• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.3
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• pp.1-7
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• 2018

As part of a research dedicated to the field evaluation of the durability of concrete subjected to freezing-thawing, this study analyzes the relationship between the surface roughness and the relative dynamic elastic modulus through image analysis. Four mix compositions with water-to-binder ratios (W/B) of 40%, 50%, 60% and 70% and without AE agent were considered to provoke early freezing. The basic physical properties of the mixes including the relative dynamic elastic modulus and the compressive strength were first evaluated experimentally according to W/B. Then, tests were performed to measure the surface roughness followed by photographs and SEM image analysis. The measured surface roughness tended to increase with larger number of freezing-thawing cycles regardless of W/B. The relative dynamic elastic modulus appeared to increase gradually with the number of cycles for the relatively denser mixes with W/B of 40% and 50%. Besides, the surface roughness increased only at rupture for the mixes with W/B of 60% and 70%. Moreover, the analysis of the photographs of the surface of the mixes with W/B of 40% and 50% revealed that the degradation progressed gradually from the surface with the freezing-thawing cycles. However, for the mixes with W/B of 60% and 70%, apparent change of the surface remained very insignificant until rupture at which damage like cracking could be observed. Consequently, the analysis of surface photograph or the measurement of the surface roughness presented some limitation in assessing the degree of freezing-thawing-induced degradation in case of relatively porous specimens. On the other hand, the photograph and surface roughness appeared to be sufficient for assessing such degradation for the mixes with W/B of 40% and 50%. Accordingly, the image of the surface and the surface roughness are potentially applicable on site for the assessment of freezing-thawing damages in relatively dense mixes.

• The Journal of Korean Medicine
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• v.31 no.1
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• pp.81-92
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• 2010

Objectives: The objective of this study was to assess bra in activation and difference by LI11 or ST36 acupuncture stimulation using functional MRI (fMRI). Methods: A total of 10 healthy right-handed volunteers were studied. LI11 acupuncture and ST36 acupuncture stimulations were applied in order on the left. The block design paradigm of RARARA was used for the task, with R representing rest and A representing stimulation, and each period lasted 30 seconds. fMRI data were analyzed using SPM2. Results: The left LI11 acupuncture stimulation activated both sides of the inferior parietal lobule, the left side of the extra-nuclear, culmen and inferior semi-lunar lobules. On the right side, the nodule and midbrain regions were activated by the left LI11 acupuncture stimulation. The left ST36 acupuncture stimulation activated the right side of the superior frontal gyrus, middle frontal gyrus, superior parietal lobule, inferior semi-lunar lobule and pyramis. On the left side, the sub-gyral, middle temporal gyrus, fusiform gyrus, supramarginal gyrus, extra-nuclear, cingulate gyrus and fastigium regions were activated by the left ST36 acupuncture stimulation. Besides, both sides of the paracentral lobule, inferior parietal lobule, culmen, cerebellar tonsil and midbrain regions were activated. Conclusions: In conclusion, brain signal activation patterns according to acupoints were observed to differ, and ST36 acupuncture stimulation activated more regions than LI11. It is supposed that LI11 and ST36 acupuncture stimulations have an influence on motor function and sensory aphasia, and these stimulations thus represent potential for ocular motor dysfunction, discriminative touch or position sense disorder. Moreover, ST36 acupuncture stimulation activated the cingulate gyrus of the limbic system, so it seems to have an influence over autonomic functions.

• The Journal of Korean Medicine
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• v.31 no.1
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• pp.130-137
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• 2010

Objectives: So far it has been reported that acupuncture increases cerebral blood supply and stimulates the functional activity of brain nerve cells. Previous studies have demonstrated that frequently used electro-acupuncture (EA) therapies for stroke increased regional cerebral blood flow (rCBF) in normal volunteers. Though ST 36-ST 41 EA is another prevailing therapy for stroke, there had been no report about its effect on rCBF. This study was to evaluate the effect of ST 36-ST 41 EA on rCBF in normal volunteers using single photon emission computed tomography (SPECT) and statistical parametric mapping (SPM). Methods: In the resting state, $^{99m}Tc$-ECD brain SPECT scans were performed on 10 normal volunteers (5 males, 5 female, mean age $23.6{\pm}0.5$ years). On the other study day, 7 days after the resting examination, 15 minutesEA were applied at ST 36 and ST 41 on the right side of the subjects. Immediately after ST36-ST41 EA, the second SPECT images were obtained in the same manner as the resting state. Significant increases and decreases of rCBF after EA were estimated by comparing their SPECT images with those of the resting state using paired t statistics at every voxel, which were analyzed by SPM with a threshold of p = 0.01, uncorrected (extent threshold: k=100 voxels). Results: EA applied at the right ST36-ST41 significantly increased rCBF in the right inferior parietal lobule (Brodmann area [BA] 40), right retrosubicular area (BA 48), left inferior parietal lobule (BA 40), left middle temporal gyrus (BA 21), left fusiform gyrus (BA 37), left inferior parietal lobule (BA 39), left inferior temporal gyrus (BA 20), and left somatosensory association cortex (BA 7). However, right ST36-ST41 EA significantly decreased rCBF in the right parahippocampal gyrus (BA 35), right cerebellum, left frontopolar area (BA 10), left orbitofrontal area (BA 11), left dorsolateral prefrontal cortex (BA 9), and left dorsal anterior cingulate cortex (BA 32). Conclusions: These results demonstrate that rightST36-ST41 EA increased rCBF prominently in both inferior parietal lobule (BA 40) and right retrosubicular area (BA 48), which suggest that there be correlation between specific EA and corresponding rCBF.

• Journal of Korean Ophthalmic Optics Society
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• v.7 no.1
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• pp.39-43
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• 2002

This study was investigated the anti-angiogenic activities of Cnidium officinale Makino and Tabanus bovinus by using Chorioallantoic membrane (CAM) and rat cornea. First experiment, the fertilized chicken eggs were kept in a humidified egg incubator at $37^{\circ}C$. After 4 days incubation, about 3 ml of albumin was aspirated from eggs with an hypodermic needles through a small hole drilled at the narrow end of the eggs, and the shell membrane on the floor of the air sac was peeled away. Embryos with chorioallantois of 3~5 mm in diameter were employed for the assay of antiangiogenic activity. Retinoic acid was used as a positive control for this experiment. After 48 h of treatment. branching pattern of blood vessels below coverslip containing retinoic acid ($10{\mu}g/egg$) was dramatically decreased. A simiar angiogenic inhibition was observed in the CAM treated with $50{\mu}g/egg$ of Cnidium omcinale Makino and Tabanus bovinus extracts. Second experiment, rat corneal neovascularization was induced by suturing (one stitch) the cornea with 10-0 nylon, and terramycin was applied on the cornea for I week to prevent corneal inflammation. In the cornea of rats untreated with herbal extracts, numerous vessels were usually seen invading the cornea by day 2 or 3 after suture, and reaching the lesion area within 5~6 days. Corneal neovascularization was gradually increased and peaked at 3 weeks. In contrast to this, herbal extracts conspicuously inhibited the angiogenesis, Oral administration of herbal extracts (20 mg/kg body weight/day) for 4 weeks significantly inhibited the rat corneal angiogenesis induced by suture, and the length of blood vessels in herbal medicine-treated rat cornea was conspicuously lower than that in control animals. A similar phenomenon was also observed in the rat cornea treated with thalidomide (200 mg/kg body weight/day). These findings indicate the anti-angiogenic properties of Cnidium officinale Makino and Tabanus bovinus, suggesting that these properties may be one of the pharmacological mechanisms underlying the anti-tumor and anti-metastatic activities of herbal extracts tested in this study.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.1
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• pp.71-82
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• 2005

The aim of this study was to provide fundamental data for the factors influencing the asthenopia of emmetropia with phoria and alleviation of asthenopia. A total of 348 subjects, aged between 19 and 30 years old, who had no strabismus, an eye trouble or whole body disease, were examined using corrected visual acuity, corrected diopter, stereopsis and suppression tests from September of 2002 to September of 2004. We excluded 21 subjects for the following reasons: if they had an amblyopia affecting binocular vision or inaccurate data. After these exclusions, 327 subjects remained. We then individually measured the refractive error correction, pupillary distance, optical center distance, phoria, convergence, accommodation and the AC/A as well as the asthenopia during binocular vision using a questionnaire. After analysis of factors affecting asthenopia, we also examined the reductive effect of a prism on the asthenopia in subjects who had asthenopia. To determine the factors affecting asthenopia during binocular vision, statistic analyses were carried out using the Chi-square test and the multivariate Logistic regression model. The results of this study were as follow. For asthenopia during near binocular vision of emmetropia with phoria, in case of the lower the accommodation and convergence, a significantly higher rate of asthenopia was observed (p<0.001). When the AC/A is lower, the higher the rate of asthenopia was observed but not significantly and there was no association between phoria and asthenopia. When the multivariate logistic regression model was used to determine factors affecting binocular vision of emmetropia with phoria, in case of the lower accommodation and convergence, a significantly higher rate of asthenopia was observed. when the phoria is esophoria or higher exophoria, or when the AC/A is lower than normal, the higher the rate of asthenopia was observed but not significantly and there was no association between phoria. AC/A and asthenopia. Therefore accommodation and convergence could be predictive factors for asthenopia during near distance binocular vision. Prism was used among' subjects who had asthenopia during near distance binocular vision, the symptom of asthenopia was eased up to 74.2% in emmetropia with phoria.

• Clinical and Experimental Pediatrics
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• v.45 no.11
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• pp.1325-1331
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• 2002

Purpose : We tried to check the accuracy of references in the Journal of the Korean Pediatric Society and Journals of the Korean Pediatric Subspecialty Societies. We also wanted to know the citation patterns of authors by analyzing the frequency of cited materials. Methods : Three journals were randomly selected from the 2000 issues of Journal of the Korean Pediatric Society and nine journals were selected mainly from the second half of 2000 issues of each Journal of the Korean Pediatric Subspecialty Societies for the study. Then the accuracy of references was checked with Medline. Journals before 1964, books, and journals which were not written in English were used only in the citation pattern analysis. Results : Author errors were the most common(21.3%) among the reference elements. The next was title errors, followed by page errors, journal errors, volume errors and year errors. Total average error rate was 34.7% and we were unable to find journals in 89 cases(2.2%). The journal of the Korean Society of Neonatology had the lowest error rate(17.4%) and the journal of the Korean Pediatric Cardiology Society had the highest error rate(53.2%). The reference journals which were published and quoted in the most recent three years were only 612 cases(15%). Foreign journals were selected as reference(78.4%) more than domestic journals; The Journal of the Korean Pediatric Society was the most frequently cited reference(43.3%) among domestic journals. Conclusion : Authors are ultimately responsible for the accuracy of references and they should check the reference list with responsibility. Hopefully, authors also will have to use more domestic journals and recent journals.

• Clinical and Experimental Pediatrics
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• v.46 no.10
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• pp.1003-1007
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• 2003

Purpose : To review the seizure-related complaints and analyze the relationship between admission rates and clinical features in children who had visited the emergency department with seizures. Methods : Retrospectively, we reviewed 180 patients(male 100, female 80) suffering from seizures, who had visited to the emergency department of Chosun University Hospital from January 2000 to June 2002. We have analyzed the correlation between admission rate and clinical features such as age, seizure type, seizure duration and individual laboratory findings(CT or MRI, and CSF). Results : Out of 4,865 total children who visited the emergency department, 180 patients(3.7%) were seizure related. The most common seizure type was simple febrile seizure(52.2%). The admission rate of children with seizures was 48.9%. The admission rate according to age, sex and abnormal laboratory findings revealed no significant correlations(P>0.05). There was a significant correlation between admission and both status epilepticus 82.4%(14/17) and complex febrile seizure 63.6%(14/22) (P<0.05). According to the duration of convulsions, admission rates were 41.2% when within five minutes, 60% when six-15 minutes, 58.8% when 16-30 minutes, 85.7% when 30 minutes, to one hour and 66.7% when above one hour of duration. According to the seizure frequency, admission rates of recurrent seizure patients(61.4%=43/70) was higher compared to the first time seizure patients(40.9%=45/110). Conclusion : We found that the admission rate of children visiting the emergency department for seizure treatment was 48.9% and significantly correlated with duration, type and frequency of seizure.

• Clinical and Experimental Pediatrics
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• v.46 no.10
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• pp.996-1002
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• 2003

Purpose : In Rett syndrome patients, the incidence of sudden death is greater than that of the general population, and cardiac electrical instability including fatal cardiac arrhythmia is a main suspected cause. In this study, we are going to find out the possible cause of the higher risk of sudden death in Rett patients by the evaluation of heart rate variability, a marker of cardiac autonomic activity and corrected QT intervals. Methods : Diagnosis of Rett syndrome was made by molecular genetic study of Rett syndrome (MECP2 gene) or clinical diagnostic criteria of Rett syndrome. Heart rate variability and corrected QT intervals were measured by 24 h-Holter study in 12 Rett patients, and in 30 age-matched healthy children with chief complaints of chest pain or suspected heart murmurs. The were compared with the normal age-matched control. Results : Patients with total Rett syndrome, classic Rett syndrome, and Rett variants had significantly lower heart rate variability(especially rMSSD)(P<0.05) and longer corrected QT intervals than age-matched healthy children(P<0.05). Sympathovagal balance expressed by the ratio of high to low frequency(LF/HF ratio) also showed statistically significant differences between the three groups considered(P<0.05). Conclusion : A significant reduction of heart rate variability, a marker of autonomic disarray, suggests a possible explanation of cardiac dysfunction in sudden death associated with Rett syndrome.

• Clinical and Experimental Pediatrics
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• v.46 no.10
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• pp.989-995
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• 2003

Purpose : Dexamethasone is frequently administered to prevent or treat chronic lung disease in human neonates who are also prone to hypoxic-ischemic(HI) insults. Recently, meta-analysis of the follow-up studies reveals a significantly increased odd ratio for the occurrence of cerebral palsy or an abnormal neurologic outcome, and there is conflicting evidence regarding the impact of dexamethasone exposure on HI brain injury. This study was conducted to explore the effect of post-HI dexamethasone administration on neuronal injury in neonatal rats. Methods : HI was produced in seven-day-old rats by right carotid artery ligation followed by two hours of 8% oxygen exposure. At the end of HI, the animals were injected intraperitoneally either with dexamethasone(0.5 mg/kg) or saline. Neuronal injury was assessed seven days after the HI by the area of infarction, TUNEL reactivity, Bcl-2 and Bax expression in brain. Results : Post-insult dexamethasone administration resulted in reduction of weight gain and a higher mortality rate during seven days after HI. Dexamethasone treatment revealed no effect on the size of brain infarction induced by HI. Bax protein expression increased in dexamethasone treated brain but Bcl-2 protein expression and TUNEL reactivity revealed no significant differences between dexamethasone treated and non treated brain. Increased Bax protein expression suggest upregulation of the apoptosis by dexamethasone. Conclusion : The result suggests the adverse role of Post-HI administration of dexamethasone in neonatal HI.

• Clinical and Experimental Pediatrics
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• v.53 no.4
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• pp.532-537
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• 2010

Purpose : Early postoperative arrhythmias are a major cause of mortality and morbidity after open heart surgery in the pediatric population. We evaluated the incidence and risk factors of early postoperative arrhythmias after surgery of congenital heart disease. Methods : From January 2002 to December 2008, we retrospectively reviewed the medical records of the 561 patients who underwent cardiac surgery in Kyungpook National University Hospital. We analyzed patients' age and weight, occurrence and type of arrhythmia, cardiopulmonary bypass (CPB) time, aortic cross clamp (ACC) time, and postoperative electrolyte levels. Results : Arrhythmias occurred in 42 of 578 (7.3%) cases of the pediatric cardiac surgery. The most common types of arrhythmia were junctional ectopic tachycardia (JET) and accelerated idioventricular rhythm (AIVR), which occurred in 17 and 13 cases, respectively. The arterial switch operation (ASO) of transposition of the great arteries (TGA) had the highest incidence of arrhythmia (36.4%). Most cases of cardiac arrhythmia showed good response to management. Patients with early postoperative arrhythmias had significantly lower body weight, younger age, and prolonged CPB and ACC times ($P$<0.05) than patients without arrhythmia. Although the mean duration of ventilator care and intensive care unit stay were significantly longer ($P$<0.05), the mortality rate was not significantly different among the 2 groups. Conclusion : Early postoperative arrhythmias are a major complication after pediatric cardiac surgery; however, aggressive and immediate management can reduce mortality and morbidity.