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New Fungicides: Opportunities and Challenges - A Case Study with Dimethomorph

  • Spadafora, V. J.;Sieverding, E.
    • Proceedings of the Korean Society of Plant Pathology Conference
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    • 1998.06a
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    • pp.50-69
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    • 1998
  • Dimethomorph is a novel fungicide with a high level of activity against diseases induced by certain Oomycetes, including fungal populations that are resistant to other products. In several ways, this fungicide illustrates the opportunities and challenges presented by many modern pesticides. The specific mode of action, which affects cell wall formation, is associated with a very high level of performance and low dose rates under field conditions. These low dose rates, combined with a low level of toxicity to non-target organisms present an outstanding safety profile. This same highly-specific mode of action, however, limits the spectrum of activity and suggests the need for a resistance management plan, both of which must be addressed in new product development. In addition, the biological and physiochemical properties of this, and other new products are not adequately described by the traditional classification of fungicides into“protectant”and“systemic”types. These unique profiles provide novel and useful products for disease control.

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RADIATION SHIELDING EVALUATION OF IP-2 PACKAGES FOR LOW- AND INTERMEDIATE-LEVEL RADIOACTIVE WASTE

  • Kim, Min-Chul;Choi, Jong-Rak;Chung, Sung-Hwan;Ko, Jae-Hoon
    • Nuclear Engineering and Technology
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    • v.40 no.6
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    • pp.511-516
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    • 2008
  • Korea Hydro & Nuclear Power Co., Ltd. (KHNP) developed new IP-2 packages to transport low- and intermediate-level radioactive waste (LILW) steel drums from nuclear power plants to a disposal facility in accordance with IAEA and Korean transport regulations of radioactive material. Radiation shielding evaluation of the packages was carried out to demonstrate compliance with the regulatory requirements for IP-2 packages of radioactive material. Dose rate limits of LILW drums contained in the packages were determined.

Anti-Obesity Effect of Pine Cone (Pinus koraiensis) Supercritical Extract in High-Fat Diet-Induced Obese Mice (고지방식이로 유도한 비만 Mice에서 잣송이 초임계 추출물의 항비만 효과)

  • Lee, Dasom;Lee, Minhee;Kim, Hyesook;Jeong, Tuk-Rai;Yang, Hyun-Pil;Hyun, Heo Seok;Lee, Jeongmin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.12
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    • pp.1701-1707
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    • 2016
  • The present study investigated the anti-obesity effect of pine cone (PC, Pinus koraiensis) supercritical extract in high-fat diet (HFD)-induced obese mice. Male C57BL/6J mice were treated with HFD, HFD+catechin, and HFD+PC [two different doses, 20 mg/kg body weight (b.w.) and 100 mg/kg b.w.] in each AIN93G supplement for 8 weeks. Treatment of HFD mice with both low and high doses of PC significantly reduced body weight gain compared to HFD mice. Liver weight of mice was reduced in both the low and high dose PC-supplemented groups (24.19% and 19.83%, respectively). Total adipose tissue weight of mice was reduced in both the low and high dose PC-supplemented groups (45.54% and 62.66%, respectively). Serum total cholesterol, triglyceride, LDL cholesterol, and HDL cholesterol were reduced in the low and high dose PC-supplemented groups, and ratios of HDL cholesterol to LDL cholesterol increased by 94.55% in the high dose PC-supplemented group. Serum leptin was significantly reduced in the low and high dose PC-supplemented groups (28.14% and 62.72%, respectively). These results were supported by genetic expression of protein and enzymes related to lipid metabolism assessed by real-time PCR. There was significant reduction of lipid regulatory transcription factors such as $PPAR-{\gamma}$, C/EBP, and SREBP and lipid enzymes such as fatty acid synthesis and lipoprotein lipase in the low and high dose PC-supplemented groups. However, there was no statistical difference between low and high dose PC treatments. These results suggest that pine cone supercritical extract supplementation is able to regulate serum lipid profiles by reducing total cholesterol, triglyceride, and LDL cholesterol levels, followed by regulation of expression of lipid metabolic factors, resulting in reduction of weight gain in HFD-induced obese mice.

Consideration on Shielding Effect Based on Apron Wearing During Low-dose I-131 Administration (저용량 I-131 투여시 Apron 착용여부에 따른 차폐효과에 대한 고찰)

  • Kim, Ilsu;Kim, Hosin;Ryu, Hyeonggi;Kang, Yeongjik;Park, Suyoung;Kim, Seungchan;Lee, Guiwon
    • The Korean Journal of Nuclear Medicine Technology
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    • v.20 no.1
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    • pp.32-36
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    • 2016
  • Purpose In nuclear medicine examination, $^{131}I$ is widely used in nuclear medicine examination such as diagnosis, treatment, and others of thyroid cancer and other diseases. $^{131}I$ conducts examination and treatment through emission of ${\gamma}$ ray and ${\beta}^-$ ray. Since $^{131}I$ (364 keV) contains more energy compared to $^{99m}Tc$ (140 keV) although it displays high integrated rate and enables quick discharge through kidney, the objective of this study lies in comparing the difference in exposure dose of $^{131}I$ before and after wearing apron when handling $^{131}I$ with focus on 3 elements of external exposure protection that are distance, time, and shield in order to reduce the exposure to technicians in comparison with $^{99m}Tc$ during the handling and administration process. When wearing apron (in general, Pb 0.5 mm), $^{99m}Tc$ presents shield of over 90% but shielding effect of $^{131}I$ is relatively low as it is of high energy and there may be even more exposure due to influence of scattered ray (secondary) and bremsstrahlung in case of high dose. However, there is no special report or guideline for low dose (74 MBq) high energy thus quantitative analysis on exposure dose of technicians will be conducted based on apron wearing during the handling of $^{131}I$. Materials and Methods With patients who visited Department of Nuclear Medicine of our hospital for low dose $^{131}I$ administration for thyroid cancer and diagnosis for 7 months from Jun 2014 to Dec 2014 as its subject, total 6 pieces of TLD was attached to interior and exterior of apron placed on thyroid, chest, and testicle from preparation to administration. Then, radiation exposure dose from $^{131}I$ examination to administration was measured. Total procedure time was set as within 5 min per person including 3 min of explanation, 1 min of distribution, and 1 min of administration. In regards to TLD location selection, chest at which exposure dose is generally measured and thyroid and testicle with high sensitivity were selected. For preparation, 74 MBq of $^{131}I$ shall be distributed with the use of $2m{\ell}$ syringe and then it shall be distributed after making it into dose of $2m{\ell}$ though dilution with normal saline. When distributing $^{131}I$ and administering it to the patient, $100m{\ell}$ of water shall be put into a cup, distributed $^{131}I$ shall be diluted, and then oral administration to patients shall be conducted with the distance of 1m from the patient. The process of withdrawing $2m{\ell}$ syringe and cup used for oral administration was conducted while wearing apron and TLD. Apron and TLD were stored at storage room without influence of radiation exposure and the exposure dose was measured with request to Seoul Radiology Services. Results With the result of monthly accumulated exposure dose of TLD worn inside and outside of apron placed on thyroid, chest, and testicle during low dose $^{131}I$ examination during the research period divided by number of people, statistics processing was conducted with Wilcoxon Signed Rank Test using SPSS Version. 12.0K. As a result, it was revealed that there was no significant difference since all of thyroid (p = 0.345), chest (p = 0.686), and testicle (p = 0.715) were presented to be p > 0.05. Also, when converting the change in total exposure dose during research period into percentage, it was revealed to be -23.5%, -8.3%, and 19.0% for thyroid, chest, and testicle respectively. Conclusion As a result of conducting Wilcoxon Signed Rank Test, it was revealed that there is no statistically significant difference (p > 0.05). Also, in case of calculating shielding rate with accumulate exposure dose during 7 months, it was revealed that there is irregular change in exposure dose for inside and outside of apron. Although the degree of change seems to be high when it is expressed in percentage, it cannot be considered a big change since the unit of accumulated exposure dose is in decimal points. Therefore, regardless of wearing apron during high energy low dose $^{131}I$ administration, placing certain distance and terminating the administration as soon as possible would be of great assistance in reducing the exposure dose. Although this study restricted $^{131}I$ administration time to be within 5 min per person and distance for oral administration to be 1m, there was a shortcoming to acquire accurate result as there was insufficient number of N for statistics and it could be processed only through non-parametric method. Also, exposure dose per person during lose dose $^{131}I$ administration was measured with accumulated exposure dose using TLD rather than through direct-reading exposure dose thus more accurate result could be acquired when measurement is conducted using electronic dosimeter and pocket dosimeter.

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Usefulness Evaluation of Low-dose CT for Emphysema : Compared with High-resolution CT (폐기종에 대한 저선량 CT의 유용성 평가: 고해상도 CT와 비교)

  • Lee, Won-Jeong
    • Journal of radiological science and technology
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    • v.39 no.3
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    • pp.329-336
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    • 2016
  • The purpose of this study was to evaluate the usefulness of low-dose CT (LDCT) for emphysema compared with high-resolution CT (HRCT). Measurements of radiation dose and noise were repeated 3 times in same exposure condition which was similar with obtaining HRCT and LDCT images. We analysed reading results of 146 subjects. Six images per participants selected for emphysema grading. Emphysema was graded for all 6 zones on the left and right sides of the lungs by the consensus reading of two chest radiologists using a 4-point scale. Between the HRCT and LDCT images, diagnostic differences and agreements for emphysema were analyzed by McNemar's and unweighted kappa tests, and radiation doses and noise by a Mann-Whitney U-test, using the SPSS 19.0 program. Radiation dose from HRCT was significantly higher than that of LDCT, but the noise was significantly lower in HRCT than in LDCT. Diagnostic agreement for emphysema between HRCT and LDCT images was excellent (k-value=0.88). Emphysema grading scores were not significantly different between HRCT and LDCT images for all six lung zones. Emphysema grading scores from LDCT images were significantly correlated with increased scores on HRCT images (r=0.599, p < 0.001). Considering the tradeoff between radiation dose and image noise, LDCT could be used as the gold standard method instead of HRCT for emphysema detection and grading.

Anti-inflammatory Effects of Hongdeung-Tang on Mice with LPS Injected in Vagina (홍등탕(紅藤湯)이 LPS 질내(膣內) 주입(注入) 생쥐에 미치는 항염증(抗炎症)효과)

  • Seo, Ji-Young;Kim, Yoon-Sang;Yun, Jeong-Mun;Lee, Tae-Hui;Lim, Eun-Mee
    • The Journal of Korean Obstetrics and Gynecology
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    • v.18 no.1
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    • pp.81-93
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    • 2005
  • Purpose : There are various oriental medicine therapy of treating Pelvic Inflammatory Disease(PID) in clinics. We made the PID mice model by injection Lipopolysaccharide (LPS) in vagina, and investigate anti-inflammatory effects of Hongdeung-Tang among oral medication, retention enema therapy and herbal-acupuncture treatment. Method : The ICR(20-30g) mice(♀) were used. To examine the occurrence of inflammation, LPS in different concentration was injected into the vagina of the mice, and White Blood Cell(WBC) in blood was counted. To examine anti-inflammatory effects, 6 mice were assigned to each of the normal group, the control group and the sample group. Hongdeung-Tang was medicated in oral and rectal with 1.0g/kg low dose and 3.0g/kg high dose and by herbal acupucture for 5 days, 2 days before LPS injection. After 3days from LPS injection, blood was collected from retro-orbital plexus, and WBC, Interleukin-6(IL-6), Tumor Necrosis Factor-${\alpha}$(TNF-${\alpha}$) in the blood was counted. Result : After LPS injection with each dose, WBC count showed significant increase depending on LPS concentration from $100{\mu}g/kg$, and it was maximized at 3 or 4 days after LPS injection. the Hongdeung-Tang treatment groups, The number of WBC was decreased significantly only in low dose and high dose oral medication, and IL-6 concentration showed significant decrease in oral and rectal medication as well as in herbal acupuncture treatment. TNF-${\alpha}$ concentration was decreased significantly in oral and rectal medication of low dose and high dose. herbal-acupuncture treatment group datas showed reductive tendency. Conclusion : Based on above results, we made the PID mice model by injection LPS in vagina, and demonstrated anti-inflammatory effect of Hongdeung-Tang of oral medication, retention enema therapy and herbal-acupuncture treatment.

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Reduction of Patient Dose in Radiation Therapy for the Brain Tumors by Using 2-Dimensional Vertex or Oblique Vertex Beam Technique

  • Kim, Il-Han;Chie, Eui-Kyu;Park, Charn-Il
    • Journal of Radiation Protection and Research
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    • v.28 no.3
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    • pp.225-231
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    • 2003
  • Up-front irradiation technique as 3-dimensional conformation, or intensity modulation has kept large proportion of brain tumors from being complicated with acute radiation reactions in the normal tissue during or shortly after radiotherapy. For years, we've cannot help but counting on 2-D vertex beam technique to reduce acute reactions in the brain tumor patients because we're not equipped with 3-dimensional planning system. We analyzed its advantages and limitations in the clinical application. From 1998 to 2001, vertex or oblique vertex beams were applied to 35 patients with primary brain tumor and 25 among them were eligible for this analysis. Vertex(V) plans were optimized on the reconstructed coronal planes. As the control, we took the bilateral opposed techniques(BL) otherwise being applied. We compared the volumes included in 105% to 50% isodose lines of each plan. We also measured the radiation dose at various extracranial sites with TLD. With vertex techniques, we reduced the irradiated volumes of contralateral hemisphere and prevented middle ear effusion at contralateral side. But the low dose volume increased outside 100%; the ratio of V to BL in irradiated volume included in 100%, 80%, 50% was 0.55+/-0.10, 0.61+/-0.10, and 1.22+/-0.21, respectively. The hot area within 100% isodose line almost disappeared with vertex plan; the ratio of V to BL in irradiated volume included in 103%, 105%, 108% was 0.14+/-0.14, 0.05./-0.17, 0.00, respectively. The dose distribution within 100% isodose line became more homogeneous; the ratio of volume included in 103% and 105% to 100% was 0.62+/-0.14 and 0.26+/-0.16 in BL whereas was 0.16+/-0.16 and 0.02+/-0.04 in V. With the vertex techniques, extracranial dose increased up to $1{\sim}3%$ of maximum dose in the head and neck region except submandibular area where dose ranged 1 to 21%. From this data, vertex beam technique was quite effective in reduction of unnecessary irradiation to the contralateral hemispheres, integral dose, obtaining dose homogeneity in the clinical target. But it was associated with volume increment of low dose area in the brain and irradiation toward the head and neck region otherwise being not irradiated at all. Thus, this 2-D vertex technique can be a useful quasi-conformal method before getting 3-D apparatus.

Evaluation of Embryotoxic Potential of Olaquindox and Vitamin A in Micromass Culture and in Rats

  • Kang, Hwan-Goo;Ku, Hyun-Ok;Jeong, Sang-Hee;Cho, Joon-Hyoung;Son, Seong-Wan
    • Toxicological Research
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    • v.26 no.3
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    • pp.209-216
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    • 2010
  • Limb bud (LB) and central nerve system (CNS) cells were prepared from 12.5 day old pregnant female Crj:CD (SD) rats and treated with olaquindox and vitamin A. Cytotoxicity and inhibition on differentiation were measured in each cell. Three doses of olaquindox (4, 21 and 100 mgkg), and 0.2 and 75 mg/kg of vitamin A were administered to pregnant rat for 11 days from $6^{th}$ to $16^{th}$ of pregnancy. $IC_{50}$ values of olaquindox for proliferation and differentiation in CNS cell were 22.74 and $28.32\;{\mu}g/ml$ and 79.34 and $23.29\;{\mu}g/ml$ in LB cell and those values of vitamin A were 8.13 and $5.94\;{\mu}g/ml$ in CNS cell and 0.81 and $0.05\;{\mu}g/ml$ in LB cell, respectively. Mean body weights of pregnant rats were decreased at high dose of olaquindox (110 mg/kg) but relative ovary weight, number of corpus lutea, and number of implantation were not changed. Resorption and dead fetus were increased at high dose of olaquindox, and relative ovary weight, the number of corpus lutea and implantation, and sex ratio of male to female were not significantly changed in all dose of olaquindox. Mean fetal and placenta weights were significantly (p < 0.01) decreased in rats of high group. Seven fetuses out of 103 showed external anomaly like bent tail, and 10 out of 114 fetuses showed visceral anomalies at high group. The ossification of sternebrae and metacarpals were significantly (p < 0.01) increased by low and middle dose of olaquindox but it was significantly (p < 0.01) prohibited by high dose of olaquindox. In rats treated with vitamin A, the resorption and dead fetus were increased by high dose. Mean fetal weights were significantly (p < 0.01) increased by low dose but significantly (p < 0.01) decreased by high dose. Thirty four fetuses out of 52 showed external anomaly; bent tail (1), cranioarchschisis (14), exencephaly (14), dome shaped head (22), anophthalmia (15), brcahynathia (10) and others (19). Forty five fetuses out of 52 showed soft tissue anomaly; cleft palate (42/52) and anophthalmia (22/52) by high dose of vitamin A. Sixty one fetuses out of 61 (85.2%) showed skull anomaly; defect of frontal, partial and occipital bone (21/61), defect of palatine bone (52/61) and others (50/61). In summary, we support that vitamin A is strong teratogen based on our micromass and in vivo data, and olaquindox has a weak teratogenic potential in LB cell but not in CNS cell. We provide the in vivo evidence that a high dose of olaquindox could have weak embryotoxic potential in rats.

Subacute toxicity of cis-Malonato[(4R,5R)-4,5-bis(aminomethyl)-2-isopropyl-1,3-dioxolane]platinum(II)(SKI 2053R) in Beagle Dogs (Beagle Dog에서 cis-Malonato[(4R,5R)-4,5-bis(aminomethyl)-2-isopropyl-1,3-dioxolane]platinum(II)(SKI 2053R)의 아급성독성시험에 관한 연구)

  • Lee, Yong-Soon;Kang, Kyung-Sun;Shin, Dong-Jin;Cho, Jae-Jin;Kim, Hyoung-Ook;Kim, Bae-Hwan;Lim, Yoon-Kyu
    • Toxicological Research
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    • v.8 no.2
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    • pp.235-253
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    • 1992
  • A subacute toxicity study of cis-Malonato[(4R,5R)-4,5-bis(aminomethyl)-2-isopropyl-1,3-dioxolane]platinum(II)(SKI 2053R) was carried out to obtain information on its toxicological profiles, and to determine the maximum tolerated dose in beagle dogs. Four groups of beagle dogs (2M and 2F per group, 0,0.5,1.0,2.0mg/kg/day)were given 15 i.v. injections of SKI 2053R. In order to compare the toxic effects of SKI 2053R with those of cisplatin, one group was treated with cisplatin(0.7mg/kg/day)according to the same treatment schedule. The dosing schedule was divided into 3 courses of 5 consecutive days with 23-day dose-free intervals between each course. After completion of the treatments, remaining dogs were necropsied under established guidelines. Three of four dogs in the high dose group and one of four dogs in the middle dose group treated with SKI 2053R died of hypovolemic shock secondary to hemorrhagic and ulcerative enterocolitis. No toxicity-related mortality occurred in the low dose group of SKI 2053R. No survivor was observed in the group of cisplatin. Clinical signs including vomiting, diarrhea, anorexia and loss body weight were apparent in dogs given either cisplatin or high and middle doses of SKI 2053R. Severe thrombocytopenia and leukocytopenia were observed in the high dose group of SKI 2053R and cisplatin-treatment group, while toxicities as bone marrow suppression were reversible. The significant elevation of serum ALP values in group of SKI 2053R(2.0 mg/kg/day and 1.0mg/kg/day) and cisplatin(0.7mg/kg/day)was observed. Slight proteinuria waa observed in high and middle dose level groups of SKI 2053R. In histopathological examinations, pathological alterations of liver, kidney and spleen were noted dose-dependantly in dogs treated with SKI 2053R, and there was no overt sign of toxicity in low dose group of SKI 2053R. Compared to SKI 2053R, more severe durg-related toxicities occurred in dogs treated with cisplatin. It waw estimated that maximum tolerated dose of SKI 2053R in this treatment schedule was 0.5~0.7mg/kg/day. In conclusion, overall toxic potential of SKI 2053R was approximately 3 times lower than that of cisplatin with respect of lethality.

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Dose-Rate Effects Generated from Repair and Regeneration (재생과 증식에 기인하는 선량률 효과)

  • Yi Pon Nyong;Cho Kwan Ho;Marks Richard D.;Kim Jae Ho
    • Radiation Oncology Journal
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    • v.7 no.2
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    • pp.171-183
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    • 1989
  • A general effect for cell proliferation has been incorporated into Roesch's survival equation (Accumulation Model). From this an isoeffect formula for the low dose-rate regimen is obtained. The prediction for total doses equivalent to 60Gy delivered at the constant dose-rate over 7 days agrees well with the dose-time data of Paterson and of Green, when the parameter ratio A/B (${\approx}{\alpha{\mu}}/2{\beta}\;where\;{\mu}$ is the repair rate) is chosen to be 0.7Gy/h. When a constant proliferation rate and known facts of division delay are assumed, an isoeffect relation between low dose-rate treatment and acute dose-rate treatment can be derived. This formula in the regimens where proliferation is negligible predicts exactly the data of Ellis that 8 fractions of 5 Gy/day for 7 days are equivalent to continuously applied 60Gy over 7days, provided the A/B ratio is 0.7 Gy/h and the $\alpha/\beta$ ratio is 4Gy. Overall agreement between the clinical data and the predictions made by the formula at the above parameter values suggests that the biologcal end points used as the tolerance level in the studies by Paterson, Green, and Ellis all agree and they are not entirely the early effects as generally assumed. The absence of dose-rate effects observed in the mouse KHT sarcoma can better be explained in terms of a large value for the A/B ratio. Similarly, the same total dose used independently of the dose-rate to treat head and neck tumors by Pierquin can be justified.

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