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971.
Erika Post 《Planta》1938,28(4):743-744
Ohne Zusammenfassung  相似文献   
972.
Background. Cardiac magnetic resonance (CMR) imaging has evolved over the last decade into an indispensable diagnostic instrument. CMR imaging noninvasively provides structural, functional and morphological information with high spatial resolution and an unlimited field of view. Since October 2006 the VieCuri Medical Centre in Venlo has a CMR scanner at its disposal.Objectives. The goal of this study was to analyse the impact of CMR imaging on diagnosis and treatment in daily practice in the setting of a medium-volume peripheral hospital.Methods. All patients who underwent CMR imaging between October 2006 and November 2008 were included in this analysis. The medical history before and after the CMR scan, the application form for CMR imaging and the outcome of the scans were reviewed. CMR images, obtained using a 1.5-T magnetic resonance imaging system, were reviewed by a multidisciplinary team.Results. In 235 patients CMR imaging demonstrated one or more abnormalities, whereas CMR imaging did not identify any abnormalities in 148 patients. CMR imaging confirmed an expected finding in 166 cases, identified an unexpected condition in 69 cases, ruled out an expected finding in 59 cases and ruled out a suspected condition in 89 cases. Due to better insight into diagnosis, CMR imaging resulted in a change of treatment in 166 of the total of 383 CMR scans (43%).Conclusion. In a relevant number of cases CMR imaging leads to a change in the treatment of a patient, proving the value of CMR imaging as a diagnostic modality. Therefore, CMR imaging is an excellent opportunity for peripheral medical centres to improve efficiency and the standard of patient care. (Neth Heart J 2010;18:524–30.)  相似文献   
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977.
C B Post 《Biopolymers》1984,23(3):601-605
The ends of rather short double-helical DNA segments (approximately two persistence lengths) can be enzymatically joined to form closed circles. Such covalent closure into circles is a measure of the likelihood of the two ends of the DNA coming into close contact. There is a length of DNA for which loop formation is most likely to occur. We have determined the chain-length dependence of loop formation for stiff chains using computer-generated chains of cylinders. The distribution from which the values for the angles between cylinders were chosen relates the chain parameters to a given chain persistence. Our results are compared with those of other theories, including a statistical wormlike chain model, and with the experimental measurements for ring closure of DNA restriction fragments.  相似文献   
978.
Testicular examination of male Onchocerca dukei and German O. tarsicola revealed five pairs of chromosomes, which is typical of most filariae. In contrast to German O. tarsicola, specimens from Sweden had only three pairs of chromosomes.  相似文献   
979.
Erika Post 《Hydrobiologia》1957,9(2-3):105-105
Ohne Zusammenfassung  相似文献   
980.
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