• Archives of Plastic Surgery
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• v.32 no.6
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• pp.744-752
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• 2005

Many craniofacial and neurosurgical procedures rely on cranial bone as a bone graft. In the majority of instances, the bone heals and gives good results. But we found that if either the dura or the pericranium were missing adjacent to the cranial bone, bone absorption would be increased. We studied a single animal model, investigating the contribution of the dura and the pericranium in the process of cranial bone absorption. The animals were divided into four groups of each five animals depending on the differential blockade of the dura and/or the pericranium by silastic sheet. Bilateral $100-mm^2$, parietal bone flaps were harvested from mature rabbits. Animals were humanely killed after 12 weeks, and histomorphometric analysis was performed. The volume maintenance is as follows; Group I; 89.0%, Group II; 80.0%, Group III; 63.3%, Group IV; 52.4%. The weight maintenance; Group I; 87.1%, Group II; 79.4%, Group III; 61.6%, Group IV; 51.1%. The histological contribution of living bone; Group I; 92.9%, Group II; 85.6%, Group III; 71.1%, Group IV; 56.2%. Significantly increased bone absorption occurred in Group II, III, IV compared with Group I. Conclusions are: 1. Cranial bone absorption is effected by both the dura and the pericranium. 2. The dura is more important than the pericranium in preventing cranial bone absorption. 3. The dura to be the source of central cranial bone and the pericranium to be the source of peripheral cranial bone.

• Journal of Biosystems Engineering
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• v.40 no.1
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• pp.78-88
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• 2015

Purpose: The objective of this study is to review researches regarding factors that potentially affect adolescent calcium (Ca) metabolism, and to suggest a potential modeling approach for optimizing gastrointestinal Ca absorption and peak bone mass. Background: Optimal gastrointestinal Ca absorption is a key to maximizing peak bone mass in adolescents. Urine Ca excretion in adolescents rises only after bone accretion is saturated, indicating that higher intestinal Ca absorption and bone retention is necessary to ensure maximum bone accretion. Hence, maximizing peak bone mass is possible by controlling the factors influencing gastrointestinal Ca absorption and bone accretion. However, a mechanism that explains the unique adolescent Ca metabolism has not yet been elucidated. Review: Dietary factors that enhance gastrointestinal Ca absorption may increase the available Ca pool usable for bone accretion, and a specific hormone may direct optimal Ca utilization to maximize peak bone mass. IGF-1 is an endocrine hormone whose levels peak during adolescence and increase fractional Ca absorption and bone Ca accretion. Prebiotics, generally obtained from dietary sources, have been reported to exert a beneficial effect on Ca absorption via microbiota activity. We selected and reviewed three candidates that could be used to propose a comprehensive Ca metabolic model for optimal Ca absorption and peak bone mass in adolescents. Modeling: Modeling has been used to investigate Ca metabolism and its regulators. Herein, we reviewed previous Ca modeling studies. Based on this review, we proposed a method for developing a comprehensive model that includes regulatory effectors of IGF-1 and prebiotics.

• The Korean Journal of Nuclear Medicine Technology
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• v.27 no.1
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• pp.4-6
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• 2023

Technetium-labeled phosphate bone scan was shown to detect bone fractures and bone metastasis in early stage than general radiographs. Therefore, bone scan has become one of the most frequently performed nuclear medicine imaging examination. However, non-osseous radiopharmaceutical uptake on the bone scan are unusual findings. We report a case of diffuse splenic absorption of Tc-99m dicarboxypropane diphosphonate in patients who undergo liver transplantation.

• Korean Journal of Exercise Nutrition
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• v.24 no.4
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• pp.24-27
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• 2020

[Purpose] Dehydroepiandrosterone (DHEA) administration reportedly recovers osteoporosis, a bone disorder associated with bone deficiency in postmenopausal women. However, the physiological mechanism of DHEA in osteoporosis remains elusive, especially in terms of intestinal calcium absorption. Therefore, we investigated the effect of DHEA administration on calcium absorption in ovariectomized (OVX) female rats using an estrogen receptor antagonist. [Methods] Female Sprague-Dawley rats (n=23, 6 weeks old) were randomized into three groups: OVX control group (OC, n=7), OVX with DHEA treatment group (OD, n=8), and OVX with DHEA inhibitor group (ODI, n=8) for 8 weeks. [Results] Intestinal calcium accumulation, as well as the rate of absorption, demonstrated no significant differences during the experimental period among investigated groups. The bone mineral density (BMD) of the tibia at the proximal metaphysis was higher in the OD group than that in the OC group (p<0.05); however, BMD of the ODI group showed no significant difference from investigated groups. Furthermore, the BMD of the tibia at the diaphysis did not significantly differ among these groups. [Conclusion] We revealed that DHEA administration does not involve intestinal Ca absorption, although this treatment improves BMD levels in OVX rats. These observations indicate that the effect of DHEA on the bone in postmenopausal women is solely due to its influence on bone metabolism and not intestinal calcium absorption.

• The Journal of Korean Physical Therapy
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• v.14 no.4
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• pp.412-422
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• 2002

The use of biochemical markers of bone turnover may be particular interest in the investigation of bone disorders with osteoporosis. Serum osteocalcin(OC), total alkaline phosphatase and procollagen C, reflecting bone formation, and urinary pyridinium cross-links excretion, reflecting bone reabsorption have been measured in hyperthyroidism, postmenopause women, after testosterone supplementation, androgen, testosterone and estrogen deficiency, bone mineral density degree, age duration. Bone marks which is reflect to metabolic bone disorders are biochemical indices method to measure enzyme activity about bone formation, bone absorption and bone components in blood or urine. Bone metabolism biochemical marks are correlated with osteophorotic agents and also represent significantly different between bone mineral density and bone biochemical marks. Therefore if we develope and use bone metabolism marks which have higher sensitivity and specificity in bone formation and bone absorption, I think that these bone biochemical marks can have utility in the clinical application to predict osteoporosis risk group, bone loss, bone fracture and response degree to treatment of osteoporosis risk groups.

• The Journal of Korean Academy of Prosthodontics
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• v.30 no.4
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• pp.582-610
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• 1992

The long-term success of any dental implant is dependent upon the optimization of stresses which occur during oral function and parafunction. Especially, it has been suggested that there is an unique set of problems associated with joining an osseointegrated implant and a natural tooth with a fixed partial denture. For this particular case, although many literatures suggest different ways to avoid high stress concentrations on the bone surrounding the implant under static and dynamic loading conditions, but few studies on the biomechanical efficacy of each assertion have been reported. The purpose of this investigation was to evaluate the efficacies of clinically suggested methods on stress distribution under static load and shock absorption under dynamic load, using two dimensional finite element method. In FEM models of osseointegrated implant-natural tooth supported fixed partial dentures, calculations were made on the stresses in surrounding bone and on the deflections of abutments and superstructure, first, to compare the difference in stress distribution effects under static load by the flexure of fastening screw or prosthesis, or intramobile connector, and second, to compare the difference in the shock absorption effects under dynamic load by intramobile connector or occlusal veneering with composite resin. The results of this analysis suggest that : 1. Under static load condition, using an implant design with fastenign screw connecting implant abutment and prosthesis or increasing the flexibility of fastening screw, or increasing the flexibility of prosthesis led to the .increase in height of peak stresses in cortical bone surrounding the implant, and has little effect on stress change in bone around the natural tooth. 2. Under static load condition, intramobile connector caused the substantial decrease in stress concentration in cortical bone surrounding the implant and the slight increase in stress in bone around the natural tooth. 3. Under dynamic load condition, both intramobile connector and composite resin veneering showed shock absorption effect on bone surrounding the implant and composite resin veneering had a greater shock absorption effect than intramobile connector.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.2
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• pp.74-79
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• 2003

The functional properties such as a firming maintenance capacity for fermented vegetables, protein coagulation capacity antibacterial activity, calcium and peroxide absorption capacity of calcium powder of cuttle bone treated with acetic acid (ATC) were examined. In the Korean pickled cucumbers (20 days), the calcium content of ethanol insoluble solids was 5,264.9 mg/100 g and this value was higher than that of control (2,036.4 mg/100 g). Protein coagulation capacity of ATC was $0.9\%$ and its calcium absorption capacity was $49.3\%.$ The peroxide absorption capacity of ATC was shown $0-1.1\%$ range. Antibacterial activity was detected above $0.2\%.$ The ATC was effective in a firming maintenance of fermented vegetables (cucumber), coagulation capacities for soybean milk and antibacterial activity. The ATC was not effective in clarifying wastewater. Peroxide absorption capacity toward linoleic acid could not be checked by ATC, but its calcium absorption ratio was high compared to that of commercial calcium powder.

• The Journal of Internal Korean Medicine
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• v.22 no.2
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• pp.175-181
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• 2001

Objectives : This study was undertaken to study the action mechanism of Rhizoma Davalliae (RD) at parameter related to regulating bone density. Methods : We measured alkaline phosphatase activity and the contents : calcium, hydroxyproline, osteocalcin, calcitonin, and parathyroid hormone after the ovariectomized rats had been treated with RD for 30 days. Results : The following changes occurred: First, the serum calcium content and the calcitonin content, which decreased in ovariectomized rats, increased with RD treatment. Second, the serum alkaline phosphatase activity, the parathyroid hormone ativity, the osteocalcin content, the urinary calcium content, and the hydroxyprolin content-which increased in ovariectomized rats-decreased with RD treatment. Conclusions : These results show that RD treatment can recover abnormal calcium metabolic process by sex hormone inequality, promoting bone formation and inhibiting bone absorption.

• Nutritional Sciences
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• v.7 no.3
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• pp.151-157
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• 2004

The aim of this study was to investigate the effects of chicory fructan fiber supplementation on bone mineral density, apparent absorption of minerals and serum parameters related to bone turnover in postmenopausal women. Twenty-six healthy Korean postmenopausal women participated in the study. 1be participants were randomly divided into two groups in a double-blind parallel design and took one of the supplements for 3 months; either a placebo of 8g maltodextrins/sucrose mixture (control group) or 8g chicory fructan fiber (fructan group). During the 3-month experimental period no differences were found in bone mineral density (BMD) between the two groups. Apparent calcium absorption significantly increased by 42% in the fructan group, while that of the control group decreased by 29% as compared to the values at baseline. Urinary calcium excretion was not significantly different between the group;;. After 3 months, the level of serum alkaline phosphatase (ALP) was significantly lower in the fructan group than in the control group and deoxypyridinolin showed a trend toward a slight reduction. In conclusion, intake of chicory fructan fiber with a regular increases apparent calcium absorption in postmenopausal women.

• Journal of Veterinary Clinics
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• v.20 no.1
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• pp.91-95
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• 2003

It has been known that periods of absorption varies allografts or xenografts of transplantations of freeze-dried cortical bone(FDCB). In this study changes of absorption of FDCB in xenograft transplantations were evaluated according to extracted time with chloroform-methanol solution(CM sol.). The FDCB from pig was removed soft tissue by surgical knife. Fat of the FDCB was removed with treatments of CM sol. for 2, 6, and 10 days, then the treated FDCB was freeze-dried at $-80^{\circ}C$ and sterilized with ethylene oxide gas. The FDCB was transplanted to fifteen millimeter artificial-defected regions of 6 dogs on fibular diaphyses. This was biweekly examined by radiograph for 18 weeks. In result new bone formation with FDCB treated for 6 days was higher than the other bones treated for 2 and 10 days. Duration of absorption with FDCB treated for 6 days was longer than the others. The remain with FDCB treated for 10 days was more than the others.