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HPLC法测定硝呋太尔的4种中间体的含量和有关物质 被引量:2
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作者 孙国祥 邓海莹 李闫飞 《西北药学杂志》 CAS 2011年第5期334-337,共4页
目的建立硝呋太尔合成过程中4种中间体2-(甲硫基甲基)-氧杂环丙烷(MMOP),3-甲硫基-2-羟基-丙基肼(HMPL),N-氨基-5-甲硫基甲基-2-唾唑烷酮(AMOD)和5-硝基糠醛(5-NFA)的HPLC分析方法。方法MMOP和5-NFA以70mmol·L^-1磷酸... 目的建立硝呋太尔合成过程中4种中间体2-(甲硫基甲基)-氧杂环丙烷(MMOP),3-甲硫基-2-羟基-丙基肼(HMPL),N-氨基-5-甲硫基甲基-2-唾唑烷酮(AMOD)和5-硝基糠醛(5-NFA)的HPLC分析方法。方法MMOP和5-NFA以70mmol·L^-1磷酸氢二钠溶液-甲醇(85:15)为流动相,HMPL和AMOD以70mmol.L^-1磷酸氢二钠溶液-乙腈(97:3)为流动相,MMOP、HMPL和5-NFA以AgilentZORBAXSB-Phenyl柱(250mm×4.6mm,5μm)分析,AMOD以AgilentEclipseXDB-C8柱(150mm×4.6mm,5μm)测定,检测波长分别为210,205,205和312nm。结果MMOP、HMPL、AMOD和5-NFA分别在7.4~266.4,26.0~2600,38.0~3800和18.5~1850μg·mL^-1范围内,峰面积与质量浓度呈良好的线性关系,平均回收率分别为99.9%,99.8%,100.1%和100.1%。4种中间体在酸、碱、氧化、直火和光照条件下的破坏实验时主成分峰与各降解产物及有关物质峰均能很好地分离。结论该方法简单、准确、重复性好,可用于硝呋太尔4种中间体的质量控制。 展开更多
关键词 HPLC 2-(甲硫基甲基)-氧杂环丙烷(MMOP) 3-甲硫基-2-羟基-丙基肼(HMPL) N-氨基-5-甲硫基甲基-2-噁唑烷酮(AMOD) 5-硝基糠醛(5-NFA) 硝呋太尔 有关物质
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Chiari Ⅰ畸形后颅窝MRI径线测量研究进展 被引量:2
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作者 唐怀波 谢明祥 《遵义医学院学报》 2013年第3期288-290,共3页
ChiariI畸形是一种先天性颅颈交界区畸形疾病,正常人群中发病率约为1%,于t891年由奥地利病理学家HansChiari首先报告而得名,是基于尸体解剖的研究,显示部分小脑、第四脑室及脑干向下移位,经枕骨大孔疝人椎管的一组先天性畸形。目... ChiariI畸形是一种先天性颅颈交界区畸形疾病,正常人群中发病率约为1%,于t891年由奥地利病理学家HansChiari首先报告而得名,是基于尸体解剖的研究,显示部分小脑、第四脑室及脑干向下移位,经枕骨大孔疝人椎管的一组先天性畸形。目前对ChiariI畸形的发病机制仍未阐明,以后颅窝拥挤学说最为流行,有研究旧0认为是起源于胚胎中轴叶轴旁的枕骨原节发育不良,导致后颅窝不能容纳正常发育的神经组织,由于颅内压力变化关系,小脑幕上抬代偿空间极为有限,导致小脑扁桃体不同程度的呈舌样下移至椎管内,可下疝至第3—4颈椎水平,引起脑脊液循环障碍, 展开更多
关键词 Amod—chiari畸形 后颅窝径线测量 磁共振成像
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A computational model of topological and geometric recovery for visual curve completion 被引量:2
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作者 Hongwei Lin Zihao Wang +2 位作者 Panpan Feng Xingjiang Lu Jinhui Yu 《Computational Visual Media》 2016年第4期329-342,共14页
Visual curve completion is a fundamental problem in understanding the principles of the human visual system. This problem is usually divided into two problems: a grouping problem and a shape problem.On one hand, thoug... Visual curve completion is a fundamental problem in understanding the principles of the human visual system. This problem is usually divided into two problems: a grouping problem and a shape problem.On one hand, though perception of the visually completed curve is clearly a global task(for example,a human perceives the Kanizsa triangle only when seeing all three black objects), conventional methods for solving the grouping problem are generally based on local Gestalt laws. On the other hand, the shape of the visually completed curve is usually recovered by minimizing shape energy in existing methods.However, not only do these methods lack mechanisms to adjust the shape of the recovered visual curve using perceptual, psychophysical, and neurophysiological knowledge, but it is also difficult to calculate an explicit representation of the visually completed curve. In this paper, we present a systematic computational model for generating a visually completed curve. Firstly, based on recent studies of perception, psychophysics, and neurophysiology, we formulate a grouping procedure based on the human visual system by seeking a minimum Hamiltonian cycle in a graph, solving the grouping problem in a global manner. Secondly, we employ a B′ezier curve-based model to represent the visually completed curve. Not only is an explicit representation deduced, but we also present a means to integrate knowledge from related areas, such as perception, psychophysics, and neurophysiology, and so on. The proposed computational model has been validated using many modal and amodal completion examples, and desirable results were obtained. 展开更多
关键词 modal completion amodal completion grouping problem shape problem human visual system
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