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991.
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Melanie Ott Miriam Huls Michael G. Cornelius Gert Fricker 《Pharmaceutical research》2010,27(5):811-822
Purpose
The purpose of this study was to investigate the short-term signaling effects of St. John’s Wort (SJW) extract and selected SJW constituents on the blood-brain barrier transporter P-glycoprotein and to describe the role of PKC in the signaling. 相似文献993.
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Norbert Krämer Christian Reinelt Gert Richter Anselm Petschelt Roland Frankenberger 《Dental materials》2009,25(6):750-759
ObjectivesThis controlled prospective split-mouth study evaluated the clinical behavior of two different resin composites in extended Class II cavities over a period of four years.MethodsThirty patients received 68 direct resin composite restorations (Grandio bonded with Solobond M: n = 36, Tetric Ceram bonded with Syntac: n = 32) by one dentist in a private practice. All restorations were replacement fillings, 24 cavities (35%) revealed no enamel at the bottom of the proximal box, in 33 cavities (48%) the proximal enamel width was less than 0.5 mm. The restorations were examined according to modified USPHS criteria at baseline, and after six months, one, two, and four years. At each recall, impressions were taken for replica preparation. Replicas of 44 select subjects were assessed for marginal quality under a stereo light microscope (SLM) at 130× and 22 replicas were assessed under a scanning electron microscope (SEM) at 200×.ResultsBoth recall rate and survival rate were 100% after four years of clinical service. No significant difference was found between the restorative materials (p > 0.05; Mann–Whitney U-test). Hypersensitivities were significantly reduced over time (p < 0.05; Friedman test). A significant deterioration over time was found for the criteria marginal integrity (66% bravo after four years), tooth integrity (15% bravo), filling integrity (73% bravo) and proximal contact (p < 0.05; Friedman test). SLM and SEM analysis of restoration margins revealed differences in the amount of perfect margins, in favor of Tetric Ceram (p < 0.05).SignificancesBoth materials performed satisfactorily over the four-year observation period. Due to the extension of the restorations, wear was clearly visible after four years of clinical service with 50% bravo ratings. 相似文献
996.
Renate Zeevaert Franois Foulquier David Cheillan Isabelle Cloix Nathalie Guffon Luisella Sturiale Domenico Garozzo Gert Matthijs Jaak Jaeken 《European journal of medical genetics》2009,52(5):303-305
We describe a patient homozygous for a novel mutation in COG7, coding for one of the subunits of the Conserved Oligomeric Golgi complex, involved in retrograde vesicular trafficking. His brother showed a similar clinical syndrome and glycosylation defect but no DNA could be obtained from this patient. This mutation, c.170-7A > G, activates a cryptic splice acceptor and leads to the insertion of 2 amino acids at protein level (p.56–57insAT). The insertion disturbs the structure and function of the Conserved Oligomeric Golgi complex. In comparison to the previously described patients with a different COG7 mutation, intrauterine growth retardation and dysmorphic features were absent and there was a longer survival. 相似文献
997.
Performance groups in adult cochlear implant users: speech perception results from 1984 until today.
Beate Krueger Gert Joseph Urte Rost Angelika Strauss-Schier Thomas Lenarz Andreas Buechner 《Otology & neurotology》2008,29(4):509-512
INTRODUCTION: More than 3,000 patients have received a cochlear implant in Hannover. METHODS: A group of 864 patients was selected from the main group for the analysis of speech perception development. Depending on the term of introduction of new implant technology, the viewed group was divided into 5 subgroups. RESULTS: The test battery during regular clinical checkups included speech perception tests. Those tests changed during 20 years; only speech tracking and monosyllable word test remained and were the bases for forming performance classes shown in this study. Three performance classes can be specified for all 5 subgroups by mean values and standard deviations. CONCLUSION: In all subgroups, an improvement of speech perception can be observed over time. The current patient group showed significant better performing results than those of the first group. 相似文献
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This paper describes and discusses the phenomenon ‘predatory publishing’, in relation to both academic journals and books, and suggests a list of characteristics by which to identify predatory journals. It also raises the question whether traditional publishing houses have accompanied rogue publishers upon this path. It is noted that bioethics as a discipline does not stand unaffected by this trend. Towards the end of the paper it is discussed what can and should be done to eliminate or reduce the effects of this development. The paper concludes that predatory publishing is a growing phenomenon that has the potential to greatly affect both bioethics and science at large. Publishing papers and books for profit, without any genuine concern for content, but with the pretence of applying authentic academic procedures of critical scrutiny, brings about a worrying erosion of trust in scientific publishing. 相似文献
1000.
Zhila Taherzadeh PharmD Lizzy M. Brewster MD PhD Gert A. Van Montfrans MD PhD Ed VanBavel PhD 《Journal of clinical hypertension (Greenwich, Conn.)》2010,12(6):431-438
J Clin Hypertens (Greenwich). 2010;12:431–438. ©2010 Wiley Periodicals, Inc. The risk of development of hypertension is greater in black people compared to white people through mechanisms that are poorly understood. Several biological and environmental factors have been proposed. Based on the role of an increased peripheral resistance in the pathogenesis of hypertension, the authors focus in this systematic review on ethnic differences in function and mechanical properties of resistance arteries in normotensive participants. PubMed was systematically searched for papers on ethnic differences in vascular function and structure. A total of 620 papers were retrieved, of which 31 papers were included in the analysis. The available data indicate that compared to normotensive whites, normotensive black people have enhanced vascular reactivity to sympathetic stimulation, attenuated responses to vasodilators, and a relatively narrow vascular lumen diameter. Of these mechanisms, the reduced vasodilation and reduced nitric oxide bioavailability in the vascular wall seem to form the most important distinction between resistance vessel properties of black and white participants. 相似文献