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基因DPT在胃癌患者中的表达情况分析
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作者 杨翠英 陈奕明 《大理大学学报》 2024年第10期40-43,共4页
目的:研究基因DPT在胃癌组织及远癌组织中的表达情况。方法:基于TCGA数据库、Oncomine数据库和GEPIA数据库,筛选出在胃癌组织中可能异常表达且与预后相关的基因。收集胃癌组织和远癌组织标本,通过qRT-PCR和免疫组化技术检测目标基因在... 目的:研究基因DPT在胃癌组织及远癌组织中的表达情况。方法:基于TCGA数据库、Oncomine数据库和GEPIA数据库,筛选出在胃癌组织中可能异常表达且与预后相关的基因。收集胃癌组织和远癌组织标本,通过qRT-PCR和免疫组化技术检测目标基因在胃癌组织及远癌组织中的表达情况。结果:筛选出319个上调差异基因和556个下调差异基因,以DPT为目标基因进行后续研究。qRT-PCR和免疫组化结果表明,基因DPT在胃癌组织中的表达显著低于远癌组织,差异有统计学意义(P<0.05)。结论:基因DPT在胃癌组织与远癌组织中存在表达差异,可能与胃癌的发生相关,具体机制仍需进一步研究。 展开更多
关键词 胃癌 基因dpt 表达水平
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Comparative Pertussis Antibody Response of Nigerian Children to Diphtheria, Pertussis, Tetanus (DPT) and Pentavalent Vaccines
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作者 Emmanuel Eyo Ekanem Glory Ekpo Bassey +1 位作者 Henry Chima Okpara Eyong Komomo Ibor 《World Journal of Vaccines》 2020年第3期43-53,共11页
<strong>Background:</strong> In Nigeria Pentavalent vaccine had replaced Diphtheria-Pertussis- Tetanus [DPT] vaccine in the prevention of pertussis since 2012. <strong>Aims and Objectives:</strong... <strong>Background:</strong> In Nigeria Pentavalent vaccine had replaced Diphtheria-Pertussis- Tetanus [DPT] vaccine in the prevention of pertussis since 2012. <strong>Aims and Objectives:</strong> The aim of this study was to compare the anti-pertussis immunoglobin G (IgG) response of children who received DPT with those who received the pentavalent vaccine. <strong>Subjects and Methods:</strong> This study was carried out in Akpabuyo LGA of Cross River State from April to June 2016. It was a cross-sectional survey of anti-pertussis IgG levels in children aged 6 months to 5 years who received DPT and those who received pentavalent vaccine. IgG antibody levels were determined using enzyme-linked immunosorbent assay. The protective level was set at >11 DU according to manufacturer’s cut off point. <strong>Results:</strong> Seventy eight out of 230 children [33.9%] who had received DPT had protective levels of anti-pertussis IgG compared to 74 out of 192 children [38.5%] who had received pentavalent vaccine. The difference was not statistically significant [<em>p</em> = 0.61]. The median IgG antibody level in those who received DPT was 8.0 DU (interquartile range (IQR) 4.0 - 13.0) compared with 9.0 DU (IQR) 4.0 - 15.0 in those who received pentavalent vaccine [<em>p</em> = 0.18]. No single factor investigated predicted the development of protective levels of antibody in the multivariate analysis. <strong>Conclusion/Recommendation:</strong> There was no difference in the antipertussis antibody response between DPT and pentavalent vaccines recipients. Further study is needed to elucidate factors that could be responsible for low anti-pertussis antibody response in this population. 展开更多
关键词 Anti-Pertussis Immunoglobulin G Diphtheria-Pertussis-Tetanus pentavalent Vaccine COMPARATIVE
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Tetanus Toxin Antibody Levels in Pre-School Nigerian Children after Three Doses of Diphtheria-Pertussis-Tetanus/Pentavalent Immunization: A Cross-Sectional Study
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作者 Emmanuel E. Ekanem Helen O. Uket Henry C. Okpara 《World Journal of Vaccines》 2018年第2期39-52,共14页
Background: Post-neonatal tetanus is an important problem. Prevention of tetanus in Nigeria is via immunization with three doses of Diphtheria-Pertussis-Tetanus (DPT)/Pentavalent vaccine at 6, 10 and 14 weeks. The ant... Background: Post-neonatal tetanus is an important problem. Prevention of tetanus in Nigeria is via immunization with three doses of Diphtheria-Pertussis-Tetanus (DPT)/Pentavalent vaccine at 6, 10 and 14 weeks. The anti-tetanus antibody levels of these children are not known after they had received DPT3/Pentavalent vaccines. Aim: This work was to determine the anti-tetanus antibody (IgG) response in Nigerian children aged six months to five years who had received three doses of DPT vaccine in early infancy. Methods: Children aged six months to five years who were attended to in the University of Calabar Teaching Hospital for acute illnesses were recruited. Their anti-tetanus IgG levels were measured using Enzyme Linked Immunosorbent Assay (ELISA). The optimal cut-off level of ≥0.1 IU/ml was used as the protective level. Data was analysed using the Statistical Package for Social Sciences (SPSS) version 20.0 with simple proportions and percentages. Students’ “t” test and ANOVA were used to compare quantitative variables while Chi-square and Fisher’s exact test were used to compare categorical data. Results: Four hundred and eighteen children participated in the study. The mean IgG antibody level was 1.021 ± 0.9 IU/ml. Four hundred children (95.7%) had protective levels of antibodies. The highest proportion of subjects with protective levels was in infants, 6 - 11 months (99%) and lowest in children aged 36 - 47 months (92.2%). Conclusion: The proportion of children with protective levels was above 90% in all age groups studied. The current national immunization schedule is adequate. Further studies in older age groups are needful. 展开更多
关键词 dpt/pentavalent Vaccine ANTIBODIES Response
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两维FFT和VD-DPT算法结合的LFM信号参数估计方法 被引量:1
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作者 庞存锁 苏灿生 张硕 《弹箭与制导学报》 北大核心 2023年第3期9-15,共7页
针对低信噪比下长序列LFM信号参数估计方法存在运算量大,实时性差的问题,提出了基于两维傅里叶变换(FFT)和变时延离散多项式相位变换(VD-DPT)相结合的LFM信号参数估计方法。该方法首先将一维长序列信号进行分解并组合成两维数组;其次,利... 针对低信噪比下长序列LFM信号参数估计方法存在运算量大,实时性差的问题,提出了基于两维傅里叶变换(FFT)和变时延离散多项式相位变换(VD-DPT)相结合的LFM信号参数估计方法。该方法首先将一维长序列信号进行分解并组合成两维数组;其次,利用VD-DPT算法对调频率参数进行初步估计,并以此为基础利用解线性调频变换(Dechirp)对两维数组进行最大值寻优处理。数值仿真表明:所提方法较传统DPT方法信噪比提高约2~3 dB,复乘运算量在调频率较大时,较Dechirp方法降低约1个数量级以上,具有明显的运算速度优势。该方法也可应用于高机动微弱目标的雷达检测系统。 展开更多
关键词 线性调频信号 两维FFT 变延时dpt变换 运算效率
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Supercritical Fluid Chromatography—Mass Spectrometry (SFC-MS) and MALDI-TOF-MS of Heterocyclic Compounds with Trivalent and Pentavalent Nitrogen in Cough Relief Medical Forms Tuxi and Cosylan 被引量:1
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作者 Ilia Brondz Anton Brondz 《American Journal of Analytical Chemistry》 2012年第12期870-876,共7页
Alkaloids are natural, semisynthetic or synthetic organic compounds, normally polar with basic chemical properties and containing at least one nitrogen atom in a heterocyclic ring. Some synthetic or semisynthetic subs... Alkaloids are natural, semisynthetic or synthetic organic compounds, normally polar with basic chemical properties and containing at least one nitrogen atom in a heterocyclic ring. Some synthetic or semisynthetic substances resemble the alkaloid architecture. Trivalent nitrogen in these substances is normal;however, some natural and semisynthetic alkaloids have pentavalent nitrogen. The drug pholcodine is a derivative of morphine. Pholcodine has very little addiction- developing effect. It is a semisynthetic alkaloid that was first synthesized in 1950 by Chabrier et al. Pholcodine possesses antitussive (cough relief) properties similar to codeine, morphine and ethylmorphine. The drug was used in liquid formulations as Tuxi and Tuxi Forte, and it is in present use in Tuxidrin as liquid mixture and in tablet form. Pholcodine is an Active Pharmacological Ingredient (API) in tablets and liquid mixtures. Leiras International and Weifa in Norway manufacture medical forms with pholcodine. Several impurities in pholcodine were described by J. Roe in 1997 and by Denk et al. in 2000 and 2002. In addition, several degradation products may be formed in liquid formulations under storage. Some of these products are related not to the original production of pholcodine but rather to its oxidation under storage. The appearance of degradation products strongly depends on the storage temperature and pH of the liquid phase. Pholcodine-N-oxide and pholcodine-N,N’-dioxide are among the degradation (oxidation) products;pholcodine can also degrade to morphine. There is little information about the toxicity of the N-oxide and no information on the N,N’-di- oxide of pholcodine. In this study, the fact that morphine is generated during the storage of formulations containing pholcodine is presented. Another antitussive mixture under the name Cosylan was analyzed to examine the oxidation of ethylmorphine to ethylmorphine-N-oxide. Ethylmorphine is the API in Cosylan. 展开更多
关键词 SFC TRIVALENT NITROGEN pentavalent NITROGEN Pholcodine-N-oxide Pholcodine-N N’-dioxide MORPHINE Cosylan Tuxi Tuxi FORTE Tuxidrin
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Mass Spectrometric Structure Elucidation of the Trivalent and Pentavalent Nitrogen Contaminants of Pholcodine in the Cough Relief Medical Form Tuxidrin
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作者 Ilia Brondz 《International Journal of Analytical Mass Spectrometry and Chromatography》 2013年第1期5-10,共6页
In the paper “Supercritical Fluid Chromatography-Mass Spectrometry (SFC-MS) and MALDI-TOF-MS of Heterocyclic Compounds with Trivalent and Pentavalent Nitrogen in Cough Relief Medical Forms Tuxi and Cosylan” [1], the... In the paper “Supercritical Fluid Chromatography-Mass Spectrometry (SFC-MS) and MALDI-TOF-MS of Heterocyclic Compounds with Trivalent and Pentavalent Nitrogen in Cough Relief Medical Forms Tuxi and Cosylan” [1], the presence of morphine and other degradation products of pholcodine in cough relief medical forms of Tuxi are discussed. Tuxiis recalled from the Norwegian market by Weifa pharmaceutical company, and hence it no longer presents problems to users and health authorities there;however, the medical form Tuxidrin, which contains a significant amount of pholcodine as the active pharmacological ingredient, is still marketed. In the present paper, Tuxidrin is analyzed to determine the presence of degradation products of pholcodine. The degradation of pholcodine to morphine has been discussed previously as a factor in the development of addiction to narcotics in young persons. The structures of the contaminants in Tuxidrin, such as oxides of pholcodine, are elucidated in the present paper. The toxicity and pharmacology of oxides of alkaloids have generally not been well studied, and very little is known about the toxicity and pharmacology of the degradation (oxidation) products of pholcodine: the N-oxide and the N, N'-dioxide of pholcodine. According to Brondz and Brondz[1], the N-oxide and possibly also the N, N'-dioxide are less toxic than the original alkaloids and possess greater pharmacological activity, and hence they may be a source of useful new semisynthetic drugs. The question of possible addiction to pholcodine oxides has not been studied, and the potential of these substances to provoke allergies is unclear. The recall of Tuxi from the Norwegian marketis mainly based on the fact that pholcodine causes significantly increased levels of IgE antibodies in sensitized patients. Tuxidrin contains pholcodine and has the same negative effect as Tuxi, namely provoking allergies or even anaphylactic shock. From this point of view, Tuxidrin has no advantage over Tuxi. These two medical forms only differ in one respect: Tuxidrin requires a prescription (prescription duty medicine), but Tuxi doesnot (prescription free medicine). This aspect is also discussed in the present paper. 展开更多
关键词 High Performance Liquid Chromatography-Mass Spectrometry (HPLC-MS) TRIVALENT NITROGEN pentavalent NITROGEN Pholcodine Alkaloids ADDICTION to NARCOTICS Allergy Tuxidrin Morphine Pholcodine-N-oxide 10-Hydroxy-pholcodine IgE Antibodies
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One-Electron-Addition to Pentavalent Phosphorus with the Phosphorus-Chlorine Bond as Acceptor Introducing a Fundamental Distinction in Substitution Mechanism between S<sub>N</sub>2(P) and S<sub>N</sub>2(C)
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作者 Henk M.Buck 《Open Journal of Physical Chemistry》 2019年第3期182-191,共10页
An electron-addition, under single-crystal conditions, to pentavalent phosphorus compounds as Cl-P (=O, S) Y, Z with the P-Cl bond as electron-accepting group, is selected as an additional model for SN2(P) like reacti... An electron-addition, under single-crystal conditions, to pentavalent phosphorus compounds as Cl-P (=O, S) Y, Z with the P-Cl bond as electron-accepting group, is selected as an additional model for SN2(P) like reactions. It is demonstrated that the geometric information stored in the tetrahedral configuration (substrate) can be transmitted in the corresponding trigonal bipyramidal (TBP) state for nucleophilic substitution. In this article, we focus on these specific mechanistic aspects of carbon and phosphorus. We consider our study as a contribution to the significance of these (bio)chemical intermediates. 展开更多
关键词 pentavalent PHOSPHORUS and Carbon Compounds σ*-Electron-Addition Single-Crystal Electron Spin Resonance (ESR) Model and Ab Initio Calculations Differences in SN2(C) vs. SN2(P) MECHANISM
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Evaluation of Disk Potentiation Test (DPT) and Double Disk Synergy Test (DDST) for The Detection of Metallo-β-Lactamases (MBLs) in Clinical Isolates of Bangladesh
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作者 Sumon Kumar Das Afzal Sheikh +4 位作者 Nikhat Ara Suma Mita Biswas Abhinandan Chowdhury Fatimah Az Zahra Chaman Ara Keya 《Advances in Infectious Diseases》 2023年第4期609-626,共18页
Objective: Increasing the emergence of Metallo-β-lactamase (MBL) producing gram-negative bacteria and their dexterous horizontal transmission demands rapid and accurate detection. This study was conducted to determin... Objective: Increasing the emergence of Metallo-β-lactamase (MBL) producing gram-negative bacteria and their dexterous horizontal transmission demands rapid and accurate detection. This study was conducted to determine a suitable method to promptly detect MBL-producing gram-negative bacteria. Methods: A total of 103 gram-negative bacteria were identified from various clinical samples at a tertiary care hospital in Dhaka city. MBL producers were detected by two phenotypic methods, the Disk Potentiation Test (DPT) and the Double Disk Synergy Test (DDST) based on β-lactam chelator combinations where EDTA/SMA has been used as an inhibitor and Imipenem, Ceftazidime as substrates. Results: 103 isolates which were identified as Escherichia coli spp, Klebsiella spp, Pseudomonas spp, Acinetobacter spp, Proteus spp, Providencia spp were found to be multidrug-resistant in antibiogram test. Isolates showed complete resistance (100%) to Imipenem, Meropenem, and Amoxiclav. The highest carbapenem-resistant etiological agents were Acinetobacter spp 40 (38.8%) followed by Pseudomonas spp 27 (26.2%), Klebsiella spp 26 (25.2%), Escherichia coli 8 (7.8%), Proteus spp 1 (1%) and Providencia spp 1 (1%). DPT method detected significantly (p = 0.000009) a higher number of MBL-producers (Imipenem with 0.5 M EDTA n = 61, 59.2% & Ceftazidime with 0.5 M EDTA n = 56, 54.4%) compared to the DDST method (Imipenem -0.5 M EDTA n = 43, 41.7%, Imipenem – SMA n = 38, 36.9% & Ceftazidime -0.5 M EDTA n = 15, 14.6%). Conclusion: Pieces of evidence suggest that DPT is a more sensitive method than DDST and could be recommended for identifying MBL-producing bacteria in Bangladeshi hospitals for the proper management of patients, to reduce time constraints and treatment costs. 展开更多
关键词 Disk Potentiation Test (dpt) Double Disk Synergy Test (DDST) Metallo-β-Lactamase (MBL) Sodium Mercaptoacetate (SMA) and Ethylenediaminetetraacetic Acid (EDTA)
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松辽盆地白垩系青山口组一段页岩生、排烃组分特征及页岩油相态演化
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作者 柳波 蒙启安 +7 位作者 付晓飞 林铁锋 白云风 田善思 张金友 姚瑶 程心阳 刘召 《石油与天然气地质》 EI CAS CSCD 北大核心 2024年第2期406-419,共14页
松辽盆地白垩系青山口组一段(青一段)页岩有机质热演化程度跨度大、烃类流动性差异强。页岩油相态分析预测是页岩油勘探开发的重要难题。用低成熟页岩样品开展封闭体系及半封闭体系有机质热解实验,根据生、排烃组分特征对滞留烃的轻烃... 松辽盆地白垩系青山口组一段(青一段)页岩有机质热演化程度跨度大、烃类流动性差异强。页岩油相态分析预测是页岩油勘探开发的重要难题。用低成熟页岩样品开展封闭体系及半封闭体系有机质热解实验,根据生、排烃组分特征对滞留烃的轻烃散失进行补偿校正,研究了页岩油组分演化特征。结合中央坳陷区主要生油凹陷典型井埋藏史、热演化史,研究了页岩油相态演化规律,提出了轻质页岩油勘探有利区和开发压力保护条件。研究结果表明:地质条件下随着有机质成熟度的升高,页岩油组分中轻质组分比例不断增加、气体逐渐增多,相包络线从高露点温度、低泡点压力依次向低露点温度、高泡点压力演化。齐家-古龙凹陷青一段页岩油在嫩江组中期油藏向挥发油油藏转化,长岭凹陷青一段页岩油从嫩江组末期开始油藏向挥发油油藏转化,三肇凹陷青一段页岩油则始终为黑油油藏。无论是黑油油藏还是挥发油油藏,均为单一液相。松辽盆地中央坳陷区青一段页岩油挥发油油藏主要分布在齐家-古龙凹陷中心和长岭凹陷北部有机质成熟度(镜质体反射率Ro)为1.3%~1.6%、地层压力为12.2~22.4 MPa的区域。 展开更多
关键词 轻烃补偿 相态动力学 露点温度 泡点压力 挥发油 页岩 青山口组一段 松辽盆地
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基于线性调频连续波的合作式通信辐射源测距
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作者 孙志国 赵旭 王震铎 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第3期496-503,共8页
针对加速运动目标参数估计中,离散多项式变换方法无法进行非整数估计的问题,本文提出基于瑞夫算法的离散多项式变换法和基于Chirp-Z变换的离散多项式变换法2种新型离散多项式变换算法,对加速运动目标速度和加速度进行估计,并对2种算法... 针对加速运动目标参数估计中,离散多项式变换方法无法进行非整数估计的问题,本文提出基于瑞夫算法的离散多项式变换法和基于Chirp-Z变换的离散多项式变换法2种新型离散多项式变换算法,对加速运动目标速度和加速度进行估计,并对2种算法的估计误差和计算量进行了分析比较。结果表明:2种算法在信噪比-20 dB时均方误差开始接近克拉美罗界。基于瑞夫算法的离散多项式变换法与3次迭代基于Chirp-Z变换的离散多项式变换法均可在较低信噪比下可实现任意频率的有效估计且性能接近,二者均可实现低信噪比下速度、加速度的有效估计,但基于瑞夫算法的离散多项式变换法计算量远小于3次迭代基于Chirp-Z变换的离散多项式变换法。 展开更多
关键词 线性调频信号 参数估计 多项式变换法 通信辐射源测距 加速度估计 速度估计 克拉美罗界 信噪比
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N_2O_5硝解DPT制备HMX 被引量:23
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作者 何志勇 罗军 +2 位作者 吕春绪 徐蓉 李金山 《火炸药学报》 EI CAS CSCD 北大核心 2010年第2期1-4,共4页
为了获得绿色硝化DPT制备HMX的工艺,研究了N2O5/HNO3和N2O5/有机溶剂两种硝化体系硝解DPT。在N2O5/有机溶剂体系中考察了不同溶剂对DPT的硝解,主要生成了低熔点的副产物,只有极少量的HMX生成,N2O5/有机溶剂体系不适合硝解DPT制备HMX。在... 为了获得绿色硝化DPT制备HMX的工艺,研究了N2O5/HNO3和N2O5/有机溶剂两种硝化体系硝解DPT。在N2O5/有机溶剂体系中考察了不同溶剂对DPT的硝解,主要生成了低熔点的副产物,只有极少量的HMX生成,N2O5/有机溶剂体系不适合硝解DPT制备HMX。在N2O5/HNO3体系中硝解DPT,考察了反应时间、反应温度、硝酸铵用量、反应料比等对HMX收率的影响。结果表明,随着N2O5用量的增加,HMX的收率呈现先增加后降低,在N2O5与DPT物质的量比为2、HNO3与DPT的物质的量比为36、反应时间30min、反应温度25℃的条件下,HMX收率可达58%,纯度99%,得出在N2O5/HNO3体系中硝解DPT能以较高收率制备HMX。 展开更多
关键词 有机化学 五氧化二氮 dpt HMX 硝解 绿色化学
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基于DPT的非线性调频信号参数估计 被引量:11
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作者 吕远 祝俊 唐斌 《电子测量与仪器学报》 CSCD 2009年第6期63-67,共5页
将非线性调频(NLFM)信号建模为高阶多项式相位信号(PPS)模型,采用由低阶离散多项式变换(DPT)到高阶DPT的逆向定阶方法确定模型阶数,并在此基础上,给出一种正弦调频信号(SFM)的DPT参数估计算法,可以实现对载波频率、调制频率及调频系数... 将非线性调频(NLFM)信号建模为高阶多项式相位信号(PPS)模型,采用由低阶离散多项式变换(DPT)到高阶DPT的逆向定阶方法确定模型阶数,并在此基础上,给出一种正弦调频信号(SFM)的DPT参数估计算法,可以实现对载波频率、调制频率及调频系数的估计。该算法不受调频系数范围的限制,核心环节为延时相关和FFT。仿真表明当SNR≥6dB时,调频参数的均方根误差小于-10dB。采用ADI公司TS201S芯片作为处理器,算法运行时间为3.30603ms,能够满足一般实时处理的要求。 展开更多
关键词 dpt NLFM PPS 判阶 SFM 参数估计
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DPT制备HMX工艺研究 被引量:15
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作者 李全良 陈军 王建龙 《含能材料》 EI CAS CSCD 2007年第5期509-510,共2页
以乌洛托品为起始原料,合成了中间体3,7-二硝基-1,3,5,7-四氮杂双环[3,3,1]壬烷(DPT),然后以氧化镁、硝酸铵、硝酸为硝解体系,硝解DPT制备出HMX。结果表明:在25℃的条件下,反应30 m in,收率达60.1%,工艺条件温和,易于控制,反应废液容易... 以乌洛托品为起始原料,合成了中间体3,7-二硝基-1,3,5,7-四氮杂双环[3,3,1]壬烷(DPT),然后以氧化镁、硝酸铵、硝酸为硝解体系,硝解DPT制备出HMX。结果表明:在25℃的条件下,反应30 m in,收率达60.1%,工艺条件温和,易于控制,反应废液容易处理。 展开更多
关键词 有机化学 硝胺类炸药 3 7-二硝基-1 3 5 7-四氮杂双环[3.3.1]壬烷(dpt) 制备 硝解
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铵离子对3,7-二硝基-1,3,5,7-四氮杂双环[3.3.1]壬烷(DPT)硝解反应影响(英文) 被引量:2
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作者 黄晓川 尉涛 +5 位作者 邱少君 郭涛 唐望 葛忠学 孟子晖 徐志斌 《含能材料》 EI CAS CSCD 北大核心 2015年第11期1151-1154,共4页
基于3,7-二硝基-1,3,5,7-四氮杂双环[3.3.1]壬烷(DPT)在HNO3-N H4N O3及HNO3中两种硝解机理,分别通过实验和理论计算方法对NH+4在DPT硝解反应中的作用进行了研究。将三种不同的铵盐(NH4)2H PO4,(NH4)2SO4和CH3C O O N H4添加到硝解体系... 基于3,7-二硝基-1,3,5,7-四氮杂双环[3.3.1]壬烷(DPT)在HNO3-N H4N O3及HNO3中两种硝解机理,分别通过实验和理论计算方法对NH+4在DPT硝解反应中的作用进行了研究。将三种不同的铵盐(NH4)2H PO4,(NH4)2SO4和CH3C O O N H4添加到硝解体系中,考察了NH+4对HM X产率的影响。结果表明,与NH4N O3的作用相似,以上三种铵盐可提高HM X产率,提高率分别为41.5%、37.4%和20.7%。在不同的HNO3-铵盐体系中,当N H+4与DPT的摩尔比接近10时,HM X的产率均达到最大值,分别为56.3%、52.2%和35.5%。对比了HNO3-铵盐和H N O3-硝酸盐体系中D PT硝解反应的结果,发现N H+4对HM X产率的提高起主导作用。采用密度泛函理论(DFT)对NH+4在DPT硝解反应过程中的作用机理进行了理论解释,得出HNO3/N H+4体系中D PT硝解反应的活化能为133.95 k J·m ol-1,低于HNO3体系中的376.73 k J·mol-1。 展开更多
关键词 1 3 5 7-四硝基-1 3 5 7-四氮杂环辛烷 3 7-二硝基-1 3 5 7-四氮杂双环[3.3.1]壬烷(dpt) 硝酸铵 硝化 密度泛函理论(DFT) 反应机理
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2,4,6-三硝基-2,4,6-三氮杂环己酮的合成Ⅱ以DPT或PHX为原料的合成 被引量:4
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作者 张跃军 《火炸药学报》 CAS CSCD 2001年第1期1-3,6,共4页
报道了以 DPT(或 PHX)与脲 (或硝基脲 )为原料在几种硝化剂中合成 2 ,4,6 -三硝基 - 2 ,4,6 -三氮杂环己酮 (RDX酮 )的方法 ,对由 DPT、PHX和 BSX这三种反应物的硝解碎片分子参加反应的形式和反应副产物的特点作了初步分析 ,结果表明 :... 报道了以 DPT(或 PHX)与脲 (或硝基脲 )为原料在几种硝化剂中合成 2 ,4,6 -三硝基 - 2 ,4,6 -三氮杂环己酮 (RDX酮 )的方法 ,对由 DPT、PHX和 BSX这三种反应物的硝解碎片分子参加反应的形式和反应副产物的特点作了初步分析 ,结果表明 :在硝解碎片中 ,非硝基取代的 N,N-二羟甲基胺类碎片分子参加了与脲 (或硝基脲 )的缩合反应 ,生成了产物 RDX酮 ,N,N-二羟甲基硝胺碎片分子不参加反应。以 DPT为原料时 ,RDX酮得率为 6 9% ,副产物为 HMX、RDX和小分子碎片 ;用 PHX作原料时 ,RDX酮得率最高达 36 % ,副产物为 HMX和小分子碎片 ;用 展开更多
关键词 2 4 6-三硝基-2 4 6-三氮杂环己酮 合成 dpt PHX 缩合反应 RDX酮
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康复治疗学专业DPT模式实训教学改革探索 被引量:4
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作者 王艳 李保龙 赵彬 《中国继续医学教育》 2021年第16期1-4,共4页
我国康复教育起步较晚,总体上缺乏办学经验和办学模式,在培养计划、课程设置、教学模式等方面没有成型的标准。康复治疗学专业是一门理论与实践并重的专业。学生毕业后是否具有基本专业技能和技术及其临床实践的实际操作能力,是衡量康... 我国康复教育起步较晚,总体上缺乏办学经验和办学模式,在培养计划、课程设置、教学模式等方面没有成型的标准。康复治疗学专业是一门理论与实践并重的专业。学生毕业后是否具有基本专业技能和技术及其临床实践的实际操作能力,是衡量康复治疗专业本科学生实践和临床能力水平的主要标准。实训教学是康复治疗学人才培养过程中极为重要的一环。为此,借鉴美国DPT教学模式,探索康复治疗学专业实训课程教学体系和教学方法,实现人才培养与社会需求的有效对接,形成符合康复治疗学专业高素质应用型专门人才培养的实训教学模式,以适应经济社会发展和医药卫生与健康事业改革需要。 展开更多
关键词 康复治疗学专业 人才培养 实训教学 dpt模式 教学改革 康复医学教育
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高渗葡萄糖增殖疗法治疗带状疱疹后遗神经痛的效果和安全性 被引量:2
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作者 殷琴 陈立平 +3 位作者 许恒 袁燕 梁栋 申文 《上海交通大学学报(医学版)》 CAS CSCD 北大核心 2024年第2期223-227,共5页
目的·探讨高渗葡萄糖增殖疗法(hypertonic dextrose prolotherapy,DPT)治疗带状疱疹后遗神经痛(postherpetic neuralgia,PHN)的效果和安全性。方法·选取2019年6月—2022年12月于徐州医科大学附属医院疼痛科就诊的PHN患者78例... 目的·探讨高渗葡萄糖增殖疗法(hypertonic dextrose prolotherapy,DPT)治疗带状疱疹后遗神经痛(postherpetic neuralgia,PHN)的效果和安全性。方法·选取2019年6月—2022年12月于徐州医科大学附属医院疼痛科就诊的PHN患者78例,将患者按照1∶1随机分配至对照组和研究组,每组各39例。对照组采用传统镇痛液治疗,研究组采用传统镇痛液联合DPT治疗。采用视觉模拟评分(visual analogue scale,VAS)评估患者治疗前后的疼痛程度,使用流式细胞仪测定患者T细胞亚群情况,使用酶联免疫吸附试验(enzyme-linked immunosorbent assay,ELISA)测定C反应蛋白(C-reactive protein,CRP)、白介素-6(interleukin-6,IL-6)及IL-10细胞因子水平。比较2组患者在治疗前,治疗后1、2、4、8及12周的VAS评分,治疗前和治疗2周后的CD4^(+)/CD8^(+)比值,CRP、IL-6、IL-10水平及不良反应发生情况。结果·2组患者的性别比例、年龄、病程差异无统计学意义。2组患者治疗后1、2、4、8及12周的疼痛评分均显著低于治疗前,差异均具有统计学意义(均P<0.05)。研究组治疗后1、2、4、8及12周的疼痛评分均显著低于对照组(均P<0.05)。2组患者治疗前CD4^(+)/CD8^(+)、CRP、IL-6及IL-10水平差异无统计学意义。治疗后研究组的IL-6、CRP水平低于对照组,差异有统计学意义(均P=0.000);治疗后研究组的CD4^(+)/CD8^(+)、IL-10水平高于对照组,差异具有统计学意义(均P=0.000)。2组患者在治疗过程中均未发生局部神经损伤、硬膜外血肿、感染、气胸、过敏等不良反应。结论·DPT可以明显缓解PHN患者疼痛,改善患者T淋巴细胞亚群和细胞因子表达,可安全应用于临床。 展开更多
关键词 高渗葡萄糖增殖疗法 带状疱疹后神经痛 T细胞计数 细胞因子
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风疹减毒活疫苗与DPT同时接种的免疫应答 被引量:2
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作者 徐福根 孟冬梅 +5 位作者 黄诚孝 陈康凯 许二萍 祝水芬 干伟群 凌国荣 《中国公共卫生学报》 1997年第6期344-344,共1页
为了解风疹减毒活疫苗与白百破疫苗(DPT)同时接种能否加重接种反应,我们进行了此项观察。现将结果报告如下。 材料与方法(1)分组与疫苗接种:以余杭市3个乡镇按时完成DPT基楚免疫的部分1岁儿童为观察对象,统一向其发接种通知.
关键词 风疹 风疹减毒活疫苗 dpt 接种 免疫应答
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微生物还原五价钒的电子传递过程及其钒还原对藻类生长的影响
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作者 王丽丽 周睿 +1 位作者 周雅琪 司友斌 《农业环境科学学报》 CAS CSCD 北大核心 2024年第3期516-526,共11页
为探究微生物还原五价钒[V(Ⅴ)]的机理,从钒污染土壤中筛选出一株V(Ⅴ)还原菌,经鉴定为神户肠杆菌(Enterobacter kobei NC1-2),研究不同电子传递抑制剂和电子穿梭体对菌株NC1-2还原V(Ⅴ)的电子传递过程的影响,以及V(Ⅴ)微生物还原前后... 为探究微生物还原五价钒[V(Ⅴ)]的机理,从钒污染土壤中筛选出一株V(Ⅴ)还原菌,经鉴定为神户肠杆菌(Enterobacter kobei NC1-2),研究不同电子传递抑制剂和电子穿梭体对菌株NC1-2还原V(Ⅴ)的电子传递过程的影响,以及V(Ⅴ)微生物还原前后的毒性变化及其对藻类生长的影响。结果表明,当V(Ⅴ)初始浓度20 mg·L^(-1),培养3 d时菌株NC1-2对V(Ⅴ)的还原率为90.3%。扫描电镜(SEM)结果显示菌株表面附着无定形物质,结合能量散射X射线谱(EDS)分析证实无定形物质中含有钒元素;X射线光电子能谱(XPS)分析表明菌株NC1-2将V(Ⅴ)还原为V(Ⅳ)。电子传递抑制剂辣椒素、奎那克林和氯化铜能抑制菌株NC1-2对V(Ⅴ)的还原;核黄素作为电子穿梭体可缩短电子传递距离,促进胞外电子传递,有利于V(Ⅴ)的还原,进而加快菌株NC1-2对V(Ⅴ)的还原。V(Ⅴ)还原成V(Ⅳ)后毒性降低,减少了对小球藻Chlorella pyrenoidosa和斜生栅藻Scenedesmus obliquus的生长胁迫,两种藻生长96 h时的藻密度显著增加,且叶绿素a含量均有所提高,分别为17.4 mg·L^(-1)和15.8 mg·L^(-1)。研究表明,强化微生物还原V(Ⅴ),能降低其对水生生物的毒性。 展开更多
关键词 五价钒 钒还原菌 电子传递 小球藻 斜生栅藻
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电子信息工程专业4DPT应用型人才培养模式研究 被引量:1
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作者 蒋强 祝加雄 +1 位作者 何都益 李敏 《乐山师范学院学报》 2019年第8期98-102,共5页
文章就提高电子信息工程专业应用型人才培养质量,更好地与企业行业接轨展开研究。针对二本院校应用型转型人才培养质量不高、与企业需求匹配度低的问题,提出了“4DPT”的培养模式。该模式以用人需求为导向,以教育部文件为指引,强调人才... 文章就提高电子信息工程专业应用型人才培养质量,更好地与企业行业接轨展开研究。针对二本院校应用型转型人才培养质量不高、与企业需求匹配度低的问题,提出了“4DPT”的培养模式。该模式以用人需求为导向,以教育部文件为指引,强调人才培养的过程性,提炼出企业生产一线对人才的要求、学校培养的目标体系、4DPT模式及课程实施四者间的内在联系,极具操作性。并经该专业实践,取得了较好的实效,为普遍提升电子信息工程专业人才培养质量起到了积极作用。 展开更多
关键词 电子信息工程 应用型 人才培养质量 4dpt 培养模式
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