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101.
Moon WK Chang KH Weinmann HJ Koh YH Im JG Yeon KM Han MC 《AJR. American journal of roentgenology》2000,174(5):1385-1390
OBJECTIVE: The objective of this study was to compare enhancement patterns of a blood-pool contrast agent, Gadomer-17, with those of gadopentetate dimeglumine in bacterial abscesses and VX2 carcinoma in rabbits. MATERIALS AND METHODS: Fourteen rabbits with experimentally induced bacterial abscesses and VX2 carcinoma in both thighs underwent dynamic contrast-enhanced MR imaging with Gadomer-17 and gadopentetate dimeglumine at a 24-hr interval. The enhancement ratios (postcontrast to precontrast signal intensities) of lesions in the same animal were assessed and correlated with microvessel density. RESULTS: For Gadomer-17, the enhancement ratio of the abscesses (1.66 +/- 0.39) peaked 15 min after the injection, while that of the carcinoma (2.05 +/- 0.16) peaked at 10 min. The enhancement ratios of the carcinoma were consistently higher than those of the abscesses up to 30 min. For gadopentetate dimeglumine, peak enhancement ratio of the abscesses (2.30 +/- 0.75) was seen 5 min after the injection, while that of the carcinoma (2.32 +/- 0.51) was seen at 3 min. The enhancement ratios of the carcinomas were significantly higher at 1 min, but significantly lower at 20-30 min, compared with those of the abscesses, as a result of rapid decrease of enhancement ratios in the carcinomas. The microvessel density was 9.8 +/- 5.2 vessels per field of view for the abscesses and 36.3 +/- 9.5 vessels per field of view for the carcinoma (p < 0.001). CONCLUSION: Delayed peak enhancement and slow decay were found in both bacterial abscess and VX2 carcinoma with Gadomer-17, whereas early peak enhancement and rapid decay were found especially in VX2 carcinoma with gadopentetate dimeglumine. Enhancement ratios on MR imaging with a blood-pool contrast agent correlated well with the microvessel density in bacterial abscess and VX2 carcinoma. 相似文献
102.
Han DH Kwon OK Byun BJ Choi BY Choi CW Choi JU Choi SG Doh JO Han JW Jung S Kang SD Kim DJ Kim HI Kim HD Kim MC Kim SC Kim SC Kim Y Kwun BD Lee BG Lim YJ Moon JG Park HS Shin MS Song JH Suk JS Yim MB;Korean Society for Cerebrovascular Disease 《Acta neurochirurgica》2000,142(11):1263-73; discussion 1273-4
A co-operative study was conducted to determine the clinical characteristics of patients with moyamoya disease who were diagnosed and treated at neurosurgical institutes in Korea before 1995. Twenty-six hospitals contributed 505 cases and among them, the clinical characteristics of 334 patients with definite moyamoya disease were evaluated. The number of patients began to increase from the late 1980s, and after that approximately 20 patients were treated each year. There were two age peaks: from six to 15 and from 31 to 40 years of age. Haemorrhagic manifestations occurred in approximately 43% of the patients. The major clinical manifestations were haemorrhage in adults (62.4%) and ischaemia in children (61.2%). Overall 54.5% of the patients experienced decreased consciousness levels, mainly due to intracranial haemorrhage or cerebral infarction. In the patients with ischemic manifestations, the adult patients were more likely to have cerebral infarction than the pediatric patients (80% vs. 39%) and the pediatric patients were more likely to have TIA (61% vs. 25%). Thirty eight percent of the patients underwent bypass surgery and 53% of these procedures were performed bilaterally. Treatment policies, including indications for bypass surgery and commonly used drugs, were somewhat different according to the institution. Overall favorable outcome was 73%, and the most significant factor affecting poor outcome was haemorrhagic manifestation. This article describes the characteristics of 334 patients with moyamoya disease, who were diagnosed and treated at neurosurgical institutes in Korea before 1995. 相似文献
103.
Ja-Won Koo Il Joon Moon Woo Sub Shim So Young Moon Ji Soo Kim 《Otology & neurotology》2006,27(3):367-371
BACKGROUND: Horizontal canal benign paroxysmal positional vertigo is characterized by horizontal direction-changing nystagmus induced by lateral head turning in supine position. According to Ewald's second law, the direction of head turning that creates a stronger response represents the affected side in geotropic nystagmus and the healthy side in apogeotropic nystagmus. However, it may not always be possible to lateralize the involved ear only by comparing the intensity of the nystagmus. We studied the values of nystagmus induced by position change from sitting to supine in the lateralization of horizontal canal benign paroxysmal positional vertigo. METHODS: A retrospective study of 54 patients who had been diagnosed as having horizontal canal benign paroxysmal positional vertigo at the Dizziness Clinic of Seoul National University Bundang Hospital from May 2003 to February 2004 was performed. The directions of the nystagmus induced by lying down were compared with those determined by Ewald's second law. RESULTS: Of the 54 patients, 32 (20 apogeotropic and 12 geotropic) showed horizontal nystagmus induced by lying down. The nystagmus tended to be ipsilesional in apogeotropic patients (80%) and contralesional in their geotropic counterparts (75%). CONCLUSION: In horizontal canal benign paroxysmal positional vertigo, lying-down nystagmus mostly beats toward the involved ear in the apogeotropic type and directs to the healthy ear in the geotropic type. The direction of lying-down nystagmus may help lateralizing the involved ear in horizontal canal benign paroxysmal positional vertigo. 相似文献
104.
Cheol Park Eun Ok Choi Hyun Hwangbo Hyesook Lee Jin-Woo Jeong Min Ho Han Sung-Kwon Moon Seok Joong Yun Wun-Jae Kim Gi-Young Kim Hye-Jin Hwang Yung Hyun Choi 《Nutrition Research And Practice》2022,16(3):330
BACKGROUND/OBJECTIVESZanthoxylum schinifolium is traditionally used as a spice for cooking in East Asian countries. This study was undertaken to evaluate the anti-proliferative potential of ethanol extracts of Z. schinifolium leaves (EEZS) against human bladder cancer T24 cells.MATERIALS/METHODSSubsequent to measuring the cytotoxicity of EEZS, the anti-cancer activity was measured by assessing apoptosis induction, reactive oxygen species (ROS) generation, and mitochondrial membrane potential (MMP). In addition, we determined the underlying mechanism of EEZS-induced apoptosis through various assays, including Western blot analysis.RESULTSEEZS treatment concentration-dependently inhibited T24 cell survival, which is associated with apoptosis induction. Exposure to EEZS induced the expression of Fas and Fas-ligand, activated caspases, and subsequently resulted to cleavage of poly (ADP-ribose) polymerase. EEZS also enhanced the expression of cytochrome c in the cytoplasm by suppressing MMP, following increase in the ratio of Bax:Bcl-2 expression and truncation of Bid. However, EEZS-mediated growth inhibition and apoptosis were significantly diminished by a pan-caspase inhibitor. Moreover, EEZS inhibited activation of the phosphoinositide 3-kinase (PI3K)/Akt pathway, and the apoptosis-inducing potential of EEZS was promoted in the presence of PI3K/Akt inhibitor. In addition, EEZS enhanced the production of ROS, whereas N-acetyl cysteine (NAC), a ROS scavenger, markedly suppressed growth inhibition and inactivation of the PI3K/Akt signaling pathway induced by EEZS. Furthermore, NAC significantly attenuated the EEZS-induced apoptosis and reduction of cell viability.CONCLUSIONSTaken together, our results indicate that exposure to EEZS exhibits anti-cancer activity in T24 bladder cancer cells through ROS-dependent induction of apoptosis and inactivation of the PI3K/Akt signaling pathway. 相似文献
105.
Yoon Jin Choi Yong Chan Lee Jung Mogg Kim Jin Il Kim Jeong Seop Moon Yun Jeong Lim Gwang Ho Baik Byoung Kwan Son Hang Lak Lee Kyoung Oh Kim Nayoung Kim Kwang Hyun Ko Hye-Kyung Jung Ki-Nam Shim Hoon Jai Chun Byung-Wook Kim Hyuk Lee Jie-Hyun Kim Hyunsoo Chung Sang Gyun Kim Jae Young Jang 《Gut and liver》2022,16(4):535
Background/AimsWe examined the efficacy and safety of tegoprazan as a part of first-line triple therapy for Helicobacter pylori eradication.MethodsA randomized, double-blind, controlled, multicenter study was performed to evaluate whether tegoprazan (50 mg)-based triple therapy (TPZ) was noninferior to lansoprazole (30 mg)-based triple therapy (LPZ) (with amoxicillin 1 g and clarithromycin 500 mg; all administered twice daily for 7 days) for treating H. pylori. The primary endpoint was the H. pylori eradication rate. Subgroup analyses were performed according to the cytochrome P450 (CYP) 2C19 genotype, the minimum inhibitory concentration (MIC) of amoxicillin and clarithromycin, and underlying gastric diseases.ResultsIn total, 350 H. pylori-positive patients were randomly allocated to the TPZ or LPZ group. The H. pylori eradication rates in the TPZ and LPZ groups were 62.86% (110/175) and 60.57% (106/175) in an intention-to-treat analysis and 69.33% (104/150) and 67.33% (101/150) in a per-protocol analysis (non-inferiority test, p=0.009 and p=0.013), respectively. Subgroup analyses according to MICs or CYP2C19 did not show remarkable differences in eradication rate. Both first-line triple therapies were well-tolerated with no notable differences.ConclusionsTPZ is as effective as proton pump inhibitor-based triple therapy and is as safe as first-line H. pylori eradication therapy but does not overcome the clarithromycin resistance of H. pylori in Korea (ClinicalTrials.gov identifier ). NCT03317223相似文献
106.
Won Myung Lee Jong Ho Moon Yun Nah Lee Il Sang Shin Tae Hoon Lee Jae Kook Yang Sang-Woo Cha Young Deok Cho Sang-Heum Park 《Gut and liver》2022,16(4):599
Background/AimsTreatment options for difficult bile duct stones are limited. Direct peroral cholangioscopy (POC)-guided lithotripsy may be an option. A newly developed multibending (MB) ultraslim endoscope has several structural features optimized for direct POC. We evaluated the utility of direct POC using an MB ultraslim endoscope for lithotripsy in patients with difficult bile duct stones.MethodsTwenty patients with difficult bile duct stones, in whom stone removal using conventional endoscopic methods, including mechanical lithotripsy, had failed were enrolled from March 2018 to August 2019. Direct POC-guided lithotripsy was performed by electrohydraulic lithotripsy or laser lithotripsy. The primary outcome was complete ductal clearance, defined as the retrieval of all bile duct stones after lithotripsy confirmed by balloon-occluded cholangiography and/or direct POC.ResultsThe technical success rate of direct POC was 100% (20/20), and the free-hand insertion rate was 95% (19/20). Direct POC-guided lithotripsy, attempted by electrohydraulic lithotripsy in nine patients (45%) and laser lithotripsy in 11 patients (55%), was successful in 95% (19/20) of the patients. Complete ductal clearance after direct POC-guided lithotripsy was achieved in 95% (19/20) of patients. Patients required a median of 2 (range, 1–3) endoscopic retrograde cholangiopancreatography sessions for complete stone removal. Adverse event was observed in one patient (5%) with hemobilia and was treated conservatively.ConclusionsDirect POC using an MB ultraslim endoscope was safe and effective for lithotripsy in patients with difficult bile duct stones. 相似文献
107.
108.
Rationale:Oblique lumbar interbody fusion (OLIF) is an effective and safe surgical technique widely used for treating spondylolisthesis; however, its use is controversial because of several associated complications, including endplate injury. We report a rare vertebral body fracture following OLIF in a patient with poor bone quality.Patient concerns:A 72-year-old male patient visited our clinic for 2 years with lower back pain, leg radiating pain, and intermittent neurogenic claudication.Diagnoses:Lumbar magnetic resonance imaging revealed L4-5 stenosis.Intervention:We performed OLIF with percutaneous pedicle screw fixation and L4 subtotal decompressive laminectomy. We resected the anterior longitudinal ligament partially for anterior column release and inserted a huge cage to maximize segmental lordosis. No complications during and after the operation were observed. Further, the radiating pain and back pain improved, and the patient was discharged. Two weeks after the operation, the patient visited the outpatient department complaining of sudden recurred pain, which occurred while going to the bathroom. Radiography and computed tomography revealed a split fracture of the L5 body and an anterior cage displacement. In revision of OLIF, we removed the dislocated cage and filled the bone cement between the anterior longitudinal ligament and empty disc space. Further, we performed posterior lumbar interbody fusion L4-5, and the screw was extended to S1.Outcomes:After the second surgery, back pain and radiating pain in the left leg improved, and he was discharged without complications.Lesson:In this case, owing to insufficient intervertebral space during L4-5 OLIF, a huge cage was used to achieve sufficient segmental lordosis after anterior column release, but a vertebral body coronal fracture occurred. In patients with poor bone quality and less flexibility, a huge cage and over-distraction could cause a vertebral fracture; hence, selecting an appropriate cage or considering a posterior approach is recommended. 相似文献
109.
Kakyeong Kim Yoonjung Yoonie Joo Gun Ahn HeeHwan Wang SeoYoon Moon Hyeonjin Kim WooYoung Ahn Jiook Cha 《Human brain mapping》2022,43(12):3857
Sex impacts the development of the brain and cognition differently across individuals. However, the literature on brain sex dimorphism in humans is mixed. We aim to investigate the biological underpinnings of the individual variability of sexual dimorphism in the brain and its impact on cognitive performance. To this end, we tested whether the individual difference in brain sex would be linked to that in cognitive performance that is influenced by genetic factors in prepubertal children (N = 9,658, ages 9–10 years old; the Adolescent Brain Cognitive Development study). To capture the interindividual variability of the brain, we estimated the probability of being male or female based on the brain morphometry and connectivity features using machine learning (herein called a brain sex score). The models accurately classified the biological sex with a test ROC–AUC of 93.32%. As a result, a greater brain sex score correlated significantly with greater intelligence (p fdr < .001, = .011–.034; adjusted for covariates) and higher cognitive genome‐wide polygenic scores (GPSs) (p fdr < .001, < .005). Structural equation models revealed that the GPS‐intelligence association was significantly modulated by the brain sex score, such that a brain with a higher maleness score (or a lower femaleness score) mediated a positive GPS effect on intelligence (indirect effects = .006–.009; p = .002–.022; sex‐stratified analysis). The finding of the sex modulatory effect on the gene–brain–cognition relationship presents a likely biological pathway to the individual and sex differences in the brain and cognitive performance in preadolescence. 相似文献
110.
Joo Won Han Jihyun Park Jung Ha Kim Siti Aisyah Nurmaulia Entifar Ajeng Prameswati Anky Fitrian Wibowo Soyeon Kim Dong Chan Lim Jonghee Lee Myoung-Woon Moon Min-Seok Kim Yong Hyun Kim 《Materials》2022,15(14)
Conductive composite materials have attracted considerable interest of researchers for application in stretchable sensors for wearable health monitoring. In this study, highly stretchable and conductive composite films based on carboxymethyl cellulose (CMC)-poly (3,4-ethylenedioxythiopehe):poly (styrenesulfonate) (PEDOT:PSS) (CMC-PEDOT:PSS) were fabricated. The composite films achieved excellent electrical and mechanical properties by optimizing the lab-synthesized PEDOT:PSS, dimethyl sulfoxide, and glycerol content in the CMC matrix. The optimized composite film exhibited a small increase of only 1.25-fold in relative resistance under 100% strain. The CMC-PEDOT:PSS composite film exhibited outstanding mechanical properties under cyclic tape attachment/detachment, bending, and stretching/releasing tests. The small changes in the relative resistance of the films under mechanical deformation indicated excellent electrical contacts between the conductive PEDOT:PSS in the CMC matrix, and strong bonding strength between CMC and PEDOT:PSS. We fabricated highly stretchable and conformable on-skin sensors based on conductive and stretchable CMC-PEDOT:PSS composite films, which can sensitively monitor subtle bio-signals and human motions such as respiratory humidity, drinking water, speaking, skin touching, skin wrinkling, and finger bending. Because of the outstanding electrical properties of the films, the on-skin sensors can operate with a low power consumption of only a few microwatts. Our approach paves the way for the realization of low-power-consumption stretchable electronics using highly stretchable CMC-PEDOT:PSS composite films. 相似文献