• 제목/요약/키워드: Round Specimen

검색결과 125건 처리시간 0.023초

아말감의 표면처리에 따른 복합레진과의 전단결합 강도에 관한 연구 (A STUDY ON THE SHEAR BOND STRENGTH OF THE COMPOSITE RESIN TO AMALGAM ACCORDING TO AMALGAM SURFACE TREATMENT METHODS)

  • 박문희;조영곤;황호길
    • Restorative Dentistry and Endodontics
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    • 제18권1호
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    • pp.114-121
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    • 1993
  • The purpose of this study was to evaluate the effect on treatment methods to shear bond strength between composite resin and amalgam when the alloy surface was finished with a diamond wheel or an sandblaster. Forty round acrylic cylinders were fabricated with a diameter of 33mm and a height of 20mm to fit into the device used during shear bond strength testing. A round undercut cavity (diameter, 8mm: depth, 2.5mm) was prepared in the center of the acrylic surface and the cavity was restored using a amalgam. A total of 40 acrylic cylinders with amalgam were divided into 4 groups according to treatment method. The group treatment were as follows : Group 1 : acid etching after finishing the amalgam with diamond wheel Group 2 : no acid etching after finishing the amalgam with diamond wheel Group 3 : acid etching after sandblasting the amalgam Group 4 : no acid etching after sandblasting the amalgam The shear bond strength of composite resin bonded to amalgam of each specimen was tested with a universal testing machine at a crosshead speed of 0.5mm/min and 500kg in full scale. The results were as follow: 1. After diamond finishing, the non-acid etching group had highest shear bond strength with 7.29kg/$cm^2$ and after sandblasting, the acidetching group had lowest shear bond strength with 4.49kg/$cm^2$. 2. In both diamond finishing and sandblasting group, acid etching of the roughened amalgam surface decreased the shear bond strength. 3. The group treated with a diamond wheel had higher shear bond strength those treated with an sandblaster but there was not significanat.

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Laser Ablation에 의한 고방사성시편의 미세영역 시료채취 장치개발 (Micro Sampling System for Highly Radioactive Specimen by Laser Ablation)

  • 한선호;하영경;한기철;박양순;지광용;김원호
    • 방사성폐기물학회지
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    • 제3권1호
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    • pp.17-21
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    • 2005
  • 방사선차폐 laser ablation 시스템을 레이저, 미세영역의 영상 확인을 위한 이미지 시스템, XYZ 이동장치와 조절기, ablation chamber, manipulator 및 여러 가지 광학부품들로 구성하였다. Ablation용 레이저는 UOB 및 tircaloy 시편으로부터 효율적으로 시료를 채취할 수 있도록 266 nm(6 mJ)까지 파장 변환이 가능한 Nd:YAG 레이저를 선정하였으며, 이미지 시스템은 직경 50 $\mu$m 크기의 crater를 판별할 수 있는 200 배율 이상의 규격을 갖춘 CCD 카메라로 선정하였다. 시편 미세이동장치는 XYZ방향으로 시편이동이 가능하고 최대 이동거리가 50 mm까지 , 그리고 최소 1$\mu$m 씩 정확하게 움직일 수 있는 장치로 선정하였다. 구성된 각 단위기기들에 대하여 광학 정렬을 수행한 후, 시료채취 부위를 50 $\mu$m씩 정확하게 이동하면서 레이저로 조사시킨 시료 표면을 CCD 카메라를 통하여 관찰한 결과, 표면에 생성된 crater는 원형임을 확인함으로써 단위기기별 성능을 확인할 수 있었다.

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Morphometric Study of the Korean Adult Pituitary Glands and the Diaphragma Sellae

  • Ju, Kyo-Sung;Bae, Hack-Gun;Park, Hyung-Ki;Chang, Jae-Chil;Choi, Soon-Kwan;Sim, Ki-Bum
    • Journal of Korean Neurosurgical Society
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    • 제47권1호
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    • pp.42-47
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    • 2010
  • Objective: To investigate the morphometric characteristics of the pituitary gland and diaphragma sellae in Korean adults. Methods: Using the 33 formaline fixed adult cadavers (23 male, 10 female), the measurements were taken at the diaphragma sellae and pituitary gland. The authors investigated the relationship between dura and structures surrounding pituitary gland, morphometric aspects of pituitary gland and stalk, and morphometric aspect of central opening of diaphragma sellae. Results: The boundary between the lateral surface of pituitary gland and the medial wall of cavernous sinus was formed by the thin dural layer and pituitary capsule. The pituitary capsule adherent tightly to the pituitary gland was observed to continue from the diaphragma sellae. Mean width, length, and height of the pituitary gland were 14.3${\pm}$2.1, 7.9${\pm}$1.3, and 6.0${\pm}$0.9 mm in anterior lobes, and 8.7${\pm}$1.7, 2.9${\pm}$1.1, and 5.8${\pm}$1.0 mm in posterior lobes, respectively. Although all dimensions of anterior lobe in female were slightly larger than those in male, statistical significance was noted in only longitudinal dimension. The ratio of posterior lobe to the whole length of pituitary gland was about 27%. The mean thickness of pituitary stalk was 2 mm. The diaphragmal opening was 5 mm or more in 26 (78.8%) of 33 specimen. The opening was round in 60.6% of the specimen, and elliptical oriented in an anterior-posterior or transverse direction in 39.4%. Conclusion: These results provide the safe anatomical knowledge during the transsphenoidal surgery and may be helpful to access the possibility of the development of empty sella syndrome.

하악에 발생된 Ewing 육종의 1증례 (A CASE REPORT OF EWING′S SARCOMA OF THE MANDIBLE)

  • 박상억;박미경;최갑식
    • 치과방사선
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    • 제22권1호
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    • pp.161-168
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    • 1992
  • The authors observed a 27-year-old male patient who came to the Infirmary of Kyungpook National University Hospital who had complained of dull pain in right mandibular angle area 1 month ago. As a result of careful analysis of clinical, radiological, and histopathological findings, the authors diagnosed it as Ewing's sarcoma and obtained the results as follows: 1. In clinical examination, main clinical symptoms were continuous dull pain and gingival swelling on the 2nd and 3rd molar area of the right mandible. 2. In radiographic examination, ill-defined radiolucent area was seen on mandibular right angle area, and apparent periosteal reaction of sun-ray spicule was emanated from the lingual cortex of mandibular angle area. And computed tomograph also revealed moderate-defined 3. soft tissue mass of the same area. In histopathological examination, small round-shaped, and closely packed cells with scanty cytoplasm were observed in this specimen, and positive reaction in PAS staining was also observed.

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자궁 경부의 선암과 혼합된 신경내분비 소세포 암종 - 1 증례 보고 - (Composite Tumor of Adenocarcinoma and Small Cell Neuroendocrine Carcinoma of the Uterine Cervix -A Case Report-)

  • 박혜림;이용우;박영의
    • 대한세포병리학회지
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    • 제1권1호
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    • pp.111-120
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    • 1990
  • Small cell neuroendocrine carcinoma of the uterine cervix is a distinct subtype of cervical cancer that appears analogous to oat cell carcinoma and carcinoid tumors of the lung. It has been assumed to be derived from the neural crest via argyrophilic cells in the normal endocervix. We have recently encountered a case of small cell neuroendocrine carcinoma of the uterine cervix coexisting with adenocarcinoma which was argyrophil negative. A 66-year-old multiparous woman was admitted because of vaginal bleeding for 2 months. Cervicovaginal smear revealed several scattered clusters and sheets of monotonous small cells with some peripheral palisading in the background of hemorrhage and necrosis. Radical hysterectomy specimen revealed an ulcerofungating tumor on endocervical canal which was composed of two components. Major component of the tumor was made up of monomorphic population of small oval-shaped tumor cells arranged in sheets and partly in acinar structures or trabecular fashion. Other component was adenocarcinoma, endocervical well-differentiated type. Argyrophilia was present on the Grimelius stain and immunohistochemical studies revealed diffuse positivity to neuron-specific enolase and carcinoembryonic antigen. Electron microscopic examination showed clusters of small round to oval cells, which had a few well-formed desmosomes and several membrane-bound, dense-core neurosectetory granules.

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갑상샘 섬암종의 세침흡인 세포학적 소견 - 온전한 섬모양 구조를 가진 1예 보고 - (Fine Needle Aspiration Cytology of Insular Carcinoma of the Thyroid - Report of A Case with Intact Insulae -)

  • 최경운;김지연;이진숙;이창훈
    • 대한세포병리학회지
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    • 제14권1호
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    • pp.17-21
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    • 2003
  • Insular carcinoma of the thyroid(ICT) is an uncommon thyroglobulin-producing neoplasm, intermediate between well differentiated and anaplastic carcinoma. Only a few publications have addressed the fine needle aspiration cytologic(FNAC) findings from ICT. We experienced a case histologically diagnosed as ICT and with preoperative FNAC in a 52 - year - old woman. The FNAC displayed scanty colloid and abundant monomorphic follicular cells presented singly, in small loose aggregates, and in cohesive trabecular or acinar clusters. Intact insulae of tumor cells were also identified. Necrosis and mitosis were rare. Tumor cells showed round and monomorphic nuclei, finely granular chromatin, and inconspicuous nucleoli. When insular structure is identified in thyroid FNAC specimen, ICT should be included in the differential diagnosis. Herein we discuss and review the cytologic criteria for separation of ICT from other thyroid neoplasms.

전이성 편평 세포암종의 체액 세포학적 소견 (Effusion Cytology of Squamous Cell Carcinoma)

  • 명나혜;고재수;하창원;조경자;장자준
    • 대한세포병리학회지
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    • 제3권1호
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    • pp.12-18
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    • 1992
  • It is very rare to diagnose a squamous cell carcinoma when the carcinoma cells are observed in various body fluids. The effusion cytology of squamous cell carcinoma has not been sufficiently studied till now. We examined 10 cases of body fluid cytologic specimen diagnosed as metastatic squamous ceil carcinoma, which were selected among 2,100 body fluid cytology cases collected from 1986 to 1991. The patients had been confirmed to have primary squamous ceil carcinomas. The backgrounds of cellular aspirates were necrotic in most and the cells appeared in clusters or individually. The cell clusters showed round and smooth margins, mimicking adenocarcinoma, but in flat sheets rather than three-dimensional bails. the individual cells were most frequently Graham's 3rd-type cells, found in all cases, which were described as 1.5 times large as the parabasal cells and having small cytoplasmic rims. Other malignant squamous cells were undifferentiated cells, polygonal cells, fiber cells, and tadpole cells with decreasing order of frequency. The recognition of various features of malignant squamous cells would be helpful for the diagnosis of squamous ceil carcinoma found in effusion cytology.

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법랑질(琺瑯質)과 상아질(象牙質)의 산처리후(酸處理後)의 전자현미경(電子顯微鏡) 소견(所見)에 관(關)한 연구(硏究) (A STUDY ON ELECTRON-MICROSCOPIC FINDINGS AFTER ACID ETCHING ON ENAMEL AND DENTIN)

  • 김영해
    • Restorative Dentistry and Endodontics
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    • 제9권1호
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    • pp.115-119
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    • 1983
  • The purpose of this study was to compare the solubility of enamel and dentin to an etchant after fluoride application. Specimens were collected from extracted anterior and bicuspid and each tooth was cut into several pieces. These specimen were allocated in 7 group; 1%, 2%, 3% NaF, 1%, 8%, 20% $SnF_2$, and control group. Five specimens in each group was exposed to pre-determined fluoride solution for 3 minutes, and washed with running water. These specimens were etched by Hipol (commercial label) etchant for 30 seconds. Following are the findings obtained through S.E.M. 1. All specimens with acid etching revealed preferential removal of prism periphery leaving prism core. 2. Specimens treated with 1%, 2% NaF solution showed that the shape of prism tip was thin and sharp like a needle. The case of 3% NaF showed rather round shape at prism end. 3.1% of $SnF_2$ case showed similar findings with the control group but 8% and 20% $SnF_2$ case revealed needle shape at the prism and was less clear than NaF case. Preferential removal of prism periphery was partialy observed and un decalcified area is fused to prism forming reidge. 4. Dentine treated by fluoride compound in low concentration showed the orifice of dentinal tubule was clearly enlarged whereas in high concentration the orifice was not widened.

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22Cr-15Ni-5W 슈퍼 오스테나이트계(系) 스테인리스강(鋼)의 고온산화(高溫酸化) 및 내식성(耐蝕性)에 미치는 결정립(結晶粒) 크기의 영향(影響) (Effect of Grain Size on Corrosion Resistance and High Temperature Oxidation Behavior of 22Cr-15Ni-5W Super Austenitic Stainless Steels)

  • 김효종;이해우;이종문;강창룡
    • 동력기계공학회지
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    • 제10권3호
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    • pp.51-57
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    • 2006
  • The effect of grain size on corrosion resistance and high temperature oxidation behavior was studied in 22Cr-15Ni-5W super austenitic stainless steels for desulfurization equipment as a heat power station. In the high temperature oxidation test, oxidation rate was increased as the temperature increased from $600^{\circ}C\;to\;800^{\circ}C$. In vapor, oxidation rate was faster than that in air. Because the vapor was inhibited nucleation of $Cr_2O_3$ film. And the high temperature oxidation resistance at $600^{\circ}C{\sim}800^{\circ}C$ was excellent from all specimens and specimen of the smallest grain size was the most excellent. Because increasing of diffusion course through the grain-boundary was promoted nucleation and growth of $Cr_2O_3$ film. In the test temperature at $600^{\circ}C{\sim}800^{\circ}C$, Cr rich round particle oxide was formed in air, whereas Fe rich needle type oxide was developed in vapor.

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