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Antioxidant activity and suppression of pro-inflammatory mediator of Corni fructus extracts in activated RAW 264.7 macrophage (산수유(Corni fructus) 분획 추출물의 항산화 활성 및 RAW 264.7 대식세포에서 염증매개물질 억제 효과)

  • Kim, Ye Jin;Son, Dae-Yeul
    • Food Science and Preservation
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    • v.23 no.6
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    • pp.876-882
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    • 2016
  • The antioxidant and anti-inflammatory effects of Corni fructus extracts (CEF, EtOAc extraction; CBF, buthanol extraction; CWF, water extraction) were investigated. The total phenolics of CEF (173.3 mg TAE/g) were significantly higher than those of CWF (26.7 mg TAE/g) and CBF (94.8 mg TAE/g). DPPH and ABTS free radical scavenging activity of CEF (DPPH: $RH_{50}$; $25.1{\mu}g/mL$, ABTS: $RC_{50}$; $36.1{\mu}g/mL$) showed even higher than that of BHA and ${\alpha}-tocopherol$ used as positive control. All three Corni fructus extracts in the concentration of $1{\sim}100{\mu}g/mL$ were effective inhibitors of NO and prostaglandin $E_2$ ($PGE_2$). NO production was inhibited 71.3~92.2% by CEF, 76.8~85.5% by CBF and 74.4~96.9% by CWF, respectively. CEF, CBF and CWF ($1{\sim}100{\mu}g/mL$) inhibited also pro-inflammatory cytokines like $TNF-{\alpha}$, $IL-1{\beta}$ and IL-6 very effectively. $TNF-{\alpha}$ was inhibited up to 51.2% by CWF and $IL-1{\beta}$ was inhibited up to 67.1% by CEF. IL-6 was best inhibited by CEF up to 58.9%. This study suggested the potential of Corni fructus for use as an excellent antioxidant substance and inflammatory inhibiting mediators. Therefore CEF, CBF and CWF Corni fructus extracts may be used for therapeutic approach to various inflammatory diseases.

Native Tree Species of Tolerance to Saline Soil and Salt Spray Drift at the Coastal Forests in the West-Sea, Korea (한국 서해안의 내염성 및 내조성 자생수종)

  • Kim, Do-Gyun
    • Korean Journal of Environment and Ecology
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    • v.24 no.2
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    • pp.209-221
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    • 2010
  • This study was carried out to apply basic data of the native trees for planting in the salinity area by the vegetation ecological selection. Which focused on native woody species to the tolerances of saline soil and salt spray drift on the coastal forests in the West-Sea, Korea. The soil salinity($EC_{1:5}$) was 0.11dS$m^{-1}$, ranging of 0.00dS$m^{-1}$~0.68dS$m^{-1}$. The soil salinity was gradually decreasing from Belt I to Belt Ⅳ except the Belt I in some coastal windbreaks. The order of decreasing soil salinity was Belt I>Belt II>Belt III>Belt Ⅳ and the soil salinity was $EC_{1:5}$ 0.14dS$m^{-1}$, 0.11dS$m^{-1}$, 0.10dS$m^{-1}$, and 0.08dS$m^{-1}$, respectively. The total 181 taxa consisted of 52 families, 104 genus, 157 species, and 24 varieties were recorded as the trees tolerating to both soil salinity and salt spray drift. The trees emerged in the highest degree of salinity($EC_{1:5}$ 0.51dS$m^{-1}$) was nothing but appearanced Pinus thunbergii Parl., Smilax china L., Quercus dentata Thunb. ex Murray, Quercus serrata Thunb. ex Murray and so on at the level of singular and ideal value. The emerged trees in the high salinity of $EC_{1:5}$0.41dS$m^{-1}$~0.50dS$m^{-1}$ were Albizia kalkora Prain, Melia azedarach L., Paederia scandens (Lour.) Merr. var. scandens These species were trees of tolerance to saline soil. The emerged woody species in all belts were Pinus rigida Mill., Pinus densiflora Siebold & Zucc., Pinus thunbergii Parl., Juniperus rigida Siebold & Zucc. and so on. The woody species with high important value(I.V.) were Pinus densiflora Siebold & Zucc., Pinus thunbergii Parl., Pseudosasa japonica (Siebold & Zucc. ex Steud.) Makino, Smilax china L., Platycarya strobilacea Siebold & Zucc. var. strobilacea for. strobilacea and so on, which can be classified as highly tolerant native trees to salt spray drift.

Acute Kidney Injury Models: Focus on the Therapeutic Effects of Stem Cell in Preclinical Approach (줄기세포 연구를 위한 급성신장손상 모델)

  • Nam, Hyun-Suk;Woo, Jae-Seok;Woo, Heung-Myong
    • Journal of Veterinary Clinics
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    • v.27 no.5
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    • pp.533-539
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    • 2010
  • Stem cell-based therapy is under intensive investigation to treat acute renal failure (ARF). The purpose of this study was to evaluate available ARF models, and suggest a model appropriate to therapeutic evaluation of the stem cells in preclinical approach by determining the optimum concentration of nephrotoxic agents and duration of ischemia induction. Three different types of available acute kidney injury (AKI) animal models were analyzed using rats: Cisplatin (saline, 5 and 7.5 mg/kg, IP) or glycerol (saline, 8 and 10 ml/kg, IM)-induced nephrotoxicity as toxic models and ischemia-induced (sham, 35 and 45 minutes) nephropathy as an ischemic model. The relevance and applicability to investigate especially the regenerative ability of stem cells were evaluated regarding morphology, renal function and survival at this time point. In the point of renal function, 10 ml glycerol/kg and 7.5 mg cisplatin/kg model in toxic models and 45 min model in ischemia models showed significant decrease for the longer observation time compared to 8 ml glycerol/kg, 5 mg cisplatin/kg and the 35 min ischemia models, respectively. All groups were observed no mortality except 45 min-ischemia model with 50% survival. Histological significant alterations including cast formation in the tubular lumen, tubular necrosis and apoptosis were revealed on the second day in either ischemiaor glycerol-induced models, and on day 5 in cisplatin-induced models. The results indicate that ischemia 35 min-, cisplatin 7.5 mg/kg- and glycerol 10 ml/kg-induced AKI would be ideal animal models to monitor a outcome parameter related to the therapeutic effects on renal function with noninvasive techniques in the same animal at multiple time points. Our findings also suggest that the best time points for the functional or histological interpretation of renal will be on day 2 in both glycerol- and ischemia-induced AKI models and on day 5 in cisplatin-induced AKI.

Removal of $^{210}Po$ and $^{234}Th$ from Seawater at the East-southern Coastal Region of Korea Peninsula in Spring (춘계 한국 동해남부 연안해역에서 해수중 $^{210}Po$$^{234}Th$의 제거)

  • LEE Haeng-Pil;YANG Han-Soeb;KIM Kee-Hyun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.29 no.3
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    • pp.332-344
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    • 1996
  • The vertical profiles of the natural $^{210}Po,\;^{210}Pb\;and\;^{234}Th$, activities were measured at the upper 150 m or 200 m of water column from west-east intersection in the east-southern coastal area of the Korea Peninsula during the period from 26 to 29 April 1994 to compare the removal rates (residence time) and removal processes for $^{210}Po\;and\;^{234}Th$. At the inshore stations, the $^{210}Po$ activity was generally higher in the thermocline and its under layer than in the surface mixed layer, while represented the reversed pattern at the offshore stations. However, the $^{210}Pb$ activity decreased generally with depth. Also, the activity of $^{210}Po$ relative to its parent $^{210}Pb$ was deficient in the water column above the main thermocline, but was slightly excess or close to equilibrium in the thermocline and its under layer. The vertical profiles for the activity of $^{210}Pb$ relative to its parent $^{226}Ra$ showed the reversed pattern with the vertical variation of $^{210}Po$ excess (or deficiency). The $^{234}Th$ activity was significantly lower in the surface mixed layer and thermocline than in the deeper layer. The residence time of $^{210}Po$ ranged from 1 to 4 years at the five stations except station E8 that showed yet long residence time (approximately 10 years). The long residence time at the station E8 may resulted from the thicker surface mixed layer and subsequent the vertical mixing of $^{210}Po$ which was recycled in the lower surface mixed layer compared to at the other stations. Also, the residence time of $^{210}Po$ was shorter at the inshore stations than at the offshore stations. However, the residence time of $^{234}Th$ ranged from 52 to 74 days at all station without the significant variation, was very much shorter relative to the residence time of $^{210}Po$. The correlation between the removal rate of dissolved $^{234}Th$ and the concentration of total suspended matter (TSM) was generally positive. Therefore, it seems that the major route of the removal mechanism of $^{234}Th$ from seawater in the surface mixed layer is via adsorption onto suspended particle surfaces (most likely inorganic particles) and subsequent settling to the bottom layer. Between the removal rate of dissolved $^{210}Po$ and the concentration of chlorophyll-a was positively good correlation. Consequently, most likely the removal of $^{210}Po$ may be occurred by uptake to organisms (mainly such as planktonic debris or fecal pellets) and subsequent settling.

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Changes of Digestive Enzyme Activity in Slime Flounder, Micromus achne Larvae with Growth and Development (찰가자미, Micromus achne 자어의 성장과 발달에 따른 소화효소 활성의 변화)

  • 박상언;임한규;한현섭;이종하;임영수;이종관;이상민
    • Journal of Aquaculture
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    • v.16 no.4
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    • pp.233-239
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    • 2003
  • Growth and activities of digestive enzymes in slime flounder (Microstomus achne) larvae were measured from hatching to near the end of larval development (day 58). Larvae reared under starved and fed conditions and the changes of acid phosphatase (ACPase) specific activity, alkaline phosphatase (ALPase) specific activity, trypsin-like enzyme activity and pepsin-like enzyme activity were described with growth and developmental stage of larvae. Total length of the starved larvae was gradually increased for 7 days post hatching and then almost unchanged. Total length of the fed larvae ranged from 5.13$\pm$0.178 mm at the day of hatching to 13.43$\pm$1.395 mm at 58 days after hatching. In starved group, dry body weight decreased from 0.l0$\pm$0.020 mg at the day of hatching to 0.05$\pm$0.012 mg at 12 days after hatching. Dry body weight of fed larvae decreased during the prelarva stage like starved group and then gradually increased. ACPase and ALPase specific activity in the starved larvae increased until all larvae died, however those activities in the fed larvae increased until 20 days and then decreased until 58 days after hatching, with no significant difference between groups. Trypsin-like enzyme activity in the starved larvae was unchanged until 3 days and then was the highest on 5 days after hatching, but not detected after completion of yolksac absorption. Those of fed larvae decreased until 3 days and sharply increased until completion of yolksac absorption. The highest trypsin-like enzyme activity in the fed group was observed at 20 days after hatching. Trypsin-like enzyme activity in the fed larvae was significantly higher than that in the starved larvae from 8 days after hatching. Pepsin-like enzyme activity was increased in 5 days after hatching in both groups. There was significant difference at 8 and 10 days after hatching between both groups. Based on above results, digestive enzyme activities were correspondingly changed to a growth and morphological transformation. Trypsin-like enzyme and pepsin-like enzyme activities are able to be a useful indices for health and growth status in larval slime flounder, because there was significant difference in digestive enzyme activities with developmental stages, growth or feed supply.

A Study on Correlation among Empowerment, Job Satisfaction and Turnover Intention of Food Service Industry Employees (외식업체 종사자들의 임파워먼트가 직무만족과 이직의도에 미치는 영향에 관한 연구)

  • Lee, Jong-Ho
    • Culinary science and hospitality research
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    • v.18 no.5
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    • pp.113-128
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    • 2012
  • This research was conducted targeting 269 employees working in the hotel and food service industry in the Busan area to provide human resources policy implications for food service companies by understanding the causal relationship between the empowerment of foodservice industry employees and job satisfaction and turnover intent. To achieve the research purpose, this research identified the demographic characteristics through a frequency analysis, obtained reliability and validity through a factor and reliability analysis, attaining a meaningful result in the significance level of p<.01 in all factors by conducting a correlation analysis to understand the overall relationship between the variables. As a result of the multiple regression analysis to verify a hypothesis, the explanatory adequacy of the regression model for the effect of self-determination and meaning, the sub-factors of empowerment, on job satisfaction was 34.6%, and the self-determination and meaning was respectively analyzed as (${\beta}$=.125, p<.05) and (${\beta}$=.511, p<.001), thus, the hypothesis that the empowerment of employees in the food service industry has a positive (+) effect was selected. In addition, the multiple regression analysis was conducted to examine the effect that empowerment (self-determination, meaning) has on job turnover intent, and as a result, the explanatory adequacy of the regression model was 11.2%, the self-determination was ${\beta}$=-.024, showing that it was not analyzed as a statistically meaningful result, and the meaning was analyzed as(${\beta}$=-320,p<.001). Thus, the hypothesis that the empowerment of employees in the food service industry has a negative (-) effect on job turnover intent was partially selected. In the regression analysis result of the effect of job satisfaction on turnover intent, the explanatory adequacy of the entire regression model appearing in the entire analysis was 25.3%, and the job satisfaction was analyzed as (${\beta}$=-.503,p<.001). Thus, the hypothesis that job satisfaction has a negative (-) effect on job turnover intent was selected.

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VKOSPI Forecasting and Option Trading Application Using SVM (SVM을 이용한 VKOSPI 일 중 변화 예측과 실제 옵션 매매에의 적용)

  • Ra, Yun Seon;Choi, Heung Sik;Kim, Sun Woong
    • Journal of Intelligence and Information Systems
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    • v.22 no.4
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    • pp.177-192
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    • 2016
  • Machine learning is a field of artificial intelligence. It refers to an area of computer science related to providing machines the ability to perform their own data analysis, decision making and forecasting. For example, one of the representative machine learning models is artificial neural network, which is a statistical learning algorithm inspired by the neural network structure of biology. In addition, there are other machine learning models such as decision tree model, naive bayes model and SVM(support vector machine) model. Among the machine learning models, we use SVM model in this study because it is mainly used for classification and regression analysis that fits well to our study. The core principle of SVM is to find a reasonable hyperplane that distinguishes different group in the data space. Given information about the data in any two groups, the SVM model judges to which group the new data belongs based on the hyperplane obtained from the given data set. Thus, the more the amount of meaningful data, the better the machine learning ability. In recent years, many financial experts have focused on machine learning, seeing the possibility of combining with machine learning and the financial field where vast amounts of financial data exist. Machine learning techniques have been proved to be powerful in describing the non-stationary and chaotic stock price dynamics. A lot of researches have been successfully conducted on forecasting of stock prices using machine learning algorithms. Recently, financial companies have begun to provide Robo-Advisor service, a compound word of Robot and Advisor, which can perform various financial tasks through advanced algorithms using rapidly changing huge amount of data. Robo-Adviser's main task is to advise the investors about the investor's personal investment propensity and to provide the service to manage the portfolio automatically. In this study, we propose a method of forecasting the Korean volatility index, VKOSPI, using the SVM model, which is one of the machine learning methods, and applying it to real option trading to increase the trading performance. VKOSPI is a measure of the future volatility of the KOSPI 200 index based on KOSPI 200 index option prices. VKOSPI is similar to the VIX index, which is based on S&P 500 option price in the United States. The Korea Exchange(KRX) calculates and announce the real-time VKOSPI index. VKOSPI is the same as the usual volatility and affects the option prices. The direction of VKOSPI and option prices show positive relation regardless of the option type (call and put options with various striking prices). If the volatility increases, all of the call and put option premium increases because the probability of the option's exercise possibility increases. The investor can know the rising value of the option price with respect to the volatility rising value in real time through Vega, a Black-Scholes's measurement index of an option's sensitivity to changes in the volatility. Therefore, accurate forecasting of VKOSPI movements is one of the important factors that can generate profit in option trading. In this study, we verified through real option data that the accurate forecast of VKOSPI is able to make a big profit in real option trading. To the best of our knowledge, there have been no studies on the idea of predicting the direction of VKOSPI based on machine learning and introducing the idea of applying it to actual option trading. In this study predicted daily VKOSPI changes through SVM model and then made intraday option strangle position, which gives profit as option prices reduce, only when VKOSPI is expected to decline during daytime. We analyzed the results and tested whether it is applicable to real option trading based on SVM's prediction. The results showed the prediction accuracy of VKOSPI was 57.83% on average, and the number of position entry times was 43.2 times, which is less than half of the benchmark (100 times). A small number of trading is an indicator of trading efficiency. In addition, the experiment proved that the trading performance was significantly higher than the benchmark.

Selection and Mechanism of Anti-Obesity Agents from Natural Products Based on Anti-Angiogenesis (신생혈관형성억제작용을 기반으로 한 항비만제제의 선별 및 작용기전)

  • Shin, Jin-Hyuk;Lee, Jin-Hee;Kang, Kyeong-Wan;Hwang, Jae-Ho;Han, Kyeong-Ho;Shin, Tai-Sun;Kim, Min-Yong;Kim, Jong-Deog
    • KSBB Journal
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    • v.24 no.2
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    • pp.122-130
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    • 2009
  • Anti-angiogenic mechanism was examined for anti-obesity agents with the extract of P.radix, P.semen, S.hebra and C.furctus through anti-cell adhesion effect and western blot. Cell adhesion molecules, VCAM-1 was supressed with the order of P.radix (0.2 ppm, 125%) > P.semen (0.5 ppm, 100%) > S.hebra (5.0 ppm, 114%) > C. furctus (5.0 ppm, 111.8%), ICAM-1 was inhibited by P.radix (0.25 ppm, 130%) > P.semen (0.5 ppm, 100%) > S.hebra (5.0 ppm, 138%) > C. furctus (5.0 ppm, 66.7%), E-Selectin was also supressed P.radix (0.25 ppm, 100%) > P.semen (1.0 ppm, 128%) > S.hebra (5.0 ppm, 120%) > C. furctus (5.0 ppm, 100.7%). And signal molecules, VE-cadherin was supressed by P.radix and S.hebra, ${\beta}$-catenin was inhibited by P.radix, and Akt was supressed all these 4 kinds of natural products. These P.radix, P.semen, S.hebra and C.furctus were showed the possibility of anti-obesity agents based on anti-angiogenesis.

Spermatozoa Characteristics of Streptozotocin-induced Diabetic Wistar Rat: Acrosome Reaction and Spermatozoa Concentration (Streptozotocin으로 유발된 당뇨병성 Wistar Rat 정자의 첨체반응 및 수 변화 특성)

  • Cheon, Yong-Pil;Kim, Chung-Hoon;Kang, Byung-Moon;Chang, Yoon-Seok;Nam, Joo-Hyun;Kim, Young-Soo;Gye, Myung-Chan;Kim, Moon-Kyoo;Kim, Kil-Soo
    • Clinical and Experimental Reproductive Medicine
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    • v.26 no.1
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    • pp.89-96
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    • 1999
  • Some of the information concerning sexual function in the male diabetes has been focused upon the problems of endocrine or semen parameters. However, the characteristics of acrosome reaction and spermatozoa concentration at the epididymis and vas deferens have scarcely been studied, and the causes of the infertility has not been critically identified. So, we designed to inspect the spermatozoa concentration and the characteristics of acrosome reaction at epididymis and vas deferens of diabetic Wistar rat induced by streptozotocin (STZ, 70 mg/kg, ip). Experimental animal was sacrificed at 3 days and 14 days after the STZ injection. In the diabetes-induced rat, the levels of insulin and glucose had a pattern of inverse proportion. The spermatozoa concentrations in caput and corpus epididymis were significantly decreased in all diabetic condition. In cauda epididymis, however, there was significant decrease in sperm concentration at 14 days onward. In diabetic rat, the spontaneous reaction rate of spermatozoa of cauda and vas deferens were significantly higher than the control group. The ARIC (acrosome reaction to ionophore challenge) value of caudal sperm was 28.7 at control, 22.1 at 3 days, and 8.3 at 14 days. In the present study the spermatozoa concentration was decreased and the spontaneous reaction rate was increased by diabetes. In ARIC-test, it is revealed that the fertility of spermatozoa of 14 days group was lower than control or 3 days group. Diabetes mellitus may be provoke the decreased fertilization rate and subsequent infertility and subsequent infertility.

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Periodontal Management strategies for the future in Korea (2000년대 치주처치의 전략)

  • Chung, Hyun-Ju;Son, Sung-Hee
    • Journal of Periodontal and Implant Science
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    • v.27 no.3
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    • pp.533-547
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    • 1997
  • In periodontics, much progress was made in the understanding of periodontal disease from 1960s to 1980s and in prevention and management of periodontal disease since the end of 1980s. This presentation will discuss about the prevalence of periodontal disease, treatment need, and provision of periodontal treatment in Korea, and how we could manage the periodontal disease efficiently in the future. According to an epidemiological study in Korea, periodontal disease(including gingivitis) was present in 82% of general population and periodontitis in 30-40% in adult population over 30y and juvenile periodontitis in 0.1% of adolescents. If we consider that at least 17% of these patients may have recurrent or refractory forms, there is obviously an abundance of disease that needs treatment, As a result of increase in life expectancy, senile population over 65 y will be increased from 6% in 1996 to 6.9% in 2000, and tooth retention rate and periodontal treatment need are expected to increase. Periodontists need all the help they can get from the general dentists to control periodontal disease. As for provision, postgraduate course in periodontics started in 1957 in Korea and produced over 700 specialized dentists in periodontics. One report indicated that the periodontists as well as general practitioners did periodontal therapy on only a few periodontal patients, because of specific control by current medical insurance system in Korea. Comprehensive periodontal examination is rarely done in local dental clinic. Therefore, enhancement of periodontal care in medical insurance system and education of simplified periodontal examination such as Periodontal Screening & Recording will make dentists diagnose and manage the management of adult patients is based on the recognition that there are multiple diseases, including gingivitis, chronic adlt periodontitis, and other more aggressive forms of periodontitis, and requires the earliest possible recognition of these three disease categories. In this presentation, we discuss practical approach using PSR to diagnose, manage and refer the patients, to facilitate the separation of the simple from the complex and the predictable from the unpredictable form of periodontal diseases and to integrate diagnostic and therapeutic techniques into private practice today.

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