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(Dis)Economies of Scale in Business Software Systems Development and Enhancement Projects 被引量:1
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作者 Beata Czamacka-Chrobot 《Computer Technology and Application》 2012年第1期88-97,共10页
In the software engineering literature, it is commonly believed that economies of scale do not occur in case of software Development and Enhancement Projects (D&EP). Their per-unit cost does not decrease but increa... In the software engineering literature, it is commonly believed that economies of scale do not occur in case of software Development and Enhancement Projects (D&EP). Their per-unit cost does not decrease but increase with the growth of such projects product size. Thus this is diseconomies of scale that occur in them. The significance of this phenomenon results from the fact that it is commonly considered to be one of the fundamental objective causes of their low effectiveness. This is of particular significance with regard to Business Software Systems (BSS) D&EP characterized by exceptionally low effectiveness comparing to other software D&EP. Thus the paper aims at answering the following two questions: (1) Do economies of scale really not occur in BSS D&EP? (2) If economies of scale may occur in BSS D&EP, what factors are then promoting them? These issues classify into economics problems of software engineering research and practice. 展开更多
关键词 (dis)economies of scale business software systems development and enhancement projects software size metrics functional size measurement economies of scale factors.
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借助DIS实验突破教学难点——以“磁场对通电导线的作用力”为例
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作者 谭旭艳 吕兵 《实验教学与仪器》 2024年第2期18-19,共2页
教材中直接得出安培力的公式,该知识点难度较大,传统实验现象不够明显且只能定性探究,学生无法真正理解该物理规律和公式。传统实验加DIS实验可对物理规律进行定性和定量的探究,有利于学生物理学科核心素养的培养。
关键词 磁场 通电导线 安培力 dis实验 教学难点
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用DIS电磁定位魔板探究平抛运动的教学设计
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作者 王佳丽 张轶炳 《物理通报》 CAS 2024年第1期90-95,共6页
随着数字化信息系统在中学物理教学中的逐步融入,我国中学物理实验呈现智能化、现代化的发展趋势.以DIS电磁定位魔板为实验装置,通过科学探究的关键环节,设计探究平抛运动的教学流程.实践发现传感器实验也适合做科学探究,能够充分提升... 随着数字化信息系统在中学物理教学中的逐步融入,我国中学物理实验呈现智能化、现代化的发展趋势.以DIS电磁定位魔板为实验装置,通过科学探究的关键环节,设计探究平抛运动的教学流程.实践发现传感器实验也适合做科学探究,能够充分提升学生科学探究和推理论证的能力. 展开更多
关键词 dis电磁定位魔板 平抛运动 科学探究 教学设计
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DIS实验助力高中物理教学探究——以图象问题为例
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作者 刘勇 《中文科技期刊数据库(文摘版)教育》 2024年第8期0156-0159,共4页
实验探究在高中物理教学中扮演着十分重要的角色。在数字化信息系统(DIS)实验的帮助下,弥补了一些传统实验在定量探究上的局限,极大地提升了实验教学效率。这种创新的教学方式有助于培养学生的实验探究精神,让他们养成严谨对待实验结果... 实验探究在高中物理教学中扮演着十分重要的角色。在数字化信息系统(DIS)实验的帮助下,弥补了一些传统实验在定量探究上的局限,极大地提升了实验教学效率。这种创新的教学方式有助于培养学生的实验探究精神,让他们养成严谨对待实验结果并深入剖析数据的科学习惯。本文立足于教学实践,详细探讨了如何有效利用DIS实验助力高中物理教学探究。以"用DIS实验探索力的相互作用、探究向心力实验、验证动量定理的实验案例"为例,展示了DIS实验在课堂中的精准、直观以及实际操作价值。 展开更多
关键词 dis实验 高中物理 教学探究
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基于核心素养的高中物理DIS实验 校本课程开发的实践研究 ——以“探究平抛运动的特点”为例 被引量:1
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作者 黄荣 《中学理科园地》 2024年第1期80-82,86,共4页
运用传感器和计算机技术的DIS实验,兼具精确测量数据和快速直观展示结果的特点,在教育信息化的大背景下,逐渐在高中物理教学中普及。文章以探究平抛运动的特点为例,借助DIS实验的优点进行校本课程的开发,实现对学生核心素养的补充培养... 运用传感器和计算机技术的DIS实验,兼具精确测量数据和快速直观展示结果的特点,在教育信息化的大背景下,逐渐在高中物理教学中普及。文章以探究平抛运动的特点为例,借助DIS实验的优点进行校本课程的开发,实现对学生核心素养的补充培养。通过教学过程中的实践和反思提出了基于学科核心素养应用DIS实验开发校本课程应注意的一些问题。 展开更多
关键词 dis实验 高中物理 平抛运动 核心素养
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The coordinated evolution of ecological environment,public service,and tourism economy along the Silk Road Economic Belt,using the Dual-Carbon Targets
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作者 Shuo Yang Wei Guo +1 位作者 Tianjun Xu Tongtong Liu 《Chinese Journal of Population,Resources and Environment》 2024年第1期34-47,共14页
Carbon peak and carbon neutrality(dual-carbon)are important targets for the international response to climate change.The Silk Road Economic Belt is a strategic resource region and is important for future ecological en... Carbon peak and carbon neutrality(dual-carbon)are important targets for the international response to climate change.The Silk Road Economic Belt is a strategic resource region and is important for future ecological environment and tourism development.Based on the“dual-carbon”targets,the Single index quantification,Multiple index synthesis,and Poly-criteria integration evaluation model were used in this study to measure the coordinated development index of the ecological environment,public service,and tourism economy along the Silk Road Economic Belt and to analyze its spatial and temporal evolution.Further,it explores the dynamic evolution and development trend of the three systems using the Kernel Density and Grey Markov Prediction Model.The results show that the coordinated development index along this region needs to be improved during the study period.Furthermore,the coordinated development index of the Southwest region is relatively higher than that of the Northwest region.From the development trend of the three systems,all of them develop in a stable manner;however,the tourism economy system is easily affected by external disturbances.The coordinated development index of the three systems changes dynamically and tends to be in a good state of coordination.There is a certain spatial and temporal heterogeneity.The gravity center of the coordinated development index has been in the Southwest region.During the forecast period,the coordinated development index along this region will improve significantly,while insufficient and unbalanced development will continue. 展开更多
关键词 Dual-carbon Ecological environment Public services Tourist economy Silk Road economic Belt
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Research on the Digital Economy's Impact on China's Economic Growth:Based on the Variations in Urbanization Levels Across China's Eastern,Central,and Western Regions and Sectoral Heterogeneity
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作者 Qiu Jin Yan Hong 《Contemporary Social Sciences》 2024年第3期27-44,共18页
This paper uses inter-provincial panel data from 2011 to 2017,a linear regression model,and a threshold model to conduct empirical analyses of the impact of the digital economy on China's overall economic growth a... This paper uses inter-provincial panel data from 2011 to 2017,a linear regression model,and a threshold model to conduct empirical analyses of the impact of the digital economy on China's overall economic growth and the three main sectors of industry.The paper then investigates the impact and effects the digital economy has had on the economic growth of the three main sectors of industry in China's eastern,central,and western regions.Finally,the paper investigates the most significant differences among the various regions and the threshold effects of urbanization levels on the relationship between the digital economy and economic growth.The findings indicate a significantly positive correlation between the digital economy and regional economic growth.Moreover,geographical factors notably influence this correlation.The digital economy exerts a positive effect on all sectors of industry.It may not substantially impact industrial development in regions with highly developed infrastructure.Regarding the other regions,the digital economy exhibits varying degrees of impact due to the differences in the specific indicators.The conclusion drawn by the threshold model is that the magnitude of the threshold effect correlates with geographic factors.No threshold effect was observed in the eastern region,while the threshold effect occurred in the central region when the urbanization levels for the provinces were below 0.6645.Similarly,the threshold effect was noted in the western region when the urbanization level was below 0.3931.Considering all of this,the study also offers policy recommendations that will help balance the regional development of digital economies,accelerate the digital transformation of traditional industries,enhance digital infrastructure construction,refine the formulation and implementation of data policy,and establish relevant incentive mechanisms. 展开更多
关键词 digital economy economic growth regional differences urbanization level threshold models
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First results of CO_(2) dispersion interferometer on EAST tokamak
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作者 刘郁阳 李维明 +7 位作者 姚远 张耀 张家敏 连辉 洪博 王守信 揭银先 刘海庆 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期76-82,共7页
A dispersion interferometer(DI)has been installed and operates on the Experimental Advanced Superconducting Tokamak(EAST).This DI system utilizes a continuous-wave 9.3μm CO_(2)laser source to measure line-averaged el... A dispersion interferometer(DI)has been installed and operates on the Experimental Advanced Superconducting Tokamak(EAST).This DI system utilizes a continuous-wave 9.3μm CO_(2)laser source to measure line-averaged electron densities accurately.In contrast to conventional interferometers,the DI does not require substantial vibration isolations or compensating systems to reduce the impact of vibrations in the optical path.It also employs a ratio of modulation amplitudes,ensuring it remains immune to the variations in detected intensities.Without a variation compensation system,the DI system on EAST reaches a density resolution of less than1.8×10^(-2)πrad and a temporal resolution of 20μs.The measurements made by the POlarimeterINTerferometer(POINT)system and the far-infrared hydrogen cyanide(HCN)interferometer are remarkably consistent with the DI’s results.The possibility of fringe jumps and the impact of refraction in high-density discharge can be significantly decreased using a shorter wavelength laser source.A rapid density change of 3×10^(19)m^(-3)during 0.15 s has been measured accurately in shot No.114755 of EAST.Additionally,the DI system demonstrates dependability and stability under 305 s long-pulse discharges in shot No.122054. 展开更多
关键词 dispersion interferometer(di) electron density plasma diagnostics Experimental Advanced Superconducting Tokamak(EAST)
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Digitalization’s Effects on Income Growth and Distribution-Evidence from the CHDES Database
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作者 Huang Yanghua Zhang Jiajia +1 位作者 Cai Yuhan Zhang Jinshuo 《China Economist》 2024年第4期37-56,共20页
Using the CHDES database,we created the CIDI to comprehensively quantify digital adoption at the individual level and examine digitalization’s impact on individual income.Empirical analysis results indicate that incr... Using the CHDES database,we created the CIDI to comprehensively quantify digital adoption at the individual level and examine digitalization’s impact on individual income.Empirical analysis results indicate that increasing the CIDI by one standard deviation(0.13)improves individual income by 5.93 percentage points,which remains true after a series of endogeneity and robustness tests.In the heterogeneity analysis,we discovered that when digital adoption grows,residents in the countryside and county seats can earn more money through internet business operations and other channels.This helps to decrease the urban-rural income divide,but it has also pushed those digitally skilled into high-paying sectors,widening the income gaps between sectors.In the mechanism analysis,we developed an income function that takes into account the individual level of digitalization to show that digitalization can boost income by increasing working hours or labor participation and adjusting the portfolio of individual material,human,and social capital.In this paper,we have expanded the system for measuring the individual levels of digitalization by offering basic data,research methodology,and policy suggestions for the digital economy’s inclusive development. 展开更多
关键词 digital economy level of digitalization digital empowerment income function
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基于学程包和DIS实验提升教学有效性——以“再探NaOH溶液与CO_(2)的反应”为例
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作者 谢志雄 《实验教学与仪器》 2024年第2期26-29,共4页
随着时代发展,信息技术与教学的深度融合趋势越来越明显。以“再探NaOH溶液与CO_(2)反应”为例,利用学程包软件模拟装置搭建,推送习题并反馈答题数据,利用DIS实验精准测出压强的变化数据,帮助学生更好地理解实验原理,从反应物消耗和生... 随着时代发展,信息技术与教学的深度融合趋势越来越明显。以“再探NaOH溶液与CO_(2)反应”为例,利用学程包软件模拟装置搭建,推送习题并反馈答题数据,利用DIS实验精准测出压强的变化数据,帮助学生更好地理解实验原理,从反应物消耗和生成物增加两个角度证明发生了反应。 展开更多
关键词 学程包 dis 信息技术 NAOH CO_(2)
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借助DIS传感器验证实验系统误差的理论分析结果--以“伏安法测量电源电动势和内阻”为例
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作者 张嘉弘 《物理教学探讨》 2024年第6期57-61,共5页
基于“伏安法测量电源电动势和内阻”实验教学中系统误差问题,运用“等效替代”和“微量放大”两种物理思想设计验证性实验,利用DIS传感器与传统实验器材的优化组合,通过数据采集、图像拟合、对比分析,对用伏安法测量产生实验系统误差... 基于“伏安法测量电源电动势和内阻”实验教学中系统误差问题,运用“等效替代”和“微量放大”两种物理思想设计验证性实验,利用DIS传感器与传统实验器材的优化组合,通过数据采集、图像拟合、对比分析,对用伏安法测量产生实验系统误差的理论分析结果进行实验验证。 展开更多
关键词 dis传感器 系统误差 伏安法
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高中物理DIS定量创新实验教学与传统实验教学的比较研究——以“电磁感应定律”为例
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作者 张琅钰 《物理教学探讨》 2024年第2期86-89,共4页
以“电磁感应定律”为例,开发了DIS定量创新实验,以该实验为基础设计了对应的教案,并与传统定性探究实验教学进行对比,发现相比传统定性探究实验教学而言,DIS定量创新实验教学在一定程度上更有利于科学探究的培养。
关键词 物理核心素养 dis定量创新实验 传统定性实验
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基于DIS对影响电流做功的因素实验改进
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作者 刘涛 丁海燕 《中学物理》 2024年第16期61-63,共3页
电功是初中物理教学的难点,教材中直接给出电功定义及公式,然后通过实验验证,不利于学生认知和掌握.实验通过自制教具和利用DIS系统定量探究电功与电压、电流和时间的关系,进一步得出电功公式.
关键词 dis实验 电功 实验改进
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巧用DIS,创新小学科学实验教学——以《比较相同距离内运动的快慢》为例
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作者 纪艺璄 《福建教育》 2024年第6期58-60,共3页
传统科学实验受到实验本身的特性和学生能力的制约,导致学生的探究活动无法全面、合理地进行。教师可以依托数字信息系统,利用实验数据直观呈现实验结果,创新小学科学实验教学,有效提升学生的科学素养。
关键词 dis 科学实验教学 创新
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基于DIS验证变力作用下的动量定理实验
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作者 赵登峰 《中学理科园地》 2024年第2期67-68,共2页
通过DIS可以回避数学知识不足,直观地给出变力作用一段时间的冲量以及物体在此变力作用下动量的变化量,直接比较二者数值,验证了变力作用下的动量定理。
关键词 dis 变力 冲量 动量定理
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DIS技术与科学类实验项目化再设计的融合
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作者 陈琳 《中国现代教育装备》 2024年第2期26-30,共5页
DIS技术凭借良好的兼容性及其在实验数据精度、效度与灵活度方面的优势,有助于深化课程内容的学习、推进教师的日常教学、关注学生的素养培育,是教育数字化转型在实验教学上的重要体现。DIS技术融合实验的项目化再设计,要以尊重课程标... DIS技术凭借良好的兼容性及其在实验数据精度、效度与灵活度方面的优势,有助于深化课程内容的学习、推进教师的日常教学、关注学生的素养培育,是教育数字化转型在实验教学上的重要体现。DIS技术融合实验的项目化再设计,要以尊重课程标准、侧重技术融合、看重情境引导、注重思维发展为原则,从而更好地助力实现实验教学变革。 展开更多
关键词 实验教学 数字化实验 dis技术
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以DIS实验促进高中物理教学的探究
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作者 张春艳 《学苑教育》 2024年第16期40-42,共3页
实验是物理这门学科的主要特征,教师在开展工作时,不仅要注重基础理论知识的传授,同时要重视实验教学的开展。而传统的物理实验,不论是在测量的精度、速度,以及数据处理方面,都存在一定局限,影响了物理教学的实效性。DIS实验作为一种运... 实验是物理这门学科的主要特征,教师在开展工作时,不仅要注重基础理论知识的传授,同时要重视实验教学的开展。而传统的物理实验,不论是在测量的精度、速度,以及数据处理方面,都存在一定局限,影响了物理教学的实效性。DIS实验作为一种运用先进技术进行实验教学的方式,对于培养学生的学科综合能力,促进高效课堂的构建均有重要帮助。基于此,文章从多方面概述了以DIS实验促进高中物理教学的路径。 展开更多
关键词 dis实验 高中物理 教学路径
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DIS数字化信息系统在高中物理实验教学中的应用研究
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作者 梁新龙 《课堂内外(高中版)》 2024年第29期77-79,共3页
高中物理教学中,DIS数字化信息系统的运用不仅可以丰富物理实验教学方法,还可以补充实验教学内容,调动学生的主观能动性,为学生创新思维能力提升提供支持。所以高中物理教师在物理实验教学中需要结合教材内容,找准DIS数字化信息系统引入... 高中物理教学中,DIS数字化信息系统的运用不仅可以丰富物理实验教学方法,还可以补充实验教学内容,调动学生的主观能动性,为学生创新思维能力提升提供支持。所以高中物理教师在物理实验教学中需要结合教材内容,找准DIS数字化信息系统引入点,转变传统物理教学模式,为学生提供实践操作机会,确保学生能够真正理解物理知识,提升实践操作能力。 展开更多
关键词 dis数字化信息系统 物理实验 物理素养 高中物理
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Energy,exergy,economic and environmental comprehensive analysis and multi-objective optimization of a sustainable zero liquid discharge integrated process for fixed-bed coal gasification wastewater
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作者 Yanli Zhang Zhengkun Hou +7 位作者 Dong Yao Xiaomin Qiu Hongru Zhang Peizhe Cui Yinglong Wang Jun Gao Zhaoyou Zhu Limei Zhong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期341-354,共14页
For a long time,China's regional water resource imbalance has restricted the development of coal chemical industry,and it is imperative to achieve zero liquid discharge(ZLD).Therefore,the game relationship between... For a long time,China's regional water resource imbalance has restricted the development of coal chemical industry,and it is imperative to achieve zero liquid discharge(ZLD).Therefore,the game relationship between technical indicators,costs and emissions in ZLD process of fixed-bed coal gasification wastewater treatment process should be explored in detail.According to the accurate model,the simulation for ZLD of fixed-bed coal gasification wastewater treatment process is established,and this process is assessed from the perspective of thermodynamics,economy,and environment.The total energy consumption of ZLD process before optimization is 4.032×10^(8)W.The results of exergy analysis show exergy destruction of ZLD process is 94.55%.For economic and environmental results,the total annual cost is 1.892×10^(7)USD·a^(-1)and the total environmental impact is 4.782×10^(-8).The total energy consumption of the optimal six-step ZLD process based on multi-objective optimization is 4.028×10^(8)W.The CO_(2)content in the treated wastewater is 0.1%.This study will have an important role in promoting the establishment of the ZLD process for coal chemistry industry. 展开更多
关键词 Waste water Case study ENERGY EXERGY ECONOMY Environment
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罕见抗-Di^(b)致严重胎儿新生儿溶血病的实验室检测与相关研究
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作者 廖志坚 贾双双 +5 位作者 温机智 莫春妍 邵媛 张润青 罗广平 姬艳丽 《中国输血杂志》 CAS 2024年第2期158-164,共7页
目的对1例高频抗体导致的胎儿新生儿溶血病(hemolytic disease of the fetus and newborn,HDFN)进行检测、鉴定及配血。方法对患儿进行新生儿溶血试验,对母亲进行血清学意外抗体鉴定,并对母亲红细胞进行常见高频抗原鉴定;对检出抗体进行... 目的对1例高频抗体导致的胎儿新生儿溶血病(hemolytic disease of the fetus and newborn,HDFN)进行检测、鉴定及配血。方法对患儿进行新生儿溶血试验,对母亲进行血清学意外抗体鉴定,并对母亲红细胞进行常见高频抗原鉴定;对检出抗体进行IgG分型检测,并用流式细胞术进行单核细胞体外吞噬致敏红细胞试验,以检测抗体相关的吞噬率;对患儿母亲、父亲及舅舅进行相关红细胞血型基因测序;利用稀释的母亲血浆和抗人球卡法,在献血者中进行大规模相合血液的筛选。结果产妇鉴定为Di(b-)稀有血型,产生了抗-Di b(效价512)并导致了严重的HDFN;抗-Di b亚型分型为IgG1和IgG2型,单核细胞体外吞噬效率为88.83%(74.7/84.09);产妇亲属中没有相合献血者,后续从5520名献血者中筛选到2例Di(b-)相合血液,患儿接收输血治疗后康复出院。后续在51334名献血者中筛查到17名Di(b-)献血者,该数据表明Di(b-)在广州地区献血者中的分布频率约为三千分之一(0.033%,17/51334)。结论综合利用血型血清学及分子生物学方法诊断了抗-Di b所致的严重HDFN,建立了1种有效大规模筛查Di(b-)稀有血型的方法并找到相合血液,为建立Di(b-)稀有血型库奠定了基础。 展开更多
关键词 抗-di b di(b-)稀有血型 胎儿新生儿溶血病
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