• Title/Summary/Keyword: VP2

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Robust Optimization of the Solenoid Assembly in Electromagnetic Limited Slip Differential by Considering the Uncertainties in Machining Variables (가공변수의 불확실성을 고려한 전자제어식 차동제한장치 솔레노이드 어셈블리의 강건 최적설계)

  • Oh, Sang-Kyun;Lee, Kwang-Ki;Suh, Chang-Hee;Jung, Yun-Chul;Kim, Young-Suk
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.35 no.10
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    • pp.1307-1313
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    • 2011
  • The mechanical limited slip differential (LSD) in vehicles is being replaced by the electromagnetic LSD because of its fast response and better active control characteristics. The coil housing made of STS 304 is one of the most important parts in the solenoid assembly of the electromagnetic LSD. High geometrical accuracy is a prerequisite for the manufacture of such coil housings, but precision machining is difficult because of the use of STS 304 thin plate and the variance in machining variables. The aim of this study is to optimize the mean and variance of the shape accuracy in the coil housing by finding a robust solution for the machining process conditions. The mean and standard deviation of the jaw contact pressure, cutting speed, and feed rate are considered to be the major parameters for minimizing the geometrical mean and variance. The response surface model based on the second-order Taylor series is combined together to minimize the mean and variance of the shape accuracy of the coil housing.

Usefulness Evaluation of HRCT using Reconstruction in Chest CT (흉부CT 검사 시 HRCT 영상 재구성의 유용성)

  • Park, Sung-Min;Kim, Keung-Sik;Kang, Seong-Min;Yoo, Beong-Gyu;Lee, Ki-Bae
    • Korean Journal of Digital Imaging in Medicine
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    • v.17 no.1
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    • pp.13-18
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    • 2015
  • Purpose : Skip the repetitive HRCT axial scan in order to reduce the exposure of patients during chest HRCT scan, Helical Scan Data into a reconstructed image, and exposure of the patient change and visually evaluate the usefulness of the HRCT images. Materials and method : Patients were enrolled in the survey are 50 people who underwent chest CT scans of patients who presented to the hospital from January 2015 to March 2015. 50 people surveyed 22 people men and 28 people women people showed an average distribution of 30 to 80 years age was 48 years. 50 patients to Somatom Sensation 64 ch (Siemens) model with 120 kVp tube voltage to a reference mAs tube current to mAs (Care dose, Siemens) as a whole, including the lungs and the chest CT scan was performed. Scan upon each patient CARE dose 4D (Automatic exposure control, Siemens Medical Solution Erlangen, Germany) was to maintain the proper radiation dose scan every cross-section through a device that automatically adjusts the tube current of. CT scan is the rotation time of the Tube slice collimation, slice width 0.6 mm, pitch factor was made under the terms of 1.4. CT scan obtained after the raw data (raw data) to the upper surface of the axial images and coronal images for each slice thickness 1 mm, 5 mm intervals in the high spatial frequency calculation method (hight spatial resolution algorithm, B60 sharp) was the use of the lung window center -500 HU, windows were reconstructed into images in the interval -1000 HU to see. Result : 1. Measure the total value of DLP 50 patients who proceed to chest CT group A (Helical Scan after scan performed with HRCT) and group B (Helical Scan after the HR image reconstruction to the original data) compared with the group divided, analysis As a result of the age, but show little difference for each age group it had a decreased average dose of about 9%. 2. A Radiation read the results of the two Radiologist and a doctor upper lobe and middle lobe of the lung takes effect the visual evaluation is not a big difference between the two images both, depending on the age of the patient, especially if the blood vessels of the lower lobe (A: 3.4, B: 4.6) and bronchi(A: 3.8, B4.7) image shake caused by breathing in anxiety (blurring lead) to the original data (raw data) showed that the reconstructed image is been more useful in diagnostic terms. Conclusion : Scan was confirmed a continuous, rapid motion video to get Helical scan is much lower lobe lung reduction in visual blurring, Helical scan data to not repeat the examination by obtaining HRCT images reorganization reduced the exposure of the patient.

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Studies on the Antitumor Activity of Gamisoam-san via Suppressing Angiogenesis and Growth Factor Expression (혈관신생 및 이식암세포증식 억제를 통한 가미소암산의 항암작용연구)

  • Yoon Sung Chan;Ahn Seong Hun;Mun Yean Ja;Kim Jin Kyeong;Choo Young Kug;Jung Kyu Yong;Kim Yeong Mok;Woo Won Hong
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.4
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    • pp.969-979
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    • 2003
  • Gamisoamsan is a prescription originated in Soamsan which is known as an anti-cancer remedy in the traditional Korean Medicine. To enhance the synergic effects of anti-cancer activity of Soamsan, this study reconstituted the original components of Soamsan with a slight modification and produced a novel herbal remedy, namely Gamisoamsan. To investigate the effects of Gamisoamsan on anti-cancer reaction, I studied the effects of Gamisoamsan on angiogenesis via chorioallantoic membrane (CAM) assay, corneal neovascularization assay and the effects on expression of growth factor which are VEGF, TGF-β, bFGF and IMUP-1. Anti-cancer effects of Gamisoamsan was also abserved through hematological parameters, tumor volume and survival rate in mice. Gamisoamsan inhibited embryonic angiogenesis of blood vessels in CAM assay and inhibited neovascularization of ral cornea. Gamisoamsan reduced cell proliferation in HT1080 cells and IC50 was 2.18 ㎎/㎖ Gamisoamsan reduced the expression of VEGF, TGF-β, bFGF and IMUP-1 which was known as vascular growth factor and this effects of Gamisoamsan was predominant than VP-16. The treatment of Gamisoamsan decreased the CT-26 cell inoculated-tumor volume in mice colon adenocarcinoma and increased mice survival which was inoculated CT-26 cells. The results of the present study suggest that Gamisoamsan extracts has a potential anti-tumor activity and may be an useful remedy to prevent and/or treat cancer.

Molecular epidemiology of Aleutian mink disease virus causing outbreaks in mink farms from Southwestern Europe: a retrospective study from 2012 to 2019

  • Prieto, Alberto;Fernandez-Antonio, Ricardo;Lopez-Lorenzo, Gonzalo;Diaz-Cao, Jose Manuel;Lopez-Novo, Cynthia;Remesar, Susana;Panadero, Rosario;Diaz, Pablo;Morrondo, Patrocinio;Diez-Banos, Pablo;Fernandez, Gonzalo
    • Journal of Veterinary Science
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    • v.21 no.4
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    • pp.65.1-65.13
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    • 2020
  • Background: Aleutian mink disease virus (AMDV) causes major economic losses in fur-bearing animal production. The control of most AMDV outbreaks is complex due to the difficulties of establishing the source of infection based only on the available on-farm epidemiological data. In this sense, phylogenetic analysis of the strains present in a farm may help elucidate the origin of the infection and improve the control and biosecurity measures. Objectives: This study had the following aims: characterize the AMDV strains from most outbreaks produced at Spanish farms between 2012-2019 at the molecular level, and assess the utility of the combined use of molecular and epidemiological data to track the possible routes of infection. Methods: Thirty-seven strains from 17 farms were partially sequenced for the NS1 and VP2 genes and analyzed phylogenetically with other strains described worldwide. Results: Spanish AMDV strains are clustered in four major clades that generally show a good geographical correlation, confirming that most had been established in Spain a long time ago. The combined study of phylogenetic results and epidemiological information of each farm suggests that most of the AMDV outbreaks since 2012 had been produced by within-farm reservoirs, while a few of them may have been due to the introduction of the virus through international trade. Conclusions: The combination of phylogenetic inference, together with epidemiological data, helps assess the possible origin of AMDV infections in mink farms and improving the control and prevention of this disease.

The Study of Appropriate X-ray Tube Angle for the Anterior-posterior Chest Radiography Using S-align Function (S-align 기능을 이용한 흉부 전·후 방향 검사 시 적절한 X선관 각도에 관한 연구)

  • Park, Myeong-Ju;Joo, Young-Cheol;Kim, Min-Suk;Yuk, Jeong-Won;Kim, Han-Yong;Kim, Dong-Hwan
    • Journal of radiological science and technology
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    • v.45 no.4
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    • pp.299-304
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    • 2022
  • This study uses the 'S-align' function to present a reference value of the X-ray tube angle for the realization of an image similar to that of the chest PA image during chest AP radiography. This study targeted dummy phantom and used a 17"×17" DR image receptor. The irradiation conditions were 110 kVp, 160 mA, 50 ms, and the distance between the central X-ray and the image receptor was set to 180 cm and 110 cm, respectively. The end of the catheter was placed at the 11th thoracic height to indicate the nasogastric tube. In the case of lung apex length measurement, the mean value of measurement was 30.53±0.47 in PA. T 0°, TCA 5~25°, TCE 5~15° were 21.07±0.29, 27.60±0.21, 34.13±0.44, 39.86±0.31, 45.96±0.61 mm, 54.13±0.37 mm, 16.16±0.46 mm, 9.81±0.35 mm, 2.75±0.30 mm, respectively. For the depth of the catheter end, the average value measured at PA was 6.70±0.31 mm. T 0°, TCA 5~25°, TCE 5~15° were 15.72±0.38 mm, 24.10±0.50 mm, 29.24±0.86 mm, 34.35±0.35 mm, 41.06±1.08 mm, 48.07±0.38 mm, 12.85±0.25 mm, 7.92±0.36 mm, 3.01±0.39 mm, respectively. The length of the lung apex was similar to that of chest PA when the angle of incidence was adjusted from 5° to 10° in the leg direction, and the depth of the catheter tip was most similar when the X-ray tube angle was incident at 10° in the head direction. Therefore, To change the X-ray tube angle according to the purpose of the examination during the chest AP radiography using 'S-align' function is considered necessary.

Evaluation of Approximate Exposure to Low-dose Ionizing Radiation from Medical Images using a Computed Radiography (CR) System (전산화 방사선촬영(CR) 시스템을 이용한 근사적 의료 피폭 선량 평가)

  • Yu, Minsun;Lee, Jaeseung;Im, Inchul
    • Journal of the Korean Society of Radiology
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    • v.6 no.6
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    • pp.455-464
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    • 2012
  • This study suggested evaluation of approximately exposure to low-dose ionization radiation from medical images using a computed radiography (CR) system in standard X-ray examination and experimental model can compare diagnostic reference level (DRL) will suggest on optimization condition of guard about medical radiation of low dose space. Entrance surface dose (ESD) cross-measuring by standard dosimeter and optically stimulated luminescence dosimeters (OSLDs) in experiment condition about tube voltage and current of X-ray generator. Also, Hounsfield unit (HU) scale measured about each experiment condition in CR system and after character relationship table and graph tabulate about ESD and HU scale, approximately radiation dose about head, neck, thoracic, abdomen, and pelvis draw a measurement. In result measuring head, neck, thoracic, abdomen, and pelvis, average of ESD is 2.10, 2.01, 1.13, 2.97, and 1.95 mGy, respectively. HU scale is $3,276{\pm}3.72$, $3,217{\pm}2.93$, $2,768{\pm}3.13$, $3,782{\pm}5.19$, and $2,318{\pm}4.64$, respectively, in CR image. At this moment, using characteristic relationship table and graph, ESD measured approximately 2.16, 2.06, 1.19, 3.05, and 2.07 mGy, respectively. Average error of measuring value and ESD measured approximately smaller than 3%, this have credibility cover all the bases radiology area of measurement 5%. In its final analysis, this study suggest new experimental model approximately can assess radiation dose of patient in standard X-ray examination and can apply to CR examination, digital radiography and even film-cassette system.

Sputtering방식을 이용한 Indium Thin oxide박막의 넓이에 따른 X-ray 검출기 특성 연구

  • Kim, Dae-Guk;Sin, Jeong-Uk;O, Gyeong-Min;Kim, Seong-Heon;Lee, Yeong-Gyu;Jo, Seong-Ho;Nam, Sang-Hui
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.321-322
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    • 2012
  • 의료용 방사선 장비는 초기의 아날로그 방식의 필름 및 카세트에서 진보되어 현재는 디지털 방식의 DR (Digital Radiography)이 널리 사용되며 그에 관한 연구개발이 활발히 진행되고 있다. DR은 크게 간접방식과 직접방식의 두 분류로 나눌 수 있는데, 간접방식은 X선을 흡수하면 가시광선으로 전환하는 형광체(Scintillator)를 사용하여 X선을 가시광선으로 전환하고, 이를 Photodiode와 같은 광소자로 전기적 신호로 변환하여 방사선을 검출하는 방식을 말하며, 직접 방식은 X선을 흡수하면 전기적 신호를 발생 시키는 광도전체(Photoconductor)를 사용하여 광도전체 양단 전극에 고전압을 인가한 형태를 취하고 있는 가운데, X선이 조사되면 일차적으로 광도전체 내부에서 전자-전공쌍(Electron-hole pair)이 생성된다. 이들은 광도전체 양단의 인가되어 있는 전기장에 의해 전자는 +극으로, 전공은 -극으로 이동하여 아래에 위치한 Active matrix array을 통해 방사선을 검출하는 방식이다. 본 연구에서는 직접방식 X-ray 검출기에서 활용되는 a-Se을 ITO (Indium Thin oxide) glass 상단에 Thermal evaporation증착을 이용하여 두께 $50{\mu}m$, 33 넓이로 증착 시킨 다음, a-Se상단에 Sputtering증착을 이용하여 ITO를 11 cm, 22 cm, $2.7{\times}2.7cm$ 넓이로 증착시켜 상하부의 ITO를 Electrode로 이용하여 직접방식의 X-ray검출기 샘플을 제작하였다. 제작 과정 중 a-Se의 Thermal evaporation증착 시, 저진공 $310^{-3}_{Torr}$, 고진공 $2.210^{-5}_{Torr}$에서 보트의 가열 온도를 두 번의 스텝으로 나누어 증착 시켰다. 첫 번째 스텝 $250^{\circ}C$, 두 번째 스텝은 $260^{\circ}C$의 조건으로 증착하여 보트 내의 a-Se을 남기지 않고 전량을 소모할 수 있었으며, 스텝간의 온도차를 $10^{\circ}C$로 제어하여 균일한 박막을 형성 할 수 있었다. Sputtering증착 시, 저진공 $2.510^{-3}$, 고진공 $310^{-5}$에서 Ar, $O_2$를 사용하여 100 Sec간 플라즈마를 생성시켜 ITO를 증착하였다. 제작된 방사선 각각의 검출기 샘플 양단의 ITO에 500V의 전압을 인가하고, 진단 방사선 범위의 70 kVp, 100 mA, 0.03 sec 조건으로 X-ray를 조사시켜 ITO넓이에 따른 민감도(Sensitivity)와 암전류(Dark current)를 측정하였다. 측정결과 민감도(Sensitivity)는 X-ray샘플의 두께에 따른 $1V/{\mu}m$ 기준 시, 증착된 ITO의 넓이가 11 cm부터 22 cm, $2.7{\times}2.7cm$까지 각각 $7.610nC/cm^2$, $8.169nC/cm^2$, $6.769nC/cm^2$로 22 cm 넓이의 샘플이 가장 높은 민감도를 나타내었으나, 암전류(Dark current)는 $1.68nA/cm^2$, $3.132nA/cm^2$, $5.117nA/cm^2$로 11 cm 넓이의 샘플이 가장 낮은 값을 나타내었다. 이러한 데이터를 SNR (Signal to Noise Ratio)로 합산 하였을 시 104.359 ($1{\times}1$), 60.376($2{\times}2$), 30.621 ($2.7{\times}2.7$)로 11 cm 샘플이 신호 대 별 가장 우수한 효율을 나타냄을 알 수 있었다. 따라서 ITO박막의 면적이 클수록 민감도는 우수하나 그에 따른 암전류의 증가로 효율이 떨어짐을 검증 할 수 있었으며, 이는 ITO면적이 넓어짐에 따른 저항의 증가로 암전류에 영향을 끼침을 할 수 있었다. 본 연구를 통해 a-Se의 ITO 박막 면적에 따른 전기적 특성을 검증할 수 있었다.

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Ecosysteme de I′Etang de Berre (Mediterranee nord-occidentale) : Caracteres Generales Physiques, Chimiques et Biologiques

  • Kim, Ki-Tai
    • Korean Journal of Environmental Biology
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    • v.22 no.2
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    • pp.247-258
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    • 2004
  • Climatological, hydrological and planktonical research studies, measurements of primary production and photosynthetic efficiency from December 1976 to December 1978 have been carried out in two brackish lakes: Lake Etang de Berre and Lake Etang de Vaine located in the French Mediterranean coast, in the region of Carry-le-Rouet located on the north-west Mediterranean near Marseilles, and in fresh water inflows from 4 Rivers (Touloubre, Durance, Arc, Durancole) to Lake Etang de Berre. Physico-chemical parameters were measured for this study: water temperature, salinity, density, pH, alcalinity, dissolved oxygen (% saturation), phosphate, nitrate, nitrite, silicate etc. Diverse biological parameters were also studied: photosynthetic pigments, phaeopigments, specific composition and biomass of phytoplankton, primary pelagic production etc. Climatical factors were studied: air-temperature, solar-radiation, evaporation, direction (including strength) of winds, precipitation and freshwater volume of the four rivers. The changes in Lake ‘Etang de Berre’ ecosystem depend on the quality of the water in the Durance River, and on the effects of seawater near the entrance of the Caronte Canal. The water quality of the lake varies horizontally and vertically as a result of atmospheric phenomena, maritime currents and tides. The distribution of water temperatures is generally heterogeneous. Southeasterly winds and the Northeasterly Mistral wind are important in the origins of circulated and mixed water masses. These winds are both frequent and strong. They have, as a result, a great effect on the water environment of Lake Etang de Berre. In theory, the annual precipitation in this region is well over eight times the water mass of the lake. The water of the Durance River flows into Lake Etang de Berre through the EDF Canal, amounting to 90% of the precipitation. However, reduction of rainfall in dry seasons has a serious effect on the hydrological characteristics of the lake. The temperature in the winter is partially caused by the low temperature of fresh water, particularly that of the Durance River. The hydrological season of fresh and brackish water is about one month ahead of the hydrological season of sea water in its vicinity. The salinity of Lake Etang de Berre runs approximately 3$\textperthousand$, except at lower levels and near the entrance to the Caronte Canal. However, when the volume of the Durance River water is reduced in the summer and fall, the salinity rises to 15$\textperthousand$. In the lake, the ratio of fresh water to sea water is six to one (6:1). The large quantities of seston conveyed by rivers, particularly the Durance diversion, strongly reduce the transparency in the brackish waters. Although the amount of sunshine is also notable, transparency is slight because of the large amount of seston, carried chiefly by Tripton in the fresh water of the Durance River. Therefore, photosynthesis generally occurs only in the surface layer. The transparency progressively increases from freshwater to open seawater, as mineral particles sink to the bottom (about 1.7kg $m^{-2}a^{-1}$ on the average in brackish lakes). The concentration of dissolved oxygen and the rate of oxygen saturation in seawater (Carry-le-Rouet) ranged from 5.0 to 6.0 $m\ell$ㆍ.$1^{-1}$, and from 95 to 105%, respectively. The amount of dissolved oxygen in Etang de Berre oscillated between 2.9 and 268.3%. The monographs of phosphate, nitrate, nitrite and silicate were published as a part of a study on the ecology of phytoplankton in these environments. Horizontal and vertical distributions of these nutriments were studied in detail. The recent diversion of the Durance River into Lake Etang de Berre has effected a fundamental change in this formerly marine environment, which has had a great impact in its plankton populations. A total of 182 taxa were identified, including 111 Bacillariophyceae, 44 Chlorophyceae, and 15 Cyanophyceae. The most abundant species are small freshwater algae, mainly Chlorophyceae. The average density is about $10^{8}$ cells $1^{-1}$ in Lake Etang de Berre, and about double that amount in Lake Etang de Vaine. Differences in phytoplankton abundance and composition at the various stations or at various depths are slight. Cell biovolume V (equivalent to true biomass), plasma volume VP (‘useful’ biomass) and, simultaneously. the cell surface area S and S/V ratio through the measurement of cell dimensions were computed as the parameters of phytoplankton productivity and metabolism. Pigment concentrations are generally very high on account of phytoplankton blooms by Cyanophyceae, Chlorophyceae and Cryptophyceae. On the other hand, in freshwaters and marine waters, pigment concentrations are comparatively low and stable, showing slight annual variation. The variations of ATP concentration were closely related to those of chlorophyll a and phytoplankton blooms only in marine waters. The carbon uptake rates ranged between 38 and 1091 mg$Cm^{-2}d^{-1}$, with an average surface value of 256 mg; water-column carbon-uptake rates ranged between 240 and 2310 mg$Cm^{-2}d^{-1}$, with an average of 810, representing 290 mg$Cm^{-2}$, per year 45 000 tons per year of photosynthetized carbon for the whole lake. Gross photosynthetic production measured by the method of Ryther was studied over a 2-year period. The values obtained from marine water(Carry-le-Rouet) ranged from 23 to 2 337 mg$Cm^{-2}d^{-1}$, with a weighted average of 319, representing about 110 gCm$^{-2}$ per year. The values in brakish water (Etang de Berre) ranged from 14 to 1778 mg$Cm^{-2}d^{-1}$, with a weighted average of 682, representing 250 mg$Cm^{-2}$ per year and 38 400 tons per year of photosynthesized carbon for the whole lake.

Pulse wave velocity and ankle brachial index in adolescents with essential hypertension (본태성 고혈압 청소년에서 pulse wave velocity와 ankle brachial index에 대한 연구)

  • Joo, Sun Young;Cho, Ki Young;Cho, Su Jin;Hong, Young Mi
    • Clinical and Experimental Pediatrics
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    • v.49 no.7
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    • pp.769-776
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    • 2006
  • Purpose : Pulse wave velocity(PWV) and ankle brachial index(ABI) are not only noninvasive methods used to assess arterial stiffness in adults, but also useful, simple ways to estimate the severity of hypertension, end stage renal disease and atherosclerosis in adults. But there are few studies on PWV and ABI in adolescents and children. In this study, hypertensive adolescents were compared to normal individuals to find out the usefulness of PWV as the index of progress in the disease. Methods : 413 teenagers were divided into three groups. The first group consisted of adolescents that only had hypertension(Group 1 : 23 teenagers). The second group consisted of the adolescents who had hypertension with obesity(Group 2 : 17 teenagers), and the last group was the normal subjects(Group 3 : 328 teenagers). Weight, height and body mass index were measured. Simultaneous measurements of systolic, diastolic and average blood pressure were obtained from the four extremities. PWV, ABI, ejection time and preejection period were also measured. Results : Right brachial-ankle PWV was significantly higher in both group 1 and group 2 compared with group 3, and significantly higher in group 2 compared with group 1. Likewise, left brachial-ankle PWV also showed significantly higher values in both group 1 and group 2 compared with group 3, and also higher values in group 2 compared with group 1. Positive correlations were found between the systolic, diastolic, average blood pressure and PWV. There were also positive correlations between the blood pressure and weight, body mass index. Conclusion : Higher PWV was demonstrated in adolescents with essential hypertension compared to normal subjects. Follow-up study is needed to evaluate the progress.

Responses and Toxicities of Risk-adapted Chemotherapy in Pediatric Intracranial Germ Cell Tumors (소아 두개 내 생식 세포종에서 위험군에 따른 화학요법의 치료 반응 및 독성)

  • You, Dong Kil;Lee, Soo Hyun;Yoo, Keon Hee;Sung, Ki Woong;Lim, Do Hoon;Shin, Hyung Jin;Koo, Hong Hoe
    • Clinical and Experimental Pediatrics
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    • v.48 no.2
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    • pp.186-190
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    • 2005
  • Purpose : The purpose of this study was to evaluate the responses and toxicities of risk-adapted chemotherapy in pediatric intracranial germ cell tumors(IC-GCT). Methods : Fourteen patients who were diagnosed as IC-GCT from October 2002 to December 2003 received chemotherapy as an initial treatment modality. The low risk(LR) group was defined as follows : Pure germinoma and normal AFP level. Beta-hCG level 50 mIU/mL or less. The others belonged to the high risk(HR) group. Chemotherapy was composed of cisplatin, cyclophosphamide, etoposide and vincristine. Double doses of cisplatin and cyclophosphamide was used in HR patients. Results : Pathologic confirmation was done in all but one. Median age at diagnosis was 11.6 yr (1.2-18.7 yr), and nine patients belonged to the HR group. Tumor markers were normalized after chemotherapy in all patients whose tumor markers had been elevated. Four LR patients(80 percent) and seven HR patients(77.8 percent) showed complete response(CR) at the end of chemotherapy. An additional two of the three patients with partial response(PR) achieved CR after radiation therapy (RT), and the remaining one relapsed before RT. Four LR and all HR patients experienced infectious episodes that required hospitalization. Four of the nine HR patients(44.4 percent) suffered from tinnitus, three of whom developed sensorineural hearing loss. All but one are surviving, event-free, with a median follow-up of 13.9 mo(8.1-22.3 mo). Conclusion : Risk-adapted cisplatin-based chemotherapy was effective even in HR patients, but regimen modification seems to be necessary to avoid an unacceptably high toxicity rate.