• Title/Summary/Keyword: 반응군

Search Result 2,632, Processing Time 0.032 seconds

Kinetics and mechanism of chromate reduction by biotite and pyrite (흑운모 및 황철석에 의한 6가 크롬의 환원 반응속도와 반응기작)

  • 전철민;김재곤;문희수
    • Economic and Environmental Geology
    • /
    • v.36 no.1
    • /
    • pp.39-48
    • /
    • 2003
  • The removal of chromate from aqueous solution using finely ground pyrite and biotite was investigated by batch experiments and the kinetics and the mechanism of chromate reduction were discussed. The chromate reduction by pyrite was about hundred times faster than that by biotite and was also faster at pH 3 than at pH 4. When pyrite was used, more than 90% of initial chromate was reduced within four hours at pH 4 and within 40 min. at pH 3. However, more than 400 hours was taken for the reduction of 90% of initial chromate by biotite. The results indicate that the rate of chromate reduction was strongly depending on the amount of Fe(II) in the minerals and on the dissolution rate of Fe(II) from the minerals. The reduction of chromate at pH 4 resulted in the precipitation of (Cr, Fe)(OH))$_3$$_{ (s)}$, which is believed to have limited the concentrations of dissolved Cr(III) and Fe(III) to less than expected values. When biotite was used, amounts of decreased Fe(II) and reduced Cr(Ⅵ) did not show stoichiometric relationship, which implying there was not only chromate reduction by ferrous ions in the acidic solution but also heterogeneous reduction of ferric ions by the structural ferrous iron in biotite. However, the results from a series of the experiments using Pyrite showed that concentrations of the decreased Fe(II) and the reduced Cr(Ⅵ) were close to the stoichiometric ratio of 3:1. It was because the oxidation of pyrite rapidly created ferrous ions even in oxygenated solutions and the chromate reduction by the ferrous ions was significantly faster than ferrous ion oxygenation.

Effect of Terminalia chebula on Physiological Activity in Mice (가자(Terminalia chebula) 추출물이 마우스의 생리활성에 미치는 영향)

  • 박종옥;이승은
    • Journal of Life Science
    • /
    • v.14 no.1
    • /
    • pp.148-153
    • /
    • 2004
  • In this study, we investigated the effect of water, extract of Terminalia Chebula (TC) on physiological activity in mice. TC water extract showed hemagglutination against several different types of red blood cells. $LD_{50}$ of TC extract was 390 mg/kg (po). Treatment of TC water extract orally administered 200, 300 mg/kg daily for one week. Hepatic cytosolic enzymes, xanthine oxidase and aldehyde oxidase activities were significantly increased comparison with normal group. Treatment of TC water extract increased hepatic malondialdehyde (MDA) formation, and reduced glutathione content. We also found that the decreased activities of glutathione S-transferase and glutathione reductase but was not affected activities of $\gamma$-glutamylcysteine synthetase after treatment of TC water extract. These results suggested that increase of the hepatic lipid peroxide is caused by glutathione reduction.

Morphological Changes of Stomach Tissue on NPO(nil per os) of Rats Treated Single Irradiation (방사선 단일조사가 금식시킨 흰쥐 위에 미치는 형태학적 변화)

  • Kim, Boo-Soon
    • Journal of radiological science and technology
    • /
    • v.21 no.1
    • /
    • pp.69-78
    • /
    • 1998
  • In this study, I examined the morphological influence of radiation on rats stomach tissue, the difference between NPO and CON(contrast) in the rats stomach was measured after a single irradiation to 15 Gy dose, the results follow; In histological observation; focal congestion and epithelial denudation were observed from NPO rats of a day after irradiation. Fibrosis was showed from both of NPO and CON rats of 28day after irradiation, but in it's area, NPO rats have been more wider than CON rats. In PAS reaction; secreted mucin was reacted very weakly from both of NPO and CON rats of 7 days and 14 days after irradiation, whereas CON rats of 28 days after irradiation were reacted like to control rats. On the basis of this results, we know obviously that NPO will be a factor of stomach abnomalities while hospital patients are treated with high-energy irradiation.

  • PDF

Clinical Study of Topotecan as Second-Line Treatment in Small Cell Lung Cancer (소세포폐암의 2차요법으로서의 Topotecan의 치료효과)

  • Kim, Hak-Ryul;Yang, Sei-Hoon;Jeong, Eun-Taik
    • Tuberculosis and Respiratory Diseases
    • /
    • v.52 no.3
    • /
    • pp.230-240
    • /
    • 2002
  • Background : The majority of chemotherapy-treated small cell lung cancers(SCLC) patients eventually recur. Although many patients are in excellent physical condition at the time of recurrence, few drugs or drug combinations are capable of effecting a tumor regression in this setting. Topotecan, a topoisomerase I inhibitor, is one of the more widely studied single afents in SCLC. The aim of this study was to determine the response rate, survival and toxicity of topotecan as a second line traeatment SCLC. Materials and Methods : 19 patients with measurable SCLC, progressive during the first line chemotherapy (9 cases) or recurrent after the first line chemotherpy(10 cases), were enrolled in this study. Topotecan was administered as a 30-minute daily infusion at a dose of 1.5mg/$m^2$ for 5 consecutive days, every 3 weeks. Results : The overall response rate was 26.3%(5/19, CR 2, PR 3, SD 3, PD 11). The median survival was 24 weeks. The response rate and survival were poor in the nonresponders during first chemotherapy, those who were refractory to the first chemotherapy(recurrent within 3 months after completion of first chemotherapy) and extensive disease, but the results were not statistically significant. The toxicities were mainly hematologic and anemia grade III 1/90, leukopenia grade III 6/90 IV 4/90, thrombocytopenia grade III 1/90 IV 1/90, vomiting grade III 1/90 of cycles were occurred. There was no treatment-related deaths due to severe myelosuppression. Conclusion : Topotecan can be an active second line chemotherapeutic agent for treating SCLC.

Effect of Dietary Fats and Tomato on the Immune Functions of BALB/c Mice (식이지방과 토마토가 BALB/c 마우스의 면역활성에 미치는 영향)

  • Lim, Sang-Dong;Han, Chan-Kyu;Sung, Kee-Seung;Kim, Kee-Sung
    • Korean Journal of Food Science and Technology
    • /
    • v.38 no.2
    • /
    • pp.273-278
    • /
    • 2006
  • Effects of dietary fat and tomato on immune functions were investigated using BALB/c mice. Sixty male BALB/c mice weighing 16-17g were divided into two dietary groups. Control group was fed experimental chow (AIN-76 purified diet) supplemented with saturated fat (beef tallow) and unsaturated fat (safflower oil) at 5% level (weight basis), while treatment group was fed chow added with 0.5% (dry matter basis) of tomato (moisture content 95%) for 10 weeks. Organ weights, delayed-type hypersensitivity test, plaque-forming cell test, agglutination test, differential white cell count, and histological examination were performed at 4th, 7th, and 10th week after dietary treatment. Weight of spleen and spleen index of tomato group increased with increasing experimental period. Thymus index of tomato group was significantly higher than that of control group at 7 and 10 weeks (p<0.05). In delayed hypersensitivity test at 4th, 7th, and 10th week after dietary treatment, tomato group showed more significant increase in footpad swelling reaction 24 hr after challenge than control group (p<0.05). In plaque-forming cell test, tomato group fed 7 weeks increased more significantly than control group, while no significant difference was found between two groups at 10 weeks. Agglutination test decreased with increasing experimental period; tomato group at 10 weeks was higher than control group in antibody response to SRBC. In tomato group, Iympocyte percentage was slightly higher than that of control group, and spleen tissue showed active immune reaction caused by severe proliferation of white pulp.

Characteristics of Kawasaki Disease Patients who are Unresponsive to High-dose Intravenous Immunoglobulin Therapy (가와사끼병에서 정맥용 면역글로불린 불응군의 특성)

  • Kook, Dong-Hyuk;Ko, Yong-Min;Lee, Keun-Young;Kim, Dong-Un;Lee, Kyung-Yil;Lee, Joon-Sung
    • Pediatric Infection and Vaccine
    • /
    • v.15 no.2
    • /
    • pp.180-187
    • /
    • 2008
  • Purpose : We wanted to determine the characteristics of patients with Kawasaki disease (KD) who were unresponsive to intravenous immunoglobulin (IVIG). Methods : The patients with KD were divided into two groups: the IVIG responsive group (25 cases) and the IVIG unresponsive group (14 cases). We analyzed various parameters before and after the administration of IVIG, including the complete blood cell count with the differential count (%), the erythrocyte segmentation rate (ESR), the C-reactive protein (CRP) level and the protein and lipid profiles. Results : The IVIG unresponsive group had a prolonged duration of fever and a higher incidence of CAL compared to the IVIG responsive group (P<0.001, respectively). Before IVIG infusion, the neutrophil differential, the ESR and the CRP values were higher (P<0.001), and the total protein and albumin values were lower in the IVIG unresponsive group (P=0.01) compared to the IVIG responsive group. After IVIG infusion, there were no significant changes in the WBC count and CRP levels in the IVIG unresponsive group. The reduction of the HDL-cholesterol levels by IVIG was more significant in the unresponsive group (P=0.02). Conclusion : A more severe and prolonged inflammatory response occurred in the IVIG unresponsive group at an early stage, and this finding can be detected by such inflammatory parameters as the neutrophil count and the CRP and HDL-cholesterol levels after IVIG infusion.

  • PDF

Inhibitory Effect on Delayed-type Hypersensitivity by the Hot Water Extracts from Medicinal Herbs (식용식물 열수 추출물에 의한 지연형 알레르기 반응의 억제효과)

  • Choi, Eun-Mi;Lee, Bong-Ki;Koo, Sung-Ja
    • Korean Journal of Food Science and Technology
    • /
    • v.33 no.1
    • /
    • pp.146-148
    • /
    • 2001
  • In order to investigate the inhibitory effects on the type IV allergy reaction of the hot water extracts (10 mg/20 g body weight) from medicinal herbs (Flos magnoliae, Poncirus trifoliata, Bupleurum falcatum, Scutellaria baicalensis, Schisandra chinensis), delayed type hypersensitivity by 2,4-dinitro-1-fluorobenzene (DNFB) was measured. Scutellaria baicalensis, Schisandra chinensis and Poncirus trifoliata showed inhibitory effects on the delayed type hypersensitivity by DNFB in the 1'st and 2'nd sensitized mice, but Flos magnoliae showed valuable changes only in the 2'nd sensitized mice. Inhibitory effect of Bupleurum falcatum had no statistical significance (p>0.05). According to above results, Scutellaria baicalensis, Schisandra chinensis and Poncirus trifoliata are supposed to be effective as anti-delayed type allergic regimen.

  • PDF

MONOMER RELEASE FROM PIT AND FISSURE SEALANT FOLLOWING BY SURFACE TREATMENT AND CURING TIME (치면열구전색제의 표면처리와 중합시간 증가에 따른 미반응 모노머 용리 평가)

  • Seo, Hyun-Woo
    • Journal of the korean academy of Pediatric Dentistry
    • /
    • v.34 no.1
    • /
    • pp.122-129
    • /
    • 2007
  • The purpose of this study was to evaluate the effects of a various light curing time on the residual monomers released from light-cured dental sealant, and to examine the effectiveness of surface treatment in reducing the oxygen-inhibited layer of light-cured dental sealant($Helioseal^{(R)}$ F, Vivadent, Liechtenstein). Specimens were cured with a halogen light curing unit(XL 3000, 3M, USA) for 20, 40, 60s. Surface treatment of a light-cured dental sealant included no treatment(control group), a 10-seconds exposure to distilled water(Group I), 10-seconds manual application using a cotton pellet wetted with 75% alcohol(Group II), and 10-seconds application of a water/pumice slurry using a rubber cup on a slow-speed handpiece The specimens were eluted in distilled water for 10 minutes. All elutes were analyzed by HPLC for identification and quantitive analysis of monomers. The results of this study can be summarized as follows. 1. None of the chromatograms of the tested sealant displayed peaks with the same retention time as that of the standard solution, except for TEGDMA. 2. The release of TEGDMA decreased with increasing curing time in conventional halogen light. 3. All surface treatment group had a decrease of monomer release in comparison with no treatment group. 4. Treatment that Group III eliminated the greatest amount of any type of residual monomers. 5. The elution of unreacted monomers from curing with halogen curing unit for 60s and Group III was less than other groups.

  • PDF

Effects of Active and Passive Distraction Intervention on Pain Responses of Preschool Children during Immunization (능동적 및 수동적 관심전환 중재가 예방접종 시 학령전기 아동의 통증반응에 미치는 효과)

  • Im, Eun-Seon;Kim, Jin-Sun
    • The Journal of the Korea Contents Association
    • /
    • v.16 no.12
    • /
    • pp.102-112
    • /
    • 2016
  • The purposes of this study were to identify the effects of distraction strategies compared to usual pain management, and to compare the effects of passive and active distraction on pain responses of preschool children during immunization. A quasi experimental with non-equivalent control group posttest design was used. Participants for each group were 30 preschool children who visited a pediatric clinic to have influenza immunization. Children in experimental groups selected one of two distraction types. Pain responses were measured by children, parents, and researcher. Pain responses by children, parents, and researcher during immunization were significantly different between groups. Children in passive or active distraction group were more distracted than children in control group. Moreover, self-reported pain response by children($2.70{\pm}0.88$) and researcher($12.97{\pm}2.39$) in active group were higher than pain scores by children($2.27{\pm}0.64$) and researcher($10.63{\pm}1.65$) in passive group. Results of this study identified that distraction intervention is an effective method for decreasing pain responses in preschool children during immunization. Passive distraction is more effective than active distraction. Use of distraction strategies during immunization should be facilitated. Further research comparing distraction strategies by types and forms is needed.

Psychophysiologic Responses to Event Imagery in Traffic Accident Related Patients (교통사고관련 환자에서 사건상상에 대한 정신생리반응)

  • Chung, Sang-Keun;Choi, Myong-Su;Hwang, Ik-Keun
    • Sleep Medicine and Psychophysiology
    • /
    • v.8 no.1
    • /
    • pp.45-51
    • /
    • 2001
  • Objectives: The experience of traffic accident is a kind of the psychosocial stressors to person. The traffic accident-related patients may show the psychophysiologic hyperarousal. So we examined the differences of psychophysiologic response between patients with and without the memory of experienceing a traffic accident. Methods: Twenty-four traffic accident-related patients were divided into two groups according to ther memory of a traffic accident. In psychological assessment, levels of anxiety and depression were evaluated by State-Trait Anxiety Inventory, Beck's Depression Inventory, and Hamilton Rating Scales For Anxiety and Depression. Heart rate, electrodermal response (EDR), and electromyographic activity (EMG) were measured by biofeedback system, and systolic and diastolic blood pressure by automated vital sign monitor during baseline, task, and rest periods. We utilized script-driven imagery technique as a stressful task. The patients listened to the script describing their own traffic accident experience and were instructed to imagine the event during the task period. Statistically analytic data were obtained from the differences of psychological and psychophysiologic data between two groups. Results: The memory group did not show significantly higher EDR than the none memory group, but showed higher tendency during baseline, imagery, and rest periods. The memory group showed significantly lower EMG than the none memory group during rest period. However, there were no differences in other psychophysiologic reponses between the two groups. Conclusion: Our results showed that the memory group had higher tendency in autonomic arousal level such as electrodermal response than the none memory group. We suggest that physicians need to minimize repetitive imagery of traffic accident (reexperience), and decrease the autonomic hyperarousal in the treatment of traffic accident-related patients.

  • PDF