• Restorative Dentistry and Endodontics
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• v.24 no.1
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• pp.166-179
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• 1999

Apical sealing is essential for the success of surgical endodontic treatment. Root-end cavity is apt to be contaminated with moisture or blood, and is not always easy to be dried completely. The purpose of this study was to evaluate the influence of dry methods of retrocavity on the apical seal in endodontic surgery. Apical seal was investigated through the evaluation of apical leakage and adaptation of filling material over the cavity wall. To investigate the influence of various dry methods on the apical leakage, 125 palatal roots of extracted human maxillary molar teeth were used. The clinical crown of each tooth was removed at 10 mm from the root apex using a slow-speed diamond saw and water spray. Root canals of the all the specimens were prepared with step-back technique and filled with gutta-percha by lateral condensation method. After removing of the coronal 2 mm of filling material, the access cavities were closed with Cavit$^{(R)}$. Two coats of nail polish were applied to the external surface of each root. Apical three millimeters of each root was resected perpendicular to the long axis of the root with a diamond saw. Class I retrograde cavities were prepared with ultrasonic instruments. Retrocavities were washed with physiologic saline solution and dried with various methods or contaminated with human blood. Retrocavities were filled either with IRM, Super EBA or composite resin. All the specimens were immersed in 2% methylene blue solution for 7 days in an incubator at $37^{\circ}C$. The teeth were dissolved in 14 ml of 35% nitric acid solution and the dye present within the root canal system was returned to solution. The leakage of dye was quantitatively measured via spectrophotometric method. The obtained data were analysed statistically using one-way ANOVA and Duncan's Multiple Range Test. To evaluate the influence of various dry methods on the adaptation of filling material over the cavity wall, 12 palatal roots of extracted human maxillary molar teeth were used. After all the roots were prepared and filled, and retrograde cavities were made and filled as above, roots were sectioned longitudinally. Filling-dentin interface of cut surfaces were examined by scanning electron microscope. The results were as follows: 1. Cavities dried with paper point or compressed air showed less leakage than those dried with cotton pellet in Super EBA filled cavity (p<0.05). However, there was no difference between paper point- and compressed air-dried cavities. 2. When cavities were dried with compressed air, dentin-bonded composite resin-filled cavities showed less apical leakage than IRM- or Super EBA-filled ones (p<0.05). 3. Regardless of the filling material, cavities contaminated with human blood showed significantly more apical leakage than those dried with compressed air after saline irrigation (p<0.05). 4. Outer half of the cavity showed larger dentin-filling interface gap than inner half did when cavities were filled with IRM or Super EBA. 5. In all the filling material groups, cavities contaminated with blood or dried with cotton pellets only showed larger defects at the base of the cavity than ones dried with paper points or compressed air.

• Journal of agricultural medicine and community health
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• v.29 no.1
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• pp.43-63
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• 2004

Objectives: The purpose of this study was to classify the patterns of health behaviors of some rural residents in Korea by sub-grouping them into populations with similar patterns of diet quality, physical activity, alcohol consumption and cigarette smoking, and then to investigate the relationship between these health behavior patterns and health status or health management of them. Methods: The study subjects were 722 rural residents above 20 years old on a typical rural district in Korea, and the data used in this study was from the survey data for health planning of a health center. Study questionnaire for this survey was developed from modifying the questionnaire for 'National Nutrition and Health Study' conducted in 1998. To classify health behavior patterns, cluster analysis was conducted. And to test the association of health behavior patterns with health status or health management, multiple logistic regression analysis were conducted. Results: The results and their implications of this study were as follows: 1. We identified six health behavior typologies : 67.8% of the sample had a good diet quality but showed sedentary activity level(good diet lifestyle) and 10.9% had heavy smoking behavior(smoking lifestyle). Individuals included in fitness lifestyle cluster(6.2%) had high physical activity level and those in drinking life style(2.6%) had had mainly large amount of alcohol. Zero point six percent of sample were included in hedonic lifestyle cluster, who showed poor health behaviors in all. Those included in passive lifestyle(11.9%) had no active health promoting activities but tended to avoid risk taking health behavior such as cigarette smoking and alcohol drinking. 2. As a result of logistic regression analysis, to compare with the individuals in good diet lifestyle, the prevalence of chronic diseases of those in fitness lifestyle showed higher and that of those in smoking lifestyle, drinking lifestyle, hedonic lifestyle, passive lifestyle showed lower than them, retrospectively. 3. Adjusting with general characteristics and health status, to compare with the individuals in good diet lifestyle, the proportion of those who had good health management practices in fitness lifestyle was higher, and the proportion of those who had health check in past 2 years was lower than them, retrospectively. Conclusions: There were some differences in health behavior patterns between rural population and national population, which influenced significantly on health status and health management practice of them. We suggested that the health promotion program for them be developed with considering these points.

• Tuberculosis and Respiratory Diseases
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• v.53 no.5
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• pp.519-529
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• 2002

Background : The therapeutic effects of surfactants on acute lung injury derive not only from their recruiting action on collapsed alveoli but also from their anti-inflammatory action in the alveolar sapce. This study evaluated the anti-inflammatory action of a surfactant in an acute lung injury model of rats by neutrophils were recollected from the BAL fluid and the NF-${\kappa}B$ activity of the neutrophilic nuclear protein was evaluated. Methods : Male Sprague-Dawley rats weighing approximately 300 gram were divided into 3 groups, which consisted of 6 rats respectively. In the control group, normal saline(3ml/kg) was instilled into the trachea twice with 30 minute interval. In two other groups, acute lung injury was induced by the intra-tracheal instillation of LPS(5mg/kg). Thirty minutes later, either a surfactant(ST group; 30mg/kg) or normal saline(NT group: 3ml/kg) was instilled via the trachea. Twenty-four hours after the LPS instillation, the BAL fluid was retrieved to measure the WBC count and cytokine(IL-$1{\beta}$ and IL-6) levels. The neutrophils were isolated from the BAL fluid and the nuclear protein was extracted to evaluate the NF-${\kappa}B$ activity using a eletrophoretic mobility shift assay(EMSA). Results : The WBC count of the BAL fluid of the ST group($3,221{\pm}1,914{\times}10^3/{\mu}l$) was higher than that of the control group($356{\pm}275{\times}10^3/{\mu}l$)(p<0.05) and lower than that of the NT group($5,561{\pm}1,757{\times}10^3/{\mu}l$)(p<0.05)). The BAL fluid level of IL-$1{\beta}$ from the NT group($2,064{\pm}1,082pg/ml$) was higher than those of the ST group($360{\pm}234pg/ml$)(p<0.05) and the control group(0pg/ml)p<0.05) and control group($49{\pm}62pg/ml$)(p<0.05). The NF-${\kappa}B$ activity of the neutrophilic nuclear protein in the ST group and NT group was similar. Conclusion : The surfactant, attenuates the alveolar inflammation in the acute lung injury of rats model. However, its anti-inflammatory action does no't appear to be mediated by the inhibition of NF-${\kappa}B$ activity.

• Tuberculosis and Respiratory Diseases
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• v.51 no.3
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• pp.248-259
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• 2001

Background : In diagnosis or monitor of the airway obstruction in bronchial asthma, the measurement of $FEV_1$ in the standard method because of its reproducibility and accuracy. But the measurement of peak expiratory flow(PEF) by peak flow meter is much simpler and easier than that of $FEV_1$ especially in children. Yet there have been still no data of the predicted normal values of PEF measured by peak flow meter in Korean children. This study was conducted to provide equations to predict the normal value of PEF and correlation between PEF and $FEV_1$ in healthy children. Method : PEF was measured by MiniWright peak flow meter, and the forced expiratory volume and the maximum expiratory flow volume curves were measured by Microspiro HI 501(Chest Co.) in 346 healthy children(age:5-16 years, 194 boys and 152 girls) without any respiratory symptoms during 2 weeks before the study. The regression equations for various ventilatory parameters according to age and/or height, and the regression equations of $FEV_1$ by PEF were derived. Results : 1. The regression equation for PEF(L/min) was: $12.6{\times}$age(year)+$3.4{\times}$height(cm)-263($R^2=0.85$) in boys, and $6{\times}$age(year)+$3.9{\times}$height(cm)-293($R^2=0.82$) in girls. 2. The value of FEFmax(L/sec) derived from the maximum expiratory flow volume curves was multiplied by 60 to compare with PEF(L/min), and PEF was faster by 125 L/min in boys and 118 L/min in girls, respectively. 3. The regression equation for $FEV_1$(ml) by PEF(L/min) was:$7{\times}$PEF-550($R^2=0.82$) in boys, and $5.8{\times}$PEF-146 ($R^2=0.81$) in girls, respectively. Conclusion : This study provides regression equations predicting the normal values of PEF by age and/or height in children. And the equations for $FEV_1$, a gold standard of ventilatory function, was predicted by PEF. So, in taking care of children with airway obstruction, PEF measured by the peak flow meter can provide useful information.

• The Journal of the Petrological Society of Korea
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• v.8 no.2
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• pp.106-124
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• 1999

In the Cheongju-Minwon area which occupies the middle part of the Ogcheon Metamorphic Belt, three metamorphic events(M1, M2, M3) had occurred. Intermediate P/T type M2 regional metamorphism formed prevailing mineral assemblages in the study area. Low PIT type M3 contact metamorphism occurred due to the intrusion of granites after M2 metamorphism. M1 metamorphism is recognized by inclusions within garnet. During M2 metamorphism, the metamorphic grade increased from the biotite zone in the southeastern part to the garnet zone in the northwestern part of the study area. This result is similar to the metamorphic evolution of the southwestern part of the Ogcheon Metamorphic Belt. Garnets in the garnet zone are classified into two types; Type A garnet has inclusions whose trail is connected to the foliation in the matrix and Type B garnet has inclusion rich core and inclusion poor rim. Type A garnet formed in the mica rich part with crenulation cleavage whereas Type B garnet formed in the quartz rich part with weak crenulation cleavage. In some outcrops, two types garnets are found together. Compared to the rim of Type A garnet, the rim of Type B garnet is lower in grossular and spessartine contents but higher in almandine and pyrope contents. In some Type B garnets, the inclusion poor part is rimmed by muddy colored or protuberant new overgrowth. In the inclusion poor part and new overgrowth, a rapid increase in grossular and decrease in spessartine is observed. However, the compositional patterns of Type A and B are similar; Ca increases and Mn decreases from core to rim. Two types garnets formed mainly due to the difference of bulk chemistry instead of metamorphic and deformational differences. The metamorphic P-T conditions estimated from Type A garnets are 595-690 OC15.7-8.8 kb, which indicates M2 metamorphism is intermediate P/T type metamorphism. On the other hand, a wide range of P-T conditions is calculated from Type B garnets. The P-T conditions from most Type B garnet rims are 617-690 OC16.2-8.9 kb which also indicates an intermediate P/T type metamorphism. However, at the rim part with flat end or weak overgrowth, grossular content is low and 573-624OC14.7-5.8 kb are estimated. The P-T conditions calculated from plagioclase and biotite inclusions in garnet are 460-500 0C/1.9-3.0 kb. The P-T conditions from rim part with weak overgrowth and inclusions within garnet, indicate that low P/T type M1 regional metamorphism might have occurred before intermediate P/T type M2 regional metamorphism. The P-T conditions estimated from samples which had undergone low PIT type M3 metamorphism strongly, are 547-610 0C/2.1-5.0 kb.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.280-290
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• 1984

An extensive study has been made on the relationship between the freshness and the compositions of the muscle protein of prawn, Pandalus japonica during the storage under partially frozen condition. The variations of the subunit distribution for sarcoplasmic protein and myofibrillar protein extracted from the samples by changes of freshness were discussed by sodium dodecylsulfate-poly-acrylamide gel (SDS-PAG) electrophoresis. On the other hand, the denaturation constant ($K_D$) of the myofibrillar protein extracted from the prawn stored at $-3^{\circ}C\;and\;-20^{\circ}C$ were successively compared. The prawn muscle contained about $18\%$ of protein with the composition of $32\%$ in sarcoplasmic protein, $56\%$ in myofibrillar protein, $10\%$ in residual intracellular protein and $2\%$ in stroma. The indices for estimating freshness of the muscle were approached to the early stage of putrefaction on the 26th day of the storage with $25.29mg\%$ of total volatile basic nitrogen, $31.36\%$ of K-value and 8.83 of pH. The content of the myofibrillar protein was remarkably decreased with the time during the storage while that of residual intracellular protein was increased. The $K_D$ values of the myofibrillar protein were $9.03{\times}10^{-6}sec^{-1}\;at\;-3^{\circ}C\;and\;4.42{\times}10^{-6}sec^{-1}\;at\;-20^{\circ}C$. The results of the analysis of SDS-PAG electrophoretograms indicated that the sarcoplasmic protein and the myofibrillar protein were composed of 12 subunits and 17 subunits in the muscle of instantaneously killed prawn ana were changed into 8 subunits and 22 subunits in the muscle stored for 26 days, respectively. It is noticeable that 30,000, 41,000, 107,000, 136,000, 170,000 173,000, 185,000, and 198,000 daltons of the newly appeared 8 subunits were found in the myofibrillar protein from the prawn muscle stored for 26 days. The amino acid composition of the muscle protein showed that the most of amino acids were slightly decreased with the days of the storage. With respect to the free amino acid composition of the muscle of instantaneously killed prawn, glycine, proline, arginine, alanine and taurine comprised $93\%$ of the total free amino acids. Taurine, valine, leucine, phenylalanine, serine, lysine, methionine, isoleucine and histidine were increased during the storage period but exceptionally proline was decreased.

• Korean Journal of Human Ecology
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• v.14 no.2
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• pp.313-319
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• 2005

This survey was conducted in order to obtain the basic data for desirable consumption habits through investigation and analysis of university students' fast food consumption behaviors. Questionnaires were collected from a total of 374 male and female students living in big or small and medium-sized cities in August, 2004. The contents surveyed were utilization and expenses of fast foods, choice of fast foods, relationship between fast foods and a diet, and characteristics of fast food restaurants. The results obtained are summarized as follows: 1. The ratio of the surveyees varied according to gender, residence, and the size of a city they're living in. For example, males took up 48.66% of the surveyees, while females did 51.34%. The ratio of residents in apartments and stand-alone houses was 54.81% and 45.19% each. 47.33% of the respondents were living in big cities, while 52.67% of them in small and medium-sized cities. 2. 70.1% of the surveyees responded that they are with friends when having fast foods. There was a highly significant difference between male and female in the type of eating companions (p<0.001). The average number of days that they eat fast foods was 1 to 2 times a week, which accounted for 63.7% of the respondents. However, in the case of eating foods, there was no significant differences between two sexes. 3. 64.2% of the surveyees paid more than 20,000 won to buy fast foods for a week, which showed no significant differences between genders. They tend to split a bill, rather than one person pays all. There was a highly significant difference between genders in paying method (p<0.001). 4. 52.1 % of the respondents chose a menu themselves. Their most favored food was chickens (26.5%), which showed a statistically significant difference between genders (p<0.001). 46.8% of them preferred coke as a drink, which had no significant difference between genders. 42.2% of the surveyees had fast foods between lunch and dinner, which also had no significant difference between genders. The most important factor in choosing a menu was its taste (62.8%), which indicated a significant difference between males and females (p<0.05). 5. The preference to fast foods was due to the influence of western culture (36.4%) and eating-out habits (29.1%), which was significantly different between genders (p<0.05). Those who eat fast foods answered they have normal weight and normal body type (49.5%). 24.3% of them were relatively fat with significant difference between genders (p<0.05). 63.4% of the surveyees thought themselves not picky with foods, and there was a significant difference between genders (p<0.05). 78.3% of them mostly preferred franchise restaurants because they are convenient and cheap.

• Korean Journal of Poultry Science
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• v.40 no.2
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• pp.121-127
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• 2013

This work was carried to evaluate production efficiency factor, carcass yield and meat quality with weeks of Large-type Korean native ducks. Korean native ducks (n = 90) from National Institute of Animal Science (RDA, Korea) were used in this work. Ninety ducks were divided into 6 groups (15 birds/group) and were fed with meat-type duck diets for 8 wk old. When ducks grew at specific wk (6, 7 and 8 weeks), 2 ducks per group were slaughtered at 6, 7 and 8 wk old. Production efficiency factor, carcass yield, partial meat and meat quality were researched in this work. There was no significant difference on livability with weeks, but body weight at 7 and 8 wk old was higher than that at 6 wk old (P<0.05). Feed conversion ratio at 6, 7 and 8 wk old were 2.25, 2.69 and 3.21, respectively, so there was significant difference with weeks (P<0.05). Production efficiency factor at 6, 7 and 8 wk old were 256.6, 199.8 and 153.0, respectively, so there was significant difference with weeks (P<0.05). Carcass yield at 8 wk old was higher than that at 6 and 7 wk old as 73.5% (P<0.05). Lightness at 6, 7 and 8 wk were 41.8, 39.0 and 38.1, respectively, and that at 6 wk old was the higher than other weeks (P<0.05). There was no significant difference on redness at 6, 7, and 8 wk old (P>0.05) and yellowness at 8 wk old was higher compared to other weeks (P<0.05). Cooking loss was the highest at 6 wk old as 31.6%, but water holding capacity was the highest at 8 wk old (P<0.05). There was no significant difference on shear force among weeks. pH at 6 wk old was the lower than that of other weeks as 5.84. Moisture content significantly decreased with weeks (P<0.05) and fat content at 8 wk was the highest as 1.88% (P<0.05). Protein content significantly increased with weeks until 20.9% at the age of 8 wk (P<0.05). Ash content at 7 and 8 wk old was the higher than that at 6 wk old (P<0.05). There was no significant difference on juiciness, tenderness, and flavor with weeks. Finally, these results may provide that shipping time at 7 wk old preferred to that at 6 and 7 wk old, but further research was needed because of deficiency of data.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.4
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• pp.193-216
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• 2020

Due to the recent mid- to long-term slump and falling growth rates in the global economy, interest in organizational structures that create new products or services as a new alternative to survive and develop in an opaque environment both internally and externally, and enhance organizational sustainability through changes in production methods and business innovation is increasing day by day. In this atmosphere, we agree that the growth of small and medium-sized venture companies has a significant impact on the national economy, and various efforts are being made to enhance the technological innovation capabilities of the members so that these small and medium-sized venture companies can enhance and sustain their performance. The purpose of this study is also to investigate how the technological innovation capabilities of small and medium-sized venture companies correlate with the performance of knowledge management and to analyze the role of network capabilities to organize the strategic activities of enterprise to obtain the resources and organizational capabilities to be used for value creation from external networks. In other words, research was conducted on the impact of technological innovation capabilities of small and medium venture companies on knowledge management performance by using network capabilities as parameters. Therefore, in this study, we would like to verify the hypothesis that innovation capabilities will have a positive impact on knowledge management performance by using network capabilities of small and medium venture companies. Economic activities based on technological innovation capabilities should respond quickly to new changes in an environment where uncertainty has increased, and lead to macro-economic growth and development as well as overcoming long-term economic downturns so that they can become the nation's new growth engine as well as sustainable growth and survival of the organization. In addition, this study was conducted by setting the most important knowledge management performance within the organization as a dependent variable. As a result, R&D and learning capabilities among technological innovation capabilities have no impact on financial performance. In contrast, it was shown that corporate innovation activities have a positive impact on both financial and non-financial performance. The fact that non-financial factors such as quality and productivity improvement are identified in the management of small and medium-sized venture companies utilizing their technological innovation capabilities is contrary to a number of studies by those corporate innovation activities affect financial performance during prior research. The reason for this result is that research companies have been out of start-up companies for more than seven years, but sales are less than 10 billion won, and unlike start-up companies, R&D and learning capabilities have more positive effects on intangible non-financial performance than financial performance. Corporate innovation activities have been shown to have a positive (+) impact on both financial and non-financial performance, while R&D and learning capabilities have a positive (+) impact on financial performance by parameters of network capability. Corporate innovation activities have been shown to have no impact on both financial and non-financial performance, and R&D and learning capabilities have no impact on non-financial performance. It could be seen that the parameter effects of network competency are limited to when R&D and learning competencies are derived from quantitative financial performance. It could be seen that the parameter effects of network competency are limited to when R&D and learning competencies are derived from quantitative financial performance.

• Investigative Magnetic Resonance Imaging
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• v.8 no.2
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• pp.100-108
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• 2004

Purpose : Early degeneration of articular cartilage is accompanied by a loss of glycosaminoglycan (GAG) and the consequent change of the integrity. The purpose of this study was to biochemically quantify the loss of GAG, and to evaluate the $Gd(DTPA)^{2-}$-enhanced, and T1, T2, rho relaxation map for detection of the early degeneration of cartilage. Materials and Methods : A cartilage-bone block in size of $8mm\;\times\;10mm$ was acquired from the patella in each of three pigs. Quantitative analysis of GAG of cartilage was performed at spectrophotometry by use of dimethylmethylene blue. Each of cartilage blocks was cultured in one of three different media: two different culture media (0.2 mg/ml trypsin solution, 1mM Gd $(DTPA)^{2-}$ mixed trypsin solution) and the control media (phosphate buffered saline (PBS)). The cartilage blocks were cultured for 5 hrs, during which MR images of the blocks were obtained at one hour interval (0 hr, 1 hr, 2 hr, 3 hr, 4 hr, 5 hr). And then, additional culture was done for 24 hrs and 48 hrs. Both T1-weighted image (TR/TE, 450/22 ms), and mixed-echo sequence (TR/TE, 760/21-168ms; 8 echoes) were obtained at all times using field of view 50 mm, slice thickness 2 mm, and matrix $256\times512$. The MRI data were analyzed with pixel-by-pixel comparisons. The cultured cartilage-bone blocks were microscopically observed using hematoxylin & eosin, toluidine blue, alcian blue, and trichrome stains. Results : At quantitation analysis, GAG concentration in the culture solutions was proportional to the culture durations. The T1-signal of the cartilage-bone block cultured in the $Gd(DTPA)^{2-}$ mixed solution was significantly higher ($42\%$ in average, p<0.05) than that of the cartilage-bone block cultured in the trypsin solution alone. The T1, T2, rho relaxation times of cultured tissue were not significantly correlated with culture duration (p>0.05). However the focal increase in T1 relaxation time at superficial and transitional layers of cartilage was seen in $Gd(DTPA)^{2-}$ mixed culture. Toluidine blue and alcian blue stains revealed multiple defects in whole thickness of the cartilage cultured in trypsin media. Conclusion : The quantitative analysis showed gradual loss of GAG proportional to the culture duration. Microimagings of cartilage with $Gd(DTPA)^{2-}$-enhancement, relaxation maps were available by pixel size of $97.9\times195\;{\mu}m$. Loss of GAG over time better demonstrated with $Gd(DTPA)^{2-}$-enhanced images than with T1, T2, rho relaxation maps. Therefore $Gd(DTPA)^{2-}$-enhanced T1-weighted image is superior for detection of early degeneration of cartilage.