• Title/Summary/Keyword: Dose rate assessment

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Evaluation between 3.0 T vs 1.5 T MRI in Detection of Brain Metastasis using Double Dose Gd-DTPA (뇌전이 종양의 발견에 있어서 Doble dose Gd-DTPA를 이용한 3 T MRI와 1.5 T MRI간의 비교연구)

  • Chung, Woo-Suk;Kim, Hyung-Jung;Ahn, Chul-Min;Lee, Jae-Hoon;Hur, Jin;Cho, Eung-Hyuck;Chung, Tae-Sub
    • Investigative Magnetic Resonance Imaging
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    • v.9 no.2
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    • pp.101-108
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    • 2005
  • Purpose : Early detection of small brain metastases is important. The purpose of this study was to compare the detectability of brain metastases according to the size between 1.5 T and 3.0 T MRI. Materials and Methods : We reviewed 162 patients with primary lung cancer who were examined for TNM staging. After administration of double dose of Gd-DTPA, MR imaging was performed with SPGR by 3.0 T MRI and then with T1 SE sequence by 1.5 T MRI. In each patient, three readers performed qualitative assessment. Sensitivity, positive predictive value, and diagnostic accuracy were calculated in 3.0 T and 1.5 T MRI according to size. Using the signal intensity (SI) measurements between the metastatic nodules and adjacent tissue, nodule-to-adjacent tissue SI ratio was calculated. Results : Thirty-one of 162 patients had apparent metastatic nodules in the brain at either 1.5 T or 3.0 T MR imaging. 143 nodules were detected in 3.0 T MRI, whereas 137 nodules were detected at 1.5 T MRI. Six nodules, only detected in 3.0 T MRI, were smaller than 3.0 mm in dimension. Sensitivity, positive predictive value, and diagnostic accuracy in 3.0 T MRI were 100 %, 100 %, and 100 % respectively, and in 1.5 T MRI were 95.8%, 88.3%, and 85.1% respectively. SI ratio was significantly higher in the 3.0 T MRI than 1.5 T MRI (p=0.025). Conclusion : True positive rate of 3.0 T MRI with Gd-DTPA was superior to 1.5 T MRI with Gd-DTPA in detection of metastatic nodules smaller than 3.0 mm.

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ANALYSIS OF THE LiF:Mg,Cu,Si TL AND THE LiF:Mg,Cu,P TL GLOW CURVES BY USING GENERAL APPROXIMATION PLUS MODEL

  • Chang, In-Su;Lee, Jung-Il;Kim, Jang-Lyul;Oh, Mi-Ae;Chung, Ki-Soo
    • Journal of Radiation Protection and Research
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    • v.34 no.4
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    • pp.155-164
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    • 2009
  • In this paper, we used computerized glow curve deconvolution (CGCD) software with several models for the simulation of a TL glow curve which was used for analysis. By using the general approximation plus model, parameters values of the glow curve were analyzed and compared with the other models parameters (general approximation, mixed order kinetics, general order kinetics). The LiF:Mg,Cu,Si and the LiF:Mg,Cu,P material were used for the glow curve analysis. And we based on figure of merits (FOM) which was the goodness of the fitting that was monitored through the value between analysis model and TLD materials. The ideal value of FOM is 0 which represents a perfect fit. The main glow peak makes the most effect of radiation dose assessment of TLD materials. The main peak of the LiF:Mg,Cu,Si materials has a intensity rate 80.76% of the whole TL glow intensity, and that of LiF:Mg,Cu,P materials has a intensity rate 68.07% of the whole TL glow intensity. The activation energy of LiF:Mg,Cu,Si was analyzed as 2.39 eV by result of the general approximation plus(GAP) model. In the case of mixed order kinetics (MOK), the activation energy was analyzed as 2.29 eV. The activation energy was analyzed as 2.38 eV by the general order kinetics (GOK) model. In the case of LiF:Mg,Cu,P TLD, the activation energy was analyzed as 2.39 eV by result of the GAP model. In the case of MOK, the activation energy was analyzed as 2.55 eV. The activation energy was analyzed as 2.51 eV by the GOK model. The R value means different ratio of retrapping-recombination. The R value of LiF:Mg,Cu,Si TLD main peak analyzed as $1.12\times10^{-6}$ and $\alpha$ value analyzed as $1.0\times10^{-3}$. The R of LiF:Mg,Cu,P TLD analyzed as $7.91\times10^{-4}$, the $\alpha$ value means different ratio of initial thermally trapped electron density-initial trapped electron density (include thermally disconnected trap electrons density). The $\alpha$ value was analyzed as $9.17\times10^{-1}$ which was the difference from LiF:Mg,Cu,Si TLD. The deep trap electron density of LiF:Mg,Cu,Si was higher than the deep trap electron density of LiF:Mg,Cu,P.

Radiation Treatment of Esophageal Cancer (식도암의 방사선치료)

  • Oh W. Y.;Suh C. O.;Kim G. E.
    • Radiation Oncology Journal
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    • v.3 no.1
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    • pp.41-50
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    • 1985
  • 63 patients who were irradiated with a goal of long term control among 101 patients with esophageal cancer seen during an 11 fears period between Jan, 1970 and Dec, 1980 at Yonsei Cancer Center in Seoul, Korea have retrospectively analysed. 52(82.5%) among the 63 Patients were confirmed to have epidermoid carcinoma in the histology. 46 cases(73.0%) except 17 cases of $T_1$, were locally or far advanced extension. Tumor dose of radical radiation in the management of esophageal cancer had delivered from 50 Gy to 74 Gys. 2 Gys daily fractions, between 5weeks and 8 weeks. After 1 month from the completion of radiation, 23 of the 63 patients had a repeat barium esophagogram for the assessment of tumor response, there had showed 7 cases of complete response and 15 cases of partial response. 45(71.4%) patients were followed up and the remaining 18 patients were lost to follow-up within 1 year after the completion of irradiation. Actuarial overall 3 and 5 years survival rate of all 63 Patients were 11.8% and 8.8%, respectively. The actuarial 3 and 5 years survival rates of 17 cases of $T_1$, esophageal cancer were 24.7% and 20.8%. Statistically, there was no significant difference in survival rate according to tumor location (p>0.05). Radical Radiotherapy, Esophageal Cancer

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Prioritizing Environmental Risks of Veterinary Antibiotics Based on the Use and the Potential to Reach Environment (사용량과 잠재적 환경 유출 가능성을 기준으로 한 축산용 항생제의 우선순위 결정)

  • Seo, Young-Ho;Choi, Jun-Keun;Kim, Seung-Kyeong;Min, Hwang-Kee;Jung, Yeong-Sang
    • Korean Journal of Soil Science and Fertilizer
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    • v.40 no.1
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    • pp.43-50
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    • 2007
  • Veterinary antibiotics have been widely used to increase feed efficiency, to prevent disease, and to promote growth as well as to control disease. The antibiotics administered can be excreted through the urine and feces. One of the major routes of veterinary antibiotics entering soil and water environment is via the application of animal manure to agricultural land as an organic fertilizer source. Since little is known about impacts of antibiotics on the environment, this study was conducted to prioritize the veterinary antibiotics based on the consumption and potential to reach the environment. Among 83 veterinary antibiotics consumed in Korea, ten antibiotics were used at the greater dose than 25 Mg in 2004. Potential to reach the environment was determined according to excretion rate after administered to animals and sorption affinity to soil solids after applied to agricultural land. Seventeen antibiotic active ingredients (Ais) were classified as 'High' priority in terms of the potential to reach the environment. An overall priority score was determined by combining priority score based on consumption with the degree of potential environment exposure. Twenty veterinary antibiotic AIs were classified as 'Very high' or 'High' priority requiring detailed assessment. The antibiotic AIs were identified four aminoglycosides, two macrolides, two penicillins, five sulfonamides, three tetracyclines, two quinolones, and two miscellaneous. Eight veterinary antibiotic AIs including amoxicillin, carbadox, chlortetracycline, neomycin, oxytetracycline, sulfamethazine, sulfathiazole, and tylosin were identified to have a greater priority of environmental risk in Korea.

Quantitative Microbial Risk Assessment of Pathogenic Vibrio through Sea Squirt Consumption in Korea (우렁쉥이에 대한 병원성 비브리오균 정량적 미생물 위해평가)

  • Ha, Jimyeong;Lee, Jeeyeon;Oh, Hyemin;Shin, Il-Shik;Kim, Young-Mog;Park, Kwon-Sam;Yoon, Yohan
    • Journal of Food Hygiene and Safety
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    • v.35 no.1
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    • pp.51-59
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    • 2020
  • This study evalutated the risk of foodborne illness from Vibrio spp. (Vibrio vulnificus and Vibrio cholerae) through sea squirt consumption. The prevalence of V. vulnificus and V. cholerae in sea squirt was evaluated, and the predictive models to describe the kinetic behavior of the Vibrio in sea squirt were developed. Distribution temperatures and times were collected, and they were fitted to probabilistic distributions to determine the appropriate distributions. The raw data from the Korea National Health and Nutrition Examination Survey 2016 were used to estimate the consumption rates and amount of sea squirt. In the hazard characterization, the Beta-Poisson model for V. vulnificus and V. cholerae infection was used. With the collected data, a simulation model was prepared and it was run with @RISK to estimate probabilities of foodborne illness by pathogenic Vibrio spp. through sea squirt consumption. Among 101 sea squirt samples, there were no V. vulnificus positive samples, but V. cholerae was detected in one sample. The developed predictive models described the fates of Vibrio spp. in sea squirt during distribution and storage, appropriately shown as 0.815-0.907 of R2 and 0.28 of RMSE. The consumption rate of sea squirt was 0.26%, and the daily consumption amount was 68.84 g per person. The Beta-Poisson model [P=1-(1+Dose/β)] was selected as a dose-response model. With these data, a simulation model was developed, and the risks of V. vulnificus and V. cholerae foodborne illness from sea squirt consumption were 2.66×10-15, and 1.02×10-12, respectively. These results suggest that the risk of pathogenic Vibrio spp. in sea squirt could be considered low in Korea.

The Effect of the Histidine-Tryptophan-Ketoglutarate (HTK) Solution on Myocardial Protection in Isolated Rat Heart (흰쥐의 적출심장에서 HTK 용액의 심근보호 효과)

  • 송원영;장봉현;김규태
    • Journal of Chest Surgery
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    • v.37 no.8
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    • pp.632-643
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    • 2004
  • Background: The Histidine-Tryptophan-Ketoglutarate (HTK) solution has been shown to provide the excellent myocardial protection as a cardioplegia. The HTK solution has relatively low potassium as an arresting agent of myocardium, and low sodium content, and high. concentration of histidine biological buffer which confer a buffering capacity superior to that of blood.. Since HTK solution has an excellent myocardial protective ability, it is reported to protect myocardium from ischemia for a considerable time (120 minutes) with the single infusion of HTK solution as a cardioplegia. The purpose of this study is to evaluate the cardioprotective effect of HTK solution on myocardium when the ischemia is. exceeding 120 minutes at two different temperature (10 to 12$^{\circ}C$, 22 to 24$^{\circ}C$) using the Langendorff apparatus, Material and Method: Hearts from Sprague-Dawley rat, weighing 300 to 340 g, were perfused with Krebs-Henseleit solution at a perfusion pressure of 100 cm $H_2O$. After the stabilization, the heart rate, left ventricular developed pressure (LVDP), and coronary flow were measured. Single dose of HTK solution was infused into the ascending aorta of isolated rat heart and hearts were preserved at four different conditions. In group 1 (n=10), hearts were preserved at deep hypothermia (10∼12$^{\circ}C$) for 2 hours, in group 2 (n=10), hearts were preserved at moderate hypothermia (22∼24$^{\circ}C$) for 2 hours, in group 3 (n=10), hearts were preserved at deep hypothermia for 3 hours, and in group 4 (n=10), hearts were preserved at moderate hypothermia for 3 hours. After the completion of the preservation, the heart rate, left ventricular developed pressure, and coronary flow were measured at 15 minutes, 30 minutes, and 45 minutes after the initiation of reperfusion to assess the cardiac function. Biopsies were also done and mitochondrial scores were counted in two cases of each group for ultrastructural assessment. Result: The present study showed that the change of heart rate was not different between group 1 and group 2, and group 1 and group 3. The heart rate was significantly decreased at 15 minutes in group 4 compared to that of group 1 (p<0.05 by ANCOVA). The heart rate was recovered at 30 minutes and 45 minutes in group 4 with no significant difference compared to that of group 1. The decrease of LVDP was significant at 15 minutes, 30 minutes and 45 minutes in group 4 compared to that of group 1 (p < 0.001 by ANCOVA). Coronary flow was significantly decreased at 15 minutes, 30 minutes, and 45 minutes in group 4 compared to that of group 1 (p < 0.001 by ANCOVA). In ultrastructural assessment, the mean myocardial mitochondrial scores in group 1, group 2, group 3, and group 4 were 1.02$\pm$0.29, 1.52$\pm$0.26, 1.56$\pm$0.45, 2.22$\pm$0.44 respectively. Conclusion: The HTK solution provided excellent myocardial protection regardless of myocardial temperature for 2 hours. But, when ischemic time exceeded 2 hours, the myocardial hemodynamic function and ultrastructural changes were significantly deteriorated at moderate hypotherma (22∼ 24$^{\circ}C$). This indicates that it is recommended to decrease myocardial temperature when myocardial ischemic time exceeds 2 hours with single infusion of HTK solution as a cardioplegia.

Adverse Effects of Ma-huang according to Dose : A Randomized Double-Blind Placebo-Controlled Pilot Study (마황용량에 따른 이상반응에 관한 예비연구: 무작위배정이중맹검시험)

  • Hsing, Li-Chang;Lee, Tae-Ho;Son, Dong-Hyug;Yeo, Jin-Ju;Yang, Chang-Sop;Seo, Eui-Seok;Jang, In-Soo
    • The Journal of Internal Korean Medicine
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    • v.27 no.1
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    • pp.188-196
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    • 2006
  • Background: Ma-huang (Ephedra sinica) has been widely used to treat respiratory disease in oriental medicine for over a hundred years. Ma-huang preparations contain approximately 1.25% ephedrine alkaloids. Recently, the ephedra alkaloids have received much press lately due to adverse effects in those using whole extracts as 'dietary supplements' for weight loss or athletic performance enhancement, and these reports are troubling given the increasing use of Ma-huang by the general public. The purpose of this report is to determine the proper dosage to minimize adverse effects and maximize the potential curative value. Objectives : The object of this study was to find an effective yet low risk dosage of Ma-huang. Methods : The study was designed as a double-blind randomized placebo-controlled trial. The subjects of this study were 26 adults between 20 to 40 of age who agreed to participate in this study. They were allocated through randomization into three groups. Each group took three opaque capsules three times a day. A group (N=9) took one Ma-huang capsule and two placebo capsules, B group (N=8) took two Ma-huang capsules and one placebo capsule, C group (N=9) took three Ma-huang capsules. The total trial periods was two days. To compare the adverse effects of Ma-huang according to dosage, blood pressure and pulse were checked, and other adverse effects were assessed using a morning questionnaire, patient's global assessment scale and Wong-Baker faces pain rating. Results : The following result were obtained: 1. After taking 18 g of Ma-huang per day, pulse rate had a significant increase. 2. After taking more than 6 g of Ma-huang per day, palpitation would be increased significantly. 3. After taking more than 18 g of Ma-huang per day, tiredness would be increased significantly. Conclusion: According to the results, 12 g of Ma-huang per day will minimize adverse effects and maximize the potential curative value.

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Determinants of Erythropoietin Hyporesponsiveness in Management of Anemia in Hemodialysis Patients (혈액투석 환자의 빈혈관리에서 Erythropoietin 반응에 영향을 미치는 인자)

  • Shin, Seung-Hee;Ji, Eun-Hee;Lee, Young-Sook;Oh, Jung-Mi
    • Korean Journal of Clinical Pharmacy
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    • v.21 no.2
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    • pp.122-130
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    • 2011
  • Objective: Although recombinant human erythropoietin (rhEPO) has revolutionized the treatment of anemia in chronic kidney disease (CKD) receiving hemodialysis (HD) with no need of blood transfusion, some patients have a blunted or appear to be resistant to rhEPO. There is a controversy in the causes of rhEPO resistance in maintenance HD patients with anemia. This study is to examine current anemia treatment outcomes and the factors influencing the rhEPO responsiveness in HD patient with CKD. Methods: The clinical parameters or factors relating to erythrompoietin treatment outcomes and erythropoietin responsiveness were collected from the HD patients in two large dialysis centers for three months. The collected paramenters included serum iron, total iron biding capacity (TIBC), transferrin saturation rate, ferritin, albumin, intact PTH, C-reactive protein (CRP), nPCR and medications such as an angiotensin converting enzyme inhbitor, an angiotension II receptor blocker and an HMG-CoA reductase inhibitor (HMG-CoA RI). The data were analyzed to examine the degree of acheiveing the anemia treatment goal and factors relating to ERI. Results: Among total 111 patients, 42 (42.3%) and 47 (37.8%) patients achieved the target Hct and Hb based on the Health Insurance Review and Assessment Services (HIRA) reimbursement criteria. In the higher ERI group (upper quartile), the patients had higher CRP levels (0.5 mg/dl) (p=0.0096), and lower TIBC score (<$240{\mu}g/dl$) (p=0.0027), and less patients were taking HMG-CoA RI (p=0.0019). Male patients (p=0.0204), patients with high TIBC score ($R^2$=0.084, p=0.0021) and patients taking HMG-CoA RI (p=0.0052) required to administer less dose of rhEPO meaning higher erythropoietin responsiveness. Conclusion: Less than 50% of CKD patients were achieving the goals of anemia by erythropoietin administration in large hospitals in Korea even though the goals were lower than those of NKF-K/DOQI practice guideline. The factors influencing ERI were sex, TIBC and HMG-CoA RI administration status, and neither an ACEI nor an ARB did not influence ERI.

Assessment on Nitrous Oxide (N2O) Emissions different Nitrogen Application Rates during the Red Pepper Cultivation in Flat Upland

  • Lee, Jong-Eun;Yun, Yeo-Uk;Lee, Jin-Il;Nam, Yun-Gyu;Kim, Gun-Yeob;Kim, Sun-Ju
    • Korean Journal of Soil Science and Fertilizer
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    • v.47 no.1
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    • pp.59-65
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    • 2014
  • Generally, nitrogen (N) fertilization higher than the recommended dose is applied during vegetable cultivation for increasing in productivity. However, excessive N application rate beyond plant requirement could cause adverse environmental impact such as nitrate leaching and nitrous oxide emission. In this experiment, the impacts of N fertilization was studied on nitrous oxide ($N_2O$) emission to standardize the optimum fertilization level for minimizing of $N_2O$ emission as well as most of the crop productivity. Herein, we assessed the $N_2O$ emission in the flat upland soil which was cultivated with different N application rates on red pepper for 3 years (2010~2012). $N_2O$ emission was measured in chemical N fertilizer amounts 0 (N 0), 95 (N 0.5), 190 (N 1.0), $380(N_2.0)kgha^{-1}$ by using the abnormal shape chamber closed repeating three times. In average for 3 years, the total $N_2O$ emissions of each treatment in field of soybean were 2.110 (N 0), 3.165 (N 0.5), 5.039 (N 1.0), and $7.228(N_2.0)kgN_2Oha^{-1}yr^{-1}$, respectively. And then the primary regression between nitrogen fertilizer amount and the total $N_2O$ emission was showed as y = 0.0138x + 2.0942 ($r^2=0.9885$), and an average of the emission factor was $EF_1$ 0.0148(0.0118~0.0191) $N_2O-NkgN^{-1}kg^{-1}$ from 2010 to 2012. The result was a little higher than the emission default of the IPCC 1996 Guideline ($EF_1$ 0.0125) when the results are converted into $N_2O$ emission factor.

Assessment of DNA Damage using an Alkaline Single Cell Gel Electrophoresis (SCGE) Comet Assay and Toxic Effects in Chickens by T-2 Toxin Treatment (T-2 toxin을 투여한 닭에서 Comet assay 방법을 이용한 DNA 손상 평가와 독성)

  • Hah Dae-Sik;Heo Jung-Ho;Lee Kuk-Cheon;Cho Myung-Heui;Kim Kuk-Hun;Kim Chung-Hui;Lue Jae-Du;Lee Seung-Hwan;Kim Gon-Sup;Kim Eui-Gyung;Kim Jong-Shu
    • Toxicological Research
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    • v.22 no.2
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    • pp.75-85
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    • 2006
  • This study was designed to evaluate the possible DNA damaging effects of T-2 toxin using an alkaline single cell gel electrophoresis (SCGE) comet assay and also to investigate toxic effects in chickens. A total of 20 chickens were used in these experiments. Graded concentrations of dietary T-2 toxin (0, 4, 8, and $16{\mu}g/g$ of diet) were given to groups of 5 broiler chickens. In comet assay, The DNA damage was analysed by the tail extent moment (TEM) and tail length (TL), which were used as markers of DNA strand breaks in SCGE. A significant dose-dependent increase in the extent of DNA migration as well as in the percentage of cells with tails was observed after treatment with T-2 toxin (P<0.05). Treatment with the low T-2 toxin ($4{\mu}/g$ of diet) induced a relatively low level of DNA damage in comparison with the high T-2 toxin ($16{\mu}/g$ of diet) group. The growth rate was significantly reduced by concentrations of 8, and $16{\mu}/g$ of diet (P < 0.05). The feed conversion ratio were significantly affected by any concentrations (P < 0.05). The relative weight of the spleen, and lung was decreased by the growth inhibitory concentrations. The bursa of Fabricius, thymus, and kid- ney were decreased in relative weight by concentrations of $16{\mu}/g$ of diet. The relative weight of the liver and heart were unaffected. The hemoglobin (Hb), hematocrit (HCT), and mean corpuscular hemoglobin (MCH) were decreased at concentration of $16{\mu}/g$ of diet. As compared with control chickens, there was no marked change in serum components except uric acid in T-2 treated chickens. All lymphoid tissues retained atrophic and lymphoid cell depletion throughout the three weeks trial.