• 대한방사선치료학회지
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• 제21권2호
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• pp.67-74
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• 2009

목 적: 전립선암 환자를 대상으로 kV 콘빔CT를 이용한 영상유도방사선치료 시 촬영조건에 따른 인체의 각 장기들에 미치는 흡수선량(absorbed dose)과 유효선량(effective dose)을 비교 평가해 보고자 한다. 대상 및 방법: 환자를 대상으로 직접 실험할 수 없으므로 인체의 구성과 조직이 흡사한 인체 모형 팬텀(Anderson rando Phantom, Alderson Research Laboratories Inc., USA)과 전산화 단층 모의치료기(Lightspeed RT CT, GE, USA)를 이용하여 국제 방사선 방호 위원회(International Commission on Radiological Protection, ICRP)에서 권고된 신체 내 중요 장기들을 묘사하였다. 팬텀 내부의 묘사된 주요 장기에 선량 측정을 위하여 열형광선량계(TLD 100 Lif rods, Harshaw Chemical Co., USA)를 1~8개 삽입한 후 팬텀의 중심을 전립선에 위치시키고, On board imager (OBI) System이 부착된 의료용 선형 가속기(Clinac iX, Varian, USA)를 이용하여 두 가지 촬영모드인 표준모드(Standard-mode, A-mode)와 저선량모드(Low-dose mode, B-mode)에서 kV 콘빔 CT 촬영을 각 3회씩 반복해서 측정하였다. 결 과: 인체 모형 팬텀을 이용하여 전립선암 환자를 대상으로 한 kV 콘빔 CT 촬영을 시행한 결과 전립선, 방광, 직장에 대한 흡수선량은 A-mode인 경우 각각 5.5 cGy/1회, 6.5 cGy/1회, 5.7 cGy/1회, B-mode인 경우 1.1 cGy/1회, 1.3 cGy/1회, 1.2 cGy/1회 결과를 보였다. 각 장기에 대한 조직가중치를 고려한 유효선량은 A-mode와 B-mode에서 19.1 mSv, 4.4 mSv의 결과로 나타났다. kV 콘빔CT 촬영 시 인체에 미치는 유효선량을 측정한 결과, 전립선암 영상유도방사선치료 시 A-mode 콘빔CT는 B-mode 콘빔CT보다 환자가 받는 선량이 약 4배 이상 증가하는 것을 알 수 있었다. 결 론: 그러므로 전립선암 영상유도방사선치료 시 환자가 받는 치료 이외의 선량을 고려했을 때 가능한 B-mode 또는 낮은 촬영 조건을 설정하여 환자가 받는 치료이외선량을 가능한 한 줄일 필요가 있다고 사료된다.

• 원예과학기술지
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• 제19권4호
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• pp.515-520
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• 2001

기내에서 생산하여 저온 저장한 감자품종 대지와 수미 소괴경의 휴면타파에 미치는 저선량 방사선의 효과를 조사하고자 ${\gamma}$선을 0.5-30 Gy 수준으로 조사하여 맹아발생과 맹아생육 및 온실에서의 생육과 수량 등을 조사하였다. 감자 괴경의 맹아율과 생육에 대한 저선량 방사선 효과는 저장기간과 품종에 따라 다르게 나타났다. 대지 품종은 대체로 2-8 Gy에서 빠른 맹아 출현율과 양호한 생육 및 수량을 보였으며, 수미 품종은 대체로 2-4 Gy에서 맹아 출현이 빨랐고 온실에서의 생육 및 수량은 4 Gy에서 양호한 증가 효과를 보였다. 이에 저선량 ${\gamma}$선이 감자의 휴면타파와 생육촉진에 효과가 있음을 확인할 수 있었다.

• 한국환경농학회지
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• 제17권2호
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• pp.156-159
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• 1998

작물 초기생육에 대한 저선량 방사선의 효과를 보고자 벼, 콩, 들깨 종자에 저선량 $^{\gamma}$선을 조사하여 발아율과 초기 생육을 관찰하였다. 저선량 $^{\gamma}$선에 의한 작물의 생육초기 효과는 한정되었으나 작물과 생육특성에 따라 적정 선량은 다르게 나타났다. 벼종자의 발아율은 2Gy조사구에서, 유묘초장과 생체중은 0.5Gy에서 가장 높았으며,대두종자의 발아율과 유모생육은 4Gy에서 가장 양호하였다. 들깨종자의 저선량 $^{\gamma}$선 조사에 의해 생육이 다소 불량하였으나 발아율은 2Gy에서, 유묘초장과 생체중은 1Gy에서 증가효과를 나타내었다.

• The Korean journal of internal medicine
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• 제39권2호
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• pp.338-346
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• 2024

Background/Aims: Systemic lupus erythematosus (SLE) responder index (SRI)-4 response has been achieved with belimumab treatment in patients with moderate disease activity in cornerstone clinical trials and following studies. However, most studies involved patients treated with a mean prednisolone-equivalent dose of approximately 10 mg/d and focused on the steroid-sparing effect of belimumab. We aimed to identify the effect of belimumab in patients with mild-to-moderate SLE who were treated with low-dose or no corticosteroids. Methods: We retrospectively reviewed the electronic medical records of patients treated with belimumab for at least 6 months between May 2021 and June 2022. The primary endpoint was SRI-4 response at 6 months. Results: Thirty-one patients were included (13 low dose- and 18 steroid non-users). The mean age was 39.2 ± 11.4 years, and 90.3% of patients were female. The baseline Safety of Estrogens in Lupus Erythematosus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) score was 6.0 (4.0-9.0). The primary endpoint was achieved in 32.3% (10/31) of patients. Significant improvements in anemia, C4 levels, and SELENA-SLEDAI score were observed during treatment. Univariate analysis showed that the baseline SELENA-SLEDAI and arthritis were significantly associated with SRI-4 response at 6 months, and only the SELENA-SLEDAI remained significant (p = 0.014) in multivariate analysis. Conclusions: This cohort study is the first to report the efficacy of belimumab after minimizing the effect of corticosteroids. Belimumab showed efficacy in improving the SELENA-SLEDAI score, anemia, and low C4 in patients who did not receive corticosteroids or received only low doses.

• Clinical Nutrition Research
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• 제13권3호
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• pp.186-200
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• 2024

Meta-analyses have been conducted with conflicting results on this topic. Due to missing several eligible studies in previous meta-analysis by Lam et al., we conducted an extensive systematic review and dose-response meta-analysis of randomized controlled trials in this regard. A comprehensive search was conducted across various databases, including MEDLINE/PubMed, ISI Web of Knowledge, Scopus, and Google Scholar, until November 2023. Based on the analysis of 33 studies comprising 2,047 individuals, it was found that there was a significant increase in body weight for each 1 g/day increase in omega-3 lipids (standardized MD [SMD], 0.52 kg; 95% confidence interval [CI], 0.31, 0.73; I² = 95%; Grading of Recommendations Assessment, Development and Evaluation [GRADE] = low). Supplementation of omega-3 fatty acids did not yield a statistically significant impact on body mass index (BMI) (SMD, 0.12 kg/m²; 95% CI, -0.02, 0.27; I² = 79%; GRADE = very low), lean body mass (LBM) (SMD, -0.02 kg; 95% CI, -0.43, 0.39; I² = 97%; GRADE = very low), fat mass (SMD, 0.45 kg; 95% CI, -0.25, 1.15; I² = 96%; GRADE = low), and body fat (SMD, 0.30%; 95% CI, -0.90, 1.51; I² = 96%; GRADE = very low). After excluding 2 studies, the findings were significant for BMI. Regarding the results of the dose-response analysis, body weight increased proportionally by increasing the dose of omega-3 supplementation up to 4 g/day. Omega-3 fatty acid supplementation can improve body weight, but not BMI, LBM, fat mass, or body fat in cancer patients; large-scale randomized trials needed for more reliable results.

• Toxicological Research
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• 제6권2호
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• pp.131-142
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• 1990

The selective toxicity of lead was tested in central catecholaminergic nervous system of postnatally lead exposed rats. Three groups of animals were prepared; 1) rats exposed to low dose of lead (0.05%PbAc); 2) rats exposed to high dose of lead(0.2%PbAc); 3) age-matched normal control rats. At2, 4, 6 and 8 weeks of age brain and body weight gain, and lead concentrations in brain tissues were measured. At the same ages tyrosine hydroxylase and Na-K ATPase activities were measured in the 4 brain areas of each animal. Body weight gain was decreased after 6 weeks of age in rats exposed to high dose of lead. Concentrations of lead in whole brain tissues were increased from 0.37 to 0.83 (ng/mg wet tissue) in these animals. in lead exposed rats, tyrosine hydroxylase activities were higher but Na-K ATPase activities were lower than those of age-matched control animals. Brain areas where tyrosine hydroxylase activities were detected without concomitant changes of Na-K ATPase activities were pons-medulla (2 weeks of age) and telencephalon (6 weeks of age) in rats exposed to low dose of lead, and those in rats exposed to high dose of lead were midbrain (4 and 6 weeks of age). These data indicate that catecholaminergic nervous system in the brain areas described above could selectively be affected by lead.

• 전기의세계
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• 제23권5호
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• pp.54-60
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• 1974

Proposals were mode on how to differentiate radiation effects in morphological phases of polyethylene and discussions were developed with the results obtained on a low density polyethylene, SOCAREX, specified by number average molecular weight; overbar Mn=5,400, density; 0.92, and degree of branch; 3.4/100 carbon atom, which was irradiated to Co$^{60}$ .gamma. ray at the dose rate of 0.5 Mrad/hr in ambient temperature under the pressure of 10$^{-5}$ Torr. or 1 atm. respectively. The effect to crystalline phase in possibly deduced from dose dependent variation of relative area between (110) and (200) peaks on X ray diffraction spectrum and that, the effects to amorphous phase can be understood through dose dependent relaxation behaviours of .betha. peak on internal friction characteristics of the specimen. The results obtained thus far indicate that, in crystalline phase, relative crystallinity shows a rather rapid decrease up to 20 Mrad with increasing dose, however, little change of crystallinity can be observed in the region between 20-200 Mrad, and degradation appears to be more predominant than crosslinking up to 60 Mrad. While in amorphous phase the indication also shows that degradation is only predominant up to 20 Mrad. Furthermore several correlations can be seen with amenable explanation between dose dependent behaviours observed in both phases.

• 약학회지
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• 제47권1호
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• pp.52-55
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• 2003

Antidiabetic activities of white ginseng 50％ ethanol extract (WGE) and IH901, an intestinal metabolite of ginsenoside R $b_1$, were compared in multiple low dose streptozotocin (STZ)-induced diabetic rats. WGE or IH901 were coadministered with STZ on Day 1 at dose of 100 and 300 mg or 10 and 30 mg, respectively, and continually administered for 16 days. STZ dissolved in citrate boner was injected intraperitoneally at dose of 20 mg/kg for 5 consecutive days. During the experiment, plasma glucose level and body weight were measured every 4$^{th}$ day. Amount of food and water intake were evaluated once a week and compared between groups. WGE and IH901 both significantly reduced the plasma glucose levels on Day 16 as compared with those of the diabetic control group. In the meantime, amount of food and water intake in WGE-and IH901-treated groups were significantly improved in a dose dependent fashion as compared with those of the diabetic control group. Taken together WGE and IH901 showed the comparable antidiabetic activities at the corresponding doses used in this experiment.

• Progress in Superconductivity
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• 제3권1호
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• pp.36-40
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• 2001

We have studied vortex dynamics in$ Bi_2$$Sr_2$$CaCu_2$O$_{8}$single crystals of unirradiated and irradiated samples by using 100 $\times$ $100\mu\textrm{m}^2$Hall sensor. Doses equivalent magnetic fields are 20 G, 100 G and 1 kG. In the magnetization measurement, a second magnetization peak (SMP) was observed in unirradiated, 20 G dose and 100 G dose samples in contrast to 1 kG dose sample. In the unirradiated sample, the SMP was observed in the range of 18 K ~ 35 K and the amplitude of the SMP decreased with increasing temperature. With increase of the irradiation dose, temperature region and sharpness of the SMP were reduced. In the magnetic relaxation measurement, we observed that the normalized relaxation rate S decreased with increasing the irradiation dose. Our results suggest that the vortex dynamics is not greatly affected by low-density columnar defects.s.

• 대한방사선기술학회지:방사선기술과학
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• 제41권2호
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• pp.115-122
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• 2018

We aims to perform comparative analysis on the dose area and image qualities varying on the slice thickness when using Automatic Exposure Controller (AEC) and manual exposure; thus, it wants to suggest a measure to reduce exposure dose by setting the optimal examination condition for each slice thickness. The method was to set the thickness as Thin, Normal, and Heavy adult and evaluate the dose area, spatial resolution, low contrast resolution, Signal to Noise Ratio (SNR) and Contrast to Noise Ratio (CNR) according to each slice thickness by using the AEC and the manual exposure controller. The dose area according to each slice thickness all increased both when using the AEC and the manual exposure. However, the manual exposure showed lower dose area product than the AEC. Spatial resolutions and low contrast resolutions were all observed to be higher than the evaluation standard. Also, the SNR and CNR of each thickness all increased when using the AEC. When using the manual exposure, SNR and CNR increased in all cases other than the Heavy Adult. Consequently, the Thin and Normal Adult showed dose reduction about 2 times when using the manual exposure controller, while ensuring the image quality. Heavy adult was able to maintain good image quality by using AEC.