• 제목/요약/키워드: Tissue distribution

검색결과 958건 처리시간 0.045초

Evaluation of dose distribution from 12C ion in radiation therapy by FLUKA code

  • Soltani-Nabipour, Jamshid;Khorshidi, Abdollah;Shojai, Faezeh;Khorami, Khazar
    • Nuclear Engineering and Technology
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    • 제52권10호
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    • pp.2410-2414
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    • 2020
  • Heavy ions have a high potential for destroying deep tumors that carry the highest dose at the peak of Bragg. The peak caused by a single-energy carbon beam is too narrow, which requires special measures for improvement. Here, carbon-12 (12C) ion with different energies has been used as a source for calculating the dose distribution in the water phantom, soft tissue and bone by the code of Monte Carlobased FLUKA code. By increasing the energy of the initial beam, the amount of absorbed dose at Bragg peak in all three targets decreased, but the trend for this reduction was less severe in bone. While the maximum absorbed dose per bone-mass unit in energy of 200 MeV/u was about 30% less than the maximum absorbed dose per unit mass of water or soft tissue, it was merely 2.4% less than soft tissue in 400 MeV/u. The simulation result showed a good agreement with experimental data at GSI Darmstadt facility of biophysics group by 0.15 cm average accuracy in Bragg peak positioning. From 200 to 400 MeV/u incident energy, the Bragg peak location increased about 18 cm in soft tissue. Correspondingly, the bone and soft tissue revealed a reduction dose ratio by 2.9 and 1.9. Induced neutrons did not contribute more than 1.8% to the total energy deposited in the water phantom. Also during 12C ion bombardment, secondary fragments showed 76% and 24% of primary 200 and 400 MeV/u, respectively, were present at the Bragg-peak position. The combined treatment of carbon ions with neutron or electron beams may be more effective in local dose delivery and also treating malignant tumors.

레이저 조사후 자기공명영상과 조직학적 소견의 상호일치도 (MAGNETIC RESONANCE IMAGING AND HISTOPATHOLOGIC CORRELATIONS OF FOCAL LESIONS INDUCED BY LASER)

  • 이정구;정필상;정필섭;조정석;김상준
    • 대한기관식도과학회지
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    • 제2권2호
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    • pp.194-199
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    • 1996
  • Laser therapy is becoming an accepted procedure for tissue coagulation and ablation and is especially useful in treating tumors. The laser energy is applied to the tissue of interest through various delivery systems which are introduced percutaneously, via blood vessels, through body openings, or during surgical exposure of the tissue. One of the major obstacles to effective application of lasers has been the lack of reliable method to determine the extent of tissue involvement in real time. Several methods have been proposed for monitoring the tissue response and controlling the laser in real time during laser therapy. Among them, magnetic resonance imaging(MRI) has been introduced to monitor laser-tissue interactions because laser irradiation induces changes not only in the thermal motions of the hydrogen protons within the tissue but also in the distribution and mobility of water and lipids. The buttocks of New Zealand rabbits were treated by KTP and $CO_2$laser(power : 10 watts, exposure time:10 seconds). m images were taken at immediately after lasering, 1 week later, 2 weeks later, and at the same time, tissues were harvested for histopathologic study. We analyzed MR images and histopathologic findigs of laser-treated tissues. The MR images taken immediately after laser treatment showed 3 layer pattern and which was correlated with histopathologic changes. We suggest MRI may become a useful monitoring tools for laser-tissue interaction.

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돼지와 랫트에서 sulfamethazine의 약물동태학 및 조직분포 (Pharmacokinetic profile and tissue distribution of sulfamethazine in pigs and rats)

  • 윤효인;박승춘;오태광;조준형;박종명
    • 대한수의학회지
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    • 제37권2호
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    • pp.291-299
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    • 1997
  • In order to establish optimal dosage schedules and withdrawal times for sulfamethazine(SMZ) in pigs, pharmacokinetic and tissue distribution experiments were conducted in pigs. For comparative purposes, tissue depletion kinetics are also studied in rats. From three pigs administered with SMZ i.v., the pharmacokinetic profile of SMZ in two pigs was adequately described by a one-compartment open model whereas that in one pig was patterned after a two-compartment open model. Volume of distribution(Vd) was 0.48~0.57 L/kg and biological half-life($t_{1/2}$) was 11.8-16.8 h. From three pigs dosed with SMZ p.o., pharmacokinetic profile was explainable with a one-compartment open model. Time to reach maximum SMZ concentration in serum (Tmax) was 2.8 h, 3.2 h and 7.5 h. Elimination half-life was 2.8-7.5 h. The descending order in concentration of SMZ was plsama > kidney > liver > lung > heart > pancreas > spleen > duodenum > ileum > brain > adipsoe tissue from three pigs sacrificed at 5h, 29h and 54h after the administration of SMZ, p.o.. The protein binding of SMZ in pigs was 55.2%($2.5{\mu}g/ml$), 71.5% ($5{\mu}g/kg$) and 71.5%($10{\mu}g/ml$). The mean systemic bioavailability (F) of SMZ p.o. was 49.1 %. Meanwhile the pharmacokinetic profile of SMZ in rats was adequately described by a one-compartment open model. Absorption of SMZ p.o. in the rat was very rapid. In conclusion, the oral optimal dosage regimen of SMZ for pigs was the initial dose of 45.7 mg/kg followed by the maintenance dose of 30.2 mg/kg for high specific pathogens to SMZ. The time to reach below the stipulated residual allowable concentration (0.1 ppm) was calculated 93 h after oral administration of 200 mg/kg recommended by manufactureres.

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초음파 검사 영상의 정량적인 측정 연구를 통한 지방간 분석 (Fatty Liver Analysis through Quantitative Measurement Study of Ultrasonography Images)

  • 천혜리;장현철
    • 한국방사선학회논문지
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    • 제16권7호
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    • pp.927-934
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    • 2022
  • 본 연구는 간 초음파 영상을 활용하여 정량적인 측정 분석을 통해 조직 내 감쇠 지수, 조직 내 산란 분포지수 값 분석과 함께 초음파 영상 소견 간 일치도를 알아보고자 하였다. 2022년 8월부터 2022년 10월까지 지방간이 의심되어 간 초음파 검사 처방을 받은 45명의 환자를 대상으로 간 초음파 검사를 시행하였다. 연구결과, 초음파 영상 소견과 조직 내 감쇠 지수 간 일치도 분석 결과 Kappa 값이 0.82(p<0.05)로 두 검사 방법 간 매우 높은 일치도를 보였다. 또한, 초음파 영상 소견과 조직 내 산란 분포 지수 간 일치도 분석 결과에서도 Kappa 값이 0.642(p<0.05)로 두 검사 방법 간 높은 일치도를 보였다. 지방간 예측 시 간 초음파 소견 및 정량적인 초음파 검사 기법인 조직 내 감쇠 지수, 조직 내 산란 분포 지수를 활용한다면 지방간 환자의 진행 정도를 판단할 때 도움이 될 수 있을 것으로 생각된다.

초생추(初生雛)의 각(各) 장기(臟器)에 있어서 방사성(放射性) 린(燐)$(^{32}P)$의 흡수분포(吸收分布)에 관한 실험적 연구 (The experimental study on the distribution of radioactive phosphorus-32 to several organs in one-day and seven-days old chicks)

  • 정영채;이현자
    • Journal of Nutrition and Health
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    • 제3권2호
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    • pp.101-106
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    • 1970
  • Radioactive Phosphorus $(^{32}P)$ was administered intramuscularlly to the newly hatched chicken in the purpose of determination of the uptake and the distribution, as related to sex and hour differences of the several organs of the bodies. $2\;{\mu}\;of\;^{32}P$ was administered to each chick, and the distribution of 32P was observed in 1 hour and 24 hours after administration. In this experiment 80 heads of chicken were used(40 chicken were one day and 40 chicken were 7 days old) and the results obtained as follows: 1. The tissue showed an uptake rate of $^{32}P$ dose per 100 milligram of tissue in one day old chicken, with the following sequence: Males (1 hour): Femur. Liver. G., Muscle. Testis. Brain (24 hour): Femur, Testis, Gastrocnemius Muscle, Liver, Brain. Female(1 hour): Femur, Liver, Gastronemius Muscle, Ovary, Brain. (24 hour): Femur, Liver, Gastrocnemius Muscle, Ovary, Brain. 2. In 1 hour, the uptake rate of $^{32}P$ of the tissues showed significant difference between the male and the female except the gastrocnemius muscle and the brain in one day old group, but they were no significance except the testis and ovary after 24 hours. 3. The distribution of $^{32}P$ of the tissues exhibited higher in 1 hour than in 24 hours except the femur, the brain of the male and female, the brain and gastrocnemius muscle of the female in one day old group. 4. The tissue showed an uptake rate of $^{32}P$ dose per 100 miligram of tissue in 7days old chicken, with the following sequence: Male (1 hour): femur, liver, gastrocmenius muscle, testis, brain. (24 hour): femur, testis, gastrocmenius muscle, liver, brain. Female(1 hour): femur, liver, gastrocmenius muscle, ovary, brain. (24 hour): femur, ovary, liver, gastrocmenius muscle, brain. 5. The distribution of $^{32}P$ of the tissues showed no significant difference between the male and the female except the testis and ovary after 24 hours in 7 days old chicken group. 6. The distribution of $^{32}P$ the tissues exhibited higher in 1 hour in 24 hours except the femur, the brain of the male and the female, the brain and the ovary of the female in 7 days old chicken group.

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실혈 후 및 혈압상승 후의 소화기 조직 혈액량 및 산소 섭취량 -제 1 편 정맥혈압과 소화기 조직 혈액량- (Gastrointestinal Tissue Blood Volume Affected by Venous Pressure Change)

  • 윤병학;남기용
    • The Korean Journal of Physiology
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    • 제2권1호
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    • pp.9-15
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    • 1968
  • Changes in gastrointestinal tissue blood volume induced by variations of venous pressure between 6 and 40 mmHg were studied in 32 rabbits. Venous pressure lowering was produced by withdrawal of appropriate volume of blood and venous pressure elevation was obtained by partial occlusion of intra-thoracic vena cava inferior. Estimation of regional tissue blood volume was performed by means of regional distribution of injected $Cr^{51}-labeled$ red blood cells. The following results were obtained. 1. At the normal control venous pressure value of 18 mmHg, spleen showed the highest value of tissue blood volume expressed on weight basis, namely, $111{\mu}l/gm$, Liver tissue blood volume was $95\;{\mu}l/gm$, small intestine 24 and stomach $21\;{\mu}l/gm$, respectively. 2. Linear relationships were observed between venous pressure change and gastrointestinal tissue blood volume. The coefficients of correlation were: in spleen r=0.723; in liver r=0.791; in stomach r=0.704, respectively. In small intestine the relationship was less clear and r=0.358. Tissue blood volume of extrabdominal tissue, such as M. gastrocnemius was not influenced by venous pressure change. 3. The highest change in tissue blood volume expressed on weight basis was observed in spleen. The liver tissue showed the next highest change. Change in total tissue blood volume, however, was greatest in liver and next greatest in small intestine. This was interpreted by the fact that total weight of these two organs was much greater than that of spleen. 4. The mechanism that the change in tissue blood volume lies in the venous system which has a great compliance was discussed.

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종양의 온열치료를 위한 마이크로잔 조사장치의 제작과 응용 (Fabrication of Microwave Applicator for Hyperthermia and Thermal Distribution in Tissues)

  • 추성실;이종태;김귀언
    • Radiation Oncology Journal
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    • 제2권1호
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    • pp.11-20
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    • 1984
  • The renewed interest in the use of hyperthermia in cancer therapy is bases on radiobiological and clinical evidence indicated that there may be a significant therapeutic advantage with the use of heat alone or combined with radiation or chemotherapy, There are many methods for generating heat for localized tumor as like radiofrequency, microwave, electromagnetic induction and ultrasound. But it is very difficult to be even thermal dose distribution and stable output of power and then the detection of temperature in tumor is difficult to be precise with thermocouples and semiconductor sensors. We designed the microwave heating generator, dipole antenna applicators and autometic temperature controlled thermocouples for localized hyperthermia on skin and in cavities. 1. The microwave generator with 120 W, 2,450MHz magnetron could be heating up to $40^{\circ}C\~50^{\circ}C\;for\;1\~2$ hours in living tissues. 2. The thermal dose distribution in tissue with microwave was described $42^{\circ}C\~44^{\circ}C$ with in 3 cm depth and $2\~6cm$ diameter area. 3. Skin surface heating applicator with spiral 3 times wave length antenna radiated high Power of microwave. 4, Intracavitary heating applicator with dipole antenna with autometic control temperature sensor kept up continuously constant temperature in tissue. 5. For constant thermal distribution, applied two steps power with 10W microwave after $17\~20W$ during first 10 minutes. 6. The cooling rate by blood flew in living tissue was rised as $10\%$ then meats.

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일선 2개 보건지소의 진료실적 비교 분석 (충남 서산군) (A Comparative Study on Medical Care Services in Two Community Health Sub-centers(Seo San-Gun, Choong Chung Nam-Do))

  • 장일영
    • Journal of Preventive Medicine and Public Health
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    • 제17권1호
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    • pp.121-126
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    • 1984
  • Several detailed aspects of medical care services during one year (Aug 1, $1982{\sim}$July 31, 1983) were compared between two community health sub-centers; one (A) was served by a local clinician, the other (B) by a trainee of preventive medicine. The results were analysed as follows: 1. Total spells of medical services during the same period in 'A' sub-center was 4,087 and that in 'B' 2,347. Medicaid visitors in 'A' was 1,051 (25.7% of the total), that in 'B' was 250 (10.7%). Significant difference was observed. 2. Average number of visits for the same case in 'A' was 2.0, that in 'B' was 1.4. Average duration of service by day for the same case in 'A' was 3.9, that in 'B' 3.0. 3. Average cost of service for a case in 'A' was 6,770 won, that in 'B' 4,230 won. 4. Difference in age distribution of visitors in the two sub-centers was insignificant. $0{\sim}9$ year group was 38.5% of the total. Difference in distribution by sex (between two sub-centers) was minimal. Male utilisers more than female by ca. 10%. 5. Concerning distribution of visitors by month, utilisation in July, August and September was the highest; the sum of them was 32.7% of the total in 'A' and 32.9% in 'B'. 6. Distribution by diagnoses in 'A' in decreasing order of frequency was Respiratory system diseases (26.1%), Digestive system diseases (23.0%), Diseases of skin and subcutaneous tissue (17.4%), Accidents and poisoning (11.5%) and Diseases of musculoskeletal system and connective tissue (5.4%). That in 'B' was Respiratory system diseases (39.0%), Digestive system diseases (23.0%), Diseases of skin and subcutaneous tissue (14.2%), Accidents and poisoning (10.9%) and Infection and parasitic diseases (9.1%). 7. The 10 most frequent diagnoses comprised 68.5% of the total in 'A' and 65.5% in 'B' 8. Utilisation by accessibility to each sub-center was studied. It is shown that the nearer the distance or the easier the accessibility, the more visits to services. The distinct pattern is manifested in the utilisation in 'A'-Myun.

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