• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.26 no.2
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• pp.75-90
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• 1996

The purpose of this study was to observe microscopic change of salivary gland tissue, which is a cause of xerostomia in diabetic condition; for this target, the author injected streptozotocin 0.1ml/100 gm b.w. on the rat, Sprague Dawley, to induce diabetes, and then observed microscopic changes in parotid gland tissue using light microscopy and electron microscopy. The results were as follows : 1. Parotid gland tissue of the diabetic rat was atrophied or degenerated in lapse of experimental time, but began to repair from 14 days after diabetic induction. 2. In the basal lamina of the vessel of parotid gland tissue in the diabetic rat, lamina lucida was discontinued and lamina densa was increased in thickness, but the number of capillary was gradually increased and dilated. 3. In acinic and intercalated ductal cells of parotid gland in the diabetic rat, changes of mitochondria, RER, secretory granule, free ribosome were prominent. In conclusion, the present study demonstrated that degenerative changes of the parotid gland tissue were due to not completely thickening of the basal lamina of vessels, but many other causal factors, because thickness of the basal lamina of vessels was not related with degenerative changes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.4
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• pp.205-208
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• 1998

Silica bodies (phytoliths) are becoming of wide use for pedology, archaeology, paleobotany and paleoecology in botany. This study investigated morphological differences of silica bodies in the lamina of wild, indica type, and japonica type rice. Phytoliths in the epidermis of lamina showed noticeable difference among tested plants. Besides, there were also significant differences in the shape and distribution of the silica bodies around stomata and trichomes. Silica bodies in the lamina of the rice plants could be used to classify subspecies of Oryza genus.

• Journal of Ship and Ocean Technology
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• v.1 no.2
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• pp.11-18
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• 1997

The leading edge of a low-drag super-cavitating foil has been made to be thick enough by using a point drag which is supposed to be a linear model of the Kirchhoff lamina. In the present paper, the relation between the point drag and the Kirchhoff lamina is made clear by analyzing the cavity drag of both models and the leading edge radius of the point drag model and the lamina thickness of Kirchhoff\`s profile K. The matched asymptotic expansion is effectively made use of in designing a practical super-cavitating fool which is not only of low drag but also structurally sound. Also it has a distinct leading edge cavity separation point. The cavity foil shapes of trans-cavitating propeller blade sections designed by present method are shown.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.6 no.1
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• pp.51-58
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• 1976

The study was performed to investigate the thickness of lamina dura of the human teeth in normal condition, which obtained from the intraoral roentgenograms of the 1200 cases taken by bisecting technique. All films were divided into the different ages, the different sexes, and the different location of the different teeth. The obtained results were as follows: 1. With advancing age in both sexes, the lamina dura tends to become thinner as following. (equation omitted) 2. Generally, the alveolar crest is the thickest among the root surfaces, and apex, midroot followed, and the average thickness of the posterior teeth is thicker than that of the anterior teeth. 3. The mean value of the whole maxillary teeth is larger than the one of the whole mandibular teeth. 4. On the whole cases, the differences of male and female is about 0.019㎜, which is not a significant differences.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.11 no.1
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• pp.67-74
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• 1981

The study was performed to investigae the thickness of lamina dura of the human teeth in periodontal disease, which obtained from the intraoral roentgenograms of the 122 cases taken by bisecting technic. All films were divided into the different ages, the different sexes, and the different location of the different teeth. The obtained results were as follows: 1. Compared with the normal teeth, the thickness of lamina dura in periodontal disease is in creased in all of different ages, sexes and teeth. (equation omitted) 2. Generally, the alveolar crest portion is the thickest among the root surfaces, and midroot, apex followed, and the average thinckness of the posterior teeth is thicker than that of anterior teeth. The mean value of the whole maxillary teeth is almost same as that of mandibular teeth. On the whole cases, the differences of male and female is about 0.01㎜, which is not a significant differences.

• Current Optics and Photonics
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• v.5 no.1
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• pp.23-31
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• 2021

We propose a wheel screen type Lamina 3D display, which realizes a 3D image that can satisfy the accommodation cue by projecting volumetric images encoded by varying polarization states to a multilayered screen. The proposed system is composed of two parts: an encoding part that converts depth information to states of polarization and a decoding part that projects depth images to the corresponded diffusing layer. Though the basic principle of Lamina displays has already been verified by previous studies, those schemes suffered from a bottleneck of inferior resolution of the 3D image due to the blurring on the surfaces of diffusing layers in the stacked volume. In this paper, we propose a new structure to implement the decoding part by adopting a form of the wheel screen. Experimental verification is also provided to support the proposed principle.

• Journal of Korean Neurosurgical Society
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• v.54 no.1
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• pp.25-29
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• 2013

Objective : To clarify the landmark for deciding the entry point for C1 lateral mass screws via the posterior arch by using 3-dimensional (3D) computed images. Methods : Resnick insisted that the C1 posterior arch could be divided into pure posterior and lateral lamina (C1 pedicle). Authors studied where this transition point (TP) is located between the posterior lamina and the C1 pedicle and how it can be recognized. The 3D computed images of 86 cadaver C1s (M : F=45 : 41) were used in this study. Results : The superior ridge of the C1 posterior arch had 2 types of orientation. One was in the vertical direction in the C1 posterior lamina and the other was in the horizontal direction in the C1 pedicle. The TP was located at the border between the 2 areas, the same site as the posterior end of the groove of the vertebral artery. On posterior-anterior projection, the posterior arch was sharpened abruptly at TP. We were unable to identify the TP in 6.4% of specimens due to complete or partial osseous bridges. A total of 93.8% of the TP were located between the most enlarged point of the spinal canal and the medial wall of the vertebral artery. Conclusion : The anatomic entry zone of C1 lateral laminar screws was clarified and identified based on the TP by using preoperative 3D computed images.

• Journal of the Korean Wood Science and Technology
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• v.32 no.4
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• pp.46-51
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• 2004

The objective of this study was to evaluate the applicability of high temperature drying to pitch pine (Pinus rigida) lumber, especially intended for use as lamina of structural glued laminated timber (glulam), to enhance the efficient utilization and provide added-value to that species. The high temperature schedule and drying procedures utilized were shown to be reasonable for drying glulam lamina due to the occurrence of small moisture gradients, minimal residual drying stress, and low warpage. Through preliminary tests, it was confirmed that residual resin at lamina surfaces did not adversely affect the gluing process. However, quantitative analysis of resin is required for developing a method to constrain the occurrence of pitch trouble with respect to decreasing long-term adhesive and finish durability of glulam in use after manufacturing. The final moisture content of high temperature dried lamina was much lower than target moisture content and discoloration was more severe than anticipated. In a further study, it will be necessary to determine the optimal drying conditions, such as temperature, humidity, drying time, and top load restraint level, which could best control discoloration, warpage, and moisture content of the lamina, while minimizing fuel expense.

• The Journal of Korean Medicine
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• v.23 no.3
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• pp.200-210
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• 2002

Objectives: Dojeckjiyu-tang has been used to treat Hwaseol & Jeokri. The object of this study is examination of the treatment effect of Dojeckjiyu-tang for ulcerative colitis of the mouse descending colon. Methods and Materials : Twenty-one rats were divided into 3 groups and treated as follows: the control group was untreated mice. The UCE group was ulcerative colitis elicited mice. The DJT group was Dojeckjiyu-tang treated mice after ulcerative colitis elicitation. The groups were examined with common morphology, paneth cells in intestinal crypt, absorptive cells and goblet cells in epithelium, cell division in mucose, COX-1 as mucosal protector, COX-2 (which appears to play an important role in inflammation), IL-2R-, ICMA-1-inducing cellular immuno-chainreaction, and the distribution of apoptotic cells. Results: 1. The morphology of colonic mucosa from UCE mice: the disappearance of epithelium and intestinal propria in hemorrhagic erosions were seen, but in the morphology of colonic mucosa from DJT-treated mice, the configuration of epithelium and intestinal propria were the same as normal. 2. The distribution of goblet cells and absorptive cells with microvilli in intestinal propria from UCE mice: a noticeable decrease of goblet cells and absorptive cells with microvilli were seen, but with the distribution of goblet cells and absorptive cells with microvilli in intestinal propria from DJT -treated mice, the configuration of goblet cells and absorptive cells with microvilli were the same as normal. 3. The immunohistochemical stain for BrdD in colonic mucosa and COX-1 in lamina propria from UCE mice: BrdU positive cells and COX-1 positive cells in the region of hemorrhagic erosion disappeared, but in the immunohistochemical stain for BrdU in colonic mucosa and COX-1 in lamina propria from DIT-treated mice, BrdU positive cells and COX-1 positive cells were seen. 4. The immunohistochemical stain for COX-2 in lamina propria, IL-2R-in lamina propria, intestinal propria and submucosa and ICMA-1 in intestinal propria and submucosa from DCE mice: a noticeable increase COX-2, IL-2R-, ICMA-1 positive cells were seen, but in the immunohistochemical stain for COX-2 in lamina propria, IL-2R-in lamina propria, intestinal propria and submucosa and ICMA-1 in intestinal propria and submucosa from DJT-treated mice, a numerical decrease of COX-2, IL-2R-, ICMA-1 positive cells was observed. 5. The distribution of apoptotic cells in epithelium and lamina propria from UCE mice: a noticeable increase of apoptotic cells in region of hemorrhagic erosion was seen, but in the distribution of apoptotic cells in epithelium and lamina propria from DJT-treated mice, a remarkable decrease of apoptotic cells was seen. Conclusions: According to the above results, Dojeckjiyu-tang has a moderate effect on ulcerative colitis in descending colon.

• Applied Microscopy
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• v.17 no.1
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• pp.47-64
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• 1987

Morphological difference of the renal glomerulus at different age groups have been studied in young (three month-old), adult (twelve month-old) and old (thirty month-old) Fisher strain 344 rats. Pieces of the tissues were taken from renal corticies prefixed with 2.5% glutaraldehyde-1.5% paraformaldehyde (0.1 M Millonig's phosphate buffer, pH 7.3), following by post-fixation with 1% osmium tetroxide (0.1 M Millonig's phosphate buffer, pH 7.3) and embedded within Araldite. The ultrathin sections contrasted with uranyl acetate and lead citrate were observed under a JEM 100CX electron microscope. The mean thickness of glomerular basal lamina and Bowman's capsule were determined by measuring the thinnest portion of basal lamina, and by taking the average of 50 readings from electron micrographs at different ages. The numerical changes of the slit pores were compared based upon the numbers over the length of 10um of glomerular basal lamina. The results were as follow: 1. The thickness of glomerular basal lamina is increased during aging; 140.4 nm in young rats, 270.0 nm in adult ones, and 437.8 nm in old ones. 2. The thickness of basal lamina of parietal cells of Bowman's capsule is 187.5 nm in young rats, 914.0 nm in adult ones, and 2850.0 nm in old ones. 3. The numbers of the slit pores of basal lamina are reduced during aging, 30.3 slit pores/$10{\mu}m$ in adult ones, and 24.2 slit pores/$10{\mu}m$ in old ones. 4. Accumulation of dense intracytoplasmic filamentous material in the parietal cells of Bowman's capsule is increased in the vicinity of the basal lamina during aging. The proximal tubule-like epithelial cell in Bowman's capsule is observed at one glomerulus in a young rat. 5. The endothelial cells are edematous and form balloon-like structure protruding into capillary lumen in young and old rats. 6. Cytoplasm of the podocyte shows a variety of alteration during aging, such as swelling of mitochondria and of endoplasmic reticulum, and increase of microtubules, microfilaments, lysosomes and lamellated myelin structures, etc. Accumulation of dense intracytoplasmic material in the foot processes is increased in the vicinity of the basal lamina during aging. The podocytic membrane-like structures are seen in young and o]d rats. 7. The mesangial matrices and mesangial cells are increased during aging, and slight swelling of endoplasmic reticulum and Golgi cisternae in young and old rats.