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Evaluation of Interferon-Gamma Release Assay Testing and Tuberculin Skin Test for Early Diagnosis of Tuberculosis in Children and Adolescents
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作者 Yelda Sorguç Miray Çelebi Yılmaz +4 位作者 Yüce Ayhan Yakup Yaman Şener Tulumoğlu Aybüke Akaslan Kara İlker Devrim 《Open Journal of Pediatrics》 2024年第3期558-567,共10页
Background: This study aimed to evaluate the diagnostic value of interferon-γ release assay (IGRA), a sensitive microbiological diagnostic method, in children and adolescents with suspected tuberculosis in a country ... Background: This study aimed to evaluate the diagnostic value of interferon-γ release assay (IGRA), a sensitive microbiological diagnostic method, in children and adolescents with suspected tuberculosis in a country with a high burden of tuberculosis. Method: This study included 581 children and adolescents aged 4 - 19 years who were suspected of having tuberculosis, were latently infected with Mycobacterium tuberculosis, and had received at least one dose of BCG vaccine between April 17, 2019, and February 24, 2021. The study evaluated the TST results of 106 patients who had a positive Quantiferon test and were suspected of having tuberculosis. Results: The study included 581 patients aged between 4 and 19 years. Of these, 106 patients tested positive for the Quantiferon test, while 19 were indeterminate and 456 were negative. The Quantiferon test positivity rate was 18.24%. Among the 106 QFT-Plus-positive cases, 23 patients also tested positive for TST. The difference in distribution was found to be statistically significant. Conclusion: The QFT-Plus test is considered an alternative to TST and other microbiological diagnostic methods for early tuberculosis diagnosis, particularly in children and adolescents. 展开更多
关键词 Interferon Gamma release Assay CHILDREN Tuberculin test CHILDREN Latent Tuberculosis
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Assessing the energy release characteristics during the middle detonation reaction stage of aluminized explosives
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作者 Kun Yang Lang Chen +3 位作者 Danyang Liu Bin Zhang Jianying Lu Junying Wu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期270-277,共8页
Afterburning behind the detonation front of an aluminized explosive releases energy on the millisecond timescale,which prolong the release of detonation energy and the energy release at different stages also shows sig... Afterburning behind the detonation front of an aluminized explosive releases energy on the millisecond timescale,which prolong the release of detonation energy and the energy release at different stages also shows significant differences.However,at present,there are few effective methods for evaluating the energy release characteristics of the middle reaction stage of such explosives,which can have a duration of tens to hundreds of microseconds.The present work demonstrates an approach to assessing the midstage of an aluminized explosive detonation based on a water push test employing a high degree of confinement.In this method,the explosive is contained in a steel cylinder having one end closed that is installed at the bottom of a transparent water tank.Upon detonation,the gaseous products expand in one direction while forcing water ahead of them.The resulting underwater shock wave and the interface between the gas phase products and the water are tracked using an ultra-high-speed framing and streak camera.The shock wave velocity in water and the expansion work performed by the gaseous detonation products were calculated to assess the energy release characteristics of aluminized explosives such as CL-20 and RDX in the middle stage of the detonation reaction.During the middle stage of the detonation process of these aluminized explosives,the aluminum reaction reduced the attenuation of shock waves and increased the work performed by gas phase products.A higher aluminum content increased the energy output while the presence of oxidants slowed the energy release rate.This work demonstrates an effective means of evaluating the performance of aluminized explosives. 展开更多
关键词 Aluminized explosive Non-ideal detonation Water push test Energy release
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Long-release-interval-first real-time scheduling algorithm and its schedulability test
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作者 沈卓炜 汪芸 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期484-489,共6页
To fulfill the requirements for hybrid real-time system scheduling, a long-release-interval-first (LRIF) real-time scheduling algorithm is proposed. The algorithm adopts both the fixed priority and the dynamic prior... To fulfill the requirements for hybrid real-time system scheduling, a long-release-interval-first (LRIF) real-time scheduling algorithm is proposed. The algorithm adopts both the fixed priority and the dynamic priority to assign priorities for tasks. By assigning higher priorities to the aperiodic soft real-time jobs with longer release intervals, it guarantees the executions for periodic hard real-time tasks and further probabilistically guarantees the executions for aperiodic soft real-time tasks. The schedulability test approach for the LRIF algorithm is presented. The implementation issues of the LRIF algorithm are also discussed. Simulation result shows that LRIF obtains better schedulable performance than the maximum urgency first (MUF) algorithm, the earliest deadline first (EDF) algorithm and EDF for hybrid tasks. LRIF has great capability to schedule both periodic hard real-time and aperiodic soft real-time tasks. 展开更多
关键词 real-time scheduling schedulability test earliest deadline first maximum urgency first long release interval first
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Release test of alliin/alliinase double-layer tablet by HPLC-Allicin determination 被引量:3
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作者 Yan Liang Jing-Jing Zhang +5 位作者 Qi-Bing Zhang Zhong-Xia Wang Zong-Ning Yin Xin-Xia Li Jian Chen Li-Ming Ye 《Journal of Pharmaceutical Analysis》 SCIE CAS 2013年第3期187-192,共6页
A simple, precise and accurate method was developed and validated for the determination of allicin release from alliin/alliinase double-layer tablets. According to Appendix XC Ⅱ of Chinese Pharmacopoeia 2010 edition ... A simple, precise and accurate method was developed and validated for the determination of allicin release from alliin/alliinase double-layer tablets. According to Appendix XC Ⅱ of Chinese Pharmacopoeia 2010 edition Volume II, a small glass-method was adopted at the rotational speed of 100 r/min using 100 mL phosphate buffer (pH 6.8) as release medium. The release amount was determined by HPLC with a C18 column (250 mm × 4.6 mm, 5 μm) using the mobile phase consisting of methanol -0.4% carboxylic acid (65:35) at a flow rate of 1 mL/min and UV detection at 242 nm. The current method demonstrates good linearity over the range 4.052- 405.2 μg/mL (r2=0.9999) with an average recovery of 105.5%(RSD= 1.25%). The accumulative release of alliin/alliinase double-layer tablets had good homogeneity for withinand betweenbatches. The method established is simple, accurate and repeatable for the determination of allicin release from alliin/alliinase double-layer tablets. 展开更多
关键词 Alliin/alliinase Double-layer tablet ALLICIN release test HPLC
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Performance and correlation of interferon gamma release assays and tuberculin skin test in HIV-infected children and adolescents with immune reconstitution 被引量:2
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作者 Keswadee Lapphra Rati Diwitaya +9 位作者 Sansnee Senawong Maneeprang Thovarabha Parnwas Pinnobphun Alan Maleesatharn Nantaka Kongstan Benjawan Khumcha Wanatpreeya Phongsamart Orasri Wittawatmongkol Supattra Rungmaitree Kulkanya Chokephaibulkit 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2020年第10期464-466,共3页
Objective:To evaluate the performance of interferon gamma release assays and tuberculin skin test in HIV-infected children and adolescents with immune reconstitution.Methods:A cross-sectional study was conducted in HI... Objective:To evaluate the performance of interferon gamma release assays and tuberculin skin test in HIV-infected children and adolescents with immune reconstitution.Methods:A cross-sectional study was conducted in HIV-infected patients aged 5-18 years receiving antiretroviral treatment with CD4 T-lymphocytes>25%or>500 cells/mm3 for at least 6 months.QuantiF ERON-TB Gold,T-SPOT.TB,and tuberculin skin test were performed in each patient.Results:A total of 50 patients were enrolled with median age of 13.7 years,CD4 counts of 753(IQR:587-989)cells/mm3.Among 27 patients with tuberculosis(16)or tuberculosis exposure(11),8(29.6%)were positive to at least one test,2(7.4%)were positive QuantiFERON-TB Gold,3(11.1%)positive T-SPOT.TB,and 7(25.9%)had tuberculin skin test≥5 mm.Among 23 patients without history of tuberculosis or exposure,all had negative interferon gamma release assays,while 2(8.7%)had positive tuberculin skin test.Conclusions:All tests had low sensitivity despite immune reconstitution. 展开更多
关键词 CHILDREN HIV TB Interferon gamma release assays Tuberculin skin test
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Study on the Rapid Method to Predict Longevity of Controlled Release Fertilizer Coated by Water Soluble Resin 被引量:10
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作者 DAI Jian-jun FAN Xiao-lin +2 位作者 YU Jian-gang LIU Fang ZHANG Qiao 《Agricultural Sciences in China》 CAS CSCD 2008年第9期1127-1132,共6页
The study discussed the rapid method to test and predict the longevity of controlled release fertilizers (CRFs) coated by water soluble resin by using the short-term leaching under higher temperature. Pure water dis... The study discussed the rapid method to test and predict the longevity of controlled release fertilizers (CRFs) coated by water soluble resin by using the short-term leaching under higher temperature. Pure water dissolving incubation and higher temperature leaching were used to study the patterns of the nutrient release of the CRFs. The correlation analysis between the days at 25℃ and the hours at 80℃ of Trincote 1 and Trincote 2 for the same cumulative release rates were conducted. Patterns of cumulative nutrient release curve followed one factor quadratic regression equation at each given temperatures, and each of relative coefficient was bigger than 0.995. As the temperature increased, nutrients release of the CRFs increased. The longevity of resin coated CRFs were predicted by use of both the cumulative nutrients release equation at 80℃ and the regression equation of release time needed for the same cumulative release rates between 25 and 80℃. There were only 0.3-6.9% relative errors between the tested longevity and predicted one. In conclusion, the longevity of resin coated CRFs could be predicted more quickly and precisely by use of the higher temperature short-term leaching method than that of the traditional differential release rate. The longevity of resin coated CRF could be rapidly and precisely predicted in a few hours by application of the higher temperature shortterm leaching method. 展开更多
关键词 controlled release fertilizer (CRF) water soluble resin coating longevity of CRF rapid test method
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Monolithic LC method applied to fesoterodine fumarate low dose extended-release tablets:Dissolution and release kinetics 被引量:2
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作者 Maximiliano S.Sangoi Vítor Todeschini Martin Steppe 《Journal of Pharmaceutical Analysis》 CAS 2015年第2期137-141,共5页
A dissolution test for fesoterodine low dose extended-release tablets using liquid chromatographic(LC) method equipped with a C18 monolithic column was developed and validated. LC system was operated isocratically a... A dissolution test for fesoterodine low dose extended-release tablets using liquid chromatographic(LC) method equipped with a C18 monolithic column was developed and validated. LC system was operated isocratically at controlled temperature(40 1C) using a mobile phase of acetonitrile:methanol:0.03 M ammonium acetate(p H 3.8)(30:15:55, v/v/v), run at a flow rate of 1.5 m L/min and detected at 208 nm. The best dissolution conditions for this formulation were achieved using a USP apparatus 2(paddle) at 100 rpm and 900 m L of phosphate buffer at p H 6.8 as the dissolution medium.Validation parameters such as the specificity, linearity, accuracy, precision, and robustness were evaluated according to international guidelines, giving results within the acceptable range. The kinetic parameters of drug release were also investigated using model-dependent methods and the dissolution profiles were best described by the Higuchi model. The validated dissolution test can be applied for quality control of this formulation. 展开更多
关键词 FESOTERODINE Dissolution test Low dose extendedrelease tablets Monolithic LC release kinetics
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Oxidative heat release intensity in coal at low temperatures measured by the hot-wire method 被引量:1
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作者 YANG Yong-liang LI Zeng-hua PAN Shang-kun GAO Si-yuan WANG Ya-li 《Mining Science and Technology》 EI CAS 2009年第3期326-330,共5页
Directly measuring the oxidative heat release intensity at low temperatures is difficult at present.We developed a new method based on heat conduction theory that directly measures heat release intensity of loose coal... Directly measuring the oxidative heat release intensity at low temperatures is difficult at present.We developed a new method based on heat conduction theory that directly measures heat release intensity of loose coal at low temperatures.Using this method, we calculated the oxidative heat release intensity of differently sized loose coals by comparing the temperature rise of the coal in nitrogen or an air environment.The results show that oxidation heat release intensity of Shenhua coal sized 0~15 mm is 0.001~0.03 W/m3 at 30~90 °C and increases with increasing temperature.The heat release intensity at a given temperature is larger for smaller sized coal.The temperature effect on heat release intensity is muted as the coal size increases.At lower temperature the change in heat release intensity as a function of size becomes smaller.These results show that the test system is usable for practical applications and is easy to operate and is capable of measuring mass samples. 展开更多
关键词 coal spontaneous combustion oxidation heat release intensity of coal test system DIAMETER
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Energy Release Rate Measurement of Welded Bamboo Joints
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作者 Haiyang Zhang Qian He +3 位作者 Xiaoning Lu A.Pizzi Changtong Mei Xianxu Zhan 《Journal of Renewable Materials》 SCIE 2018年第5期450-456,共7页
Double cantilever beam tests were used to measure the energy release rates of linear vibrational welded moso bamboo joints.The influence of the length of the preserved cracks,the different combinations of the inner an... Double cantilever beam tests were used to measure the energy release rates of linear vibrational welded moso bamboo joints.The influence of the length of the preserved cracks,the different combinations of the inner and outer bamboo surfaces and the moisture content is studied herein.The experimental compliance method,which is based on linear elastic fracture mechanics and has been shown to be an ideal method,was used to analyze data with the power equation.The results show that the preserved initial crack length does not have a significant effect on the final measured energy release rate,while the moso bamboo combination does affect the properties dramatically.The welded moso bamboo joints with inner-inner surfaces have the highest energy release rate of 122 J/m^2.The average energy release of the outer-outer combination was only 102 J/m^2.The expansion of the cracks also became easier when the moisture content of the welded joints was 18.5%compared to 4.5% and 10.1%.So the moisture resistance of the welded joints should be duly improved. 展开更多
关键词 Energy release rate welded moso bamboo moisture content DCB test
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Mating behavior and sex pheromone release rhythm of Holotrichia parallela(Coleoptera: Melolonthidae)
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作者 Zhen Yang Dan Liang +6 位作者 Qian Ju Quansen Chen Xiao Li Xiaojing Jiang Maohua Chen Weiqiang Yang Mingjing Qu 《Oil Crop Science》 2019年第1期10-16,共7页
Mating behavior and sex pheromone release rhythm of Holotrichia parallela was studied in this research. The maximum mating times were 3 for female and 4 for male. Average mating times were 1.06 for female and 0.91 for... Mating behavior and sex pheromone release rhythm of Holotrichia parallela was studied in this research. The maximum mating times were 3 for female and 4 for male. Average mating times were 1.06 for female and 0.91 for male. L-isoleucine methyl ester(LIME), a major component of pheromone, increased gradually from 14:00 and peaked at 19:00, then dropped sharply at 20:00 and remained low at 24:00.(R)-(-)-linalool(referred as linalool below) maintained similar levels throughout the study period. Calling and mating activity significantly decreased LIME titer, but not linalool. Analyses of 11 samples collected during calling days(20 d-70 d) revealed that LIME production was affected by female age. LIME titers increased from 20 d to 45 d, and decreased from 45 d to 70 d. While linalool titers remained at similar levels at all sampling dates. The highest ratio between LIME and linalool was 12 and the lowest was 4. Field tests confirmed that the most attractive ratios of LIME: linalool in early season(June 1 to 20) and late season(August 1 to 20) were 6:1, while in the most serious injury stage(June 20 to August 1) was 12:1. This is the first report about circadian rhythmicity of sex pheromone in Holotrichia parallela, which provides a basis for controlling it in field. 展开更多
关键词 PHEROMONE release RHYTHM MATING times PHEROMONE lure field test
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Rationale of Timed-Release Analysis and the Improvement of Flotation Experiment
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作者 刘炯天 周振英 +2 位作者 李备备 沈正义 王进才 《International Journal of Mining Science and Technology》 SCIE EI 1998年第2期113-117,共5页
The fundamental aspects of The Timed-Release Analysis (TRA) and some problems are analysed. Having studied the attribute of optimum flotation test results and the way of optimum test conditions, the auther put forward... The fundamental aspects of The Timed-Release Analysis (TRA) and some problems are analysed. Having studied the attribute of optimum flotation test results and the way of optimum test conditions, the auther put forward a proposal to improve this test method by adding a new test step of scavenging flotation and using optimum test conditions varied with different fine coals instead of the given ones settled by the TRA norm. Comparison between test results of the two methods of TRA shows that the improved method is very good. 展开更多
关键词 laboratory COAL FLOTATION test Method timed-release ANALYSIS optimization of test conditions optimum results of COAL FLOTATION
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地浸砂岩型铀矿松散岩层单动双管取心钻具的研制与试验 被引量:1
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作者 李博 刘晓阳 +2 位作者 王琳 邓氚军 杨爱军 《铀矿地质》 CSCD 2024年第1期181-188,共8页
为解决单管钻具取心工艺方法在深部目的层/矿层等松散岩层取心中存在的取心质量差、取心效率低和操作难度大的问题,开展了地浸砂岩型铀矿松散岩层单动双管钻具的研制和试验。通过设计和改进单动机构、断心结构、液力退心机构和快拆机构... 为解决单管钻具取心工艺方法在深部目的层/矿层等松散岩层取心中存在的取心质量差、取心效率低和操作难度大的问题,开展了地浸砂岩型铀矿松散岩层单动双管钻具的研制和试验。通过设计和改进单动机构、断心结构、液力退心机构和快拆机构,研制了两类分别具有可直接液力退心和快速拆卸功能的SD型单动双管钻具。试验结果表明:SD110型双管钻具可在免拆内管的情况下实现地表快速液力退心,提高双管钻具退心效率;SDKC110型钻具可快速拆装更换内管,实现退心和钻进平行作业。与单管钻具相比,SD系列单动双管钻具在松散岩层的平均回次长度提高28.62%,平均机械钻速提高11.61%;与常规单动双管钻具相比,退心操作时间降低了32.69%。SD系列单动双管钻具适用于在松散破碎地层进行取心钻进应用,可有效提高岩心采取效率和岩心质量。 展开更多
关键词 单动双管钻具 液力退心 快速拆卸 设计与试验
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基于鱼类上溯行为的导鱼堰设计与效果评估
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作者 李广宁 柳松涛 +4 位作者 柳海涛 郑铁刚 石凯 孙双科 刘珺 《农业工程学报》 EI CAS CSCD 北大核心 2024年第7期117-123,共7页
河道内鱼类上溯路径不唯一,聚集位置更是难以预测,对鱼类上溯行为进行有效引导有助于提升过鱼设施进口的效率。为此,该研究提出了一种导鱼堰的概念和设计方法,结合姚家坪水电站的过鱼设施,利用流场三维数值模拟、鱼类洄游(active fish m... 河道内鱼类上溯路径不唯一,聚集位置更是难以预测,对鱼类上溯行为进行有效引导有助于提升过鱼设施进口的效率。为此,该研究提出了一种导鱼堰的概念和设计方法,结合姚家坪水电站的过鱼设施,利用流场三维数值模拟、鱼类洄游(active fish migration,AFM)模型和实鱼试验对导鱼堰的效果进行评估。结果表明:姚家平水利枢纽工程的导鱼堰上下游水面落差为0.36~0.40 m,过堰水流流速可达1.5~2.8 m/s,形成阻鱼的屏障,并在导鱼堰下游侧形成了诱导鱼类向集鱼渠进鱼口游动的唯一低流速上溯通道,鱼类聚集点趋于唯一,验证了导鱼堰方案的合理性。利用鱼类洄游模型对导鱼堰的导鱼效果进行预测,结果表明,下游高水位和低水位2种工况下,90%以上的鱼类游动路径均表现出相似的规律,鱼类沿河道右岸和导鱼堰下游侧的低流速通道上溯,并最终聚集在集鱼渠的进鱼口处。放鱼试验中试验个体全部进入集鱼渠,结果进一步证实导鱼堰可以有效引导鱼类游动路线,并在集鱼渠进鱼口处形成唯一的聚集区。本文提出的导鱼堰丰富了生态水工建筑物的形式,可为过鱼设施进口的水力设计及下游河道的局部整治提供参考。 展开更多
关键词 渔业 数值模拟 过鱼设施 导鱼堰 鱼类洄游模型 实鱼试验
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简化PCOS患者胰岛素释放和糖耐量实验的效果评价
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作者 周红娣 王哲蔚 《生殖医学杂志》 CAS 2024年第3期316-321,共6页
目的研究从检测时间点上简化多囊卵巢综合征(PCOS)患者胰岛素释放和糖耐量实验对评价胰岛素抵抗和糖代谢异常的效果。方法通过回顾性研究,选取2021年8月至2022年8月在我院就诊的320例已完成胰岛素释放和糖耐量试验(临床“金标准”)的PCO... 目的研究从检测时间点上简化多囊卵巢综合征(PCOS)患者胰岛素释放和糖耐量实验对评价胰岛素抵抗和糖代谢异常的效果。方法通过回顾性研究,选取2021年8月至2022年8月在我院就诊的320例已完成胰岛素释放和糖耐量试验(临床“金标准”)的PCOS患者,并假设研究对象只接受了简化方法一“空腹血糖和胰岛素检测”或简化方法二“空腹+糖负荷后2 h血糖和胰岛素检测”,评价两种简化方法的敏感度与临床“金标准”的一致性。结果患者总异常(即胰岛素抵抗或糖代谢异常)的发生率为80.0%(256/320),其中,超重/肥胖的患者和体重正常患者的总异常发生率分别为97.5%(115/118)和69.8%(141/202)。对于总异常的检测,超重/肥胖患者中简化方法一和简化方法二的敏感度分别为93.0%和96.5%(后者一致性检验Kappa=0.585);体重正常患者中,两种简化方法的敏感度分别为58.2%和74.5%。对于“糖代谢异常”的检测,超重/肥胖患者中,两种简化方法的敏感度分别为16.7%和100%(后者一致性检验Kappa=1.000)。结论对所有的PCOS患者均应进行胰岛素抵抗和糖代谢异常的检测;对于超重/肥胖PCOS患者,空腹+糖负荷后2 h血糖和胰岛素检测可以代替胰岛素释放和糖耐量实验;对于体重正常的PCOS患者,二种简化方法均有漏诊风险。 展开更多
关键词 多囊卵巢综合征:胰岛素抵抗 胰岛素释放实验 糖耐量实验
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单时相GnRH激发试验对不同体重指数女童中枢性性早熟诊断价值的研究
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作者 王伟 王一凡 +4 位作者 肖雅 张红如 孙俊 史文慧 李锦波 《中国当代儿科杂志》 CAS CSCD 北大核心 2024年第6期592-598,共7页
目的 探讨单时相促性腺激素释放激素(gonadotropin-releasing hormone,GnRH)激发试验对不同体重指数(body mass index,BMI)女童中枢性性早熟(central precocious puberty,CPP)的诊断价值。方法 回顾性分析2017年1月—2023年8月在郑州大... 目的 探讨单时相促性腺激素释放激素(gonadotropin-releasing hormone,GnRH)激发试验对不同体重指数(body mass index,BMI)女童中枢性性早熟(central precocious puberty,CPP)的诊断价值。方法 回顾性分析2017年1月—2023年8月在郑州大学第三附属医院就诊的7.5岁前出现乳房发育的760例女童数据。根据GnRH激发试验结果和临床表现综合诊断,分为CPP组(n=297)和非CPP组(n=463)。再根据体重指数(body mass index,BMI)分为正常体重组(n=540)、超重组(n=116)及肥胖组(n=104)。采用受试者操作特征曲线分析单时相GnRH激发试验对不同BMI女童CPP的诊断价值。结果 GnRH激发后30 min黄体生成素(luteinizing hormone,LH)/卵泡刺激素诊断CPP的曲线下面积为0.985,高于0、60、90 min LH/卵泡刺激素的曲线下面积(P<0.05)。30 min与60 minLH诊断价值相当(P>0.05)。30 min LH与BMI及BMI-Z值呈负相关(P<0.05)。30 min LH在正常体重、超重、肥胖女童中诊断CPP的曲线下面积分别为0.952、0.965、0.954 (P<0.05)。结论 30 min GnRH激发试验对不同BMI女童CPP均有较好的诊断价值,有望替代传统的GnRH激发试验,但应注意BMI对LH水平的影响。 展开更多
关键词 中枢性性早熟 体重指数 黄体生成素 促性腺激素释放激素激发试验 女童
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基于深度学习的隧道火灾火源位置和热释放速率反演
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作者 蒋立 何廷全 +1 位作者 郭鑫 阳东 《消防科学与技术》 CAS 北大核心 2024年第9期1292-1297,1315,共7页
火源位置和热释放速率(HRR)是指导隧道火灾消防应急救援的重要信息。但在实际中,得到的关于火场的信息十分有限,很难直接得到火源关键信息。提出了一种基于深度学习的隧道火灾火源位置和HRR的反演方法。首先,基于试验数据验证的数值模... 火源位置和热释放速率(HRR)是指导隧道火灾消防应急救援的重要信息。但在实际中,得到的关于火场的信息十分有限,很难直接得到火源关键信息。提出了一种基于深度学习的隧道火灾火源位置和HRR的反演方法。首先,基于试验数据验证的数值模拟建立不同边界条件下的隧道火灾数据集。基于卷积神经网络(CNN)和长短期记忆网络(LSTM)建立有限的固定式传感器温度数据和火源位置及HRR之间的映射关系,评估了该模型对于火源位置和HRR的反演效果。评估了时间输入步长和传感器间距对该模型反演性能的影响。结果表明,该模型对HRR和火源位置都有较好的反演性能,当时间输入步长为20 s,传感器间距为30 m时,模型反演HRR和火源位置的R2值分别为0.97和0.99。 展开更多
关键词 隧道火灾 数值模拟 火灾试验 长短期记忆网络 热释放速率 深度学习
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凯巴萨水电站泄水建筑物模型试验研究
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作者 田静 郭汉驰 薛海 《水电与新能源》 2024年第10期22-25,共4页
基于大比尺水工模型试验,分析安哥拉凯巴萨水电站表孔泄洪、底孔泄洪及表底联合泄洪时不同运行工况下流态、流速、闸门允许开启高度等水力特性,研究表明泄水建筑物体型及布置总体合理。高水位大流量泄洪时溢流表孔闸后横向扩散水流在挑... 基于大比尺水工模型试验,分析安哥拉凯巴萨水电站表孔泄洪、底孔泄洪及表底联合泄洪时不同运行工况下流态、流速、闸门允许开启高度等水力特性,研究表明泄水建筑物体型及布置总体合理。高水位大流量泄洪时溢流表孔闸后横向扩散水流在挑坎鼻坎附近碰撞激起高的掺气水冠,溢流坝闸门相对开度e/H<0.57,此时闸前水流水力条件较优,溢流坝掺气坎掺气效果较佳;若遇设计洪水,优选5个表孔闸门全开敞泄洪水。本研究成果可供类似工程设计及泄水建筑物调度决策参考。 展开更多
关键词 泄水建筑物 水力特性 模型试验 闸门开度 优化调度
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中西医诊治儿童性早熟研究进展
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作者 章淼滢 孙艳艳 +1 位作者 孙雯 俞建 《河南中医》 2024年第4期621-627,共7页
目前,越来越多的无创诊断技术正在运用到儿童性早熟的诊断中,基因检测技术促进了该病遗传病因诊断的发展。对于该病的治疗,西医主要通过病因治疗继发性性早熟,对于特发性外周性性早熟没有特殊治疗方案,目前,中枢性性早熟治疗首选促性腺... 目前,越来越多的无创诊断技术正在运用到儿童性早熟的诊断中,基因检测技术促进了该病遗传病因诊断的发展。对于该病的治疗,西医主要通过病因治疗继发性性早熟,对于特发性外周性性早熟没有特殊治疗方案,目前,中枢性性早熟治疗首选促性腺激素释放激素类似物(gonadotropin-releasing hormone agonist, GnRHa)。中医认为,性早熟病机为阴虚火旺,肝郁化火,痰湿壅滞,治以滋阴降火、疏肝解郁或燥湿化痰,可改善症状,抑制骨龄快速增长。但目前中医药治疗性早熟的临床研究证据等级不高,缺少样本量大、严格且全面的临床研究,未来可通过开展多中心的随机对照、大样本研究以验证中医药治疗性早熟的疗效。网络药理学和中药成分动物实验研究证明了中药治疗性早熟的部分机制,但中药方剂成分复杂,多通过胃肠道吸收后起效,是否可以调节肠道菌群、产生特异性菌群,该菌群是否改变了机体中某些代谢产物水平从而发挥治疗作用尚无相关研究,今后可开展更多的相关机制研究。 展开更多
关键词 儿童性早熟 基因检测技术 促性腺激素释放激素类似物 阴虚火旺证 肝郁化火证 痰湿壅滞证
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高压电缆接头防爆保护装置的泄能孔优化设计方法 被引量:1
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作者 雷佳成 杨鑫 +3 位作者 秦睿 仇炜 董盼 蒋凌峰 《电工电能新技术》 CSCD 北大核心 2024年第3期83-92,共10页
金属型高压防爆保护装置的泄能孔设计是实现其防爆功能的关键。本文提出了金属型高压电缆接头防爆保护装置泄能孔的设计原则和优化方法;通过热源等效和基于多物理场耦合的有限元计算方法,对保护装置内部发生短路电弧的爆炸时装置内部冲... 金属型高压防爆保护装置的泄能孔设计是实现其防爆功能的关键。本文提出了金属型高压电缆接头防爆保护装置泄能孔的设计原则和优化方法;通过热源等效和基于多物理场耦合的有限元计算方法,对保护装置内部发生短路电弧的爆炸时装置内部冲击过程进行仿真计算,并通过燃弧试验验证了仿真方法的准确性和可靠性。通过仿真计算出封闭设备泄压面积计算公式的关键参数,得到泄能孔开口尺寸的阈值;仿真了装置内部短路电弧爆炸时最大气压出现时刻以及该时刻下不同泄能孔尺寸所对应的保护装置内壁上的压强分布,得到保护装置内部最大压强与泄能孔开口尺寸的函数关系,进而得到保护装置的泄能孔最优开口尺寸。以35 kV电压等级为例,计算得到金属型保护装置的泄能孔尺寸为60 mm。该优化设计方法可为35 kV及以上电压等级的高压电缆接头保护装置的泄能孔设计和制造提供理论基础和设计方法。 展开更多
关键词 高压电缆接头 防爆 泄能孔 仿真设计 燃弧测试
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锂离子电池汽车全尺寸火灾试验研究进展综述 被引量:8
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作者 杨晓菡 张怡 +1 位作者 邓玲 谢元一 《消防科学与技术》 CAS 北大核心 2024年第1期29-33,共5页
分析近年来国内外发生的锂离子电池电动汽车火灾事故,对电动汽车的火灾风险进行简要概括。重点针对美国、加拿大、奥地利、瑞典、中国等国家在锂离子电池电动汽车全尺寸火灾试验及火灾防控方面的科研成果进行综述。根据国内外研究成果,... 分析近年来国内外发生的锂离子电池电动汽车火灾事故,对电动汽车的火灾风险进行简要概括。重点针对美国、加拿大、奥地利、瑞典、中国等国家在锂离子电池电动汽车全尺寸火灾试验及火灾防控方面的科研成果进行综述。根据国内外研究成果,对不同电池容量的锂离子电池电动汽车的热释放速率进行汇总,重点总结燃烧总热释放量、热释放速率峰值和释放有毒氟化氢气体与电池容量的关系。旨在为我国锂离子电池电动汽车火灾防控和火灾风险评估技术研究提供必要的数据参考。 展开更多
关键词 锂离子电池 电动汽车 全尺寸火灾试验 热释放速率
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