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排序方式: 共有305条查询结果,搜索用时 15 毫秒
111.
Hassan AA Akineden O Kress C Estuningsih S Schneider E Usleber E 《International journal of food microbiology》2007,116(2):214-220
The gene encoding the 16S rRNA of Enterobacter (E.) sakazakii (ATCC 29544, plus four strains isolated from powdered infant formula) was studied, and the sequence compared with those of other Enterobacteriaceae in aspects of genetic variability. Sequence differences between E. sakazakii and other Enterobacteriaceae within the hypervariable regions V1, V2, and V3, respectively, were used to develop two PCR methods for E. sakazakii. PCR1 employed a primer pair located in V1/V2, while PCR2 utilized a primer pair located in V1/V3, respectively. The two PCR methods were tested against a set of 57 E. sakazakii and 148 non-E. sakazakii isolates. PCR1 gave an amplicon with a size of 406 bp and resulted in 100% positive results for E. sakazakii, but also detected Citrobacter koseri/amalonaticus and all nine tested Salmonella enterica serovars. In contrast, PCR2 (amplicon size of 952 bp) gave positive results only for E. sakazakii, thus allowing specific identification of this species. 相似文献
112.
Trakic A Weber E Li BK Wang H Liu F Engstrom C Crozier S 《IEEE transactions on bio-medical engineering》2012,59(4):1068-1075
While recent studies have shown that rotating a single radio-frequency (RF) coil during the acquisition of magnetic resonance (MR) images provides a number of hardware advantages (i.e., requires only one RF channel, avoids coil-coil coupling and facilitates large-scale multinuclear imaging), they did not describe in detail how to build a rotating RF coil system. This paper presents detailed engineering information on the electromechanical design and construction of a MR-compatible RRFC system for human head imaging at 2 T. A custom-made (bladeless) pneumatic Tesla turbine was used to rotate the RF coil at a constant velocity, while an infrared optical encoder measured the selected frequency of rotation. Once the rotating structure was mechanically balanced and the compressed air supply suitably regulated, the maximum frequency of rotation measured ~14.5 Hz with a 2.4% frequency variation over time. MR images of a water phantom and human head were obtained using the rotating RF head coil system. 相似文献
113.
Melese Abdisa Yadata Carsten Werner Markos Tibbo Clemens B.A. Wollny Michael Wicke 《Meat science》2009
The objective of this work was to assess sensory quality and retail life of Horro beef muscles in Ethiopia. Six muscles: M. rhomboideus (RM), M. infraspinatus (IS), M. longissimus lumborum (LL), M. semimembranosus (SM), M. biceps femoris (BF) and M. rectus femoris (RF) were considered. Sensory quality of the muscles was rated by a 9-member trained panel for palatability, tenderness, juiciness, amount of connective tissue (ACT), lean color and surface discoloration and measured by Warner-Bratzler Shear Force (WBSF). Retail life of the six muscles were evaluated for CIE 1976 L∗a∗b∗ color values across 6 days. Significant differences (p < 0.05) between muscles for all sensory attributes and WBSF were found. Significant L∗a∗b∗ color values of muscles and USDA quality grades by retail life were found (p < 0.05). Significant correlations (p < 0.05 or p < 0.01) of key parameters were also identified. 相似文献
114.
Objectives To quantify the gain in time-series SNR that can be achieved in the amygdala by reducing EPI voxel size, and to assess the
extent to which this advantage is carried through to statistical significance in a group fMRI study, using a cognitive task
to trigger task-independent deactivation of anterior medial temporal structures.
Materials and methods Two groups of seven subjects were posed number-series tasks to induce deactivation of the Default Mode network. This is known
from PET work to include the amygdala, which lies in a region of high magnetic field gradient. In 3 T imaging, one group was
studied with high resolution EPI with 6 μl voxels, the other with lower resolution EPI with 17 μl voxels. Field maps were
acquired to allow field gradients in relevant ROIs to be assessed.
Results Time-series SNR was 45% higher in the amygdala in the high resolution EPI data than in the low resolution data. In activation
results, whilst there was good agreement between other areas, the involvement of the amygdala could only be demonstrated in
the high resolution data.
Conclusion We find that reduction in signal dephasing afforded by high resolution EPI is realized as a substantial increase in SNR and
BOLD sensitivity in group fMRI data. This has allowed the first demonstration of the involvement of the amygdala in the Default
Mode in fMRI. 相似文献
115.
Xiaomin Xu Dr. Hugo Brasselet Ewald P. J. Jongkind Prof. Dr. Miguel Alcalde Dr. Caroline E. Paul Prof. Dr. Frank Hollmann 《Chembiochem : a European journal of chemical biology》2022,23(6):e202200017
In this study, we developed a new bienzymatic reaction to produce enantioenriched phenylethanols. In a first step, the recombinant, unspecific peroxygenase from Agrocybe aegerita (rAaeUPO) was used to oxidise ethylbenzene and its derivatives to the corresponding ketones (prochiral intermediates) followed by enantioselective reduction into the desired (R)- or (S)-phenylethanols using the (R)-selective alcohol dehydrogenase (ADH) from Lactobacillus kefir (LkADH) or the (S)-selective ADH from Rhodococcus ruber (ADH-A). In a one-pot two-step cascade, 11 ethylbenzene derivatives were converted into the corresponding chiral alcohols at acceptable yields and often excellent enantioselectivity. 相似文献
116.
Robert Khnke Marcus Oliver Ahlers Moritz Alexander Birkelbach Florian Ewald Michael Krueger Imke Fiedler Bjrn Busse Max Heiland Tobias Vollkommer Martin Gosau Ralf Smeets Rico Rutkowski 《International journal of molecular sciences》2021,22(1)
Temporomandibular joint osteoarthritis (TMJ-OA) is a chronic degenerative disease that is often characterized by progressive impairment of the temporomandibular functional unit. The aim of this randomized controlled animal trial was a comparative analysis regarding the chondroregenerative potency of intra-articular stem/stromal cell therapy. Four weeks after combined mechanical and biochemical osteoarthritis induction in 28 rabbits, therapy was initiated by a single intra-articular injection, randomized into the following groups: Group 1: AB Serum (ABS); Group 2: Hyaluronic acid (HA); Group 3: Mesenchymal stromal cells (STx.); Group 4: Mesenchymal stromal cells in hyaluronic acid (HA + STx.). After another 4 weeks, the animals were euthanized, followed by histological examination of the removed joints. The histological analysis showed a significant increase in cartilage thickness in the stromal cell treated groups (HA + STx. vs. ABS, p = 0.028; HA + ST.x vs. HA, p = 0.042; STx. vs. ABS, p = 0.036). Scanning electron microscopy detected a similar heterogeneity of mineralization and tissue porosity in the subchondral zone in all groups. The single intra-articular injection of a stem cell containing, GMP-compliant advanced therapy medicinal product for the treatment of iatrogen induced osteoarthritis of the temporomandibular joint shows a chondroregenerative effect. 相似文献
117.
Wieser Ewald Seidl Markus Zeppelzauer Matthias 《Multimedia Tools and Applications》2017,76(6):8285-8303
Multimedia Tools and Applications - In this paper, we present a study on skeletonization of real-world shape data. The data stem from the cultural heritage domain and represent contact tracings of... 相似文献
118.
Some properties of ethylene-α-olefine-copolymers synthesized in the presence of Ziegler-catalysts were examined. It is shown that elongation and strength properties are not only dependent on molecular weight, molecular weight distribution and density but also on the length of the side chains. Copolymers with longer side chains show higher values of e.g. tensile impact strength than those with short side chains. 相似文献
119.
Andrea Carpinteri Aleksander Karolczuk Ewald Macha Sabrina Vantadori 《International Journal of Fracture》2002,115(1):87-99
The expected principal stress axes under multiaxial fatigue loading are determined by averaging the instantaneous Euler angles through suitable weight functions. Then, the fracture plane position is derived from such expected principal stress directions. Three weight functions based on stress parameters are discussed by comparing theoretical predictions with available test results related to six metallic materials under proportional and non-proportional loading. The fatigue fracture plane position under multiaxial loading may be established on the basis of the averaged direction of the maximum principal stress, with such a direction deduced by employing proper weight functions. 相似文献
120.
Schooler Carmi; Neumann Ewald; Caplan Leslie J.; Roberts Bruce R. 《Canadian Metallurgical Quarterly》1997,126(1):42
In this article, the authors respond to J. D. Cohen, K. O. Dunbar, D. M. Barch and T. S. Braver's (see record 1997-02838-005) comment on their target article (see record 1997-02838-004). The present article (a) takes issue with the characterization given by Cohen et al. of the authors' approach as a classical speed-of-processing account of Stroop effects, (b) discusses the value and relevance of other theoretical concepts, such as traditional accounts of working memory and parallel distributed processing (PDP) approaches to Stroop effects, (c) further examines the possibility that the differences the authors observed in Experiment 2 between normal participants' performance and that of participants with schizophrenia may have been due to distractor stimulus degradation, particularly for participants with schizophrenia, and (d) argues for the relevance of the prefrontal cortex, as well as other brain areas, in accounting for their results. The authors conclude with a final theoretical question. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献