• The Korean Journal of Ecology
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• v.27 no.6 s.122
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• pp.369-373
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• 2004

The water strider, Gerris paludum insularis, was reared in a growth cabinet at two constant temperatures and ${\approx}20^{\circ}C$ under a 16:8 (L:D) photoperiod. Differences in head width among three temperatures of ${\approx}20^{\circ}C,\;25^{\circ}C\;and\;30^{\circ}C$ in G. paludum insularis, were compared. Temperature affected growth of head width of G. paludum insularis. There were highly significant differences among head width for three temperature regimes and the immature stages. It was found that head width is greater in $30^{\circ}C$ than $25^{\circ}C\;and\;{\approx}20^{\circ}C$. The growth quantity of the head width in ${\approx}20^{\circ}C$ shows the slowest increase, and $25^{\circ}C\;and\;30^{\circ}C$ were gradually increased in that order. The maximum ratio of growth quantity by each stage is in the first instar in all regimes. The growth rates of all regimes show an increase pattern.

• Journal of Sericultural and Entomological Science
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• v.39 no.2
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• pp.174-179
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• 1997

The larval head capsule width, larval weight and length of mulberry longicorn beetle, Apriona germari Hope were measured when the larvae were exuviated in artificial diet rearing. The larval head capsule width from the 1st to the 12th instar was ranged from 0.12 to 0.69 cm, and growth ratio of each instar was significantly high between the 1st and the 2nd instars. The fitness to Dyar's law for the larval head capsule width was 87.6%. When the logarithum of the larval head capsule width is plotted against the number of instars, the calculated regression line was LogY=0.12086+0.06998X and Dyar's constant was 1.18. The larval weight was increased with larval developmental stages, and the coefficient of variation of larval weight was apparently high. But the calculated regression line was LogY=-0.91592+0.25959X and Dyar's constant was 1.25. The growth ration of the larval length was clearly high between the 2nd and the 3rd instars, and that of larvae from the 4th instar was decreased. The calculated regression line was LogY=-0.16932+0.09841X and Dyar's constant was 1.25. In conclusion, our results suggested that the larvae growth of mulberry longicorn beetle appeared to be highly related in the larval head capsule width, larval weight and length.

• Korean Journal of Bronchoesophagology
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• v.8 no.1
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• pp.35-41
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• 2002

Background and Objectives : Angiogenesis within malignant tumors has been considered to be essential for the growth and expansion of cancer cells, especially for solid tumors, and has been implicated in the overall growth and metastases of tumors. Such angiogenesis within tumors depends upon the secretion of vascular growth factor to allow the growth of newly formed vessels from peripheral tissue into the malignant tumor. %n, an exploration of the relations between cancer cells and vascular growth factors is absolutely critical to understanding the growth of malignant tumors. According to recent reports, vascular endothelial growth factor(VEGF) has been found to play a role in lymphatic metastases, tumor recurrence and survival in various human tumors. To evaluate the role of VEGF in head and neck squamous cell carcinoma(HNSCC) we performed this study. Materials and Methods : We examined the expression of VEGF and microvessel density in 39 HNSCC by immunohistochemistry and correlated them with various clinical data such as stage, cervical lymphatic metastasis, recurrence, and overall survival. Results : The expression of VEGF was not correlated with overall stage, T stage and N stage. There was no statistical correlation between the expression of VEGF and recurrence in the Primary site, cervical lymph node, and the distant metastases. There was no statistical correlation between the expression of VEGF and microvessel density. Conclusion : Based on these results, it is suggested that the expression of vascular endothelial growth factor is not a major prognostic factor for head and neck squamous cell carcinoma. Further studies are needed to evaluate significance of VEGF expression in head and neck squamous cell carcinoma.

• Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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• v.61 no.12
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• pp.681-685
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• 2018

Background and Objectives This study was performed to evaluate the long-term effect of adenotonsillectomy on childhood growth by examining preoperative growth status and presenting symptoms. Subjects and Method One hundred and four patients who underwent adenotonsillectomy from January to December 2009 were enrolled in this study. Clinical data were collected from medical record reviews and through the administered questionnaire. We investigated symptoms and growth changes during 5 years following the surgery. Results The mean age of patients was $6.0{\pm}1.94$ years (range, 3-10), with the male to female ratio of 62:42. Pre-operative symptoms were significantly improved after the surgery. The mean pre-operative height and weight percentiles were $53.6{\pm}27.4$ and $59.6{\pm}29.2$ at initial evaluation, and $67.1{\pm}26.4$ and $59.6{\pm}28.6$ at 5 years post adenotonsillectomy (p<0.001, p=0.989), respectively. An increase in height percentile was more prominent in patients whose pre-operative height percentile was less than 50 compared to those with a percentile of 50 or more (p<0.001). Weight percentile was significantly increased in those with the pre-operative weight percentile of less than 50 and decreased in patients with a percentile of 50 or more. Conclusion Adenotonsillectomy has a positive effect on height growth in children with adenotonsillar hypertrophy, especially in patients whose height percentile is less than 50. Weight gain also can be expected in preoperative low-weight children.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.2
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• pp.154-163
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• 2000

Growth factors and the receptors play an important role in the regulation of the growth and development of mammalian cells. In particular, epidermal growth factor is a polypeptide with potent mitogenic activity that stimulates proliferation of various normal and neoplastic cells through the interaction with its specific receptor(EGFR). EGFR has been described as a parameter of poor prognosis in many human neoplasms such as breast, bladder, and vulvar cancers. The objectives of this study are the evaluation of the expression of EGFR and cell cycle analysis in the head and neck squamous cell carcinomas(SCC), and the evaluation of the correlation between clinico-patholgic features and expression of EGFR and S-phase fraction. 37 head and neck squamous cell carcinoma specimens were evaluated for expression of EGFR by Western blot analysis and S-phase fraction by cell cycle analysis using the flow cytometry. The obtained results were as follows : 1. The expressions of EGFR were observed in 20 specimens(54%) among 37 head and neck SCC specimens. In case of oral SCC, 15 specimens(56%) out of 27 specimens were observed, and in case of nasopharyngeal SCC 5 specimens(50%) out of 10 specimens. 2. There was no correlation between clinical features(location, stage) of head and neck SCC and expression of EGFR (p>0.05). 3. There was a significant correlation between histo-pathological differentiation of head and neck SCC and expression of EGFR (p<0.02). 4. There was a significant correlation between expression of EGFR and S-phase fraction of cell cycle in the head and neck SCC (p<0.05). The above results suggest that expression of EGFR and S-phase fraction of cell cycle are adjunctive prognostic marker in the head and neck squamous cell carcinomas.

• The korean journal of orthodontics
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• v.24 no.2
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• pp.319-329
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• 1994

This study was carried out to research the adaptation patterns of head posture after activator therapy in functional class III malocclusion patients. For this purpose, 29 functional class III malocclusion patients, from the ages of 8 to 13 years old, were used. 1, Increse in capacity of oral cavity capacity were found in all the samples, but craniocervical angulation were varied into incresed group and decreased group after activator therapy. 2. Head posture exhibited the compensatory adaptation in the relative growth increments of the vertical dimension, ALFH and PLFH. 1) A group with more PLFH and less sagittal angle showed relatively small growth increment in PLFH during the treatment period, thus craniocervical angulation was increased. 2) A group with less PLFH and more sagittal angle showed relatively great growth incrmenet in PLFH during the treatment period, thus craniocervical angulation was decreased.

• Korean Journal of Head & Neck Oncology
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• v.18 no.2
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• pp.135-141
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• 2002

Backgrounds and Objectives: Metastasis is a complex multistep process that requires sequential interactions between the invasive cell and the extra-cellular matrix. Transforming growth factor-${\beta}1$ ($TGF-{\beta}1$) is a multifunctional regulator of cellular differentiation, motility and growth. Loss of sensitivity to the growth inhibitory effects by $TGF-{\beta}1$ plays important roles in neoplastic progression. The aim of this study was to investigate the role of $TGF-{\beta}1$ in the neoplastic invasion and metastasis through matrix metalloproteinase (MMP) of laryngeal cancer cell lines. Material and Methods: Two laryngeal cancer cell lines, SNU-899 and SNU-1076 were treated with recombinant $TGF-{\beta}1$, and the expression of MMP-2 and MMP-9 was immunohistochemically evaluated and gelatinase activity was studied by gelatin zymogram. Results: The cell growth inhibition was evident on 4th days after 1ng/ml and 10ng/ml $TGF-{\beta}1$ treatment. The expressions of MMP-2 and MMP-9, and their gelatinase activities were increased in dose-dependent manner. Conclusion: $TGF-{\beta}1$ treatment in laryngeal cancer cell lines induces the expression of MMP-2 and MMP-9, thus playing a role in the digestion of extracellular matrix gelatin.

• Korean Journal of Head & Neck Oncology
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• v.20 no.1
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• pp.13-18
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• 2004

Objectives: Cancer lethality is usually the result of local invasion and metastasis of neoplastic cell from the primary tumor. Because of their ability to degrade extracellular matrix components, matrix metalloproteinases (MMPs) and basic fibroblast growth factor (bFGF) have been implicated in the breakdown of basement membrane and underlying stroma, thereby facilitating tumor growth and invasion. It has been well established that MMPs and bFGF expression correlate with cervical lymph node metastasis, but studies on expression in the metastatic cervical lymph node itself are not enough. We have analyzed matrix metalloproteinases (MMPs) and basic fibroblast growth factor (bFGF) in squamous cell carcinoma of the head and neck and metastatic cervical lymph node, and evaluated their relationship and clinicophathologic significance. Material and Methods: 20 cases of squamous cell carcinoma of the head and neck were entered on the study of immunohistochemical stains for MMP-9 and bFGF in the obtained tissue from primary tumor and metastatic cervical lymph node. We analyzed the relationship between MMP-9, bFGF expression of the primary tumor and metastatic node with age, sex, T-stage, N-stage, histologic grade, pathologic stage and disease free survival. Results: Expression of MMP-9 and bFGF in cancer cell and metastatic lymph node was higher than that in normal cell and lymph node. According to histologic differentiation, expression of MMP-9 of the metastatic cervical lymph node was higher than primary tumor. Considering to other clinicopathologic factor, no statistical significance was seen in MMP-9 and bFGF. Conclusion: We found that expression of MMP-9 is higher in the metastatic lymph node than primary tumor in the poorly differentiated squamous cell carcinoma. But we don't find out the statistical significance in relation between bFGF and clinical factors. So we guess that some different mechanism of MMP-9 and bFGF in Head & Neck squamous cell carcinoma exist. Further studies will be necessary to establish their pathogenesis in the Head and Neck cancer.

• The Korean Journal of Ecology
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• v.6 no.2
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• pp.106-113
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• 1983

The growth of Korean axolotl., Hynobius leechii, was analyzed in natural water as control group and in six copper ion groups contaminated by 0.1, 0.2, 0.3, 0.4, 0.5, 0.6 ppm of copper ion. The copper ion checks the growth of the axolotl. The axolotl was not survived during 30 days in the copper ion of 0.3ppm, and, in the 0.4ppm the axolotl was not survived during 10 days after hatch. The growth of head width and body length show a convexing increase pattern, while that of hind leg shows a concaving increase pattern. The copper ion checks the development of hind leg. In the growth quantity of head width, body length and hid leg, that of natural water show the most rapid increase pattern, and copper ion groups of 0.1, 0.2, 0.3ppm follow in that order. The coefficient of relative growth($\alpha$) of control group is the greater value, and the copper ion groups of 0.1, 0.2, 0.3ppm follow in that order. The contaminated groups show the negative allometry in the relative growth of the containated groups to the natural water. Body length shows positive allometry, while hind leg shows negative allometry in the relative growth to head width.

• Nuclear Engineering and Technology
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• v.51 no.4
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• pp.1060-1068
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• 2019

This work aims to establish a model of a primary water stress corrosion crack growth rate of Alloy 690 material for the head penetration nozzles of Korean pressurized water reactors. The test material had an inhomogeneous microstructure with bands of fine-grains and intragranular carbides in the matrix of coarse-grains, which was similar to the archive materials of the head penetration nozzles. The crack growth rate was measured from the strain-hardened materials as a function of the stress intensity factor in simulated primary water at various temperatures and dissolved hydrogen contents. The effects of strain-hardening, temperature, and dissolved hydrogen on the crack growth rate were analyzed independently, and were then introduced as normalizing factors in the crack growth rate model. The crack growth rate model proposed in this work provides a key element of the tools needed to assess the progress of a stress corrosion crack when detected in thick-wall Alloy 690 components in Korean reactors.