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1.
甲磺酸伊马替尼的合成   总被引:3,自引:0,他引:3  
以4-甲基-3-硝基苯胺为起始原料,经过缩合、还原、环合等反应制得抗肿瘤药物甲磺酸伊马替尼。并分别讨论了采用无水碳酸钾代替二异丙基乙胺、水合肼和普通催化剂代替铂炭催化剂以及采用异戊醇作为溶剂的优点。最终反应总收率超过50%,用高效液相色谱分析产品纯度在99.5%以上。  相似文献   
2.
针对原有工艺条件的操作条件苛刻和反应原料贵的缺点,设计并实施了一种制备2,2-二异丙基丙腈的方法.首先,在吡啶的存在下,甲磺酰氯与异丙醇缩合制备异丙基甲磺酸酯.不经分离,直接与丙腈反应,在氨基钠的作用下发生缩合反应,合成得到2,2-二异丙基丙腈,总收率81.3%,含量98%.结果表明:能有效通过改变起始原料和工艺过程,使得原料易得,操作条件温和,更好地满足工业化生产要求,具有潜在的工业化价值.  相似文献   
3.
Tricaine mesylate (MS-222) is one of the most used anesthetics in fish. It can be absorbed by the human body via food consumption, with related detriments to human health. In this study, a modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) method was developed for the determination of MS-222 in carp muscle and water samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS). For cleanup procedure, multiplug filtration cleanup (m-PFC) method with n-Hexane delipidation was adopted. The extraction solvent, cleanup methods and sorbents were optimized. All method validation parameters were in the acceptable range. The dissipation behavior study was followed by the method development. Firstly, the anesthesia dose and time were optimized in application study. Secondly, carps were revived for different period of time with (experimental group) and without (control group) the oxygenation aeration treatment to compare the dissipation rate of MS-222. After being anesthetized for 6 h at 50 mg/L and 12 h of elimination, the concentrations of MS-222 in crap muscle and water of experimental group was lower than those of control group. After 36 h of elimination under oxygenation aeration, over 90% of MS-222 was dissipated in carp muscle. The results showed that the half-life of MS-222 in carp muscle was 6.2 h. The findings suggested that the commonly-used oxygenation aeration treatment in aquaculture production had potential effects in accelerating the dissipation of MS-222 in carp and water. In this study, three days of withdrawal period was recommended in carps after MS-222 administration under oxygenation aeration.  相似文献   
4.
根据甲磺酸培氟沙星能与茜素红在KH2PO4-Na2HPO4缓冲溶液中发生反应生成稳定的电荷转移配合物,建立了用分光光度法测定甲磺酸培氟沙星的简便快速的新方法.在所选定的最佳条件下,甲磺酸培氟沙星的浓度在10.0~200.0 mg/L范围内符合比尔定律,相关系数r=0.995,方法检测限为5.46 mg/L,对样品平行测定10次的相对标准偏差为3.1%,回收率在94.0%~103.1%之间.该法可用于片剂中甲磺酸培氟沙星含量的测定.  相似文献   
5.
为了确定大口黑鲈成鱼适合的麻醉方式和麻醉剂量,研究了不同浓度的丁香酚和MS-222对大口黑鲈的静水麻醉效果。在最适麻醉质量浓度下模拟运输24 h,记录24 h存活率并测定麻醉0.5、4、8、16和24 h后的血清生化指标、水质p H、氨氮以及麻醉剂的残留量。结果表明:随着丁香酚和MS-222浓度增加,入麻时间缩短,复苏时间延长;丁香酚和MS-222的最适质量浓度分别为18~20 mg/L、50~60 mg/L时,两麻醉组模拟运输和复苏24 h后的成活率为100%,显著高于无麻醉运输组的80%和90%(p<0.05);随着麻醉时间延长,丁香酚和MS-222组血清中的皮质醇(COR)分别从336.83pg/m L下降到291.41pg/m L,从286.11上升到367.05pg/m L(p<0.05),丁香酚组血清中的COR显著低于对照组;葡萄糖分别从14.36、7.48 mg/dL下降到7.36、3.11 mg/dL(p<0.05),而丁香酚组中乳酸脱氢酶(LDH)、碱性磷酸酶(AKP)、谷草转氨酶(GOT)、尿素氮(BUN)的浓度显著低于MS-222组(p<0.05);残留检测结果表明在麻醉0.5h时,鱼肉中丁香酚含量达到最大值5.14mg/kg,在清水中复苏1d时丁香酚残留量为0.45mg/kg;而MS-222组在8 h残留量达到最大值为36.24 mg/kg,复苏4 d时基本消除完全。结果显示,丁香酚剂量小,代谢快,在诱发氧化应激和组织损伤时有较少的副作用。  相似文献   
6.
朱盈蕊  高向阳  王珊  陈双  张小燕 《食品科学》2012,33(22):246-249
建立了一种快速测定动物肝脏中甲磺酸达氟沙星的新方法。本方法的基础是碱性介质中甲磺酸达氟沙星对鲁米诺-高碘酸钾体系发光强度的线性增敏作用,样品通过固相萃取柱净化后,在与标准曲线完全相同的条件下用流动注射化学发光法测定。结果表明:优化实验条件下,甲磺酸达氟沙星在质量浓度4.53×10-6~2.27×10-3mg/mL范围内与体系相对化学发光强度呈良好线性关系,检出限为3.76×10-6mg/mL,相对标准偏差RSD为1.9%(n=11)。用于猪肝和鸡肝甲磺酸达氟沙星的测定,加标回收率为69.00%~97.50%,结果令人满意。  相似文献   
7.
目的:建立高效液相色谱法测定甲磺酸伊马替尼片有关物质的方法。方法:色谱柱为KromasilCl8(250mm×4.6mm,5肛m),以含0.04%辛烷磺酸钠的20mmol/L磷酸二氢钠溶液(磷酸调至PH2.5)-甲醇为流动相,梯度洗脱,流速为1ml.min-1,检测波长为268nm,柱温为30℃。结果:在本方法中,甲磺酸伊马替尼的线性关系良好,r为0.9999;专属性强,甲磺酸伊马替尼与各中间体及各降解产物之间都能完全分离;精密度良好,RSD为1%。结论:该方法准确、简便、灵敏,可用于甲磺酸伊马替尼片有关物质测定。  相似文献   
8.
Compatibility between a hydrophilic nanoclay reinforcement and organophilic polymer matrix resin is achieved by ion exchange reaction substitution of intra gallery mono- or divalent cation with foreign aliphatic long-chain cation. The exchange of long-chain cation increases the organophilicity of the clay layers and provides sufficient layer separation for polymer chains to impregnate into the formation of a nanocomposite. This study demonstrates the synthesis of hydroxy functional longchain amine hydrochloride from Vernonia galamensis oil (VO). Vernonia galamensis oil, containing a naturally epoxidized long-chain TG, was transesterified under basic conditions to yield VO methyl esters (VOMe). The VOMe were reduced using lithium aluminum hydride (LAH) in hexane to obtain cis-12,13-epoxy-cis-9-octadecenol (vernanol) as the primary product. Vernanol was then converted to vernanyl mesylate, followed by reaction with potassium cyanide to obtain cis-13,14-epoxy-cis-10-nonadecenitrile (C19 nitrile). The C19 nitrile was reduced with LAH in diethyl ether medium and later reacted with hydrochloric acid to obtain the title product. 1H and 13C NMR, FTIR, and matrixassisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) techniques were used to characterize the intermediates and the title product.  相似文献   
9.
The ability of brown seaweed extracts, Ascophyllum nodosum, Laminaria hyperborea, Pelvetia canaliculata, Fucus vesiculosus and Fucus serratus to protect against tert-butyl hydroperoxide (tert-BOOH) induced stress in Caco-2 cells was investigated. Oxidative stress was determined by measuring alteration in the enzymatic activity of catalase (CAT) and superoxide dismutases (SOD) and cellular levels of glutathione (GSH). L. hyperborea, P. canaliculata and F. serratus significantly protected against tert-BOOH induced SOD reduction but did not protect against the reduction in CAT activity or the increased cellular levels of GSH. The ability of F. serratus and F. vesiculosus to protect against H2O2 and tert-BOOH induced DNA damage was also assessed. The DNA protective effects of the two seaweed extracts was compared to those of three metal chelators; deferoxamine mesylate (DFO), 1,10-phenanthroline (o-phen) and 1,2-Bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid tetrakis (BAPTA-AM). F. serratus and F. vesiculosus significantly protected (P < 0.05) against H2O2 (50 μM) induced DNA damage but not tert-BOOH induced damage.  相似文献   
10.
We explored the mechanism of cell death of the polymethoxyflavone tangeretin (TAN) in K562 breakpoint cluster region‐abelson murine leukemia (Bcr‐Abl+) cells. Flow cytometric analysis showed that TAN arrested the cells in the G2/M phase and stimulated an accumulation of the cells in the sub‐G0 phase. TAN‐induced cell death was evidenced by poly(ADP)‐ribose polymerase cleavage, DNA laddering fragmentation, activation of the caspase cascade and downregulation of the antiapoptotic proteins Mcl‐1 and Bcl‐xL. Pretreatment with the pancaspase inhibitor Z‐VAD‐FMK_blocked caspase activation and cell cycle arrest but did not inhibit apoptosis which suggest that other cell killing mechanisms like endoplasmic reticulum (ER)‐associated cell death pathways could be involved. We demonstrated that TAN‐induced apoptosis was preceded by a rapid activation of the proapoptotic arm of the unfolded protein response, namely PKR‐like ER kinase. This was accompanied by enhanced levels of glucose‐regulated protein of 78 kDa and of spliced X‐box binding protein 1. Furthermore, TAN sensitized K562 cells to the cell killing effects of imatinib via an apoptotic mechanism. In conclusion, our results suggest that TAN is able to induce apoptosis in Bcr‐Abl+ cells via cell cycle arrest and the induction of the unfolded protein response, and has synergistic cytotoxicity with imatinib.  相似文献   
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