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991.
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MYPM Yusof MM Dasor F Ariffin NH Reduwan WNWA Kamil MC Mah 《Australian dental journal》2020,65(4):308-312
This report presents two cases of idiopathic osteosclerosis involving the maxilla and mandible which were identified as a buccally impacted canine and a retained root, respectively, on clinical and plain radiographical examinations. Both patients were females who presented with hypodontia. Radiographic evaluation revealed solitary well-defined radiopaque masses with thickened cortical border. Both patients were undergoing orthodontic treatment and one was planned for a surgical traction of unerupted tooth prior to cone-beam CT assessment. In this report, we reviewed the clinical findings and explained the radiographic appearance of idiopathic osteosclerosis through plain radiographs and cone-beam CT to facilitate its identification among general dentists and oral and maxillofacial radiologists. 相似文献
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Regional neurochemical profiles in the human brain measured by 1H MRS at 7 T using local B1 shimming
Uzay E. Emir Edward J. Auerbach Pierre‐Francois Van De Moortele Małgorzata Marjańska Kamil Uğurbil Melissa Terpstra Ivan Tkáč Gülin Öz 《NMR in biomedicine》2012,25(1):152-160
Increased sensitivity and chemical shift dispersion at ultra‐high magnetic fields enable the precise quantification of an extended range of brain metabolites from 1H MRS. However, all previous neurochemical profiling studies using single‐voxel MRS at 7 T have been limited to data acquired from the occipital lobe with half‐volume coils. The challenges of 1H MRS of the human brain at 7 T include short T2 and complex B1 distribution that imposes limitations on the maximum achievable B1 strength. In this study, the feasibility of acquiring and quantifying short‐echo (TE = 8 ms), single‐voxel 1H MR spectra from multiple brain regions was demonstrated by utilizing a 16‐channel transceiver array coil with 16 independent transmit channels, allowing local transmit B1 (B1+) shimming. Spectra were acquired from volumes of interest of 1–8 mL in brain regions that are of interest for various neurological disorders: frontal white matter, posterior cingulate, putamen, substantia nigra, pons and cerebellar vermis. Local B1+ shimming substantially increased the transmit efficiency, especially in the peripheral and ventral brain regions. By optimizing a STEAM sequence for utilization with a 16‐channel coil, artifact‐free spectra were acquired with a small chemical shift displacement error (<5% /ppm/direction) from all regions. The high signal‐to‐noise ratio enabled the quantification of neurochemical profiles consisting of at least nine metabolites, including γ‐aminobutyric acid, glutamate and glutathione, in all brain regions. Significant differences in neurochemical profiles were observed between brain regions. For example, γ‐aminobutyric acid levels were highest in the substantia nigra, total creatine was highest in the cerebellar vermis and total choline was highest in the pons, consistent with the known biochemistry of these regions. These findings demonstrate that single‐voxel 1H MRS at ultra‐high field can reliably detect region‐specific neurochemical patterns in the human brain, and has the potential to objectively detect alterations in neurochemical profiles associated with neurological diseases. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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The concept of paleolithic diet is based on an assumption that modern human is not evolutionarily adapted to contemporary nutrition, which may result in high frequency of diseases considered as civilization-related such as ischemic heart disease, arterial hypertension, obesity, diabetes, cancer and other. In the article, reconstruction of the diet is presented and it is compared to modern nutrition guidelines. In addition, the most common objections against the paleodiet are quoted. The subject of the paleodiet remains an open research concept whose development can influence nutrition recommendations. 相似文献
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Thomas Leisner Denis Duft Ottmar M?hler Harald Saathoff Martin Schnaiter Stefano Henin Kamil Stelmaszczyk Massimo Petrarca Rapha?lle Delagrange Zuoqiang Hao Johannes Lüder Yannick Petit Philipp Rohwetter Jér?me Kasparian Jean-Pierre Wolf Ludger W?ste 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(25):10106-10110
Potential impacts of lightning-induced plasma on cloud ice formation and precipitation have been a subject of debate for decades. Here, we report on the interaction of laser-generated plasma channels with water and ice clouds observed in a large cloud simulation chamber. Under the conditions of a typical storm cloud, in which ice and supercooled water coexist, no direct influence of the plasma channels on ice formation or precipitation processes could be detected. Under conditions typical for thin cirrus ice clouds, however, the plasma channels induced a surprisingly strong effect of ice multiplication. Within a few minutes, the laser action led to a strong enhancement of the total ice particle number density in the chamber by up to a factor of 100, even though only a 10−9 fraction of the chamber volume was exposed to the plasma channels. The newly formed ice particles quickly reduced the water vapor pressure to ice saturation, thereby increasing the cloud optical thickness by up to three orders of magnitude. A model relying on the complete vaporization of ice particles in the laser filament and the condensation of the resulting water vapor on plasma ions reproduces our experimental findings. This surprising effect might open new perspectives for remote sensing of water vapor and ice in the upper troposphere. 相似文献
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Xu Fang Wheaton Anne G. Barbour Kamil E. Liu Yong Greenlund Kurt J. 《Digestive diseases and sciences》2021,66(6):1818-1828
Digestive Diseases and Sciences - Patients with inflammatory bowel disease (IBD) have a higher risk of hip fracture, but lower likelihood of having arthroplasties than non-IBD patients in... 相似文献