• Asian Pacific Journal of Cancer Prevention
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• 제16권4호
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• pp.1507-1513
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• 2015

Pemetrexed is an antifolate agent which has been used for treating malignant pleural mesothelioma and non small lung cancer in the clinic as a chemotherapeutic agent. In this study, pemetrexed inhibited cell growth and induced G1 phase arrest in the A549 cell line. To explore the molecular mechanisms of pemetrexed involved in cell growth, we used a two-dimensional polyacrylamide gel electrophoresis (2-DE) proteomics approach to analyze proteins changed in A549 cells treated with pemetrexed. As a result, twenty differentially expressed proteins were identified by ESI-Q-TOF MS/MS analysis in A549 cells incubated with pemetrexed compared with non-treated A549 cells. Three key proteins (GAPDH, HSPB1 and EIF4E) changed in pemetrexed treated A549 cells were validated by Western blotting. Accumulation of GAPDH and decrease of HSPB1 and EIF4E which induce apoptosis through inhibiting phosphorylation of Akt were noted. Expression of p-Akt in A549 cells treated with pemetrexed was reduced. Thus, pemetrexed induced apoptosis in A549 cells through inhibiting the Akt pathway.

• Journal of Radiation Protection and Research
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• 제22권4호
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• pp.289-298
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• 1997

중성자 수분함량 측정기의 개발에 있어서 중성자 계측값과 흙속의 수분함량에 대한 관계식을 유도하기 위해서는 공시체 제작 등의 많은 실험을 통해 유도한 교정식이 필요하다. 또한 공시체 제작 및 측정실험의 통계적 오차를 줄이기 위해서는 많은 시간과 노력이 필요하다. 하지만 몬테카를로방법을 사용한 전산코드를 이용하여 수행할 경우 시간과 노력을 줄일 수 있을 뿐만 아니라, 보다 일반적인 흙에 대한 교정식을 얻을 수 있다. 본 연구에서는 중성자의 수송문제를 계산하는데 유용한 MCNP4A 전산코드를 이용하여 실제 실험을 모사하였다. 또한 모사결과를 공시체를 제작하여 실험한 결과와 비교하였다. 비교결과 실제실험의 결과와 모사 범위 내에서 일치함을 알 수 있었다. 중성자 수분함량 측정기의 교정식 도출 및 교정상수를 결정하기 위해 적용할 수 있음을 알 수 있었다. 또한 수분함량 측정기의 계측값에 영향을 미치는 인자중의 하나인 흙의 건조밀도 변화에 대한 영향을 살펴보았다.

• 한국전자통신학회논문지
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• 제13권4호
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• pp.705-712
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• 2018

위상배열안테나는 빔 조향 각도에 따라 방사 특성이 변화한다. 모노펄스 추적 시스템은 합 및 차신호의 방사특성을 기반으로 추정 각을 산출하는 시스템이다. 따라서 위상배열안테나를 이용한 모노펄스 추적 시스템의 경우, 빔 조향 각도에 따라 모노펄스 비율 곡선이 변화하기 때문에 추적정확도가 낮아지는 문제가 발생한다. 단일 채널 모노펄스 시스템의 경우, 시스템 구성 변수의 변화를 통해 모노펄스 비율 곡선이 제어된다. 본 논문에서는 빔 조향 각도에 모노펄스 시스템 구성 변수를 적응형으로 제어하는데 참조할 수 있는 간소화된 수식을 제시하였다. 제시된 수식은 빔 조향 각도뿐만 아니라 방사 특성에 영향을 주는 위상배열안테나 설계 변수에 대응하여 균일한 모노펄스 비율 곡선을 유도할 수 있다.

• 방사선산업학회지
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• 제4권3호
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• pp.239-246
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• 2010

The aim of this study is selection of the male-sterile plant for inhibiting transgene flow through gamma-irradiation ($^{60}Co$) at the pollination and fertilization cycle of herbicide-tolerant genetically modified (GM) zoysiagrass (Zoysia japonica Steud.). High frequencies of plant mutations were obtained about 18% from $M_1$ generation at the doses (10 to 50 Gy). We also found that some $M_1$ plants showed male-sterile plants using de-husked seeds and comparison of stainable pollen using $KI-I_2$ solution. Besides the effects of irradiation on pollination and fertilization cycle, various other mutations like dwarf, cold tolerance, increasing grains and mass were observed. Four of dwarfism plants were selected through comparison of morphological characteristic between control and mutants during 4 years. These results demonstrated that the gamma-irradiation on pollination and fertilization cycle is very effective to induce the various mutations, and the male-sterile mutants are useful for controlling transgene flow and developing of high quality turfgasses.

• Biomolecules & Therapeutics
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• 제31권6호
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• pp.640-647
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• 2023

The skin, the largest organ in the body, undergoes age-related changes influenced by both intrinsic and extrinsic factors. The primary external factor is photoaging which causes hyperpigmentation, uneven skin surface, deep wrinkles, and markedly enlarged capillaries. In the human dermis, it decreases fibroblast function, resulting in a lack of collagen structure and also decreases keratinocyte function, which compromises the strength of the protective barrier. In this study, we found that treatment with γ-aminobutyric acid (GABA) had no toxicity to skin fibroblasts and GABA enhanced their migration ability, which can accelerate skin wound healing. UVB radiation was found to significantly induce the production of matrix metalloproteinase 1 (MMP-1), but treatment with GABA resulted in the inhibition of MMP-1 production. We also investigated the enhancement of filaggrin and aquaporin 3 in keratinocytes after treatment with GABA, showing that GABA can effectively improve skin moisturization. In vivo experiments showed that oral administration of GABA significantly improved skin wrinkles and epidermal thickness. After the intake of GABA, there was a significant decrease observed in the increase of skin thickness measured by calipers and erythema. Additionally, the decrease in skin moisture and elasticity in hairless mice exposed to UVB radiation was also significantly restored. Overall, this study demonstrates the potential of GABA as functional food material for improving skin aging and moisturizing.

• 전자공학회논문지D
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• 제36D권9호
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• pp.50-55
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• 1999

단일모드 광섬유의 한쪽 측면을 코어 가까이 연마한 광섬유와 그 위에 덮혀진 정합액 사이의 광결합을 이용한 가변 광 감쇠기를 제안하였다. 광섬유모드와 방사모드사이의 결합으로 인하여 정합액의 미세한 굴절률 변화는 큰 광손실의 변화를 발생시킨다. 정합액의 열광학 효과를 이용하여 광손실을 제어하였다. 실리콘 V홈을 이용하여 측면 연마된 광섬유 블록(block)을 제작하였다. 실험결과 $5^{\circ}C$ 정도의 온도변화로서 감쇠량을 최대와 최소사이에서 제어 할 수 있었다. 제작된 소자의 편광의존성 손실은 0.5 dB이었고, 삽입 손실은 0.2dB 이었다.

• 한국의학물리학회지:의학물리
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• 제5권2호
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• pp.35-43
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• 1994

전자파가 일상생활에서 생체에 많은 영향을 미치는 것으로 알려져 있으나 실제로 그 영향을 정성, 정량적으로 규명하는 것은 용이하지 않다. 본 연구에서는 생체의 전기적 신호를 이용하여 2.45GHz의 전자파에 노출시킨 토끼의 두부에 대한 영향을 측정하는 방법을 검토하였다. 연구결과, 두부모델의 손상정도는 뇌전위의 연속적인 FFT 신호처리에서 뇌활성도 저하를 관찰할 수 있었으며, 특정 주파수와 강도(최소허용전력과 치사전력)에 대한 기준 설정에 필요한 요소를 제시할 수 있었다.

• 대한후두음성언어의학회지
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• 제29권1호
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• pp.5-8
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• 2018

Patients who have the head and neck cancer are usually treated by surgery, radiation therapy, chemotherapy, or combinations of them. These treatments can induce variable degree of aspiration with dysphagia. The type and severity of aspiration depends on the size and location of the original tumor, the structures involved, and the treatment modality used for treatment. The management of aspiration after the head and neck cancer's treatment begins with an accurate evaluation for the cause and mechanism of aspiration through modified barium swallow (MBS) and fiberoptic endoscopic examination of swallowing (FEES). Then, the clinician can use postures, maneuvers, and exercises to treat the swallow disorder and to help the patient achieve optimal function. To achieve optimal swallowing without aspiration, multidimensional rehabilitation by various medical personnel is definitely necessary.

• 대한후두음성언어의학회지
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• 제29권1호
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• pp.9-13
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• 2018

Postoperative airway aspiration is not uncommon in patients with head and neck cancer. Airway aspiration has serious consequences, such as swallowing disorders, nutrition-related health problem, or reducing the quality of life due to maintenance of tracheal or nasogastric tubes. The postoperative oropharyngeal defect due to the surgery may interfere with normal swallowing reflex, or the laryngeal dysfunction caused by radiation therapy may cause severe airway aspiration, which may lead to complications such as dyspnea and pneumonia. Complete removal of the disease is also important in the treatment of head and neck cancer, but it is necessary to select a method to avoid and predict the occurrence of airway aspiration according to the treatment method. The most important factor to prevent airway aspiration after surgery is to preserve the proper volume of the oropharynx and to preserve at least one of the cricoarytenoid joint function. It is also the most effective way to reduce additional complications by seeking appropriate surgical treatment according to airway aspiration status. The purpose of this study is to review the operative methods that can induce airway aspiration and consider the prevention and treatment strategy through review of the literature.

• Archives of Pharmacal Research
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• 제29권12호
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• pp.1125-1131
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• 2006

This study was undertaken to elucidate the effect of diallyl disulfide (DADS), an oil-soluble organosulfur compound found in garlic, in suppressing human nasopharyngeal carcinoma cells. A potent increase (of at least 9-fold) in apoptotic cells has accompanied 1) a decrease in cell viability, 2) a increase of the fraction of S-phase cells by up to 63.8%, and 3) a transient increase of the phospho-p38 and phospho-p42/44 (phosphorylated p38 MAPK and phosphorylated p42/44 MAPK) in a time-and concentration-dependent manner. These results indicate that DADS can induce apoptosis in human nasopharyngeal carcinoma cells via, at least partly, S-phase block of the cell cycle, related to a rise in MAPK phosphorylation.