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51.
本文探究了磁共振弥散加权成像(diffusion-weighted magnetic resonance imaging,DWMRI)对周围型非小细胞癌(NSCLC)的诊断意义及放化疗疗效的评估作用。选取2016年1月~2019年1月于我院就诊的NSCLC患者100例,放疗处方剂量46~66 Gy,单次剂量2.0~2.2 Gy,每日放疗1次,每周5次,并配合化疗治疗。放化疗前后应用CT与DWMRI观察放化疗前后近期疗效、DWMRI高信号表达、表观扩散系数(apparent diffusion coefficient,ADC)值变化以及影响预后的因素。研究结果显示,CT与MRI图像评价放疗前后100例NSCLC患者中,CR组28例,PR组53例,NR组19例(PD 2例,SD 17例),治疗有效率为81.00%,CR组和PR组患者1、2、3年无进展生存率分别为89.29%、46.42%、39.28%和56.60%、37.74%、33.97%,差异具有统计学意义(χ2=24.500,P=0.000)。放疗后肺癌原发灶DWMRI高信号消失35例,未消失65例;淋巴结高信号完全消失者40例,未完全消失者35例;肺癌原发灶、淋巴结完全消失者18例,未完全消失者29例。两组NSCLC患者1、2、3年无进展生存率分别为71.25%、34.52%、25.00%与35.64%、4.50%、4.50%,差异具有统计学意义(χ2=25.790,P=0.000)。原发灶与转移淋巴结放疗前CR、PR、NR组ADC值逐渐升高,而ΔADC值逐渐降低,放疗后治疗效果CR组最优,PR组优于NR组(P<0.05);高信号完全消失组,原发灶放疗前后ADC值均低于高信号部分消失组,而ΔADC值较高;转移淋巴结高信号完全消失组放疗前后ADC值、ΔADC均高于高信号部分消失组,差异具有统计学意义(P<0.05)。本文还进行了Cox回归模型多因素预后分析,发现TNM分期及DWMRI为影响预后的主要因素。本研究证实DWMRI对肿瘤治疗的微环境变化较为敏感,ADC值的变化可以在早期监视肿瘤诊断效果,为临床NSCLC治疗与诊断提供参考依据。 相似文献
52.
Biodegradable poly(l-lactide) (PLA) ultrafine fibers containing nanosilver particles were prepared via electrospinning. Morphology of the Ag/PLA fibers and distribution of the silver nanoparticles were characterized. The release of silver ions from the Ag/PLA fibers and their antibacterial activities were investigated. These fibers showed antibacterial activities (microorganism reduction) of 98.5% and 94.2% against Staphylococcus aureus and Escherichia coli, respectively, because of the presence of the silver nanoparticles. 相似文献
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54.
Sara Katz Moshe Stupel 《International Journal of Mathematical Education in Science & Technology》2016,47(3):421-439
Individuals and societies that can use mathematics effectively in this period of rapid changes will have a voice on increasing the opportunities and potentials which can shape their future. This has brought affective characteristics, such as self-efficacy, that affect mathematics achievement into focus of the research. Teacher efficacy refers to the extent to which a teacher feels capable to help students learn, influence students’ performance and commitment, and thus plays a crucial role in developing the student in all aspects. In this study, we used two sources of efficacy beliefs, mastery experiences and physiological and emotional states, in an interesting and challenging seven month workshop, as tools to foster teacher efficacy for six elementary-school teachers who were frustrated and wanted to leave their job. Our aim was to study the nature of these teachers’ efficacy in order to change it. In this qualitative action research, we used open interviews, non-participant observations and field notes. Results show that these teachers became efficacious, their students’ achievements and motivation were enhanced, and the school climate was changed. Qualitative inquiry of this construct sheds light on efficacy beliefs of mathematics teachers. Nurturing teacher efficacy has borne much fruit in the field of mathematics in school. 相似文献
55.
Monitoring the quality consistency of Fufang Danshen Pills using micellar electrokinetic chromatography fingerprint coupled with prediction of antioxidant activity and chemometrics
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Zhengchao Ji Wanyang Sun Guoxiang Sun Jin Zhang 《Journal of separation science》2016,39(15):3019-3027
A fast micellar electrokinetic chromatography fingerprint method combined with quantification was developed and validated to evaluate the quality of Fufang Danshen Pills, a traditional Chinese Medicine, which has been used in the treatment of cardiovascular system diseases, in which the tetrahedron optimization method was first used to optimize the background electrolyte solution. Subsequently, the index of the fingerprint information amount of I was performed as an excellent objective indictor to investigate the experimental conditions. In addition, a systematical quantified fingerprint method was constructed for evaluating the quality consistency of 20 batches of test samples obtained from the same drug manufacturer. The fingerprint analysis combined with quantitative determination of two components showed that the quality consistency of the test samples was quite good within the same commercial brand. Furthermore, the partial least squares model analysis was used to explore the fingerprint–efficacy relationship between active components and antioxidant activity in vitro, which can be applied for the assessment of anti‐oxidant activity of Fufang Danshen pills and provide valuable medicinal information for quality control. The result illustrated that the present study provided a reliable and reasonable method for monitoring the quality consistency of Fufang Danshen pills. 相似文献
56.
《应用有机金属化学》2017,31(1)
Five new organotin(IV) complexes of composition [Bz2SnL1]n ( 1 ), [Bz3SnL1H⋅H2O] ( 2 ), [Me2SnL2⋅H2O] ( 3 ), [Me2SnL3] ( 4 ) and [Bz3SnL3H]n ( 5 ) (where L1 = (2S )‐2‐{[(E )‐(4‐hydroxypentan‐2‐ylidene)]amino}‐4‐methylpentanoate, L2 = (rac )‐2‐{[(E )‐1‐(2‐hydroxyphenyl)methylidene]amino}‐4‐methylpentanoate and L3 = (2S )‐ or (rac )‐2‐{[(E )‐1‐(2‐hydroxyphenyl)ethylidene]amino}‐4‐methylpentanoate) were synthesized and characterized using 1H NMR, 13C NMR, 119Sn NMR and infrared spectroscopic techniques. The crystal structure of 2 reveals a distorted trigonal‐bipyramidal geometry around the tin atom where the oxygen atoms of the carboxylate ligand and a water ligand occupy the axial positions, while the three benzyl ligands are located at the equatorial positions. On the other hand, the analogous derivative of enantiopure L3H ( 5 ) consists of polymeric chains, in which the ligand‐bridged tin atoms adopt the same trans ‐Bz3SnO2 trigonal‐bipyramidal configuration and are now coordinated to a phenolic oxygen atom instead of H2O. In 2 , the OH hydrogen of the ketoimine substituent has moved to the nearby nitrogen atom while in the salicylidene derivative 5 , the OH is located almost midway between the phenolic oxygen atom and the nitrogen atom of the CN group. For the dibenzyltin derivative 1 , a polymeric chain structure is observed as a result of a long intermolecular Sn⋅⋅⋅O bond involving the exocyclic carbonyl oxygen atom from the tridentate ligand of a neighbouring tin‐complex unit. The tin atom in this complex has distorted octahedral coordination geometry. In contrast, the racemic dimethyltin(IV) complexes 3 and 4 display discrete monomeric structures with a distorted octahedral‐ and trigonal‐bipyramidal geometry, respectively. The structures show that the coordination mode of the Schiff base ligand depends primarily on the number of bulky benzyl ligands (R) at the tin atom, as indeed found in the structures of related complexes where R = phenyl. With three bulky R groups, the tridentate chelating O,N,O coordination mode is preferred, whereas with fewer or less bulky R ligands, only the carboxylate and hydroxy groups are involved, which leads to polymers. Larvicidal efficacies of two of the new tribenzyltin(IV) complexes ( 2 and 5 ) were assessed on the second larval instar of Anopheles stephensi mosquito larvae and compared with two triphenyltin(IV) analogues, [Ph3SnL1H]n and [Ph3SnL3H]n . The results demonstrate that the compounds containing Sn–Ph ligands are more effective than those with Sn–Bz ligands. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
57.
Saturation Effects on Immunopathogenic Mechanism of Psoriasis:A theoretical approach 总被引:1,自引:0,他引:1
Psoriasis vulgaris is a common chronic autoimmune inflammatory skin disease characterized by T-cell mediated hyper proliferation of keratinocytes.This type of skin disorder is characterized by macroscopic and also microscopic skin alterations.It was observed that,psoriatic lesions are sharply demarcated,red and slightly raised lesions along with silver whitish scales.The striking feature of T-cell mediated chronic psoriatic lesions are the epidermal infiltration of predominantly oligoclonal CD8~+T-cells ... 相似文献
58.
This study researches the synthesis of Arginine-Glycine-Asparti (RGD) peptide modification of copolymer: poly (lactic acid-co-L-lysine) (PLA-PLL-RGD) and the preparation of mitoxantrone (DHAQ)-loaded PLA-PLL-RGD nanoparticles (DHAQ-NP), and evaluates antitumor efficacy of exercise and DHAQ-NP in hepatoma and breast carcinoma. The experimental findings demonstrate that DHAQ-NP group have more significant antitumor efficacy than DHAQ group in hepatoma-bearing mice and breast carcinoma-bearing mice. Compared with DHAQ-NP group, the antitumor efficacy of Exercise+DHAQ-NP group are significantly lower in breast carcinoma-bearing mice. However, the antitumor efficacy of Exercise+DHAQ-NP group have no significant change in hepatoma-bearing mice. This suggests that the same exercise intensity can cause different antitumor efficacies for different tumors undergoing targeted therapies. 相似文献
59.
远程荧光体白光发光二极管的发光性能 总被引:6,自引:0,他引:6
研究了高色温和低色温两种球冠状远程荧光粉白光LED在不同电流、不同热沉温度下的发光性能差异.结果表明:在大电流下,LED有源层内由于量子限制斯塔克效应使其峰值波长向短波方向移动,偏离了高色温荧光粉的最佳激发波长,更加接近低色温荧光粉的最佳激发波长.高色温LED的相关色温随电流增加呈上升趋势,低色温LED的相关色温随电流增加呈下降趋势,与它们的量子效率变化引起的色坐标漂移有很大关系.两种LED量子效率和发光效能随热沉温度的升高均呈略微增大的趋势;其中,高色温LED的量子效率和发光效能随电流的增大而减小,而低色温LED的量子效率和发光效能则随电流的增大而升高;高色温LED发光性质较低色温LED好,但色特性的稳定程度不如低色温LED. 相似文献
60.
Kathryn A. Baldwin 《School science and mathematics》2014,114(5):206-213
This study examined prospective elementary education majors' science teaching self‐efficacy while they were enrolled in an introductory geology lab course for elementary education majors. The Science Teaching Efficacy Belief Instrument Form B (STEBI‐B) was administered during the first and last lab class sessions. Additionally, students were asked an open‐ended question to describe their experience in the education majors' geology lab. The results of the STEBI‐B were analyzed using paired t‐tests to determine whether the students changed their personal science teaching efficacy (PSTE) and science teaching outcome expectancy (STOE). Results of this study indicate a significant increase in PSTE. No significant differences were found in STOE. This study suggests that science content courses designed for education majors may lead to a positive change in science teaching self‐efficacy and has implications for teacher educators in preparing science content courses for their teacher preparation program. 相似文献