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101.
Loretta Chiuh-Yeou Cheong Erwin Chargaff 《Proceedings of the National Academy of Sciences of the United States of America》1969,64(1):241-246
This paper discusses the evidence that two fractions obtained by the chromatography of denatured DNA of phage T3 on columns of methylated albumin-kieselguhr represent the complementary strands. This evidence derives from a variety of temperature-absorbance measurements and from the base composition of the RNA products synthesized by RNA polymerase under the direction of the two single-stranded DNA templates. 相似文献
102.
Confirmation of Correlations and Common Quantitative Trait Loci Between Neurotensin Receptor Density and Hypnotic Sensitivity to Ethanol 总被引:3,自引:0,他引:3
V. Gene Erwin Vaughn M. Gehle Kirsten Davidson Richard A. Radcliffe 《Alcoholism, clinical and experimental research》2001,25(12):1699-1707
BACKGROUND: In previous studies, genetic correlations were observed between hypnotic sensitivity to ethanol and high-affinity neurotensin receptor (NTS1) binding. Provisional quantitative trait loci (QTLs) were identified for these traits, and some of these QTLs were found on common chromosomal regions. In continued efforts to examine the relationship between NTS1 binding capacity and hypnotic sensitivity to ethanol, studies were designed to confirm correlations between NTS1 densities in the brain, duration of ethanol-induced loss of righting reflex (LORR), and blood ethanol concentrations at regain of righting reflex (BECRR). Another purpose of the study was to confirm QTLs for these traits. METHODS: ILS X ISS F2 mice and HAS X LAS F2 rats as well as the progenitors were tested for LORR, BECRR, and NTS1 densities. Phenotypic correlations were calculated between LORR and BECRR and between these measures and NTS1 densities in striatum from both mice and rats. The F2 mice were genotyped by using polymorphic markers for five previously reported QTLs for LORR to confirm QTLs for BECRR and NTS1 densities in striatum, ventral midbrain, and frontal cortex. RESULTS: Phenotypic correlations were found between LORR and BECRR (r = -0.66 to -0.74, p < 10(-9)) and between these measures and NTS1 densities in striatum (r = 0.28-0.38, p < 10(-2)) from both mice and rats. QTLs for LORR and BECRR (lod score = 2-6) were found in common regions of chromosomes 1, 2, and 15. By using the combined results from a previous LSXSS RI study and the current results, a suggestive QTL (lod score = 3.1) for striatal NTS1 receptor densities was found on chromosome 15 at approximately 60 cM, in the same region as the chromosome 15 LORR/BECRR QTL. CONCLUSIONS: The results are in agreement with previously reported correlations and QTLs for NTS1 receptor densities and measures of hypnotic sensitivity to ethanol in mice and extend those correlations to another species, the rat. These findings support a role for NTS1 in genetically mediated differences in hypnotic sensitivity to ethanol. 相似文献
103.
Survey of DNA Polymerase Activity During the Early Development of Drosophila melanogaster 总被引:1,自引:0,他引:1
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Lola Margulies Erwin Chargaff 《Proceedings of the National Academy of Sciences of the United States of America》1973,70(10):2946-2950
The pattern of DNA polymerase activity in developing Drosophila melanogaster has been studied in seven stages of embryonic development as well as in unfertilized eggs. The crude polymerase-containing extracts, most likely of cytoplasmic origin, utilize, in the following order of decreasing template efficiency, "activated" calfthymus DNA, poly(A).oligo(dT), and poly(A).oligo(U). The highest enzymes levels occur in unfertilized eggs; the activity remains high during the first 9 hr of embryogenesis, but shows a progressive decline in the later stages. Deoxyribonuclease exhibits a similar trend. The unfertilized eggs of two genotypically different females had nearly identical levels of DNA polymerase. 相似文献
104.
Erwin?Stolz Franziska?Gro?sch?dl Hannes?Mayerl éva?Rásky Wolfgang?FreidlEmail author 《BMC medical ethics》2015,16(1):81
Background
End-of-life decisions remain a hotly debated issue in many European countries and the acceptance in the general population can act as an important anchor point in these discussions. Previous studies on determinants of the acceptance of end-of-life interventions in the general population have not systematically assessed whether determinants differ between withdrawal of life-prolonging treatment (WLPT) and euthanasia (EUT).Methods
A large, representative survey of the Austrian adult population conducted in 2014 (n?=?1,971) included items on WLPT and EUT. We constructed the following categorical outcome: (1) rejection of both WLPT and EUT, (2) approval of WLPT but rejection of EUT, and (3) approval of both WLPT and EUT. The influence of socio-demographics, personal experiences, and religious and socio-cultural orientations on the three levels of approval were assessed via multinomial logistic regression analysis.Results
Higher education and stronger socio-cultural liberal orientations increased the likelihood of approving both WLPT and EUT; personal experience with end-of-life care increased only the likelihood of approval of WLPT; and religiosity decreased approval of EUT only.Conclusion
This study found evidence for both shared (education, liberalism) and different (religiosity, care experiences) determinants for the acceptance of WLPT and EUT.105.
Margo M.C. van Mol Esther C. Bakker Marjan D. Nijkamp Erwin J.O. Kompanje Jan Bakker Lisbeth Verharen 《Patient education and counseling》2014
Objective
To examine the potential of a questionnaire (CQI ‘R-ICU’) to measure the quality of care from the perspective of relatives in the Intensive Care Unit (ICU).Methods
A quantitative survey study has been undertaken to explore the psychometric properties of the instrument, which was sent to 282 relatives of ICU patients from the Erasmus MC, an academic hospital in Rotterdam, the Netherlands. Factor-analyses were performed to explore the underlying theoretical structure.Results
Survey data from 211 relatives (response rate 78%) were used for the analysis. The overall reliability of the questionnaire was sufficiently high; two of the four underlying factors, namely ‘Communication’ and ‘Involvement’, were significant predictors. Two specific aspects of care that needed the most improvement were missing information about meals and offering an ICU diary. There is a significant difference in mean communication with nurses among the four wards in Erasmus MC.Conclusions
The CQI ‘R-ICU’ seems to be a valid, reliable and usable instrument. The theoretical fundament appears to be related to communication.Practice implications
The newly developed instrument can be used to provide feedback to health care professionals and policy makers in order to evaluate quality improvement projects with regard to relatives in the ICU. 相似文献106.
Variable temporoinsular cortex neuroanatomy in primates suggests a bottleneck effect in eastern gorillas
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Sarah K. Barks Amy L. Bauernfeind Christopher J. Bonar Michael R. Cranfield Alexandra A. de Sousa Joseph M. Erwin William D. Hopkins Albert H. Lewandowski Antoine Mudakikwa Kimberley A. Phillips Mary Ann Raghanti Cheryl D. Stimpson Patrick R. Hof Karl Zilles Chet C. Sherwood 《The Journal of comparative neurology》2014,522(4):844-860
We describe an atypical neuroanatomical feature present in several primate species that involves a fusion between the temporal lobe (often including Heschl's gyrus in great apes) and the posterior dorsal insula, such that a portion of insular cortex forms an isolated pocket medial to the Sylvian fissure. We assessed the frequency of this fusion in 56 primate species (including apes, Old World monkeys, New World monkeys, and strepsirrhines) by using either magnetic resonance images or histological sections. A fusion between temporal cortex and posterior insula was present in 22 species (seven apes, two Old World monkeys, four New World monkeys, and nine strepsirrhines). The temporoinsular fusion was observed in most eastern gorilla (Gorilla beringei beringei and G. b. graueri) specimens (62% and 100% of cases, respectively) but was seen less frequently in other great apes and was never found in humans. We further explored the histology of this fusion in eastern gorillas by examining the cyto‐ and myeloarchitecture within this region and observed that the degree to which deep cortical layers and white matter are incorporated into the fusion varies among individuals within a species. We suggest that fusion between temporal and insular cortex is an example of a relatively rare neuroanatomical feature that has become more common in eastern gorillas, possibly as the result of a population bottleneck effect. Characterizing the phylogenetic distribution of this morphology highlights a derived feature of these great apes. J. Comp. Neurol. 522:844–860, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
107.
Vrieze A Van Nood E Holleman F Salojärvi J Kootte RS Bartelsman JF Dallinga-Thie GM Ackermans MT Serlie MJ Oozeer R Derrien M Druesne A Van Hylckama Vlieg JE Bloks VW Groen AK Heilig HG Zoetendal EG Stroes ES de Vos WM Hoekstra JB Nieuwdorp M 《Gastroenterology》2012,143(4):913-916.e7
Alterations in intestinal microbiota are associated with obesity and insulin resistance. We studied the effects of infusing intestinal microbiota from lean donors to male recipients with metabolic syndrome on the recipients' microbiota composition and glucose metabolism. Subjects were assigned randomly to groups that were given small intestinal infusions of allogenic or autologous microbiota. Six weeks after infusion of microbiota from lean donors, insulin sensitivity of recipients increased (median rate of glucose disappearance changed from 26.2 to 45.3 μmol/kg/min; P < .05) along with levels of butyrate-producing intestinal microbiota. Intestinal microbiota might be developed as therapeutic agents to increase insulin sensitivity in humans; www.trialregister.nl; registered at the Dutch Trial Register (NTR1776). 相似文献
108.
109.
NB Eloy N Gonzalez J Van Leene K Maleux H Vanhaeren L De Milde S Dhondt L Vercruysse E Witters R Mercier L Cromer GT Beemster H Remaut MC Van Montagu G De Jaeger PC Ferreira D Inzé 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(34):13853-13858
The anaphase-promoting complex/cyclosome (APC/C) is a large multiprotein E3 ubiquitin ligase involved in ubiquitin-dependent proteolysis of key cell cycle regulatory proteins, including the destruction of mitotic cyclins at the metaphase-to-anaphase transition. Despite its importance, the role of the APC/C in plant cells and the regulation of its activity during cell division remain poorly understood. Here, we describe the identification of a plant-specific negative regulator of the APC/C complex, designated SAMBA. In Arabidopsis thaliana, SAMBA is expressed during embryogenesis and early plant development and plays a key role in organ size control. Samba mutants produced larger seeds, leaves, and roots, which resulted from enlarged root and shoot apical meristems, and, additionally, they had a reduced fertility attributable to a hampered male gametogenesis. Inactivation of SAMBA stabilized A2-type cyclins during early development. Our data suggest that SAMBA regulates cell proliferation during early development by targeting CYCLIN A2 for APC/C-mediated proteolysis. 相似文献