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排序方式: 共有1832条查询结果,搜索用时 31 毫秒
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D Cassidy-Hanley J Bowen JH Lee E Cole LA VerPlank J Gaertig MA Gorovsky PJ Bruns 《Canadian Metallurgical Quarterly》1997,146(1):135-147
Mating Tetrahymena thermophila were bombarded with ribosomal DNA-coated particles at various times in development. Both macronuclear and micronuclear transformants were recovered. Optimal developmental stages for transformation occurred during meiosis for the micronucleus and during anlagen formation for the macronucleus. Evidence is given for transient retention of the introduced plasmid. Genetic and molecular tests confirmed that sexually heritable transformation was associated with integration at the homologous site in the recipient micronuclear chromosome. 相似文献
186.
Zusammenfassung Personenbezogene Daten müssen gel?scht werden, wenn sie für die weiteren Gesch?ftprozesse der Unternehmen nicht mehr erforderlich
sind und auch gesetzliche Aufbewahrungsfristen der L?schung nicht im Wege stehen. In der Praxis wird dieser L?schpflicht allerdings
nur zurückhaltend Rechnung getragen. Der Beitrag begründet das Erfordernis konsequenten L?schens und will dazu motivieren,
den gesetzlich vorgegebenen L?schpflichten durch ein L?schkonzept Rechnung zu tragen.
Reinhard Fraenkel ist nach verschiedenen T?tigkeiten in der Industrie seit 1994 als Rechtsanwalt in Gütersloh t?tig. Zu seinen
Arbeitsschwerpunkten z?hlt das Datenschutzrecht. Seit August 2004 ist er externer Datenschutzbeauftragter der Toll Collect
GmbH.
Dr. Volker Hammer ist Consultant der Secorvo GmbH. Seit Mitte 2003 unterstützt er die Toll Collect GmbH in verschiedenen Datenschutz-Projekten.
Weitere Arbeitsschwerpunkte sind Public Key Infrastrukturen und kritische IT-Infrastrukturen 相似文献
187.
David Rafaja Milan Dopita Magsud Masimov Volker Klemm Nina Wendt Walter Lengauer 《International Journal of Refractory Metals and Hard Materials》2008,26(3):263-275
Combination of X-ray diffraction (XRD) and scanning electron microscopy (SEM) was used for investigation of local composition gradients in the hard-phases of cermets. XRD revealed distribution of lattice parameters in hard-phase grains, from which the composition gradients in the hard-phases were estimated using an appropriate microstructure model. This microstructure model was build with the aid of SEM micrographs, which were taken with back-scattered electrons (BSE) and completed by the registration of the electron back-scatter diffraction (EBSD) patterns and characteristic X-ray spectra. SEM/BSE yielded the first information about the spatial distribution of elements in individual hard-phase grains, SEM/EBSD about the morphology, the size and the size distribution of these grains. The final interpretation of the distribution of lattice parameters, which was obtained from the X-ray line profile analysis, was done with the aid of the local elemental analysis that was performed using SEM with the energy dispersive analysis of the characteristic X-ray spectra (EDX) and the known dependence of the lattice parameters on concentration. 相似文献
188.
Kerstin Hannemann Volker Puchta Ernst Simon Herta Ziegler Gunter Ziegler Gerhard Spiteller 《Lipids》1989,24(4):296-298
The observation that F-acids (1) occur in rat chow initiated a search for F-acids in human diet. We observed that the amount
of F-acids with a pentyl side chain in α-position taken up with a one-day diet correlates well with the amount of excreted
degradation products, the pentyl urofuran acids (2), (3) and (4). Therefore it can be concluded that F-acids with a pentyl
side chain are not produced in the human body but are introduced through the diet. The origin of F-acids carrying an α-propyl
side chain is less clear. The amount of propyl-urofuran acids (2) and (3) excreted in urine was found in one case out of three
to be five times higher than the amount of F-acids carrying a propyl group in α-position taken up by the diet. Therefore,
it can presently not be excluded that a portion of the propyl F-acids is produced by the body.
F-acids found in human food are mainly introduced into the body by vegetables and fruits. F-acids were found also in birch
leaves in considerable amounts, as well as in grasses, dandelion and clover leaves. Thus, we can conclude that F-acids are
common constituents of plants. 相似文献
189.
Ralph Schöpke Roland Koch Sylke Mangold Volker Preuß Ralf Regel Angelika Striemann 《Grundwasser》2006,11(4):270-275
Sulfate-reducing processes were initiated in an aquifer with AMD-laden groundwater orthogonally to the located main groundwater flow direction. Groundwater was intermittently circulated between two wells. Substrate (methanol) and nutrients were added to this flow. After one year a sulphate-reducing reactor was formed in the aquifer, that precipitated FeS and decreased the acidity. These effects could still be observed one year after cessation of substrate amendment. 相似文献
190.