• Title/Summary/Keyword: dose response

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Measurement of the Spatial Dose Rates from Radioactive Patients during Nuclear Medicine Studies (핵의학 검사에서 환자로부터의 공간선량률 측정)

  • Park, Myeong-Hwan;Lee, Jon-Il
    • Journal of radiological science and technology
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    • v.25 no.1
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    • pp.73-76
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    • 2002
  • In order to evaluate the exposure to the radiologic technologists from patients who had been administrated with radiopharmaceuticals, we measured the spatial dose rates at 5 cm, 50 cm, and 100 cm from skin surface of patients using an proportional digital surveymeter, both 5 min after injection and right before the studies. In results, the exposure to the technologists in each procedure was small, compared nth the dose limits of the medical workers. However, the dose-response relationships in cancer and hereditary effects, referred to as the stochastic effects, have been assumed linear and no threshold models ; therefore, the exposure should be minimized. For this purpose, the measurements of spatial dose rate distributions were thought to be useful.

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Effects of Quercetin on the Immune Responses in Mice (Quercetin이 마우스의 면역반응에 미치는 영향)

  • 안영근;박영길;김정훈
    • YAKHAK HOEJI
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    • v.35 no.5
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    • pp.401-415
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    • 1991
  • Effects of quercetin on the specific and non-specific immune responses were studied in vivo. Quercetin at a dose of 2.5, 5, 10, 20 and 40 mg/kg were orally administered to ICR male mice once daily for 28 consecutive days. Cyclophosphamide was injected intraperitoneally to ICR mice with a single dose of 5 mg/kg 2 days before secondary immunization. Mice were sensitized and challenged with sheep red blood cells (S-RBC). Immune responses were evaluated by humoral and cellular immune reponses and non-specific immune response. The results of this study were summarized as followings; 1. Quercetin significantly decreased the body weight, and introduced the atrophy of liver, spleen and thymus gland dose-dependently, but increased the numbers of white blood cell. 2. Querectin significantly depressed the hemagglutination titer, Arthus reaction and hemolytic plaque forming cell. 3. Quercetin significantly depressed the delayed type hypersensitivity and rosette forming cell. 4. Quercetin at a dose of 2.5, 5 and 40 mg/kg significantly depressed phagocytic activity. 5. Quercetin at a dose of 10 and 20 mg/kg significantly increased natural killer cell activity.

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A Study on Dose-Response Models for Foodborne Disease Pathogens (주요 식중독 원인 미생물들에 대한 용량-반응 모델 연구)

  • Park, Myoung Su;Cho, June Ill;Lee, Soon Ho;Bahk, Gyung Jin
    • Journal of Food Hygiene and Safety
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    • v.29 no.4
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    • pp.299-304
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    • 2014
  • The dose-response models are important for the quantitative microbiological risk assessment (QMRA) because they would enable prediction of infection risk to humans from foodborne pathogens. In this study, we performed a comprehensive literature review and meta-analysis to better quantify this association. The meta-analysis applied a final selection of 193 published papers for total 43 species foodborne disease pathogens (bacteria 26, virus 9, and parasite 8 species) which were identified and classified based on the dose-response models related to QMRA studies from PubMed, ScienceDirect database and internet websites during 1980-2012. The main search keywords used the combination "food", "foodborne disease pathogen", "dose-response model", and "quantitative microbiological risk assessment". The appropriate dose-response models for Campylobacter jejuni, pathogenic E. coli O157:H7 (EHEC / EPEC / ETEC), Listeria monocytogenes, Salmonella spp., Shigella spp., Staphylococcus aureus, Vibrio parahaemolyticus, Vibrio cholera, Rota virus, and Cryptosporidium pavum were beta-poisson (${\alpha}=0.15$, ${\beta}=7.59$, fi = 0.72), beta-poisson (${\alpha}=0.49$, ${\beta}=1.81{\times}10^5$, fi = 0.67) / beta-poisson (${\alpha}=0.22$, ${\beta}=8.70{\times}10^3$, fi = 0.40) / beta-poisson (${\alpha}=0.18$, ${\beta}=8.60{\times}10^7$, fi = 0.60), exponential (r=$1.18{\times}10^{-10}$, fi = 0.14), beta-poisson (${\alpha}=0.11$, ${\beta}=6,097$, fi = 0.09), beta-poisson (${\alpha}=0.21$, ${\beta}=1,120$, fi = 0.15), exponential ($r=7.64{\times}10^{-8}$, fi = 1.00), betapoisson (${\alpha}=0.17$, ${\beta}=1.18{\times}10^5$, fi = 1.00), beta-poisson (${\alpha}=0.25$, ${\beta}=16.2$, fi = 0.57), exponential ($r=1.73{\times}10{-2}$, fi = 1.00), and exponential ($r=1.73{\times}10^{-2}$, fi = 0.17), respectively. Therefore, these results provide the preliminary data necessary for the development of foodborne pathogens QMRA.

The Pattern of Failure after Definitive Radiotherapy for Squamous Cell Carcinoma of the Lung (편평상피 세포성 폐암의 방사선치료 실패 양상)

  • Jang Yang Suk;Kim Jae Cheol;Ryu Samuel;Park In Kyu
    • Radiation Oncology Journal
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    • v.7 no.1
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    • pp.45-50
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    • 1989
  • From Feb.1985 to Feb.1988,76 patients with squamous cell carcinoma of the lung treated at the Department of Therapeutic Radiology in Kyungpook National University Hospital were available for the analysis of this study. All patients received radiation of 4000cGy-6600cGy with curative aim. The overall rate of complete response was 25.0% and partial response was 452.6% The complete and partial regression of tumor was 14.3% in patients treated with dose below 5000cGy and 84.1% in the group treated with dose above 5000cGy (p<0.01). The complete response was seen only in the group of patients received radiation at least 6000cGy. The patterns of failure were as follows. The rate of initial intrathoracic recurrence was 52.6% in patients with complete response. The overall rate of failure was 68.8%. Distant metastasis was found in 47.4% of patients. Bone, contralateral lung, and brain were common metastatic sites in decreasing order All of the distant metastases and 80% of local recurrences were found within the first year after treatment.

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The Effects of Water Extract of Genus Panax on Rat Blood Vessels (Panax 속 한약재가 흰쥐 혈관운동성에 미치는 영향에 관한 비교 연구)

  • 유기덕;최호영;이재성;안덕균;김형환
    • The Journal of Korean Medicine
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    • v.25 no.1
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    • pp.60-71
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    • 2004
  • Objectives : We have examined the relaxational response to the water extract of genus Panax in rat thoracic aorta and mesenteric artery. Methods : Segments of thoracic aorta and mesenteric artery obtained from rats immediately after delivery were mounted in organ baths superfused on a polygraph. Results : We found that the thoracic aorta segments responded to the water extract of genus Panax with a dose-dependent vasorelaxation. At $10^{-5}m$ 5-hydroxytrptamine (5-HT), the maximal contraction force were 94.9% of the maximum KCl-response. At $10^{-5}m$ 5-HT - induced contraction, The contractile response of thoracic aortic rings were inhibited by 54.7%, 36.3% and 31.3% after addition of the high concentration (100 mg/ml) of water extract of Panax ginseng, Panax japonicus and Panax quinquefolium. The contractile response of mesenteric arteries were inhibited by 88.3%, 87.7%, and 70.3% after addition of the high concentration (100 mg/ml) of water extract of Panax ginseng, Panax japonicus and Panax quinquefolium. Conclusions : In conclusion, water extract of genus Panax - induced relaxation in the isolated rat thoracic aorta and mesenteric artery were composed of endothelium - independent relaxation and dose - dependent relaxation.

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Effects of Antiprogesterone (RU486) and Antiestrogen (Tamoxifen) on Ovulatory Response and Oocyte Quality in Rats Primed with Pregnant Mare Serum Gonadotropin (PMSG 전처리한 쥐에 있어서 Antiprogesterone(RU486)과 Antiestrogen(Tamoxifen)이 배란과 Oocyte에 미치는 영향)

  • 윤영원;권종국;유규연
    • Journal of Embryo Transfer
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    • v.4 no.1
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    • pp.46-55
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    • 1989
  • The effects of an antiprogesterone (RU 486) and an antiestrogen (tamoxifen) on ovulatory response and oocyte morphology were examined in pregnant mare serum gonadotropin (PMSG)-primed immatare female rats (28 days of age): a comparison has been made on two different regirnens primed with a "control" dose (4 IU) and a "superovulatory" dose (40 IU) of PMSG. Females for control control regimen received three consecutive injections of lmg RU486, lmg tamoxifen, or vehicle at 24, 36 and 48hr, and were killed at 72l'r after PMSG. Animals for superovalatory regimen received lmg RU486, 2.5mg tamoxifen, or vehicle fouowlag the injection schedule comparable to control regimen, and were killed at 60 and 72hr after PMSG. Compared to vehicle group, there was a significant reduction in ovulatory response as judged by the proportion of rats ovulating andi or by the mean number of oocytes per rat for each treatment of RU486 and tamoxifen in both regimens. The activity of tamoxifen in inhibiting the ovulatory response was greater in control, but less in superovulatory regimen than that of RU486 based on the dose employed for each antisteroid. In both regimens, RU 486 did not have any effect 6n the changes in the proportion of degenerate oocytes as well as ovarian weight, well tamoxifen treatment resulted in a marked promotion of oocyte degeneration as well as a great reduction in ovarian weight, compared to each parameter of vehicle group. RU486 treatment in each regimen did not alter the serum levels of any steroid hormones observed. Howerver, tamoxifen treatment was associated with significant increases in serum 17$\beta$-estradiol and decreases in progesterone in both regimens; also significant increases in androgens in superovulatory regimen. The results illustrate the relative inhibitory activity of RU486 and tamoxifen indicating major steroid hormone involved in PMSG-induced ovulation: 17$\beta$-estradiol for control and progesterone for superovulatory regimen. It also appears that tamoxifen-associated elevation of circulating 17$\beta$-estradiol andi or androgens could be in part, a contributing factor to the promotion of oocyte degeneration presumably by producing a hostile oviductal environment after ovulation.ent after ovulation.

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Expression patterns of innate immunity-related genes in response to polyinosinic:polycytidylic acid (poly[I:C]) stimulation in DF-1 chicken fibroblast cells

  • Jang, Hyun-Jun;Song, Ki-Duk
    • Journal of Animal Science and Technology
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    • v.62 no.3
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    • pp.385-395
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    • 2020
  • Polyinosinic:polycytidylic acid (poly[I:C]) can stimulate Toll-like receptor 3 (TLR3) signaling pathways. In this study, DF-1 cells were treated with poly(I:C) at various concentrations and time points to examine the comparative expression patterns of innate immune response genes. The viability of DF-1 cells decreased from 77.41% to 38.68% when cells were treated different dose of poly(I:C) from 0.1 ㎍/mL to 100 ㎍/mL for 24 h respectively. The expressions of TLR3, TLR4, TLR7, TLR15, TLR21, IL1B, and IL10 were increased in dose- and time-dependent manners by poly(I:C) treatment. On the contrary, the expression patterns of interferon regulatory factors 7 (IRF7), Jun proto-oncogene, AP-1 transcription factor subunit (JUN), Nuclear Factor Kappa B Subunit 1 (NF-κB1), and IL8L2 were varied; IRF7 and IL8L2 were increasingly expressed whereas the expressions of JUN and NF-κB1 were decreased in a dose-dependent manner after they were early induced. In time-dependent analysis, IRF7 expression was significantly upregulated from 3 h to 24 h, whereas JUN and NF-κB1 expressions settled down from 6 h to 24 h after poly(I:C) treatment although they were induced at early time from 1 h to 3 h. Poly(I:C) treatment rapidly increased the expression of IL8L2 from 3 h to 6 h with a plateau at 6 h and then the expression of IL8L2 was dramatically decreased until 24 h after poly(I:C) treatment although the expression level was still higher than the non-treated control. These results may provide the basis for understanding host response to viral infection and its mimicry system in chickens.

The Response of Parenchymal Mass and Airway Obstruction from Lung Cancer to Radiation Therapy (단순 흉부 X-선 사진상 폐암 소견에 대한 방사선 치료의 효과 -단기 추적 조사를 중심으로-)

  • Kang, Cheol-Hoon;Shin, Sei-One;Kim, Myung-Se
    • Radiation Oncology Journal
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    • v.7 no.2
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    • pp.227-233
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    • 1989
  • From April 1986 to Dec 1988, fifty one patients with carcinoma of lung were treated by radiation therapy in Department of Therapeutic Radiology, Yeungnam University Hospital Of the 51 patients, $31(61\%)$ were squamous cell ca, $8(15.7\%)$ were small cell ca, and remained $4(7.9\%)$ were other cell types. Total radiation dose was average $64Gy (60\~75 Gy)$ for group A and 45Gy $(40\~59Gy)$ for group B. The mass regression and the response of airway obstruction to radiation therapy was established on the basis of follow up chest X-ray. The mass regression above $50\%$ of total volume was noted in 23 patients $(74.2\%)$ among 31 patients and the difference between two groups was not seen. In squamous cell ca, however, the mass regression rate (above $50\%$ of total volume) was $83.3\%$ (10/12) in group A compared to $50\%$ (3/6) in group B(p<0.05). The alleviation of airway obstruction was noted as follows. In group A, CR $42.9\%$, PR $35.7\%$, no response $21.4\%$ and in group B, CR $55.6\%,\;PR\;33.3\%$, no response $11.1\%$. But, in squamous cell ca, responsiveness is higher than group B. The study indicates that the importance of higher radiation dose in the management of primary tumor mass and airway obstruction caused by lung cancer especially squamous cell ca. So, meticulous treatment planning and multimodality combination therapy without increasing si.do elect or complication is recommended in management of inoperable bronchogenic carcinoma.

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Relationship between Bronchial Sensitivity and Bronchial Reactivity in Asthma (기관지천식 환자에서 기관지 감수성과 기관지 반응성에 관한 연구)

  • Seo, Ki-Youl;Chang, Jung-Hyun;Cheon, Seon-Hee
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.2
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    • pp.341-350
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    • 1998
  • Background: Airway hyperreponsiveness is a cardinal feature of asthma. It consists of both an increased sensitivity of the airways, as indicated by a smaller concentration of a constrictor agonist needed to initiate the brochoconstrictor response and an increased reactivity, increments in response induced subsequent doses of constrictor, as manifested by slopes of the dose-response curve. The purpose of this study is to observe the relationship between bronchial sensitivity and reactivity in asthmatic subjects. Method: Inhalation dose-response curves using methacholine were plotted in 56 asthmatic subjects. They were divided into three groups(mild, moderate and severe) according to clinical severity of bronchial asthma. PC20 were determined from the dose-response curve as the provocative concentration of the agonist causing a 20% fall in FEVl. PC40 were presumed or determined from the dose response curve, using the PC20 and the one more dose after PC20. Reactivity was calculated from the dose-response curve regression line, connecting PC20 with PC40. Results: PC20 were 1.83mg/ml in mild group, 0.96mg/ml in moderate, and 0.34mg/ml in severe. PC40 were 7.l7mg/ml in mild group, 2.34mg/ml in moderate, and 0.75mg/ml in severe. Reactivity were $24.7{\pm}17.06$ in mild group, $46.1{\pm}22.l0$ in moderate, and $59.0{\pm}5.82$ in severe. There was significant negative correlation between PC20 and reactivity (r= -0.70, P<0.01). Conclusion: Accordingly, there was significant negative correlation between bronchial sensitivity and brochial reactivity in asthmatic subjects. However, in some cases, there were wide variations in terms of the reactivity among the subjects who have similar sensitivity. So both should be assessed when the bronchial response tor bronchoconstrictor agonists is measured.

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