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1.
New tin and thallium reagents capable of transferring the 1,2-di-tert-butylcyclopentadienyl moiety are easily prepared and utilized in furthering the transition metal organometallic chemistry of this intersting ligand. Lithium 1,2-di-tert-butylcyclopentadienide (1) reacts cleanly and selectively with SnClMe3 to give 2,3-di-tert-butyl-5-trimethylstannyl-1,3-cyclopentadiene (2), which in turn reacts with Re(CO)5Br to form the half-sandwich complex [Re(η5-C5H3(1,2-But)2)(CO)3] (3). The reaction between thallium ethoxide and 1,5-ditert-butyl-1,3-cyclopentadiene in hexane affords the excellent cyclopentadienyl transfer reagent, thallium 1,2-di-tert-butylcyclopentadienide (4). The thallium salt reacts with [Ru(COD)Cl2]n to give the sandwich complex [Ru(η5-C5H3(1,2-Bu2t)2)] (5).  相似文献   

2.
Formation of crystals in Schiff reagents prepared from SO2 gas previously has been reported either soon after preparation, using high dye concentrations and heating, or after long periods of storage at room temperature. With the first type of procedure only a low yield of crystals accompanied by dye precipitation was obtained. Crystallization without dye precipitation took place if the reagent, prepared with pararosaniline base or chloride in a saturated SO2 solution, was stored for a sufficient time at room temperature in partly filled flasks. These crystals remained colorless if washed with acid alcohol after being separated by filtration. Schiff reagents layered with paraffin oil or supplemented with 0.1 M hydroquinone took much longer to crystallize, suggesting that crystallizaticn is promoted by the partial oxidation of sulfurous acid to sulfuric acid. A high yield of crystals can be obtained at room temperature after as little as 24 hr by adding 0.04 M of H2SO4 to a Schiff reagent prepared with 2% pararosaniline chloride in a saturated SO2 solution. A Schiff reagent prepared with only 0.2% of these crystals gives an intense staining in the Feulgen and in the Periodic acid-Schiff reactions.  相似文献   

3.
Expression of beta2 microglobulin (beta2m) in Escherichia coli resulted in formation of inclusion bodies. Attenuated total reflectance Fourier transform infrared analysis suggested a native-like secondary structure of beta2m in the inclusion bodies. Nondenaturing solubilization of the native-like beta2m from inclusion bodies was achieved using L-arginine solution, which enables an efficient recovery of beta2m with little aggregation. Greater beta2m solubilization from inclusion bodies was obtained at higher temperatures. Low-temperature solubilization yielded beta2m with fluorescence properties identical to those of native beta2m, but its secondary structure was slightly nonnative. Solubilization at moderate temperature gave beta2m with an apparently native structure. We propose an efficient nondenaturing solubilization method combining L-arginine and moderate temperature.  相似文献   

4.
During the 1860’s, Hugo Schiff studied many reactions between amines and aldehydes, some of which have been used in histochemistry, at times without credit to Schiff. Much controversy has surrounded the chemical structures and reaction mechanisms of the compounds involved, but modern analytical techniques have clarified the picture. I review these reactions here. I used molecular modeling software to investigate dyes that contain primary amines representing eight chemical families. All dyes were known to perform satisfactorily for detecting aldehydes in tissue sections. The models verified the correct chemical structures at various points in their reactions and also determined how decolorization occurred in those with “leuco” forms. Decolorization in the presence of sulfurous acid can occur by either adduction or reduction depending on the dye. The final condensation product with aldehyde was determined to be either a C-sulfonic acid adduct on the carbonyl carbon atom or an aminal at the same atom. Based on the various outcomes, I have placed the dyes and their reactions into five categories. Because Hugo Schiff studied the reactions between aldehydes and amines with and without various acids or alcohol, it is only proper to call each of them Schiff reactions that used various types of Schiff reagents.  相似文献   

5.
目的:探讨裕泽毅血栓弹力图仪与美国血计公司TEG血栓弹力图仪检测结果相关性,可信度与优劣。方法:根据美国NCCLS-EP9-A,从我院随机抽取60例病人,分别取静脉血2ml、枸橼酸抗凝处理充分混匀后进行测定。用裕泽毅血栓弹力图仪与TEG血栓弹力图仪及两家公司生产的试剂进行平行交叉测定,观察其相关性。结果:美国血技公司TEG血栓弹力图仪对于两家公司的试剂检测结果高度相关(r0.8);裕泽毅公司血栓弹力图仪和试剂对于TEG血栓弹力图仪和试剂检测结果高度相关(r0.8)。结论:裕泽毅公司机器和试剂可以替代TEG机器和试剂进行血栓弹力图检测,能为临床医生提供可靠、准确、有价值的诊断指导依据。  相似文献   

6.
对国内6个厂家生产的人类免疫缺陷病毒(HIV-1/2)抗体酶标诊断试剂盒以不同人群标本进行特异性评价。经过筛查显示,我国抗HIV诊断试剂特异性检出约在8‰以内,阴性参比品特异性检测各试剂厂家约控制在5%以内。同时对国内外生产的试剂进行了比较  相似文献   

7.
表面活性剂对中性粒细胞的影响   总被引:1,自引:0,他引:1  
本文探讨了一种新的筛选血细胞作用试剂的方法。中性粒细胞经分离纯化后,表面活性剂对其作用效果可避免受到其他血细胞的影响,能准确反应表面活性剂的作用效果。此方法是筛选血细胞作用试剂的理想方法。  相似文献   

8.
A new fluorometric method for the determination of carbodiimides with trans-aconitic acid as a reagent has been developed. With the present method, as little as 50 pmol of carbodiimides can be determined. The relative standard deviations obtained with 25 nmol of dicyclohexylcarbodiimide (DCC), diisopropylcarbodiimide (DIC), and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide HCl (EDC) were 1.35, 1.41, and 2.72% (n = 10), respectively.  相似文献   

9.
组氨酸生产中间控制方法的研究   总被引:14,自引:0,他引:14  
研究了组氨酸与Pauly试剂显色反应的适宜条件 ,并加入钠盐和酪氨酸对标准曲线进行校正后 ,作为组氨酸定量测定的工作曲线。该方法简便 ,快速 ,准确度高 ,重现性好  相似文献   

10.
Selective fluorometric detection and determination of uranium ions is provided here using a novel fluorescent reagent, namely (E)-4-([4-hydroxynaphthalen-1-yl]diazenyl)-N-(5-methyleisoxazol-3-yl) benzenesulfonamide (UVI reagent). The UVI reagent offers a selective fluorescence enhancement behaviour at emission wavelength = 557 nm. The parameters affecting fluorometric detection of uranium ions, such as the pH, solvent type, ligand concentration, interaction time, and interfering ions, were investigated and adjusted. The proposed UVI reagent can detect and determine uranium ions even at low concentrations, for which the obtained limit of detection was 0.1 ppm. Additionally, this proposed determination protocol was successfully used to detect, monitor, and determine uranium ions in actual water samples.  相似文献   

11.
Monoclonal antibodies were obtained against all part of the body of the planarian Dugesia japonica japonica except tthe nerve cord, though parts of the enteric canal were also non reactive. The effect of a variety of fixatives (acetone, Bouin, formalin) used on planarian tissues prior to screening with antibodies, was assessed.  相似文献   

12.
用51%的Percoll分离液和DEAE-纤维素层析柱,从自然感染的黄鳝(Monopterus albusZuiew)中分离鳝锥虫(Trypanosoma monopteriChen et Hsieh,1964)。对含虫血液样品分别以2.1×103r/min、2.5×103r/min、2.9×103r/min、3.3×103r/min、3.6×103r/min离心5、10、15、20min,观察红细胞的去除和鳝锥虫存留百分数,结果表明:2.9×103r/min离心15min分离效果最佳。离心分离的混悬液含有锥虫、白细胞、血栓细胞和极少的红细胞,悬混液再经DEAE-纤维素过柱,得到纯净的鳝锥虫。过柱后光学显微镜观察,锥虫形态正常,运动活泼,无血细胞。本方法具有耗时短、回收率高的特点,是把梯度分离和离子交换结合在一起的一种快速有效方法,为鳝锥虫的进一步研究奠定了基础。另外,此方法还可以作为快速、准确检测自然状态下黄鳝是否感染锥虫的手段,为鳝锥虫的流行病学研究提供可靠的数据。  相似文献   

13.
A sensitive, specific, accurate and reproducible analytical method employing a divalent cation chelating agent (disodium EDTA) for sample treatment was developed to quantitate reserpine in FVB/N mouse plasma. Samples pretreated with 40 μl of 2% disodium EDTA in water were extracted by a semi-automated 96-well liquid–liquid extraction (LLE) procedure to isolate reserpine and a structural analog internal standard (I.S.), rescinnamine, from mouse plasma. The extracts were analyzed by turbo ionspray liquid chromatography–tandem mass spectrometry (LC–MS–MS) in the positive ion mode. Sample preparation time for conventional LLE was dramatically reduced by the semi-automated 96-well LLE approach. The assay demonstrated a lower limit of quantitation of 0.02 ng/ml using 0.1-ml plasma sample aliquots. The calibration curves were linear from 0.02 to 10 ng/ml for reserpine. The intra- and inter-assay precision of quality control (QC) samples ranged from 1.75 to 10.9% for reserpine. The intra- and inter-assay accuracy of QC samples ranged from −8.17 to 8.61%. Reserpine and the I.S. were found to be highly bound to FVB/N mouse plasma protein. This is the first report of disodium EDTA employed as a special protein-bound release agent to recover protein-bound analytes from plasma. These matrix effects and the effects of pH in the HPLC mobile phase on the sensitivities of LC–MS–MS are discussed in this paper.  相似文献   

14.
本文报告了国产乙型肝炎病毒(HBV)RIA和Abbott RIA诊断试剂盒检测质量的比较研究。表明两试剂滴定HBsAg、抗-HBs、抗-HBc阳性血清的敏感性相似,抗-HBs mIU/ml定量检测结果相符。证明国产RIA试剂质量是可靠的。但是,国产试剂S/N值曲线的陡度和标本的阳性检出率较Abbott试剂为高,可能与试剂出厂后周转期短有关。适当提高国产试剂阳性判定标准后,与Abbott试剂的检测符合率可达90%以上。  相似文献   

15.
为了提高血脂检验技术,探讨直接法测定低密度脂蛋白胆固醇(LDL-C),选用市售的两种直接测定LDL-C的试剂盒进行方法学的实验评价,结果表明:直接法具有简便、快速、准确和适合自动分析等特点.两种试剂盒的测定结果都能满足建立分析方法要求的目标,不精密度<4%,两法显著相关r=0.994, y=1.0572x-0.1052, Sy/x=0.1913,且各种方法学检验结果相近,使用者可结合实际选作常规测定之用.  相似文献   

16.
In view of its probable wide applicability, it seems desirable to publish a note on a simple technic for the recognition with the microscope of the action of lipase. In brief, the method is to make an emulsion of neutral fat previously stained with a red Sudan stain, subject some of the emulsion to the action of the supposed lipase for an appropriate time and then examine with the microscope a recovered drop of the emulsion in a solution of Nile blue sulfate. It has long been known that Nile blue sulfate stains liquid neutral fats a reddish color and fatty acids blue.  相似文献   

17.
制备一种精确的破伤风抗体定量试剂,用于人源破伤风抗体的定量及人群破伤风抗体水平的测定。以人源破伤风免疫球蛋白国家标准品建立定量反应曲线,经系统优化后建立双抗原夹心法定量检测系统。定量反应曲线显示,抗体浓度在10~120m IU/m l之间,相关系数r=0.9993。精密度(CV)≤7%。实际应用验证,未经(TTC)免疫的献血员中,具有保护性抗体水平(0.01 IU/m l)的比例只占12.2%。经3针(TTC)免疫后,抗体水平均大于0.01 IU/m l,经动物体内中和试验法(NT)定量的3批破伤风免疫球蛋白,用制备的酶联免疫破伤风抗体定量试剂测定,其回收率分别为109%、98%和93%。结论,该试剂可用于破伤风抗体的精确定量。  相似文献   

18.
薄层层析法在生物化学实验中的改进   总被引:1,自引:0,他引:1  
对脂类的薄层层析进行改进,用碘蒸气显色代替磷钼酸显色,脂类层析时间、斑点展开距离及显色结果令人满意。改进后的显色方法简便、快速、效果好,便于学生实验操作。  相似文献   

19.
PIG-B: A homemade monophasic cocktail for the extraction of RNA   总被引:2,自引:0,他引:2  
An inexpensive monophasic reagent has been developed for the extraction of total RNA from cells or tissues. The main ingredients of the reagent arePhenol,Isoamyl alcohol,Guanidinium isothiocyanate, andBeta-mercaptoethanol (PIG-B). The quality and yield of RNA obtained by this reagent is at par with that obtained by TRIzol, an expensive but widely used monophasic reagent available commercially. The complete composition and method of preparation of PIG-B is provided to aid preparation of the reagent in the laboratory.  相似文献   

20.
DNA疫苗的细菌内毒素检测   总被引:7,自引:0,他引:7  
目的 :考察DNA疫苗细菌内毒素的检查方法的可行性及DNA疫苗的干扰作用。方法 :干扰试验和对比试验。结果 :供试品阴性对照系列样品溶液无干扰作用 ,与家兔法结果一致。结论 :将疫苗稀释 2倍可用灵敏度为 0 5EU ml的鲎试剂作细菌内毒素检查。  相似文献   

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