• 한국임상수의학회지
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• 제10권1호
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• pp.111-130
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• 1993

고양이에서 납의 중독량을 결정하고 행동과 임상병리학적인 변화를 밝히고, 납 투여용량과 혈중 납농도와의 관계를 규명하기 위하여 42마리의 고양이를 대상으로 체중에 따라 0(대조군), 10, 100(저용량), 1000, 2000, 4000(고용량) ppm의 lead acetate를 경구적으로 투여하여 납독성을 평가하였다. 고투여용량(1000, 2000, 4000ppm)을 투여한 어떤 고양이는 분출성 구토, 활동항진 그리고 발작을 보였다. 모든 실험군에서 성장율은 변화가 없었다. 고양이의 정상 혈중 납농도는 사람, 개 그리고 소의 혈중 납농도 보다 낮았다. 고양이에서 준임상형 납중독의 혈중 납농도는 3~20$\mu\textrm{g}$/100$m\ell$이었고, 임상형 납중독의 혈중 납농도는 20~l20$\mu\textrm{g}$/100$m\ell$이었다. Zinc protoporphyrin 농도는 납 투여용량에 비례하였으며 50$\mu\textrm{g}$/100$m\ell$ 이상으로 ZPP농도가 유의성 있게 증가하는 경우는 임상형의 납중독을 의미하였다. Aminolevulinic acid dehydratase는 모든 납 투여용량에 역비례 관계를 보였고, 고양이의 납노출에 대한 유용한 진단적 지표로 나타났다. 오줌의 aminolevulinic acid 농도는 대개 납투여용량에 따라서 증가하지만 측정치는 개체에 따라 다양하였다. 피모의 납농도는 납투여용량에 따라 비례적으로 증가하였다. 최소한 고용량에서 납은 PMN세포와 단핵구의 화학주성을 억제하는 것으로 나타났다. 헤모글로빈, 적혈구, 백혈구, 호중구, 임파구, 단핵구 그리고 호산구에서는 투여용량에 대한 반응이 일정하게 관찰되지 않았고 또한 총단백, 혈장단백, BUN그리고 ALT치에서의 용량에 따른 일정한 변화가 없었다. 망상적혈구수는 대부분의 납투여용량수준에서 유의성 있게 증가하지 않았기 때문에 고양이 납중독의 진단적 가치는 거의 없었다. 신경전달속도의 유의성 있는 변화가 없는 것으로 보아 납섭취로 인한 대상성 탈여(Segmental demyelination)는 없는 것으로 생각된다. 고양이의 치사량은 체중 kg당 60~150mg이었다. 납중독 진단에 신뢰할 수 있는 파라미터는 혈중 납농도, ZPP. ALAD 그리고 피모의 납농도이었다.

• 생물정신의학
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• 제4권2호
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• pp.198-210
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• 1997

To examine the double-faced thymoleptic(antidepressant and antimanic) effects of risperidone in mood disorders, this article reviews the psychotropic-induced mania, thymoleptic effects of antipsychotics, therapeutic effects of risperidone and risperidone(RIS)-induced mania(RIM) in mood disorders, risk factors of RIM, possible neurochemical mechanism of these thymoleptic effects, pathophysiological and clinical significance of thymoleptic effects, and suggestive clinical guideline of RIS in mood disorders. RIS appeared effective for bipolar disorder at a lower dose than that recommended for schizophrenia, especially in the cases of maintenance of mood stabilizers, and gradual titration from low doses. Manic induction/exacerbation can occur by chance during RIS treatment in mood disorders, schizoaffective disorders, and schizophrenias. The possible risk factors for RIM are refractory mood disorder, especially in bipolar I disorder with poor initial response ; refractory schizoaffective disorders, especially in bipolar type with poor initial response ; refractory chronic schizophrenias, especially with initial responses ; psychotic features ; higher initial doses ; rapid titration ; combined therapy with antidepressants in refractory depression ; and RIS monotherapy in mania/hypomania. RIS is a drug that preferentially block 5-HT2 receptors. The effects of low dose are due mainly to the blockade of 5-HT2 receptors. There are more gradual increase in D2 blockade with increasing dose and this D2 blocking properties become apparent at higher doses. This may be related to a modulation of dopaminergic transmission by 5-HT2 antagonism at lower doses with the direct action of RIS on DA receptors coming into play at higher dose. The serotonergic antagonistic effect may be important for its effects on depressive symptoms. This, together with adequate blo-ckade of D2 receptors, may not necessarily lead to destabilization of mood disorder, but rather to more therapeutic effects. Therefore, this dose-receptor affinity relationship with both antidepressant and antimanic effects according to treatment duration can explain a continuum of antidepressant effect, antimanic effect, behavioral stimulation, and manic/hypomanic induction/exacerbation. It was the recognition of a useful psychiatric side effects by a thoughtful observer with fertile minds that led to their ultimate utilization as psychotropic drugs, i.e., phenothiazine, MAOI, TCA, and lithium. And, in vivo pharmacological challenge by novel psychotropics, as a neurochemical probe, with more specific actions is a useful tool to select pharmacologically homogeneous subgroup of the same phenotypical(clinical) condition, to further study the unknown underlying pathogenesis of various mental illnesses. Finally, RIS may be a useful alternative or adjunctive drug for patients with mood disorders without psychotic features or refractory to treatment with standard antipsychotic drugs. The more conservative doses(tirated slowly from 1-3 mg/d) of RIS, and maintenance of mood stabilizer in the cases with risk factors of RIM are recommended in mood disorder.

• Journal of Radiation Protection and Research
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• 제31권2호
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• pp.69-89
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• 2006

Biological mechanisms for ionizing radiation effects are different at low doses than at high doses. Radiation hormesis involves low-dose-induced protection and high-dose-induced harm. The protective component is associated with a reduction in the incidence of cancer below the spontaneous frequency, brought about by activation of defensive and repair processes. The Linear No-Threshold (LNT) hypothesis advocated by the International Commission on Radiological Protection (ICRP) and the Biological Effects of ionizing Radiation (BEIR) Report VII for cancer risk estimations Ignores hormesis and the presence of a threshold. Cancer incidences significantly less than expected have been found in a large number of epidemiological studies including, airline flight personnel, inhabitants of high radiation backgrounds, shipyard workers, nuclear site workers in scores of locations throughout the world, nuclear power utility workers, plutonium workers, military nuclear test site Participants, Japanese A-bomb survivors, residents contaminated by major nuclear accidents, residents of Taiwan living in $^{60}Co$ contaminated buildings, fluoroscopy and mammography patients, radium dial painters, and those exposed to indoor radon. Significantly increased cancer was not found at doses <200 $mSv^*$. Evidence for radiation hormesis was seen in both sexes for acute or chronic exposures, low or high LET radiations, external whole- or partial body exposures, and for internal radionuclides. The ubiquitous nature of the Healthy Worker Effect (HWE)-like responses in cellular, animal and epidemiological studies negates the HWE as an explanation for radiation hormesis. The LNT hypothesis is wrong and does not represent the true nature of the dose-response relationship, since low doses or dose-rates commonly result in thresholds and reduce cancer incidences below the spontaneous rate. Radiation protection organizations should seriously consider the cost and health implications of radiation hormesis.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.187-190
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• 2000

본 연구는 5가지의 발광성 미생물을 이용하여 유해 방사선으로 알려져 있는 ${\gamma}-rays$가 여러가지 cellular stresses 중, 특히 유전자 손상과 생물막 손상을 유발하였는데, 이들의 손상 정도가 총 방사선량과 상관관계가 있음을 발생하는 bioluminescence 로써 확인하였다. 뿐만 아니라, 선량률의 변화를 통하여 방사선으로 인한 유전자 손상 및 일반적인 독성 효과가 큰 영향을 받는 것을 확인하였는데, 선량률 증가에 따라 이들 손상정도가 증가하는 것으로 보아 선량률이 genetic 및 radioprotecion에 심각한 영향을 미치는 것을 확인하였다.

• Journal of Korean Neurosurgical Society
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• 제42권2호
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• pp.92-96
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• 2007

Objective : The authors have speculated that metastatic brain lesions from renal cell carcinoma (RCC) show diverse radiological patterns and tumor responses after Gamma knife surgery (GKS), and have hypothesized that these can be predicted from tumor radiological characteristics. The goal of the current study was to identify the radiological characteristics of RCC brain metastases and the predictors of initial radiosurgical response after GKS. Methods : A retrospective analysis was performed on 48 lesions in 18 patients with RCC brain metastasis treated by GKS. The radiological characteristics of these lesions in magnetic resonance images (MRI) were classified into 3 categories according to enhancement patterns in T1-weighted images and signal intensity characteristics in T2-weighted images. Responses to GKS were analyzed according to these categories, and in addition, other potential predictive factors were also evaluated. Results : MRI findings in the three categories were diverse, though numbers of the lesion were comparable. At 2-month MRI follow-ups after GKS, response rate was 54% and the local tumor control rate 83%. T2 signal intensity was found to be the principal predictive factor of response to GKS, namely negative predictive factor. Other variables such as age, sex, tumor volume, dose, duration from initial diagnosis to GKS, and previous systemic therapies failed to show significant relationships with treatment response by multivariate analysis. Conclusion : Careful evaluation of the radiological characteristics of brain metastases from RCC is important prior to GKS because MRI heterogeneity has predictive value in terms of determining initial tumor response.

• 대한미생물학회지
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• 제20권1호
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• pp.109-113
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• 1985

It was well known that B. pertussis cells possess protective antigen, histamine sensitizing factor, heatstable and labile toxin, hemagglutinin, agglutinogen and the others. Previous reports involving above antigenic properties of B. pertussis have been carried out for several years. However, leucocyte promoting property was not yet investigated. In this report, the results of studies on the leucocytosis, particulary the lymphocytosis, produced in mice by injecting pertussis vaccine were presented. Especially leucocyte promoting property and histamine sensitizing property of B. pertussis vaccine treated at various temperatures were compared. The relationship between the leucocyte promoting property and histamine sensitizing property was investigated. Results were as follows. 1. Although leucocytosis was significantly rised in both 0.5ml injection and 0.1ml injection of pertussis vaccine than in control, at the higher dose (0.5ml injection) an elevation in white cell count was more significant. The leucocyte responce to pertussis vaccine was greater following 0.5 ml injection than following 0.1ml injection. 2. Lymphocytosis was significantly rised in both 0.5ml injection and 0.1ml injection of pertussis vaccine than in control. At higher dose (0.5ml injection), an elevation in lymphocyte count was more significant. 3. Order of elevation in differential leucocyte counts was lymphocyte, polymorphonuclear leucocyte and monocyte. 4. The leucocyte response to pertussis vaccine was 2 fold greater following intravenous injection than following subcutaneous injection. 5. Decrease leucocyte promoting activity and histamine sensitizing activity resulted from exposure to temperature above $56^{\circ}C$. Histamine sensitizing activity of pertussis vaccine treated at various temperatures paralleled leucocyte promoting activity.

• 대한약리학회지
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• 제12권1호
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• pp.31-44
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• 1976

It has been reported that many of the effects of digitalis glycosides could be mediated partly through the central nervous system. In this study the effects of ouabain given directly into the lateral ventricle of the brain on the renal function of the rabbit were investigated. Intraventricular ouabain elicited antidiuresis in doses ranging from 0.1 to $3\;{\mu}g$, exhibiting a rough dose-response relationship, and decreased the renal plasma flow, glomerular filtration rate and urinary excretion of sodium and potassium, concomitant with the decrease of urine flow. These decreases in urine flow, excretory rate of electrolytes significantly correlated with the decrease in renal plasma flow or glomerular filtration rate, suggesting that the antidiuresis might have been induced by the hemodynamic changes. Intravenous ouabain in a dose of $1\;{\mu}g$ did not affect the renal function. Systemic blood pressure as well as cardiac activity was not affected by the intraventricular ouabain. Effects of the intraventricular ouabain on renal function were abolished by the intravenous phentolamine-pretreatment but not affected by intraventricular phentolamine-pretreatment. Neither vasopressin infusion nor hydration did affect the renal effects of intraventricular ouabain. From these observations, it is suggested that the antidiuresis of intraventricular ouabain is induced by the increased sympathetic influence to the kidney.

• Nuclear Engineering and Technology
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• 제56권4호
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• pp.1425-1430
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• 2024

This study develops superheated emulsion detectors that are both sensitive to fast neutrons, and thermal neutrons owing to the exergonic ⁶₃Li(n, α)³₁H capture reaction caused by the ⁶Li-containing compound dispersed throughout the gel-like medium. The experimental research was conducted on two SEDs. One detector was an ordinary Freon-12 detector and the other was a Freon-12 detector containing 3.4 % (by weight) LiCl. In order to investigate the sensitivity of lithium-containing SEDs to thermal neutrons, two types of SEDs were simultaneously exposed to various flux levels of thermal neutrons from ²⁴¹Am-Be neutron source inside a cylindrical tank filled with water. A Boron-lined proportional counter was used to estimate the thermal neutron flux and the relevant MCNP code was developed for flux and dose calculations in the prepared set-up around ²⁴¹Am-Be source. The results demonstrate that there is a proportional relationship between the variations of SED response and the change in thermal neutron flux and dose. Also, the sensitivity of SED was estimated.

• Radiation Oncology Journal
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• 제8권1호
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• pp.73-77
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• 1990

1981년부터 1989년까지 경희대학 부속병원 치료방사선과에서 무기폐를 동반한 폐암으로 방사선 치료를 받은 환자중, 과거력상 폐절제술, 항암요법, 방사선치료등의 기왕력이 있는 환자를 제외한 42명을 대상으로 치료성적을 분석하였다. 1. 비소세포성 폐암은 $62\%$ (21/34), 소세포성 폐암은 $75\%$ (6/8)에서 각각 무기폐가 방사선 치료 후 재팽창 되었으며, 전체 환자의 $64\%$ (27/42)에서 부분 또는 완전반응(reexpansion)을 나타내었다. 2. 방사선 총선량이 40 Gy (1297 ret) 이하와 40 Gy (1337 ret) 이상인 군에서 반응은 각각 $50\%$ (6/12)와 $70\%$ (21/30)이 었으며, 총선량과 무기폐 반응사이에는 유의한 관계가 있었다(p<0.01). 3. 분할조사선량에 따른 반응율은 소선량($180\~200$ cGy)에서는 $53\%$ (14/22), 대선량(300 cGy)에서는 $65\%$ (13/20)이었다. 4. 이상의 성적으로 보아 무기폐를 동반한 폐암 환자중에서, 특히 수술과 항암요법으로 치료가 곤란하고 조속한 처치를 요하는 비소세포성 폐암에서 방사선 치료의 중요한 역할이 확인되었다.

• 한국산업보건학회지
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• 제16권4호
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• pp.398-412
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• 2006

The purpose of this study is to investigate the relationship between the acceleration of vibration by the powered hand tools used in the shipbuilding industry, and to develop the prospective prevalence model for the hand-arm vibration syndrome among the shipbuilding workers.The acceleration levels and frequencies of six types of grinder were measured using the ISO5349 method along with the time of exposure to the vibration from the powered hand tools. Medical examination for 114 workers were performed using the cold provocation test. Comparisons were made between the estimated prevalence of hand-arm vibration syndrome from ISO5349 and the observed values from the medical examinations. By multiple regression, we developed the prospective prevalence model of hand-arm vibration syndrome produced by the hand tools used in the shipbuilding industry. 4 hour-energy-equivalent frequency-weighted accelerations were $6.23m/s^2$ in the grinding job done after welding, and $13.39m/s^2$ in the grinding job done before painting. The mean exposure time while holding powered hand tools was 4.64 hours. Prevalence rates of Raynaud's Phenomenon were 12.04% in the grinding after soldering, and 42.9% in the grinding before painting measured using the ISO5349 method. After exposure to vibration for 10.79 years, about a half of the workers in the grinding after welding could developed Raynaud's Phenomenon. For the workers in the grinding before painting, the latency was 5.02 years. The ISO equation for dose response relationship was not significantly correlated with observed recovery rates of finger skin temperatures, blood flows and amplitudes of nerve conduction velocities. A multiple regression model for dose-response relationship was proposed from the results. Recovery rate of the skin temperatures = -0.668+ 0.337 ${\times}$ 4 hour energy equivalent frequency-weighted accelerations + 0.767 ${\times}$ duration of vibration exposure(years) The validity was proved by multiple regression analysis after correlation transformation and regression results based on model-building data and validation data.