• Title/Summary/Keyword: Healthy volunteers

검색결과 860건 처리시간 0.249초

전이학습을 수행한 신경망을 사용한 압축센싱 심장 자기공명영상 (Compressed-Sensing Cardiac CINE MRI using Neural Network with Transfer Learning)

  • 박성재;윤종현;안창범
    • 전기전자학회논문지
    • /
    • 제23권4호
    • /
    • pp.1408-1414
    • /
    • 2019
  • 전이학습을 수행한 심층 인공신경망을 압축센싱 심혈관 자기공명영상에 적용하였다. 전이학습은 선행학습 신경망의 구조나 필터 커널, 가중치를 현재의 학습이나 응용에 활용하는 방법이다. 전이학습은 학습 속도를 향상시키고, 학습 데이터가 제한적일 때 신경망의 일반화에 도움이 된다. 8명의 건강한 지원자가 참여한 심장 자기공명영상 실험에서 전이학습을 수행한 신경망은 단독학습 신경망에 비해 학습시간이 5배 이상 단축되었다. 시험 데이터에 대해서도 전이학습을 수행한 신경망은 전이학습을 수행하지 않은 신경망에 비하여 낮은 정규화 평균제곱오차와 향상된 재구성 영상화질을 보였다.

Effect of Task Direction on the Maximal Pushing, Pulling, Twisting, and Grip Forces

  • Yoon, Jangwhon
    • 대한인간공학회지
    • /
    • 제35권5호
    • /
    • pp.413-423
    • /
    • 2016
  • Objective:The aims of this study are to understand the effects of task (pushing, pulling, and clockwise and counter clockwise twisting) direction on the maximal output and their grip forces and to explore the relationship between the maximal output and the grip forces. Background: Knowing the normative maximal grip force is not enough to design a good hand tool. The industrial designers should understand the required grip forces in various motions toward a specific direction to make an effective and efficient hand tool. Method: Eighteen healthy volunteers participated in the series of isometric maximal output force tests. A custom-made force measuring equipment collected the output and the grip forces for three seconds. Force measurements along the vertical, coronal and sagittal axes were randomly repeated three times. Results: The pulling was strongest and the pushing was weakest in all directions. The effect of motion on the output forces varied in different directions. The corresponding grip force increased in the order of pushing, pulling, clockwise twisting, and counter clockwise twisting in all directions. The maximal output and their grip forces were highly correlated but the relationship was affected by motion and direction. The regression coefficient was greatest in pulling and smallest in clockwise twisting. Conclusion: The effect of motion on the output forces varied in different directions. The maximal output and their grip forces were correlated but the relationship was affected by motion and direction. Application: Findings of this study can be valuable information for industrial designers to develop more productive hand tools and work stations to help preventing the musculoskeletal disorders at work.

Physiological Influence of Combined Mental Activity with Experimental Subway Noise

  • ;;최석철
    • 대한의생명과학회지
    • /
    • 제13권1호
    • /
    • pp.39-45
    • /
    • 2007
  • Numerous psychological stressors playa role in development of the cardiovascular disease. The aim of this study was to determine whether a combined mental activity with experimental subway noise affects hematological physiology. Fifty-four healthy volunteers were divided group I which underwent subway noise (n=24) and group II which underwent a combined mental activity with subway noise (n=30). Venous blood samples were collected for measuring CBC, prothrombine time (PT), activated partial thromboplastine time (APTT), erythrocyte sedimentation rate (ESR), D-dimer and high sensitive C-reactive protein (H-CRP) levels before, 50 min of stress task (S-50m) and 60 min of recovery (R-60m). Changed ratios of granulocyte, lymphocyte, monocyte and platelet counts at S-50m and R-60m were higher in group II compared to group I. RBC count and hematocrit level in group I increased whereas those in group II decreased at S-50m. PT, APTT and ESR in the both groups were shortened at R-60m and the decreased ratios were high in group II compared to group I. H-CRP and D-dimer in the both groups were elevated at S-50m and R-60m while the increased ratios in group II were greater than those in group I. These observations imply that a combined mental activity with experimental subway noise may be a stressor which affects hematological physiology.

  • PDF

Dot-Blot Immunoassay of Fasciola gigantica Infection using 27 kDa and Adult Worm Regurge Antigens in Egyptian Patients

  • Kamel, Hanan H.;Saad, Ghada A.;Sarhan, Rania M.
    • Parasites, Hosts and Diseases
    • /
    • 제51권2호
    • /
    • pp.177-182
    • /
    • 2013
  • The purpose of the present study was to evaluate the potential role of the 27-Kilodalton (KDa) antigen versus Fasciola gigantica adult worm regurge antigens in a DOT-Blot assay and to assess this assay as a practical tool for diagnosis fascioliasis in Egyptian patients. Fasciola gigantica antigen of an approximate molecular mass 27- (KDa) was obtained from adult worms by a simple elution SDS-PAGE. A Dot-Blot was developed comparatively to adult worm regurge antigens for the detection of specific antibodies from patients infected with F. gigantica in Egypt. Control sera were obtained from patients with other parasitic infections and healthy volunteers to assess the test and compare between the antigens. The sensitivity, specificity, positive and negative predictive values of Dot-Blot using the adult worm regurge were 80%, 90%, 94.1%, and 69.2% respectively, while those using 27-KDa were 100% which confirms the diagnostic potential of this antigen. All patients infected with Fasciola were positive, with cross reactivity reported with Schistosoma mansoni serum samples. This 27-KDa Dot-Blot assay showed to be a promising test which can be used for serodiagnosis of fascioliasis in Egyptian patients especially, those presenting with hepatic disease. It is specific, sensitive and easy to perform method for the rapid diagnosis particularly when more complex laboratory tests are unavailable.

Representation Techniques for 4-Dimensional MR Images

  • Homma, Kazuhiro;Takenaka, Kenji;Nakai, Yoshihiko;Hirose, Takeshi
    • 한국의학물리학회:학술대회논문집
    • /
    • 한국의학물리학회 2002년도 Proceedings
    • /
    • pp.429-431
    • /
    • 2002
  • Metabolic analysis of biological tissues, the interventional radiology in MRT (Magnetic Resonance Treatment) and for clinical diagnoses, representation of 4-Dimensional (4D) structural information (x,y,z,t) of biological tissues is required. This paper discusses image representation techniques for those 4D MR Images. We have proposed an image reconstruction method for ultra-fast 3D MRI. It is based on image interpolation and prediction of un-acquired pictorial data in both of the real and the k-space (the acquisition domain in MRI). A 4D MR image is reconstructed from only two 3D MR images and acquired a few echo signals that are optimized by prediction of the tissue motion. This prediction can be done by the phase of acquired echo signal is proportioned to the tissue motion. On the other hand, reconstructed 4D MR images are represented as a 3D-movie by using computer graphics techniques. Rendered tissue surfaces and/or ROIs are displayed on a CRT monitor. It is represented in an arbitrary plane and/or rendered surface with their motion. As examples of the proposed representation techniques, the finger and the lung motion of healthy volunteers are demonstrated.

  • PDF

Significance of Proliferation Markers and Prognostic Factors in Egyptian Patients with Multiple Myeloma

  • Abdelgawad, Iman A;Radwan, Noha H;Shafik, Roxan E;Shokralla, Hala A
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제17권3호
    • /
    • pp.1351-1355
    • /
    • 2016
  • Background: Multiple myeloma (MM) is influenced by genetic and micro-environmental changes. Malignant plasma cells produce an abnormal monoclonal immunoglobulin, as well as cytokines, such as IL-10 and IL-6 which stimulate cells of the bone marrow microenvironment (BMM) and cause dysfunction and failure of many organs. B cell activating factor (BAFF), IL6 and IL10 are known to influence the growth and survival of malignant clones. Aim: The objectives of the present study were to investigate the circulating levels of BAFF, IL-10 and IL-6, correlate them with well-known parameters of disease activity in patients with MM, and to detect their impact on patients' survival. Materials and Methods: This study was conducted on 89 newly diagnosed MM patients and seventy apparently healthy volunteers as a normal control group. BAFF, IL6, IL10 were measured by ELISA for both groups and survival analysis was performed for all patients. Results: Studied markers were higher in the MM patients compared to the normal control subjects. Patients survival was improved by high serum BAFF levels. Conclusions: High levels of BAFF were found to improve patients' survival. BAFF and IL-6 can be considered probable diagnostic markers for MM.

Detection and Prognostic Analysis of Serum Protein Expression in Esophageal Squamous Cell Cancer

  • Jiang, Hong;Wang, Xiao-Hong;Yu, Xin-Min;Zheng, Zhi-Guo
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제13권4호
    • /
    • pp.1579-1582
    • /
    • 2012
  • Objective: To assess differences in serum proteins in esophageal squamous cell carcinoma patients. Methods: 144 esophageal squamous cell carcinoma patients and 50 healthy volunteers were included in this study, with surface-enhanced laser desorption-ionization time-of-flight mass spectrometry and weak cation exchange magnetic beads. Follow-up allowed the relations between serum proteins and prognosis to be analyzed. Results: A total of 93 protein peaks were detected (molecular weight range: 1500-30000), 10 demonstrating statistically significant differences. There were no differences in protein peaks between 92 patients with a survival more than 2 years and 52 patients with survival less than 2 years. There were two significantly different protein peaks between 45 stage II patients with a survival more than 2 years and 14 stage II patients with survival less than 2 years. There was one significantly different protein peak between 22 stage III patients with a survival more than 2 years and 29 stage III patients with survival less than 2 years. Conclusion: Differences of serum proteins in esophageal squamous cell carcinoma are related to prognosis of patients. The protein fingerprint can be helpful for clinical diagnosis and treatment.

외관(外關) 자침이 Auditory P300에 미치는 영향 (Effect of Acupuncture at Oegwan(TE 5) on Auditory P300)

  • 김미선;박현철;유경;김락형
    • 동의신경정신과학회지
    • /
    • 제17권1호
    • /
    • pp.129-136
    • /
    • 2006
  • Objective : Audio-evoked potential is technique used for measuring brain functions such as memory, attention, and concentration. Although a number of studies on acupuncture for pain, there are few reports on the effect of acupuncture cognitive function. Methods : Fifteen healthy volunteers with no neurological condition took part of the study. $(23.27{\pm}2.09)$. In this study, we examined the changes in auditory P300 by acupuncture stimulation to 'Oegwan' on the left hand. Auditory P300 was recorded before, during and after acupuncture. The amplitude and latency of P300 at Fz, Cz, Pz point were calculated. Results : Auditory P300 amplitude decreased during and after acupuncture, but there was no statistical significance.(P< .05) Auditory P300 latency significantly decreased during and after acupuncture.(P< .05) Conclusions : The decrease of Auditory P300 latency time suggests that acupuncture at Oegwan has some effects on the cognitive function.

  • PDF

간세포 배양-약물대사를 위한 모델 연구 (I. Primary cultured hepatocytes as a key in vitro model to improve preclinical drug development)

  • 이경태
    • 한국응용약물학회:학술대회논문집
    • /
    • 한국응용약물학회 1994년도 제2회 추계심포지움
    • /
    • pp.135-140
    • /
    • 1994
  • Over past decades, numerous in vitro model has been developed to investigate drug metabolism. In the order of complexity we found the isolated perfused liver, hepatocytes in co-culture with epithelial cells, hepatocytes in suspension and in primary culture and subcellular hepatic microsomal fractions. Because they can be easily prepared from both animals (pharmacological and toxicological species) and humans (whole livers as well as biopsies obtained during surgery) hepatocytes in primary culture provide the most powerful model to better elucidate drug behavior at an early stage of preclinical development such as : 1. the characterization of main biotransformation reactions. 2. the identification of phase I and phase II isozymes involved in such reactions 3. the evaluation of interspecies differences allowing the selection of a second toxicological animal species more closely related to man on the basis of metabolic profiles 4. the detection of the inducing and/or inhibitory effects of a drug on metabolic enzymes, the prediction of drug interactions 5. the estimation of inter-individual variability in biotransformation reactions. The use of hepatocytes, and in particular those obstained from humans, at an early stage of drug development allows the obtention of more predictive preclinical data and a better knowledge of drug behavior in humans before the first administration of the drug in healthy volunteers.

  • PDF

정상보행시 체중심의 수직 가속도 특성 (Characteristics of Vertical Acceleration at Center of Mass of the Body in Normal Gait)

  • 이진복;강성재;김영호
    • 한국전문물리치료학회지
    • /
    • 제9권3호
    • /
    • pp.39-46
    • /
    • 2002
  • In this study, vertical acceleration of center of mass was observed along normal gait phases in 9 healthy male volunteers (aged $25.7{\pm}2.18$). The developed wireless accelerometric device was attached on the intervertebral space between L3 and L4 using a semi-elastic waist belt. A three-dimensional motion analysis system, synchronized with the accelerometry, was used for detecting gait phases. There was no significant correlation between the body weight and the acceleration. The first peak curve covered loading response phase. The second downward peak point was matched accurately with the opposite toe-off. In mid-stance and terminal stance, the acceleration curve highly resembled the vertical ground reaction force curve. There was no significant difference in timing between the final upward peak point and the initial contact. Therefore, the developed accelerometry system would be helpful in determining determine temporal gait pattems in patients with gait disorders.

  • PDF