• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.1
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• pp.62-66
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• 2013

Purpose: I-131 is a radioisotope widely used for thyroid gland treatments. The physical half life is 8.01 and characterized by emitting beta and gamma rays which is used in clinical practice for the purpose of acquiring treatment and images. In order to reduce the recurrence rate after surgery in high-risk thyroid cancer patients, the remaining thyroid tissue is either removed or the I-131 is used for treatment during relapse. In cases of using a high dosage of radioactive iodine requiring hospitalization, the patient is administered dosage in the hospital isolation ward over a certain period of time preventing I-131 exposure to others. By checking the radiation amount emitted from patients before discharge, the patients are discharged after checking whether they meet the legal standards (50 uSv/h). After patients are discharged from the hospital, the contamination level is checked in many parts of the ward before the next patients are hospitalized and when necessary, decontamination operations are performed. It is expected that there is exposure to radiation when measuring the ward contamination level and dose check emitted from patients at the time of discharge whereby the radiation exposure by health workers that come from the patients in this process is the main factor. This study analyzed the correlation between discharge dose of patients and ward contamination level through a variety of factors such as renal functions, gender, age, dosage, etc.). Materials and Method: The study was conducted on 151 patients who received high-dosage radioactive iodine treatment at Soon Chun Hyang University Hospital during the period between 8/1/2011~5/31/2012 (Male: Female: 31:120, $47.5{\pm}11.9$, average dosage of $138{\pm}22.4$ mCi). As various factors expected to influence the patient discharge dose & ward contamination such as the beds, floors, bathroom floors, and washbasins, the patient renal function (GFR), age, gender, dosage, and the correlation between the expected Tg & Tg-Tb expected to reflect the remaining tissue in patients were analyzed. Results: In terms of the discharge dose and GFR, a low correlation was shown in the patient discharge dose as the GFR was higher (p < 0.0001). When comparing the group with a dosage of over 150mCi and the group with a lower dosage, the lower dosage group showed a significantly lower discharge dose ($24{\pm}10.4uSv/h$ vs $28.7{\pm}11.8uSv/h$, p<0.05). Age, gender, Tg, Tg-Tb did not show a significant relationship with discharge dose (p> 0.05). The contamination level in each spot of the treatment ward showed no significant relationship with GFR, Tg, Tg-Tb, age, gender, and dosage (p>0.05 ). Conclusion: This study says that discharge of the dose in the patient's body is low in GFR higher and Dosage 150mCi under lower. There was no case of contamination of the treatment ward, depending on the dose and renal association. This suggests that patients' lifestyles or be affected by a variety of other factors.

• Food Science of Animal Resources
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• v.28 no.3
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• pp.283-288
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• 2008

Eight subprimal cuts purchased from the branded Hanwoo beef of 3 quality grades ($1^{++}$, $1^+$, 1) at 13 stores were evaluated the tenderness using Warner-Bratzler shear (WBS). The beef frequency ratio (%) depending on postmortem aging periods were investigated. The 37.5 (quality grade $1^{++}$), 45.8 (quality grade $1^+$), and 36.4% (quality grade $1^{++}$) of branded beef were aged for < 7 d, 26.6 (quality grade $1^{++}$), 47.2 (quality grade $1^+$) and 36.4% (quality grade 1) were aged for $7{\sim}13$ d, and 31.3 (quality grade $1^+$), 4.2 (quality grade $1^+$) and 25.8% (quality grade $1^+$) were aged for 14 to 20 d. The temperature of cold room in stores was ranged average 2.27 to $2.42^{\circ}C$. WBS values for ansimsal (tenderloin), witdngsimsal (ribeye), cheggtsal (shortloin), doganisal (knuckle) and moongchisatae (hind shank) from branded Hanwoo beef of quality grade $1^{++}$ were tender than those from branded Hanwoo beef of quality grade 1 (p<0.05). WBS values for ansimsal (tenderloin) were 2.56 (quality grade $1^{++}$), 2.76 (quality grade $1^+$) and 3.10 kg (quality grade 1), respectively, and those for doganisal (knuckle, quality grade $1^{++}$), hongdukesal (eye of round, quality grade $1^+$) and bosupsal (top sirloin, quality grade 1) were 4.76, 4.96 and 5.66kg, respectively (p<0.05). The frequency ratio (%) of WBS < 3.9 kg in the all subprimal cuts from branded Hanwoo beef of quality grade $1^{++}$ were 100 [ansimsal (tenderloin) and cheggtsal (shortloin)], 87.5 [witdngsimsal (ribeye)] and 62.5% [bosupsal (top sirloin)], whereas that of WBS > 4.6 kg were 50.0% [hongdukesal (eye of round) and doganisal (knuckle)]. The frequency ratio of WBS < 3.9 kg in the an subprimal cuts of quality grade $1^+$ were 100 [ansimsal (tenderloin) and witdngsimsal (ribeye)] and 44.4% [cheggtsal (shortloin) and gurisal (chuck tender)], whereas that of WBS > 4.6 kg were 66.7 [hongdukesal (eye of round)], 55.6 [doganisal (knuckle)] and 44.4% [bosupsal (top sirloin)]. The frequency ratio (%) of WBS < 3.9 kg in the all subprimal cuts of quality grade 1 were 88.9 [ansimsal (tenderloin)], 62.5 [cheggtsal (shortloin)] and 44.4% [witdngsimsal (ribeye)], whereas that of WBS > 4.6 kg were 100.0 [doganisal (knuckle)] 62.7 [hongdukesal (eye of round)], 62.5 [gurisal (chuck tender)] and 55.6% [moongchisatae (hind shank)]. From these results, subprimal cuts from branded Hanwoo beef were marketed with short aging periods and high frequency ratio (%) of WBS > 4.6 kg.

• Clinical and Experimental Reproductive Medicine
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• v.36 no.2
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• pp.111-119
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• 2009

Objective: The aim of this study was to compare the clinical efficacy of clomiphene citrate (CC) and letrozole combined with gonadotropins for controlled ovarian stimulation (COS) in patients with CC-induced thin endometrium Methods: Fifty-one intrauterine insemination cycles performed in patients who previously had a thin endometrium (<8 mm) to ovulation induction using CC were included in this study. A CC 100 mg/day (CC+gonadotropin group, n=26) or letrozole 2.5 or 5 mg/day (letrozole+gonadotropin group, n=25) was administered on day 3~7 of the menstrual cycle, combined with gonadotropins at dose 75~150 IU every other day starting on day 5~7. We compared total dose of gonadotropin used, endometrial thickness, endometrial pattern, number of follicles ${\geq}14\;mm$ on hCG day, pregnancy rate and multiple pregnancy rate between the two groups, which were statistically analyzed using Mann-Whitney U test or Fisher's exact test, where appropriate. Results: There were no significant differences in clinical characteristics such as age, duration of infertility, number of previous IUI cycles, basal serum hormone levels and cause of infertility between the two groups. In both groups, the endometrium was significantly thicker than that of previous ovulation induction cycles using CC. No significant differences were found in the total dose of gonadotropin used, day of hCG administration, the rate of triple endometrium and pregnancy rate. The number of follicles ${\geq}14\;mm$ was significantly lower ($3.7{\pm}1.7$ vs. $2.8{\pm}1.7$, p=0.03) and the endometrium on hCG day was significantly thicker ($7.7{\pm}1.5$ vs. $9.1{\pm}1.7$, p=0.001) in letrozole+gonadotropin group compared to CC+gonadotropin group. Conclusion: The clomiphene citrate and letrozole combined with gonadotropins appear to avoid the undesirable effects on the endometrium frequently seen with CC for ovulation induction. However, in terms of adequate endometrial development or optimal follicular growth, letrozole may be more beneficial than CC for gonadotropin-combined COS in patients with CC-induced thin endometrium. Further prospective randomized controlled studies in a larger scale will be necessary to confirm our findings.

• Journal of agricultural medicine and community health
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• v.30 no.3
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• pp.263-277
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• 2005

Objectives: This study aimed to reveal the oral health conditions based on the dental health behaviors of a community-dwelling elderly. Methods: The subjects included 206 rural dwellers(100 men & 106 women) aged over 65 years old, who received dental health check-ups in the local public health center and its branches attached to 6 respective Myons of Chunchongnamdo Province, during the 2-month period from Jan. 1st to Feb. 28th, 2005. They were examined by dentists and given self-administered questionnaires asking about their dental heaith behaviors and subjective symptoms of gingival bleeding. Results: The oral health conditions based on dental health behavior showed that those who have not taken dental health service a year were found to have significantly greater number of missing teeth(p=0.002), DMFT(p=0.002) and CPITN(p=0.018), and those who have not observed intra-oral conditions a week to have significantly less number of filled teeth(p=0.002) and significantly greater number of missing teeth(p=0.000) and CPITN (p=0.000) than their respective counterparts. In terms of brushing, those who brushed their teeth below "3 times/day" were found to have significantly greater number of decayed teeth(p=0.000), missing teeth(p=0.000), DMFT(p=0.000) and CPITN(p=0.000) than their counterparts. In terms of time spent in brushing, those who spends "below 3 minutes" had significantly greater number of missing teeth(p=0.002) and DMFT(p=0.041), and significantly less number of filled teeth(p=0.036). According to the use of aid tools for cleaning teeth, the group who don't use them had significantly greater number of DMFT(p=0.041) and CPITN(p=0.018) than its counterpart. Classified by smoking habits, smoking groups had significantly greater number of decayed teeth(p=0.035) and CPITN(p=0.001) than non-smoking groups. Multiple regression analysis of the study data revealed that the significant factors influencing number of decayed teeth were number of brushing, sex and intra-oral observation (explanatory power of 14.2%). The significant factors for number of filled teeth were sex, intra-oral observation, use of aid tools, frequency of brushing, subjective health conditions and drinking of sweet beverages(explanatory power of 18.2%), those for number of missing teeth, number of brushing and age(explanatory power of 13.9%) those for DMFT, number of brushing, sex, use of dental service, age(explanatory power: 13.5%), and those for CPITN included smoking habits, use of dental service, use of aid tools (explanatory power: 10.8%). Conclusions: The study results revealed that the dental health behavior of the elderly population is in poor conditions and their consequent intra-oral health conditions are not good. To improve their oral conditions, public campaign and education will be needed to modify unhealthy dental health behaviors.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.1
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• pp.133-137
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• 2010

Purpose: The main function of vitamin D is the mineralization of the brain by increase of calcium and phosphorus, in case it is insufficient in children, lime deposition on cartilage cannot occur so it leads to rachitis, and in adults, it leads to osteomalacia or osteoporosis. It is also strongly believed in the academic world that vitamin D can restrict the growth of cancer cells and prevent heart diseases, which is also somewhat proven in epidemiological researches. While the right density of vitamin D is still being studied, 20-32 ng/mL is believed to be the most ideal density. Therefore, I wanted analyze how much density of 25-Hydroxyvitamin D3 that Koreans possess. Materials and Methods: From February 20th, 2008 to April 21st, 2009, the collection of 2800 serums, from medical examination treated subjects by Neodin Medical Institute, have been tested. The targets were tested by 25-Hydroxyvitamin D (125I Kit: Diasorin, USA), and were analyzed by dividing into many different categories (gender, age, season, region). Results: The average density of male were 20 ng/mL, female 17.08 ng/mL. Per age groups, the density of males were as follows: 10~20-18 ng/mL, 21~30-17 ng/mL, 31~40-19 ng/mL, 41~50-21 ng/mL, 51~60-22 ng/mL, 61~70-22 ng/mL, 71~80-22 ng/mL and 81~90-19.9 ng/mL. Average density of females per age groups, were as follows: 10~20-16 ng/mL, 20~30-15.26 ng/mL, 30~40-16 ng/mL, 40~50-17 ng/mL, 50~60-19 ng/mL, 60~70-19 ng/mL, 70~80-19 ng/mL, and 80~90-17 ng/mL. Per seasons, From December to May, the subjects showed the density of 15.97 ng/mL, while from June to November, it showed 21.60 ng/mL. On density of males from January to April regionally, Seoul+Gyeonggi-Do-15.52 ng/mL, Gangwon-Do-15.33 ng/mL, Choongchung-Do-18.03 ng/mL, Jeonla-Do-18.68 ng/mL, Gyungsang-Do-18.76 ng/mL and Cheju Do-21.23 ng/mL. Conclusions: The vitamin D of Koreans is has been insufficient compared to the suggested amount. Ultraviolet rays, which is the main source of vitamin D is critical, therefore it is suggested that more outdoor activities can definitely help.

• Radiation Oncology Journal
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• v.19 no.4
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• pp.327-334
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• 2001

Purpose : To find out the role of postoperative adjuvant radiotherapy in the treatment of rectal cancer by comparing survival, pelvic control, complication rate, and any prognostic factor between surgery alone and postoperative radiotherapy group. Materials and methods : From Feb. 1982 to Dec. 1996 total 212 patients were treated by radical surgery with or without postoperative radiotherapy due to rectal carcinoma of modified Astler-Coiler stage $B2\~C3$. Of them, 18 patients had incomplete radiotherapy and so the remaining 194 patients were the database analyzed in this study. One hundred four patients received postoperative radiotherapy and the other 90 patients had surgery only. Radiotherapy was peformed in the range of $39.6\~55.8\;Gy$ (mean: 49.9 Gy) to the whole pelvis and if necessary, tumor bed was boosted by $5.4\~10\;Gy$. Both survival and pelvic control rates were calculated by Kaplan-Meier method and their statistical significance was tested by Log-rank test. Multivariate analysis was peformed by Cox proportional hazards model. Results : 5-year actuarial survival rate (5YSR) and 5-year disease-free survival rate (5YDFSR) of entire patients were $53\%\;and\;49\%$, respectively. 5YSRs of surgery alone group and adjuvant radiotherapy group were $63\%\;vs\;45\%$, respectively (p=0.03). This difference is thought to reflect uneven distribution of stages between two treatment groups (p<0.05 by $\chi^2-test$) with more advanced disease patients in adjuvant radiotherapy group. 5YSRs of surgery alone vs adjuvant radiotherapy group in MAC B2+3, C1, C2+3 were $68\%\;vs\;55\%$ (p=0.09), $100\%\;vs\;100\%$, $40\%\;vs\;33\%$ (p=0.71), respectively. 5YDFSRs of surgery alone vs adjuvant radiotherapy group in above three stages were $65\%\;vs\;49\%$ (p=0.14), $100\%\;vs\;100\%$, $33\%\;vs\;31\%$ (p=0.46), respectively. 5-year pelvic control rate (5YPCR) of entire patients was $72.5\%$. 5YPCRs of surgery alone and adjuvant radiotherapy group were $71\%\;vs\;74\%$, respectively (p=0.41). 5YPCRs of surgery alone vs adjuvant radiotherapy group in B2+3, C1, C2+3 were $79\%\;vs\;75\%$ (p=0.88), $100\%\;vs\;100\%$, $44\%\;vs\;68\%$ (p=0.01), respectively. Multivariate analysis showed that only stage was significant factor affecting overall and disease-free survival in entire patients and also in both treatment groups. In view of pelvic control, stage and operation type were significant in entire patients and only stage in surgery alone group but in adjuvant radiotherapy group, operation type instead of stage was the only significant factor in multivariate analysis as a negative prognostic factor in abdominoperineal resection cases. Conclusion : Our retrospective study showed that postoperative adjuvant radiotherapy could improve the pelvic control in MAC C2+3 group. To improve both pelvic control and survival in all patients with MAC B2 or more, other treatment modality such as concurrent continuous infusion of 5-FU, which is the most standard agent, with radiotherapy should be considered.

• Radiation Oncology Journal
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• v.28 no.3
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• pp.155-165
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• 2010

Purpose: In order to evaluate the positional uncertainty of internal organs during radiation therapy for treatment of liver cancer, we measured differences in inter- and intra-fractional variation of the tumor position and tidal amplitude using 4-dimentional computed radiograph (DCT) images and gated orthogonal setup kilovolt (KV) images taken on every treatment using the on board imaging (OBI) and real time position management (RPM) system. Materials and Methods: Twenty consecutive patients who underwent 3-dimensional (3D) conformal radiation therapy for treatment of liver cancer participated in this study. All patients received a 4DCT simulation with an RT16 scanner and an RPM system. Lipiodol, which was updated near the target volume after transarterial chemoembolization or diaphragm was chosen as a surrogate for the evaluation of the position difference of internal organs. Two reference orthogonal (anterior and lateral) digital reconstructed radiograph (DRR) images were generated using CT image sets of 0% and 50% into the respiratory phases. The maximum tidal amplitude of the surrogate was measured from 3D conformal treatment planning. After setting the patient up with laser markings on the skin, orthogonal gated setup images at 50% into the respiratory phase were acquired at each treatment session with OBI and registered on reference DRR images by setting each beam center. Online inter-fractional variation was determined with the surrogate. After adjusting the patient setup error, orthogonal setup images at 0% and 50% into the respiratory phases were obtained and tidal amplitude of the surrogate was measured. Measured tidal amplitude was compared with data from 4DCT. For evaluation of intra-fractional variation, an orthogonal gated setup image at 50% into the respiratory phase was promptly acquired after treatment and compared with the same image taken just before treatment. In addition, a statistical analysis for the quantitative evaluation was performed. Results: Medians of inter-fractional variation for twenty patients were 0.00 cm (range, -0.50 to 0.90 cm), 0.00 cm (range, -2.40 to 1.60 cm), and 0.00 cm (range, -1.10 to 0.50 cm) in the X (transaxial), Y (superior-inferior), and Z (anterior-posterior) directions, respectively. Significant inter-fractional variations over 0.5 cm were observed in four patients. Min addition, the median tidal amplitude differences between 4DCTs and the gated orthogonal setup images were -0.05 cm (range, -0.83 to 0.60 cm), -0.15 cm (range, -2.58 to 1.18 cm), and -0.02 cm (range, -1.37 to 0.59 cm) in the X, Y, and Z directions, respectively. Large differences of over 1 cm were detected in 3 patients in the Y direction, while differences of more than 0.5 but less than 1 cm were observed in 5 patients in Y and Z directions. Median intra-fractional variation was 0.00 cm (range, -0.30 to 0.40 cm), -0.03 cm (range, -1.14 to 0.50 cm), 0.05 cm (range, -0.30 to 0.50 cm) in the X, Y, and Z directions, respectively. Significant intra-fractional variation of over 1 cm was observed in 2 patients in Y direction. Conclusion: Gated setup images provided a clear image quality for the detection of organ motion without a motion artifact. Significant intra- and inter-fractional variation and tidal amplitude differences between 4DCT and gated setup images were detected in some patients during the radiation treatment period, and therefore, should be considered when setting up the target margin. Monitoring of positional uncertainty and its adaptive feedback system can enhance the accuracy of treatments.

• KDI Journal of Economic Policy
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• v.13 no.4
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• pp.91-116
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• 1991

Market liberalization progressing simultaneously with high and rapidly rising domestic wages has created an adverse business environment for domestic firms. Korean firms are losing their international competitiveness in comparison to firms from LDC(Less Developed Countries) in low-tech industries. In high-tech industries, domestic firms without government protection (which is impossible due to the liberalization policy and the current international status of the Korean economy) are in a disadvantaged position relative to firms from advanced countries. This paper examines the division of roles between the private sector and the government in order to achieve a successful structural adjustment, which has become the impending industrial policy issue caused by high domestic wages, on the one hand, and the opening of domestic markets, on the other. The micro foundation of the economy-wide structural adjustment is actually the restructuring of business portfolios at the firm level. The firm-level business restructuring means that firms in low-value-added businesses or with declining market niches establish new major businesses in higher value-added segments or growing market niches. The adjustment of the business structure at the firm level can only be accomplished by accumulating firm-specific managerial assets necessary to establish a new business structure. This can be done through learning-by-doing in the whole system of management, including research and development, manufacturing, and marketing. Therefore, the voluntary cooperation among the people in the company is essential for making the cost of the learning process lower than that at the competing companies. Hence, firms that attempt to restructure their major businesses need to induce corporate-wide participation through innovations in organization and management, encourage innovative corporate culture, and maintain cooperative labor unions. Policy discussions on structural adjustments usually regard firms as a black box behind a few macro variables. But in reality, firm activities are not flows of materials but relationships among human resources. The growth potential of companies are embodied in the human resources of the firm; the balance of interest among stockholders, managers, and workers of the company' brings the accumulation of the company's core competencies. Therefore, policymakers and economists shoud change their old concept of the firm as a technological black box which produces a marketable commodities. Firms should be regarded as coalitions of interest groups such as stockholders, managers, and workers. Consequently the discussion on the structural adjustment both at the macroeconomic level and the firm level should be based on this new paradigm of understanding firms. The government's role in reducing the cost of structural adjustment and supporting should the creation of new industries emphasize the following: First, government must promote the competition in domestic markets by revising laws related to antitrust policy, bankruptcy, and the promotion of small and medium-sized companies. General consensus on the limitations of government intervention and the merit of deregulation should be sought among policymakers and people in the business world. In the age of internationalization, nation-specific competitive advantages cannot be exclusively in favor of domestic firms. The international competitiveness of a domestic firm derives from the firm-specific core competencies which can be accumulated by internal investment and organization of the firm. Second, government must build up a solid infrastructure of production factors including capital, technology, manpower, and information. Structural adjustment often entails bankruptcies and partial waste of resources. However, it is desirable for the government not to try to sustain marginal businesses, but to support the diversification or restructuring of businesses by assisting in factor creation. Institutional support for venture businesses needs to be improved, especially in the financing system since many investment projects in venture businesses are highly risky, even though they are very promising. The proportion of low-value added production processes and declining industries should be reduced by promoting foreign direct investment and factory automation. Moreover, one cannot over-emphasize the importance of future-oriented labor policies to be based on the new paradigm of understanding firm activities. The old laws and instititutions related to labor unions need to be reformed. Third, government must improve the regimes related to money, banking, and the tax system to change business practices dependent on government protection or undesirable in view of the evolution of the Korean economy as a whole. To prevent rational business decisions from contradicting to the interest of the economy as a whole, government should influence the business environment, not the business itself.

• Journal of Yeungnam Medical Science
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• v.8 no.2
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• pp.185-201
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• 1991

A household survey was conducted to compare the patterns of morbidity and medical care utilization between medical aid beneficiaries and medical insurance beneficiaries. The study population included 285 medical aid beneficiaries that were completely surveyed and 386 medical insurance benficiaries selected by simple random sampling from a Dong(Township) in Taegu. Well-trained surveyers mainly interviewed housewives with a structured questionnaire. The morbidity rates of acute illness during the 15-day period, were 63 per 1,000 medical aid beneficiaries and 62 per 1,000 medical insurance beneficiaries. The rates for chronic illness were 123 per 1,000 medical aid beneficiaries and 73 per 1,000 medical insurance beneficiaries. The most common type of acute illness in medical aid and medical insurance beneficiaries was respiratory disease. In medical aid beneficiaries, musculoskeletal disease was most common, but in medical insurance beneficiaries, gastrointestinal disease was most common. The mean duration of acute illness of medical aid beneficiaries was 3.8 days and that of medical insurance beneficiaries was 6.8 days. During the one year period, mean duration of medical aid beneficiaries chronic illnesses was 11.5 months which was almost twice as long compared to medical insurance beneficiaries. Pharmacy was most preferrable facility among the acute illness patient in medical aid beneficiaries, but acute cases of medical insurance beneficiaries visited the clinic most commonly. Chronic cases of both groups visited the clinic most frequently. There were some findings suggesting that much unmet need existed among the medical aid beneficiaries. In acute cases, the average number of days of medical aid users utilized medical facilities was less than medical insurance users. On the other hand, the length of medical care utilization of chronic cases was reversed. Geographical accessibility was the most important factors in utilization of medical facilities. Almost half of the study population answered the questions about source of funds on medical security correctly. Most respondents considered that the objective of medical security was afford ability. The chief complaint on hospital utilization was the complicated administrative procedures. These findings suggest that there were some problems in the medical aid system, especially in the referral system.

• Neonatal Medicine
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• v.18 no.1
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• pp.82-88
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• 2011

Purpose: This study aims to describe the clinical characteristics of adrenal insufficiency-associated hypotension in preterm infants and the effects of hydrocortisone therapy on their cardiovascular system and serum electrolytes. Methods: Twelve preterm infants less than 32 gestational weeks admitted to neonatal intensive care unit (NICU) of the Seoul National University Bundang Hospital from January 2007 to August 2009 with clinical and laboratory findings suggestive of adrenal insufficiency were analyzed retrospectively. Results: Gestational age was 27.8${\pm}$2.5 weeks and birth weight was 1,110${\pm}$307 g. Postnatal age, postmenstrual age, weight at the onset of adrenal insufficiency-associated hypotension were 19${\pm}$7 day, 30.6${\pm}$2.4 weeks, 1,285${\pm}$365 g. In preterm infants who showed vasopressor resistance, intravenous hydrocortisone was started with a stress dose of 4 mg/kg/day, maintained for 2.2${\pm}$0.7 days, and then tapered. Serum cortisol concentration before hydrocortisone administration was 11.6${\pm}$4.1 mg/dL. Mean blood pressure increased from 25.0${\pm}$5.4 mmHg to 35.0${\pm}$5.3 mmHg, 38.3${\pm}$8.0 mmHg and 41.9${\pm}$6.5 mmHg at time of hydrocortisone administration and 2, 4 and 6 hours after hydrocortisone administration. Urine output increased from 0.9${\pm}$0.6 mL/kg/hr to 4.1${\pm}$3.4 mL/kg/hr. Twelve hours after the administration of hydrocortisone, dopamine requirement decreased from 11.0${\pm}$2.9 $\mu$g/kg/min to 8.0${\pm}$2.3 $\mu$g/kg/min, and to 5.5${\pm}$3.4 ${\mu}g$/kg/min after 24 hours. Serum sodium concentration was increased from 130${\pm}$4 mEq/L to 136${\pm}$4 mEq/L, serum potassium concentration was decreased from 6.1${\pm}$1.1 mEq/L to 4.6${\pm}$0.6 mEq/L before and 12 hours after hydrocortisone administration. Conclusion: In preterm infants with adrenal insufficiency-associated hypotension, hydrocortisone administration improved blood pressure and urine output, decreased vasopressor requirement, and normalized serum electrolyte abnormalities.