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91.
A Stable Genomic Source of P Element Transposase in Drosophila Melanogaster 总被引:133,自引:56,他引:77
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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
92.
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
93.
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
94.
Abstract In general there are three different ways in which eucaryotic genes can be expressed in E. coli. 相似文献
95.
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
96.
Ohne ZusammenfassungMit Unterstützung durch die Deutsche Forschungsgemeinschaft 相似文献
97.
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
98.
Stein C Kuchenmüller T Hendrickx S Prüss-Ustün A Wolfson L Engels D Schlundt J 《PLoS neglected tropical diseases》2007,1(3):e161
The Global Burden of Disease (GBD) concept has been used by the World Health Organization (WHO) for its reporting on health information for nearly 10 years. The GBD approach results in a single summary measure of morbidity, disability, and mortality, the so-called disability-adjusted life year (DALY). To ensure transparency and objectivity in the derivation of health information, WHO has been urged to use reference groups of external experts to estimate burden of disease. Under the leadership and coordination of WHO, expert groups have been appraising and abstracting burden of disease information. Examples include the Child Health Epidemiology Reference Group (CHERG), the Malaria Monitoring and Evaluation Reference Group (MERG), and the recently established Foodborne Disease Burden Epidemiology Reference Group (FERG). The structure and functioning of and lessons learnt by these groups are described in this paper. External WHO expert groups have provided independent scientific health information while operating under considerable differences in structure and functioning. Although it is not appropriate to devise a single "best practice" model, the common thread described by all groups is the necessity of WHO's leadership and coordination to ensure the provision and dissemination of health information that is to be globally accepted and valued. 相似文献
99.
100.
Guallar-Castillón P Sagardui-Villamor J Banegas JR Graciani A Fornés NS López García E Rodríguez-Artalejo F 《Obesity (Silver Spring, Md.)》2007,15(1):233-244
Objective: Few studies have addressed the association between abdominal obesity, as measured by waist circumference (WC), and disability in the elderly. Moreover, those studies were cross‐sectional and yielded inconsistent results. The objective of this study was to examine longitudinally the association between WC and self‐reported disability among older adults. Research Methods and Procedures: A prospective cohort study was conducted from 2001 to 2003 in 3235 persons (1411 men and 1824 women) representative of the non‐institutionalized Spanish population ages 60 years and older. Baseline information was collected by home‐based personal interviews and measurement of WC, weight, and height. Two years later, information on disability was obtained by telephone interview. The association of interest was summarized with odds ratios obtained by logistic regression. Results: Among persons reporting no disability at baseline, WC predicted disability 2 years later. After adjustment for age, education, tobacco use, alcohol consumption, and physical activity, men in the highest WC quintile had 2.17 (95% confidence interval, 1.15 to 4.09) times more risk of mobility disability and 4.77 (95% confidence interval, 2.50 to 9.13) times more risk of agility disability than those in the lowest quintile. Additional adjustment for BMI, chronic diseases, and cognitive function led to only a slight reduction in this association. Results were similar for women. No statistically significant association was observed between WC and restriction of daily activities, limitation in instrumental activities of daily living, and limitation in bathing or dressing, in either men or women. Discussion: WC predicts mobility and agility disability in old age. Avoidance of the highest values of WC might decrease the risk of disability in older adults. 相似文献