• 제목/요약/키워드: Dose-response

검색결과 2,332건 처리시간 0.029초

Effects of Ionizing Radiation on Plants and the Radiological Protection of the Environment

  • Stanislav A. Geras'kin;Kim, Jin-Kyu
    • 환경생물
    • /
    • 제21권4호
    • /
    • pp.321-327
    • /
    • 2003
  • Differences between the principles for the radiological protection of man and the environment are compared. The derived levels of exposure for man and biota recommended by the international agencies with dose rates for chronic radiation producing effects at different levels of biological organization were given in terms of the biological effects. Cytogenetic effects on plants after an exposure to ionizing radiation at low doses alone and in combination with other factors are discussed. A wide range of experimental data were analysed and the general conclusions were extracted to cover the topics such as non-linearity of dose response, synergistic and antagonistic effects of the combined exposure of different factors, radiation-induced genomic instability, and the phenomena of radioadaptation.

Treatment of Drug Susceptible Pulmonary Tuberculosis

  • Shin, Hong-Joon;Kwon, Yong-Soo
    • Tuberculosis and Respiratory Diseases
    • /
    • 제78권3호
    • /
    • pp.161-167
    • /
    • 2015
  • Tuberculosis (TB) remains a major global health problem, and the incidence of TB cases has not significantly decreased over the past decade in Korea. The standard short course regimen is highly effective against TB, but requires multiple TB-specific drugs and a long treatment duration. Recent studies using late-generation fluoroquinolones and/or high-dose rifapentine-containing regimens to shorten the duration of TB treatment showed negative results. Extending the treatment duration may be considered in patients with cavitation on the initial chest radiograph and positivity in sputum culture at 2 months of treatment for preventing TB relapse. Current evidence does not support the use of fixed-dose combinations compared to separate drugs for the purpose of improving treatment outcomes. All patients receiving TB treatment should be monitored regularly for response to therapy, facilitation of treatment completion, and management of adverse drug reactions. Mild adverse effects can be managed with symptomatic therapy and changing the timing of the drug administration, but severe adverse effects require a discontinuation of the offending drugs.

카드뮴독성을 평가하기 위한 방법으로서의 염색체 이상 및 자매염색체 교환 (Chromosome Aberration and Sister Chromatid Exchange for the Assessment of Cadmium Toxicity)

  • 맹승희;정해원
    • 한국환경보건학회지
    • /
    • 제17권1호
    • /
    • pp.110-119
    • /
    • 1991
  • This study was performed to investigate the applicability of 9 chromosome aberration and sister chromatid exchange analysis for the assessment of cytotoxicity and cytogenetic effects of cadmium. Induction of chromosome aberration and sister chromatid exchange in CHO-K1 cells and human peripheral lymphocytes by 2 hour-treatment of CdCl$_{2}$ with various concentrations was observed in relation to their frequencies and types of aberration. The frequency of chromosome aberration in CHO cells treated with CdCl$+{2}$ at G$_{1}$ was increased with dose-dependent manner. When human peripheral lymphocytes were treated with cadmium at G0 and harvested at 72 hours there after, the response was dose-dependent and all the aberrations were also chromatid types. There was no significant increase in frequencies of sister chromatid exchange in both CHO cells and human lymphocytes treated with different concentrations of cadmium. It was suggested that SCE analysis was not a good assessment method for cadmium toxicity.

  • PDF

반복 충격에 대한 인체 영향 평가의 새로운 방안 (New Approach to Evaluating the Effects of Repeated Shocks Exposed to Human)

  • 정완섭;권휴상
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2001년도 춘계학술대회논문집
    • /
    • pp.1088-1093
    • /
    • 2001
  • This paper introduces new approaches attempted to evaluate quantitatively the effects of repeated shocks exposed to human. This attempt, by the members of ISO TC 108 / CS4, has been made to add a standardised draft of ISO 2631 Part 1 which covers newly the human response to repeated shocks. It contains the review of previous work related to shocks responses to human and suggests a mathematical model to predict the three-axis lumbar spine accelerations from the measured seat accelerations. The predicted accelerations are used to evaluate the vibration dose to the spine. The evaluated dose values are shown to enable the assessment of adverse health effects.

  • PDF

백서 유방암의 단일 및 분할 조사시 방사선치료 효과 (Single and Fractionated Irradiation of Mammary Tumor of Rat)

  • 하성환;허승재;박찬일
    • Radiation Oncology Journal
    • /
    • 제2권2호
    • /
    • pp.173-175
    • /
    • 1984
  • The therapeutic effect of mammary breast cancer of rat (Sprague Dawley) was estimated by single and 5 fractionated irradiation of $Co^{60}-\gamma-ray$. Response rates over 50a were 20, 43, 67, $80\%$ respectively by single dose irradiation of 800, 1,200, 1,600, 2,000 rad, and 20,38, 57, $88\%$ by 5 fractionated irradiation of 1,400, 2,100, 2,800, 3,500 rad. $50\%$ tumor control dose$(TCD_{50})$ were 1,282rad, 2,312rad respectively with single and fractionated irradiation.

  • PDF

Conjugated Linoleic Acid Negatively Regulates TR4 Activity in 3T3-L1 Adipocytes

  • Choi, Ho-Jung;Kim, Eung-Seok
    • 한국축산식품학회지
    • /
    • 제31권3호
    • /
    • pp.381-388
    • /
    • 2011
  • Dietary conjugated linoleic acid (CLA) play key roles in lipid metabolism. Here, we investigated the effect of CLA on the transcriptional activity of TR4, an orphan nuclear receptor that plays an important role in lipid homeostasis. CLA increased TR4 gene mRNA level in 3T3-L1 adipocytes, but inhibited TR4 transcriptional activity in a dose-dependent manner. TR4 induced perilipin expression in 3T3-L1 adipocytes by activating perilipin promoter activity. In a gel shift assay, TR4 bound direct to the putative TR4 response element in the perilipin promoter. Interestingly, CLA reduced the interaction between TR4 and consensus DR1, a well-known TR4 binding site. Additionally, CLA inhibited TR4-induced perilipin promoter activity in a dose-dependent manner. Together, our results suggest that CLA may play a role in lipid homeostasis in adipocytes by functionally regulating TR4.

식물의 생물학적 시스템에 대한 방사선의 상호작용 (Effect of Irradiation on the Biological System in Plants)

  • 최종일;김진규
    • Journal of Plant Biotechnology
    • /
    • 제40권3호
    • /
    • pp.111-124
    • /
    • 2013
  • Research on the basic interaction of radiation with biological systems has contributed to human society through various applications in pharmaceutical, medicine, agriculture and other technological developments. In the agricultural sciences and food technology sectors, the last few decades have witnessed a large number of pertinent works regarding the utilization of radiation for evolution of superior varieties of agricultural crops of economic importance. This review presents general information about the effect of radiation on plant specificity, dose response, and benefits. There has been summarized of the effects observed after exposure and influenced by several factors including plant characteristics and radiation features. We also report on the effect of ${\gamma}$-irradiations on plants, focusing on metabolic alterations, modifications of growth and development and changes in biochemical pathways.

Benorylate와 Ethoxybenzamide 밍 Lorazepam 과의 상호작용 (Benorylate Interaction with Ethoxybenzamide and Lorazepam)

  • 허인회;이명환
    • 약학회지
    • /
    • 제23권1호
    • /
    • pp.11-16
    • /
    • 1979
  • Benorylate and ethoxybenzamide have been used alone or in combination as an analgesic, antipyretic and antiinflammatory agent. We investigated the significance of the differences of analgesic activities between single and concurrent administration of benorylate and ethoxybenzamide and lorazepam in mice and also antipyretic activity between single and concurrent administration of benorylate and ethoxybenzamide in rats. 1). Concurrent administration of each half dose of benorylate and ethoxybenamide showed much inhibiting effect on the acetic acid-induced writhing syndrome of mice than the above drug alone, and the some increased analgesic response by hot plate method. 2). The synergistic and analgesic effect of combined administration of benorylate and lorazepam was found to be significant. 3). Antipyretic effect of half-dose combined administration of benorylate and ethoxybenzamide on the rat pyrexia induced by yeast(s.c.) and T.T.G. (i.v.) was shown to be similar to the effect of each drug.

  • PDF

Cardiovascular Actions of Daucus carota

  • Gilani, A.H.;Shaheen, F.;Saeed, S.A.
    • Archives of Pharmacal Research
    • /
    • 제17권3호
    • /
    • pp.150-153
    • /
    • 1994
  • Ethanolic extract of Daucus carota (DC) at the dose of 10-100 mg/kg caused a dose-dependent fall in systolic and diastolic arterial blood pressure in nomotensive anesthetized rats. These effects were not blocked by atropine (1 mg/kg) and pretratment with DC did not alter the pressor response to norepinephrine indicating that cardiovascular effects of DC are independent of cholinergic or adrenergic recptors involvement. In spontaneously beating guinea-pig paired atria, DC induced a concentration-dependent (03-5 mg/ml) decrease in force and rate of atrial contractions. In rabbit thoracic aorta, DC caused inhibition of $K^+$-induced contractions at similar concentrations. These results suggest that the extract may exhibit $Ca^{2+}$ channel blocking-like direct relaxant action on cardiac and smooth muscle preperations and this action may be responsible for its hypotensive effect observed in the in vivo studies.

  • PDF