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11.
总结了23例氯化锶[^89Sr]注射液治疗肿瘤骨转移的护理。23例患者经ECT骨扫描检查证实骨转移病灶为单处和多处不等,主要临床表现为玩固性骨疼痛,活动能力受限。给予氯化锶[^89Sr]注射治疗,并采取以下护理措施:注射前疼痛评估,注射前心理护理,治疗后跟踪随访,不良反应的观察及应对护理等。 相似文献
12.
通过对比创造性思维和数学建模的基本过程,论述创造性思维在数学建模过程中的具体应用,说明建立数学模型的过程是创造性思维过程的具体体现,而创造性思维是数学建模过程的核心和灵魂。 相似文献
13.
Jesper Haglund Emil Melander Matthias Weiszflog Staffan Andersson 《Research in Science & Technological Education》2017,35(3):349-367
Background: University physics students were engaged in open-ended thermodynamics laboratory activities with a focus on understanding a chosen phenomenon or the principle of laboratory apparatus, such as thermal radiation and a heat pump. Students had access to handheld infrared (IR) cameras for their investigations.Purpose: The purpose of the research was to explore students’ interactions with reformed thermodynamics laboratory activities. It was guided by the research question: How do university physics students make use of IR cameras in open-ended investigation of thermal radiation as a phenomenon?Sample: The study was conducted with a class of first-year university physics students in Sweden. The interaction with the activities of four of the students was selected for analysis. The four students are males.Design and methods: We used a qualitative, interpretive approach to the study of students’ interaction. The primary means of data collection was video recording of students’ work with the laboratory activities and their subsequent presentations. The analysis focused on how IR cameras helped students notice phenomena relating to thermal radiation, with comparison to previous research on students’ conceptions of thermal radiation.Results: When using the IR camera, students attended to the reflection of thermal radiation on shiny surfaces, such as polished metals, windows or a whiteboard and emissive properties of surfaces of different types. In this way, they went beyond using the technology as a temperature probe. Students were able to discuss merits and shortcomings of IR cameras in comparison with digital thermometers.Conclusions: With the help of IR cameras, university physics students attend to thermal phenomena that would otherwise easily go unnoticed. 相似文献
14.
T Padmanabhan 《Resonance》2007,12(2):4-16
The discovery of the cosmic microwave background radiation in 1965 was a defining moment in the history of cosmology — the
science that deals with the universe as a whole, its origin, evolution and future. This discovery was recognized with Nobel
Prizes to Penzias and Wilson in 1978. The Nobel Prize in Physics for 2006 further acknowledged the importance of the study
of this background radiation. The precise measurement of the spectrum of this radiation and its variation across the sky have
helped our understanding of the evolution of structures in the universe. This article explains these discoveries and their
importance.
T Padmanabhan is a professor at IUCAA, Pune. He is interested in all aspects of theoretical physics, and especially in those
in which gravity plays a role. 相似文献
15.
16.
研究四能级原子的自发辐射。原子激发态是不稳定的,其必然会自发地向低能级衰变,产生自发辐射现象。本文针对四能级原子仅存在自发辐射的情况,基于量子力学和Kraus算子理论,利用约化密度矩阵方法,得到四能级原子自发辐射的密度矩阵元演化规律,从而分析量子态相干特性。 相似文献
17.
对电荷、电流连续分布系统进行研究,分析、演绎推证出电偶极子辐射公式,从而解释了有关电偶极子辐射的规律及有关物理量的意义. 相似文献
18.
基于欧拉-伯努利梁理论,设计了一种新型的微型同位素辐射能收集器二维机电模型。该模型解决了一维机电模型无法涵盖的诸多问题。算例分析表明:本模型能较准确地描述实验过程和预测实验结果。通过对结果进行分析,得出了影响微悬臂梁的位移、梁的往返周期和梁中存储能量的一系列因素。 相似文献
19.
Suneesh Kumar Pachathundikandi Earaly Thomas Varghese 《Indian journal of clinical biochemistry : IJCB》2006,21(2):114-117
Blood zinc protoporphyrin (ZPP), serum total protein (TP), and total cholesterol (TC) levels in automobile workshop workers
in relation to lead toxicity were analysed. In the present study, automobile workshop workers (healthy male workers at an
age between 28 and 35 from four major automobile workshops in Kottayam, Kerala State, India) and the control (male healthy
adults at an age between 28 and 35 residing at Aymanam, a distant village at Kottayam District, Kerala having reduced or no
chance of lead exposure) displayed significant difference in blood lead (BPb) and blood ZZP (BZPP) level. The mean value of
BPb in automobile workshop workers was 15.76±0.33 μg/dl, while in the control it was 8.20±0.15 μg/dl. In automobile workshop
workers, the mean value of BZPP was 34.2±0.62 μg/dl. The control group exhibited a mean of 11.5±0.22 μg/dl. Automobile workshop
workers exhibited significant increase in BZPP was corresponding to the increase in BPb level. The total protein levels estimated
in automobile workshop workers showed significant decrease compared to control individuals, but was within the reference range
of healthy individuals. The mean value of TP level in automobile workshop workers and control was 6.9±0.13 g/dl and 7.71±0.18
g/dl, respectively. There was no significant difference in blood haemoglobin (BHb) level among the automobile workshop workers
and control. The serum TC level in automobile workshop workers showed significant decrease compared to the control individuals,
but was with in the reference range of healthy individuals. The mean level of serum TC in automobile workshop workers was
162.00±3.44 mg/dl and the same in control was 172.86±4.32 mg/dl. The present study affirms occupational lead toxicity in automobile
workshop workers and its effect on serum protein and cholesterol levels. 相似文献
20.