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排序方式: 共有1461条查询结果,搜索用时 15 毫秒
1.
Ivania Pereira Stephanie Weber Stephan Holzer Georg Fischer Clemens Vass Hemma Resch 《PloS one》2015,10(3)
This work intends to assess circumpapillary retinal vessel density (RVD) at a 3.46 mm diameter circle and correlate it with circumpapillary retinal nerve fiber layer (RNFL) thickness measured with Fourier-Domain Optical Coherence Tomography. Furthermore, it aims to evaluate the reduction of intersubject variability of RNFL when considering RVD as a source of information for RNFL distribution. For that, 106 healthy subjects underwent circumpapillary RNFL measurement. Using the scanning laser ophthalmoscope fundus image, thickness and position of retinal vessels were assessed and integrated in a 256-sector RVD profile. The relationship between local RVD value and local RNFL thickness was modeled by linear regression. RNFL was then compensated for RVD variation by regression formulas. A strong statistically significant intrasubject correlation was found for all subjects between RVD and RNFL profiles (mean R = 0.769). In the intersubject regression analysis, 247 of 256 RNFL sectors showed a statistically significant positive correlation with RVD (mean R = 0.423). RVD compensation of RNFL resulted in a relative reduction of up to 20% of the intersubject variance. In conclusion, RVD in a 3.46mm circle has a clinically relevant influence on the RNFL distribution. RVD may be used to develop more individualized normative values for RNFL measurement, which might improve early diagnosis of glaucoma. 相似文献
2.
Katrin Kausch Clemens R. Müller Tiemo Grimm Kenneth Ricker Marcella Rietschel Sabine Rudnik-Schöneborn Klaus Zerres 《Human genetics》1991,86(3):317-318
Summary Two recent articles have reported the linkage of a gene for recessive spinal muscular atrophy (SMA) on the chromosome region 5q11.2–13.3. Our data show no linkage of the dominantly inherited forms of SMA to this chromosome region. 相似文献
3.
Clemens Benjamin J. Weitkamp Laurie Siwicke Kevin Wade Joy Harris Julianne Hess Jon Porter Laurie Parker Keith Sutton Trent Orlov Alexei M. 《Reviews in Fish Biology and Fisheries》2019,29(4):767-788
Reviews in Fish Biology and Fisheries - Pacific lamprey Entosphenus tridentatus has an anadromous life cycle that begins with larvae that filter-feed in freshwater, followed by transformation into... 相似文献
4.
Reay DP Niizawa GA Watchko JF Daood M Reay JC Raggi E Clemens PR 《Molecular medicine (Cambridge, Mass.)》2012,18(1):466-476
Gene therapy studies for Duchenne muscular dystrophy (DMD) have focused on viral vector-mediated gene transfer to provide therapeutic protein expression or treatment with drugs to limit dystrophic changes in muscle. The pathological activation of the nuclear factor (NF)-κB signaling pathway has emerged as an important cause of dystrophic muscle changes in muscular dystrophy. Furthermore, activation of NF-κB may inhibit gene transfer by promoting inflammation in response to the transgene or vector. Therefore, we hypothesized that inhibition of pathological NF-κB activation in muscle would complement the therapeutic benefits of dystrophin gene transfer in the mdx mouse model of DMD. Systemic gene transfer using serotype 9 adeno-associated viral (AAV9) vectors is promising for treatment of preclinical models of DMD because of vector tropism to cardiac and skeletal muscle. In quadriceps of C57BL/10ScSn-Dmd(mdx)/J (mdx) mice, the addition of octalysine (8K)-NF-κB essential modulator (NEMO)-binding domain (8K-NBD) peptide treatment to AAV9 minidystrophin gene delivery resulted in increased levels of recombinant dystrophin expression suggesting that 8K-NBD treatment promoted an environment in muscle tissue conducive to higher levels of expression. Indices of necrosis and regeneration were diminished with AAV9 gene delivery alone and to a greater degree with the addition of 8K-NBD treatment. In diaphragm muscle, high-level transgene expression was achieved with AAV9 minidystoophin gene delivery alone; therefore, improvements in histological and physiological indices were comparable in the two treatment groups. The data support benefit from 8K-NBD treatment to complement gene transfer therapy for DMD in muscle tissue that receives incomplete levels of transduction by gene transfer, which may be highly significant for clinical applications of muscle gene delivery. 相似文献
5.
Ralf S. Eschbach Wolfgang P. Fendler Philipp M. Kazmierczak Marcus Hacker Axel Rominger Janette Carlsen Heidrun Hirner-Eppeneder Jessica Schuster Matthias Moser Lukas Havla Moritz J. Schneider Michael Ingrisch Lukas Spaeth Maximilian F. Reiser Konstantin Nikolaou Clemens C. Cyran 《PloS one》2015,10(2)
ObjectivesTo investigate a multimodal, multiparametric perfusion MRI / 18F-fluoro-deoxyglucose-(18F-FDG)-PET imaging protocol for monitoring regorafenib therapy effects on experimental colorectal adenocarcinomas in rats with immunohistochemical validation.ResultsRegorafenib significantly (p<0.01) suppressed PF (81.1±7.5 to 50.6±16.0 mL/100mL/min), PV (12.1±3.6 to 7.5±1.6%) and PS (13.6±3.2 to 7.9±2.3 mL/100mL/min) as well as TTB (3.4±0.6 to 1.9±1.1) between baseline and day 7. Immunohistochemistry revealed significantly (p<0.03) lower tumor microvascular density (CD-31, 7.0±2.4 vs. 16.1±5.9) and tumor cell proliferation (Ki-67, 434.0 ± 62.9 vs. 663.0 ± 98.3) in the therapy group. Perfusion MRI parameters ΔPF, ΔPV and ΔPS showed strong and significant (r = 0.67-0.78; p<0.01) correlations to the PET parameter ΔTTB and significant correlations (r = 0.57-0.67; p<0.03) to immunohistochemical Ki-67 as well as to CD-31-stainings (r = 0.49-0.55; p<0.05).ConclusionsA multimodal, multiparametric perfusion MRI/PET imaging protocol allowed for non-invasive monitoring of regorafenib therapy effects on experimental colorectal adenocarcinomas in vivo with significant correlations between perfusion MRI parameters and 18F-FDG-PET validated by immunohistochemistry. 相似文献
6.
Christine Wittmann Markus Reischl Asmi H. Shah Eva Kronfuss Ralf Mikut Urban Liebel Clemens Grabher 《PloS one》2015,10(10)
Tissue injury and infection trigger innate immune responses. However, dysregulation may result in chronic inflammation and is commonly treated with corticosteroids and non-steroidal anti-inflammatory drugs. Unfortunately, long-term administration of both therapeutic classes can cause unwanted side effects. To identify alternative immune-modulatory compounds we have previously established a novel screening method using zebrafish larvae. Using this method we here present results of an in vivo high-content drug-repurposing screen, identifying 63 potent anti-inflammatory drugs that are in clinical use for other indications. Our approach reveals a novel pro-inflammatory role of nitric oxide. Nitric oxide affects leukocyte recruitment upon peripheral sensory nervous system or epithelial injury in zebrafish larvae both via soluble guanylate cyclase and in a soluble guanylate cyclase -independent manner through protein S-nitrosylation. Together, we show that our screening method can help to identify novel immune-modulatory activities and provide new mechanistic insights into the regulation of inflammatory processes. 相似文献
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8.
Gerhard Bringmann Klaus-Peter Gulden Daniel Vitt Klaus Birken Clemens Helf 《Journal of molecular modeling》1995,1(3):161-175
AdaptivSearch is the first adaptive strategy based algorithm for the rational and economical construction of n-dimensional hypersurfaces. AdaptivSearch works iteratively: At each step it parcels out the definition range into several triangles, evaluates the worst according to a built-in error criterion, and refines the approximation to the unknown function by choosing the barycenter of this partial area as the node to be calculated next. Based upon the error criterion, AdaptivSearch selectively approaches those parts of the hypersurface in which the curvature exhibits the strongest changes. Some examples of AdaptivSearch applications for both analytical functions and chemical model surfaces are given in order to demonstrate the behavior of the algorithm. These show its broad applicability and the usefulness, especially for chemical problems. 相似文献
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10.
Since the nineteenth century, bone beds in the Rhaetic Sandstone (Rhätsandstein) exposed around Bebenhausen near Tübingen, Baden-Württemberg, have been a source of small vertebrate fossils. These bone beds were part of deltas formed during a stillstand in a marine transgression from the western and northern parts of the Germanic Basin. The fossils in these bone beds appear to be time-averaged assemblages of Rhaeto-Liassic or older age. A collection of fossils from excavations at Olgahain made in 1948 augmented those reported by E. von Huene (Jahreshefte des Vereins vaterländische Naturkunde in Württemberg 84:65–128, 1933). The synapsids, other than tritylodonts, represented by fossils from the Olgahain locality include Tricuspes, a non-mammaliaform eucynodont; the haramiyid Thomasia antiqua is the most abundantly represented mammaliaform, and a morganucodontid. Tricuspes tuebingensis was based on a tooth found at the nearby Gaisbrunnen locality. Tricuspes tuebingensis, Thomasia antiqua, and a probably different morganucodontid are known from the Hallau bone bed (Switzerland), which apparently is older than the Olgahain bone bed in Baden-Württemberg. 相似文献