• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.142.2-142.2
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• 2016

The metal intercalation to an organic semiconductor is of importance since the charge transfer between a metal and an organic semiconductor can induce the highly enhanced conductivity for achieving efficient organic electronic devices. In this regard, the changes of the electronic structure of copper phthalocyanine (CuPc) caused by the intercalation of potassium are studied by ultraviolet photoemission spectroscopy (UPS) and density functional theory (DFT) calculations. Potassium intercalation leads to the appearance of an intercalation-induced peak between the highest molecular occupied orbital (HOMO) and the lowest molecular unoccupied orbital (LUMO) in the valence-band spectra obtained using UPS. The DFT calculations show that the new gap state is attributed to filling the LUMO+1, unlike a common belief of filling the LUMO. However, the LUMO+1 is not conductive because the ${\pi}$-conjugated macrocyclic isoindole rings on the molecule do not make a contribution to the LUMO+1. This is the origin of a metal-insulator transition through heavily potassium doped CuPc.

• Korean Journal of Head & Neck Oncology
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• v.16 no.1
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• pp.73-76
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• 2000

Neurilemmomas are uncommon benign tumors originating from the schwann cells of various cranial nerves, spinal nerves, and autonomic nerves. About 25% of the disease is found in the head and neck region and the most common single site of origin is known to be the acoustic nerve. However neurilemmomas of the peripheral segment of the lingual nerve are extremely rare neoplasms. We recendy experienced a case of a benign neurilemmoma of the lingual nerve and this case may be the second to be reported in the literature.

• Imaging Science in Dentistry
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• v.32 no.1
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• pp.49-53
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• 2002

Orofacial pain can be caused by intracranial disorders or can be musculoskeletal, vascular, internal derangemental, and neurologic in origin. The neurologic pain is derived from structural and functional disorders of nerve, and the trigeminal neuralgia is the typical manifestation. Trigeminal neuralgia is known from centuries ago, and is one of the most common pains in human. We present our experience with three patients who have trigeminal neuralgia. The first case is a 50-year-old female who had no specific evidence radiographically. Second is a 50-year-old male with microvascular compression on right trigeminal nerve. The third case is a 60-year-old female who had a neoplasm in cerebellopontine angle with associated mass effect.

• Imaging Science in Dentistry
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• v.32 no.1
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• pp.41-47
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• 2002

Osteochondroma is a benign lesion of osseous and cartilagenous origin. It is a relatively common benign tumor of the skeleton, occurring most often in the metaphyseal region of long bone. However, it is rare in the facial bones. Reported foci in the mandible were the condyle, coronoid process, and symphysis region. Synovial chondromatosis is an uncommon benign condition of unknown etiology which affects the articular joints. Foci of cartilage develop through metaplasia in the underlying connective tissue of the synovial membrane. These cartilagenous foci and fragments may undergo calcification and ossification. We experienced 4 patients with abnormal appearance of mandibular condyle. This report describes 3 cases of osteocondroma and 1 case of synovial chondromatosis of the mandibular condyle with review of the literature.

• Korean Journal of Head & Neck Oncology
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• v.9 no.1
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• pp.42-48
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• 1993

A group of 49 patients with neurogenic tumor in head and neck except intracranial tumor & Von-recklinghausen's disease was treated at the Department of Surgery. Presbyterian Medical Center during 12 years from January, 1980 to December, 1991. Of the 49 cases, 24 cases were neurilemmoma, 23 cases neurofibroma and 2 cases malignant schwannoma. The lateral cervical region was the commonest location of the neurogenic tumors, 24 cases (49%) arose from posterior triangle of neck and 12 cases from anterior triangle of neck. The origin of nerve was identified in 28 cases(57%). Cervical plexus(10 cases) and brachial plexus(7 cases) were most commonly affected. The most common site of neurogenic tumors arose from cranial nerve was anterior cervical triangle.

• Journal of Chest Surgery
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• v.11 no.3
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• pp.273-280
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• 1978

19 chronic pericarditis patients reviewed who were treated by surgical intervention in the Department of Thoracic and Cardiovascular Surgery, Chonnam University Hospital during the recent 10 years from January of 1968 to January of 1978. 2. There were 14males and 5 females in this series. Range of age varied from 110 days to 61 years. 2. There were two hospital death, one expired 2 days and another 3 days after the pericardiectomy. In both of them, myocardial damage by disease process seemed to be major contributing factor. 2. Clinical and histological study showed tuberculous origin in 8 cases, nonspecific chronic inflammatory changes in 6 cases and pyogenic infection cases in 5 patients. 2. The postoperative complications were observed in 6 cases, and the most common was cardiac arrhythmia and wound infection. 2. The extent of pericardiectomy should be confined to the left and right ventricles to correct the hemodynamic anomaly in general. The results of this procedure has been satisfactory in 89 percent of the cases. 2. Optimal myocardial function in cases of constritive pericarditis was the key to the successful outcome of this procedure.

• Journal of Chest Surgery
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• v.25 no.3
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• pp.330-334
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• 1992

Takayasu`s arteritis is a non-specific arteritis involving the aorta and its major branches. Because of the complexity in the feature of vessel involvement, it represents various clinical presentations according to the sites of involvement. In general, the medical and the surgical treatment of this progressive disease are known to be unsatisfactory but the surgical treatment can provide symptomatic relief and prolong life in selected cases. Recently we experienced one case of Takayasu`s arteritis involving the aortic arch and its major branches. A 45 year-old male patient admitted with the complaints of dizziness, headache, visual disturbance and coldness of upper extremities. Ascending aortogram revealed total occlusion of innominate artery and near total occlusion of left common carotid artery at the site of origin of both vessels. Under the clinical diagnosis of Takayasu`s arteritis, aorto-bicarotid-right subclavian bypass was performed. Postoperative course was uneventful and most of symptoms were relieved except mild residual visual disturbance.

• Journal of Yeungnam Medical Science
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• v.6 no.2
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• pp.271-277
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• 1989

There have been reported cases that the Krukenherg tumor had been primary ovarian carcinoma, But the Krukenberg tumor is generally known as one special type of metastatic ovarian carcinoma, which histologically consists of nest of mucin filled signet-ring cells in a cellular, nonneoplastic stroma. The most common gastrointestinal tract origin for Krukenberg tumor is the stomach, and the next frequent is the large intestine. Generally the Krukenberg tumor is difficult to diagnose and treat until somewhat enlarging its size. We experienced a case of the Krukemberg tumor on the remained ovary after the previous unilateral adnexectomy, which was metastasized from adenocarcinoma of stomach. We present this case with a brief review of literature.

• Journal of Korean Neurosurgical Society
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• v.44 no.6
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• pp.405-408
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• 2008

GBM is the most common primary brain tumor, but intraventricular GBM is rare and only few cases have been reported in the literature. The authors report a case of 64-year-old man who had a remote history of previous periventricular intracerebral hemorrhage. Brain computed tomography (CT) and magnetic resonance (MR) imaging showed an intraventricular lesion with inhomogeneous enhancement, infiltrative borders and necrotic cyst, and obstructive hydrocephalus. The patient underwent surgical removal through transcortical route via the bottom of previous hemorrhage site and the final pathologic diagnosis was GBM. We present a rare case of an intraventricular GBM with detailed clinical course, radiological findings, and pathological findings, and the possible origin of this lesion is discussed.

• Journal of the Korean Ceramic Society
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• v.31 no.12
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• pp.1513-1520
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• 1994

Mechanical properties of hot-pressed SiC whisker/Al2O3 composites were strongly dependent on the granular characteristics of mixed powder, which were controlled by co-dispersion condition, the existence of steric barrier on whisker surface, and granulating method, etc. Heat-treatment of SiC whiskers at $700^{\circ}C$ for 1 hr in air was very effective both for achieving dispersion stability of whiskers with PVA adsorption and for obtaining excellent mechanical properties of resulting composites. It is believed from the fractography of composites prepared with various whisker dispersion conditions that the most common fracture origin of Al2O3 agglomerate could be attributed to whisker clusters arising due to flocculation. Further improvement of mechanical properties of composites were achieved by hot pressing green tapes prepared by Doctor-blade process, which promoted two-dimensional random alignment of whiskers.