• Safety and Health at Work
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• v.7 no.4
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• pp.317-321
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• 2016

Background: This study was conducted with aim of providing an overview of the current status of occupational health services and identifying the most common harmful agents at workplaces of Iranian self-employed enterprises (Nano-Scale Enterprises). Methods: A cross-sectional study was performed among a random sample including 1,758 employees engaging in self-employed enterprises with 5 and less employees. Results: Coverage of occupational health surveillance was very poor, annual health examinations were been conducted only for 64 (3.64%) of males and 31 (1.76%) of females, and occupational health trainings were not included of the services at all. Personal Protective Equipment were available in 462 (26.3%) of the enterprises. only in 0.4% of the enterprises working processes were been equipped by a local exhaust ventilation system. Difficult postures were the most common (81.5%) adverse working conditions. Conclusion: This study revealed a poor level of the implementation of occupational health services in Iranian self-employed enterprises. Based on the findings, providing basic training on the occupational health, more enforcing in conduction of health examinations and providing PPE, and taking appropriate strategies aimed at eliminating or minimizing work environment harmful agents are the major factor that should be considered to improve the level of occupational health services among the studied enterprises.

• Journal of Radiation Protection and Research
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• v.34 no.1
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• pp.25-30
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• 2009

Micro-columnar CsI(Tl) is the most popular scintillator material which is used for many indirect digital X-ray imaging detectors. The light scattering at the surface of micro-columnar CsI(Tl) scintillator was studied to find the correlation between the surface roughness and the resultant image resolution of indirect X-ray imaging detectors. Using a commercially available optical simulation program, Light Tools, MTF (Modulation Transfer Function) curves of the CsI(Tl) film thermally evaporated on glass substrate with different thickness were calculated and compared with the experimental estimation of MTF values by the edge X-ray image method and CCD camera. It was found that the standard deviation value of Gaussian scattering model which is determined by the surface roughness of micro-columns could certainly change the MTF value of image sensors. This model and calculation methodology will be beneficial to estimate the overall performance of indirect X-ray imaging system with CsI(Tl) scintillator film for optimum design depending on its application.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1966_1967
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• 2009

As an attempt to characterize the pulse behaviors at the three pulse diagnosis positions in the oriental medicine which are called Chon, Gwan, and Cheok, we measure the pluse waveforms by SphygmoCor apparatus, that has been used widely for the evaluation of the arterial stiffness, and examine the Augmentation Index (AIx) at the aorta. For the study, twenty healthy men at the age of twenties have participated as the subject group. The pulse has been measured twice at the three palpation positions, and by two-way repeated measures ANOVA we tested the repeatability and the mean differences in the aortic AIx between Chon, Gwan, and Cheok. The AIx was found to be statistically different between the measurement positions. Duncan's test shows that the AIx is statistically different between Chon and the other two positions. Our study may be used as a reference for further scientific quantification of the pulse diagnosis.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6549-6556
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• 2013

Leukemia stem cells (LSCs) play important roles in leukemia initiation, progression and relapse, and thus represent a critical target for therapeutic intervention. Hence, it is extremely urgent to explore new therapeutic strategies directly targeting LSCs for acute myelogenous leukemia (AML) therapy. We show here that Angelica sinensis polysaccharide (ASP), a major active component in Dong quai (Chinese Angelica sinensis), effectively inhibited human AML $CD34^+CD38^-$ cell proliferation in vitro culture in a dose-dependent manner while sparing normal hematopoietic stem and progenitor cells at physiologically achievable concentrations. Furthermore, ASP exerted cytotoxic effects on AML K562 cells, especially LSC-enriched $CD34^+CD38^-$ cells. Colony formation assays further showed that ASP significantly suppressed the formation of colonies derived from AML $CD34^+CD38^-$ cells but not those from normal $CD34^+CD38^-$ cells. Examination of the underlying mechanisms revealed that ASP induced $CD34^+CD38^-$ cell senescence, which was strongly associated with a series of characteristic events, including up-regulation of p53, p16, p21, and Rb genes and changes of related cell cycle regulation proteins P16, P21, cyclin E and CDK4, telomere end attrition as well as repression of telomerase activity. On the basis of these findings, we propose that ASP represents a potentially important agent for leukemia stem cell-targeted therapy.

• Toxicological Research
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• v.22 no.4
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• pp.333-338
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• 2006

This study was to investigate the preventive effects in anti-oxidation of Ulva lactuca extract fractions (ULEF) against $CCl_4$ toxification in liver total homogenate and mitochondrial fraction of ULEF-pretreated and carbon tetrachloride $(CCl_4)-posttreated$ rats. ULEF was intraperitoneally administered into rats at dose of 1 ml/kg for14 days. On the day 15, 3.3 ml/kg of $CCl_4$ dissolved in olive oil (1:1) was injected 12 hr before anesthetization. Activities of superoxide dismutase(SOD) in mitochondrial fraction were measured and catalase (CAT), glutathione peroxidase (GPx), malondialdehyde (MDA) in liver total homogenate. SOD, CAI and GPx were higher in the ULEF-pretreated and $CCl_4-posttreated$ group than those in the $CCl_4-posttreated$ group, and the pretreatment of ULEF decreased MDA. These results showed that the pretreatment of ULEF had the preventive role in the activities of anti-oxidative enzymes, SOD, CAT and GPx

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.5
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• pp.1249-1253
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• 2006

The fractions of Capsosiphon fulvescens were studied to verify the anticancer and immunostimulating activity. The fractions from the ethanol extract of C. fulvescens were prepared by the systematic extraction procedure with the solvents such as hexane, ethyl ether, methanol, butanol and H$_2$O. The cytotoxic effects of C. fulvescens fractions against human leukemia cell line U937, mouse neuroblastoma cell line (NB41A3), human hepatoma cell line (HepG2)and rat glioma cell line (C6) were investigated. Ethyl ether fraction of C. fulvescens showed the highest cytotoxicity against all four cell lines tested. In addition, H$_2$O fraction also showed relatively high cytotoxicity. Dose dependent patterns were observed on all four cell lines. The immune-stimulating effects of C. fulvescens fractions on rat macrophage cell line (RAW 264.7) were also investigated. All five fractions of C. fulvescens extract stimulated NO production with concentration dependant manner. These results suggest that C. fulvescens may be a useful candidate for a natural antitumor and immune-stimulating agent.

• Biomolecules & Therapeutics
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• v.25 no.2
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• pp.186-193
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• 2017

Tetrandrine (Tet), a bisbenzylisoquinoline alkaloid, has been reported to have a radiosensitization effect on tumors. However, its effects on human glioma and the specific molecular mechanisms of these effects remain unknown. In this study, we demonstrated that Tet has a radiosensitization effect on human glioma cells. It has been hypothesized that Tet has a radiosensitization effect on glioma cells by affecting the glioma cell cycle and DNA repair mechanism and that ERK mediates these activities. Therefore, we conducted detailed analyses of the effects of Tet on the cell cycle by performing flow cytometric analysis and on DNA repair by detecting the expression of phosphorylated H2AX by immunofluorescence. We used western blot analysis to investigate the role of ERK in the effect of Tet on the cell cycle and DNA repair. The results revealed that Tet exerts its radiosensitization effect on glioma cells by inhibiting proliferation and decreasing the expression of phosphorylated ERK and its downstream proteins. In summary, our data indicate that ERK is involved in Tet-induced radiosensitization of glioma cells via inhibition of glioma cell proliferation or of the cell cycle at G0/G1 phase.

• Journal of Internet Computing and Services
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• v.19 no.6
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• pp.31-40
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• 2018

With the development of IT technology recently, medical information systems are being constructed in an integrated u-health environment through cloud services, IoT technologies, and mobile applications. These kinds of medical information systems should provide the medical staff with authorities to access patients' medical information for emergency status treatments or therapeutic purposes. Therefore, in the medical information systems, the reliable and prompt authentication processes are necessary to access the biometric information and the medical information of the patients in charge of the medical staff. However, medical information systems are accessing with simple and static user authentication mechanism using only medical ID / PWD in the present system environment. For this reason, in this paper, we suggest a dynamic situation authentication mechanism that provides transparency of medical information access including various authentication factors considering patient's emergency status condition and dynamic situation authentication system supporting it. Our dynamic Situation Authentication is a combination of user authentication and mobile device authentication, which includes various authentication factor attributes such as emergency status, role of medical staff, their working hours, and their working positions and so forth. We designed and implemented a dynamic situation authentication system including emergency status decision, dynamic situation authentication, and authentication support DB construction. Finally, in order to verify the serviceability of the suggested dynamic situation authentication system, the medical staffs download the mobile application from the medical information server to the medical staff's own mobile device together with the dynamic situation authentication process and the permission to access medical information to the patient and showed access to medical information.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.11 no.4
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• pp.299-306
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• 2017

The Korean medical device industry has increased dramatically due to various investments in the domestic medical device industry and the introduction of new technologies, but the domestic medical device usage rate in great hospital is still low. In this paper, improvement point for domestic medical device was suggested by domestic medical device usage rate and user and manager's perception survey in great hospitals in Korea. To do this, a survey on the types of medical devices and domestic medical device usage rates were conducted at four national university hospitals in Korea. From this results, the priority survey medical devices were selected. Improvements of Korean medical devices were suggested by failure mode analysis and user awareness surveys for the priority survey medical devices.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.159-159
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• 2003