• Toxicological Research
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• v.23 no.2
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• pp.151-158
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• 2007

tert-Butyl acetate is an organic solvent used for coatings, industrial cleaning, and surface treatment applications. This study investigated the potential adverse effects of tert-butyl acetate on pregnant dams and embryo-fetal development after maternal exposure on gestational days 6 through 19 in rats. The test chemical was administered to pregnant rats by gavage at dose levels of 0, 500, 1,000, 1,500, and 2,000 mg/kg/day. All dams were subjected to a caesarean section on day 20 of gestation and their fetuses were examined for any external, visceral, and skeletal abnormalities. At 2,000 mg/kg, treatment-related clinical signs, including piloerection, abnormal gait, decreased locomotor activity, loss of fur, reddish tear, anorexia, nasal discharge, vocalization and coma, were observed in a dose-dependent manner. All dams died between the 2nd day and 5th day of treatment due to a severe systemic toxicity. At 1,500 mg/kg, minimal maternal toxicity including an increase in the incidence of decreased locomotor activity and loss of fur, and an increase in the weights of adrenal glands and liver was observed. On the contrary, no significant adverse effect on the embryo-fetal development was detected. There were no adverse effects on either pregnant dams or embryo-fetal development at <1,000 mg/kg. These results show that a 14-day repeated oral dose of tert-butyl acetate in rats caused a minimal maternal toxicity including increases in the incidence of clinical signs and the weights of adrenal glands and liver, but no embryotoxicity and teratogenicity at 1,500 mg/kg/day. Under these experimental conditions, the no-observed-adverse-effect level (NOAEL) of tert-butyl acetate is estimated to be 1,000 mg/kg per day for dams and 1,500 mg/kg per day for embryo-fetal development.

• Journal of the Korean Society of Radiology
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• v.81 no.2
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• pp.310-323
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• 2020

To treat congenital heart disease, it is important to understand the anatomical structure correctly. Three-dimensional (3D) printed models of the heart effectively demonstrate the structural features of congenital heart disease. Occasionally, the exact characteristics of complex cardiac malformations are difficult to identify on conventional computed tomography, magnetic resonance imaging, and echocardiography, and the use of 3D printed models can help overcome their limitations. Recently, 3D printed models have been used for congenital heart disease education, preoperative simulation, and decision-making processes. In addition, we will pave the way for the development of this technology in the future and discuss various aspects of its use, such as the development of surgical techniques and training of cardiac surgeons.

• Journal of Bio-Environment Control
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• v.15 no.3
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• pp.250-256
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• 2006

This experiment was conducted to investigate the hydroponic culture possibility and the optimal solution strength of 'Pechika' ever-bearing strawberry in summer highland. Maximum room temperature and minimum root zone temperature of plastic house were $30.8^{\circ}C\;and\;19^{\circ}C$ in highland respectively and $4^{\circ}C\;and\;3^{\circ}C$ lower than in level and. The growth of 'Pechika' was better in highland. There was effective in producing the good yield and fruit quality in highland and the deformed fruits also were decreased. The soluble solid and titratable acidity content increased in highland. Early growth was the most effective in standard solution $(EC\;0.75dS\;m^{-1})$ and had a tendency to be inhibition with increasing nutrient concentration. Standard solution was also the highest to yield about 2,064kg/10a among treatments, and 2/3S, 4/3S, 5/3S by turns. The browning roots and root activity increased when the solution strength was increased, especially in EC $1.25dS{\cdot}m^{-1}$. The soluble solids and acidity content of fruits were increased with higher solution strength. Therefor, the summer hydroponic culture of 'Pechika' ever-bearing strawberry was suitable in highland and effective in standard solution $(EC\;0.75dS{\cdot}m^{-1})$ in solution control.

• Korean Journal of Agricultural and Forest Meteorology
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• v.26 no.2
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• pp.103-113
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• 2024

The effect of harvesting time on the growth, marketable tuber yield, and tuber quality of spring potato (Solanum tuberosum L. cv. Dami) were analyzed in the southern paddy fields in order to determine the optimal harvesting time. At 30-50 days after flowering, the total and marketable tuber yields of spring potato reached their maxima and commercial tuber rate was also high. External defects such as tuber malformation or crack did not occur until 40 days after flowering, but after that, secondary growth such as shooting appeared. Among the nutrient compositions of tubers, carbohydrate content accounted for more than 60% of tuber dry weight without significant difference among harvesting times until 50 days after flowering. The crude protein content decreased slightly as the harvesting time was delayed. However, the mineral nutrient content of tubers decreased with delaying harvesting time and was lowest at 30-40 days after flowering. Therefore, the optimal harvesting time of spring potato was judged to be 30-40 days after flowering, when marketable tuber size and quality were great as less affected by high temperature or waterlogging under natural environmental conditions.

• Journal of Food Hygiene and Safety
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• v.13 no.2
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• pp.121-128
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• 1998

Ochratoxin A (OA) is a mycotoxin produced by Aspergillus ochraceus as well as other molds. It is a natural contaminant of mouldy food and feed. OA has a number of toxic effects, the most prominant being nephrotoxicity. Futhermore, OA is immunosuppressive, genotoxic, teratogenic and carcinogenic. OA inhibits protein synthesis by competition with phenylalanine in the phenylalanine-tRNA aminoacylation reaction. Recently, lipid peroxidation induced by OA has been reported, indicating that the lesion induced by this mycotoxin could be also related to oxidative pathway. Since it seems impossible to avoid contamination of foodstuffs by toxigenic fungi, detoxification and detoxication of OA are needed. In this study we investigated the protective effects of aspartame (Asp), phenylalanine (Phe), polyphenol 70S (PP) and aloe extract (AE) on the nephrotoxicity induced by subacute exposure to the OA. Asp and Phe are structural analogues of OA. PP, an ingredient of Green Tea and AE have been known as antioxidant and radical scavenger. Phe (40 mg/kg, i.p.) and Asp (25 mg/kg, p.o.) were administered to Sprague-Dawley rats simultaneously with OA (2.0 mg/kg, p.o.) for 2 weeks. PP (200 mg/kg, p.o.) and AE (50 mg/kg, i.v.) were pretreated before administration of OA, for 2 weeks and 3 days, respectively. Using enzymuria, BUN level, creatinemia and histophathologic examination as indices of renal damage, we observed that all of four compounds prevented the nephrotoxic effects induced by OA. It seems that structural analogues of OA such as Asp and Phe have better protective effect on the nephrotoxicity of OA than antioxidants. These results indicate that 1) formation of free radical and lipid peroxidation are likely to be involved in the nephrotoxicity of OA in vivo, 2) Asp, PP and AE might be used for prevention of renal lesions in cases of ochratoxicosis.

• Radiation Oncology Journal
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• v.6 no.2
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• pp.269-276
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• 1988

Eight patients with intracranial tumors or arteriovenous malformation (AVM)s which were less than 3 cm in diameter were treated by a technique of stereotactic radiotherapy during the 4months period from July 1988 through October 1988 at the Division of Radiation Therapy, Kang-Nam St. Mary's Hospital, Catholic University Medical College. The patients were diagnosed as AVMs in 3 cases, acoustic neurinoma, craniopharyngiom (recurrent), hemangioblastoma, pineocytoma, and pituitary microadenoma in each case. There are several important factors in this procedure, such as localization system, portal, field size, radiation dose, and perioperative supportive care. It is suggested that stereotactic radiotherapy may be peformed safely with a radiation dose of 12-30 Gy. So this nonivasive procedure can be used to treat unresectable intracranial tumors or AVMs. Of these, clinical symptoms had been regressed in AVMs in 2 cases at 3 months and 2 months after Stereotactic radiotherapy, one of whom was confirmed slightly regressed on the follow-up angiogram. And also craniopharyngioma and pineocytoma was minimally regressed on 3 month follow-up CT.

• Tuberculosis and Respiratory Diseases
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• v.65 no.2
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• pp.110-115
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• 2008

Background: Congenital cystic adenomatoid malformation of the lung (CCAM) is a rare congenital developmental anomaly of the lower respiratory tract. Most cases are diagnosed within the first 2 years of life, so adult presentation of CCAM is rare. We describe here six adult cases of CCAM and the patients underwent surgical resection, and all these patients were seen during a five and a half year period. The purpose of this study was to analyze the clinical, radiological and histological characteristics of adult patients with CCAM. Methods: Through medical records analysis, we retrospectively reviewed the clinical characteristics, the chest pictures (X-ray and CT) and the histological characteristics. Results: Four patients were women and the mean age at diagnosis was 23.5 years (range: 18~39 years). The major clinical presentations were lower respiratory tract infection, hemoptysis and pneumothorax. According to the chest CT scan, 5 patients had multiseptated cystic lesions with air fluid levels and one patient had multiple cavitary lesions with air fluid levels, and these lesions were surrounded by poorly defined opacities at the right upper lobe. All the patients were treated with surgical resection. 5 patients underwent open lobectomy and one patient underwent VATS lobectomy. On the pathological examination, 3 were found to be CCAM type I and 3 patients were CCAM type II, according to Stocker's classification. There was no associated malignancy on the histological studies of the surgical specimens. Conclusion: As CCAM can cause various respiratory complications and malignant changes, and the risks associated with surgery are extremely low, those patients who are suspected of having or who are diagnosed with CCAM should go through surgical treatment for making the correct diagnosis and administering appropriate treatment.

• Journal of Chest Surgery
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• v.30 no.12
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• pp.1184-1189
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• 1997

Tetralogy of Falloff is the most common cyanotic congenital cardiac malformation. Between April 1984 and December 1993, we experinced with 39 cases of total correction for the tetralogy of Falloff at the department of Thoracic and Cardiovascular Surgery, Masan Samsung General Hospital. The results were as follows; There were 14 males and 25 females, and their ages ranged from 2 to 36 years, with an average age of 13.33 $\pm$7.40 years. There was type I VSD in 10 cases(25.6%), type II VSD in 19 cases(48.8%) and type 1+ II VSD in 10 cases(25.6%) Types of right ventricular outflow tract obstruction were valvar + infundibular stenosis in 19 cases(48.7%), valvar + infundibular + annular stenosis in 10 cases(25.6%), infundibular stenosis in 9 cases(23.1%)and pure valvar stenosis in 1 case(2.6%). Right ventricular outflow tract patch widening was necessary in 33 cases(84.6%) and a Iransannular patch including 2 cases of Monocusp-bearing outflow patch was used in 10 cases. n 36 hospital survivors, 23 patients were evaluated by 2 dimensional and doppler echocardiography. The most common complication was arrthymia, especially complete right bundle branch block, in 30 cases (76.9%). The operative mortality was 7.7%, and the cause of death was low cardiac output syndrome.

• Journal of the Korean Chemical Society
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• v.35 no.1
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• pp.24-37
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• 1991

We synthesized the binuclear Tetradentate Schiff base nickel(II) and copper(II) complexes ; [Ni(II)$_2$(SMPO)$_2$(L)$_2$], [Ni(II)$_2$(SPPD)$_2$(L)$_2$] and [Cu(II)$_2$(SMPD)$_2$] and [Cu(II)$_2$(SPPD)$_2$] (where, L : Py, DMSO and DMF). We identified the structure of these complexes by elemental analysis, IR-spectrum, T.G.A, D.S.C and ESR measurements. According to the results of cyclic voltammetry and DPP measurements in aprotic solvent included 0.1M TEAP as supporting electrolyte, we knew that diffusional controlled redox process of one step with one electron was irreversible process in 0.1M TEAP-Py solution. Also it was reversible or quasi reversible process in 0.1M TEAP-DMSO solution and reversible or E.C reaction mechanism in 0.1M TEAP-DMF solution at mononuclear complexes ; [Cu(II)(SOPD)] and [Ni(II)(SOPD)(L)$_2$]. But, we knew that diffusional controlled redox process of two step for one electron of binuclear complexes was as follows. The values of redox potential for dimeric complexes in 0.1M TEAP-L solution (where, L ; Py, DMSO and DMF) with scan rate 100mV/sec.

• The Korean Journal of Mycology
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• v.5 no.1
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• pp.13-19
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• 1977

In order to investigate histopathologically the nature of varietal resistance and infection process of the rice bast fungus, Pyricularia oryzae. this experiment was undertaken by using the resistant cultivar Tongil and susceptible cultivars Norin No.6 and Jinheung in 1973 to 1974. 1) It was found that appressorium of the fungus forms not only at 4 hours after incubation under the favorable conditions but also peak of appressorial formation is at 48 hours treatment. Physical stimulus known to be a definite factor for appressorial formation. The optimum temperature range for appressorial infection was at $24^{\circ}C$ to $28^{\circ}C$, and pH was between 4.8 to 8.0 with 6.8 as the optimum. 2) Although percent of appressorial formation on the leaves of resistant Tongil and susceptiible Norin No.6 were only slightly different, there was a remarkable difference between resistant and susceptible cultivars with regard to percent of hyphal infection and index for hyphal extension. Index of hyphal extension was 1.6-2.7 in Tonyil. while in susceptible cultivar was 3.4-6.6. The rate of discoloration of infected cells, a indication of hypersensitivity, was greater in the resistant than in susceptible cultvar. 3) Therefore, it could be concluded that resistance of Tongil cultivar may be attributable to a higher degree of mechanical barriers as well as a higher level of antifungal substance accumulation.