• Korean Journal of Poultry Science
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• v.18 no.3
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• pp.183-196
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• 1991

In order to establish ELISA method to detect antibody against IBV various factors involved were examined. Antigen was prepared from Massachusetts type IBV which is known to be one of serotypes distributed most widely. The virus was grown in embryonated SPF chicken eggs. Allantoic fluid harvested was processed to ultracentrifugation and sucrose density gradient centrifugation to produce a purified antigen The antisera selected from the field samples based on hemagglutination inhibition test were used as the standard positive and negative sera for this study and the results obtained were summarized as follows. 1 , It was found that ELISA test was satisfactory when the purified antigen was coated on the plate in the amount of about 40ng protein per well. In case of the phospholipase treated hemagglutinating antigen it gave satisfactory results when the each well wns coated with 1.2 to 2.5 hemagglutinating unit which was equivalent to 40 to 90ng of protein. 2. There was no significant difference in the ratio of optical density of positive to that of negative serum whether the coated antigen was held for 1 hour at 37$^{\circ}C$ or it was held overnight at 4$^{\circ}C$. The coated antigen could be kept in dried state without change of antigenecity for at least one month of experimental period at 4$^{\circ}C$. 3. There was a big variation in the optical density and P/N values depending on the maker of the plates and on the plate of the same maker. 4. It was found that background optical density was negligible when serum was diluted more than 1：50 and serum dilution of 1：100 appeared to be appropriate as a routine test dilution to screen the antibody. 5. Optical density was fairly constant 15 minutes afterward from the time substrate was treated and during the 4 hours after stopper was treated. 6. There was a low correlation(r＝0.42) between ELISA and HI test. However, when 74serum samples were tested for the IBV antibody, 98.7% were found to be positive by both tests in which titers of 2$^{6}$ or more by HI test and P/N values of 1.4 or more by ELISA were considered to be positive, 7 Day-old IBV vaccinated chickens shows a similar antibody decay and rising pattern until 8 weeks of age by the two tests, ELISA and HI.

• Clinical and Experimental Pediatrics
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• v.48 no.1
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• pp.68-74
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• 2005

Purpose : There is growing use of continuous renal replacement therapy(CRRT) for pediatric patients, but reports about the use and outcome of CRRT in children is rare in Korea. We report our experiences of CRRT in critically ill pediatric patients. Methods : We reviewed the medical records of 23 pediatric patients who underwent CRRT at Asan Medical Center between May 2001 and May 2004. We evaluated underlying diseases, clinical features, treatment courses, CRRT modalities and outcomes. Results : Ages ranged from three days to 16 years with a median of five years. Patients weighed 2.4 to 63.9 kg(median 23.0 kg; 10 patients ${\leq}20kg$). The underlying diseases were malignancy(nine cases), multiple organ dysfunction syndrome(five cases), hyperammonemia(four cases), acute renal failure associated with liver failure(three cases), dilated cardiomyopathy(one case) and congenital nephrotic syndrome(one case). Pediatric Risk of Mortality(PRISM) III score was $17.6{\pm}7.6$ and the mean number of failing organs was $3.0{\pm}1.7$. Duration of CRRT was one to 27 days(median : nine days). Eleven patients(47.8%) survived. Chronic renal failure developed in two cases, intracranial hemorrhage in one case, and chylothorax in one case among the survivors. PRISM III score and the number of vasopressor before the start of CRRT was significantly lower in the survivors($12.7{\pm}4.2$ and $0.9{\pm}1.1$) compared with nonsurvivors($22.1{\pm}7.8$ and $2.4{\pm}1.4$)(P<0.05). Conclusion : CRRT driven in venovenous mode is an effective and safe method of renal support for critically-ill infants and children to control fluid balance and metabolic derangement. Survival is affected by PRISM III score and the number of vasopressors at the initiation of CRRT.

• Clinical and Experimental Pediatrics
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• v.49 no.5
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• pp.533-538
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• 2006

Purpose : The headache, one of the symptoms of meningitis, is related to abrupt elevation of intracranial pressure(ICP) or stimulation of intracranial nociceptive structure. However, in cases of mild elevation of ICP or normal findings of cerebrospinal fluid(CSF) analysis, patients sometimes complain of headaches. Therefore, other pathways may contribute to the occurrence of headaches in aseptic meningitis or meningismus. We intend to investigate the role of substance P(SP) and calcitonin gene-related peptide(CGRP) in aseptic meningitis or meningismus. Methods : We measured leukocyte count, the concentration of protein and glucose in CSF and ICP of patients with meningeal irritation sign. We also measured SP and CGRP levels by using immunoassay. We analyzed the relationship between the presence of headache and the value of SP and CGRP. Results : The concentrations of CGRP($18.8{\pm}10.5ng/mL$) in CSF and ICP($14.8{\pm}4.5cmH_2O$) in aseptic meningitis group were significantly higher than in those($14.1{\pm}7.4ng/mL$ and $12.0{\pm}5.1cmH_2O$, respectively) of the meningismus group(P<0.05). There was no significant difference in the SP levels between the two groups. In the aseptic meningitis group, the concentrations of SP and CGRP were significantly higher in the normal ICP group than in the elevated ICP group(P<0.05). Conclusion : Headaches in children with aseptic meningitis or meningismus is considered to be related to the elevation of the CSF levels of SP and CGRP.

• Clinical and Experimental Pediatrics
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• v.48 no.7
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• pp.753-759
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• 2005

Purpose : This study was performed to characterize clinical features of benign convulsions with gastroenteritis(CwG) in infants. Methods : We reviewed clinical features of 67 episodes in 64 patients with afebrile seizure accompanied gastroenteritis admitted to Dept. of Pediatrics Bundang CHA hospital from January 2001 to June 2004. Patients with meningitis, encephalitis/encephalopathy or apparent history of epilepsy were excluded. Results : There were 32 boys and 35 girls. The age of onset ranged from 1 to 42 months($18.5{\pm}6.1$ months). The number of children admitted to the hospital with acute gastroenteritis was 2,887 in the same period. The percentage of patients with CwG was 2.3. Seizure type was exclusively generalized tonic or tonic-clonic seizure. The average number of seizures during a single episode was 3.1 (range, 1-13). Two or more seizures occurred in 53(79.1%) of the 67 episodes. Antiepileptic drugs were administered for 42 episodes. Seizure did not cease after the administration of one kind of antiepileptic drug in 23 episodes(54.7%). The seizures were rather refractory to initial antiepileptic treatment. There were no abnormalities in serum biochemistry test including glucose and electrolytes. Cerebrospinal fluid was normal in all 54 episodes. Stool cultures were negative in 49 episodes. Rotavirus was positive in stools in 51(82.3%) of 62 episodes. Norovirus was positive in stools in 2 episodes and astrovirus in 1 of 18 episodes. CT and/or MRI were performed in 15 cases and demonstrated no neuroradiologic abnormalities. Of 73 Interictal EEG, initial 24 cases showed occasional spike or sharp wave discharges from the mid-line area during stage I-II sleep, which were apparently differentiated from vertex sharp transient or K-complexes. The mean follow-up period was 5.7 months(1-36 months). Three patients experienced a recurrence of CwG, but all patients exhibited normal psychomotor development at the last follow-up. Conclusion : Afebrile infantile convulsions with gastroenteritis are brief generalized seizure in cluster with normal laboratory findings and good prognosis. Therefore CwG is likely to be categorized as situation-related seizure of special syndrome. Recognition of this entity should lead to assurance of the parents and long-term anticonvulsant therapy is not usually warranted.

• Clinical and Experimental Pediatrics
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• v.46 no.8
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• pp.789-794
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• 2003

Purpose : We intended to evaluate the effect of hypoxia-ischemia on extracellular striatal monoamine metabolism in neonatal rat brains by in vivo microdialysis. Methods : The right common carotid arteries of five or six-day old rats were surgically ligated, and the probes for microdialysis were inserted into the right striatum with stereotaxic instrument. After stabilization for two hours, artificial cerebrospinal fluid was infused via the probe for microdialysis and samples were collected during hypoxia-ischemia and recovery periods at 20 minute intervals. The concentrations of DA(dopamine), DOPAC(3,4-di-hydroxyphenyl acetic acid), HVA(homovanillic acid), NE(norepinephrine), and 5-HIAA(5-hydroxy indole-acetic acid) were measured by HPLC(high performance liquid chromatography) and the changes were analysed. Results : The striatal levels of dopamine metabolites such as DOPAC and HVA, were significantly decreased during hypoxia-ischemia, and increased to their basal level during reoxygenation(P<0.05). Dopamine mostly increased during hypoxia but statistically not significant(P>0.05). DOPAC showed the most remarkable decrease($23.0{\pm}4.2%$, P<0.05), during hypoxia-ischemia and increase to the basal levels during reoxygenation($120.8{\pm}54.9%$, P<0.05), and HVA showed the same pattern of changes as those of DOPAC during hypoxia-ischemia($35.3{\pm}7.6%$ of basal level, P<0.05) and reoxygenation ($105.8{\pm}32.3%$). However, the level of NE did not show significant changes during hypoxia-ischemia and reoxygenation. The levels of 5-HIAA decreased($74.9{\pm}3.1%$) and increased($118.1{\pm}7.8%$) during hypoxia-ischemia and reoxygenation, respectively(P<0.005). Conclusion : Hypoxia-ischemia had a significant influence on the metabolism of striatal monoamine in neonatal rat brains. These findings suggest that monoamine, especially dopamine, and its metabolites could have a significant role in the pathogenesis of hypoxic-ischemic injury of neonatal rat brains.

• Clinical and Experimental Pediatrics
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• v.46 no.4
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• pp.345-350
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• 2003

Purpose : Bacterial meningitis is a serious infection of childhood associated with a significant morbidity and mortality. Repeated cerebrospinal fluid(CSF) examination is a useful prognostic indicator and a delayed sterilization is associated with a higher incidence of neurologic abnormalities. In this study we tried to determine the prognostic value of repeated CSF latex agglutination testing. Methods : We retrospectively evaluated 19 patients admitted to Ewha Womans University Mokdong Hospital for bacterial meningitis from January 1997 to June 2002. Bacterial meningitis was confirmed by a positive CSF culture and a positive CSF latex agglutination test. Repeated CSF examinations were done at three, seven, 14, 21 and 28 days after antibiotics therapy. Neuroradiologic studies were performed. Results : The mean age was $10.6{\pm}12.3months$(range; two to 33 months). The male to female ratio was 2.8 : 1. The causative organisms were Haemophilus influenzae type b 57.9%, Group B Streptococcus 21.1%, Streptococcus pneumoniae 15.7% and Escherichia coli 5.3%. Three days after the initiation of antibiotics therapy, repeated CSF latex agglutination tests persisted as positive in nine (47.4%) out of 19 cases, but all CSF cultures became negative. In those cases with negative latex agglutination tests three days after antibiotics therapy, neuroradiologic findings were completely normal. But, in cases with positive latex agglutination tests three days after antibiotics therapy, neuroradiologic abnormalities such as cerebral infarction, encephalomalasia occurred in 44.4%. Conclusion : Repeated CSF latex agglutination testing was valuable as a prognostic factor in bacterial meningitis. Neuroradiologic abnormalities may occur in cases with delayed clearance of CSF latex agglutination tests more often than in cases with negative latex agglutination tests three days after antibiotics therapy.

• Clinical and Experimental Pediatrics
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• v.46 no.3
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• pp.265-270
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• 2003

Purpose : To characterize the infants under 3 months of age with urinary tract infections(UTIs), and especially patients with bacteremia or meningitis Methods : Hospital records of all the infants under 3 months of age discharged from our hospital for 69 consecutive months with the diagnosis of initial episode of UTI were reviewed. UTI was defined when patients had fever with pyuria, and had urine culture results of ${\geq}10^5$ colony forming units/mL from a bag specimen. Patients with previously known urologic abnormality or immunodeficiency were excluded. Nosocomial infections were also excluded from the study. Results : The male:female ratio was 35 : 6. Of the urine cultures, 40(97.6%) yielded single pathogen, one yielded two pathogens. Escherichia coli was the predominant isolate from the urine. Five patients(12%) also had bacteremia. Pathogens isolated from the blood cultures were E. coli(4) and Enterococcus faecalis(1). No patient had culture-positive meningitis or cerebrospinal fluid pleocytosis. Clinical or laboratory findings between patients with and without bacteremia were not different significantly. The rate of vesicoureteral reflux(VUR) was 44%. The sensitivity of ultrasound for detection of VUR was 38%; specificity was 50%. Conclusion : Clinical and laboratory data were not helpful for identifying patients with bacteremia at the time of presentation. Consequently, blood cultures need to be obtained from all febrile infants under 3 months of age with UTIs. A large-scale study including the indication of lumbar puncture for infants with a febrile UTI and study of evaluation and treatment of infants under 3 months of age with UTIs are required.

• Journal of the Korean Geotechnical Society
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• v.31 no.5
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• pp.5-21
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• 2015

An energy pile is a novel type of ground heat exchangers (GHEX's) which sets up heat exchange pipes inside a pile foundation, and allows to circulate a working fluid through the pipe for exchanging thermal energy with the surrounding ground stratum. Using existing foundation structure, the energy pile can function not only as a structural foundation but also as a GHEX. In this paper, six full-scale energy piles were constructed in a test bed with various configurations of the heat exchange pipe inside large-diameter cast-in-place piles, that is, three parallel U-type heat exchangers (5, 8 and 10 pairs), two coil type heat exchangers (with a 500 mm and 200 mm pitch), and one S-type heat exchanger. During constructing the energy piles, the constructability of each energy pile was evaluated with consideration of the installation time, the number of workers and any difficulty for installing. In order to evaluate the thermal performance of energy piles, the thermal performance tests were carried out by applying intermittent (8 hours operating-16 hours pause) artificial cooling operation to simulate a cooling load for commercial buildings. Through the thermal performance tests, the heat exchange rates of the six energy piles were evaluated in terms of the heat exchange amount normalized with the length of energy pile and/or the length of heat exchange pipe. Finally, the economic feasibility of energy pile was evaluated according to the various types of heat exchange pipe by calculating demanded expenses per 1 W/m based on the thermal performance test results along with the market value of heat exchange pipes and labor cost.

• Korean Journal of Agricultural Science
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• v.31 no.1
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• pp.15-25
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• 2004

In order to determine the effect of fermentation by the mycelia of fungal species, Formitella fraxinea and Sarcodon aspratus, on the in vitro dry matter digestibility and pH of mixtures with sawdust plus 20% wheat bran w/w, on dry matter basis to use as a feedstuff or an additive including fungal mycelium into a feedstuff. The mixtures were unfermented (UF) and fermented by Formitella fraxinea(FF) and Sarcodon aspratus(SA) for two weeks at $29^{\circ}C$ in a incubator. Fungal fermentation products were added to the basal diet to the level of 0, 1, 3 and 5%, w/w of diets each. The in vitro dry matter digestibilities, soluble sugar contents and pH of fermentation fluids were measured at 24, 48 and 72hr after fermentation begin. Neutral detergent fiber(NDF) contents in mixtures were lower for SA and UF(80.4 and 82.2%) than for FF(88.3%) (P<0.05). In vitro DM digestibility for 48h was higer for SA(21.2%) than for UF and FF(17.9 and 12.2%). The in vitro dry matter digestibility for 24hr was higher for diets added with FF 1% as 49.18%, and lower for diet added with FF 5%(43.07%) than basal diet(44.98%)(P<0.05), and tended to be higher for the diets added with fungal products. The pH of in vitro fermentation fluids for 24 and 48 hrs fermentation were lower for diets added with all FF and SA than for UF(P<0.05). However, those for 72 hrs fermentation were higher for SA 1%(6.74) than other diets(P<0.05). The soluble sugar concentration of in vitro fermentation fluid was not different between diets for 24 hr fermentation. However, those were higher for all additive diets than basal diet for 48 and 72 hrs fermentation(P<0.05). It could be concluded that dairy cow's diets added with fungal fermentation products have positive effects, and expected it will be more beneficial if more fungal mycelium was contained.

• Geophysics and Geophysical Exploration
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• v.7 no.3
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• pp.164-173
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• 2004

To delineate geothermal water movement at the Pohang geothermal development site, Self-Potential (SP) survey and monitoring were carried out during pumping tests. Before drilling, background SP data have been gathered to figure out overall potential distribution of the site. The pumping test was performed in two separate periods: 24 hours in December 2003 and 72 hours in March 2004. SP monitoring started several days before the pumping tests with a 128-channel automatic recording system. The background SP survey showed a clear positive anomaly at the northern part of the boreholes, which may be interpreted as an up-flow Bone of the deep geothermal water due to electrokinetic potential generated by hydrothermal circulation. The first and second SP monitoring during the pumping tests performed to figure out the fluid flow in the geothermal reservoir but it was not easy to see clear variations of SP due to pumping and pumping stop. Since the area is covered by some 360 m-thick tertiary sediments with very low electrical resistivity (less than 10 ohm-m), the electrokinetic potential due to deep groundwater flow resulted in being seriously attenuated on the surface. However, when we compared the variation of SP with that of groundwater level and temperature of pumping water, we could identify some areas responsible to the pumping. Dominant SP changes are observed in the south-west part of the boreholes during both the preliminary and long-term pumping periods, where 3-D magnetotelluric survey showed low-resistivity anomaly at the depth of $600m\~1,000m$. Overall analysis suggests that there exist hydraulic connection through the southwestern part to the pumping well.