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61.
目的 对瓦里安Eclipse三维治疗计划系统(3D-TPS)进行临床应用前的系统参数测量与验证,并进行分析讨论.方法用三维水箱和剂量仪对3D-TPS所需的临床参数进行检测,并将监测结果输入到3D-TPS中,验证其符合程度,在射野内用电离室对水箱中感兴趣的四处点剂量进行测量,并对电子束"虚源"位置进行测量,最后再分别验证3D-TPS中计算剂量和电子束"虚源"位置(即有效源皮距)的实测值与计划值之间的符合性.结果 3D-TPS的计算曲线与瓦里安Clinac 23EX直线加速器上实测参数曲线符合度很好,并且实测剂量与3D-TPS中计算剂量相对误差在-0.55%~1.12%之间,平均误差为0.66%.电子束"虚源"中的有效源皮距实测值与瓦里安公司提供的有效源皮距参考值之间的相对误差在1.27%~1.86%之间,平均误差为1.62%.结论瓦里安Eclipse 3D-TPS能很好地满足三维适形及调强放射治疗的临床需要.  相似文献   
62.
目的 建立家兔全血细胞复阻抗谱的数据特征参数.方法 在0.01~100MHz频率范围,利用4294A阻抗分析仪测量了10只家兔30个血液样本的交流阻抗,通过Bode图、Nyquist图、Nichols图谱的数据分析,建立了家兔血液细胞电生理的频率特性.结果 (1)家兔血液细胞阻抗幅模最和相位角具有频率依从性.(2)家兔血液细胞阻抗谱具有两个特征频率:第1特征频率fC1=2.58MHz,第2特征频率fC2=5.21 MHz.结论 通过阻抗谱分析法可以确定血液细胞频率特性.  相似文献   
63.
西洋参制剂抗疲劳作用的实验研究   总被引:2,自引:0,他引:2  
[目的]通过小鼠动物实验验证西洋参制剂的抗疲劳作用。[方法]采用"保健食品功能学评价程序和检验方法"中抗疲劳实验规定的方法,以小鼠为实验对象,研究西洋参制剂对小鼠体重、游泳时间、爬杆时间及血清尿素氮、血乳酸、肝糖原等生化指标的影响。[结果]西洋参制剂能明显延长小鼠负重游泳时间、爬杆时间;能明显降低小鼠运动后的血清尿素氮和血乳酸的含量;且差异均有显著性。[结论]西洋参制剂具有抗疲劳作用。  相似文献   
64.
65.
We adopt an acetone vapour-assisted method to grow high quality single-crystalline microplates of two-dimensional (2D) perovskite, 2-phenylethylammonium lead bromide [(C6H5C2H4NH3)2PbBr4]. The microplates, converted from the spin-coated films, are well-defined rectangles. Temperature dependent photoluminescence (PL) spectroscopy shows that the band gap PL is enhanced markedly with increasing temperature up to 218 K, accompanied by the quenching of the PL related to the trap states, which perhaps results from the exciton–phonon couplings. The optical phonon energy around 50 meV and the exciton binding energy around 120 meV are derived by fitting the band gap PL linewidths and intensities at different temperatures, respectively.

We report an acetone vapour-assisted method to grow single-crystalline 2D perovskite microplates and find their temperature-enhanced photoluminescence.  相似文献   
66.
Objectives (1) To develop an automated eligibility screening (ES) approach for clinical trials in an urban tertiary care pediatric emergency department (ED); (2) to assess the effectiveness of natural language processing (NLP), information extraction (IE), and machine learning (ML) techniques on real-world clinical data and trials.Data and methods We collected eligibility criteria for 13 randomly selected, disease-specific clinical trials actively enrolling patients between January 1, 2010 and August 31, 2012. In parallel, we retrospectively selected data fields including demographics, laboratory data, and clinical notes from the electronic health record (EHR) to represent profiles of all 202795 patients visiting the ED during the same period. Leveraging NLP, IE, and ML technologies, the automated ES algorithms identified patients whose profiles matched the trial criteria to reduce the pool of candidates for staff screening. The performance was validated on both a physician-generated gold standard of trial–patient matches and a reference standard of historical trial–patient enrollment decisions, where workload, mean average precision (MAP), and recall were assessed.Results Compared with the case without automation, the workload with automated ES was reduced by 92% on the gold standard set, with a MAP of 62.9%. The automated ES achieved a 450% increase in trial screening efficiency. The findings on the gold standard set were confirmed by large-scale evaluation on the reference set of trial–patient matches.Discussion and conclusion By exploiting the text of trial criteria and the content of EHRs, we demonstrated that NLP-, IE-, and ML-based automated ES could successfully identify patients for clinical trials.  相似文献   
67.

Aims

To evaluate the evidence of the effectiveness and safety of Chinese herbal medicine skin‐patches for patients with acute gouty arthritis.

Background

Acute gouty arthritis is a problem that can limit the level of activity and impair the quality of life. In China, many clinical studies have demonstrated that skin‐patches of Chinese herbal medicines benefit patients with acute gouty arthritis. However, the reported clinical effects vary.

Design

A systematic review and meta‐analysis of randomized controlled trials.

Data sources

Three English databases including CENTRAL (1993 to February 2017), PubMed (1966 to February 2017) and EMBASE (1974 to February 2017) and four Chinese databases including Chinese National Knowledge Infrastructure, Chinese VIP Information, SinoMed and Wanfang (all, 1949 ‐ February 2017) were searched. Randomized controlled trials that compared skin‐patches of Chinese herbal medicine with or without conventional treatments to conventional treatments, no treatment or a placebo treatment for patients with acute gouty arthritis were included.

Review methods

We conducted a systematic review and meta‐analysis following the Cochrane process. Two authors selected the studies, extracted the data and evaluated the risk of bias of the included trials.

Results

Nineteen studies met our inclusion criteria. After synthesizing the data, the results showed that skin‐patches of CHM combined with Western medicine seemed to be more effective than Western medicine alone for pain relief in patients with acute gouty arthritis and had fewer adverse events.

Conclusion

Due to the quality of the data, larger and more rigorously designed clinical trials with proper outcome measures are necessary.  相似文献   
68.
69.
Aurivillius oxides with an intergrowth structures have been receiving increasing interest because of their special structures and potential outstanding ferroelectric properties. In this work, Bi3LaTiNbFeO12–Bi5Ti3FeO15 and Bi3TiNbO9–Bi3LaTiNbFeO12 compounds were successfully synthetised using a simple solid-state reaction method. X-Ray diffraction patterns and scanning transmission electron microscopy high angle annular dark field (STEM-HAADF) images confirm the 2–3 and the 3–4 intergrowth structures in Bi3TiNbO9–Bi3LaTiNbFeO12 and Bi3LaTiNbFeO12–Bi5Ti3FeO15 compounds, respectively. A superlattice-like distortion in these oxides was proposed resulting from the combination of sub-lattices with different a and b parameters, which was validated by XRD refinements and Raman spectra. Polarization-electric field tests and pulsed polarization positive-up negative-down measurements demonstrate that such superlattice-like structures can effectively enhance the intrinsic ferroelectric polarization and coercive field of these oxides, especially when compared with their component oxides Bi3TiNbO9, Bi3LaTiNbFeO12 and Bi5Ti3FeO15. Simultaneously, ferroelectric Curie temperatures of Bi3TiNbO9–Bi3LaTiNbFeO12 and Bi3LaTiNbFeO12–Bi5Ti3FeO15 oxides are lowered because of the internal stress in the superlattice-like structure. Nevertheless, the paramagnetism of the samples is hardly influenced by their structure, while mainly related to their iron content, in which iron has a similar effective magnetic moment around 3.4–3.9.

Aurivillius oxides with an intergrowth structures have been receiving increasing interest because of their special structures and potential outstanding ferroelectric properties.  相似文献   
70.
BackgroundThromboelastography (TEG) provides global assessment of hemostatic function and has been recommended to monitor potential coagulopathies during pregnancy in which hypercoagulable state is favored. In present study, we established the reference intervals (RIs) of the TEG parameters (R, K, MA, and α‐angle) with Chinese pregnant women of third trimester. In addition, we examined the diagnostic efficacies of the TEG parameters in the patients diagnosed of gestational hypertension (GH), gestational diabetes mellitus (GDM), or preeclampsia (PE).MethodsWith specified including and excluding criteria, non‐pregnant controls, healthy pregnant women, and pregnant women with GH, GDM, or PE had their venous blood drawn at Beijing Obstetrics and Gynecology Hospital, followed by TEG tests performed in the clinical laboratory.ResultsThe RIs determined with the healthy pregnant women (in third trimester) for R, K, MA, and α‐angle were 4.0‐7.7, 1.2‐3.2, 51.9‐70.1, and 41.4‐74.4, respectively. When compared with the healthy pregnancy group, the K value was significantly decreased in GH patients but increased in PE patients; MA was significantly lower in the PE group. In the receiver operating characteristic curve (ROC) analyses, K value was able to efficiently distinguish normal pregnancy from the GH patients, with an AUC of 0.86 which is far better than those of R (AUC = 0.57) and MA (AUC = 0.56). For the PE patients, the AUC of MA (0.69) was significantly greater than that of R (0.50).ConclusionsThromboelastography may provide more accurate experimental basis for monitoring coagulation functions especially in pregnant women with complications of GH and PE.  相似文献   
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