• 제목/요약/키워드: Precipitating factors

검색결과 68건 처리시간 0.027초

THE COLOR STABILITY OF AESTHETIC RESTORATIVE MATERIALS RESULTING FROM ACCELERATED AGING

  • Lee, Jeong-Seon;Suh, Kyu-Won;Ryu, Jae-Jun
    • 대한치과보철학회지
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    • 제46권6호
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    • pp.577-585
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    • 2008
  • STATEMENT OF PROBLEM: The discoloration of anterior teeth restoration is one of the material problems demanding retreatment. OBJECTIVES: To evaluate the color stability and affecting factors on esthetic restorative materials when subjected to accelerated aging. MATERIAL AND METHODS: This study was conducted using porcelain disks (IPS Empress 2-glazed, IPS Empress 2-polished), direct restorative resin disks (SYNERGY Duo) and indirect restorative resin disks (Sinfony, TESCERA ATL). Accelerated aging was done by precipitating the specimens in 38.C distilled water and irradiating with xenon light, and the total irradiation was 397.98 KJ/mm. Color and microhardness change of the specimens were measured before accelerated aging and after 100 hours, 200 hours and 300 hours of accelerated aging, and Surface of the specimens were examined with SEM before and after 300 hours of accelerated aging. RESULTS: 1. After 300 hours' accelerated aging, a ${\Delta}E$ value was 3.3 or lower in IPS Empress 2-glazed, IPS Empress 2-polished and Sinfony. 2. After 300 hours' accelerated aging, gloss was lost and surface changes including microcracks were observed in TESCERA ATL and SYNERGY Duo, and color changes of them ranged between 3.58 and 6.40 ${\Delta}E$ units. 3. During 300 hours' accelerated aging, the microhardness of surface was increased by 3.21 - 19.64% in all kinds of composites resin. CONCLUSION: After 300 hours' accelerated aging, SEM images IPS Empress 2-glazed, IPS Empress 2-polished and Sinfony showed little morphological change and their color changes were considered to be clinically acceptable. And there was significant correlation between microhardness changes and color changes of composites (P < .05).

협심증이 의심되어 운동부하검사를 받은 여성들의 흉통에 관한 내용분석 (Content Analysis of Experiences of Chest Pain in Women Who Underwent the Treadmill Test with an Impression of Angina Pectoris)

  • 최명애;이명선;안경애;임은옥
    • 성인간호학회지
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    • 제14권3호
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    • pp.459-469
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    • 2002
  • Purpose: Experience of chest pain may be different in women from that of men and this discrepancy may cause misdiagnosis of angina contribute to mortality by this disease in women. The purpose of this study was to analyze the characteristics of chest pain and responses to the symptoms in women. Method: A content analysis was conducted with interviewed data obtained from women who underwent the treadmill test Result: Seven major categories were identified from this content analysis: attributes of chest pain; accompanied symptoms; precipitating factors; relief strategies; family support; communication with physicians; and effects of chest pain on their lives. Characteristics of pain were described as heaviness, tightness, heating sensation, tearing, and others. Duration and intensity of pain varied in a wide range. Radiating pain presented in 9 patients, and the locations of radiation were throat, neck, shoulder arm and fingers. Women tended not to respond actively to their chest pain, and didn't get appropriate support either from their family or from their physicians when they reported chest pain. Conclusion: Women express non-typical as well as typical patterns of pain when they experience chest pain. Clinicians have to consider the variability of symptoms when they assess women with suspicions of angina.

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외상성 뇌손상 후의 불안장애 (Anxiety Disorders after Traumatic Brain Injury)

  • 김영철
    • 생물정신의학
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    • 제7권1호
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    • pp.46-54
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    • 2000
  • 외상성 뇌손상으로 외상 후 스트레스 장애, 범불안장애, 공황장애, 강박장애, 공포장애 등의 불안장애가 비교적 흔히 발생할 수 있다. 그러나 빈발하는 불안장애인데 비해 의사들로부터 적절하게 관심을 받지도 못했으며 치료받지도 못하였다. 외상성 뇌손상 후 불안장애는 뇌손상 자체에 의해, 뇌손상과 기능상실에 대한 환자 또는 간호인의 반응에 의해 증상이 발생하기도 하고 지속되기도 한다. 의사는 이들 환자들을 진단하고 치료하기 위해서는 우선 뇌손상의 기전과 양상에 대해 지식이 있어야 하며, 불안증상을 호소하는 외상성 뇌손상 환자를 이해하고 수용하고 지지해주는 태도를 취해야 하며, 불안증상이 뇌손상에 의한 것인지 통상적인 불안 증상인지 확인해야 한다. 이들 뇌손상 환자들은 약물의 부작용에 아주 취약하기 때문에 약물치료시에는 약물의 작용기전은 말할 것도 없고 부작용에 대해 잘 알고 있어야 한다.

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Production of a Recombinant Laccase from Pichia pastoris and Biodegradation of Chlorpyrifos in a Laccase/Vanillin System

  • Xie, Huifang;Li, Qi;Wang, Minmin;Zhao, Linguo
    • Journal of Microbiology and Biotechnology
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    • 제23권6호
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    • pp.864-871
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    • 2013
  • The recombinant strain P. pastoris GS115-lccC was used to produce laccase with high activity. Factors influencing laccase expression, such as pH, methanol concentration, copper concentration, peptone concentration, shaker rotate speed, and medium volume were investigated. Under the optimal conditions, laccase activity reached 12,344 U/L on day 15. The recombinant enzyme was purified by precipitating and dialyzing to electrophoretic homogeneity, and was estimated to have a molecular mass of about 58 kDa. When guaiacol was the substrate, the laccase showed the highest activity at pH 5.0 and was stable when the pH was 4.5~6.0. The optimal temperature for the laccase to oxidize guaiacol was $60^{\circ}C$, but it was not stable at high temperature. The enzyme could remain stable at $30^{\circ}C$ for 5 days. The recombinant laccase was used to degrade chlorpyrifos in several laccase/mediator systems. Among three synthetic mediators (ABTS, HBT, VA) and three natural mediators (vanillin, 2,6-DMP, and guaiacol), vanillin showed the most enhancement on degradation of chlorpyrifos. Both laccase and vanillin were responsible for the degradation of chlorpyrifos. A higher dosage of vanillin may promote a higher level of degradation of chlorpyrifos, and the 2-step addition of vanillin led to 98% chlorpyrifos degradation. The degradation of chlorpyrifos was faster in the L/V system ($k_{obs}$ = 0.151) than that in the buffer solution ($k_{obs}$ = 0.028).

노인의 신체질환과 자살사고 간의 연관성 (Associations between Physical Disorders and Suicidal Ideation in Elders)

  • 박철;강희주;이주연;김선영;배경열;김성완;김재민;신일선;윤진상
    • 대한불안의학회지
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    • 제10권1호
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    • pp.24-29
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    • 2014
  • Objectives : This study aimed to investigate the associations between physical disorders and prevalent/incident suicidal ideation in a community dwelling older population aged 65 years or over. Methods : 1204 people aged 65 years or over evaluated at baseline. Suicidal ideation was identified using the questions from the community version of the Geriatric Mental State Schedule ("GMS B3"). Reported physical disorders covering 11 common and generally chronic health problems were ascertained. Covariates included were depression, age, gender, years of education, accommodation status, past occupation, and current occupation. Of 1066 without suicidal ideation at baseline, 805 (76%) were followed 2 years later, and incident suicidal ideation was evaluated. Results : Prevalent suicidal ideation was significantly associated with 4 of 11 physical disorders: eyesight problems, persistent cough, heart disease and paralysis or weakness in one leg or arm. Incident suicidal ideation was associated with 3 physical disorders: asthma, high blood pressure and paralysis or weakness in one leg or arm. Both prevalent and incident suicidal ideation were significantly associated with increased number of physical disorders. Conclusions : Certain physical disorders were comorbid and precipitating factors of suicidal ideation in elders. And appropriate intervention and treatment of physical disorders might prevent suicidal ideation in elderly.

단주동맹 참여자의 특성 (The Characteristics of the Participants of Alcoholics Anonymous)

  • 홍성진;이상연;백주희
    • 정신신체의학
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    • 제5권1호
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    • pp.108-117
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    • 1997
  • The purpose of this study is to evaluate the demographic characteristics, alcohol-related characteristics and personality trends in the participants of Alcoholics Anonymous. We compared the 33 participants of Alcoholics Anonymous maintaining abstinence at least over 6 months with 35 hospitalized alcoholic patients who have never attended Alcoholics Anonymous and 32 normal controls. The personality trend was measured by Catell's 16 Personality Factors Questionnaire. -Korean Version. The results were as follows: 1) In the demographic data, the participants of Alcoholics Anonymous were mainly 40's, graduated from high school, married, unemployed, middle class in economic state, first or second sons. 2) In alcohol related characteristics, age of first drinking was mainly distributed from 15 to 19 years-old. The most common psychosocial and environmental problem as precipitating factor of alcohol consumption was the problem with primary supper group and the second one was occupational. Most of them drank everyday, and admitted one time. 3) In the first stratum sources traits, the participants of Alcoholics Anonymous demonstrated significantly higher score than hospitalized alcoholic Patients, but lower than normal control in C-factor(stableness). They demonstrated significantly higher score than hospitalized alcoholic patients and normal controls in O-factor(Guilt-proness) and demonstrated significantly higher score than hospitalized alcoholic patients in Q3-factor(self-control). 4) In the second stratum sources traits, they demonstrated significantly higher score than hospitalized alcoholic patients in EXT-factor(extroversions), and lower score than hospitalized alcoholic patients and normal controls in IND-factor(independence).

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유기산 완충용액의 포화도가 법랑질 및 상아질의 재광화에 미치는 영향과 수산화인회석의 AFM 관찰 (THE EFFECTS OF THE DEGREE OF SATURATION OF ACIDULATED BUFFER SOLUTIONS IN ENAMEL AND DENTIN REMINERALIZATION AND AFM OBSERVATION OF HYDROXYAPATITE CRYSTALS)

  • 박정원;허복;이찬영
    • Restorative Dentistry and Endodontics
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    • 제25권3호
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    • pp.459-473
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    • 2000
  • Dental caries is the most common disease in the maxillofacial area. There are many factors contributing to its development, but complete understanding and prevention is not fully known. Since the structure of the coronal and root portion of the tooth is different, the remineralization and demineralization process is also known to be different. In this study, by using a partially saturated buffer solution, we created artificial enamel and dentin caries and evaluated mineral loss. A remineralization solution with four different degrees of saturation (degree of saturation ; group 1, 0.268, group 2, 0.309, group 3, 0.339, group 4, 0.390, PH 4.3, F-2ppm) was used on a demineralized specimen. The mineral precipitating quantity and depth was evaluated by using microradiography. Using an atomic force microscope (AFM), hydroxyapatite crystals of normal, demineralized, and remineralized enamel and dentin were evaluated. The results were as follows: 1. As the degree of saturation of the remineralizing solution increased, the mineral precipitation in the enamel was increased. In group 4, mineral precipitation was limited near the surface. 2. As the degree of saturation of the remineralizing solution increased, the mineral precipitation in the dentin was decreased and it occurred in a deeper portion. In group 4, however, mineral precipitation occurred on the surface and its quantity increased. 3. There was a statistically significant interaction between enamel and dentin mineral content changes on specimens treated with remineralization and demineralization solution (demineralization r=0.44, remineralization r=0.44, p<0.05). 4. Demineralized hydroxyapatite crystals showed central and peripheral dissolving and widening of intercrystal spaces under the AFM. 5. In dentin remineralization small crystal precipitation occurred between the large crystals. We conclude that by adjusting acidulated buffer solution's degree of saturation, we can control enamel and dentin remineralization. In addition, the AFM is highly useful in evaluating changes in remineralized and demineralized hydroxyapatite crystals.

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유기인계 및 카바메이트계 중독 환자의 심혈관계 양상 (Cardiovascular Manifestations of Acute Organophosphate and Carbamate Poisoning)

  • 이상범;김정호;도병수
    • 대한임상독성학회지
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    • 제2권1호
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    • pp.7-11
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    • 2004
  • Purpose: We would evaluate the cardiovascular manifestations of the patients with acute organophosphate and carbamate poisoning in the emergency department. Methods: This was retrospectively studied with the review of patient's charts, included total 38 patients were admitted during the past two years in the emergency department of Yeungnam university hospital with the diagnosis of organophosphate or carbamate poisoning. Results: Cardiovascular complications were variously developed in many patients. Electrocardiographic findings were as follows; 4 ($10.5\%$) cardiac arrhythmias included 1 cardiac arrest caused by ventricular fibrillation, 14 ($36.8\%$) sinus tachycardias, 3 ($7.9\%$) sinus bradycardias, and 17 ($44.7\%$) normal sinus rhythms. Conduction disturbances were 23 ($60.5\%$) like as prolonged QTc, 4 ($10.5\%$) ST-T changes, 2 (5.3%) first degree AV block, and 3 ($7.9\%$) right bundle branch block were shown. Other cardiovascular complications were 22 ($57.9\%$) hypertensives, 4 ($10.5\%$) hypotensives, 15 ($39.5\%$) tachycardias, 2 ($5.3\%$) bradycardias, 18 ($47.4\%$) hypoxemics, 12 ($31.6\%$) metabolic acidosis, and 9 ($23.7\%$) pulmonary edemas. Sixteen patients ($42.1\%$) needed ventilatory support because of respiratory paralysis. No patients died in hospital and 36 ($94.7\%$) patients were alive-discharged. Conclusion: Cardiovascular complications are variously in patients with acute organophosphate and carbamate poisoning. Especially, some findings included ventricular arrhythmias, QTc prolongation, hypoxemia, acidosis, and blood pressure changes are known as major precipitating factors to increase the mortality. So, intensive support and aggressive treatment are needed in patients shown various cardiovascular manifestations in the emergency department.

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폐니켈-카드뮴 전지 침출액으로부터 아연 분말을 이용한 카드뮴의 치환반응에 대한 연구 (A Study on the Cementation Reaction of Cadmium by Zinc Powders from Leaching Solution of Waste Nickel-Cadmium Batteries)

  • 김민준;박일정;김대원;정항철
    • 자원리싸이클링
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    • 제28권1호
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    • pp.23-31
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    • 2019
  • 폐전자제품 내에 포함된 유가금속 또는 유해금속자원의 재활용 기술 중 치환법(Cementation)은 상대적으로 높은 기전력을 나타내는 금속을 첨가함으로써 용액 내의 금속이온을 침전시키는 전기화학적 석출 방법으로 금속이온의 회수기술 중 경제적이며 효율적인 재활용 기술 중 하나로 부각되고 있다. 본 연구에서는 폐니켈-카드뮴 전지 내에 포함된 카드뮴 회수의 최적 조건을 선정하기 위하여 0.1 M 황산카드뮴($CdSO_4$) 용액과 Ni-Cd 침출액에서 pH, 온도, 아연의 입자크기, 아연의 투입량을 변수로 하여 실험을 진행하였다. 니켈과 카드뮴이 포함된 용액에서 아연의 입자크기와 온도가 중요한 변수로 작용하였으며, 700 um의 아연을 이용하여 $25^{\circ}C$의 온도를 나타내는 용액에서 카드뮴 대비 2.6배의 화학당량 비의 아연을 투입할 때 최적의 카드뮴의 회수율 및 니켈의 회수율을 최소화할 수 있는 조건임을 확인하였다.

Atypical triggers in trigeminal neuralgia: the role of A-delta sensory afferents in food and weather triggers

  • Koh, Wenjun;Lim, Huili;Chen, Xuanxuan
    • The Korean Journal of Pain
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    • 제34권1호
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    • pp.66-71
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    • 2021
  • Background: Trigeminal neuralgia is a debilitating craniofacial pain syndrome that is characterized by paroxysms of intense, short-lived electric shock-like pains in the trigeminal nerve distribution. Recently, the presence of triggers has become one of the key diagnostic criteria in the 3rd edition of the International Classification of Headache Disorders. Light touch is the most common trigger, however other non-mechanical triggers, such as cold weather and certain foods, have been thought to provoke trigeminal neuralgia anecdotally. We aimed to characterize the prevalence and characteristics of these atypical triggers. Methods: We conducted a retrospective, cross-sectional study of atypical triggers in trigeminal neuralgia patients seen in a tertiary pain clinic in Singapore. Patients were recruited via clinic records, and study data were identified from physician documentation. Results: A total of 60 patients met the inclusion criteria. Weather triggers were observed in 12 patients (20%), of which five patients (8%) reported strong winds, 4 patients (7%) reported cold temperatures, and 3 patients (5%) reported cold winds as triggers. Fifteen patients (25%) had a specific food trigger, of which 10 patients (17%) reported hard or tough food, 5 patients (8%) reported hot/cold food, 4 patients (7%) reported spicy food, and 2 patients (3%) reported sweet food as triggers. Conclusions: Although trigeminal neuralgia is most commonly triggered by mechanical stimuli, atypical triggers such as cold temperatures and certain foods are seen in a significant proportion of patients. These atypical triggers may share a common pathway of sensory afferent Aδ fiber activation.