• Title/Summary/Keyword: resonance evaluation

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Differences in Ability to Predict the Success of Motor Action According to Dance Expertise - Focusing on Pirouette En Dehors (무용 숙련성에 따른 동작결과예측 능력의 차이: 삐루엣 앙 디올 동작을 중심으로)

  • Han, Siwan;Ryu, Je-Kwang;Yi, Woojong;Yang, Jonghyun
    • Korean Journal of Cognitive Science
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    • v.29 no.2
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    • pp.121-135
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    • 2018
  • Dancers' motions are perceived by observers through visual processes with visual information forming the basis for the observers' appreciation and evaluation of the dancers' motions. There have been many discussions as to whether or not observers' personal athletic capabilities form an essential basis for accurate assessment of the motions of others but, so far, no valid conclusions have been reached. The purpose of this study is to investigate how the ability to predict motions of others varies depending on the athletic expertise of the observers. Participants of this research were ballet dancers of varying athletic expertise. Twenty seven participants were divided into three groups with nine in each: beginners, intermediate experts and experts. The participants watched the same dance video and then evaluated whether the motion would be successful or not. The movement related visual information required to evaluate the success of the motion was systematically adjusted by controlling the length of the video. Using the temporal occlusion method, this study measured the response accuracy of the participants by category of expertise. Under the circumstance with insufficient visual information to utilize, the experts showed higher rates of correct response than the intermediate experts and the beginners. The beginners showed higher rates of wrong response than the experts and the intermediate experts. These results showed that the ability to predict success or failure of a dance motion varied depending on motion expertise of the observers, although they had similar level of expertise in perception. Participants considered to have high athletic expertise showed high prediction ability on the result of the motion. In addition, high expertise in perception reduced the likelihood that participants would make hasty responses under the circumstance with insufficient information and helped to reduce wrong response rate. In conclusion, this study showed that motor expertise and perceptual expertise contribute to prediction accuracy of observed motions.

Retrospective Evaluation of Discrepancies between Radiological and Pathological Size of Hepatocellular Carcinoma Masses

  • Tian, Fei;Wu, Jian-Xiong;Rong, Wei-Qi;Wang, Li-Ming;Wu, Fan;Yu, Wei-Bo;An, Song-Lin;Liu, Fa-Qiang;Feng, Li;Liu, Yun-He
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.21
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    • pp.9487-9494
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    • 2014
  • Background: The size of a hepatic neoplasm is critical for staging, prognosis and selection of appropriate treatment. Our study aimed to compare the radiological size of solid hepatocellular carcinoma (HCC) masses on magnetic resonance imaging (MRI) with the pathological size in a Chinese population, and to elucidate discrepancies. Materials and Methods: A total of 178 consecutive patients diagnosed with HCC who underwent curative hepatic resection after enhanced MRI between July 2010 and October 2013 were retrospectively identified and analyzed. Pathological data of the whole removed tumors wereassessed and differences between radiological and pathological tumor size were identified. All patients were restaged using a modified Tumor-Node-Metastasis (TNM) staging system postoperatively according to the maximum diameter alteration. The lesions were classified as hypo-staged, iso-staged or hyper-staged for qualitative assessment. In the quantitative analysis, the relative pre and postoperative tumor size contrast ratio ($%{\Delta}size$) was also computed according to size intervals. In addition, the relationship between radiological and pathological tumor diameter variation and histologic grade was analyzed. Results: Pathological examination showed 85 (47.8%) patients were overestimated, 82 (46.1%) patients underestimated, while accurate measurement by MRI was found in 11 (6.2%) patients. Among the total subjects, 14 (7.9%) patients were hypo-staged and 15 (8.4%) were hyper-staged post-operatively. Accuracy of MRI for calculation and characterized staging was related to the lesion size, ranging from 83.1% to 87.4% (<2cm to ${\geq}5cm$, p=0.328) and from 62.5% to 89.1% (cT1 to cT4, p=0.006), respectively. Overall, MRI misjudged pathological size by 6.0 mm (p=0.588 ), and the greatest difference was observed in tumors <2cm (3.6 mm, $%{\Delta}size=16.9%$, p=0.028). No statistically significant difference was observed for moderately differentiated HCC (5.5mm, p=0.781). However, for well differentiated and poorly differentiated cases, radiographic tumor maximum diameter was significantly larger than the pathological maximum diameter by 3.15 mm and underestimated by 4.51 mm, respectively (p=0.034 and 0.020). Conclusions: A preoperative HCC tumor size measurement using MRI can provide relatively acceptable accuracy but may give rise to discrepancy in tumors in a certain size range or histologic grade. In pathological well differentiated subjects, the pathological tumor size was significantly overestimated, but underestimated in poorly differentiated HCC. The difference between radiological and pathological tumor size was greatest for tumors <2 cm. For some HCC patients, the size difference may have implications for the decision of resection, transplantation, ablation, or arterially directed therapy, and should be considered in staging or selecting the appropriate treatment tactics.

The usefulness of diagnostic tests in children with language delay (언어 발달지연 환아에서 진단적 검사의 유용성)

  • Oh, Seung Taek;Lee, Eun Sil;Moon, Han Ku
    • Clinical and Experimental Pediatrics
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    • v.52 no.3
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    • pp.289-294
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    • 2009
  • Purpose : To assess the usefulness of magnetic resonance imaging (MRI), karyotyping, brainstem auditory evoked potential (BAEP), electroencephalogram (EEG), tandem mass screening test, and newborn metabolic screening test in children with language delay for diagnosing underlying diseases. Methods : From January 2000 to June 2007, a retrospective chart review was performed for 122 children with language delay who visited the Child Neurology Clinic at Yeungnam University Hospital and who underwent neuropsychologic tests and other diagnostic evaluations for underlying diseases. They were grouped into phenomenological diagnostic categories, and test results were analyzed according to the underlying diseases. Results : Of 122 patients, 47 (38.5%) had mental retardation, 40 (32.8%) had developmental language disorders, 23 (18.9 %) had borderline IQ, and 12 (9.8%) had autism spectrum disorder. In 26 (21.3%) cases, the causes or relevant clinical findings to explain language delay were found. Eight (10.4%) of 77 MRIs, 6 (8.0%) of 75 EEGs, and 4 (5%) of 80 BAEPs showed abnormal results. Results directly attributed to diagnosing underlying diseases were 2 hearing defects in BAEPs and 1 bilateral perisylvian cortical dysplasia in MRIs. No abnormal results were found in karyotyping, tandem mass screening tests, and new-born screening tests. Conclusion : Commonly used tests to diagnose the cause of language delay are not very effective and should only be used selectively, according to patient characteristics. However, despite the low diagnostic yields from these tests, because many patients show abnormal results, these tests are useful when conducted in complete evaluation.

Evaluation of Present Curriculum for Devlopment of Dept. of Radiological Science Curriculum (방사선학과 교육과정 개선을 위한 현 교육과정 평가)

  • Kang, Se-Sik;Kim, Chang-Soo;Choi, Seok-Yoon;Ko, Seong-Jin;Kim, Jung-Hoon
    • The Journal of the Korea Contents Association
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    • v.11 no.5
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    • pp.242-251
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    • 2011
  • A curriculum of study demands a change as period of time and society evolve. Therefore, at this point where changes are required, this study is to analyze and evaluate the curriculums which will enhance and improve current studies as a preceding stage. The research was based on the survey by groups of education experts and 19 universities with current curriculum of study in radiologic science, and their references. The study was focused on the scope of work by radiologic technologist, change of college systems, academic research about radiologic science, and the improvement and the future of radiologic science field in perspective to globalization and the digital era. In terms of work scope, angiography and interventional radiology at 6 to 8 schools, fluoroscopy at 4 schools, ultrasound and practices at 6 schools, magnetic resonance image at 2 schools were found to be unestablished. The basic medical subjects, humuan physiology, human anatomy and practices, medical terminology courses were set up at most schools; however, pathology at 5 schools, image anatomy at 6 schools, clinical medicine at 11 schools were yet opened. Among the basic science and engineering subjects, general biology and its practices at 11 schools, general physics and its practices at 14 schools, and general chemistry and its practices at 8 schools were established which is about a half from a total number of schools. Only 4-5 schools established digital subjects such as, health computer, computer programming, PACS which are the basic major subjects. In order to provide academic improvement in radiologic science, digitalized education and globalization, and basis for future-oriented education for the field of radiologic science, including expanded scope of work, it is acknowledged that curriculums that are opened and run at each school need to be standardized. Therefore, the need for introduction of certificate for the radiologic science education courses are suggested.

Evaluation of Metabolic Abnormality in Brain Tumors by In Viuo $^1$H MR Spectroscopy at 3 Tesla (3T 양성자 자기공명분광에 의한 뇌종양의 대사물질 이상소견)

  • Choe, Bo-Young;Jeun, Sin-Soo;Kim, Bum-Soo;Lee, Jae-Mun;Chung, Sung-Taek;Ahn, Chang-Beom;Oh, Chang-Hyun;Kim, Sun I.;Lee, Hyoung-Koo
    • Progress in Medical Physics
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    • v.13 no.3
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    • pp.120-128
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    • 2002
  • To investigate differences between the metabolic ratios of normal controls and brain tumors such as astrocytomas and glioblastoma multiforme (GM) by proton MR spectroscopy (MRS) at 37 high field system. Using 3T MRI/MRS system, localized water-suppressed single-voxel technique in patients with brain tumors was employed to evaluate spectra with peaks of N-acetyl aspartate (NAA), choline-containing compounds (Cho), creatine/phosphocreatine (Cr) and lactate. On the basis of Cr, these peak areas were quantificated as a relative ratio. The variation of metabolites measurements of the designated region in 10 normal volunteers was less than 10%. Normal ranges of NAA/Cr and Cho/Cr ratios were 1.67$\pm$018 and 1.16$\pm$0.15, respectively. NAA/Cr ratio of all tumor tissues was significantly lower than that of the normal tissues (P=0.005). Cho/Cr ratio of glioblastoma multiforme was significantly higher than that of astrocytomas (P=0.001). Lactate was observed in all tumor cases. The present study demonstrated that the neuronal degradation or loss was observed in all tumor tissues. Higher grade of brain tumors was correlated with higher Cho/Cr ratio, indicating a significant dependence of Cho levels on malignancy of gliomas. This results suggest that clinical proton MR spectroscopy could be useful to predict tumor malignancy.

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BONE DENSITY AND HISTOMORPHOMETRY ASSESSMENT OF DENTAL IMPLANT USING COMPUTERIZED TOMOGRAPHY (컴퓨터 영상을 이용한 임플란트 식립부위의 골밀도와 조직학적 연구)

  • Son, Jang-Ho;Choi, Byung-Hwan;Park, Soo-Won;Cho, Yeong-Cheol;Sung, Iel-Yong;Lee, Ji-Ho;Byun, Ki-Jung
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.31 no.2
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    • pp.136-142
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    • 2009
  • Bone density in the recipient implant site seems to be an important factor for long term success of endosseous implants. Preoperative evaluation of bone density is very helpful to assist the clinician with the treatment planning of implant therapy. Accurate information on bone density will help the surgeon identify suitable implant sites, thereby improving the success rate of the procedure. Purpose; The aim of this study was to evaluate a correlation between bone density measured preoperatively with computerized tomography and histologically measured bone density by bone biopsy. Patients and methods; Twenty seven patients were selected. All the patients were in good health, with no systemic disorder and additional bone graft. Preoperatively the patients underwent CT scanning to evaluate Houmsfield Unit(HU). Each patients wore a surgical template for implant placement. During surgery 2mm in diameter and 6mm in length specimens were taken. Histomorphometric analysis was performed using digitalized image analysis software Axiovision 4.3. Also, the Resonance frequency analysis(RFA) and insertion torque values were recorded. Results; The highest histomorphometric values was found in the posterior mandible $32.3{\pm}3.8$, followed by $29.9{\pm}2.6$ for the posterior maxilla, $29.4{\pm}2.6$ for the anterior maxilla, $28.6{\pm}2.3$ for the anterior mandible(p=0.214). The hounsfield unit was $989.2{\pm}258.1$ in the posterior mandible, $845.0{\pm}241.5$ in the anterior maxilla, $744.5{\pm}92.6$ in the anterior mandible, $697.3{\pm}136.9$ in the posterior maxilla(p=0.045). This results may suggest that there are strong correlation between the histomorphometric values and hounsfield unit(r=0.760, p<0.05). The RF measurements were $81.9{\pm}2.4$ ISQ in the posterior mandible, $79.0{\pm}1.4$ ISQ in the anterior mandible, $78.3{\pm}4.6$ ISQ in the posterior maxilla, $76.5{\pm}5.0$ ISQ in the anterior maxilla(p=0.048). The insertion torque values was $43.2{\pm}4.2\;Ncm$ in the posterior mandible, $42.0{\pm}0.0\;Ncm$ in the anterior mandible, $41.3{\pm}4.1\;Ncm$ in the posterior maxilla, $40.8{\pm}3.8\;Ncm$ in the anterior maxilla(p=0.612). This results may suggest that there are statistical significance between the hounsfield unit and the insertion torque values(r=0.494, p<0.05), the histomorphometric values and the insertion torque values(r=0.689, p<0.05). But there was no correlation between histomorphometric values and ISQ. There was no statistical significance in age and gender effect on parameters. Conclusions; There was significant correlations between bone density and implant stability parameters. The bone density measurements using preoperative CT may help clinicians to predict primary stability before implant insertion, which is associated with implant survival rates.

Recent Progress in Air Conditioning and Refrigeration Research - A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2004 and 2005 - (공기조화, 냉동 분야의 최근 연구 동향 -2004년 및 2005년 학회지 논문에 대한 종합적 고찰-)

  • Choi, Yong-Don;Kang, Yong-Tae;Kim, Nae-Hyun;Kim, Man-Hoe;Park, Kyoung-Kuhn;Park, Byung-Yoon;Park, Jin-Chul;Hong, Hi-Ki
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.19 no.1
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    • pp.94-131
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    • 2007
  • A review on the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering in 2004 and 2005 has been done. Focus has been put on current status of research in the aspect of heating, cooling, air-conditioning, ventilation, sanitation and building environment. The conclusions are as follows. (1) Most of fundamental studies on fluid flow were related with heat transportation of facilities. Drop formation and rivulet flow on solid surfaces were interesting topics related with condensation augmentation. Research on micro environment considering flow, heat, humidity was also interesting for comfortable living environment. It can be extended considering biological aspects. Development of fans and blowers of high performance and low noise were continuing topics. Well developed CFD and flow visualization(PIV, PTV and LDV methods) technologies were widely applied for developing facilities and their systems. (2) The research trends of the previous two yews are surveyed as groups of natural convection, forced convection, electronic cooling, heat transfer enhancement, frosting and defrosting, thermal properties, etc. New research topics introduced include natural convection heat transfer enhancement using nanofluid, supercritical cooling performance or oil miscibility of $CO_2$, enthalpy heat exchanger for heat recovery, heat transfer enhancement in a plate heat exchanger using fluid resonance. (3) The literature for the last two years($2004{\sim}2005$) is reviewed in the areas of heat pump, ice and water storage, cycle analysis and reused energy including geothermal, solar and unused energy). The research on cycle analysis and experiments for $CO_2$ was extensively carried out to replace the Ozone depleting and global warming refrigerants such as HFC and HCFC refrigerants. From the year of 2005, the Gas Engine Heat Pump(GHP) has been paid attention from the viewpoint of the gas cooling application. The heat pipe was focused on the performance improvement by the parametric analysis and the heat recovery applications. The storage systems were studied on the performance enhancement of the storage tank and cost analysis for heating and cooling applications. In the area of unused energy, the hybrid systems were extensively introduced and the life cycle cost analysis(LCCA) for the unused energy systems was also intensively carried out. (4) Recent studies of various refrigeration and air-conditioning systems have focused on the system performance and efficiency enhancement. Heat transfer characteristics during evaporation and condensation are investigated for several tube shapes and of alternative refrigerants including carbon dioxide. Efficiency of various compressors and expansion devices are also dealt with for better modeling and, in particular, performance improvement. Thermoelectric module and cooling systems are analyzed theoretically and experimentally. (5) According to the review of recent studies on ventilation systems, an appropriate ventilation systems including machenical and natural are required to satisfied the level of IAQ. Also, an recent studies on air-conditioning and absorption refrigeration systems, it has mainly focused on distribution and dehumidification of indoor air to improve the performance were carried out. (6) Based on a review of recent studies on indoor environment and building service systems, it is noticed that research issues have mainly focused on optimal thermal comfort, improvement of indoor air Quality and many innovative systems such as air-barrier type perimeter-less system with UFAC, radiant floor heating and cooling system and etc. New approaches are highlighted for improving indoor environmental condition as well as minimizing energy consumption, various activities of building control and operation strategy and energy performance analysis for economic evaluation.

Usefulness of Acoustic Noise Reduction in Brain MRI Using Quiet-T2 (뇌 자기공명영상에서 Quiet-T2 기법을 이용한 소음감소의 유용성)

  • Lee, SeJy;Kim, Young-Keun
    • Journal of radiological science and technology
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    • v.39 no.1
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    • pp.51-57
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    • 2016
  • Acoustic noise during magnetic resonance imaging (MRI) is the main source for patient discomfort. we report our preliminary experience with this technique in neuroimaging with regard to subjective and objective noise levels and image quality. 60 patients(29 males, 31 females, average age of 60.1) underwent routine brain MRI with 3.0 Tesla (MAGNETOM Tim Trio; Siemens, Germany) system and 12-channel head coil. Q-$T_2$ and $T_2$ sequence were performed. Measurement of sound pressure levels (SPL) and heart rate on Q-$T_2$ and $T_2$ was performed respectively. Quantitative analysis was carried out by measuring the SNR, CNR, and SIR values of Q-$T_2$, $T_2$ and a statistical analysis was performed using independent sample T-test. Qualitative analysis was evaluated by the eyes for the overall quality image of Q-$T_2$ and $T_2$. A 5-point evaluation scale was used, including excellent(5), good(4), fair(3), poor(2), and unacceptable(1). The average noise and peak noise decreased by $15dB_A$ and $10dB_A$ on $T_2$ and Q-$T_2$ test. Also, the average value of heartbeat rate was lower in Q-$T_2$ for 120 seconds in each test, but there was no statistical significance. The quantitative analysis showed that there was no significant difference between CNR and SIR, and there was a significant difference (p<0.05) as SNR had a lower average value on Q-$T_2$. According to the qualitative analysis, the overall quality image of 59 case $T_2$ and Q-$T_2$ was evaluated as excellent at 5 points, and 1 case was evaluated as good at 4 points due to a motion artifact. Q-$T_2$ is a promising technique for acoustic noise reduction and improved patient comfort.

Multimodal Diagnostic Approach for Synovitis of the Wrist (수근관절 활액막염 원인 질환 진단을 위한 다중적 접근법)

  • Bae, Kee Jeong;Kim, Jihyeung;Yoon, Chan;Hong, Seong Hwa;Gong, Hyun Sik;Baek, Goo Hyun
    • Journal of the Korean Orthopaedic Association
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    • v.53 no.6
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    • pp.540-546
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    • 2018
  • Purpose: The purpose of this study was to suggest a multimodal diagnostic approach to determine the cause of the disease in patients diagnosed with synovitis of the wrist and who underwent synovectomy. Materials and Methods: Twenty-nine patients, who underwent contrast magnetic resonance imaging (MRI) preoperatively and synovectomy from January 2000 to December 2013, were reviewed retrospectively. Among them, 17 patients underwent a $Tc^{99m}$ white blood cell (WBC) scan preoperatively. In patients who met the diagnostic criteria of rheumatoid arthritis (RA), the diagnosis was confirmed as RA if the MRI finding or histology was compatible with RA. If the MRI finding and histology were disparate, the final diagnosis was made based on the histologic finding. Results: Of the nine patients who met the diagnostic criteria of RA, seven patients were finally diagnosed as RA and two patients as tuberculous arthritis. Of the 20 patients who did not meet the diagnostic criteria of RA, the MRI findings and histology were consistent with the same disease in 12 patients. In the remaining eight patients, five were diagnosed with nonspecific chronic synovitis, one with RA, and two with tuberculous arthritis based on the clinical findings, MRI, and histology findings. Conclusion: MRI and a WBC scan are very useful imaging modalities for diagnosing the causative condition of the wrist synovitis. A histology evaluation after synovectomy can also be useful in cases with a difficult diagnosis or are refractory to medications.

Two new triterpenoid saponins derived from the leaves of Panax ginseng and their antiinflammatory activity

  • Li, Fu;Cao, Yufeng;Luo, Yanyan;Liu, Tingwu;Yan, Guilong;Chen, Liang;Ji, Lilian;Wang, Lun;Chen, Bin;Yaseen, Aftab;Khan, Ashfaq A.;Zhang, Guolin;Jiang, Yunyao;Liu, Jianxun;Wang, Gongcheng;Wang, Ming-Kui;Hu, Weicheng
    • Journal of Ginseng Research
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    • v.43 no.4
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    • pp.600-605
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    • 2019
  • Background: The leaves and roots of Panax ginseng are rich in ginsenosides. However, the chemical compositions of the leaves and roots of P. ginseng differ, resulting in different medicinal functions. In recent years, the aerial parts of members of the Panax genus have received great attention from natural product chemists as producers of bioactive ginsenosides. The aim of this study was the isolation and structural elucidation of novel, minor ginsenosides in the leaves of P. ginseng and evaluation of their antiinflammatory activity in vitro. Methods: Various chromatographic techniques were applied to obtain pure individual compounds, and their structures were determined by nuclear magnetic resonance and high-resolution mass spectrometry, as well as chemical methods. The antiinflammatory effect of the new compounds was evaluated on lipopolysaccharide-stimulated RAW 264.7 cells. Results and conclusions: Two novel, minor triterpenoid saponins, ginsenoside $LS_1$ (1) and 5,6-didehydroginsenoside $Rg_3$ (2), were isolated from the leaves of P. ginseng. The isolated compounds 1 and 2 were assayed for their inhibitory effect on nitric oxide production in LPS-stimulated RAW 264.7 cells, and Compound 2 showed a significant inhibitory effect with $IC_{50}$ of $37.38{\mu}M$ compared with that of NG-monomethyl-L-arginine ($IC_{50}=90.76{\mu}M$). Moreover, Compound 2 significantly decreased secretion of cytokines such as prostaglandin $E_2$ and tumor necrosis factor-${\alpha}$. In addition, Compound 2 significantly suppressed protein expression of inducible nitric oxide synthase and cyclooxygenase-2. These results suggested that Compound 2 could be used as a valuable candidate for medicinal use or functional food, and the mechanism is warranted for further exploration.