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121.
The synthesis of phosphoramidite reagents and solid-phase supports based on hydroxyprolinol for the introduction of the residues of biotin, lipoic acid, amino groups, and terminal acetylene groups at different positions of the oligonucleotide chain has been described. The efficiency of the reagents and supports has been confirmed by the synthesis of the corresponding modified oligonucleotides.  相似文献   
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栖息地的减缩和破坏是野生动物种群衰退重要因素之一,尤对那些小型且不为人们注意、目前仍属非经济动物种类,其栖息地的减缩和破坏更是最重要原因。对这种现象,有识之士都在大声疾呼:保护生物多样性,保护人类赖以生存的地球。近年来国外对动物园的功能提出了许多新的...  相似文献   
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Abstract:  Four new genera and species of annelid, Hunsrueckochaeta hohensteini , Ewaldips feyi , Crocancistrius lutzi and Scopyrites magnus , are described from the Hunsrück Slate (Lower Emsian) of Germany, as well as new material of Bundenbachochaeta eschenbachensis   Bartels and Blind, 1995 . The specimens preserve details of the appendages and other aspects of the morphology as a result of pyritization. A phylogenetic analysis using the morphological data matrix of Rouse and Fauchald places four of the five genera basal to the Aciculata; the fifth Ewaldips falls within the Scolecida. The diversity of annelids represented in the Hunsrück Slate is similar to that in the other major Palaeozoic Konservat-Lagerstätten that yield them, including the Cambrian Burgess Shale and the Late Carboniferous Mazon Creek biota.  相似文献   
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Abstract: Lower Ordovician faunas of Bohemia (Perunica), Baltica and North China include the oldest known representatives of the Order Craniida, but otherwise in Gondwana and associated terranes, the record of craniides is sparse. Pseudocrania insperata sp. nov. from the Lashkarak Formation of the Eastern Alborz Mountains is the first and as yet only record of the occurrence of craniides in the Middle Ordovician (Darriwilian) of Iran and temperate to high latitude peri‐Gondwana. Pseudocrania was known hitherto only from the Middle Ordovician of Baltoscandia and the Chu‐Ili terrane of Kazakhstan.  相似文献   
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THE BOOK CORNER     
In order to increase the yield of prothrombin complex concentrates (PCCs) and to reduce their associated thrombotic risks, the influence of washing conditions on the yield, purity, and balance of coagulation factors (FII, FVII, FIX, and FX), and inhibitor proteins (PC, PS, PZ, and AT [antithrombin]) in PCCs was investigated by orthogonal testing, in which three variables (sodium citrate, NaCl, and pH) and their three levels were selected. It was found that AT yield and purity were extraordinarily low, and at lower NaCl content, the general yield, purity, and balance were higher, lower, and better, respectively; however, the results became contrary at higher NaCl. Moreover, within the investigated levels, NaCl was the first determinant for the yield except AT and the purity except FVII, PC, PS, and AT. Sodium citrate was the first determinant for AT yield and FVII, PS, and AT purity. The yield except FII, PS, and AT decreased and the purity except PC increased with increase of sodium citrate content. Just for PC purity, pH was the first determinant. The effect with pH fluctuation on the yield and purity was characteristically unobvious. The outcome undoubtedly supplies the guidance to further improve PCCs.  相似文献   
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