• Journal of the Korean Ceramic Society
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• v.41 no.12 s.271
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• pp.921-928
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• 2004

Calcium phosphate powders have been prepared by using $Ca(OH)_2\;and\;H_{3}PO_4$ solution under various conditions such as pH, calcination temperature, and reaction time. ${\beta}-TCP({\beta}-tricalcium phosphate)$and HAp(hydroxyapatite) were synthesized at pH=5.21 and pH > 7.62, respectively. From XRD results, $Ca(OH)_2\;and\;H_{3}PO_4$ solution reacted quickly to form HAp, which was structurally stable up to 16h. Calcination temperature having good crystallinity is revealed to be at $1200^{\circ}C$. SEM analysis showed that ${\beta}-TCP$ and HAp with needle type were synthesized at pH 5.21 and pH 7.62, respectively. However, at pH 9.16, tiny and homogeneous HAp having sphere was prepared and rearranged to show needle morphology. HAp synthesized at pH 9.16 was utilized as bonechina body and calcined. The sample was analyzed its crystallinity, water absorbtion, color, and shape to check physical properties.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.146-146
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• 1999

BN은 천연에는 존재하지 않는 인공재료로서 특히 섬아연광형 질화붕소인 c-BN은 다이아몬드 다음가는 고경도, 높은 열전도도를 가지고 있을 뿐만 아니라 다이아몬드와는 달리 철계금속에 대해 화학적으로 매우 안정하기 때문에 다이아몬드의 응용이 매우 제한되고 있는 철강제품의 가공공구, 내마모 코팅재료로서 주목받고 있는 차세대 박막재료이다. 최근 c-BN박막 합성에 관한 많은 연구결과들이 보고되었는데 대부분의 연구자들이 성장하는 박막 표면에 입사되는 이온 에너지 및 유량이 c-BN 합성에 중요한 인자이며, 합성된 박막은 sp2결합층(h-BN)과 sp3결합층(c-BN)이 혼합되어 있음을 알 수 있다. 그러나 기존의 이온빔보조 합성법(IBAD) 공정에서는 입사빔과 증착물질이 공간적, 시간적으로 일치되는 경우에만 입사빔의 운동에너지가 증착공정에 기여하기 때문에 입사빔의 정밀한 에너지 조절이 어렵게 된다. 그러나 음이온 빔 직접 증착법에서는 입사이온빔 자신이 운동에너지를 운반하기 때문에 에너지 조절이 정밀할 뿐만 아니라 이를 통해 BN 박막의 상 및 성장거동을 조절할 수 있게 된다. 본 연구에서는 음이온 직접 증착법을 이용하여 c-BN박막을 합성하고 이의 초기성장층의 성장거동을 조사하였다. 증착시 음이온 빔의 에너지가 Bn 박막의 결정성에 미치는 영향을 알아보기 위하여 100~500eV의 보론 음이온빔을 조사하였으며 질소원으로는 낮은 낮은 에너지 범위의 질소이온을 동시에 공급하였다. FRIR 분석결과, 보론 이온의 에너지가 증가하면 cubic 상의 분율이 증가하였으며 증착된 박막은 15nm 두께의 sp2결합층이 먼저 성장한후 sp3결합층으로의 상전이가 일어났다. 질소이온빔의 에너지는 100eV 일 때 최대 cubic 함량과 두께를 보였으며 그 이상의 에너지에서는 c-BN 박막을 sputter시켰다. AFM 관찰결과, h-Bn층은 날카롭고 방향성을 가진 침상이었으며 c-BN 층은 atomically smooth 한 표면을 관찰할 수 있었다.

• Journal of the Korean Orthopaedic Association
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• v.54 no.5
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• pp.411-417
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• 2019

Purpose: To compare the clinical outcomes of single injection adductor canal block (SACB), continuous adductor canal block (CACB), and the concomitant use of transdermal buprenorphine after total knee arthroplasty (TKA). Materials and Methods: A total of 125 patients who underwent TKA were divided into three groups and the clinical results were retrospecitively compared. Group I was comprised of patients with pain controlled by SACB (n=41). Group II consisted of patients with pain controlled by both SACB and transdermal buprenorphine (10 ㎍/h) (n=44). Group III contained patients with pain controlled by CACB (n=40). The visual analogue scale (VAS) was used as the pain control indicator and the patients were measured on a VAS for resting on the bed (VAS-Rest) at 12 hours, 24 hours, and 48 hours after surgery. The VAS while doing continuous passive motion (VAS-CPM) on the first and second postoperative day was also measured. In addition, the total amount of medications used (Butopahn, Tridol, and Ketorac) for the intravenous patient controlled analgesia (PCA) was counted for 48 hours after surgery. As the indicator of the functional recovery outcome, the incidence of nausea and vomiting was observed for 48 hours after surgery. The maximum knee joint flexion range and maximum walking distance on the first and second postoperative day, and the total length of stay at the hospital were compared. Results: The VAS-Rest was similar in the three groups at 12 hours after surgery, but at 24 hours and 48 hours after surgery, group II and III a lower VAS-CPM and total amount of medications used for PCA than group I (p<0.05). The three groups showed a low incidence of nausea and vomiting, maximum knee joint flexion range, and similar walking distance and total length of stay at the hospital. Conclusion: The combination of SACB and transdermal buprenorphine has great pain control effect initially. On the other hand, it is not associated with catheter complications and it is convenient to use and safety toward the renal function. Therefore, the concomitant use of SACB and transdermal buprenorphine can be an effective pain control method after TKA.

• Journal of Korean Society of Spine Surgery
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• v.25 no.4
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• pp.147-153
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• 2018

Study Design: Retrospective case series. Objectives: We retrospectively evaluated the clinical efficacy of postganglionic nerve block in symptomatic Schmorl nodules (SNs). Summary of Literature Review: SNs are common lesions that are often asymptomatic. In certain cases, SNs have been reported to cause severe axial back pain, thereby considerably impacting patients' quality of life. No consensus currently exists on the treatment of symptomatic SNs. Materials and Methods: From October 2015 to October 2017, a total of 21 patients with symptomatic SNs diagnosed by magnetic resonance imaging (MRI) that did not respond to conservative treatment after 4 weeks were included in the study. All patients received postganglionic nerve block. We evaluated effective pain relief (improvement of back pain of more than 50% compared with before the intervention) and functional improvements, assessed by visual analogue scale (VAS) and Oswestry Disability Index scores obtained at 4 hours, 4 weeks, 8 weeks, 3 months, and 6 months after the procedure. Results: Symptomatic SNs were more common at the L2-3 level, and the lower end plate was more commonly involved than the upper end plate. Eighteen of the 21 patients (85.7%) showed effective pain relief, and no deterioration was observed within the followup period. Throughout the follow-up period, the VAS remained significantly improved compared to before the procedure (p<0.05). Complications were not reported in any cases. Conclusions: Postganglionic nerve block for symptomatic SNs that do not respond to conservative treatment is a non-invasive modality for pain relief.

• The Korean Nurse
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• v.36 no.2
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• pp.73-83
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• 1997

Bed rest is recommended to prevent postlumbar puncture headaches(PLPHA), but the period of bed rest varies in the literature from 6 hours to 24 hours. In clinical practice the period of bed rest varies but nursing methods for adults and children have little difference. In Seoul National University Hospital, children have been given at least 6 hours bed rest after a lumbar puncture. Pediatric oncology patients require a lumbar puncture for an initial diagnosis, follow up treatment or administration of chemotherapeutic agent. But it is difficult for young children to lie supine or to refrain from their usual activities in any way, and unpleasant problems related to a shortage of beds often occurs during discharge or in an outpatient setting. The purpose of this study is to substantiate the preventive effect of PLPHA by the period of bed rest, to identify the other factors that influence PLPHA, and to use the nursing methods proper to children. The subjects were 65 children, ages 1-17, undergoing treatment in the children's cancer center at SNUCH during the period June 1, 1995, to Aug. 31, 1995. The team nurses asked questions about PLPHA of the parents and children in order to fill out a questionnaire. The data were evaluated by percent, t-test, Chi-square test and Mann-Whitney U test. Result; 1. There was no significant difference relating the bed rest time spent to the occurrence of postspinal headaches (t-test). 2. There was a significant risk of PLPHA in the children who were irritable before procedure and/or had experienced previous PLPHA(p<0.05, ${x^2}-test$). 3. The following factors were not found to be associated with increased risk of PLPHA: previous puncture experience, giving analgesics, the choice of puncturist, inpatient/outpatient status, gauge of needle, purpose, the amount of CSF removed, gender, diagnosis, the number of peripheral WBCs, previous lumbago experience after LP, position after bed rest, age, the number of aural puncture at the time. A longer period of bed rest is unlikely to be more effective to prevent PLPHA and seems impractical. A shorter period will save time and effort. Perhaps it will also allay some of the fears which surround LP. So 1 hour bed rest after LP is suggested and nursing methods for emotional support should be investigated to reduce PLPH.

• The Journal of the Korean bone and joint tumor society
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• v.10 no.2
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• pp.88-95
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• 2004

Purpose: Current treatment for osteoid osteomas is usually surgical excision of the nidus. Various minimal invasive techniques have been reported to overcome the invasiveness of the surgical excision. We treated 22 patients with osteoid osteoma by percutaneous thermoablation of the nidus under computed-tomography guidance. Materials and Methods: Twenty two consecutive patients underwent CT-guided percutaneous radio-frequency thermoablation between April 1999 and May 2004. The mean age was 26.5(7~55) years. In three cases, the diagnosis was confirmed pathologically before the prodedure while the others clinically and radiologically. Computed tomography (CT)-guided percutaneous RF ablation was performed with general or spinal anesthesia. With an RF electrode, the lesion was heated to 80 or 90 degrees C for 6(3~8) minutes. Clinical success was assessed at a mean of 30(4~62) months after the procedure at out patient clinic or by telephone interview. Results: The procedure was technically successful in all cases except a complication. Patients were discharged on 1.9 days after the procedure and resumed normal activities immediately. All patients but three (86%) remained pain free during follow-up (range 4~62 months). A second thermoablation treatment relieved the recurrent symptoms in 2 patients and the remained had persistent pain without a second prodedure. Conclusion: Percutaneous thermoablation appears to be safe and effective for osteoid osteomas, and is a minimally invasive procedure alternative to surgical resection.

• Journal of Korean Orthopaedic Sports Medicine
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• v.6 no.2
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• pp.110-114
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• 2007

Purpose: This study evaluate clinical findings & management of rhabdomyolysis after strenuous activities in military police recruit. Materials and Methods: This study was carried out from June $1^{st}$, 2004 and May $23^{nd}$, 2005. The study subjects were 13 military police recruit patients who were admitted to our hospital with intractable muscle pain and swelling, and had suspicions of Rhabdomyolysis. The patients were given various blood tests (CPK, CK-MB, AST, BUN/Cr, and Electrolyte) and clinically observed. The patients were all males, and their average age was 20 $(19\sim21)$ years. Seven cases were due to push-up exercises, 5 was due to a soccer game, and 1 was due to riot control activities. The patients complained of swelling and tenderness in various parts of the extremities. Four complained of swelling and tenderness in forearm, 3 in upper arm, 1 in shoulder, and 5 in lower extremity. The diagnosis of rhabdomyolysis was made if the patient complained clinical symptom and had a blood CPK level of above 1,000 IU/L at the time of admission. Patients who took medication or had medical problem were excluded from this study. Bone scans were taken of all patients 4 hours after giving 99mTc-MDP 20mCi intravenously. Treatment was bed rest and fluid therapy. Patients who complained of excessive pain were given splint immobilization. Results: The average hospitalization day for the 13 patients was 20 days ($14\sim42$ days). Excluding one patient who exhibited ARF at time of admission, all patients showed a decrease of blood CPK below 1000 IU/L at an average hospitalization time of 8 days ($2\sim11$ days). The patient with ARF recovered after hemodialysis and fluid therapy. Conclusion: Patients complaining of swelling and severe muscle pain after excessive exercise or training should be suspicious of exercise induced rhabdomyolysis, and should be given blood tests and fluid therapy immediately.