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Comparison of Lens Dose in accordance with Bismuth shielding and Patient position in Brain perfusion CT (Brain Perfusion CT에서 Bismuth 차폐와 환자의 자세 변화에 따른 수정체 선량 비교 연구)

  • Gang, Eun Bo
    • Journal of the Korean Society of Radiology
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    • v.12 no.1
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    • pp.47-52
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    • 2018
  • Brain perfusion CT scanning is often employed usefully in clinical conditions as it accurately and promptly provides information about the perfusion state of patients having acute ischemic stroke with a lot of time constraints and allows them to receive proper treatment. Despite those strengths of it, it also has a serious weakness that Lens may be exposed to a lot of dose of radiation in it. In this study, as a way to reduce the dose of radiation to Lens in brain perfusion CT scanning, this researcher conducted an experiment with Bismuth shielding and change of patients' position. TLD (TLD-100) was placed on both lens using the phantom (PBU-50), and then, in total 4 positions, parallel to IOML, parallel to IOML (Bismuth shielding), parallel to SOML, and parallel to SOML (Bismuth shielding), brain perfusion scanning was done 5 times for each position, and dose to Lens were measured. Also, to examine how the picture quality changed in different positions, 4 areas of interest were designated in 4 spots, and then, CT number and noise changes were measured and compared. According to the results of conducting one-way ANOVA on the doses measured, as the significance probability was found to be 0.000, so there was difference found in the doses of radiation to crystalline lenses. According to the results of Duncan's post-hoc test, with the scanning of being parallel to IOML as the reference, the reduction of 89.16% and 89.66% was observed in the scanning of being parallel to SOML and that of being parallel to SOML (Bismuth shielding) respectively, so the doses to Lens reduced significantly. Next, in the scanning of being parallel to IOML (Bismuth shielding), the reduction of 37.12% was found. According to the results, reduction in the doses of radiation was found the most significantly both in the scanning of being parallel to SOML and that of being parallel to SOML (Bismuth shielding). With the limit of the equivalent dose to Lens as the reference, this researcher conducted comparison with the dose to occupational exposure and dose to Public exposure in the scanning of being parallel to IOML and found 39.47% and 394.73% respectively; however in the scanning of being parallel to SOML (Bismuth shielding), considerable reduction was found as 4.08% and 40.8% respectively. According to the results of evaluation on picture quality, every image was found to meet the evaluative standards of phantom scanning in terms of the measurement of CT numbers and noise. In conclusion, it would be the most useful way to reduce the dose of radiation to Lens to use shields in brain perfusion CT scanning and adjust patients' position so that their lens will not be in the field of radiation.

A new diagnostic method for diabetic neuropathy using $TcpO_2$ ($TcpO_2$ 이용한 당뇨병성 신경병증 환자의 조기진단)

  • Hong, Hyun-Ki;Kim, Sung-Woo;Nam, Ki-Chang;Cha, Eun-Jong;Kim, Deok-Won
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.44 no.3
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    • pp.1-8
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    • 2007
  • PDiabetic neuropathy is one of the most common diabetes related complications including diabetic nephropathy and retinopahty. In clinical practices, nerve conduction velocity (NCV) has been used as a standard method for diagnosing diabetic neuropathy. However, it applies maximum current of 100mA to nerves causing stress and pain to patients. In this study, as a non-invasive method, $TcpO_2$ was utilized to investigate the difference and relationship between $TcpO_2$ and $SpO_2$ of normal and diabetic neuropathy subjects. In addition, a new method of diagnosing diabetic neuropathy using $TcpO_2$ is suggested. 50 normal subjects and 50 diabetic patients with neuropathy diagnosed by NCV participated in this study. Parameters used in this study were $TcpO_2$, $TcpCO_2$, and $SpO_2$. As a result of the $TcpO_2$ measurements, statistical significances were found from $TcpO_2$ of hands and feet from normal and patients group(p<0.01). $SpO_2$ measured from index finger of normal and patient groups showed no statistical significance(p>0.05). On the other hand, $SpO_2$ measured from great toes of normal and patient groups showed statistical significance(p<0.01). Correlation coefficient between $SpO_2$ of finger and $TcpO_2$ of hand was 0.400 (p<0.01) and $SpO_2$ of toe and $TcpO_2$ of foot was 0.471(p<0.01). Both correlation values were statistically significant. Sensitivities and specificities of the $TcpO_2$ method were found to be 66 % and 92 %, respectively. If the suggested $TcpO_2$ method is used periodically, prevention and early diagnosis of diabetic neuropathy would be possible.

Prevalence and Characterization of Virulence Genes in Escherichia coli Isolated from Diarrheic Piglets in Korea

  • Kim, Sung Jae;Jung, Woo Kyung;Hong, Joonbae;Yang, Soo-Jin;Park, Yong Ho;Park, Kun Taek
    • Journal of Food Hygiene and Safety
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    • v.35 no.3
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    • pp.271-278
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    • 2020
  • Enterotoxigenic Escherichia coli is one of the major causative infectious agents of diarrhea in newborn and post-weaning pigs and leads to a large economic loss worldwide. However, there is limited information on the distribution and characterization of virulence genes in E. coli isolated from diarrheic piglets, which also applies to the current status of pig farms in Korea. To investigate the prevalence and characterization of virulence genes in E. coli related to diarrhea in piglets, the rectal swab samples of diarrheic piglets (aged 2 d to 6 w) were collected from 163 farms between 2013 and 2016. Five to 10 individual swab samples from the same farm were pooled and cultured on MacConkey agar plates, and E. coli were identified using the API 32E system. Three sets of multiplex PCRs were used to detect 13 E. coli virulence genes. As a result, a total of 172 E. coli isolates encoding one or more of the virulence genes were identified. Among them, the prevalence of individual virulence gene was as follows, (1) fimbrial adhesins (43.0%): F4 (16.9%), F5 (4.1%), F6 (1.7%), F18 (21.5%), and F41 (3.5%); (2) toxins (90.1%): LT (19.2%), STa (20.9%), STb (25.6%), Stx2e (15.1%), EAST1 (48.3%); and (3) non-fimbrial adhesin (19.6%): EAE (14.0%), AIDA-1 (11.6%) and PAA (8.7%), respectively. Taken together, various pathotypes and virotypes of E. coli were identified in diarrheic piglets. These results suggest a broad array of virulence genes is associated with coliform diarrhea in piglets in Korea.

Two-Dimensional Interpretation of Ear-Remote Reference Magnetotelluric Data for Geothermal Application (심부 지열자원 개발을 위한 원거리 기준점 MT 탐사자료의 2차원 역산 해석)

  • Lee, Tae-Jong;Song, Yoon-Ho;Uchida, Toshihiro
    • Geophysics and Geophysical Exploration
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    • v.8 no.2
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    • pp.145-155
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    • 2005
  • A two-dimensional (2-D) interpretation of MT data has been performed for the purpose of fracture detection for geothermal development. Remote stations have been operated in Kyushu, Japan (480 km apart) as well as in Korea (60 km and 165 km apart in 2002 and 2003 data set, respectively). Apparent resistivity and phase curves calculated by remote processing with the Japan remote data showed enough quality for 2-D inversion for the whole frequency range. Remote reference processing with Korea remote reference data also showed quite good continuity in apparent resistivity and phase curves except some noisy frequency bands; around the power frequency, 60 Hz, and around the dead band $10^{-1}Hz\;Hz\;\~1\;Hz$, where the natural EM signal is known to be very weak. Even though the subsurface showed severe three-dimensional (3-D) characteristics in the survey area so that 2-D inversion by itself could not give enough information for deep geological structures, the 2-D inversion for the 5 survey lines showed several common features. The conductive semi-consolidate mudstone layer is dipping from north to south (about 500 m depth on the south and 200 m on the north most part of the survey area). The boundary between the low (L-2) and high (H-2) resistivity anomalies can be thought as a major fault with strike $N15^{\circ}E$, passing through the sites 206, 112 and 414. The shallow (< 1 km) conductive anomalies (L-4) seem to be fracture zones having strike E-W (at site 105) and $N60^{\circ}W$ (at site 434). And there exists a conductive layer in the western and west-southern part of the survey area in the depth below $2\~3\;km$, for which further investigation is to be needed.

A study an actual proof analysis for design management strategy of minor enterprise (중소기업의 디자인 경영 전략을 위한 실증 분석연구)

  • 홍성수;박재연
    • Science of Emotion and Sensibility
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    • v.7 no.1
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    • pp.65-81
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    • 2004
  • With the arrival of the 21th century, the management environments such as the knowledge system, information system, and technology system surrounding small and medium enterprises are being rapidly changed. These rapidly changing the environment of enterprises like the above can be thought rather profitable for the elastic and resiling medium enterprises than large enterprises. Additionally, these environments are recognized as the management circumstances which provide with the change by which medium enterprises equipped with the trustworthy creativity in the 21th century are able to become the main player of the industrial development. The position and role of medium enterprises in the national economical system are very important. The execution of the local autonomy system and the policy to activate the local economy will generally enlarge the power of medium enterprises which are based on the concerned local society more ant more. But, by the standpoint of designer, it is pointed out that there is the problem that the effective application means or the availability of the industrial design was not sufficiently recognized or understood by the manager in enterprises. Notwithstanding the above problem, a lot of domestic small and medium enterprises became to apply the industrial design as the means for improving the competitiveness of their own products in the relatively short time powered by the governmental policy, and moreover both of the concerned partners(the manager and industrial designer) had the opportunity to newly recognize the industrial design and evaluate the availability or problem of the industrial design in the actual aspect. This event means very important change. With the understanding on the above situation, the purpose of this study is to recognize whether the design is strategically applied in the management level of domestic small and medium enterprises, whether the strategical establishment of the design management is performed without any problem, whether the field designer and CEO are well recognizing the design management and what their recognition level is in order to seek the new solution for plenty of problems. Therefore, the actual proof analysis was performed for the field designer and management CEO of small and medium enterprises with the questionnaire survey and direct interview method to understand the actuality of small and medium enterprises.

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Limitations of National Responsibility and its Application on Marine Environmental Pollution beyond Borders -Focused on the Effects of China's Three Gorges Dam on the Marine Environment in the East China Sea- (국경을 넘는 해양환경오염에 대한 국가책임과 적용의 한계 -중국의 산샤댐 건설로 인한 동중국해 해양환경 영향을 중심으로-)

  • Yang, Hee Cheol
    • Ocean and Polar Research
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    • v.37 no.4
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    • pp.341-356
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    • 2015
  • A nation has a sovereign right to develop and use its natural resources according to its policies with regard to development and the relevant environment. A nation also has an obligation not to harm other countries or damage environments of neighboring countries as consequences of such actions of developments or use of natural resources. However, international precedents induce a nation to take additional actions not to cause more damages from the specific acts causing environmental damages beyond national borders, when such acts have economic and social importance. That is to say that there is a tendency to resolve such issues in a way to promote the balance between the mutual interests by allowing such actions to continue. A solution to China's Three Gorges Dam dilemma based on a soft law approach is more credible than relying on a good faith approach of national responsibilities and international legal proceedings since the construction and operation of the dam falls within the category of exercising national sovereign rights. If a large scale construction project such as the Three Gorges Dam or operation of a nuclear power plant causes or may cause environmental damage beyond the border of a nation engaged in such an undertaking, countries affected by this undertaking should jointly monitor the environmental effects in a spirit of cooperation rather than trying to stop the construction and should seek cooperative solutions of mutual understanding to establish measures to prevent further damages. If China's Three Gorges Dam construction and operation cause or contain the possibility of causing serious damages to marine environment, China cannot set aside its national responsibility to meet international obligations if China is aware of or knows about the damage that has occurred or may occur but fail to prevent, minimize, reverse or eliminate additional chances of such damages, or fails to put in place measures in order to prevent the recurrence of such damages. However, Korea must be able to prove a causal relationship between the relevant actions and resulting damages if it is to raise objections to the construction or request certain damage-prevention actions against crucial adverse effects on the marine environment out of respect for China's right to develop resources and acts of use thereof. Therefore, it is essential to cumulate continuous monitoring and evaluations information pertaining to marine environmental changes and impacts or responses of affected waters as well as acquisition of scientific baseline data with observed changes in such baseline. As China has adopted a somewhat nonchalant attitude toward taking adequate actions to protect against marine pollution risks or adverse effects caused by the construction and operation of China's Three Gorges Dam, there is a need to persuade China to adopt a more active stance and become involved in the monitoring and co-investigation of the Yellow Sea in order to protect the marine environment. Moreover, there is a need to build a regular environmental monitoring system that includes the evaluation of environmental effects beyond borders. The Espoo Convention can serve as a mechanism to ease potential conflicts of national interest in the Northeast Asian waters where political and historical sensitivities are acute. Especially, the recent diplomatic policy advanced by Korea and China can be implemented as an important example of gentle cooperation as the policy tool of choice is based on regional cooperation or cooperation between different regions.

The Comparative Understanding between Red Ginseng and White Ginsengs, Processed Ginsengs (Panax ginseng C. A. Meyer) (홍삼과 백삼의 비교 고찰)

  • Nam, Ki-Yeul
    • Journal of Ginseng Research
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    • v.29 no.1
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    • pp.1-18
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    • 2005
  • Ginseng Radix, the root of Panax ginseng C. A. Meyer has been used in Eastern Asia for 2000 years as a tonic and restorative, promoting health and longevity. Two varieties are commercially available: white ginseng(Ginseng Radix Alba) is produced by air-drying the root, while red ginseng(Ginseng Radix Rubra) is produced by steaming the root followed by drying. These two varieties of different processing have somewhat differences by heat processing between them. During the heat processing for preparing red ginseng, it has been found to exhibit inactivation of catabolic enzymes, thereby preventing deterioration of ginseng quality and the increased antioxidant-like substances which inhibit lipid peroxide formation, and also good gastro-intestinal absorption by gelatinization of starch. Moreover, studies of changes in ginsenosides composition due to different processing of ginseng roots have been undertaken. The results obtained showed that red ginseng differ from white ginseng due to the lack of acidic malonyl-ginsenosides. The heating procedure in red ginseng was proved to degrade the thermally unstable malonyl-ginsenoside into corresponding netural ginsenosides. Also the steaming process of red ginseng causes degradation or transformation of neutral ginsenosides. Ginsenosides $Rh_2,\;Rh_4,\;Rs_3,\;Rs_4\;and\;Rg_5$, found only in red ginseng, have been known to be hydrolyzed products derived from original saponin by heat processing, responsible for inhibitory effects on the growth of cancer cells through the induction of apoptosis. 20(S)-ginsenoside $Rg_3$ was also formed in red ginseng and was shown to exhibit vasorelaxation properties, antimetastatic activities, and anti-platelet aggregation activity. Recently, steamed red ginseng at high temperature was shown to provide enhance the yield of ginsenosides $Rg_3\;and\;Rg_5$ characteristic of red ginseng Additionally, one of non-saponin constituents, panaxytriol, was found to be structually transformed from polyacetylenic alcohol(panaxydol) showing cytotoxicity during the preparation of red ginseng and also maltol, antioxidant maillard product, from maltose and arginyl-fructosyl-glucose, amino acid derivative, from arginine and maltose. In regard to the in vitro and in vivo comparative biological activities, red ginseng was reported to show more potent activities on the antioxidant effect, anticarcinogenic effect and ameliorative effect on blood circulation than those of white ginseng. In oriental medicine, the ability of red ginseng to supplement the vacancy(허) was known to be relatively stronger than that of white ginseng, but very few are known on its comparative clinical studies. Further investigation on the preclinical and clinical experiments are needed to show the differences of indications and efficacies between red and white ginsengs on the basis of oriental medicines.

The snacking pattern, diet, lifestyle and menu preferences of elementary school students in Gyeonggi area, considering the most frequently eaten snacks (자주 섭취하는 간식의 종류에 따른 경기지역 초등학교 고학년생의 간식섭취실태, 식생활과 생활습관 및 음식 기호도)

  • Park, Hyejin;Kang, Hyunjoo;Lee, Eun-Sook;Lee, Hongmie
    • Journal of Nutrition and Health
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    • v.54 no.5
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    • pp.547-559
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    • 2021
  • Purpose: This study compares the snacking pattern, diet, lifestyle, and food preference of children by evaluating the most frequently eaten snacks. Methods: The survey enrolled 435 students from three elementary schools in Gyeonggi. Based on the most frequently eaten snacks, the subjects were divided into 3 groups: fruits and milk/dairy products for natural snacks (NS, n = 114); noodles, snack foods and fast foods for meal-like snacks (MS, n = 74); cookies, beverages and bread as sweet snacks (SS, n = 247). Results: Compared to the MS group, preferences of the NS group were significantly higher for jabgokbap (cooked rice with multi-grains, p < 0.05) and saengchae (seasoned raw vegetables, p < 0.01), and significantly lower for gogitwigim (deep-fried meat, p < 0.05). Taste preference of the NS group was considered to be more desirable; the taste preference of more subjects was 'sweet taste' in the SS group, 'spicy taste' in the MS group, 'salty taste' in the MS and SS groups, and 'sour taste' and 'bland taste' in the NS group than the other groups. Compared to the MS and SS groups, the NS group was determined to exercise more frequently; exercising for more than 30 minutes/day was determined to be 76.3% in the NS group and 58.1% and 57.9% in the other groups (p < 0.01). Moreover, a higher proportion of subjects in the MS group tended to answer 'not hungry' as the reason for leaving school meals, as compared to other groups (p = 0.055), thereby suggesting that inappropriate snacking habits interfere with regular meals. Conclusion: This study provides evidence that healthy snacking habits, which include natural snacks such as milk/dairy products and fruits, are important for children during the elementary school years, since these habits are associated with healthier diet, lifestyle, and food and taste preferences. These results provide basic information for developing nutritional education materials for elementary school children.

Emotional Regulation's influence on Authentic Leadership and Change Oriented Organizational Citizenship Behavior (감성활용이 오센틱리더십과 변화적 조직시민행동에 미치는 영향)

  • Kang, Yoonhee;Kim, Jong Kwan
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.8 no.8
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    • pp.1-9
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    • 2018
  • Emotional Intelligence is the ability to recognize, facilitate, understand and control and utilize one's and other's emotions and has been researched extensively in last 20 years. Of the four domains of emotional intelligence, Emotional Regulation, the ability for one to manage and modify one's emotional reactions in order to achieve goal-directed outcomes, with its influence on authentic leadership and change oriented organizational citizenship behavior was researched by surveying 300 nurses at large metropolitan hospitals in B city in South Korea. Previous research demonstrated in relationship based and long term oriented cultures, such as Korea, Japan and Chinese cultures, ability to regulate emotions is critical component in successful social dynamics yet research the topic is minimal in Korea. Authentic leadership is a leader displaying sincerity and authentic behavior and through such, trust is gained in followers and collaboration is formed. Change oriented organizational citizenship behavior is a proactive behavior where the individual performs behaviors not included in his job functions voluntarily. The results indicate the three out of four sub domains of authentic leadership influenced positively to change oriented organizational citizenship behavior with the exception of balanced information processing. Moreover, Emotional Regulation partially mediated between authentic leadership and change oriented organizational citizenship behavior. Such results validated previous studies that indicated authentic leadership as possible antecedents of individual proactive behaviors and by examining authentic leadership and change oriented organizational citizenship behavior with emotional regulation as a mediator proved possibility as another potential antecedent of change oriented organizational citizenship behavior in hospital setting.

Age-related Changes in Luteinizing Hormone and Testosterone Levels in Korean Men (한국 남성의 혈중 Luteinizing Hormone과 Testosterone 수준의 연령-관련 변화)

  • Lee, Sung-Ho;Ahn, Ryun-Sup;Kwon, Hyuk-Bang
    • Development and Reproduction
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    • v.12 no.1
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    • pp.57-66
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    • 2008
  • Changes in luteinizing hormone (LH), serum testosterone (T), and salivary T levels with age were examined in Korean men. Serum was obtained from 167 Korean men of different ages ($20{\sim}69\;y$), and the serum LH and T levels were measured. Saliva samples were also obtained, and the salivary T level was determined. The LH levels did not change considerably until 40 y of age (20s, $2.5{\pm}1.0$; 30s, $2.7{\pm}1.5$; and 40s, $2.5{\pm}1.8\;mIU/mL$) but increased significantly around 50 y (50s, $3.7{\pm}1.8$ and 60s, $3.1{\pm}1.7\;mIU/mL$). Further, the serum T levels also did not change until 40 y of age (20s, $5.3{\pm}2.6$, 30s, $4.4{\pm}1.4$, 40s, $4.1{\pm}1.5\;ng/mL$) but decreased significantly at 50 y (50s, $3.4{\pm}1.5$; 60s, $2.6{\pm}0.8\;ng/mL$). The salivary T levels also showed small changes until the age of 40 y ($20s{\sim}40s$, $0.11{\pm}0.015\;ng/mL$) but decreased significantly at 50 y ($0.08{\pm}0.03\;ng/mL$). Thus, the relative ratio of salivary T to serum T levels did not change significantly in all the ages examined ($2.4{\pm}0.9%$). Linear regression analysis predicted that the LH levels increased 1.5%/y while the serum and salivary T levels decreased 1%/y and 0.8%/y, respectively. The serum T/LH ratio did not change considerably until the age of 40 y ($20s{\sim}40s$, $2.27{\pm}0.14$) but decreased significantly ($1.2{\pm}1.0$) at 50 y. Age-related changes in the salivary T/LH ratio were very similar to those in the serum T/LH ratio. These results demonstrated that LH and T levels in serum or saliva did not change considerably until 40 y of age; instead, in Korean men, from 50 y of age, the LH level increased, while the T level decreased. This suggests that primary testicular failure that occurred due to aging (approximately 50 y) and caused this phenomenon. The present study also shows that the salivary T level can be an indicator of the free T level in serum although the salivary T level correlates weakly with the total T level in serum (r=0.53). Thus, information regarding salivary T levels may be useful for studying the age-related changes occurring in male testicular physiology.

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