• 대한두경부종양학회:학술대회논문집
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• 1993.11a
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• pp.274.1-274.1
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• 1993

• Journal of Life Science
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• v.21 no.4
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• pp.529-533
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• 2011

Metallothioneins (MT) are a group of low-molecular weight, cysteine-rich, intracellular proteins that are encoded by a family of genes containing at least 10 functional isoforms in human. The expression and induction of these proteins is associated with protection against DNA damage, oxidative stress, and apoptosis. Many studies have shown increased expression of MT in various human tumors, whereas MT is down-regulated in certain tumors such as hepatocellular carcinoma and liver adenocarcinoma. Hence, the expression of MT is not universal to all human tumors but may depend on the differentiation status and proliferative index of tumors, along with other tissue factors and gene mutations. Using Northern blot analysis, we found that laminin induced expression of MT-1 in HSG and PC12 cells, which can be differentiated by laminin, but had no effect on MB-231, MDA-435, and PC-3 cells, which cannot be differentiated by laminin. In addition, we analyzed the expression level of the MT-1 gene in five prostate cancer cell lines possessing different metastatic potential. The expression of MT-1 in normal and less malignant cells (RWPE-1 and WPE1-NA22) was high and up-regulated by laminin, whereas the expression of MT-1 in WPE1-NB14, WPE1-NB11, and WPE1-NB26 cells (malignant) was extremely low and not elevated by laminin. These results suggest that the MT-1 gene is involved in laminin-mediated differentiation and affects the metastatic potential of tumor cells.

• Tuberculosis and Respiratory Diseases
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• v.43 no.4
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• pp.519-526
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• 1996

Background : Clinical and Radiographic studies to differentiate benign from malignant pulmonary nodules have previously focused on clinical status and the morphologic and the computed tomographic attenuation characteristics of the lung nodules. Distinctive differences in the vascularity and pathophysiology of malignant versus benign pulmonary nodules were identified. We evaluated the diagnostic method for differentiating malignant from benign solitary pulmonary nodule by contrast enhancement on the spiral CT. Method : Sixteen patients with solitary pulmonary nodule were examined(Tuberculoma 8, primary lung cancer 8). Serial thin section on the spiral CT was performed before and after(45second, 2min, 5min) the onset of the injection of 100mL of nonionic contrast material(2mL/sec). Results : There was no difference in size of nodule and pre-contrast CT number (Hounsfield unit) between benign and malignant nodules. At forty-five second after the onset of the injection, malignant neoplasms($19.6{\pm}7.9$ HU) enhanced significantly more than tuberculomas($4.9{\pm}9.4$ HU, p=0.008). At 2minute and 5 minute after, malignant neoplasms($34.0{\pm}19.2$HU, $34.0{\pm}15.4$HU) enhanced significantly more than tuberculomas ($6.7{\pm}9.7$HU, p=0.007 and $7.7{\pm}11.5$HU, p=0.011). On cut-off value 20HU(contrast enhancement) 2minute after the injection of contrast media, sensitivity was 87% and specificity was 87%. No correlation between the contrast enhancement and size of the nodules was observed. Conclusion : Studies with the use of an intravenously administered noniodinated contrast medium in examining the enhancement properties of lung nodules was performed. The contrast enhancement was useful in differential diagnosis of solitary pulmonary nodules.

• Journal of Korean Neurosurgical Society
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• v.30 no.11
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• pp.1340-1344
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• 2001

This is a rare case of cerebral metastasis from malignant fibrous histiocytoma(MFH) of the soft tissue. A 62-year-old man underwent craniotomy for resection of multiple intracerebral masses under the impression of metastatic brain tumor with unknown primary site. Preoperative investigation failed to detect any extracranial lesion. At six months after the operation and whole brain radiotherapy, right shoulder mass was detected to grow and excised. Specimen from the brain and shoulder lesions revealed identical pathological findings of malignant fibrous histiocytoma except existence of glial fibrillary acidic protein(GFAP)-positive cells only in brain lesions. Palliative radiotherapy was performed for subsequently developing metastatic lesions in skeletal system. At twelve months after initial diagnosis recurrent lesion at right shoulder was detected and chemotherapy is given. This case is unique because metastatic brain lesion from MFH is rare and also cerebral metastasis as an initial manifestaion of MFH has not been reported before. Another important finding is that there was expression of GFAP only in brain lesions but not in extracranial primary site lesion. Although the presence of GFAP-positive cells is thought as one of characteristic histological findings of primary intracrainal MFH, our observation supports the hypothesis that GFAP-positive cells in primary intracranial MFH may be nonneoplastic astrocytes secondarily involved by MFH.

• Journal of the Korea Society of Computer and Information
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• v.27 no.5
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• pp.149-156
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• 2022

Recently, there have been many reports of document-type malicious code injecting malicious code into Microsoft Office files. Document-type malicious code is often hidden by encoding the malicious code in the document. Therefore, document-type malware can easily bypass anti-virus programs. We found that malicious code was inserted into the Visual Basic for Applications (VBA) macro, a function supported by Microsoft Office. Malicious codes such as shellcodes that run external programs and URL-related codes that download files from external URLs were identified. We selected 354 keywords repeatedly appearing in malicious Microsoft Office files and defined the number of times each keyword appears in the body of the document as a feature. We performed machine learning with SVM, naïve Bayes, logistic regression, and random forest algorithms. As a result, each algorithm showed accuracies of 0.994, 0.659, 0.995, and 0.998, respectively.

• Journal of Chest Surgery
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• v.43 no.2
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• pp.217-220
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• 2010

Pleomorphic adenoma is also called a mixed tumor and it most commonly occurs in the salivary gland. This neoplasm has a low grade malignant potential, but it may also show aggressive clinical behavior like recurrence or metastasis. We report here on a case of a tumor that was confirmed to be primary pulmonary carcinoma ex-pleomorphic adenoma by the pathologic examination after complete resection, and it had the characteristics of malignant neoplasms, such as multiple metastases.

• Korean Journal of Head & Neck Oncology
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• v.17 no.1
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• pp.48-51
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• 2001

Sclerosing rnucoepidermoid carcinoma with eosinophilia(SMECE)는 1991년 Chan 등이 처음 보고한 이후로 현재까지 전세계적으로 단 17예 만이 보고된 매우 희귀한 갑상선 암종이다. 조직학적으로는 종양 내에 일부 점액성 세포와 증식된 상피성 세포들을 관찰할 수 있고, 조직내 호산구성 세포들이 자주 관찰된다. 대부분의 기질은 밀집된 섬유성 조직으로 구성되어 있으며, 하시모토 갑상선염이 동반되어 있는 것이 특장적이다. 종양의 악성도는 최초 보고인 Chan 등에 의하면 국소 재발 및 원격전이를 거의 하지 않는 예후가 좋은 암종으로 보고되었는데, 이후 여러 문헌에서 국소 침윤, 국소 재발, 원격 전이 및 사망이 발생하여 예후가 매우 불량했던 증례들을 보고한 바 있어 악성도에 대한 시각은 달라지고 있다. 본 저자들은 최근 병리적 진단이 매우 어려웠고, 국소침윤과 림프절 전이 소견을 보였으며, 수술 후 빠른 시일 내에 급속히 재발하였던 악성도가 매우 높은 sclerosing mucoepidermoid thyroid carcinoma with eosinophilia (SMECE) 1예를 경험하였기에 문헌고찰과 함께 보고하는 바이다.

• Convergence Security Journal
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• v.14 no.4
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• pp.61-71
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• 2014

In recent years, malwares in Android smartphones are becoming increased explosively. Since a great deal of appsare deployed day after day, detecting the malwares requires commercial anti-virus companies to spend much time and resources. Such a situation causes malwares to be detected after they have become already spread. We propose a scheme called TAU that dynamically tracks application behaviors to specify apps with potential security risks. TAU keeps track of how a user's interactions to smartphones incurs the app installation, the route of app spread, and the behavior of app execution. This tracking specifies apps that have the possibility of attacking the smartphones using the drive-by download and update attack schemes. Moreover, the tracked behaviors are used to decide whether apps are repackaged or not. Therefore, TAU allows anti-virus companies to detect malwares efficiently and rapidly by guiding to preferentially analyze apps with potential security risks.

• The Journal of the Korean dental association
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• v.27 no.8 s.243
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• pp.697-702
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• 1989

악성종양은 상피성의 암종(carcinoma)과 결체직성의 육종(sarcoma)으로 분류된다. 최근 암환자의 발생은 점차 증가되는 추세이며, 우리나라에서도 사망원인 중 뇌졸증 다음으로 암이 차지하는 비율이 높다. 이러한 암은 침윤성(infiltrative)인 성장으로 인하여 인접 정상조직을 급격히 파괴시키며, 해당 임파절을 따라 신체 다른 부위로 전이(metastasis)된다. 임파절에 전이되기 전에 조기발견된 암은 70%의 5년 생존률을 보이는 반면, 임파절에 전이된 후에 발견된 암은 30%의 5년 생존률을 보인다. 따라서 암의 성공적인 치료를 위해서는 이의 조기발견이 매우 중요하다고 할수 있다. 그러나 불행하게도 많은 환자가 이미 병소가 상당히 진행된 상태에서 내원하기 때문에 이의 근치가 어려우며, 예후 또한 좋지 않다. 이러한 암을 조기발견하기 위해서는 환자 자신의 관심뿐만 아니라 치과의사의 세심한 검진이 필요하리라 생각된다.

• The Journal of the Korean bone and joint tumor society
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• v.8 no.1
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• pp.12-19
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• 2002

Purpose : Giant cell tumors(GCT) sometimes undergo malignant transformation after the radiotherapy, but very rarely do without radiotherapy. We reviewed the clinical experiences of the malignant transformation of GCT to suggest the guidelines for diagnosis and treatment of them. Materials and Methods : We examined four patients of pathologically proven malignant transformation of GCT, which occurred after the operative treatment alone without radiation, from September 1985 to January 2001. The mean follow-up period after the malignant transformation was 2.4 years(range, 1.3~4 years). Results : The mean time-interval from the initial diagnosis to the malignant transformation was 6.9 years(range, 2.2~13.5 years). The locations of tumors were soft tissues of proximal upper arm, proximal femur, distal femur and proximal tibia. The histology of malignant GCT was osteosarcoma in 3 cases and malignant fibrous histiocytoma in 1 case. Local recurrence developed in 1 patient and the pulmonary metastasis developed in 3 patients which transformed to osteosarcoma. Conclusion : Thorough sampling of the surgical specimen appears to be a very important factor for diagnosing the malignant transformation of GCT. In case of suspicion of malignancy in radiographs, the incisional biopsy should be followed by definite treatment rather than the improper resection.