• Title/Summary/Keyword: age reduction

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Nutritional and Tissue Specificity of IGF-I and IGFBP-2 Gene Expression in Growing Chickens - A Review -

  • Kita, K.;Nagao, K.;Okumura, J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.5
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    • pp.747-754
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    • 2005
  • Nutritional regulation of gene expression associated with growth and feeding behavior in avian species can become an important technique to improve poultry production according to the supply of nutrients in the diet. Insulin-like growth factor-I (IGF-I) found in chickens has been characterized to be a 70 amino acid polypeptide and plays an important role in growth and metabolism. Although it is been well known that IGF-I is highly associated with embryonic development and post-hatching growth, changes in the distribution of IGF-I gene expression throughout early- to late-embryogenesis have not been studied so far. We revealed that the developmental pattern of IGF-I gene expression during embryogenesis differed among various tissues. No bands of IGF-I mRNA were detected in embryonic liver at 7 days of incubation, and thereafter the amount of hepatic IGF-I mRNA was increased from 14 to 20 days of incubation. In eyes, a peak in IGF-I mRNA levels occurred at mid-embryogenesis, but by contrast, IGF-I mRNA was barely detectable in the heart throughout all incubation periods. In the muscle, no significant difference in IGF-I gene expression was observed during different stages of embryogenesis. After hatching, hepatic IGF-I gene expression as well as plasma IGF-I concentration increases rapidly with age, reaches a peak before sexual maturity, and then declines. The IGF-I gene expression is very sensitive to changes in nutritional conditions. Food-restriction and fasting decreased hepatic IGF-I gene expression and refeeding restored IGF-I gene expression to the level of fed chickens. Dietary protein is also a very strong factor in changing hepatic IGF-I gene expression. Refeeding with dietary protein alone successfully restored hepatic IGF-I gene expression of fasted chickens to the level of fed controls. In most circumstances, IGF-I makes a complex with specific high-affinity IGF-binding proteins (IGFBPs). So far, four different IGFBPs have been identified in avian species and the major IGFBP in chicken plasma has been reported to be IGFBP-2. We studied the relationship between nutritional status and IGFBP-2 gene expression in various tissues of young chickens. In the liver of fed chickens, almost no IGFBP-2 mRNA was detected. However, fasting markedly increased hepatic IGFBP-2 gene expression, and the level was reduced after refeeding. In the gizzard of well-fed young chickens, IGFBP-2 gene expression was detected and fasting significantly elevated gizzard IGFBP-2 mRNA levels to about double that of fed controls. After refeeding, gizzard IGFBP-2 gene expression decreased similar to hepatic IGFBP-2 gene expression. In the brain, IGFBP-2 mRNA was observed in fed chickens and had significantly decreased by fasting. In the kidney, IGFBP-2 gene expression was observed but not influenced by fasting and refeeding. Recently, we have demonstrated in vivo that gizzard and hepatic IGFBP-2 gene expression in fasted chickens was rapidly reduced by intravenous administration of insulin, as indicated that in young chickens the reduction in gizzard and hepatic IGFBP-2 gene expression in vivo stimulated by malnutrition may be, in part, regulated by means of the increase in plasma insulin concentration via an insulin-response element. The influence of dietary protein source (isolated soybean protein vs. casein) and the supplementation of essential amino acids on gizzard IGFBP-2 gene expression was examined. In both soybean protein and casein diet groups, the deficiency of essential amino acids stimulated chickens to increase gizzard IGFBP-2 gene expression. Although amino acid supplementation of a soybean protein diet significantly decreased gizzard IGFBP-2 mRNA levels, a similar reduction was not observed in chickens fed a casein diet supplemented with amino acids. This overview of nutritional regulation of IGF-I and IGFBP-2 gene expression in young chickens would serve for the establishment of the supply of nutrients to diets to improve poultry production.

Effects of clomiphene citrate on ovarian function and embryo developmental capacity in the rat (랫드에 있어서 클로미펜 시트레이트가 난소기능 및 수정란 발육성에 미치는 영향)

  • Yun, Young-won;Kwun, Jong-kuk
    • Korean Journal of Veterinary Research
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    • v.32 no.1
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    • pp.15-24
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    • 1992
  • The effects of CC the ovulatory response, oocyte normality, ovarian steroidogenesis and subsequent embryo developmental potential were examined in PMSG-treated rats. On Days of 25~27 of age, immature female Sprague Dawley rats were treated with three different doses(0.05, 0.1 or 1.0mg /day) of clomiphene citrate or vehicle. The females subsequently received 4IU PMSG on Day 28 and/or 10IU hCG on Day 30, and were killed on Day 31. Some females given 0.1mg CC or vehicle with 4IU PMSG were then mated and killed on Days 2, 3, 4 and 5 of pregnancy. Compared to vehicle(control) group, by increasing the doses of CC, there were a significant decrease in the ovulatory response as judged by both the proportion of rats ovulating and the mean number of oocytes per rat and a marked reduction of ovarian weight. The increasing doses of CC substantially promoted the degeneration(%) of oocytes ovulating in a dose-dependent manner. The CC-mediated inhibitions of the ovulatory response and ovarian weight were oompletely overcome by a subsequent treatment of hCG. Increasing doses of CC resulted in a siginificant elevation of serum estradiol with the decreased levels of progesterone and androgens. The additive treatment with hCG was effective to reduce the elevation of estradiol and to increase the reduction of progesterone produced by high dose(1.0mg) of CC. The preimplantation embryos recovered from 0.1mg CC-treated pregnant rats demonstrated a progressive early loss from Day 3 of pregnancy with a significant increase in the percentage of degeneration during all periods examined, compared to controls. The rate of progressive embryo cleavage in the CC-treated rats were slower than that in controls from Day 3 of pregnancy. Additionally, the percentage of the cleaved embryos recovered from the CC-treated rats remained significantly lower consistently from Day 2 of pregnancy, compared to control regimen. These results demonstrate a possible mechanism of CC-mediated inhibition of ovulatory response in the rats which may include the attenuation or blockade of the endogenous secretion of gonadotropins and also suggest that its detrimental effects observed on oocyte normality and embryonic development may be caused by abnormal follicular steroidogenesis( especially elevated estradiol) preceding fertilization.

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A DOUBLE BLIND CROSS-OVER COMPARISON OF ANTIDEPRESSANT AND ANTIANXIETY EFFECTS OF PAROXETINE AND PLACEBO IN CHILD-ADOLESCENT AND ADULT DEPRESSIVE NEUROSIS (소아 ${\cdot}$ 청소년 및 성인 우울신경증 환자에 대한 Paroxetine의 항우울 및 항불안 효과 검증 : 위약과의 이중맹 교차 비교실험)

  • Kim, S. Peter;Hong, Kyung-Sue
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.5 no.1
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    • pp.83-92
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    • 1994
  • Paroxetine is a potent and selective serotoin re-uptake inhibitor. It is well known as an effective and safe antidepressant and increasingly used for neurotic or non-psychotic depression with anxiety symptoms. The present study assessed antidepressant and antianxiety efficacy and tolerability of paroxetine against placebo in child-adolescent and adult depressive neurosis patients. 232 subjects aged 8-55 years and meeting DSM-III-R criteria for depressive neurosis or dysthymia were divided into 8 subgroups according to their sex and age(8-11 yeard old, 12-17 years old, 18-35 years old and 36-55 years old subgroup in each male and female group). In each subgroup, the randomly assigned half of the patients were treated with paroxetine(10-30mg/day) and the others with placebo for the first 2 weeks in double blind fashion. After 1 week of drug-washout period, paroxetine and placebo groups were crossed over. The depression and anxiety symptoms were assessed with Hamilton Depression Scale(HDS) and Hamilton Anxiety Scale(HAS) at baseline and every 1 week during the trial periods. The levels of reduction in HDS and HAS scores from baseline after 2-week trial were compared between paroxetine- and placebo- treated periods by paired t-test. In all the 8 subgroups, statistically significant differences between paroxetine and placebo were found on the antidepressant efficacy after 2-week treatment. The antidepressant efficacy of paroxetine compared to placebo was most prominent in child and adolescent female groups. On anxiety symptoms, paroxetine was also significantly more effective than placebo. The antianxiety efficacy of paroxetine compared to placebo was most prominent in male and female child groups and young adult female group aged 18-35 years. As for the adverse effects of paroxetine, 3 out of 232 subjects reported mild indigestion and abdominal pain. however, in all the 3 cases, the symptoms improved without reduction of dosage or discontinuation of the drug. In conclusion, paroxetine showed significantly higher antidepressant and antianxiety efficacy compared to placebo in child-adolescent and adult depressive neurosis patients after 2-week treatment. Further trials of paroxetine in depressive neurosis are warranted to elucidate the long-term antidepressant and antianxiety efficacy of paroxetine.

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A Clinical Analysis of Femur Neck Fracture in Elderly Patients (노년층에서 대퇴경부 골절의 치료)

  • Ihin, Joo-Choul;Ahn, Myun-Whan;Seo, Jae-Sung
    • Journal of Yeungnam Medical Science
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    • v.2 no.1
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    • pp.11-22
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    • 1985
  • Femur neck fracture is well known as one of the major death cause after trauma in elderly patients, and unsolved fracture due to its frequent association with complications such as avascular necrosis and nonunion. Through meticulous evaluation of the patient, hip and surgeon's experiences, reduction of mortality and morbidity as well as rapid recovery of the patient to the preinjury social and ambulatory status without local complications and revision after treatment is urgently needed. Many factors about this fracture In itself were noted, but we have analyzed 18 femur neck fractures of the patients older than 50 years preliminarily according to age, fracture pattern, osteoporosis, etiology and method of treatment with its delay in association with major complications especially avascular necrosis and nonunion. The results are as follows; 1. Of these 18 fractures, 11 were in females, 8 were caused by minor trauma such as slip-down accident and 4 were associated with definite osteoporosis according to the Sing's classification. 2. Fracture pattern of these 18 are undisplaced in 4, displaced subcapital in 11, displaced transcervical in 3. 11 fractures in the patients older than 60 year are composed of 3 undisplaced or impacted fractures and 8 displaced subcapital fractures. 3. These 18 fractures were treated by closed reduction and Internal fixation with multiple pins in 13, and hemiarthroplasty in 4, but one was not treated to die after discharge from hospital. 4. 4 undisplaced or impacted fractures and 3 displaced transcervical fractures were not associated with any complications such as avascular necrosis or nonunion. But 4 of 6 displaced subcapital fractures were complicated by avascular necrosis, 3 of which were reduced in the varus position within 1 week, and the other was reduced in the good position on 1 week after trauma. There was no complication in 2 displaced subcapital fractures reduced in valgus position within 3 days after trauma. According to the above results, the prognosis of the femur neck fracture is dependent upon the fracture pattern and delay in its treatment. So it is inevitable to reduce the fracture in anatomical or valgus position as early as possible. But the arthroplasty may be needed in displaced subcapital fractures delayed for several days, with its reluction in extreme varus position or impossible and with pre-existing disease in the same hip Joint (total hip replacement).

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Genetic Relationship and Structural Characteristics of the Fe-Ti Ore Body and the Sancheong Anorthosite, Korea (산청 회장암과 철-티탄 광체의 구조적 특징과 발생적 관계)

  • Kang, Ji-Hoon;Lee, Deok-Seon
    • Economic and Environmental Geology
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    • v.47 no.6
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    • pp.571-588
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    • 2014
  • It consists of the Precambrian Jirisan metamorphic complex and Sancheong anorthosite complex and the Mesozoic granitoids which intrude them in the Sancheong area, the Jirisan province of Yeongnam massif, Korea. The study area is located in the western part of the stock-type Sancheong anorthosite complex. We performed a detailed fieldwork on the Sancheong anorthosite (SA) and Fe-Ti ore body (FTO) which constitute the Sancheong anorthosite complex, and reinterpreted the origin of FTO foliation and the genetic relationship between them from the foliations, shear zones, occurrences of the SA and FTO. The new structural characteristics between them are as follows: the multilayer structures of FTO, the derived veins of straight, anastomosing uneven types and block structures related to the size reduction of SA, the gradual or irregular boundaries of SA blocks and FTO showing bulbous lobate margins and comb structures, the FTO foliation and linear arrangements of flow occurrence which is not ductile shear deformation, the discontinuous shear zone of SA, the orientation of FTO foliations parallel to the boundaries of SA blocks, the predominance of FTO foliations toward the boundaries of SA blocks and being proportional to the aspect ratio of plagioclase xenocrysts and SA xenoblocks, and the flow folding structures of FTO foliation. Such field evidences indicate that the SA is not fully congealed when the FTO is melt and the fracturing of partly congealed SA causes the derived veins of FTO and the size reduction of SA. Also the gradual or irregular boundaries of SA blocks and FTO result from the mutual reaction between the not fully congealed SA blocks and the FTO melt, and the FTO foliation is a magmatic foliation which was formed by the interaction between the FTO melt and the partly congealed SA blocks. Therefore, these suggest that the SA and FTO are not formed from the intrusion of different magmas in genesis and age but from a coeval and cogenetic magma through multiple fractionation. We predict that the FTO will show an very irregular occurrence injected along irregular fractures, not the regular occurrence like as the intrusive vein and dike. It can be applied to the designing of Fe-Ti mineral resource exploration in this area.

Recent Early Operative Outcomes of Comprehensive Aortic Root & Valve Reconstruction (CARVAR) Procedure (종합적 대동맥 근부 및 판막 재건술의 최근 초기 수술성적)

  • Lee, Sung-Jun;Shin, Je-Kyoun;Kim, Dong-Chan;Kim, Jin-Sik;Kim, Jun-Seok;Chee, Hyun-Keun;Song, Meong-Gun
    • Journal of Chest Surgery
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    • v.42 no.6
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    • pp.696-703
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    • 2009
  • Background: A Comprehensive Aortic Root and Valve Reconstruction (CARVAR) procedure is comprised of aortic root wall reconstruction and corrections of the leaflets for treating various aortic valve diseases. We evaluated our recent early clinical experience with the CARVAR procedure. Material and Method: From October 2007 to September 2008, 114 cases (66 males) of CARVAR procedures were performed, The mean patient age was 53 years (range: 14~84) The patients were divided into 4 groups: 1) the AAR group: aortic regurgitation with aortic root wall deformity such as annulo-aortic ectasia or ascending aortic aneurysm (n=18), 2) the IAR group: isolated AR with leaflet abnormality (n=42), 3) the IAS group: isolated aortic stenosis (n=51) and 4) the PAVR group: previous aortic valve replacement (n=3). Sinotubular junction (STJ) reduction was done in all the patients, leaflet correction was done in 10 of the AAR group patients and in all the patients of the other groups, annulus reduction was done in 14 of the MR group patients and in 6 of the IAR group patients. Aortic dissection was excluded from this analysis. Result: There was no mortality or follow-up death. The diameter of the aortic sinus decreased from $54.6{\pm}8.4$ mm to $38.3{\pm}3.8$ mm in the AAR group, the mean AR grade decreased from 3.2 to 0.2 in the IAR group, the mean aortic valve pressure gradient decreased from $47.1{\pm}24.4$ mmHg to $15.1{\pm}11.7$ mmHg in the IAS group and the mean AR grade decreased to 0 in the PAVR group. Balloon type coronary perfusion cannula-related coronary ostial stenosis developed in 4 patients and this was treated with OPCAB in three patients and with PTCA in one patient. Two patients developed postoperative infectious endocarditis. All the patients were discharged and followed up in a stable condition. Conclusion: The CARVAR procedure showed excellent short term results, but a good further follow up result is required to apply this procedure to most kinds of aortic valve diseases.

A Study of the Effect of Structured Rehabilitation Education on the Stress of the Family with Stroke Patients (구조화된 재활교육이 뇌졸중환자 가족의 스트레스에 미치는 영향)

  • Kim, Byung-Eun;Lee, Jung-Min;Lee, Hyang-Yeon
    • Journal of East-West Nursing Research
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    • v.1 no.1
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    • pp.22-39
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    • 1997
  • Purpose: The purpose of this study is to evaluate the effect of rehabilitation education on the reduction of the stress of family members who have patients suffering from stroke and to find a new way to nurse the patients and their family. Subjects & Methods: The subjects were sixty-one family members with the patients who had been hospotalized in K hospital of oriental medicine from september the 9th, 1996 to september the fourteen, 1996. This study was performed by simulated control group pretest-posttest design; pretest was done on the control group through a questionnaire, counselling and observation while posttest was done on the experimental group 1-2 days after systemic rehabilitation education. To teach the patients and their family, the amended version of a book written by Lee Hae-jin was used as a tool for systemic rehabilitation education. As a method to estimate ADL score, modified Kang's method was applied and ADL score was measured by well-trained technician. As for the tool to estimate the degree of family stress, Choi's method adjusted to this study was applied. In the analysis of the data, social property of the patient and the characteristic of the disease were surveyed in $X^2$ examination to confirm the consistency between the experimental group and the control group. The diffrence in the degree of the stress, which is a dependent factor, was examined by t-test. The difference in ADL score between the experimental group and the control group was examined by t-test. The difference in the degree of the stress according to the general feature of the family with stroke patient, social property of the patients and the characteristic of the disease were surveyed by F examination. The difference in family stress according to the degree of ADL was surveyed by F examination. RESULTS: 1. After hypothetically-examined systemic rehabilitation education, the total of the score of family stress surveyed in 34 items of three domains was compared between the experimental group and the control group. There was no statistically significant difference between two groups; mean score of experimental group=2.28, that of control group=2.93(t=.17, df=59, p=. 66). 2. In the survey on family stress in 34 items, the items over mean score 3.0 were firstly the anxiety of possible disability and relapse of the disease and secondly to watch the patient's suffering without doing anything in the domain of the change of the disease and the difficulty in caring. And the items of the lowest stress with less than mean 2.0 score were little chance to meet the relative and friends, inconsistent treatment and attitude of the medical workers and the change of the attitude of the relative due to the patient orderly in the domain of social and personal relation and the responsibility as the family. The items which showed the difference between two groups were aggravation of neighboring patient(t=3.36, df= 59, p=.001) and the possibility of patient's death(t=2.19, df=58.38, p=.033) in the domain of the change of the disease and the difficulty in caring. 3. In the study on the stress difference according to general features of the family with the stroke patient, the score of family stress with the occupation was higher with mean 2.49 than that of the family stress without occupation with mean 2.16, but there was no significant difference. (F=5.21, df=1/59, p=.026). 4. In the study on the stress difference according to social property of the patient and the characteristic of the disease, there was significant difference in the age of the patients (F=2.98, df=3/57, p=.039). These results show that even if there is no statistically significant difference between two groups, sixteen of the experimental group are less than 3.0 in ADL score(standard 6 score)while eight of the control group are less than 3.0 and that ten of the experimental group are in the year range of 39-49 while four of the control group are in the year range of 39-49 which showed significant difference in family stress. These imply that there is a possibility that the experimental group have serious and fundamental stress resulting in high pretest stress compared with the control group. It might be due to the characteristic of simulated control group pretest-posttest design that the psychologic-supportive effect by the education was not observed. On the basis of these results, the followings are suggested. 1) A study on the nursing-mediated method to reduce the stress in the items which are not resolved by rehabilitation education, a study on nursing according to the patient's age and a study on the supportive nursing toward the family with occupation are required. 2) More than two times consecutive nursing-mediated rehabilitation education to measure the family stress is required. 3) Comprehensive and multilateral systemic education program including the instruction on western-eastern medicine, physical therapy, exercise and diet through collaboration of the experts in each field is required. 4) Family stress at home as well as in the hospital needs to be estimated and home rehabilitation and home-nursing needs to be continued.

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Hematologic Changes and Factors Related to Postoperative Hemorrhage Following Cardiopulmonary Bypass (체외순환에 따른 혈액학적 변화와 술후 출혈에 관계하는 인자에 관한 연구)

  • 김하늘루;황윤호;최석철;최국렬;김승우;조광현
    • Journal of Chest Surgery
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    • v.31 no.10
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    • pp.952-963
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    • 1998
  • Background: Cardiopulmonary bypass(CPB)-induced hemostatic defects may result increased possibility of excessive hemorrhage and additional multiple transfusion reactions or reoperation. Particularly, fibrinolytic activation and decreased platelet count and function by CPB were proposed as a predictor of hemorrhage during postoperative periods in several reports. Materials and methods: Present study, which was conducted in 20 adult patients undergoing CPB, was prospectively designed to examine the hematologic changes, including fibrinolytic activation during and after CPB and to clarify the relationships between these changes and the magnitude of the postoperative nonsurgical blood loss. The serial blood samples for measurment of hematologic parameters were taken during operation and postoperative periods. Blood loss was respectively counted via thoracic catheter drainage at postoperative 3, 6, 12, 24, 48 hours and total period. Results: The results were obtained as follows:Platelet count rapidly declined following CPB(p<0.01), which its decreasing rate was an inverse proportion to total bypass time(TBT, r=0.55, p=0.01), And platelet count in postoperative 7th day was barely near to its control value. Fibrinogen degradating product(FDP) and D-dimer level significantly increased during CPB(p<0.0001, p<0.0001, respectively), and both of fibrinogen and plasminogen concentration correlatively decreased during CPB(r=0.57, p<0.01), implying activation of fibrinolytic system. Postoperative bleeding time (BT), postoperative activated partial thromboplastin time(aPTT) and postoperative prothrombin time (PT) were significantly prolonged as compare with each control value (p=0.05, p<0.0001, p<0.0001, respectively). Total blood loss was positively correlated with patient's age, aortic clamping time (ACT) and TBT, while there was negative correlation between platelet count and blood loss at pre-CPB, CPB-off and the 1st postoperative day, and in some periods. Postoperative aPTT and postoperative PTwere positively related to postoperative 6 hr and 48 hr blood loss(r=0.53, p=0.02; r=0.43, p=0.05) but not to total blood loss, whereas there was no relationship between postoperative BT and blood loss at any period. Conclusions: These observations suggest that CPB results various hematologic changes, including fibrinolytic activation and severe reduction in platelet count. Diverse factors such as age, platelet count, ACT, TBT and postoperative aPTT and PT may magnify the postoperative bleeding. This study will be a basic reference in understanding CPB-induced hemostatic injuries and in decreasing the postoperative hemorrhage

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Small Bowel Intussusception in Children: Spontaneous Resolution vs. Surgical Intervention (소아에서 소장형 장중첩증; 자연 정복과 수술적 치료의 비교)

  • Park, Mi-Ran;Lim, Mi-Sun;Seo, Jeong-Kee;Ko, Jae-Sung;Chang, Ju-Young;Yang, Hye-Ran;Lim, Yoon-Joung;Kim, Woo-Sun
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.13 no.2
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    • pp.128-133
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    • 2010
  • Purpose: Intussusception is one of the most common causes of an acute abdomen in infancy. The majority of pediatric cases of intussusception are of the ileocolic type and usually idiopathic. Small bowel intussusception is rarely diagnosed in children, and few cases have been reported. The purpose of this study was to determine the clinical features and causes of small bowel intussusception in children. Methods: We retrospectively reviewed the clinical and radiologic findings of 21 children with small bowel intussusception who were admitted to Seoul National University Children's Hospital between March 2005 and January 2010. Results: The clinical presentation of small bowel intussusception included abdominal pain or irritability (85%), vomiting (23%), fever (14%), bloody stools (14%), and abdominal masses (4%). Six patients required surgical management. Ultrasonography showed that the mean diameter of the lesions and mean thickness of the outer rims were 1.6${\pm}$0.7 and 1.7${\pm}$1.8 mm, respectively. Eleven lesions were located in the left abdominal or paraumbilical regions. Children who underwent surgical management were older than children with transient small bowel intussusception (mean age, 51 vs. 109 months). The mean diameter of the lesions and mean thickness of the outer rims were greater in the surgically-managed group. The location of intussusception was not significantly different between the two groups. Conclusion: Small bowel intussusception was spontaneously reduced in a large number of pediatric patients. However, sonographic demonstration of larger size, older age, and pathologic lead point warrant surgical intervention.

Skarn Formation in Metamorphic Rocks of the Chungju Mine Area (충주광산 지역 계명산층의 텅스텐 스카른화작용)

  • Kim, Gun-Soo;Park, Maeng-Eon
    • Economic and Environmental Geology
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    • v.28 no.3
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    • pp.185-197
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    • 1995
  • Tungsten skarns in the Chungju mine which consists mainly of strata-bound type iron ore deposits are found in the vicinity of the contact between the age-unknown Kyemeongsan Formation and granitic rock intrusions of Mesozoic age($134{\pm}2Ma$). Tungsten skarns were formed extensively from alumina and silica-rich schistose rocks by the introduction of calcium and iron from hydrothermal solution. The skarns comprise a metasomatic column and are subdivided into four facies; garnet facies, wollastonite facies, epidote facies and chlorite facies. The skarn process in time-evolutional trend can be divided broadly into the four facies in terms of the paragenetic sequence of calc-silicates and their chemical composition. Skarn and ore minerals were formed in the following sequence; (1) garnet facies, adjacent to biotite granite, containing mainly garnet(>Ad96) and magnetite, (2) wollastonite facies containing mainly wollastonite and garnet(Ad95~60), (3) epidote facies, containing mainly epidote(Ps35~31), quartz, andradite-grossular(Ad63~50), and scheelite, (4) chlorite facies, adjacent to and replacing schist, containing mainly chrolite, muscovite, quartz, calcite, epidote(Ps31~25), hematite and sulfides. The mineral assemblage and mineral compositions. suggest that the chemical potentials of Ca and Fe increased toward the granitic rock, and the component Al, Mg, K, and Si decreased from the host rock to granitic rock. The homogenization temperature and salinity of fluid inclusion in scheelite, quartz and epidote of epidote facies skarn is $300-400^{\circ}C$ and 3-8wt.% eqiv. NaCl, respectively. ${\delta}^{34}S$ values of pyrite and galena associated with chlorite facies skarn is $9.13{\sim}9.51%_{\circ}$ and $5.85{\sim}5.96%_{\circ}$, respectively. The temperature obtained from isotopic com· position of coexisting pyrite-galena is $283{\pm}20^{\circ}C$. Mineral assemblages and fluid inclusion data indicate that skarn formed at low $X_{CO_2}$, approximately 0.01. Temperature of the skarn mineralization are estimated to be in the range of $400^{\circ}C$ to $260^{\circ}C$ and pressure to be 0.5 kbar. The oxygen fugacity($fo_2$) of the skarn mineralization decreased with time. The early skarn facies would have formed at log $fo_2$ values of about -25 to -27, and late skarn facies would have formed at log $fo_2$ values of -28 to -30. The estimated physicochemical condition during skarn formation suggests that the principal causes of scheelite mineralization are reduction of the ore·forming fluid and a decrease in temperature.

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