• 대한소아치과학회지
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• 제44권1호
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• pp.116-121
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• 2017

상악 제2유구치의 부가치근은 드물게 관찰된다. 본 증례보고에서는 두 증례를 통해 상악 제2유구치의 부가치근과 하방 영구 계승치의 변위 및 회전이 연관되었을 가능성에 대해 논의하였다. 상악 제2유구치의 치관 형태를 관찰함으로써 부가치근의 존재 가능성을 의심할 수 있으며, 부가치근이 존재하는 경우 영구 계승치의 맹출 양상을 주의 깊게 관찰해야 할 필요가 있을 것으로 사료된다. 만약 소구치 치배가 비정상적인 맹출 양상을 보인다면 선행 유치의 조기 발거 및 공간유지가 보존적인 치료법이 될 수 있다.

• 대한기계학회논문집B
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• 제28권10호
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• pp.1231-1237
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• 2004

Determination of geometric design parameters of a second-throat type annual supersonic ejector is described. Tested geometric parameters were primary nozzle area ratio, cross-sectional area of second-throat, L/D ratio of second-throat and primary flow injection angle. Varying these four geometric parameters, we build a test matrix made of 81 test conditions, and experimental apparatus was fabricated to accommodate them. For each test condition, the stagnation pressure of primary flow and the static pressure of the secondary flow were measured simultaneously along with their transition to steady operation and finally to unstarting condition. Comparing the performance curve of every case focused on starting pressure, the unstarting pressure and the minimum secondary pressure, we could derive correlations that the parameters have on the performance of the ejector and presented the optimal design method of the ejector. Additional experiments were carried out to find effects of temperature and mass flow rate of the secondary flow.

• 대한소아치과학회지
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• 제49권3호
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• pp.340-347
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• 2022

하악 제2소구치 치배의 원심 변위는 해당 치아의 매복 뿐만 아니라 하악 제1대구치의 맹출 경로를 방해하여 추가적인 맹출 지연을 야기할 수 있다. 이 증례 보고는 원심으로 변위된 하악 제2소구치로 인해 하악 제1대구치의 맹출 지연이 나타난 두 증례를 소개하고 있다. 원심으로 변위된 하악 제2소구치 치배의 근심 이동을 위해 선행 유치의 의도적 발거술을 시행할 수 있다. 하지만 제2유구치의 조기 상실 시 바람직하지 않은 하악 제1소구치의 원심 이소맹출이 나타날 수 있다. 하악 제1소구치의 바람직하지 않은 원심 이소맹출을 방지하면서 원심으로 변위된 하악 제2소구치 치배를 근심으로 이동시키기 위해 하악 제2유구치의 편측치아절제술 및 순차적 발거를 수행하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.769-773
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• 2013

Background: A literature review on 1,104,269 cancer patients concluded that the prevalence of multiple primary malignancies (MPM) is between 0.73% and 11.7%. MPMs seem to have higher incidence than that influenced by hazard only. The purpose of this study was to investigate clinically useful information for effective screening for synchronous and metachronous second primary cancers and to identify a potential surveillance protocol. Materials and Methods: Using statistical and epidemiological indicators we evaluated the patients with MPMs (double locations) admitted to Dr. Abdurrahman Yurtarslan Ankara Oncology Education and Research Hospital between 1981 and 2010. Results: Out of the 130 cases, 24 (18.4%) were synchronous while 106 cases (81.6%) were metachronous tumours. Mean interval time from first to second primary cancers was 4.65 years (0-27 years). The most frequent malignant associations were breast-breast, breast-endometrium and breast-ovary. Both primary and secondary tumors tended to be in an advanced stage explained by the low compliance of the patients to follow-up. Conclusions: The possibility that MPMs exist must always be considered during pretreatment evaluation. Screening procedures are especially useful for the early detection of associated tumors, whereas careful monitoring of patients treated for primary cancer and a good communication between patients and medical care teams should ensure early detection of secondary tumors, and subsequent appropriate management.

• 대한두경부종양학회지
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• 제15권2호
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• pp.162-165
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• 1999

Background and Objectives: Multiple primary tumors of the upper aerodigestive tract are not unusual. We examined head and neck cancer patients to discover the presence of second primary cancer in their upper gastrointestinal tract, using esophagogastroscopy. Materials and Methods: Endoscopic examination of the upper gastrointestinal tract was performed on 51 patients whose head and neck cancers were treated at department of therapeutic radiology from August 1996 to April 1999. Two of all patients had been studied by barium swallowing study. In 51 patients, twenty-four had a primary tumor in the larynx, 8 in the oropharynx, 6 in the nasopharynx, 6 in the oral cavity, 6 in the hypopharynx, and 1 in the nasal cavity. Endoscopically pathologic lesions were biopsied. In control group, endoscopy was performed on 1097 patients who didn't complain any symptoms. Results: Endoscopy showed early malignant lesions in 4 cases(7.7%). Histology of esophageal cancers showed squamous cell carcinoma. Malignant lesions of stomach in 2 cases were histologically identified as adenocarcinoma. Two esophageal cancers occurred in patients whose primary lesions had oropharynx and hypopharynx. Two cases of gastric cancer were also accompanied by oropharynx and hypopharynx. The incidence of second primary cancer was 2 in oropharynx and 2 in hypopharynx. In all cases, second primary cancers were found simultaneously. In control group, 9(0.8%) of 1097 patients were confirmed as early esophageal and gastric cancers. Conclusion: The majority of esophageal and gastric cancer detected by endoscopy were early stage in both head and neck cancer and control group. The incidence of esophageal and gastric cancer of head and neck cancer patients was 10 times as high as that of control group. Although followup period was short, all second primary cancers were detected simultaneously. We would recommend that endoscopic evaluation be included in the workup and followup of all patients with newly diagnosed head and neck cancer.

• Journal of Plant Biology
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• 제26권4호
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• pp.207-216
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• 1983

Mature embryo and developing seedlings of Ginkgo biloba L. were embedded in a paraplast and serially sectioned at 10${\mu}{\textrm}{m}$ to examine vascular differentiation and vascular transition. Procambium and protophloem formed a continuous system along the epicotylhypocotyl root axis and cotyledons in mature embryo, whereas protoxylem was differentiated discontinuously in the cotyledons and rarely in the upper hypocotyl. The traces of the first and second leaf primordia apeared almost at the same time oppositely to each otehr at the epicotyl and alternately with the cotyledon traces in the upper hypocotyl. The trace differentiated bidirectionally toward the epicotyl and root tips. the young root initially formed a diarch xylem. Then, as the traces of the first and second leaves were superimposed, the diarch xylem. Then, as the traces of the first and second leaves were superimposed, the diarch xylem of the root was changed totriarch and tetrarch xylem, respectively. On the formation of primary vascular system of Ginkgo biloba, it is suggested that the primary phloem forms a continuous system throughout the seedling, whereas the primary xylem of the epicotyl is formed independently from that of the root-hypocotyl cotyledon system.

• 대한소아치과학회지
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• 제35권2호
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• pp.297-304
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• 2008

본 연구는 제1유구치의 조기 상실 시공간 변화에 대한 분석을 위하여 3-Dimensional Laser Scanner를 이용하여 그 유용성을 평가하고자 하는 예비논문이다. 6세-8세 사이의 제1대구치가 맹출하여 확실한 교합 관계를 이루는 혼합치 열기 어린이 중 편측 제1유구치의 조기 발치가 필요한 6명의 발치 전 후의 모형을 이용하여 다음과 같은 결과를 얻었다. 1. 유구치 공간변화는 상악은 실험군과 대조군 모두 현저한 감소를 보이지 않았고, 하악은 실험군에서 3명 중 2명에서 공간감소가 관찰되었다. 2. 치열궁 너비, 치열궁 둘레는 초기모형과 최종모형에서 비슷한 값을 보였다. 3. 협설측 경사도 변화는 유견치에서는 상하악 모두 특별한 경향을 보이지 않았으며, 제2유구치는 상악은 실험군과 대조군이 유사하였고, 하악에서는 3명중 2명에서 실험군이 더 큰 설측경사도 변화를 보였다. 제1대구치는 하악에서 실험군이 더 큰 설측경사도 변화가 관찰되었다. 4. 근원심 경사도 변화 측정에서 유견치는 상하악 모두 특별한 경향이 관찰되지 않았고 제2 유구치의 경우 하악에서 실험군이 더 큰 근심경사도 증가가 보였다. 제1대구치는 상악에서 실험군, 대조군 모두 원심 경사도가 증가되었다.

• 대한종양외과학회지
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• 제14권2호
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• pp.83-88
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• 2018

Purpose: Double primary colorectal cancer (CRC) and gastric cancer (GC) represent the most common multiple primary malignant tumors (MPMT) in Korea. The recognition and screening of hidden malignancies other than the primary cancer are critical. This study aimed to investigate the clinicopathologic characteristics and survival rates in patients with synchronous or metachronous double primary CRC and GC. Methods: Between January 1994 and May 2018, 11,050 patients were diagnosed with CRC (n=5,454) or GC (n=5,596) at Gil Medical Center. MPMT and metastatic malignant tumors were excluded from this study. A total of 103 patients with double primary CRC and GC were divided into two groups: the synchronous group (n=40) and the metachronous group (n=63). The incidence, clinicopathologic characteristics, and survival rate of the two groups were analyzed. Results: The incidence of synchronous and metachronous double primary CRC and GC was 0.93%. Double primary CRC and GC commonly occurred in male patients aged over 60 years with low comorbidities and minimal previous cancer history. There were significant differences between the synchronous and metachronous groups in terms of age, morbidity, and overall survival. Metachronous group patients were 6 years younger on average (P=0.009), had low comorbidities (P=0.008), and showed a higher 5-year overall survival rate (94.8% and 61.3%, P<0.001) in contrast to synchronous group. Conclusion: When primary cancer (CRC or GC) is detected, it is important to be aware of the possibility of the second primary cancer (GC or CRC) development at that time or during follow-up to achieve early detection and better prognosis.

• 대한소아치과학회지
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• 제29권2호
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• pp.139-145
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• 2002

유치에서는 영구치에 비해 법랑질의 두께가 얇고 약하며 상대적으로 큰 치수강으로 인하여 단시간에 치아우식증이 치수까지 이환되며, 외상 또는 치과치료 중 갑작스런 움직임으로 인하여 치수가 노출되는 경우가 빈번하다. 이러한 이유로 어린이에서의 치수처치는 필수적이며, 유치에서 치수치료의 목적은 감염된 치수조직을 제거하여 동통을 완화시키는 것 이외에도 크게는 치열궁을 보존하여 저작기능을 보호하고, 미래의 영구치열이 적절한 교합관계를 이루게 하는데 있다. 유치열에서 성공적인 치수치료를 위해서는 유치 치수의 형태, 유치 근관의 해부학적 형태, 치근형성, 그리고 유치 치근의 흡수와 관련된 특별한 문제점들에 대한 이해를 필요로 한다. 상악 대구치와 마찬가지로 상악 유구치의 근심 치근이 형태에 있어서 가장 큰 변이를 보인다고 알려져 있으며, 이 치근 내에 존재하는 모든 근관을 처치하지 못한다면 결국 치수치료는 실패할 것이다. 본 증례는 근관치료 중이거나 후에 지속적인 동통이나 근관 내 출혈이 지속되는 경우에서 상악 유구치의 근심협측치근의 제 2근심협측근관을 발견하고 처치한 후 임상증상 및 동통이 사라지고, 양호한 예후를 보였다. 또한 발거된 상악 유구치를 대상으로 한 조사 결과 상악 제 1유구치는 35개 증 8개(22.8%), 상악 제 2유구치는 33개 중 22개(66.6%)의 치아에서 제 2근심협측근관이 발견되었으며. 이는 상악 유구치의 근심협측치근 내에 두 개의 근관이 존재할 가능성이 높다는 것을 의미한다.

• 대한소아치과학회지
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• 제24권4호
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• pp.776-780
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• 1997

Patient with alveolar abscess due to dental caries with severe alveolar bone loss, severe tooth mobility, root resorption need extraction of tooth because it is impossible to carry out pulp treatment and restoration by using conventional method. Early loss of primary molar might cause masticatory interference, extrusion of opposing tooth, problem in maintaining space and interference on eruption of permanent tooth. Especially, early loss of primary second molar before the eruption of permanent first molar might cause space closure by mesially erupted permanent first molar and impaction of second premolar. In such a case, distal shoe space maintainer and removable space regaining appliance was the first choice of treatment. But, distal shoe space maintainer need precise adaptation and might cause chronic inflammation if the oral hygiene is poor. In a case using removable space regaining appliance, patient's cooperation is most important. If the distal root of primary second molar is comparably sound and alveolar abscess with alveolar bone loss is localized at mesial root, hemisection should be carried out for precise guide to eruption of the permanent first molar, restoration of masticatory fuction and solution to the discomfort of the patient