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排序方式: 共有3055条查询结果,搜索用时 15 毫秒
31.
Young Beom Kwak Jundong Yu Eo Jin Im Bok Son Jeong Hye Hyun Yoo 《Drug testing and analysis》2022,14(4):718-723
Cobalt is a substance that has been abused for athletic performance enhancement and has thus been prohibited by human and animal sports doping control authorities. However, because cobalt is present in humans and animals as a trace element, a certain level of cobalt is naturally present in their excretions. In the racing industry, cobalt is a controlled substance with a threshold concentration specified by the International Agreement on Breeding, Racing and Wagering (IABRW) for international harmonization. Due to environmental and feed consumption differences among countries, regional cobalt concentration trends should be evaluated before cobalt testing is introduced. In this study, we conducted a preliminary evaluation of the urinary concentration of cobalt among a population of racehorses in Korea using inductively coupled plasma mass spectrometry (ICP-MS) analysis, followed by analysis of the urinary release of cobalt after the administration of cobalt chloride in various situations. The normal distribution for the Korea-based racehorses was used to determine a urine concentration limit (96.5 ng/ml, risk factor of 1 in 10,000). After the intravenous (IV) administration of CoCl2, the initial elimination of cobalt was rapid. A high concentration (over 2,000 ng/ml) and a slow excretion pattern were observed during the final 2 weeks of the 3-week observation period. When CoCl2 was administered orally, maximum concentration (Cmax, 92–992 ng/ml) was observed at 6–8 h. 相似文献
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Hyung Ji Cho Jung Im Jung Hwan Wook Kim Kyo Young Lee 《Korean journal of radiology》2012,13(4):500-504
We present an unusual case of an intracardiac Eustachian valve cyst observed concurrently with atresia of the coronary sinus ostium, a persistent left superior vena cava (LSVC) and a bicuspid aortic valve. There have been several echocardiographic reports of Eustachian valve cysts; however, there is no report of multidetector computed tomography (MDCT) findings related to a Eustachian valve cyst. Recently, we observed a Eustachian valve cyst diagnosed on MDCT showing a hypodense cyst at the characteristic location of the Eustachian valve (the junction of the right atrium and inferior vena cava). MDCT also demonstrated additional cardiovascular anomalies including atresia of the coronary sinus ostium and a persistent LSVC and bicuspid aortic valve. 相似文献
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Kyoung Im Cho M.D. Jae Hwan Kwon M.D. Seong Man Kim M.D. Tae Jung Park M.D. Hyeon Gook Lee M.D. Tae Ik Kim M.D. 《Echocardiography (Mount Kisco, N.Y.)》2012,29(9):1071-1080
We aimed to assess the impact of obstructive sleep apnea (OSA) on the left ventricular (LV) function independent of obesity using the myocardial performance index (Tei index) and the global longitudinal LV strain (GLS) and its reversibility after surgery. Twenty‐five newly diagnosed OSA patients, normal weight (n = 15) and obese (body mass index [BMI] ≥ 25; n = 20) controls without OSA were enrolled and underwent transthoracic echocardiographic evaluation. The OSA and obese groups had a significantly comparable increased BMI and LV chamber dimension, prolonged isovolumic relaxation time, reduced early mitral filling velocity, and increased late mitral filling velocity and Tei index as compared to the normal weight group. However, GLS was significantly reduced only in the OSA group (–16.5 ± 1.9%) as compared to the normal weight group (–20.6 ± 2.0%, P < 0.001) and obese group (–19.1 ± 2.5%, P < 0.001). As a treatment, 13 of 25 patients underwent surgical modification, and the follow‐up echocardiogram revealed significantly improved Tei index and GLS as compared to baseline (0.37 ± 0.06 and –18.9 ± 3.3% vs. 0.42 ± 0.04 and –16.3 ± 2.4%, P = 0.006 and 0.031, respectively), which was comparable to the obese controls. A reduction in the apnea‐hypopnea index had a significant effect on the improvement in the GLS (r = 0.73, P < 0.001). LV systolic and diastolic function significantly deteriorated in the patients with OSA beyond obesity, and an improvement in the LV function was observed within 6 months after the surgical modification. GLS is considered to be one of the parameters that can be used in the early detection of LV systolic dysfunction in patients with OSA and a normal ejection fraction. 相似文献
36.
Spatiotemporal microstructural white matter changes in diffusion tensor imaging after transient focal ischemic stroke in rats
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Won‐Beom Jung Yong Hee Han Julius Juhyun Chung Sun Young Chae Sung Hoon Lee Geun Ho Im JiHoon Cha Jung Hee Lee 《NMR in biomedicine》2017,30(6)
Structural reorganization in white matter (WM) after stroke is a potential contributor to substitute or to newly establish the functional field on the injured brain in nature. Diffusion tensor imaging (DTI) is an imaging modality that can be used to evaluate damage and recovery within the brain. This method of imaging allows for in vivo assessment of the restricted movements of water molecules in WM and provides a detailed look at structural connectivity in the brain. For longitudinal DTI studies after a stroke, the conventional region of interest method and voxel‐based analysis are highly dependent on the user‐hypothesis and parameter settings for implementation. In contrast, tract‐based spatial statistics (TBSS) allows for reliable voxel‐wise analysis via the projection of diffusion‐derived parameters onto an alignment‐invariant WM skeleton. In this study, spatiotemporal WM changes were examined with DTI‐derived parameters (fractional anisotropy, FA; mean diffusivity, MD; axial diffusivity, DA; radial diffusivity, RD) using TBSS 2 h to 6 weeks after experimental focal ischemic stroke in rats (N = 6). FA values remained unchanged 2–4 h after the stroke, followed by a continuous decrease in the ipsilesional hemisphere from 24 h to 2 weeks post‐stroke and gradual recovery from the ipsilesional corpus callosum to the external capsule until 6 weeks post‐stroke. In particular, the fibers in these areas were extended toward the striatum of the ischemic boundary region at 6 weeks on tractography. The alterations of the other parameters in the ipsilesional hemisphere showed patterns of a decrease at the early stage, a subsequent pseudo‐normalization of MD and DA, a rapid reduction of RD, and a progressive increase in MD, DA and RD with a decreased extent in the injured area at later stages. The findings of this study may reflect the ongoing processes on tissue damage and spontaneous recovery after stroke. 相似文献
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This study concerns obesity-related atherosclerosis, hyperlipidemia, and chronic inflammation. We studied the anti-obesity and anti-atherosclerosis effects of phenethyl isothiocyanate (PEITC) and explored their underlying mechanisms. We established an animal model of high fat/cholesterol-induced obesity in C57BL/6 mice fed for 13 weeks. We divided the mice into five groups: control (CON), high fat/cholesterol (HFCD), HFCD with 3 mg/kg/day gallic acid (HFCD + G), and HFCD with PEITC (30 and 75 mg/kg/day; HFCD + P30 and P75). The body weight, total cholesterol, and triglyceride were significantly lower in the HFCD + P75 group than in the HFCD group. Hepatic lipid accumulation and atherosclerotic plaque formation in the aorta were significantly lower in both HFCD + PEITC groups than in the HFCD group, as revealed by hematoxylin and eosin (H&E) staining. To elucidate the mechanism, we identified the expression of genes related to inflammation, reverse cholesterol transport, and lipid accumulation pathway in the liver. The expression levels of peroxisome proliferator activated receptor gamma (PPARγ), liver-X-receptor α (LXR-α), and ATP binding cassette subfamily A member 1 (ABCA1) were increased, while those of scavenger receptor A (SR-A1), cluster of differentiation 36 (CD36), and nuclear factor-kappa B (NF-κB) were decreased in the HFCD + P75 group compared with those in the HFCD group. Moreover, PEITC modulated H3K9 and H3K27 acetylation, H3K4 dimethylation, and H3K27 di-/trimethylation in the HFCD + P75 group. We, therefore, suggest that supplementation with PEITC may be a potential candidate for the treatment and prevention of atherosclerosis and obesity. 相似文献
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