• 멤브레인
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• 제17권1호
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• pp.1-13
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• 2007

분리막을 이용한 투과증발공정은 에너지 소모가 적고 설치비와 운영비면에서 우수한 효과를 볼 수 있기 때문에 증류공정을 대신할 수 있는 공정으로 주목받고 있다. 특히 석유화학공정은 공정 중에 에너지 소모가 크고, 많은 화합물들이 공비혼합물을 이루고, 새로운 공정을 설치하기 위해서는 작은 공간을 필요로 하기 때문에 투과증발공정은 증류공정을 대체할 수 있는 매우 유력한 후보이다. 벤젠/시클로헥산을 포함하는 방향족 화합물의 분리, 올레핀/파라핀 분리, 자일렌 이성질체의 분리, 반응성 단량체의 회수, 가솔린으로부터 황 화합물의 제거 등에 투과증발공정을 응용하는 많은 연구가 이루어졌으며, 상용화가 되고 있다.

• 치과방사선
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• 제21권2호
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• pp.183-197
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• 1991

After single fraction of 2, 5, 10 Gy irradiation on submandibular gland of 40 male rats, weighing 150gm, respectively, these animal were sacrificed two hours after 0.1㎎/g bromodeoxyuridine (Sigma) peritoneal injection in 1, 3, 7, 15 hours, 1, 3, 7 days after irradiation. And excised submandibular gland were fixed in Carnoy's and Bouin's solution for 2 hours. Paraffin sections were stained with H&E, and PAS for the observation of the change of salivary gland tissue, and with Feulgen for the study of the DNA distribution, and immunohistochemically stained with anti-bromodeoxyuridine (Sanbyo Co.) for detection of DNA synthetic cells in order to study the distribution of DNA synthetic cells of salivary gland tissue and endothelium after irradiation in 5 different sites of 6 slides on X 200 high power field. The results were as followings. 1. In PAS staining 3 days after 5Gy irradiation, decreased mucine secretion of serous cells were found, and 7 days after l0Gy irradiation, decreased mucine secretion of mucous cells were found. 2. In histopathologic features, degeneration of serous cells were found in 3 days after 2 Gy irradiation and there was little change in mucous cells and excretory duct cells. 3. In Feugen staining, 3 days after 2 Gy, 5 Gy irradiation, more high percentage of DNA synthetic cells were found in intercalated duct cells, striated duct cells and excretory duct cells than in BrdU staining. 4. In immunohistochemical features, DNA synethsis of serous cells and granular convoluted tubular cells abruptly decreased in early period after irradiation and showed no recovery in 7 days after irradiation but there was an increase in DNA synthesis of intercalated duct cells, striated duct cells and excretory duct cells, which have less S-phase cells comparatively, in 7 days after 2 Gy, 5 Gy irradiation. 5. In immunohistochemical features, the DNA synthesis of endothelial cells was continuously decreased after irradiation but showed slight increase in 7 days after 2 Gy and S Gy irradiation.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제18권3호
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• pp.515-527
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• 1996

The most serious problem resulting from estrogen deficiency induce osteo porosis. Recently, they make efforts to inquire a relation between hematopoietic organ and bone loss due to estrogen deficiency. Estrogen have an effect on growth and formation of skeletal system, and inhibit bone resorption under the influence of osteoblast and osteoclast, and basically inhibit the increase of hematopoietic progenitor and immune factor connected with bone resorption and prevent the osteoid formation. The purpose of this article was to observe the change of spleen and effect on hematopoietic function following estrogen administration. In this study, female rats of 150g weight was ovariectomized, after 70 days, experimental group was injected estrogen at interval of a week and sacrificed on 1, 2, 3, 4, 6 weeks. Control group was sacrificed after ovariectomy on 11, 12, 13, 14, 16 weeks without estrogen injection, and normal rats were sacrificed for harvest of spleen and femur. Paraffin sections and H&E stain was performed, and observed under light microscope. The obtained results were as follows. 1. From 11 to 12 weeks at bone marrow of control group, hematopoietic cells were decreased in comparison with normal group, and lipid infiltration was seen, and irregular bone remodelling was seen after 13 weeks. From 14 to 16 weeks, there were more decreased hematopoietic cells and lipid degeneration, and lipid degeneration of hematopoietic cells appeared. 2. All the bone marrow of experimental group, the structure of hematopoietic cells with decreased lipid infiltration was recovered from 2 weeks of estrogen adminstration and maintained to 6 weeks. 3. At spleen of control group, borders of white and red pulp was not well demarcated, and size of white pulp was decreased. 4. At spleen of experimental group, borders between white and red pulp have been well demarcated from 3 weeks of estrogen adminstration relatively, and white pulp was increased with distinct border. From above findings, we could regarded that estrogen deficiency due to ovariectomy influenced on hematopoietic cells of bone marrow and spleen, and histologic recovery of hematopoietic cells were observed after 3 weeks of estrogen adminstration even if it was not reach to normal group.

• Journal of Electrochemical Science and Technology
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• 제10권4호
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• pp.394-401
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• 2019

The unique study of TiO₂ sol-gel modified carbon paste electrode (CPE) nanocomposites have been developed for electrochemical sensor detecting fipronil pesticide compound. We develop the easy synthesized TiO₂ via a sol-gel method and modified in CPE which applied electrochemical system as cyclic voltammetry (CV) because the concentration is proportional with current peaks. We discover the TiO₂ optimal mass used of 0.1 g which is compared with 0.7 g carbon and 0.3 mL paraffin. It has high-current anodic (Ip_a) of 1.13×10³ μA and high-current cathodic (Ip_c) -0.96×10³ μA in scan rate of 0.5 V/s. The limit of detection (LOD) of fipronil has been determined of 34.0×10^-5 μM in percent recovery of 0.8%. Its high-stability for lifetime TiO₂-CPE nanocomposites was expressed for 13 days which mean that can be used for detecting fipronil pesticide.

• 한국산학기술학회논문지
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• 제20권8호
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• pp.417-424
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• 2019

포르말린을 사용한 조직 고정 방식은 우수한 세포 형태를 유지하며 장기간 조직을 보관할 수 있는 장점이 있으나, 느린 고정 시간, 유해 화학물질에 노출 및 단백질 변형 등의 단점이 있다. 본 연구에서는 마우스의 간과 신장 조직을 이용하여 포르말린 고정과 마이크로파 조사에 의한 빠른 고정을 각각 실시한 후 조직학적 검사와 단백질의 보존 상태를 측정하여 그 결과를 비교하였다. 동일 조직을 절단하여 포르말린 고정과 인산염 완충 식염수에서 마이크로파 조사에 의한 고정 과정을 동시에 실시하였으며, 파라핀 포매 조직에서 제조한 슬라이드에서 H & E와 면역화학염색을 시행하여 조직 고정의 적정성과 항원성을 검사하였다. 또한 고정 조직에서 단백질 추출 양과 질을 각각 BCA법 및 Western blotting법으로 평가하였다. H & E 염색과 면역화학염색을 수행한 결과, 적혈구의 부분적 소실을 제외하고는 마이크로파 고정 조직과 포르말린 고정 조직 간에 대등한 결과를 보였다. 특히, 마이크로파 고정 조직에서 단백질은 잘 보존된 상태로 추출되었다. 결론적으로, 마이크로파 조사를 통한 조직 고정은 포르말린 고정과 비교하여 빠른 고정시간과 우수한 단백질 회수율을 보였으며, 조직 고정의 적정성과 항원성에서도 포르말린 고정과 대등한 결과를 보여, 신속한 조직 고정이 필요한 환경에서 적용이 가능함을 제시하고 있다.

• Journal of Periodontal and Implant Science
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• 제29권3호
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• pp.483-509
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• 1999

Biodegradable barrier membrane has been demonstrated to have guided bone regeneration capacity on the animal study. The purpose of this study is to evaluate the effects of cultured calvarial cell inoculated on the biodegradable barrier membrane for the regeneration of the artificial bone defect. In this experiment 35 Sprague-Dawley male rats(mean BW 150gm) were used. 30 rats were divided into 3 groups. In group I, defects were covered periosteum without membrane. In group II, defects were repaired using biodegradable barrier membrane. In group III, the defects were repaired using biodegradable barrier membrane seeded with cultured calvarial cell. Every surgical procedure were performed under the general anesthesia by using with intravenous injection of Pentobarbital sodium(30mg/Kg). After anesthesia, 5 rats were sacrificed by decapitation to obtain the calvaria for bone cell culture. Calvarial cells were cultured with Dulbecco's Modified Essential Medium contained with 10% Fetal Bovine Serum under the conventional conditions. The number of cell inoculated on the membrane were $1{\times}10^6$ Cells/ml. The membrane were inserted on the artificial bone defect after 3 days of culture. A single 3-mm diameter full-thickness artificial calvarial defect was made in each animal by using with bone trephine drill. After the every surgical intervention of animal, all of the animals were sacrificed at 1, 2, 3 weeks after surgery by using of perfusion technique. For obtaining histological section, tissues were fixed in 2.5% Glutaraldehyde (0.1M cacodylate buffer, pH 7.2) and Karnovsky's fixative solution, and decalcified with 0.1M disodium ethylene diaminetetraacetate for 3 weeks. Tissue embeding was performed in paraffin and cut parallel to the surface of calvaria. Section in 7${\mu}m$ thickness of tissue was done and stained with Hematoxylin-Eosin. All the specimens were observed under the light microscopy. The following results were obtained. 1 . During the whole period of experiment, fibrous connective tissue was revealed at 1week after surgery which meant rapid soft tissue recovery. The healing rate of defected area into new bone formation of the test group was observed more rapid tendency than other two groups. 2 . The sequence of healing rate of bone defected area was as follows ； test group, positive control, negative control group. 3 . During the experiment, an osteoclastic cell around preexisted bone was not found. New bone formation was originated from the periphery of the remaing bone wall, and gradually extended into central portion of the bone defect. 4 . The biodegradable barrier membrane was observed favorable biocompatibility during this experimental period without any other noticeable foreign body reaction. And mineralization in the newly formed osteoid tissue revealed relatively more rapid than other group since early stage of the healing process. Conclusively, the cultured bone cell inoculated onto the biodegradable barrier membrane may have an important role of regeneration of artificial bone defects of alveolar bone. This study thus demonstrates a tissue-engineering the approach to the repair of bone defects, which may have clinical applications in clinical fields of the dentistry including periodontics.