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Characterization of Arsenic Adsorption onto Hematite (적철석(Hematite) 표면의 비소 흡착 특성)

  • Kim, Seong Hee;Lee, Woo Chun;Cho, Hyen Goo;Kim, Soon-Oh
    • Journal of the Mineralogical Society of Korea
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    • v.25 no.4
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    • pp.197-210
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    • 2012
  • Hematite has been known to be the most stable form of various iron (oxyhydr)oxides in the surface environments. In this study, its properties as an adsorbent were examined and also adsorption of arsenic onto hematite was characterized as well. The specific surface area of hematite synthesized in our laboratory appeared to be $31.8g\;m^2/g$ and its point of zero salt effect, (PZSE) determined by potentiometric titration was observed 8.5. These features of hematite may contribute to high capacity of arsenic adsorption. From several adsorption experiments undertaken at the identical solution concentrations over pH 2~12, the adsorption of As(III) (arsenite) was greater than that of As(V) (arsenate). As of pH-dependent adsorption patterns, in addition, arsenite adsorption gradually increased until pH 9.2 and then sharply decreased with pH, whereas adsorption of arsenate was greatest at pH 2.0 and steadily decreased with the increasing pH from 2 to 12. The characteristics of these pH-dependent adsorption patterns might be caused by combined effects of the variation in the chemical speciation of arsenic and the surface charge of hematite. The experimental results on adsorption kinetics show that adsorption of both arsenic species onto hematite approached equilibrium within 20 h. Additionally, the pseudo-second-order model was evaluated to be the best fit for the adsorption kinetics of arsenic onto hematite, regardless of arsenic species, and the rate constant of As(V) adsorption was investigated to be larger than that of As(III).

Virus Inactivation during the Manufacture of a Collagen Type I from Bovine Hides (소 가죽 유래 Type I Collagen 생산 공정에서 바이러스 불활화)

  • Bae, Jung Eun;Kim, Chan Kyung;Kim, Sungpo;Yang, Eun Kyung;Kim, In Seop
    • Korean Journal of Microbiology
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    • v.48 no.4
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    • pp.314-318
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    • 2012
  • Most types of collagen used for biomedical applications, such as cell therapy and tissue engineering, are derived from animal tissues. Therefore, special precautions must be taken during the production of these proteins in order to assure against the possibility of the products transmitting infectious diseases to the recipients. The ability to remove and/or inactivate known and potential viral contaminants during the manufacturing process is an ever-increasingly important parameter in assessing the safety of biomedical products. The purpose of this study was to evaluate the efficacies of the 70% ethanol treatment and pepsin treatment at pH 2.0 for the inactivation of bovine viruses during the manufacture of collagen type I from bovine hides. A variety of experimental model viruses for bovine viruses including bovine herpes virus (BHV), bovine viral diarrhea virus (BVDV), bovine parainfluenza 3 virus (BPIV-3), and bovine parvovirus (BPV), were chosen for the evaluation of viral inactivation efficacy. BHV, BVDV, BPIV-3, and BPV were effectively inactivated to undetectable levels within 1 h of 70% ethanol treatment for 24 h, with log reduction factors of ${\geq}5.58$, ${\geq}5.32$, ${\geq}5.11$, and ${\geq}3.42$, respectively. BHV, BVDV, BPIV-3, and BPV were also effectively inactivated to undetectable levels within 5 days of pepsin treatment for 14 days, with the log reduction factors of ${\geq}7.08$, ${\geq}6.60$, ${\geq}5.60$, and ${\geq}3.59$, respectively. The cumulative virus reduction factors of BHV, BVDV, BPIV-3, and BPV were ${\geq}12.66$, ${\geq}11.92$, ${\geq}10.71$, and ${\geq}7.01$. These results indicate that the production process for collagen type I from bovine hides has a sufficient virus-reducing capacity to achieve a high margin of virus safety.

Serum Albumin Concentrations and Clinical Disorders by Gestational Ages in Preterm Babies (미숙아에서 재태 연령에 따른 혈청 알부민치와 임상증상과의 관계)

  • Lee, Mia;Yun, Soo;Lim, Baek Keun;Kim, Jong Soo
    • Clinical and Experimental Pediatrics
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    • v.48 no.2
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    • pp.148-153
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    • 2005
  • Purpose : The aim of this study was to determine the reference ranges of serum albumin levels depending on the gestational ages of preterm infants. We also intended to compare the mean serum albumin levels between groups of preterm infants that did not develop clinical disorders later, and groups that did develop clinical disorders such as respiratory distress syndrome, intraventricular hemorrhage, retinopathy of prematurity, apnea and bronchopulmonary dysplasia. We also examined the significance of serum albumin as a predictor for the development of clinical disorders. Methods : The records of 208 neonates with gestational ages from 23 weeks to 41 weeks were reviewed retrospectively. The mean albumin concentrations with reference ranges by gestational ages were determined. Statistics for each two of group were compared. Logistic regression analysis was used to model odd ratio, and 95 percent confidence interval as a mean of the association between predictors and outcome. Results : Serum albumin levels were at 23-24 weeks gestation was 2.36 g/dL, rising to 3.43 g/dL in full term babies. There were significant mean differences between the clinical groups and control groups for each clinical disorder such as respiratory distress syndrome, intraventricular hemorrhage, retinopathy of prematurity and apnea in premature babies of 30-36 weeks of gestation. Low serum albumin appeared to be associated with increased risks of clinical disorders. Conclusion : The normal serum albumin levels in preterm infants should be defined according to the gestational ages. Lower albumin levels increase the risks of the later development of clinical disorders, which are common in premature infants.

A Follow-Up Study after Discontinuation of Antiepileptic Drug Therapy in Children with Well-Controlled Epilepsy : The Factors that Influence Recurrence (항전간제로 조절된 간질 환아에서 약물 중지 후 추적 관찰 - 재발위험인자)

  • Chung, Sa Jun;Chung, Hye Jeon;Choi, Young Mi;Cho, Eu Hyun
    • Clinical and Experimental Pediatrics
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    • v.45 no.12
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    • pp.1559-1570
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    • 2002
  • Purpose : There has been no exact answer to the question of when to discontinue antiepileptic drugs(AEDs) in children with well-controlled epilepsy for a long period. This study is about the risk factors of relapse after withdrawal of AEDs in seizure(Sz)-free patients to show a guideline for discontinuation of AEDs. Methods : One hundred and sixty-nine children were diagnosed as epileptic at the Pediatric Dept. of Kyung-Hee Univ. between 1993 to 1998, in whom AEDs had been withdrawn after at least two years of Sz-free period. Univariate analysis using Kaplan-Meier survival analysis and multivariate analysis using Cox-proportional hazard model were performed for sixteen risk factors. Results : Forty-nine of the 169 patients(28.9%) had recurrence of Szs. The mean follow-up after withdrawal of AEDs was 4.1 years, mean treatment period was 4.1 years, and the mean Sz-free period was 3.3 years. Factors associated with an increased risk of relapse were young age at onset, symptomatic Sz, Sz type in West and Lennox-Gastaut syndrome, neurologic deficit, longer Sz-controlling period, shorter total treatment period, number of AEDs used(more than one drug), age at withdrawal of AEDs, and Sz-free period less than two years in univariate analysis using Kaplan-Meier mothod. From multivariate analysis, the factors indicating a significantly higher relapse risk were pre-treatment period after first Sz attack, Sz-controlling period, Sz-free period, number of AEDs used, neurologic abnormalities. Conclusion : For epileptic children who were Sz-free for more than two years, and were more than six-years-old, the discontinuation of AEDs should be considered positively, according to age of onset, Sz type, age at withdrawal of AEDs, total treatment period, Sz-controlling period, number of AEDs used, etiology, neurologic deficit, and the wishes of the patients and the their parents.

The Morphologic Changes of Parvalbumin- Immunoreactive Interneurons of the Dentate Gyrus in Kainate-Treated Mouse Hippocampal Slice Culture Epilepsy Model (Kainic Acid로 처리한 해마박편배양 마우스 간질모델에서 치아이랑 Parvalbumin 면역 반응성 사이신경세포의 형태학적 변화)

  • Chung, Hee Sun;Shin, Mi-Young;Kim, Young-Hoon;Lee, In-Goo;Whang, Kyung-Tai;Kim, Myung-Suk
    • Clinical and Experimental Pediatrics
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    • v.45 no.12
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    • pp.1551-1558
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    • 2002
  • Purpose : Loss of hippocampal interneurons in dentate gyrus has been reported in patients with severe temporal lobe epilepsy and in animals treated with kainic acid(KA). Interneurons contain $Ca^{2+}$- binding protein parvalbumin(PV). The effects of kainic acid on parvalbumin-immunoreactive (PV-IR) interneurons in dentate gyrus were investigated in organotypic hippocampal slice cultures. Methods : Cultured hippocampal slices from postnatal day nine C57/BL6 mice were exposed to $10{\mu}M$ KA, and were observed at 0, 8, 24, 48, 72 hours after a one hour KA exposure. Neuronal injury was determined by morphologic changes of PV-IR interneuron in dentate gyrus. Results : Transient(1 hour) exposure of hippocampal explant cultures to KA produced marked varicosities in dendrites of PV-IR interneuron in dentate gyrus and the shaft of interbeaded dendrite is often much thinner than those in control. The presence of varicosities in dendrites was reversible with KA washout. The dendrites of KA treated explants were no longer beaded at 8, 24, 48 and 72 hours after KA exposure. The number of cells in PV-IR interneurons in dentate gyrus was decreased at 0, 8 hours after exposure. But there was no significant difference in 24, 48 and 72 hours recovery group compared with control group. Conclusion : The results suggested that loss of PV-IR interneurons in dentate gyrus is transient, and is not accompanied by PV-IR interneuronal cell death.

Effect of X-Irradiation on the Levels of some Sulfhydryl Groups, Protein and Cell Volume of Ehrlich Ascites Tumour Cells (X-선(線) 조사(照射)가 Ehrlich 암세포(癌細胞)의 용적(容積), 단백양(蛋白量) 및 수종(數種) Sulfhydryl 기(基)에 미치는 영향(影響)에 관(關)하여)

  • Yu, Choon-Shik;Choo, Young-Eun
    • The Korean Journal of Physiology
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    • v.3 no.2
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    • pp.9-16
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    • 1969
  • It is well known that a number of -SH and -SS containing substances afford a certain measure of protection against radiation effects in many biological systems, and it is conceivable that inherent -SH levels in Ehrlich ascites tumour (ELD)cells may be of decisive improtance with respect to the development of cellular radiation injury. So far, little effort has been directed to elucidate the changes in levels of different -SH and -SS groups in ELD cells when the tumour-bearing whole animal was subjected to the sublethal dose of X-irradiation. The present study was designed to bring some lights in the possible changes of and relationship between various sulfhydryl levels, such as P-SH, NP-SH and NP-SS, as well as the content of protein and cell volume of ELD cells, after subjecting the ELD mice to 1,200 r of X-irradiation. The animals used in this experiment were all mixed bred mice of $20{\sim}25\;gm$ in body weight (approximately 2 months old) irrespective of sex. 12 mice in one experiment were inoculated intraperitoneally with 0.2 ml of ascites tumour cells $(2{\times}10^6\;cells)$, and on the 7th day of the tumour growth, they were X-irradiated with 1,200 r, using the conventional X-ray machine under the following conditions: 200 Kv at 15 mA, 0.5 mm Cu filter, target-skin distance: 50 cm. Radiation dose was measured with the the Philip integrating dosimeter. At 24, 36, 48 and 60 hours after the X-irradiation, the mice were killed by cervical dislocation, and the tumours were taken out. Freshly withdrawn ascites tumours were placed in ice, and immediately the cell concentration was measured with the Coulter Cell Counter (Model B), and the hematocrit of the tumour cells were also determined. Cell volume was thus calculated by the cell concentration and hematocrit value. P-SH content of ELD cells was measured potentiometrically according to the method of Calcutt & Doxey, and NP-SH and NP-SS contents were measured spectrophotometrically by the method described by Ellman. Protein content of ELD cells was determined with the Folin phenol reagent by Lowry et al. Altogether, 48 experimental mice were used, and 12 mice with the only exception of X-irradiation were used as the control. Results obtained indicate that the contents of all the cellular sulfhydryl groups as well as cell volume and protein content of the ELD cells increase significantly as time progresses after the sub-lethal X-ray dose of 1,200 r was given and that all the increase is in a lineal fashion. The regression lines of the relative values, (i. e., taking each control value as 1) of all the values obtained, and the regression lines of cell volume, protein and NP-SH are identical, whereas those of NP-SS and P-SH appear to be widely seperated. However, the difference of those two lines (NP-SS & P-SH) were found to be not significant statistically (p>0.05). Therefore, it can be concluded from the above results that all the values examined increase in a lineal fashion with no statistically significant difference among them. Also, with the radiation dose of 1,200 r, the ELD cell becomes enlarged and swollen progressively up to 60 hours post-irradiation and it becomes more than two times of the original normal size at 60 hours after the irradiation, and up to this stage, it seems apparent that the cell division has been slow due to the X-irradiation applied in this experiment. It is well understandable that the contents of NP-SH, NP-SS, P-SH and protein of the ELD cells increase in parallel with the increase of the cell volume by the X-ray does used, but it also seems interesting to note that all the cellular substances tested show no appreciable difference in the pattern of increase.

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Effect of Brown Algae (Undaria pinnatifida)-Noodle on Lipid Metabolism in Serum of SD-Rats (미역 (Undaria pinnatifida) 국수가 SD계 흰쥐의 혈청 지질대사에 미치는 영향)

  • CHOI Jin-Ho;KIM Dong-Woo;KIM Jung-Hwa;KIM Dae-Ik;KIM Chang-Mok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.1
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    • pp.42-45
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    • 1999
  • Our previous studies have demonstrated the biological effects of alginic acid as a brown algae (Undaria pinnatifida) component on inhibitory action of obesity using animal model. Sprague-Dawely (SD) male rats were fed experimental diets ($10\%,\;20\%$ and $40\%$ brown algae noodle: BA-noodles) for 4 weeks. Effects of BA-noodles on triglyceride (TG), total cholesterol. LDL and HDL-cholesterol, and atherogenic ($10\%\~15\%$ and $15\%\~18%$, respectively) by administration of $10\%,\;20\%$and $40\%$ BA-noodles compared with control group. HDL-cholesterol contents in serum of SD rats for 4 weeks significantly increased in ranges of 7 to $16\%$ by administration of $10\%,\;20\%$ and $40\%$ BA-noodles compared with control group. Atherogenic index (AI) in serum of SD rats as a initial attack markers of chronic degenerative disease for 4 weeks remarkably decreased in ranges of 14 to $28\%$ by the adminstration of $10\%,\;20\%$ and $40\%$ BA-noodles compared with control group. These results suggest that administration of BA-noodle can not only effectively inhibit chronic degenerative disease, but also may be intervent the aging process.

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Study on the Fire Risk Prediction Assessment due to Deterioration contact of combustible cables in Underground Common Utility Tunnels (지하공동구내 가연성케이블의 열화접촉으로 인한 화재위험성 예측평가)

  • Ko, Jaesun
    • Journal of the Society of Disaster Information
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    • v.11 no.1
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    • pp.135-147
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    • 2015
  • Recent underground common utility tunnels are underground facilities for jointly accommodating more than 2 kinds of air-conditioning and heating facilities, vacuum dust collector, information processing cables as well as electricity, telecommunications, waterworks, city gas, sewerage system required when citizens live their daily lives and facilities responsible for the central function of the country but it is difficult to cope with fire accidents quickly and hard to enter into common utility tunnels to extinguish a fire due to toxic gases and smoke generated when various cables are burnt. Thus, in the event of a fire, not only the nerve center of the country is paralyzed such as significant property damage and loss of communication etc. but citizen inconveniences are caused. Therefore, noticing that most fires break out by a short circuit due to electrical works and degradation contact due to combustible cables as the main causes of fires in domestic and foreign common utility tunnels fire cases that have occurred so far, the purpose of this paper is to scientifically analyze the behavior of a fire by producing the model of actual common utility tunnels and reproducing the fire. A fire experiment was conducted in a state that line type fixed temperature detector, fire door, connection deluge set and ventilation equipment are installed in underground common utility tunnels and transmission power distribution cables are coated with fire proof paints in a certain section and heating pipes are fire proof covered. As a result, in the case of Type II, the maximum temperature was measured as $932^{\circ}C$ and line type fixed temperature detector displayed the fire location exactly in the receiver at a constant temperature. And transmission power distribution cables painted with fire proof paints in a certain section, the case of Type III, were found not to be fire resistant and fire proof covered heating pipes to be fire resistant for about 30 minutes. Also, fire simulation was carried out by entering fire load during a real fire test and as a result, the maximum temperature is $943^{\circ}C$, almost identical with $932^{\circ}C$ during a real fire test. Therefore, it is considered that fire behaviour can be predicted by conducting fire simulation only with common utility tunnels fire load and result values of heat release rate, height of the smoke layer, concentration of O2, CO, CO2 etc. obtained by simulation are determined to be applied as the values during a real fire experiment. In the future, it is expected that more reliable information on domestic underground common utility tunnels fire accidents can be provided and it will contribute to construction and maintenance repair effectively and systematically by analyzing and accumulating experimental data on domestic underground common utility tunnels fire accidents built in this study and fire cases continuously every year and complementing laws and regulations and administration manuals etc.

Performance effectiveness of pediatric index of mortality 2 (PIM2) and pediatricrisk of mortality III (PRISM III) in pediatric patients with intensive care in single institution: Retrospective study (단일 병원에서 소아 중환자의 예후인자 예측을 위한 PIM2 (pediatric index of mortality 2)와 PRIMS III (pediatric risk of mortality)의 유효성 평가 - 후향적 조사 -)

  • Hwang, Hui Seung;Lee, Na Young;Han, Seung Beom;Kwak, Ga Young;Lee, Soo Young;Chung, Seung Yun;Kang, Jin Han;Jeong, Dae Chul
    • Clinical and Experimental Pediatrics
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    • v.51 no.11
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    • pp.1158-1164
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    • 2008
  • Purpose : To investigate the discriminative ability of pediatric index of mortality 2 (PIM2) and pediatric risk of mortality III (PRISM III) in predicting mortality in children admitted into the intensive care unit (ICU). Methods : We retrospectively analyzed variables of PIM2 and PRISM III based on medical records with children cared for in a single hospital ICU from January 2003 to December 2007. Exclusions were children who died within 2 h of admission into ICU or hopeless discharge. We used Students t test and ANOVA for general characteristics and for correlation between survivors and non-survivors for variables of PIM2 and PRISM III. In addition, we performed multiple logistic regression analysis for Hosmer-Lemeshow goodness-of-fit, receiver operating characteristic curve (ROC) for discrimination, and calculated standardized mortality ratio (SMR) for estimation of prediction. Results : We collected 193 medical records but analyzed 190 events because three children died within 2 h of ICU admission. The variables of PIM2 correlated with survival, except for the presence of post-procedure and low risk. In PRISM III, there was a significant correlation for cardiovascular/neurologic signs, arterial blood gas analysis but not for biochemical and hematologic data. Discriminatory performance by ROC showed an area under the curve 0.858 (95% confidence interval; 0.779-0.938) for PIM2, 0.798 (95% CI; 0.686-0.891) for PRISM III, respectively. Further, SMR was calculated approximately as 1 for the 2 systems, and multiple logistic regression analysis showed ${\chi}^2(13)=14.986$, P=0.308 for PIM2, ${\chi}^2(13)=12.899$, P=0.456 for PRISM III in Hosmer-Lemeshow goodness-of-fit. However, PIM2 was significant for PRISM III in the likelihood ratio test (${\chi}^2(4)=55.3$, P<0.01). Conclusion : We identified two acceptable scoring systems (PRISM III, PIM2) for the prediction of mortality in children admitted into the ICU. PIM2 was more accurate and had a better fit than PRISM III on the model tested.

Development of Wholistic Hospice Nursing Intervention Program for In-patient of Hospice Palliative Care Unit (병동형 호스피스 대상자를 위한 전인적 호스피스 간호중재 프로그램의 개발)

  • Kang, Eun-Sil;Choi, Sung-Eun;Kang, Sung-Nyun
    • Korean Journal of Hospice Care
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    • v.7 no.1
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    • pp.29-45
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    • 2007
  • People in the end of life and their families suffer in their physical disease and other aspects as a whole person. They need hospice care to palliate their total suffering in physical, emotional, social and also spiritual aspect through professional hospice team. To care their whole personal needs, hospice team must be a multi-discipline team which consists of medical doctors, nurses, social workers, pastors and volunteers. Recently those who die in hospice palliative care unit have trend to increase more than in home year by year. So it is necessary to develop the nursing intervention program to be performed by multi-discipline team approach for in-patient of hospice palliative care unit. The purposes of this study were to develop of wholistic hospice nursing intervention program for inpatient of hospice palliative care unit. The subjects of study were collected from 30 patients those who were over 18 years old and admitted in hospice palliative care unit of S hospital in P city with agreement in hospice palliative care in their terminal disease. The period of data collection was from December 15, 2003 to March 15, 2004. The result were as follows : 1. The result of Wholistic Hospice Nursing Program's development was as follow : A Wholistic Hospice Nursing Program was developed by me in this study is one of the service program for hospice palliative care unit. It was named as ‘Rainbow Program’ to be approached easily by hospice patients. The purposes of it are to improve the quality of life of the terminal patients with their dignity, to help them live in abundant and meaningful in their lives, to care them in peaceful in dying process with understanding them in whole personal, and also to palliate the grief and suffering of the bereaved. It was provided by hospice professionals(nurses, medical doctors, social worker, pastors, art therapists) and volunteers those who were educated in hospice for multi-diciplinary team approach to collaborate with each role play I 20-30 minuters of each through visiting their rooms individually and a place of hospice palliative care unit of S hospital in P city. The subjects of it were the terminal patients those who admitted hospice palliative care unit and their familes. with agreement in hospice palliative care in their terminal disease. The characteristics of it were multi-disciplinary team approach, whole personal care, individual care and total care according to their needs in their condition. The contents of it were pain control, symptom control, counseling patient, counseling family, hair cutting, hair shampooing, bed bath, recreation, taking a walk, event of culture(screen, recital, festival of praises, exhibition and so on), pastoral counseling, ritual service in bed, praying, service in bed, sing a worship praise, listening to the music, sharing remembrance of life, individual visiting music service(sing and praying), meditation Bible, art therapies(dance and drawing), social worker's counselling, confessing and sharing love and thanksgiving. The experimental group subjects participated in Wholistic Hospice Nursing Program which takes 120 minutes per session, total 10 sessions(total 1,200 minutes) altogether. In conclusion, this Wholistic Hospice Nursing Intervention can be used actively for whole personal well-being of the patients in hospice palliative in hospice palliative care unit and also applied in hospice practice as an useful model of multi-disciplinary team approach by hospice professionals.

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