• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.6
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• pp.520-530
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• 2006

Undifferentiated mesencymal stem cells(UMSCs) have been thought to be multipotent cells that can replicate as undifferentiated cells and that have the potential to differentiate into lineages of mesenchymal tissue including the bone, cartilage, fat, tendon, muscle, and marrow stroma. It can be used to sinus lifting, Guided bone regeneration, other bone graft in dental part. The purpose of this study is to evaluate the effect of mesencymal stem cells on sinus augmentation with autogenous bone, fibrin glue mixture in a rabbit model. 8 New Zealand white rabbits were divided randomly into 4 groups based on their time of sacrifice(1, 2, 4 and 8 weeks). First, undifferentiated mesenchymal stem cells were isolated from iliac crest marrow of rabbits and expanded in vitro. cell culture was performed in accordance with the technique described by Tsutsumi et al. In the present study, The animals were sacrificed at 1, 2, 4 and 8 weeks after transplantation, and the bone formation ability of each sides was evaluated clinically, radiologically, histologically and histomorphologically. According to the histological observations, Stem cell group showed integrated graft bone with host bone from sinus wall. At 2 and 4weeks, It showed active newly formed bone and neovascularization. At 8 weeks, lamella bone was observed in sinus graft material area. Radiologically, autobone with stem cell showed more radiopaque than autobone without stemcell. there were significant differences in bone volume between 2 and 4 weeks (p<0.05). In summary, the autobone with stem cells had well-formed, newly formed bone and neovasculization, compared with the autobone without stem cells (esp. 2 weeks and 4 weeks) The findings of this experimental study indicate that the use of a mixture of mesenchymal stem cell yielded good results in osteogenesis and bone volume comparable with that achieved by autogenous bone. Therefore, this application of this promising new sinus floor elevation method for implants with tissue engineering technology deserves further study.

• Journal of agricultural medicine and community health
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• v.7 no.1
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• pp.66-73
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• 1982

Paragonimus westermani is one of the most popular endemic parasitic diseases in Korea. The nation-wide prevalence survey were carried out by Gobayashi (1921) with sputum examination and by Walton and Chyu (1959) with the intradermal skin test respectively. Recent studies showed the decline of positive rate in intradermal skin test of the local inhabitants and also showed the less distribution of intermediate host. The fact seemed that caused by economic improvement of village people, decrease of intermediate host by increasing use of pesticides, becoming lower water level at streams and rivers and better irrigation and finally by better community health education etc. Gangwha area of Gyeonggi-Do was found out as an endemic area of Paragonimus westermani through some studies in the past, however, in the vicinity area of Gangwha, the study in Kyodong island (myon) was carried out in 1965 by Yun et al. Therefore author carried out the intradermal skin test for 2,380 students of primary, middle and high school in Kyodong island and Samsan island. The results showed as follows : 1) The positive rate of intradermal test for paragonimus westermani infection showed positive in 152 among 1,845 students (8.2%) in Kyodong island, and 21 among 637 students (3.3%) in Samsan island respectively. 2) According to grade levels, 49 among 973 students (5.0%) in primary school, 62 among 962 students (6.4%) in middle school and 53 among 445 students (11.9%) in high school showed positive rate. This showed the higher grade the higher positive rate. 3) Among these total 164 positive cases in the intradermal skin test, only in 3 cases eggs were found in sputum. 4) Finding out the intermediate host, only 28 crayfishes from Kyodong island and 12 from Samsan island were collected and examined for metacercaria infection, however, none of metacercaria was found. 5) As a control group, 2 primary schools from the main island were selected. In these schools from the sixth grade students showed positive rate of 4.8% in Naega primary school and 0% in Hajeom Primary school respectively. Those results showed much decrease than studies carried out in the past. 6) The survey for food habit showed that 15 among 1,274 students (1.2%) had experiences of eating raw intermediate host(crayfish) and 266 among 988 students (27.0%) ate cooked.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1545-1552
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• 2005

Sanguisorba officinalis L. has been used as a traditional remedy for arthritis, neuralgia, diarrhea, vomiting, gastric ulcer and gastro-intestinal disorders. This study was performed to investigate the protective effects of ethylacetate fraction of Sanguisorba officinalis L. ethanol extract (SOE) on the gastric mucosal damage and gastric ulcer induced by HCI-ethanol, indomethacin, Shay-ligation method, restraint and water-immersion stress, and cysteamine in rats. The experiment animals were divided into four groups: a negative control group (CON), positive control group (cimetidine 100 mg/kg-CMT or omeprazol 100 mg/kg administrated group-OMT), SOE 200 mg/kg administrated group (SOL) and SOE 400 mg/kg administrated group (SOH), respectively. Rats were given an oral or intraduodenal administration of SOE, and all SOE treatment groups compared with the CON significantly inhibited HCI-ethanol-induced acute gastritis and indomethacin-induced gastric ulcers in dose-dependent manner, of which effects were lower in a positive control drug (CMT). The inhibition rates ($\%$) on the acute gastritis induced by HCI-ethanol and the gastric ulcers induced by indomethacin in rats, 17.66$\%$ and 48.28$\%$ in SOL, 21.71$\%$, and 51.08$\%$ in SOH, and 47.26$\%$ and 58.26$\%$ in CMT compared with CON, respectively, In pylorus ligated rats, the groups of SOE showed decreases in the volume of gastric secretion and acid output. However, no significant differences were observed in the pepsin activity between treated groups . In addition, SOH also depressed gastric ulcers induced by restraint and water-immersion stress and duodenal ulcers induced by cysteamine. These results suggest that Sanguisorba officinalis L. has remarkable antigastric ulcer effects and could be developed as a new antigastric ulcer agents.

• Clinical and Experimental Pediatrics
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• v.52 no.2
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• pp.167-175
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• 2009

Purpose : This study has been conducted to analyze whether the biochemical nutrition indexes might be useful and effective for evaluating the nutrition states of children. Methods : We evaluated 269 children, aged 3-9 years old, who had visited Gangneung Asan Hospital for elective surgery from January 2006 to December 2007, and examined their anthropometric and preoperative laboratory data with retrospective analysis. The children were classified into underweight, normal weight, overweight, and obese groups according to body mass index (BMI). The biochemical nutrition indexes (total lymphocyte count (TLC), hemoglobin, hematocrit, serum albumin, cholesterol, et al) of each group were then analyzed statistically. Results : None of the groups showed statistically significant differences in TLC. Serum albumin decreased significantly in the underweight group. Red blood cell (RBC) count, hemoglobin, hematocrit, and serum total cholesterol in the obese group were higher than in the normal weight group. None of the groups showed statistically significant increase in mean corpuscular volume or mean corpuscular hemoglobin, and it seems that the increase of hemoglobin and RBC count in the overweight and obese groups is due to the enhancement of erythropoiesis rather than iron metabolism. However, in females, almost all nutrition indexes except albumin were statistically significantly poor. Conclusion : Serum albumin, total cholesterol, RBC count, hemoglobin, and hematocrit were useful as nutrition indexes. However, except for albumin, these indexes were significantly poor for females. More control studies are needed to confirm the effectiveness of biochemical indexes for evaluating the nutritional state of children.

• Journal of the Korean Wood Science and Technology
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• v.11 no.3
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• pp.58-69
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• 1983

This research is performed to compare lignin compounds isolated in Pinus koraiensis Sieb et Zucco, with those compounds which have been already isolated. and to elucidate IR spectra of functional groups and aromatic nucleus for chemical structure of lignin. In vanillin and dehydrodivanillin having carbonyl group ill ${\alpha}$-position. characteristic absorption band of carbonyl group was confirmed in 1665 $cm^{-1}$. Absorption band of vanillic and syringic acid with carboxyl group were indicated in 1675 and 1690 $cm^{-1}$ respectively. Syringic acid showed low wave number because this was affected by methoxyl group. Characteristic absorption bands of guaiacyl, syringly and guaiacyl-syringyl co-polymer nucleus were clearly disclosed in diarylpropane compounds. It were reconfirmed that absorption band of guaiacyl showed longer wave number than of syringly nucleus.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.2
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• pp.51-78
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• 2021

Followed by 'start-up', the theme of 'scale-up' has been considered as an important agenda in both corporate and policy spheres. In particular, although it is a term commonly used in industry and policy fields, even a conceptual definition has not been achieved from the academic perspective. "Corporate Growth" in the academic aspect and "Business Growth" in the practical management field have different understandings (Achtenhagen et al., 2010). Previous research on corporate growth has not departed from Penrose(1959)'s "Firm as a bundle of resources" and "the role of managers". Based on the theory and background of economics, existing research has mainly examined factors that contribute to firms' growth and their growth patterns. Comparatively, we lack knowledge on the firms' growth with a focus on 'annual revenue growth rate'. In the early stage of the firms, they tend to exhibit a high growth rate as it started with a lower level of annual revenue. However, when the firms reach annual revenue of more than 100 billion KRW, a threshold to be classified as a 'middle-standing enterprise' by Korean standards, they are unlikely to reach a high level of revenue growth rate. In our study, we used our sample of 333 companies (6.7% out of 5,000 'fastest-growing' companies) which reached 15% of the compound annual growth rate in the last three years with more than USD 100 million. It shows that sustaining 'high-growth' above a certain firm size is difficult. The study focuses on firms with annual revenue of more than $100 billion (approximately 120 billion KRW) from the 'Inc. 2020 fast-growing companies 5,000' list. The companies have been categorized into 1) Fast-growing companies (revenue CAGR 15%~40% between 2016 and 2019), 2) Hyper-growing companies (40%~99.9%), and 3) Super-growing (100% or more) with in-depth analysis of each group's characteristics. Also, the relationship between the revenue growth rate, individual company's strategy choice (market orientation, generic strategy, growth strategy, pioneer strategy), industry/market environment, and firm age is investigated with a quantitative approach. Through conducting the study, it aims to provide a reference to the 'Hyper-Growing Model' that combines the paths and factors of growth strategies. For policymakers, our study intends to provide a reference to which factors or environmental variables should be considered for 'optimal effective combinations' to promote firms' growth.

• Clinical and Experimental Reproductive Medicine
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• v.18 no.2
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• pp.201-208
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• 1991

Recently the application of gonadotropin-releasing hormone (GnRH) agonist to superovulation in previous poor responders has resulted in the improved outcomes after in vitro fertilization (IVF) outcome. However, poor responders with poor estradiol $(E_2)$ rise or single dominant follicle are a particularly challenging group. Recent reports have also shown that patients with higher basal serum follicle stimulating hormone (FSH) level, result in poorer ovarian response and lower pregnancy rate. Analysis of the differences of superovulation outcomes according to the different protocols of GnRH agonist, long (L, n = 18) and short (S, n = 16) protocols, in patients with high basal FSH levels (>20mIU/ml) were undertaken at Seoul National University Hospital from June to October 1990. The administration of GnRH agonist was begun on day 21 of the cycle in long protocol, and on day 2 in short protocol. Ages of patients and husbands, basal FSH and luteinizing hormone (LH) levels and FSH/LH ratio did not differ significantly. Types and causes of infertility were evenly distributed. Whereas the duration of stimulation and the amounts of gonadotropins administered were significantly reduced in short protocol, the numbers of oocytes retrieved and cleaved, the cleavage rate and the number of embryos transferred were higher in long protocol without statistical signifieance. The pregnancy rate per ET was 16.7% (2/12) in short protocol, and 17.6% (3/17) in long protocol. These data suggest that both protocols result in the similar superovulation outcomes in patients with higher basal serum FSH levels.

• Korean Journal of Plant Resources
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• v.31 no.2
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• pp.109-116
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• 2018

Erectile dysfunction (ED), also known as impotence, is the inability to attain and sustain an erection firm enough to have sexual intercourse. Frequent ED may be a symptom of health problems including heart disease, obesity, alcoholism, stress, smoking, and depression, that need treatment. This study aimed to effect of complex extract (CPL) including Cornus officinalis on sexual function factor in the erectile dysfunction rat model. The erectile dysfuction rat model was induced by cimetidine (500 mg/kg in 5% ethanol, oral injection 2 weeks). Rats were oral administered with different concentration of CPL in rat erectile dysfunction model. As a results, sexual function factors (NO, cGMP) significantly improved in CPL treated groups (CPL-300, 600, 900 mg/kg) compared to CON group. Serum testosterone was increased in a dose-dependent manner after CPL treatment. Furthermore, administrations of CPL restored lumen areas of the prostate in the erectile dysfunction rat model. These results indicated that CPL alleviated erectile dysfunction by increasing sexual function factor and testosterone in rat model. CPL could be used to natural treatement for erectile dysfunction. However, further study is required to identify active ingredient and its mechanism of erectile dysfunction.

• Clinical and Experimental Reproductive Medicine
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• v.27 no.1
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• pp.67-74
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• 2000

Objective: This study was conducted to investigate the effect of vitrification on the implantation and the pregnancy of human blastocysts. Method: The transfer of the frozen-thawed blastocysts by the slow freezing or vitrification was performed between January 1998 and July 1999. The zygotes derives from IVF were cocultured with cumulus cells in YS medium containing 20% hFF for 5days. Two or three of the best balstocysts produced on day 5 were transferred into the uterus, and then supernumerary blastocysts were randomly divided into two groups. One was frozen by slow freezing and the other was frozen by vitrification method. The slow freezing procedure was performed in two steps (5% glycerol and 9% glycerol + 0.2 M sucrose for 10 min, respectively) using programmed freezer ($-2^{\circ}C$/min to $-7^{\circ}C$, manual seeding at $-7^{\circ}C$, $-0.3^{\circ}C$/min to $-38^{\circ}C$ and plunged into $LN_{2}$). The blastocysts frozen by slow freezing were thawed at $36^{\circ}C$ then removed glycerol in 7 steps. The vitrification procedure was performed in three steps (10% glycerol for 5 min, 10% glycerol + 20% ethylene glycol for 5 min, 25% glycerol + 25% ethylene glycol and directly $LN_{2}$ within 1 min). The blastocysts frozen by vitrification were thawed at $20^{\circ}C$ water then removed cryoprotectant in 3 steps. In each group, thawed blastocysts were cocultured with cumulus cells in YS medium containing 20% hFF for 18h and transferred into the uterus. The implantation rate was evaluated per transferred blastocysts and the pregnancy rate was evaluated per transfers. Results: The survival rate of vitrified group (74.5%) was higher than slow freezing group (68.0%), but not significant. When 98 thawed blastocysts of vitrification were transferred in 40 cycles, 19 pregnancies (clinical pregnancy rate; 47.5%) were established. One miscarriage occurred in the eighth week of pregnancy (ongoing pregnancy rate; 45.0%). 7 pregnancies were ongoing, 11 pregnancies went to term, and 16 healthy infants were born. The Implantation rate was 31.6%. These results were higher than those obtained by the slow freezing (clinical pregnancy rate; 40.3%, ongoing pregnancy rate; 32.5% and implantation rate; 25.3%), but not significant. Conclusion: Vitrification is a simple, quick and economical method when compared to slow freezing. It will be chosen as a good method of human embryo freezing in IVF-ET programs.

• Radiation Oncology Journal
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• v.14 no.3
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• pp.221-228
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• 1996

Purpose : We tried to evaluate the clinical characteristics, the treatment methods, the results of treatments, and the Patterns of failure in ovarian dysgerminoma retrospectively According to the results we would like to suggest the proper management guideline of stage la ovarian dysgerminoma patients who want to maintain fertility. Materials and Methods : Between 1975 and 1990, 34 patients with ovarian dysgerminoma were treated at the Yonsei University Hospital. The case records of these patients have been reviewed for presenting symptoms, treatment methods, local control and survival following treatment. Excluded from analysis were five patients with mixed ovarian germ cell tumors and gonadoblastomas (46,XY) Treatment results of the twenty nine patients were analysed by each treatment modality. Twenty one patients were treated with surgery and postoperative adjuvant radiotherapy (group 2). The other eight patients were treated with operation alone (group 2). The median age of twenty-nine patients was 23 years with a range of 8 to 39 years. Presenting symptoms were abdominal mass (20) pelvic discomfort or pain (5) et al. Radiotherapy was performed by 10MV LINAC or Co-60 teletherapy unit. The total radiation dose of the whole abdomen was 20-25 Gy/3weeks, 1-1.5 Gy/fraction with a boost to the whole pelvis 10-15 Gy/l-2weeks 1.8-2.0 Gy/fraction. Advanced stage disease (stage II or stage III) patients received prophylactic mediastinal and supraclavicular irradiation to a dose of 16-26 Gy. Median duration of follow-up of living patients was 80 months (range 13-201 months). Results : All of the twenty one patients of group 1 were alive without disease ($100\%$). Among the eight patients who were not treated with radiotherapy (group 2), six patients developed local recurrence. Four Patients referred with recurrent disease were treated with salvage radiotherapy. Three of four patients were salvaged and one Patient who had recurrent intra-abdominal disease died of progressed carcinomatosis at 11 months after salvage radiotherapy. The other two patients with recurrence were salvaged with chemotherapy (1 patient) or re-operation (1 Patient). Twenty eight patients remained alive without disease at last follow up, so the 5 year local control rate and 5 year overall survival rate for all groups were $96.6\%$ (28/29), respectively. Among thirteen patients with stage la unilateral tumors seven patients were treated with postoperative radiotherapy and the other six patients were treated with unilateral salpingo-oophorectomy alone. Five patients who did not received radiotherapy developed local failure but all of the recurrent ovarian dysgerminomas were salvaged with radiotherapy, chemotherapy or re-operation. So all the 13 patients with stage la ovarian dysgerminoma were free of disease from 20-201 months (median 80 months). Conclusion : The authors consider external irradiation to be an effective treatment as a complement to surgery in ovarian dysgerminoma. For those patients with disease presenting in stage la tumors who wish to maintain fertility, unilateral salpingo-oophorectomy alone may be curative and spare ovarian function considering excellent salvage rate of recurrent ovarian dysgerminoma in present study.