排序方式: 共有69条查询结果,搜索用时 15 毫秒
41.
Li D Ren W Wang X Wang F Gao Y Ning Q Han Y Song T Lu S 《Applied biochemistry and biotechnology》2009,158(2):253-261
To establish an economical and reproducible method for the high-quality RNA extraction from pancreas, we isolated total RNA from rat pancreas with TRIzol reagent and liquid nitrogen. In the initial stage, we optimized three influential factors, the way to homogenize pancreas, the time to collect the pancreatic tissue from animals, and the weight of the pancreatic tissue in 1 ml of TRIzol reagent. The RNA quality was determined by detecting total RNA content and its absorbance at 260/280 nm wavelength, visualizing RNA in non-denatured agarose gel and performing RT-PCR of pancreas-specific genes. The A (260)/A (280) ratio of the total RNA extracted by grinding 20-30 mg of rat pancreatic tissue removed from the rats in liquid nitrogen within 1 min and then immersed in 1 ml of the TRIzol Reagent was 1.75-1.89, and the ratio of 28S/18S ribosomal RNA bands was more than 1.8. Furthermore, full length of Pdx1 open-reading frame was amplified with RNA extracted from the grinding group rather than from the conventional group. The RT-PCR products of pancreas-specific genes from both exocrine and endocrine parts of pancreas were successfully derived from the extracted RNA. The results suggested that we successfully provided an economical, fast, and reproducible method to obtain the high-quality and intact RNA from rat pancreas with TRIzol Reagent and liquid nitrogen. 相似文献
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DNA芯片的制备方法主要有离片合成法和在片合成法.离片合成是用点样法将DNA探针固定在基片上;在片合成是在基片表面直接原位合成寡核苷酸探针阵列.目前国外已有多种DNA芯片原位合成方法的报道,但其中仅Fordor等提出的光脱保护DNA固相原位合成技术已商品化,该方法制备成本高, 相似文献
43.
Mongi Ben Mosbah Hanen Chouaib Mohamed Kossentini Mansour Salem 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1433-1440
Thionyl chloride 2 and Lawesson Reagent (L.R.) 4 react with N 1 -tosylamidrazones 1 to give respectively 1-oxyde-1,2,3,5-thiatriazole 3 and triazaphospholines 5 derivatives. The structure of products 3 and 5 is confirmed by IR and NMR spectroscopy. 相似文献
44.
A technique for determination of enantiomeric excess of cathinone, 2-amino-1-phenyl-1-propanone, by use of the chiral lanthanide shift reagent (LSR), tris[3-(heptafluoropropylhydroxymethylene)-d-camphorato]europium (III), Eu (HFC)3, is described. The hydrochloride salt of the cathinone sample is first converted directly to the N-acetyl derivative without need for isolation of the potentially unstable cathinone free base. Addition of Eu (HFC)3 to the crude acetylated cathinone resulted in near-baseline resolution of the CH 3CO resonances of the enantiomers. Analytical utility and the sense of magnetic nonequivalence of this signal were demonstrated using “spiked” non-racemic samples. 相似文献
45.
Mohamed Boukraa Mohamed Lotfi El Efrit Hédi Zantour 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):145-152
Abstract The Lawesson Reagent (L.R) 1 reacts with hydrazonates 2 and hydroxymates 3 to give 1,3,4,2-thiadiazaphospholines 4 and 1,3,5,2-oxathiazaphospholines 5 derivatives. The structure of products 4 and 5 is confirmed by IR and NMR spectroscopy. 相似文献
46.
Guoxiong Hua 《Tetrahedron letters》2007,48(21):3677-3679
Woollins’ reagent (WR) acts as a deoxygenation reagent for a wide range of sulfoxides affording the corresponding sulfides in good to excellent yields (up to 99% isolated yield) under mild conditions. 相似文献
47.
Jayanta Dey Nayan Banerjee Swikriti Daw Prof. Joyram Guin 《Angewandte Chemie (International ed. in English)》2023,62(44):e202312384
Utilization of oxime ethers as bifunctional reagents remains unknown. Herein, we present a mechanistically distinct strategy that enables oximesulfonylation of olefins using sulfonyl-oxime-ethers as bifunctional reagents under metal-free photochemical conditions. Via concomitant C−S and C−C bond formation, the process permits incorporation of oxime and sulfonyl groups into olefins in a complete atom-economic fashion, providing rapid access to multi-functionalized β-sulfonyl oxime ethers with good yields and stereoselectivity. The method is amenable to functionalization of complex bioactive molecules and is shown to be scalable. A radical chain mechanism initiated via photochemical Hydrogen Atom Transfer (HAT) mediated N−O bond cleavage is suggested for the process, based on our results on mechanistic investigations. 相似文献
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11NTRODUCTIoNThederivativesofdiazaphospholidinoneorthecorrespondingthionesareknowntopossessinterestingbiologicalproperties,suchasherbicidalactivity"'2i.Inrecentyears,itwasreportedthatthel,4,2-diazaphospholindine-5-thione-2havegoodselectiveherbicidalactivity"'41.Tolookformoreeffectiveherbicideswithlowtoxicity,aseriesofnovel1-(o-methylphenyl)-2-(p-methoxyphenyl)-phospholidin-4-thione-sulfideshavebeensynthesizedandtheirmolecularstructuresstudied.PreliminarybioassaysshowthatthesecomPoundshaveg… 相似文献
50.
Mild and efficient method for bromination of electron-rich aromatic compounds is described using polyvinylpolypyrrolidone-bromine complex(PVPP-Br2).The reaction proceeded smoothly with phenols and N,N-alkylated amines to afford the corresponding monobrominated product in good yields at ambient temperature. 相似文献