• Korean Journal of Poultry Science
• /
• v.40 no.2
• /
• pp.83-89
• /
• 2013

iNOS (Inducible nitric oxide synthase) and TLR-4 (Toll-like Receptor-4) play crucial roles in innate immunity of poultry. iNOS has been mapped to chicken chromosome 14 and implicated in a variety of chicken diseases. iNOS possesses potent antimicrobial activity, including the inhibition of microbes replication in vitro. TLR-4 is a pathogen associated molecular-pattern receptor for bacterial product, such as LPS (lipopolysaccharides) found in Gram negative bacteria, that triggers pro-inflammatory cytokine expression after engagement with ligands. In the previous studies, genetic analysis of iNOS and TLR-4 revealed the possible association of mutation in these genes with the intestinal microflora of cecum when infected with Salmonella spp. This study was aimed to augment previous findings, which show the association of iNOS (C14513T) and TLR-4 (G4409T) polymorphisms with economic traits in Korean Native Black (KNB), Rhode Island Red (RIR) and Cornish chickens. Investigation in the effect of SNPs on economic traits (layday, layw, layno, bw150, bw270, layw270) was conducted. iNOS (C14513T) had a significant effect on the average body weight at 270 days of age (p<0.05) in both KNB and RIR, whereas TLR-4 (G4409T) showed no significant correlation with all traits (p>0.05). The results obtained from using the candidate genes can be useful for the genetic improvement of body weight in both KNB and RIR breeds.

• Journal of Yeungnam Medical Science
• /
• v.14 no.2
• /
• pp.359-369
• /
• 1997

We studied the expression of the cell surface antigen associated with myeloid and lymphoid leukemias on bone marrow or peripheral blood blast cells from 153 leukemic patients including 61 cases of acute myelogenous leukemias(AML), 46 of acute lymphocytic leukemias(ALL) and 12 of acute leukemias. They were analyzed by direct or indirect immunofluorescence method for reactivity with the monoclonal antibodies to B cells(CD10, CD19, SmIg), T cells(CD2, CD5, CD7, CD3, CD4, CD8), myeloid antigen(CD13, CD14, CD33, CD61) and a nonspecific antigen, HLA-DR. Lymphoid associated markers detected on AML is CD7 32.8%, CD10 14.8%, CD5 13.1%, CD2 6.6% and CD19 1.6%. TdT was positive in 4.9% of AMLs. Hybrid leukemias were 8 cases out 61 AML cases and were mainly composed of monocytic lineage, M4 and M5a. Myeloid markers detected in ALL were CD13 2.2% and CD33 2.2%. In this study, immunologically classified ALLs were composed of 65.2% of CALLA (+) B precursor type, 10.9% of CALLA (-) B precursor pattern, 8.7% of T cell type, 2.2% of B cell type, 4.5% of mixed lymphoid lineage(B&T), 2.2% of undifferentiated leukemia, and 6.5% of hybrid leukemia. Twelve cases of acute leukemias ware finally diagnosed to be 5 cases of hybrid leukemia, 3 cases of B lineage, 3 case of T lineage and 1 case of mixed lymphoid(B&T) leukemia. In summary, we think the best method for typing acute leukemias is by using a combination of FAB classification and immunophenotying.

• The Journal of Art Theory & Practice
• /
• no.6
• /
• pp.77-99
• /
• 2008

The purpose of this study is to show that the reason behind the ambivalent characteristic displayed in Niki de Saint Phalle's works is in her trauma and how such characteristic can be extracted from her works. During her creative years, Saint Phalle worked on various materials from different genres such as assemblages, shooting paintings, a series on Bride and Monster, 'Nana', 'Tarot Garden'and public sculptures. One commonality found among her various works is the ambivalent characteristic that contains contrasting elements simultaneously. Saint Phalle suffered a terrible psychological damage inflicted by her parents during her childhood. Specifically, she was sexually assaulted by her father and emotionally neglected by her mother, the trauma that affected her for the rest of her life. As a result, she came to develop extreme love- hate relationships with her parents and this became the main reason for the ambivalent characteristic displayed in her works. The love-hate relationship Saint Phalle developed can be identified through various researches done on the subject of the affect of sexual assault. It is common for incest victims to develop ambivalent feelings towards the perpetrator and Saint Phalle was no exception. Dissociation disorder and a snake well explain the trauma from her father. It is a generally accepted belief in the field of psychology that dissociation disorder commonly occurs to children who experience incest. And dissociation disorder is similar to the characteristic of ambivalence in the sense that a single entity contains more than two contrasting elements at the same time. In addition, the amputated doll objects used in her assemblages coincide with the expression of body detachment of people with dissociation disorder. These facts clearly indicate that the trauma from her father is showing through in her works. A snake is a subject matter that reflects the ambivalent tendency of Saint Phalle that resulted from her trauma. She remembers her father's rape as an image of a snake which is related to a phallic symbol in mythology or art reflecting her trauma. Moreover, she displays a similar pattern of ambivalent emotion like love and hate or fear towards a snake and her father. This is also confirmed by her portrayal of a snake as a monster or reversely as a creature with fundamental vitality in her works. The lack of affection from her mother can be explained by her mother's maternal deprivation. It appears that Saint Phalle's mother possessed all the causes for maternal deprivation such as maternal separation, personality disorder and inappropriate attitude towards child rearing. Especially, a study that shows mother's negative attitude towards child breeding tends to increase dissociation experience of children is another important evidence that supports Saint Phalle's dissociation tendency. These traces of Saint Phalle's trauma are clearly revealed in her assemblages and shooting paintings. The violent objects in her assemblages such as a hammer, razor, nail represent the rage and defensiveness towards her father. The objects such as fragments of broken plates of feminine patterns, pots and mirrors that her mother used symbolize the affection towards her mother. On the other hand, the destructed objects can be interpreted as her hate and resentment towards her mother. Shooting paintings contain her extreme fury and hate. Things such as acts of shooting and the image associated with blood after shooting are blunt expressions of her bursts of emotions. I have tried to define and classify the ambivalent characteristics shown in her assemblages and shooting paintings as hate, rage, violence, calm, love and pleasure according to the frame of Thanatos and Eros. Out of the six, hate, rage, violence and clam are associated with Thanatos while love and pleasure are associated with Eros and they correspondingly form an ambivalent structure. These ambivalent characteristics can be found in her assemblages and shooting paintings. The objects in her assemblages such as a razor, saw, hammer imply hate, rage, violence and the silence felt throughout her works represent calmness. And, as mentioned, the feminine objects can be seen as symbolizing love. In shooting paintings, hate, rage, violence can be found in the use of force and in the traces of watercolor after shooting, and a sense of pleasure in her feelings of catharsis after her shooting. Moreover, a shielded calmness can be found on the plywood all covered with plaster before the shooting. This study looked into the ambivalent characteristic of Saint Phalle's works by examining her trauma to find its correlation, and a meaning of this study can be found from the fact that it refocused the origin of Saint Phalle who is generally known as a feminist artist. Additionally, a meaning of the study can be found also from the fact that it examined the ambivalent characteristics of her works through a frame of Thanatos and Eros.

• Radiation Oncology Journal
• /
• v.21 no.4
• /
• pp.306-314
• /
• 2003

Purpose : In our Previous study, we have shown the main cel1 death pattern Induced by irradiation or protein tyrosine kinase (PTK) inhibitors in K562 human myeiogenous leukemic cell line. Death of the cells treated with irradiation alone was characterized by mitotic catastrophe and typical radiation-induced apoptosis was accelerated by herblmycin A (HMA). Both types of cell death were inhibited by genistein. In this study, we investigated the effects of HMA and genistein on cell cycle regulation and its correlation with the alterations of radiation-induced cell death. Materials and Methods: K562 cells In exponential growth phase were used for this study. The cells were Irradiated with 10 Gy using 6 MeV Linac (200-300 cGy/min). Immediately after irradiation, cells were treated with 250 nM of HMA or 25 $\mu$N of genistein. The distributions of cell cycle, the expressions of cell cycle-related protein, the activities of cyclin-dependent kinase, and the yield of senescence and differentiation were analyzed. Results: X-irradiated cells were arrested In the G2 phase of the cell cycle but unlike the p53-positive cells, they were not able to sustain the cell cycle arrest. An accumulation of cells in G2 phase of first ceil-cycle post-treatment and an increase of cyclin Bl were correlated with spontaneous, premature, chromosome condensation and mitotic catastrophe. HMA induced rapid G2 checkpoint abrogation and concomitant p53-independent Gl accumulation. HMA-induced cell cycle modifications correlated with the increase of CDK2 kinase activity, the decrease of the expressions of cyclins I and A and of CDK2 kinase activity, and the enhancement of radiation-induced apoptosis. Genistein maintained cells that were arrested in the G2-phase, decreased the expressions of cyclin Bl and cdc25c and cdc25C kinase activity, increased the expression of pl6, and sustained senescence and megakaryocytic differentiation. Conclusion: The effects of HMA and genistein on the radiation-induced cell death of KS62 cells were closely related to the cell cycle regulatory activities. In this study, we present a unique and reproducible model in which for investigating the mechanisms of various, radiation-induced, cancer cell death patterns. Further evaluation by using this model will provide a potent target for a new strategy of radiotherapy.

• Journal of Korean Academy of Nursing
• /
• v.20 no.3
• /
• pp.430-458
• /
• 1990

Care is a central concept of nursing. Nursing would not exist without caring. Care and quality of life are closely related. Human behavior is a manifestation of culture. We can say that caring and nursing care are expression of culture. The nurse must understand the relationship of culture with care for ensure quality nursing care. But knowledge of cultural factors in nursing is not well developed. Time and in - depth study are needed to find meaningful relationships between culture and care. Nurses recognized the importance of culturally appropriate nursing There are two care systems in culturally based nursing. The folk care system and the professional nursing care system. The folk care system existed long before the professional nursing care system was introduced into this culture. If the discrepancy between these two care systems is great, the client may receive inappropriate nursing care. Culture and subcaltures are diverse and dynamic in nature. Nurses need to know the caring behaviors, patterns, and their meaning in their own culture. In Korea we have taken some first step to study cultural nursing phenomena. It is not our intent necessarily to return to the past and develop a nationalistic of nursing, but to identify the core of traditional caring and relate that to professional nursing care. Our Assumptions are as follows : 1) Care is essential for human growth, well being and survial. 2) 7here are diverse and universal forma, expressions, patterns, and processes of human care that exist transcul - turally. 3) The behaviors and functions of caring differ according to the social structure of each culture. 4) Cultures have folk and professional care values, beliefs, and practices. To promote the quality of nursing care we must understand the folk care value, beliefs, and practices. We undertook this study to understand caring in our traditional culture. The Goals of this study were as follows : 1) To identify patterns in caring behavior, 2) To identify the structural components of caring, and 3) To understand the meaning and some principles of caring. We faised several questions in this study. Who is the care-giver? Who is the care-receipient? Was the woman the major care -giver at any time? What are the patterns in caring behavior? What art the priciples underlying the caring process? We used an interdisciplinary team approach, composed of representatives from nursing and anthropology, to contribute in -depth understanding of caring through a socicaltural perspeetive. A Field study was conducted in Ro-Bong, a small agricultural kinship village. The subjects were nine women and one man aged be or more years of age. Data were collected from january 15 to 21, 1990 through opem-ended in-depth interviews and observations. The interview focused on caring behaviors sorrounding birth, aging, death and child rearing. We analysed these data for meaning, pattern and priciples of caring. In this report we describe caring behaviors surrounding childbirth. The care-givers were primarily mothers- in -low, other women in the family older than the mother - to- be, older neighbor woman, husbands, and mothers of the mother-to- be. The care receivers were the mother-to-be the baby, and the immediate family as a component of kinship. Emerging caring behavior included praying, helping proscribing, giving moral advice(Deug - Dam), showing concern, instructing, protecting, making preparations, showing consideration, touching, trusting, encouraging, giving emotional comfort, being with, worrying about, being patient, preventing problems, showing by an example, looking after bringing up, taking care of postnatal health, streng thening the health condition, entering into another's feelings(empathizing), and sharing food, joy and sorrow The emerging caring component were affection, touching, nurtuing, teaching, praying, comforting, encouraging, sharing. empathizing, self - discipline, protecting, preparing, helping and compassion. Emerging principles of. caring were solidarity, heir- archzeal relationships, sex - role distinction. Caring during birth expresses the valve of life and reflects the valued traditional beliefs that human birth is given by god and a unique unifying family event reaching back to include the ancestors and foreward to later generations. In addition, We found positive and rational foundations for traditionl caring behaviors surrounding birth, these should not be stigmatized as inational or superstitious. The nurse appropriately adopts the rational and positive nature of traditional caring behaviors to promote the quality of nursing care.

• Journal of the Korean Society of Costume
• /
• v.36
• /
• pp.183-203
• /
• 1998

The wave of Avant-garde swept away all in the unique social background so called 'October Revolution' and the early 1900 Russian society which was able to absorb and accept anything. The Russian avant-garde has been affected by the Cubism and the Futurism those had peculiarly appeared in the early twentieth century, spreaded out to three spheres: the Suprematism, the Rayonism and the Constructivism. The Russian Constructivism has appeared in this background, concretely and ideally ex-pressed the ideology of the revolution into the artistic form and made an huge influence to the whole Russian society. The Constructivist like Tatlin, naum Gabo, Pevaner, Rodchenko, Stepanova, Popova and Exter gave great effect on the Soviet Constructive fashion design in 1920's after the Revolution. The Soviet costume in 1920s hold in common the characteristicss of the Constructive graphic as it is, geometrical and abstractive form, energetic and motility. In fashion design, these graphic qualities have been showed as the application of geometrical form and architectural image, physical distortion and transformation. And in textile design, the simple, dynamical presentation has been appeared. We can classify the Soviet costume at this time into three occasions. The first term is from late 1910 th mid 1920, and it is altered from folk costume design to modern one. With Lamanova as the first on the list, using the folk mitif, the Constructive expression of simple form has been gradually revealed in design. Designers like Makarova, Pribylskaia and Mukhina produced the plane, simple chemise style with the decoration of the Russian traditional motif. From early to late 1920 is the second term, and it is at the pick of the most active processing of the Constructive design. Not only at the costume in daily life but also at the theatrical costume and textile, the con-structive design has been represented all avail-able fields. Many Constructivists including Stepanova, Popova, Exter and Rodchenko took part in the textile design and costume design so as to evlvo their aesthetic concept. The third term is from late 1920 to early 1930. The socialistic realism has dominated over the whole culture and art, the revolutionary dynamic motif has been presented also in textile design. The formative features of Soviet Constructive fashion design are; silhouette, from, motif, color and fabric. The first, the silhouette : a straight rectangular silhouetted has been expressed through the whole period and a volumed one with distorted human body shape has introduced in the theatrical costume design. The second, the form: many lengthened rectangular forms have been made at beginnings, but to the middle period, geometrical, architectural forms have been more showed and there are energy and movement in design. At the last period, only a partial feature-division has been seen. The third, the motif; no pattern or ethnic motif has been partly used at beginnings, a figure like circle, tri-angle has gradually appeared in textile design. At latter period, a real-existent motif like an airplane has been represented with graphing and simplicity. The fourth, the color ; because of insufficient dyeing, neutral color like black or grey color has been mainly covered, but after middle term, a primary color or pastel tone has been seen, contrast of the fabric; without much development of textile industry after the Revolution, thick and durable fabrics have been the main stream, but as time had going to the last period, fabrics such as linen, cotton, velvet and silk have been varously choesn. At the theatrical costume, new materials like plastics and metals that were able to accentuate the form. The pursuit of popularity, simplicity and functionalism that the basic concept of Constructive fashion is one of the "beauty" which has been searching in modern fashion. And now we can appreciate how innovative and epochal this Soviet Constructive fashion movement was.ement was.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
• /
• v.6 no.1
• /
• pp.81-97
• /
• 2000

Objectives: This experimental study was carried out to evaluate the effects of aqueous and methanol extracts of Hedyotis diffusa which has long been used for cancer treatment in oriental medicines on the induction of apoptotic cell death in human lymphoid leukemia cell line, HL-60. Methods: Cells were treated with various concentrations (200 to $0.4{\mu}g$) and periods (6 to 30 hr) of $H_2O$ and methanol extracts of Hedyotis diffusa. Then, cells were tested for viability by MTT assay. Cells wrere treated with $200{\mu}g/ml$ of methanol extract fork various periods. Genomic DNA was isolated, separated, on 1.5% agarose gels, stained with ethidium bromide and visualized under UV light. Cells were treated with $200{\mu}g/ml$ of each extract for 16 hr. Then, cells were treated with Hoechst dye 33342 and observed by fluorescence microscopy. Cells were treated with various doses of each for 12 hr and $100{\mu}g/ml$ of methanol extract for various periods. Lysate from the cells used to measure the activity of Caspase-1 and-3 proteases by using fluorogenic peptide substrates including acetyl-YVAD-AMC and acetyl-DEVD-AMC, respectively. Cells were treated with $200{\mu}g/ml$ of each extract for various periods. Cell lysates were immunoprecipated with anti-JNKl antibodies. The immune complex was reacted with $32^p-ATP$ and c-Jun as a substrate. The phosphotransferase activity of JNKI was measured by using PhosphoImage analyzer (Fuji Co., Japan). Nuclear extracts were isolated and incubated with oligonucleotide probe of $NF-{\kappa}B$. Transcriptional activation of ${\kappa}B$ was measured by using EMSA and visualized by PhosphoImage analyzer (Fuji Co, Japan). Cell lysates were prepared and analyzed by Western blotting with anti-Bc12 antibodies and anti-Bax antibodies. Cells were pretreated with various doses of methanol extract for 2 hr. Then, the extract was removed by centrifugation. Cells were resuspended with RPMI-1640 media containing 0.3% agarose, 10% FBS, overlayred onto bottom layer agarose and incubated at $CO_2$ incubator for 6 days. The number of colony was counted under light microscopy ($\time100$). Results: The death of HL-60 cells was markedly induced by the addition of methanol extract of Hedyotis diffusa in a dose and time-dependent manners. The apoptotic characteristic ladder pattern of DNA strand break was observed in death of HL-60 cells. In addition, it was shown nucleus chromatin condensation and fragmentation under Hoechst staining. Therefore, Hedyotis diffusa extract-induced death of HL-60 cells is mediated by apoptotic signaling processes. The activity of Caspase 3-like proteases remained in a basal level in HL-60 cells treated with aqueous extract of Hedyotis diffusa. However, it was markedly increased in HL-60 cells treated with methanol extract of Hedyotis diffusa. In addition, the phosphotransferase activity of JNKl was increased in HL-60 cells treated with methanol extract of Hedyotis diffusa. Furthermore, the activation of transcriptional activator, $NF-{\kappa}B$ was markedly induced by methanol extract of Hedyotis diffusa. Anti-apoptotic Bc12 was cleaved into 23Kda fragment by treatment of methanol extract of Hedyotis diffusa. However, expression of proapoptotic Bax protein was increased by treatment of methanol extract of Hedyotis diffusa in a time-dependent manner. Furthermore, methanol extract markedly inhibited the colony forming efficiency of HL-60 cells in semisolid agar culture. Conclusions: Above results suggest that methanol extract of Hedyotis diffusa induces the apoptotic death of human leukemic HL-60 cells via activations of Caspase-3 proteases, JNKI, transcriptional activator $NF-{\kappa}B$, In addition, our results also suggest that methanol extract of Hedyotis diffusa reduces the malignant potential of HL-60 cells via down regulation of colony forming effciency through cleavage of Bc12 as well as induction of Bax.

• Research in Plant Disease
• /
• v.12 no.3
• /
• pp.213-220
• /
• 2006

In year 2003, a soybean(Glycine max) sample showing severe dwarfing symptom was collected from a farmers' field in Cheongsong in Korea. The results from the diagnosis of the sample by RT-PCR revealed that it was infected by Soybean dwarf virus(SbDV), SbDV-L81. This study could be the first report of the occurrence of the virus in Korea. To further characterize the virus, the partial nucleotide sequence of the genomic RNA of SbDV-L81 was determined by RT-PCR using species-specific primers. The sequences were analyzed and subsequently compared to previously characterized strains of SbDV based on the pattern of symptom expression and vector specificities. The intergenic region between ORF 2 and 3 and the coding regions of ORF 2, 3 and 4 were relatively similar to those of dwarfing strains(SbDV-DS and DP) rather than those of yellowing strains(SbDV-YS and YP). Likewise, the result from the analysis of 5'-half of the coding region of ORF5 indicated that SbDV-L81 was closely related to strains(SbDV-YP and DP) transmitted by Acyrthosiphon pisum. These data from the natural symptom and the comparisons of five regions of nucleotide sequences of SbDV suggested that SbDV-L81 might be closely related SbDV-DP.

• Korean Journal of Heritage: History & Science
• /
• v.53 no.3
• /
• pp.62-79
• /
• 2020

The rock-carved seated Avalokiteśvara statue at Ganghwa Bomunsa Temple is a giant rock-carved Buddhist statue that was built in 1928 during the Japanese colonial era. Although it is a year-recorded Buddhist statue that occupies a prominent place in modern Korean Buddhist sculpture history, it has not been the subject of in-depth discussion due to weak research on modern Buddhist sculptures. In this study, to examine the various significant aspects of the rock-carved Seated Avalokiteśvara statue at Bomunsa Temple as a modern Buddhist sculpture, I have managed to determine its construction year, artificers, and patrons by deciphering the inscription around the rock-carved statue; in addition I have researched the effects of the rock shapes and landforms on the formation of the Buddhist statue by comparing and analyzing the points of view of both artificers and worshipers. I have also identified the specific circumstances of the time of construction from interviews with the descendants of artificers. A monk from Geumgangsan Mountain, Lee Hwaeung, took the role of sponsor and chief painter to construct the rock-carved seated Avalokiteśvara statue at Bomunsa temple. In the beginning of its construction in 1928, more than 100 donators jointly sponsored the construction of the statue. Gansong Jeon Hyoungphil sponsored alone at the time of the place of worship's expansion in 1938. Bomunsa Temple has been regarded as one of the top-three sacred places of Avalokiteśvara Bodhisattva together with Naksansa Temple in Yang Yang and Boriam in Nam Hae, due to the construction of the rock-carved statue. It took about three months to construct the statue. Lee Hwaeung drew a rough sketch and then Un Songhag and five masons from Ganghwa Island took part in the carving process. We can observe the line drawing technique around the rock-carved statue because the statue was carved based on the rough sketch of the monk painter. The aspect of Lee Hwaeung as a painter is revealed; therefore, we can identify the clue of painting pattern leading to Seogongchulyou- Hwaunghyoungjin- Ilonghyegag. The rock-carved seated Avalokiteśvara statue at Bomunsa Temple is a typical Avalokiteśvara that wears a jeweled crown and holds Kundica. It makes a strong impression as it has a big square-shaped face and a short neck and is unsophisticated in general. The artificers solved the issue of visual distortion of the rock-carved statue caused by carving on a 10-meter high and 40-degree sloping rock by controlling motion to its maximum, omitting detailed expression by emphasizing symmetry, and adjusting the head-to-body proportion to be almost one-to-one. In this study, especially, I presume the unified form of sacred sculptures and Buddhist altars, without making a Buddhist altar like the rock-carved seated Avalokiteśvara statue at Bomunsa Temple, to be a key characteristic of modern Buddhist sculptures. Furthermore, I make newly clear that the six letters of Sanskrit carved on nimbus, which had been interpreted as a Six-Syllable Mantra, are a combination with Jeongbeopgye and Sabang Mantras. In addition, three iron rings driven on eaves rock were used as a reference point, and after construction they were used as a decoration for the Bodhisattva with hanging wind chimes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.27 no.5
• /
• pp.404-416
• /
• 2001

Purpose : Traditionally, the treatement of choice has been a bone grafting procedure to increase the length of bone in case of actual length discrepancy. But, bone grafting procedure has many disadvantages, for example, graft resorption, donor site morbidity, and so on. So, many trials have been performed to avert the use of autogenous bone graft via introducing new materials or methods. And, one of those trials has been realized by the development of a technique inducing bone lengthening by osteotomy (or corticotomy) and slow gradual distraction of the osteotomized segments. This new technique of bone lengthening dates back to the early 20th century. But, the majority of information concerning the biology of new bone formation during bone lengthening and technical details of the procedure were produced by extensive clinical and experimental studies performed by Ilizarov, a Russian surgeon. According to Ilizarov, with adequate blood supply, preservation of periosteum, rigid fixation of the osteotomized segments, and proper rate and rhythm of distraction, intramembranous bone rapidly develops within the distraction gap in the limb lengthening procedure. In the limb lengthening, many orthopedic surgeons try to observe the biologic and clinical principles recommended by Ilizarov. In the oral and maxillofacial region, however, not a few studies must be performed to apply this surgical technique in the clinical cases. Besides, the mechanism of bone formation in the distraction gap is not clear, yet. The purpose of this experiment was to scrutinize serially the histological changes in the elongated bone affected by osteodistraction of the mandibular body in an adult canine model. In addition, it was performed to confirm the presence of specific region(s) which was important in the bone formation in the gap through the observation of the expression pattern of osteocalcin and osteonectin with the immunohistochemical examination. Materials and Methods : The experimental and control specimens were obtained from seven adult male mongrel dogs weighing over 20kg. The distractors were custom-made linear extraoral devices and bicortical fixation screws were 2.3mm in diameter, 50mm in total length, 15mm in screw length. The distractors were devised to produce a linear gap of 0.75mm between two bony segments every $360^{\circ}$ turn of the rotation rod of the device. The mandibular body of the right side of each animal was corticotomized perpendicular to the occlusal plane and then two bony segments were separated completely by careful manipulation of the segments with bone forceps. The left side of each animal was left intact. This side was served as control. At sixth day after osteotomy and fixation of the segments were performed, distraction of the segments was commenced with a rate of 1.1mm/day and a rhythm of two/day for ensuing 7 days. The animals were euthanized at the 16th. 29th, and 44th day after the osteotomy. The bony specimens were decalcified, embedded in paraffin, sectioned $5{\mu}m$ thick and stained with H&E. The prepared specimens were examined under the light microscope. And, immunohistochemical examinations using anti-osteocalcin antibody (OC1, Biodesign, USA) and anti-osteonectin antibody (Haematologic Technologies Inc., Essex, VT) to locate the expressions of osteocalcin and osteonectin, respectively, were performed. Results : 1. New bone was observed already at the 16th. day after osteotomy. This suggests that new bone formation in osteodistraction was commenced at an early stage of the regenerative process. But, radiologically and microscopically, bony union was not completed in the distraction gap at the 44th. day after osteotomy. Therefore, rigid fixation must be maintained between the bony fragments till the complete bony union is confirmed clinically rather than one month or so after the completion of distraction.