan-Meier curves were constructed to compare the survival rates and Cox regression to evaluate the effect of risk factors. Results: The median age of PLCH group was significantly lower than that ofnon-PkCH group ( 18.63 months vs. 43.4 months, P 〈 0.001 ). All PLCH children had other organ involvement and only 11 cases (9.4%) had respiratory symptoms. The most common radiologic finding was cystic lesions (29 cases, 24.8%). Pulmonary thnction abnormalities were dominated by obstructive ventilatory dysfunction (63 cases, 82.9%). The 5-year overall survival (OS) of PECH children was 93.6% ± 2.3% and the event-free survival (EFS) was 55.7% ± 5.2%. Among the 38 cases with progressed or relapsed disease, five cases (13.2%) were due to progression or recurrence of lung damage. The 5-year OS of PECH children with "risk organ" involvement was significantly lower than those without "risk organ" involvement (86.0% ± 4.9% vs. 100%,X^2 = 8.793, P= 0.003). The difference of EFS between two groups was also significant (43.7% ± 7.7% vs. 66.3% ± 6.5%,X^2 = 5.399, P = 0.020). The "'risk organ" involvement had a significant impact on survival (hazard ratio = 1.9, P = 0.039). Conclusions: PLCH mainly occurs in young children, and only a small percentage of patients have respiratory symptoms. They generally have other organ involvement. Most of PLCH children have a good prognosis and most lung lesions could have improved
基金Ministry of Industry and Information Technology High-tech Ship Research Project(Grant No.MC-202019-C08)Shanghai Ship Intelligent Operation and Maintenance and Energy Efficiency Monitoring Engineering Technology Research Center,Shanghai Science and Technology Program(Grant No.20DZ2252300).
文摘To study the applicability of biodiesel in marine engines,this research investigated the performance,combustion characteristics,and emission characteristics of biodiesel(B100),diesel,and a 50%volume blend of the two fuels(B50)in a marine engine.This study was conducted on a 4-cylinder,520 mm-bore,two-stroke,low-speed marine engine with a common rail fuel and exhaust gas charge system.The three fuels were tested at different loads from 25%–100%with a step size of 25%.Results showed that the fuel consumption of pure biodiesel increased by about 13.5%and 3.8%relative to that of diesel at 25%and 100%loads,respectively,and by about 6%at 50%and 75%loads.In-cylinder combustion pressure was slightly reduced when the engine ran on biofuel,and black carbon emissions from biodiesel were reduced by an average of 54.7%.Compared with those from diesel,the carbon CO and total hydrocarbon emissions from B100 were reduced by 11.3%and 39%,respectively.Nitroxide emissions were elevated for B100 and B50 under all loading conditions.The properties of B50 blended diesel lie between those of B100 and diesel.In terms of combustion characteristics and emissions,biodiesel can be used without changing the engine parameters and can effectively reduce pollution,such as black carbon and carbon monoxide.
文摘综合标准化是保障产品标准化整体协调一致的重要方法。在电力系统建设运行中开展综合标准化有利于保证整个生产过程的规范性。本文选取智能变电站继电保护及自动化系统为综合标准化研究对象,围绕智能变电站继电保护设备、二次回路、自动化系统等进行核心要素分析,建立了包含装置本体、设计、施工、检验、运维等方面的标准综合体,并在500 k V溧阳智能变电站中进行应用。