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991.
Vidal Kallene Summer Aher Avinash J. Ventura Dora Fix Kremers Jan 《Documenta ophthalmologica. Advances in ophthalmology》2021,142(3):329-342
Documenta Ophthalmologica - To study the spatial retinal distribution of electroretinographic (ERG) responses that reflect signals in the L-/M-cone-opponent and luminance post-receptoral pathways.... 相似文献
992.
We propose a multicomponent fitting algorithm for multiecho T(2) data which allows for correction of T(2) distributions in the presence of stimulated echoes. Tracking the population of spins in many coherence pathways via the iterated method of the Extended Phase Graph algorithm allows for accurate quantification of echo magnitudes. The resulting decay curves allow for correction of errors due to nonideal refocusing pulses as a result of inhomogeneities in the B(1) transmit field. Non-Negative Least Squares fitting is used to quantify the magnitude of T(2) components at various T(2) values. This method, allowing calculation of the T(2) distribution with simultaneous extraction of the refocusing pulse flip angle, requires no change to image acquisition procedures and no extra data input. Validation by means of both simulations and in vivo data shows excellent interscan reproducibility while vastly improving the accuracy of extracted T(2) parameters in voxels where poor B(1) homogeneity leads to refocusing pulse flip angles significantly less than 180°. Most notably, myelin water fraction values in these regions are found to have increased consistency and accuracy. 相似文献
993.
Albermann ME Musshoff F Doberentz E Heese P Banger M Madea B 《International journal of legal medicine》2012,126(5):757-764
Ethyl glucuronide (EtG) and ethyl sulfate (EtS) are commonly used alcohol markers for previous alcohol consumption. Nevertheless, the optimum EtG cutoff for urinary abstinence tests is still being discussed, and no cutoff has been recommended for EtS yet. The aim of this study was to verify cutoffs by investigating EtG and EtS concentrations (c(EtG) and c(EtS)) in the urine of healthy persons after drinking small, but realistic amounts of alcohol (one or two glasses of beer or white wine), and to look for the window of detection in strongly alcohol-intoxicated patients who were beginning withdrawal treatment. Very high EtG and EtS concentrations were measured in the first urine samples of patients under withdrawal treatment. However, 24?h later, concentrations decreased considerably, and c (EtG)?0.5?mg/l and c (EtS)?0.1?mg/l were determined in 26.7?% (4/13) and 13.3?% (2/13) of the samples, respectively. Concentrations above 0.1?mg/l (EtG) and 0.05?mg/l (EtS) were measured for 23.5 and 20.5?h after consuming 0.1?l of white wine or 0.33?l of beer, and 24?h after the experiment, 75?% (9/12) of the urine samples were tested negative for EtG and EtS using the following cutoffs: EtG 0.5?mg/l and EtS 0.1?mg/l. In half of the samples, concentrations below 0.1?mg/l (EtG) and 0.05?mg/l (EtS) were detected. Urinary cutoffs for EtG of 0.5?mg/l or higher are not suitable for testing abstinence. Even 0.1?mg/l is not effective to detect the intake of small amounts of alcohol in the context of abstinence tests. For EtS, 0.05?mg/l were found to be a potential cutoff to exclude the repeated intake of alcohol. Yet, further research is required to verify this cutoff. For a limited time period, EtG and EtS concentrations within the range of these cutoffs are also detectable after unintentional consumption of alcohol. Participants of abstinence programs have to be informed about the alcohol content of certain foods and beverages whose consumption is in conflict with strict abstinence. 相似文献
994.
Fritz Juliusberg Walther Pick V. Lion Max Joseph Max Leibkind Alfred Kraus Harald Boas F. Münchheimer Silberstein Wilhelm Balban F. Lewandowsky Max Winkler Theodor Baer Viktor Bandler H. Hecht Marg Stern Hans Burkhard 《Archives of dermatological research》1917,122(11):987-1035
Ohne Zusammenfassung 相似文献
995.
996.
Vera Mahler Alexander Nast Andrea Bauer Detlef Becker Jochen Brasch Kristine Breuer Heinrich Dickel Hans Drexler Peter Elsner Johannes Geier Swen Malte John Burkhard Kreft Arno Kllner Hans Merk Hagen Ott Silvia Pleschka Maria Portisch Petra Spornraft‐Ragaller Elke Weisshaar Thomas Werfel Margitta Worm Axel Schnuch Wolfgang Uter 《Journal der Deutschen Dermatologischen Gesellschaft》2019,17(10):1075-1093
997.
Robert Krikorian Matthew R. Skelton Suzanne S. Summer Marcelle D. Shidler Patrick G. Sullivan 《Nutrients》2022,14(8)
Late-life dementia typically develops over a period of many years beginning in midlife. Prevalence of metabolic disturbance also accelerates in middle age and is a prominent risk factor for dementia. Preliminary studies indicate that blueberry supplementation can improve cognitive performance and influence metabolism and brain function and therefore may have a role in early intervention to prevent neurodegeneration. In a randomized controlled trial, we investigated the effects of daily blueberry supplementation in a middle-aged sample of insulin-resistant participants with elevated risk for future dementia. We enrolled overweight men and women, aged 50 to 65 years, with subjective cognitive decline (SCD) and performed pre- and post-intervention assessments of cognition and metabolism and exploratory measures of peripheral mitochondrial function. We observed improved performances for the blueberry group on measures of lexical access, p = 0.003, and memory interference, p = 0.04, and blueberry-treated participants reported reduced memory encoding difficulty in daily life activities, p = 0.03. The blueberry-treated group also exhibited correction of peripheral hyperinsulinemia, p = 0.04, and a modest trend for increased mitochondrial uncoupling, p = 0.11. The cognitive findings indicated improved executive ability in this middle-aged sample. In addition, the changes in metabolic and bioenergetic measures imply potential mechanistic factors associated with anthocyanin and proanthocyanidin actions. The demonstration of these benefits in middle-aged individuals with insulin resistance and SCD suggests that ongoing blueberry supplementation may contribute to protection against cognitive decline when implemented early in at-risk individuals. 相似文献
998.
It is known that sound pressure, measured in couplers via a probe-tube microphone, often shows a pressure vs frequency response that drops sharply at a single frequency. In this study sound pressure was theoretically determined at various locations within a hard-walled cylindrical cavity, driven by a constant-volume velocity source with circular symmetry. At each location in the volume, a transfer impedance was defined as the ratio of pressure to inlet-volume velocity. In the region around the inlet, the transfer impedance passes through zero as it changes from negative to positive reactance with increasing frequency. Two hard-walled cavity examples were examined in detail (1) the main cavity of a 2-cm3 HA-2 coupler, and (2) a cavity having dimensions approximately equal to the occluded ear canal between an ear-mold tip and the eardrum. Contours of constant minimum sound pressure vs frequency are given for these two cylindrical volumes with experimental verification. Implications for probe microphone calibration and measurement of sound pressure in ears are discussed. 相似文献
999.
1000.