• Imaging Science in Dentistry
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• v.32 no.1
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• pp.27-33
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• 2002

Purpose: To evaluate the influence of threshold value of computed tomography on the accuracy of rapid prototyping (RP) medical model Material and Methods : CT datas of a human dry skull were transferred from CT scanner via compact disk to a personal computer (PC). 3-dimensional image reconstruction on PC by V-works/sup TM/ 3.0 (CyberMed. Inc.) software and RP models fabrication were followed. 2-RP models were produced by threshold value of 500 and 800 selected in surface rendering process. Linear measurements between arbitrary 12 anatomical landmarks on dry skull, 3-D image model, and 2-RP models were done and compared. Thus, the accuracy of 500 RP and 800RP models was respectively evaluated. Results: There was mean difference (% difference) in absolute value of 2.27 mm (2.73%) between linear measurements of dry skull and 500 RP model. There was mean difference (% difference) in absolute value of 1.94 mm (2.52%) between linear measurements of dry skull and 800 RP model. Conclusion: Slight difference of threshold value in rendering process of 3-D modelling made a influence on the accuracy of RP medical model.

• Korean Journal of Head & Neck Oncology
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• v.9 no.2
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• pp.183-192
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• 1993

This study reports a prospective analysis of anatomical variations of recurrent laryngeal nerves during 300 thyroidectomies. During thyroidectomies for variable thyroid diseases. the course of recurrent laryngeal nerve was completely isolated from root of neck to the inferior comus of thyroid cartilage. In left side, nerve(53.7%) predominantly ran posterior to the inferior thyroidal artery(p<0.05) but in right side there was no predominant pattern. There were three nonrecurrent laryngeal nerves in the right side. About half of the cases in both sides(51.2% in right, 50.5% in left side) had one or more branches before terminating at cricothyroidal muscles. The average length of branches from inferior comus of thyroid cartilage to the origination of individual branch were l2.0mm in right side and 13.3mm in left side. In right side, majority(50.7%) of nerves ran though paratracheal space but difference did not reach the statistical but in left side, majority(88.3%) ran through tracheoesophageal groove and it was the dominant pattern(p<0.01), the overall status of passages of the nerve were relatively straight in left side(straight 87.8%, oblique 52.1%).

• Journal of the Korean Institute of Telematics and Electronics B
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• v.31B no.8
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• pp.160-171
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• 1994

The wide dynamic range and severely attenuated contrast in mediastinal area appearing in typical chest radiographs have often caused difficulties in effective visualization and diagnosis of lung diseases. This paper proposes a new adaptive image enhancement technique which potentially solves this problem and there by improves observer performance through image processing. In the proposed method image processing is applied to the chest radiograph with different processing parameters for the lung field and mediastinum adaptively since there are much differences in anatomical and imaging properties between these two regions. To achieve this the chest radiograph is divided into the lung and mediastinum by gray level thresholding using the cumulative histogram and the dynamic range compression and local contrast enhancement are carried out selectively in the mediastinal region. Thereafter a gray scale transformation is performed considering the JND(just noticeable difference) characteristic for effective image displa. The processed images showed apparenty improved contrast in mediastinum and maintained moderate brightness in the lung field. No artifact could be observed. In the visibility evaluation experiment with 5 radiologists the processed images with better visibility was observed for the 5 important anatomical structures in the thorax.

• Korean Journal of Medicinal Crop Science
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• v.8 no.4
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• pp.297-303
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• 2000

A peony is perennial plant which comes under Paeoniaceae. The anatomical differences in root and stem of Paeonia lactiflora Pallas and Paeonia obovata Maxim. are studied. The length of the vessel members of P. lactiflora Pallas is a bit longer than that of P. obovata Maxim. in the stem and the roots, and the width of the vessel members of P. lactiflora Pallas is wider than that of P. obovata Maxim. in the stem and the root. The secondary xylem in the root of P. lactiflora Pallas is discontinuos scalariform arrangement while that of P. obovata Maxim. is continuous radical arrangement.

• Journal of Veterinary Clinics
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• v.37 no.4
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• pp.180-184
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• 2020

The purpose of this study was to report the reliability and validity of oblique single-cut rotation osteotomy (OSCRO) in 3D-reconstructed canine bone models with femoral varus and torsional deformities. A healthy adult male beagle was recruited to create a 3D bone model, and this bone model was modified by using a 3D program. Fifteen bone models were constructed for this study. OSCRO simulation was performed in accordance with the plan after printing using a 3D printing machine. The anatomical lateral distal femoral angle (aLDFA), anteversion angle (AA), anatomical caudo-distal femoral angle (aCdDFA), mechanical caudo-distal femoral angle (mCdDFA) and pre- and postoperative bone length were calculated. There were no significant differences between the target values and postoperative values. In addition, the difference between pre- and postoperative bone length was small (p = 0.001). Our findings suggest that OSCRO could be an effective surgical option for MPL with bone deformities in small-breed dogs that often undergo conventional distal femoral osteotomy.

• Journal of the Korean Wood Science and Technology
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• v.32 no.3
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• pp.15-24
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• 2004

The present work was undertaken to investigate the anatomical and chemical characteristics of transgenic poplar down-regulated with antisense OMT gene. Also the distribution of lignin in transgenic poplar trees was investigated at cellular level. No visible abnormal phenotype was observed in the fibers and vessel elements of transgenic poplar. Any marked differences in the staining intensities of Wiesner and Mäule color reaction were not identified in the transgenic poplar. TEM micrographs did not show any staining intensities in the cell walls stained with KMnO₄. Interestingly, the UV spectroscopy of semi-thin sections exhibited a distinct decrease of lignin absorption at 280 nm in the vessel walls, indicating transgenic poplar wood with lower amount of guaiacyl lignin in vessel elements. Chemical composition of antisense OMT poplar was almost identical to that of wild-type poplar. Klason lignin content of transgenic poplar did not show any significant difference from that of the controls. The solid state NMR spectra revealed the transgenic poplar with only slightly more syringyl lignin than the control. The present work showed that antisense OMT gene constructed in the poplar was not enough to reduce the overall content of Klason lignin, and suggested that the expression of transformation was confined to vessel walls.

• Molecules and Cells
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• v.46 no.8
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• pp.461-469
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• 2023

The tail of the striatum (TS) is located at the caudal end in the striatum. Recent studies have advanced our knowledge of the anatomy and function of the TS but also raised questions about the differences between rodent and primate TS. In this review, we compare the anatomy and function of the TS in rodent and primate brains. The primate TS is expanded more caudally during brain development in comparison with the rodent TS. Additionally, five sensory inputs from the cortex and thalamus converge in the rodent TS, but this convergence is not observed in the primate TS. The primate TS, including the caudate tail and putamen tail, primarily receives inputs from the visual areas, implying a specialized function in processing visual inputs for action generation. This anatomical difference leads to further discussion of cellular circuit models to comprehend how the primate brain processes a wider range of complex visual stimuli to produce habitual behavior as compared with the rodent brain. Examining these differences and considering possible neural models may provide better understanding of the anatomy and function of the primate TS.

• Clinics in Shoulder and Elbow
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• v.19 no.4
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• pp.216-222
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• 2016

Background: We investigated the effectiveness of fibular strut allograft augmentation of proximal humerus fractures to prevent varus deformity in patients over the age of 65 years with insufficient medial support. Methods: We analyzed the clinical and radiological outcomes of locking plate fixation with adjunct fibular strut allograft augmentation in 21 patients with proximal humeral fractures. The inclusion criteria were age (65-year-old or older); presence of severe medial comminution; inadequate medial support; and those who could participate in at least a one year follow-up. The average age was 76.4 years. We analyzed each patient's Constant score, our indicator of clinical outcome. As radiological parameters, we analyzed time-to-bone union; restoration of the medial hinge; difference between the immediately postoperative and the last follow-up humeral neck-shaft angles;; and anatomical reduction status, which was assessed using the Paavolainen method. Results: A successful bone union was achieved in all patients at an average of 11.4 weeks. We found that the average Constant score was 74.2, showing a satisfactory outcome. The average difference in the humeral neck-shaft angles between the immediately postoperative time-point and at the final follow-up was $3.09^{\circ}$. According to the Paavolainen method, the anatomical reduction was rated excellent. The medial hinge was restored in 14 of 21 patients. Although we did not find evidence for osteonecrosis, we found that a single patient had a postoperative complication of screw cut-out. Conclusions: Fibular strut allografting as an adjunct treatment of proximal humeral fractures may reduce varus deformity in patients with severe medial comminution.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.22
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• pp.9649-9654
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• 2014

Background: Polyps are common lesions in the gastrointestinal (GI) tract. Colon cancer is mostly a result of progression from polyps. The present study aimed to evaluate demographic, clinical, and histological characteristics of colorectal polyps in Iran, particularly neoplastic and advanced types. Materials and Methods: Over a period of 10 years, specimens of all colorectal polyps obtained from colonoscopy were studied. The variables subjected to statistical analysis were age, sex, and the chief clinical complaint of the patients who underwent colonoscopy, their motivation, and the site, size, and histological types of detected polyps. The level of significance was set at p value <0.05. Results: Data were obtained from a total of 352 patients. No difference was seen between male and female patients regarding histological types. Only in nine patients was screening the reason for colonoscopy. Almost two-thirds (66.2%) of the polyps were neoplastic. Familial polyposis syndrome and inflammatory bowel disease were seen in 4.3% and 3.0% of the patients with neoplastic polyps, respectively. Sites of polyps were the sigmoid, rectum, and descending colon in 40.1%, 34.5%, and 17% of the cases, respectively. The advanced type made up 58.8% of neoplastic polyps. Only 3.6% of the patients undergoing colonoscopy in the study period had biopsied polyps. Discussion: No difference was observed between male and female patients in terms of overall incidence of polyps, histological and anatomical profiles, and mean age distribution. Anatomical and histological profiles agreed with the studies performed in areas with a low risk of colon cancer. The findings show that colonoscopy was not performed when it was necessary. A meaningful increase in the number polyp biopsy cases and a corresponding decrease in polyp size in the last few years of the study can be associated with the presence of more GI specialist clinicians in hospital centers, and this holds out much hope for the further improvement of the situation in the future.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.6
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• pp.510-518
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• 2009

Purpose: In this study, we analyzed and compared the anatomical position of the mandibular canal in normal occlusion and mandibular prognathism patients. Patients and Methods: Computed tomography image from 58 patients were divided into normal occlusion group and mandibular prognathism group, and each measurement were taken in the each measuring points(2nd premolar, 1st molar, 2nd molar, 3rd molar, ramus). Measurements were statistically analyzed by student's t-test. Results: BC (Thickness of the buccal cortex) value was 2.3~2.7 mm, CB (Distance from the canal to the lingual aspect of the buccal cortex) value was 1.3~4.3 mm, MC (Diameter of the canal) value was 3.2~3.8 mm, LI (Distance from the canal to the lingual aspect of the lingual cortex) value was 2.0~3.7 mm, TM (Thickness of the total mandible) value was 9.5~12.9 mm and CM (Distance from the canal to the inferior border of the mandible) value was 6.9~17.5 mm. Conclusion: In the comparison between two groups, there was statistically significant difference in CB value of 2nd, 3rd molar between normal occlusion and mandibular prognathism, and other value in the rest of the measuring points didn't show statistically significant difference.