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81.
82.
Synthesis and selective cleavage of oligodeoxyribonucleotides containing non-chiral internucleotide phosphoramidate linkages. 总被引:3,自引:3,他引:0 下载免费PDF全文
Oligodeoxynucleotides containing phosphoramidate internucleotide links 3'-OP(O)NH-5' have been prepared using standard solid phase phosphoramidite techniques. For the incorporation of the phosphoramidate linkages we have used monomer as well as dimer building blocks. With the monomer 3'-phosphoramidite building blocks, which are derived from 5'-amino-2',5'-dideoxynucleosides, it is possible to incorporate phosphoramidate links into specific positions within an oligodeoxynucleotide. Furthermore the synthesis of several dinucleoside phosphate derivatives which are linked by phosphoramidate bonds are described. The internucleotide phosphoramidate linkage was performed using the Staudinger reaction followed by a Michaelis-Arbuzov type transformation. After 3'-phosphitylation these dinucleosides are compatible with the current phosphoramidite methodology of oligodeoxynucleotide synthesis. 相似文献
83.
Extraoocytäre Komponenten des Eiwachstums beiApis Mellifica 总被引:1,自引:0,他引:1
Wolf Engels 《Insectes Sociaux》1968,15(3):271-288
84.
A Stable Genomic Source of P Element Transposase in Drosophila Melanogaster 总被引:133,自引:56,他引:77 下载免费PDF全文
H. M. Robertson C. R. Preston R. W. Phillis D. M. Johnson-Schlitz W. K. Benz W. R. Engels 《Genetics》1988,118(3):461-470
A single P element insert in Drosophila melanogaster, called P[ry+ delta 2-3](99B), is described that caused mobilization of other elements at unusually high frequencies, yet is itself remarkably stable. Its transposase activity is higher than that of an entire P strain, but it rarely undergoes internal deletion, excision or transposition. This element was constructed by F. Laski, D. Rio and G. Rubin for other purposes, but we have found it to be useful for experiments involving P elements. We demonstrate that together with a chromosome bearing numerous nonautonomous elements it can be used for P element mutagenesis. It can also substitute efficiently for "helper" plasmids in P element mediated transformation, and can be used to move transformed elements around the genome. 相似文献
85.
John A. Sved Leila M. Blackman A. Stuart Gilchrist William R. Engels 《Molecular & general genetics : MGG》1991,225(3):443-447
Summary P element transposons in Drosophila melanogaster are capable of mobilizing incomplete P elements elsewhere in the genome, and of inducing recombination. This recombination is usually only of the order of 1% or less. We show that two P elements, located at exactly homologous sites, induce levels of recombination of 20% or higher. The recombination appears to be exact, as determined by the lack of phenotypic effects in recombinant products and the lack of size changes detectable by Southern hybridization. Female recombination is increased, but to a lesser extent than male recombination. Somatic recombination levels are also elevated. Alternative explanations for the high recombination levels are given in terms of the consequences of repair of an excision site and in terms of recombination as part of the replicative transposition process. 相似文献
86.
Synthesis of 5′-Ethynyl-2′-deoxynucleoside Analogues as Building Block for Antisense Oligonucleotide
Hassan B. Lazrek Abdelalli Rochdi Joachim W. Engels 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1257-1259
Abstract New nucleosides and nucleoside analogue dimers were prepared using 5′-ethynyl-2′-deoxynucleoside as starting material. 相似文献
87.
Abstract In general there are three different ways in which eucaryotic genes can be expressed in E. coli. 相似文献
88.
Olga Frolow Bela E. Bode Joachim W. Engels 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):655-659
For EPR measurements of RNA, DNA, or proteins, the occurrence of the paramagnetic species is necessary. The aim of this work is to improve the synthesis of two different EPR spinlabels 2,2,6,6-tetra methyl-3,4-dehydro-piperidin-N-oxyl-4-acetylene (TEMPA) 6 and 15N-labeled TEMPA 6* and their coupling to uridine. The yield of the synthesis of TEMPA could be increased to 40% and the second nitroxide 2,2,6,6-tetramethyl-3,4-dehydro-piperidin-15N-oxyl-4-acetylene 6* could be synthesized with a yield of 11%. 相似文献
89.
Ohne ZusammenfassungMit Unterstützung durch die Deutsche Forschungsgemeinschaft 相似文献
90.
Marianne Engels Claire Michael Katalin Dobra Anders Hjerpe Ambrogio Fassina Pinar Firat 《Cytopathology》2019,30(1):31-38
Serous effusion fluid is one of the most commonly encountered specimens in routine cytopathology practice. It provides invaluable information about the patient and the clinical status; but to get the most of it, specimen handling and processing must be carried out properly. Cytomorphology is the basis of a successful analysis which should complemented by ancillary tests when needed. A wide spectrum of ancillary techniques ‐ ranging from immunocytochemistry and flow cytometry to different assays of molecular pathology ‐ can be applied to serous effusions. This article describes the acquisition and management of serous effusion fluids, methods for preservation and transportation, different techniques of cytopreparation, application of immunocytochemistry, flow cytometry, and fluorescence in‐situ hybridization (FISH), as well as DNA extraction for polymerase chain reaction (PCR) and next generation sequencing (NGS). Principles of bio‐banking of effusion samples are also discussed which is getting more important in correlation with the developments in personalized medicine. 相似文献