• Title/Summary/Keyword: 생물학적 리듬

Search Result 13, Processing Time 0.026 seconds

Photoresponsive properties of the retinohypothalamic tract (망막-시상하부 경로의 광반응 특성)

  • Lee, Bae-Hwan;Watanuki, Shigeki;Yasukouchi, Akira;Morita, Takeshi;Sohn, Jin-Hun
    • Science of Emotion and Sensibility
    • /
    • v.10 no.2
    • /
    • pp.253-261
    • /
    • 2007
  • Light is a synchronizing stimulus to regulate the circadian rhythms and neuroendocrine activities in both humans and animals. The retinohypothalamic tract is involved in the day/night cycle and neuroendocrine activities. In particular, melatonin secretion has been known to be affected by light and correlated with many aspects of health problems. This review introduces the role of the light in the biological rhythm and neuroendocrine activities, its relationship with health problems, and the characteristics of retinohypothalamic tract.

  • PDF

A Limit Cycle Model about the Entrainment of Circadian Rhythm (일주기 리듬 편승과 관련된 한계주기궤도)

  • Choi, Don-Chan
    • Development and Reproduction
    • /
    • v.12 no.1
    • /
    • pp.9-18
    • /
    • 2008
  • All the organisms on the earth are affected by the repeating signals from the ambient environment caused by the movements of the sun and the earth. Their physiological and behavioral activities such as reproduction, functional pathway of various molecules, and developmental stage, are reflected by the cyclicity whether it is daily(circadian) or annual rhythms. An essential function of circadian rhythms is to provide an internal estimate of the external local time, thereby allowing the organism to program its activities so that they occur at an appropriate time in the daily environment. Of many rhythmic patterns, the circadian rhythms are considered in this review, focusing on the limit cycle, which is a model to investigate the entrainment.

  • PDF

Circadian Changes in Pharmacokinetics of Cephradine Administered Orally to Healthy Human Volunteers (건강 지원자에서 세프라딘의 약동학적 생체리듬 변화)

  • Lee, Chong-Ki;Choi, Jun-Shik
    • Korean Journal of Clinical Pharmacy
    • /
    • v.15 no.2
    • /
    • pp.100-104
    • /
    • 2005
  • 건강한지원자에서 세프라딘 250 mg 캡슐을 오전 09:00시와 오후22:00시에 경구투여하여 세프라딘의 약물동태학적 주기변화 (생체리듬)를 검토하였다. 혈장중 세프라딘의 농도는 두 투여시간에서 유의성 있는 차이를 보여주었다. 혈장농도곡선하면적 (AUC)은 오후 때 보다 오전 투여시에 유의성 있게 증가되었으며, 생물학적반감기$(t_{1/2})$는 오후 때 보다 오전 투여시에 더 연장되었다. 전신청소를 $(CL_t)$은 오후 때 보다 오전 투여시 유의성 있게 감소되었다.

  • PDF

Sleep-Wake Cycles in Man (인간의 수면-각성 주기)

  • Kim, Leen
    • Sleep Medicine and Psychophysiology
    • /
    • v.4 no.2
    • /
    • pp.147-155
    • /
    • 1997
  • To assess the reliability of chronobiological models of sleep/wake regulation, it is necerssary that the models predict the data which has been studied in sleep research, and they should be generalized across all ages. To date, many adult human data on such models have accumulated, yet it is evident that a comprehensive theory of the biorhythmic aspects of sleep/wake states has not established. Circadian rhythms such as the time going to bed, sleep onset, slow wave sleep pressure, periodicity of REM sleep, daytime performance, and early evening alertness are resumed everyday. Even in adult humans, sleep is inherently polyphasic. In both the disentrained and entrained states, naps when allowed tend to recur in a temporally lawful manner. The monophasic sleep pattern of most industrial societies therefore appears to be purely of social origin. The endogenous biorhythmic nature of circasemidian sleep tendency is supported by the ubiquity of the phenomenon across all ages. The NREM/REM sleep cycle within sleep with its inherent physiological, endocrine, and neurochemical fluctuations represents the best-documented ultradian sleep rhythms. Also, a daytime ultradian variation in sleepiness with a periodicity similar to nocturnal NREM/REM cycle(BRAC hypothesis) is suggested. This review article provides a brief synoptic review of the evidences for circadian, circasemidian, and ultradian sleep/wake rhythms, and then the authour will suggest the issues which expedite fuller modeling of sleep/wake system, to be further discussed.

  • PDF

Rhythms and Biological Clock (리듬과 생체시계)

  • Choi Donchan
    • Development and Reproduction
    • /
    • v.7 no.1
    • /
    • pp.1-7
    • /
    • 2003
  • Most animals, including human beings, live in a cyclic pattern of lift that is influenced by the ambient changes of environment. The regular changes occurred by rotation of the Earth itself its revolving around the Sun, and the local environment, are reflected by the distinct behavior in the living organisms. These regular changes of environment have been imprinted into the genes within the living organisms through the evolutionary process over a long period of time. The genes are expressed by rhythms during the process of fetal development followed by growth. The environmental modifications ultimately are settled in genes, serving as a biological clock that is located putatively in the hypothalamus. Thus the biological clock governs a large number of rhythms and affects the time of birth and death lift expectancy, behavior, physiology, cell division, biochemical reaction, etc. The rhythms are readjusted to the changes of environmental cues. The biological clock has the great advantage of predicting and preparing the regular changes of environment.

  • PDF

Effects of Cycled Lighting on Circadian Rhythms of Premature Infants (미숙아의 생물학적 리듬에 관한 주기적 빛 조절의 효과)

  • Lee, Seong-Jin;Han, Kyung-Ja;Bang, Kyung-Sook
    • Child Health Nursing Research
    • /
    • v.18 no.2
    • /
    • pp.85-94
    • /
    • 2012
  • Purpose: Instead of a chaotic non circadian environmental approach, continuing regular day-night rhythm in neonatal nurseries may benefit the development of preterm infants. The purpose of this study was to define the effects of cycled lighting on circadian rhythms of premature infants. Methods: The experimental group included 15 preterm infants, and the control group, 15 premature infants in the NICU of a general hospital in Seoul. All infants were between 32 and 37 weeks' postconceptional age. The experimental group infants were provided with cycled lighting before discharge. The incubator or bassinet cover of the experimental group was off between 7 AM and 7 PM, and was covered between 7 PM and 7 AM. Results: There were significant differences in the NNNS score ($p$=.039), and some significant differences in the sleep-activity pattern between the experimental group and the control group, but distinct differences in sleep-activity patterns between the two groups could not be defined. Conclusion: The results of this study suggest that cycled lighting can be helpful in the neurobehavioral development of preterm infants. By modifying the NICU environment to provide a more developmentally supportive milieu, nursing professionals can better meet the infants' physiologic and neurobehavioral needs.

An Ecological Study of the Health Status and Dietary habits of Korean Women in Menopause II. Nutritional Status, Dietary Habits and Food Preference of Korean Women in Menopause (갱년기부인의 건강상태와 식생활에 관한 생태학적 연구 II. 갱년기 여성의 건강, 영양섭취상태, 식습관 및 식품선택구조에 관한 연구)

  • 문수재
    • Journal of the Korean Home Economics Association
    • /
    • v.26 no.1
    • /
    • pp.83-96
    • /
    • 1988
  • 科學의 발전과 經濟의 高度成長으로 食生活의 向上은 人間의 수명을 크게 연장시키고 있다. 韓國에 있어서도 이러한 傾向은 같은 樣相이며 더욱이 보건형태가 차차 변경되어 가고 있다. 女性의 平均수명은 男性보다 길며 近來에 이르러 女性人口의 95%가 閉經을 經驗할 때까지 生存하고 있다고 한다. 이러한 실정임에도 불구하고 우리나라 女性의 閉經年令, 更年期에 處한 婦人들의 건강 및 營養攝取狀態, 食生活 態度등에 關한 情報가 파악되어 있지 않고 있다. 本 硏究는 이 點을 감안하여 우리나라의 中年女性의 건강管理의 指針을 세우기 위하여 생물학적 요인 및 환경적 요인이 閉經年令 및 更年期婦人의 건강狀態와 食行動에 어떠한 영향을 미치는지를 검토하여 보았다. 本 硏究는 1980년 12월에서 1981년 2월까지 3개월간 韓國의 2個의 大都市와 5個의 小都市에 거주하는 40歲에서 60歲까지의 女性을 대상으로 설문지를 통해 다음과 같은 사항을 조사하였다. 조사내용으로 1) 폐경연령, 주거환경, 사회경제적 조건, 체위, 임신횟수, 유산경험의 유무 2) 건강상태, 갱년기 자각증상, 유경시 월경의 순, 불순상태 그리고 3) 영양섭취상태와 식행동 등이다. 本論文은 調査內容 中 第 2 報로 更年期女性의 영양섭취상태와 식생활 행동 그리고 更年期 현상과의 關係를 關例시켜 검토하였다. 간이식품 섭취 사항 조사표를 사용하여 영양소의 섭취상태를 조사한 결과 大都市群은 energy, 지방, thiamin 및 ascorbic acid 의 섭취상태가 그 對照群에 比하여 높은 경향을 나타냈다. 열양 구성비에 대한 검토를 보면 糖質:蛋白質:脂肪(C:P:E)의 比가 64~67%:14%:19%~22%였으며 大都市群은 小都市群에 比해 脂肪에서의 energy섭취가 유의적으로 높았다. 더욱이 사회 경제적 측면으로 보아도 지방섭취는 저소득층에서 낮은 경향을 보여주었다. 更年期女性의 음식에 대한 기호變化의 검토를 통해 관찰한 것에 의하면 閉經者가 未閉經者에 比해 더 많이 食品嗜好의 變化를 경험하고 있다고 지적\ulcorner\ulcorner있다. 37.4%와 28.1%가 각기 기호의 變化를 경험하고 있었으며 이는 兩群間에 有意차가 높음을 보여주었다. 閉經 후 2年頃부터 食品의 嗜好變化를 느끼고 있다고 하는 사람이 많았으며 음식은 기름기 있는 것보다 담백한 것, 肉類보다는 生鮮, 果實, 野菜를 더 선호하는 경향이라고 하였다. 자극성이 있는 것에서 덜 자극성 있는 것을 찾는 경향이었다. 이들의 食品선택구조를 파악하는 것은 그 지역의 특수한 영양문제뿐만 아니라 그들의 영양교육, 더 나아가서는 그 지역의 식량영양정책 수립을 위해 중요한 정보를 제공할 수 있다. 大都市群은 肉類, 卵類, 乳類 및 그 製品등의 선택과 빵이나 butter 등의 食品과 正의 相關性을 나타내고 있었으나(p<0.01) 김치와 같은 韓國의 傳統的 食品의 선택時는 乳類, 果實, 빵과 같은 近代的 感覺의 食品과는 負의 相關性을 나타냈다. 한편 김치는 밥 및 기타 곡류 그리고 서류와는 正 相關性을 시사하였다. 小都市群은 對照群과는 多少 상이한 식품선택 구조를 보이고 있다. 즉 卵類나 乳類를 섭취할 수 있는 사회경제적 조건, 그리고 기호를 갖는 사람들은 서류를 제외한 모든 식품과 正의 相關性을 나타냈다. 어느 群이든 밥과 김치는 높은 相關性을 나타내고 있으며, 이 두 식품은 韓國人의 食生活의 基本이 되고 있으며 이를 土臺로 다른 食品의 선택은 地域的, 社會經濟的, 그리고 個人의 기호에 따라 다르게 나타난다는 것이 시사되었다. 閉經前 後의 更年期라는 것은 30餘年 間의 性 hormone의 周期的分泌에 依한 月周期가 停止하는 時期이며, 內分泌環境의 變化에 依한 生體 리듬의 異常은 各種 更年期증상의 원인이 되고 있다. 有經時의 月經주기의 이상을 경험하는 사람에게 특히 更年期증상中 食慾不振이나 不眠 등의 不平 數가 많았다. 이러한 점으로 미루어 보아 estrogen과 食慾과의 相關性은 높음이 시사되었다. 이는 不眠症과는 연관성이 있으며 性홀몬 分泌의 亂脈은 食事攝取의 리듬을 흐틀어 놓으며 이것이 生體리듬의 變化를 유발한다고 본다.

  • PDF

An Automatic Mobile Cell Counting System for the Analysis of Biological Image (생물학적 영상 분석을 위한 자동 모바일 셀 계수 시스템)

  • Seo, Jaejoon;Chun, Junchul;Lee, Jin-Sung
    • Journal of Internet Computing and Services
    • /
    • v.16 no.1
    • /
    • pp.39-46
    • /
    • 2015
  • This paper presents an automatic method to detect and count the cells from microorganism images based on mobile environments. Cell counting is an important process in the field of biological and pathological image analysis. In the past, cell counting is done manually, which is known as tedious and time consuming process. Moreover, the manual cell counting can lead inconsistent and imprecise results. Therefore, it is necessary to make an automatic method to detect and count cells from biological images to obtain accurate and consistent results. The proposed multi-step cell counting method automatically segments the cells from the image of cultivated microorganism and labels the cells by utilizing topological analysis of the segmented cells. To improve the accuracy of the cell counting, we adopt watershed algorithm in separating agglomerated cells from each other and morphological operation in enhancing the individual cell object from the image. The system is developed by considering the availability in mobile environments. Therefore, the cell images can be obtained by a mobile phone and the processed statistical data of microorganism can be delivered by mobile devices in ubiquitous smart space. From the experiments, by comparing the results between manual and the proposed automatic cell counting we can prove the efficiency of the developed system.

Interpretation of Uranium Bioassay Results with the ICRP Respiratory Track and Biokinetic Model (ICRP 호흡기 및 생체역동학적 모델을 이용한 우라늄 생물분석 결과의 해석)

  • Kim, H.K.;Lee, J.K.
    • Journal of Radiation Protection and Research
    • /
    • v.28 no.1
    • /
    • pp.43-50
    • /
    • 2003
  • This study describes a practical method for interpretation of bioassay results of inhaled uranium to assess the committed effective doses both for chronic and acute intake situations. Organs in the body were represented by a series of mathematical compartments for analysis of the behavior of uranium in the body according to the gastrointestinal track model, respiratory track model and biokinetic model recommended by the ICRP. An analytical solutions of the system of balance equations among the compartments were obtained using the Birchall's algorithm, and the urinary excretion function and the lung retention function of uranium were obtained. An initial or total intakes by intake modes were calculated by applying excretion and retention functions to the urinary uranium concentration and the lung burden measured with a lung counter. The dose coefficients given in ICRP 78 are used to estimate the committed effective doses from the calculated intakes.

Estimation of Haplotype Proportions in Single Necleotide Polymorphism Group Using EM Algorithm (EM 알고리듬을 이용한 단일염기변이 (SNP;SINGLE NUCLEOTIDE POLYMORPHISM)군의 일배체형 (HAPLOTYPE) 비율 추정)

  • 김선우;김종원;이경아
    • The Korean Journal of Applied Statistics
    • /
    • v.16 no.2
    • /
    • pp.195-202
    • /
    • 2003
  • Haplotype analysis in SNP is very useful for the study of complex genetic disease due to low cost and high efficiency comparing to individual analysis of each SNP, and is functionally important in biological view. But, the gametic phase of haplotypes is usually unknown in SNP group, and it is difficult to predict haplotype proportions. In this study, haplotype proportions were estimated using EM algorithm from diploid data of SNP group in solid tumor group and normal group. From these results, linkage disequilibrium among SNPs was analyzed.