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The Study of Reducing Radiation Exposure Dose and Comparing SUV According to Applied IRIS (Iterative Reconstruction in Image Space) for PET/CT (PET/CT 검사 시 IRIS (Iterative Reconstruction in Image Space) 적용에 따른 CT 피폭선량 감소와 PET SUV 비교 연구)

  • Do, Yong Ho;Song, Ho Jun;Lee, Hyung Jin;Lee, Hong Jae;Kim, Jin Eui
    • The Korean Journal of Nuclear Medicine Technology
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    • v.16 no.2
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    • pp.29-34
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    • 2012
  • Purpose : Presently, hardwares and softwares for reducing radiation exposure are continually developed for PET/CT examination. Purpose of this study is to evaluate effectiveness of reducing radiation exposure dose of CT and SUV changes of PET when applied each kernel to ACCT (Attenuation Correction Computed Tomography) according to adopted IRIS (Iterative Reconstruction in Image Space) software. Materials and Methods : Biograph mCT (Siemens, Germany) was used as a PET/CT scanner. Using AAPM CT performance phantom, from standard (120 kVp, 100 mAs), 7 scans were conducted by reducing 15 mAs each. After image reconstruction by FBP (Filtered Back Projection) and IRIS, noise and spatial resolution were evaluated. The same method was applied to anthropomorphic chest phantom and acquired images were compared. NEMA IEC body phantom was used for SUV evaluation. Injected dose rate for hot sphere (hot) and background cylinder (BKG) were 1:8. CT dose condition (120 kVp, 50 mAs) was the same for each scan and PET scan durations were 1, 2, 3 and 4min. After scanning, each kernel of IRIS was applied to ACCT. And PET images were reconstructed by ACCT adopted IRIS for comparing SUV changes. Results : AAPM phantom test for noise evaluation, SD for FBP 100 mAs, IRIS 55 mAs were 8.8 and 8.9. FBP 85 mAs, IRIS 40 mAs were 9.5 and 9.7. FBP 70 mAs, IRIS 25 mAs were 11.9 and 11.1. Above mAs condition for FBP and IRIS, SD showed similar values. And for spatial resolution test, there was no significant difference. For chest phantom test, when applied the same mAs and kernel to both of FBP and IRIS, every applied kernels showed reduced noise. Lower mAs and higher kernel value showed higher noise reduction. There was no considerable difference only except for I70 very sharp kernel for SUV comparison using NEMA IEC body phantom. Conclusion : In this study, low mAs (55 mAs) applied IRIS and standard mAs (100 mAs) applied FBP showed similar noise. And only except for I70 kernel, there was no significant SUV changes. It is possible to reduce needless radiation exposure and acquire better image quality than FBP's through applying appropriate kernel of IRIS to PET/CT.

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Distribution of Cadminum Fractions in Paddy Soils and Their Relation to Cadmium Content in Brown Rice (답토양중(畓土壤中) Cadmium의 형태별(形態別) 분포(分布)와 현미중(玄米中) Cadmium 함량(含量)과의 관계연구(関係硏究))

  • Lim, Sun-Uk;Kim, Sun-Kwan
    • Korean Journal of Soil Science and Fertilizer
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    • v.16 no.1
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    • pp.28-35
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    • 1983
  • The object of this study was to investigate the distribution of Cd fractions in paddy soils in relation to some soil characteristics and to find out the relationships between soil Cd fractions and Cd content in brown rice. Thirty six soils and rice samples were collected from the paddy field adjacent to zinc mining sites at harvest time in 1981. Total Cd content of brown rice samples was analyzed. A sequential extraction procedure was used to fractionate Cd in soils into the designated forms of exchangeable, adsorbed, organically bonded, carbonate, sulfide, and residual Cd. The results obtained were as follows: 1. The distribution of Cd fractions in soil showed a wide difference depending on soil properties. As an average value it was observed that organically bonded Cd amounted 43.7%; residual Cd, 6.5%; and other fractions, 10-15%. 2. With higher soil pH, organically bonded and carbonate Cd fraction tended to be higher but exchangeable fraction lower. Other forms of Cd showed no difference with soil reaction. 3. Organically bonded fraction was positively correlated with soil organic matter content, while others except adsorbed fraction showed an adverse tendency. 4. The relation of fraction distribution to soil C E C was similar to the case of organic matter. 5. Cadmium content in brown rice showed significant possitive correlation with organically bonded Cd content (r = 0.655) and carbonate, Cd content of soil (r = 0.328) but there was no significant correlation with contents of other forms.

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Treatment of Pectus Carinatum with a Compressive Brace (압박 교정기를 이용한 새가슴의 치료)

  • Son, Jin-Sung;Jeon, Cheol-Woo;Lee, Seong-Jin;Lee, Chol-Sae;Lee, Kihl-Rho;Lee, Seock-Yeol
    • Journal of Chest Surgery
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    • v.40 no.5 s.274
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    • pp.369-375
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    • 2007
  • Background: Patients suffering with pectus carinatum complain of cosmetic problems when they stand and this in spite of wearing cloths. The standard surgical treatment of pectus carinatum is resection of the deformed cartilages, but the wide operative scar, post-operative pain and complications related with such an operation can occur. Therefore, we have peformed compressive brace therapy as a non-operative treatment for pectus carinatum and we observed the effects and the efficiency of this treatment. Material and Method: From January, 2001 to December, 2006, 109 patients wore the compressive brace for all day. The degree of satisfaction was evaluated after $6\sim9$ months of wearing the compressive brace. The degree of satisfaction was evaluated by a score of from $1\sim4$. A score of 1 was assigned when the status was worse, 2 when it was the same, 3 when there was partial improvement and 4 when remarkable improvement was observed. The degree of satisfaction was assessed subjectively by the parent if the patient was a child younger than middle school age, and the patients older than middle school age assessed the score themselves. Result: The mean score of the overall degree of satisfaction was $3.93{\pm}0.33$. Recurrence of pectus carinatum after removal of compressive brace occurred in 6 patients (5.5%) of the total 109 patients. But 4 patients of the total 6 recurred patients stopped wearing of compressive brace against our advice. The 6 recurred patients were re-corrected by re-wearing the compressive brace within 3 months after they originally removed the compressive brace. The complications were discomfort with initially wearing the compressive brace, which occurred in all patients, skin rash due to the compressive brace for 76 patients (69.7%) and skin discolorization with excessive compression for f6 patients (5.5%). The skin rash and discolorization returned to normal within a few months after removal of the compressive brace. Conclusion: This study demonstrated that non-surgical treatment with using the compressive brace for patients with pectus carinatum was effective, and especially for children and teenagers. Non-surgical treatment with using a compressive brace would be helpful for the patients suffering with pectus carinatum and who dislike surgical operations because of their fear about general anesthesia and operation-related complications. Yet long-term follow up is necessary to accurately evaluate the effectiveness of this compressive brace and the recurrences after removal of the compressive brace.

Pressure Drop Predictions Using Multiple Regression Model in Pulse Jet Type Bag Filter Without Venturi (다중회귀모형을 이용한 벤츄리가 없는 충격기류식 여과집진장치 압력손실 예측)

  • Suh, Jeong-Min;Park, Jeong-Ho;Cho, Jae-Hwan;Jin, Kyung-Ho;Jung, Moon-Sub;Yi, Pyong-In;Hong, Sung-Chul;Sivakumar, S.;Choi, Kum-Chan
    • Journal of Environmental Science International
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    • v.23 no.12
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    • pp.2045-2056
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    • 2014
  • In this study, pressure drop was measured in the pulse jet bag filter without venturi on which 16 numbers of filter bags (Ø$140{\times}850{\ell}$) are installed according to operation condition(filtration velocity, inlet dust concentration, pulse pressure, and pulse interval) using coke dust from steel mill. The obtained 180 pressure drop test data were used to predict pressure drop with multiple regression model so that pressure drop data can be used for effective operation condition and as basic data for economical design. The prediction results showed that when filtration velocity was increased by 1%, pressure drop was increased by 2.2% which indicated that filtration velocity among operation condition was attributed on the pressure drop the most. Pressure was dropped by 1.53% when pulse pressure was increased by 1% which also confirmed that pulse pressure was the major factor affecting on the pressure drop next to filtration velocity. Meanwhile, pressure drops were found increased by 0.3% and 0.37%, respectively when inlet dust concentration and pulse interval were increased by 1% implying that the effects of inlet dust concentration and pulse interval were less as compared with those changes of filtration velocity and pulse pressure. Therefore, the larger effect on the pressure drop the pulse jet bag filter was found in the order of filtration velocity($V_f$), pulse pressure($P_p$), inlet dust concentration($C_i$), pulse interval($P_i$). Also, the prediction result of filtration velocity, inlet dust concentration, pulse pressure, and pulse interval which showed the largest effect on the pressure drop indicated that stable operation can be executed with filtration velocity less than 1.5 m/min and inlet dust concentration less than $4g/m^3$. However, it was regarded that pulse pressure and pulse interval need to be adjusted when inlet dust concentration is higher than $4g/m^3$. When filtration velocity and pulse pressure were examined, operation was possible regardless of changes in pulse pressure if filtration velocity was at 1.5 m/min. If filtration velocity was increased to 2 m/min. operation would be possible only when pulse pressure was set at higher than $5.8kgf/cm^2$. Also, the prediction result of pressure drop with filtration velocity and pulse interval showed that operation with pulse interval less than 50 sec. should be carried out under filtration velocity at 1.5 m/min. While, pulse interval should be set at lower than 11 sec. if filtration velocity was set at 2 m/min. Under the conditions of filtration velocity lower than 1 m/min and high pulse pressure higher than $7kgf/cm^2$, though pressure drop would be less, in this case, economic feasibility would be low due to increased in installation and operation cost since scale of dust collection equipment becomes larger and life of filtration bag becomes shortened due to high pulse pressure.

The Study on the Influence of Selection Characteristics of Franchise System, business possibility, Communication, Moral Hazard on Franchisee's Perceived Risk, and Recontracting Intention in the Food Service Franchise Industry (외식 프랜차이저의 사업성, 커뮤니케이션, 모럴해저드가 프랜차이지의 위험지각과 재계약의도에 미치는 영향)

  • Yu, Jong-Pil;Lee, In-Ho
    • Journal of Distribution Research
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    • v.16 no.1
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    • pp.1-27
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    • 2011
  • I. Introduction: This study is to examine the structural relationships among exogenous variable (preliminary and post-support, franchisee's perceived business possibility, communication, moral hazard), the mediated variables(satisfaction, perceived risk, trust) and dependent variable(recontracting intention) in the food service franchise industry context. More specifically, this study has considered some realistic characteristics factors influencing satisfaction, perceived risk and trust between franchisors and franchisees and their further recontracting intention from the perspective of a practical approach. In this study, 437 data has been collected and used for the SPSS and AMOS analysis. The data were analyzed with structural equation modeling. Since the result of the overall model analysis demonstrated a good fit, we could further analyze our data. II. Research Model: This study is to examine the structural relationships among preliminary and post-support by franchisor, franchisee's perceived business possibility, and communication, moral hazard, has on effect on franchisee's satisfaction, perceived risk, trust and recontracting intention in the food service franchise industry context. Hypotheses are as following (Stern & EL-Ansary 1988; Oliver, 1997;Kee & Knox, 1970; Moorman, Deshpande & Zaltman, 1993; Perron, 1998; Zaheer, McEvily, Perrone, 1998). III. Result and Implication: We examined franchisee who have food service stores for samples of this study. The data were analyzed with structural equation modeling using path analysis. The result of the overall model analysis appeared as following: ${\chi}^2$ = 61.578 (d.f.=9, p<0.01), CFI =.990, GFI =.973, AGFI =.863, RMR =.019, RMSEA= .116, NFI = .988, TLI = .959. The findings can be summarized as follows: First, preliminary and post support of franchisor, perceived business possibility and communication positively influence to franchisee's satisfaction. Second, moral hazard of franchisor has negatively influence to franchisee's satisfaction and positively influence to perceived risk. Third, franchisee's satisfaction and trust has positively influence to recontracting intention. Fourth, franchisee's perceived risk has negatively influence to trust and recontracting intention. We can concluded that franchisor's preliminary and post support of franchisor, perceived business possibility and communication may be considered as the important factors influence to franchisee's satisfaction. Moral hazard has become a focused issue in franchise industry. Finally, the managerial implication has been stated as followings: First, in the process of building a systematic industry support franchise system and developing a creative business model, franchisee's stable profitability should be considered as the first important factor. The franchisee's trust to franchise may become a dominant factor that influence the business expansion of franchisor. Second, franchisor should communication with their franchisees and deal with the realistic difficulties faced by them with an effort. Third, the franchisor should achieve a synergy effect by utilizing the win-win strategy. The moral hazard strategy that achieving the profit through franchisee's damage will not be inadvisable to franchisor. Then the long-term oriented development and profitability can be maintained. To do so, the franchise industry may break away from the traditional business structure to improve management transparency and competitiveness on investment and organizational changing management. The conflict between franchisor and franchisee also can be reduced and big success can be achieved in the franchise industry.

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Effect of Extender, Preservation Temperature and Period of liquid Boar Semen on Semen Characteristics and Reproductive Performance (돼지 액상정액의 보존액, 보존온도 및 기간이 정액성상과 번식성적에 미치는 영향)

  • 김인철;이장희;김현종;박창식
    • Korean Journal of Animal Reproduction
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    • v.26 no.1
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    • pp.9-16
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    • 2002
  • This study was carried out to investigate the effects of extenders such as Beltsville thawing solution(BTS), Modena and Androhep, preservation temperature and period of liquid boar semen on semen characteristics and reproductive performance. Boars were raised at Swine Artificial Insemination Center in National Livestock Research Institute, Sunghwan, Chungnam, Korea. This experiment was carried out from 1995 to 2000. The results obtained were summarized as follows. 1. Sperm motility in the samples with Androhep and BTS reduced from day 5 and in the samples with Modena reduced from day 3 of storage. pH or 3 extenders varied from 6.24 to 7.04 during day 1 to 5 of storage. Farrowing rate of sows inseminated with liquid boar semen offended with BTs, Modena and Androhep extenders did not show any differences until day f after semen collection. Sows inseminated with Androhep extender had better farrowing rates (P<0.05) than those with Modena extender at day 1 or 5 after semen collection, but farrowing rates after AI using BTS did not differ compared to those Androhep and Modena. Litter size did not show any differences among the three extenders, but Androhep had the decreased litter size from day i of storage. 2. Motility and normal acrosome of the sperm preserved at 5$^{\circ}C$ did not show any differences until day 4 of storage, but those at 17$^{\circ}C$ changed from day 3 and 4, respectively. Farrowing rate of sows artificially inseminated with liquid boa. semen preserved at 17$^{\circ}C$ had higher, than at 5$^{\circ}C$ (p<0.05), but there was no significant differences in litter size. Farrowing rates and litter size were decreased from day 2 and day 3 of storage at 17$^{\circ}C$, respectively. Farrowing rate of sows inseminated with the preserved semen at 5$^{\circ}C$ did not changed until day 4, but the litter size at 5$^{\circ}C$ was lower than that at 17$^{\circ}C$.

Clinical Experience of Abdominal Aortic Aneurysm (복부 대동맥류 수술의 임상적 고찰)

  • Kwak, Young-Tae;Lim, Sang-Hyun;Lee, Sak;Yoo, Kyung-Jong;Chang, Byung-Chul;Kang, Meyun-Shick;Hong, Yoo-Sun
    • Journal of Chest Surgery
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    • v.36 no.4
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    • pp.261-266
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    • 2003
  • Background: Surgery of abdominal aortic aneurysm revealed high operative mortality. We reviewed our 11-years' experiences of abdominal aortic aneurysm operation and wish to obtain information on the treatment. Material and Method: From Jan. 1990 to Dec. 2000, 48 patients were operated due to abdominal aortic aneurysm in Yonsei Cardiovascular Center Mean age was $62.8{\pm}12.7$ and there were 40 males and 8 females. Among 48 patients, nine patients had ruptured abdominal aortic aneurysm, and mean aneurysm diameter of non-ruptured cases was $8.8{\pm}2.4$cm. Result: There were 6 early deaths, and early mortality was 12.5%. Among 9 patients of preoperative aneurysm rupture, three patients died (33.3%), and among 39 patients of non-ruptured cases, 3 patients died (7.7%). Among preoperative variables, age (p<0.05), preoperative BUN level (p<0.05), and DM (p<0.05) were risk factors of early mortality. Among discharged 42 patients, 40 patients were followed up (f/u rate=95.2%) and mean follow up was $3.6{\pm}0.2$ years. During follow up periods, five patients died (late mortality=11.9%), and Kaplan-Meier survival analysis revealed $81.7{\pm}7.6$% survival rate at five and ten year. Linealized incidence of graft related event was 3.53% per patient-year. Conclusion: Surgical mortality of ruptured abdominal aortic aneurysm was higher than non-ruptured cases; therefore, early resection of the aneurysm can decrease the surgical mortality.

Early and Midterm Results of the Extracardiac Fontan Operation and the Change of Internal Diameter of the Conduit (심외도관 폰탄수술후 중단기 성적 및 심외도관의 내경의 변화)

  • 성시찬;김시호
    • Journal of Chest Surgery
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    • v.35 no.3
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    • pp.177-181
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    • 2002
  • Background: Follow-up studies have shown that although outcomes have improved substantially over time, results of the Fontan operation and its modifications remain suboptimal. In this study, we reviewed our experience with the extracardiac conduit Fontan operation, with a focus early and midterm change of internal diameter of PTFE conduit. Material and Method: Between April 1997 and July 2000 were reviewed. Twelve patients (M:6, F:6, mean age 42.04 $\pm$ 12.43months, mean body weight 13.80$\pm$ 1.94kg) underwent extracardiac conduit Fontan operation with expanded PTFE graft. Mean cardiopulmonary bypass time was 109.7$\pm$26.99minute and mean operation time was 455$\pm$89.51minute. Intraoperative fenestration was performed in 10 patients. The aortic cross clamping was not performed in all patients. Result: There was no early deaths and no postoperative dysrhythmia. Postoperative protein losing enteropathy and prolonged pleural effusion occurred in 1(8.3%) and 4 patients(33.3%). Conduit patency was evaluated by magnetic resonance imaging studies. A 9.84$\pm$3.84% mean reduction in conduit internal diameter and there was no statistical correlation between the change of internal diameter of conduit and the postoperative duration after partial correlation analysis(r=0.019, p=0.955). Conclusion: These results demonstrate that the extracardiac conduit Fontan operation provies good early and midterm results and may reduce the prevalence of late arrhythmia. And there is no correlation between the change of internal diameter of conduit and the postoperative duration after extracardiac conduit Fontan operation with the expanded PTFE graft conduit.

Seasonal sea Level oscillations in the East Sea (Sea of Japan) (동해 해수면의 계절적인 변동에 대하여)

  • OH, IM SANG;RABINOVICH, ALEXANDER B.;PARK, MYOUNG SOOK;MANSUROV, ROALD N.
    • 한국해양학회지
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    • v.28 no.1
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    • pp.1-16
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    • 1993
  • The monthly mean sea levels at 48 stations located at the East and Yellow Seas coasts of Korea, Russia and Japan are processed to investigate seasonal sea level variations. The strong seasonal variations are found to be at the west coast of Korea (42.1 cm in Kunsan), in the region of the Korea strait and near the southern part of Primorye (30-33 cm); the weak ones near the southwestern coast of the Sakhalin Island (10-12 cm). Practically for the whole study area except the southwest Sakhalin, the general picture of the seasonal sea level changes is alike: the mean sea level rises in summer-autumn and falls in winter-spring. The spectral analysis of the records also shows that the seasonal oscillations strongly dominate in the sea level variations, more than 80% or total energy in the southern part of the investigated region and 50-70% in the northern part relate to these oscillations. The annal peak significantly prevails in spectra of the monthly sea levels for the majority of stations, the semiannual peak is also well manifested, but the seasonal peaks of higher order (corresponding to the periods of four and three months) reveal only at some records. The maximal amplitudes of annual component by a least square method are found at the Yellow Sea coast of Korea (20-21 cm) and also near the Japanese coast of the korea Strait (19-19 cm). The semiannual component has the maximal amplitudes (3-4 cm) near the south and southwestern coasts of the Sakhalin Island. The annual range of the sea levels is much weaker here than in the other regions, the relative investment of the seasonal oscillations in total energetic budget is only 35-40%, annual ($A_1$) and semiannual ($A_2$) components have nearly the same amplitude (seasonal factor $F=A_1/A_2=0.9-1.2$). On the basis of the present examination on sea level changes together with the results of Tomizawa et. al.(1984) the whole investigated area may be divided into 10 subregions, 2 of them are related to the Yellow Sea and Western part of the Korea Strait (Y1, Y2), the other ones (E1-E8) to the East Sea.

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Estrogeicity of Genistein and Bisphenol A (콩류식품의 주성분인 Genistein과 식품포장재 및 용기에 사용되는 Bisphenol A의 에스트로젠 효과에 관한 연구)

  • 강경선;이영순;신광순
    • Journal of Food Hygiene and Safety
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    • v.13 no.2
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    • pp.106-111
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    • 1998
  • This study has been focused on both estrogenic and proliferating activity of genistein (GEN) and bisphenol A (BPA). GEN and BPA enhance the proliferation of estrogen-dependent MCF-7 human breast cancer cells at concentrations as low as 100 nM of GEN and 8 ng/ml of BP A achieving similar effect to that of estradiol at 1 nM. Expression of the estrogen responsive gene, pS2 was also induced in MCF-7 cells by treatment with genistein at dose as low as 1 nM and BPA at dose as low as 4 ng/ml. Using 21 day-old ovariectomized nude mice, we examined end-bud formation and mammary gland development after treatment with bisphenol A or genistein. Compared with untreated control, mammary gland development and end-bud formation were significantly increased in mice fed genistein or bisphenol A (p<0.05). Taken together, it is concluded that GEN and BP A can act as an estrogen agonist resulting in cell proliferation and induction of the estrogen responsive pS2 gene in MCF-7 cells in vitro and in athymic mice in vivo, respectively. Therefore, it is suggested that GEN and BP A might modulate human endocrine system and these compounds might be considered as a endocrine modulator at the low levels of doses.

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