• Korean Chemical Engineering Research
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• v.49 no.1
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• pp.47-55
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• 2011

The optimum mold design and the optimum process condition were constructed upon executing process simulation of rubber injection molding with the commercial CAE program of MOLDFLOW (Ver. 5.2) in order to solve the process-problems of K company relating to cracks, which occurs at the inner cavity wall of C. V. joint boots. As a result it was confirmed that the real cracks occurs at the exactly same position of the cavity as exhibits the defects of weld and meld line and unsatisfactory curing according to the result of simulation. In order to prevent the occurrence of weld and meld line at the defect-position, the location of gate was altered to the optimum position of the cavity. Consequently the filling pattern was established to minimize the degree of the melt-fronts confronting or the melt-flows melding to prevent the occurrence of weld and meld line at the defect-position. It was observed that both gate-positions to maximize the degree of the formation of weld and meld line and air traps are located, respectively, in opposite direction each other with reference to the optimum gate position. In addition, the temperature of mold was raised by $10^{\circ}C$ and maintained at $170^{\circ}C$ for satisfactory curing.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1981.05a
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• pp.39.3-40
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• 1981

Concerning the pathogenesis of acquired cholesteatoma in attic, there has been postulated theories by immigration from the Shrapnell's portion of the tympanic membrane, posterosuperior quardrant of the deep meatal skin and invagination of the margin of the central perforation. Otherwise, squamous metaplasia of the epithelium lining the middle ear cleft has been supported as a possible cause of cholesteatoma. Clinically, there has been known of the facts that cholesteatoma is formed in the attic but the pathogenesis concerning the acquired cholesteatoma is not still exactly reported. Recently, authors analyzed 170 cases of cholesteatomatous middle ear performed the operation to the middle ear cleft. On the operation finding, when the primary focus of the cholesteatoma was in the attic, we observed two types of perforation, marginal and central perforation in the Shrapnell's portion, and retraction to the Prussak's space, bony defect on the Rivinus notch. Among 36 cases of the cholesteatoma, the perforation of the Shrapnell's portion are 5 cases. Bony defect on the Rivinus notch and marginal perforation on the posterosuperior quadrant of the Shrapnell's portion are 21 cases. Among these cases, 3 cases are combined with central perforation of the Shrapnell's portion. Conclusively, the reasons that cholesteatoma is favorable site in the attic: 1) Excretion of the inflammatory discharge in the attic is difficult because of the distance of the E-tube. 2) The Shrapnell's portion has less collagen fiber than the pars tensa and it is thin because the elastic fibers are rich in it. It is easy to retract within the Prussak's space to the cases of keratinizing hyperplasia. 3) The epidermis attached at the Rivinus notch of the superior portion on the Shrapnell's portion is invaginated through the destructed bony wall of the Rivinus notch and the margin of the tympanic membrane in the response to the keratinizing hyperplasia.

• Journal of Periodontal and Implant Science
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• v.26 no.3
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• pp.605-624
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• 1996

Various bonegraft materials and the technique of guided tissue regeneration have been used to regenerate lost periodontal tissue. Calcium sulfate has been known as a bone graft material because of good biocompatibility, rapid resorption and effective osteoinduction. It has been known that calcium sulfate works as a binder to stabilize the defect when it is used with synthetic graft materials. The effects on the regeneration of pericxiontal tissue were studied in dogs after grafting 3-wall intrabony defects with calcium carbonate and calcium sulfate and covering with calcium sulfate barrier. The 3-wall intrabony defectstdmm width, 4mm depth, 4mm length) were created in anterior area and treated with flap operation alone(contol group), with porous resorbable calcium carbonate graft alonetexperirnental group 1), with calcium sulfate graft alonetexperimental group 2) and with composite graft of 80% calcium carbonate and 20% calcium sulfate with calcium sulfate barriertexperimental group 3). Healing responses were histologically observed after 8 weeks and the results were as follows: 1. The alveolar bone formation was $0.59{\pm}0.19mm$ in the control group, $1.80{\pm}0.25mm$ in experimental group 1, $1.61{\pm}0.21mm$ in experimental group 2 and $1.94{\pm}0.11mm$ in experimental group 3 with statistically significant differences between control group and all experimental groups(P<0.05). There were statistically significant differences between experimental group 1 and group 2 (P<0.05). 2. The new cementum formation was $0.48{\pm}0.19mm$ in the control group. $1.72{\pm}0.26mm$ in experimental group 1, $1.43{\pm}0.17mm$ in experimental group 2, $1.89{\pm}0.15mm$ in experimental group 3 with statiscally significant differences between control group and all experimental groups (p<0.05). There were statistically significant differences between experimental group 1 and group 2, and between experimental group 2 and group 3(P<0.05). 3. The length of junctional epithelium was $1.61{\pm}0.20mm$ in the contol group, $0.95{\pm}0.06mm$ in experimental group 1, $1.34{\pm}0.16mm$ in experimental group 2, $1.08{\pm}0.11mm$ in experimental group 3 with statiscally significant differences between control group and experimental group 1. and btween control group and experimental group 3(p<0.05). There were statistically significant differences between experimental group 1 ,and group 2, and between experimental group 2 and group 3(P<0.05). 4. The connective tissue adhesion was $1.67{\pm}O.20mm$ in the control group, $1.33{\pm}0.24mm$ in experimental group 1. $1.23{\pm}0.16mm$ in experimental group 2, $1.08{\pm}0.14mm$ in experimental group 3 with statistically significant differences between control group and all experimental groups(p<0.05). There were nostatistically significant differences between all experimental groups. As a result, epithelial migration was not prevented when calcium sulfate was used alone, but new bone and cementum formation were enhanced. Epithelial migration was prevented and new bone and cementum formation were also enhanced when calcium carbonate was used alone and when both calcium carbonate and calcium sulfate were used.

• Journal of Medicine and Life Science
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• v.21 no.3
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• pp.121-126
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• 2024

Disseminated tuberculosis (TB), resulting from the hematogenous spread of tubercle bacilli, typically affects immunocompromised individuals, such as those infected with the human immunodeficiency virus. However, risk factors in immunocompetent populations are not well understood. Here, we report a rare case of disseminated TB with CD4+ T-cell depletion in a previously healthy 35-year-old man. The patient presented with a 2-month history of intermittent gross hematuria, dysuria, loose stools, and weight loss. His medical history was unremarkable except for a herpes zoster infection 4 years prior to presentation. Laboratory tests revealed microscopic hematuria and pyuria; however, the urine culture was negative. Urine specimens tested positive for TB-polymerase chain reaction. Abdominal computed tomography revealed a focal filling defect in the left kidney, segmental wall thickening of the terminal ileum, and multiple enlarged lymph nodes with central necrosis. Chest computed tomography revealed active pulmonary TB. Colonoscopy confirmed intestinal TB in the terminal ileum and ileocecal valve, with positive TB-polymerase chain reaction results from sputum and ileal ulcer tissue. The patient was diagnosed with disseminated TB and was treated with standard anti-TB drugs. Although the human immunodeficiency virus test results were negative, the patient's CD4+ T-cell count was significantly low (278/μL). Follow-up tests after 1 month showed negative TB cultures; however, the patient's CD4+ T-cell depletion persisted, with counts remaining low after 1 year. This case highlights the rare occurrence of disseminated TB in immunocompetent individuals with CD4+ T-cell depletion and emphasizes the importance of CD4+ T-cell assessment in healthy patients presenting with disseminated TB.

• Journal of Periodontal and Implant Science
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• v.32 no.3
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• pp.565-576
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• 2002

The ultimate goal of periodontal therapy is the regeneration of periodontal tissue which has been lost due to destructive periodontal disease. To achieve periodontal regeneration, various kinds of methods have been investigated and developed, including guided tissue regeneration and bone graft. Bone graft can be catagorized into autografts, allografts, xenografts, bone substitutes. And materials of all types have different biological activity and the capacity for periodontal regeneration, but ideal graft material has not been developed that fits all the requirement of ideal bone graft material. Intensive research is underway to identity, purify, synthesize a variety biologic modulators that may enhance wound healing and regeneration of lost tissues in periodontal therapy. The present study evaluates the effects of ABM/P-15 on the periodontal regeneration in intrabony defects of human. We used thirty four 2-wall or 3-wall osseous defects in premolars and molars of chronic peridontitis patient that have more than 5mm pockets and more than 3mm in intrabony defect. 12 negative control group underwent flap procedure only, 11 positive control group received DFDBA graft with flap procedure, and 11 experimental group received ABM/P-15 graft with flap procedure. The changes of probing pocket depth, loss of attachment and bone probing depth following 6months after treatment revealed the following results: 1. The changes of probing pocket depth showed a statistically significant decrease between after scaling and 6months after treatment in negative control(2.0${\pm}$0.9mm), positive control(3.0${\pm}$0.9mm), and experimental group (3.4${\pm}$1.5mm) (P<0.01). Significantly more reduction was seen in experimental group compared to negative control group (P<0.05). 2. The changes of loss of attachment showed a statistically significant decrease between after scaling and 6months after treatment in positive control(2.0${\pm}$0.6mm), and experimental group (2.2${\pm}$l.0mm) except negative control group(0.1${\pm}$0.7mm) (P<0.01). Significantly more reduction was seen in both experimental and positive control group compared to negative control group(P<0.05). 3. The changes of bone probing depth showed a statistically significant decrease between after scaling and 6months after treatment in positive control(2.7${\pm}$l.0mm), and experimental group (3.4${\pm}$1.3mm) except negative control(0.l${\pm}$0.9mm) (9<0.01). Significantly more reduction was seen in both experimental and positive control group compared to negative control group (P<0.05). The results suggest that the use of ABM/P-15 in the treatment of periodontal intrabony defects can reduce loss of attachment and bone probing depth more than flap operation only. It suggests that ABM/P-15 may be an effective bone graft material for the regeneration of periodontal tissue in intrabony defects.

• The Korean Journal of Nuclear Medicine
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• v.26 no.2
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• pp.265-273
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• 1992

Rest gated blood pool scan (Rest GBP scan) and dipyridamole $^{99m}Tc-MIBI$ SPECT were Performed in 34 patients with or suspected coronary artery disease. Both studies were performed within $2\sim32$ days (mean 8.1 days). A significant correlation was present between left ventricular ejection fraction (r= -0.7356, p<0.001) and peak ejection rate and peak filling rate in rest GBP scan and perfusion defect in MIBI SPECT. And there were acceptable correlations (0.05$26.2{\pm}10.8%$, severe hypokinesia, akinesia or dyskinesia in 16 regions: $78.2{\pm}23.7$, p<0.001). These data indicate there is a significant coupling between the degree of myocardial perfusion and the myocardial functional change in coronary artery disease.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.6
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• pp.431-436
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• 2009

There are five principal causes for excessive bleeding in the immediate postextraction phase ; (1) Vascular wall alteration (wound infection, scurvy, chemicals, allergy) (2) Disorders of platelet function (genetic defect, drug-aspirin, autoimmune disease) (3) Thrombocytopenic purpuras (radiation, leukemia), (4) Inherited disorders of coagulation (hemophilia, Christmas disease, vitamin deficiency, anticoagulation drug-heparin, coumarin). If the hemorrhage from postextraction wound is unusually aggressive, and then dehydration and airway problem are occurred, the socket must be packed with gelatine sponge(Gelfoam) that was moistened with thrombin and wound closure & pressure dressing are applied. The thrombin clots fibrinogen to produce rapid hemostasis. Gelatine sponges moistened with thrombin provide effective coagulation of hemorrhage from small veins and capillaries. But, in dental alveoli, gelatine sponges may absorb oral microorganisms and cause alveolar osteitis (infection). This is a case report of bleeding control by continuous rubber strip & iodoform gauze drainage (without gelfoam packing) of active bleeding infection sites of three teeth extraction wounds in a 46-years-old female patient with advanced liver cirrhosis.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.154-154
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• 2003

A stoichiometric mixture of evaporating materials for CuGaSe2 single crystal thin films was prepared from horizontal electric furnace. Using extrapolation method of X-ray diffraction patterns for the polycrystal CuGaSe2, it was found tetragonal structure whose lattice constant at and co were 5.615 ${\AA}$ and 11.025 ${\AA}$, respectively. To obtain the single crystal thin films, CuGaSe2 mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the hot wall epitaxy (MWE) system. The source and substrate temperatures were Slot and 450$^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (UXD). The carrier density and mobility of CuGaSe2 single crystal thin films measured with Hall effect by van der Pauw method are 5.0l${\times}$10$\^$17/ cm$\^$-3/ and 245 $\textrm{cm}^2$/V$.$s at 293K, respectively. The temperature dependence of the energy band gap of the CuGaSe2 obtained from the absorption spectra was well described by the Varshni's relation, Eg(T) = 1.7998 eV - (8.7489${\times}$10$\^$-4/ eV/K)T$^2$/(T + 335 K. After the as-grown CuGaSe2 single crystal thin films was annealed in Cu-, Se-, and Ca-atmospheres, the origin of point defects of CuGaSe2 single crystal thin films has been investigated by the photoluminescence(PL) at 10 K The native defects of V$\_$CU/, V$\_$Se/, Cu$\_$int/, and Se$\_$int/ obtained by PL measurements were classified as a donors or accepters type. And we concluded that the heat-treatment in the Cu-atmosphere converted CuGaSe2 single crystal thin films to an optical n-type. Also, we confirmed that Ga in CuGaSe2/GaAs did not form the native defects because Ga in CuGaSe2 single crystal thin films existed in the form of stable bonds.

• Clinical and Experimental Pediatrics
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• v.52 no.12
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• pp.1388-1391
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• 2009

Poland syndrome is characterized by unilateral absence or hypoplasia of the pectoralis muscle and variable degree of ipsilateral hand anomalies. Mobius syndrome is a congenital neurological disorder characterized by complete or partial facial paralysis. Although the pathogeneses of these diseases are not well-characterized, diminished blood flow to the affected side is thought to play a role. A male infant weighing 2.670 g was born at 38+3 weeks of gestation with left facial paralysis, left chest wall defect with dextrocardia, and symbrachydactyly between the second and third fingers. The combination of Poland-Mobius syndrome is rare, and only 2 cases associated with dextrocardia have been reported worldwide. Here, we report the first case of Poland-Mobius syndrome associated with dextrocardia in Korea.

• Advances in pediatric surgery
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• v.2 no.1
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• pp.26-32
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• 1996

To understand the current status of neonatal surgery in Korea, a survey was made among the 27 members of Korean Association of Pediatric Surgeons. Response rate among surgeons was 78 percent, eighteen hospitals participated in this study. Five hundred and three cases of neonatal surgical patients were analyzed. In Korea, about 50% of cases were treated at the hospital in the capital city area. Regional number of patients were closely related to the regional population. Imperforate anus(19%), atresia/stenosis of gut(12%), and Hirschsprung's diseases(12%) were sitting at the top in the list. Majority of operation was done within the first week of life, especially during the first 24 hour period. Eighty per cent was major or so called index cases. Mortality in so-called index cases was 17%. High mortality was observed in patients with diaphragmatic hernia(47%), gastrointestinal perforation(65%) and esophageal atresia(28%). Low birth weight babies showed higher mortality in gastrointestinal perforation, esophageal atresia and abdominal wall defect. These were compared to 1993 survey of Japanese Society of Pediatric Surgeons.