• Journal of the Korean Society of Radiology
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• v.82 no.6
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• pp.1505-1523
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• 2021

Purpose Although chest CT has been discussed as a first-line test for coronavirus disease 2019 (COVID-19), little research has explored the implications of CT exposure in the population. To review chest CT protocols and radiation doses in COVID-19 publications and explore the number needed to diagnose (NND) and the number needed to predict (NNP) if CT is used as a first-line test. Materials and Methods We searched nine highly cited radiology journals to identify studies discussing the CT-based diagnosis of COVID-19 pneumonia. Study-level information on the CT protocol and radiation dose was collected, and the doses were compared with each national diagnostic reference level (DRL). The NND and NNP, which depends on the test positive rate (TPR), were calculated, given a CT sensitivity of 94% (95% confidence interval [CI]: 91%-96%) and specificity of 37% (95% CI: 26%-50%), and applied to the early outbreak in Wuhan, New York, and Italy. Results From 86 studies, the CT protocol and radiation dose were reported in 81 (94.2%) and 17 studies (19.8%), respectively. Low-dose chest CT was used more than twice as often as standard-dose chest CT (39.5% vs.18.6%), while the remaining studies (44.2%) did not provide relevant information. The radiation doses were lower than the national DRLs in 15 of the 17 studies (88.2%) that reported doses. The NND was 3.2 scans (95% CI: 2.2-6.0). The NNPs at TPRs of 50%, 25%, 10%, and 5% were 2.2, 3.6, 8.0, 15.5 scans, respectively. In Wuhan, 35418 (TPR, 58%; 95% CI: 27710-56755) to 44840 (TPR, 38%; 95% CI: 35161-68164) individuals were estimated to have undergone CT examinations to diagnose 17365 patients. During the early surge in New York and Italy, daily NNDs changed up to 5.4 and 10.9 times, respectively, within 10 weeks. Conclusion Low-dose CT protocols were described in less than half of COVID-19 publications, and radiation doses were frequently lacking. The number of populations involved in a first-line diagnostic CT test could vary dynamically according to daily TPR; therefore, caution is required in future planning.

• Parasites, Hosts and Diseases
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• v.28 no.2
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• pp.109-114
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• 1990

Status of intestinal protozoan and helminthic infections was surveyed in mestizo population living in rural parish of Palmar and its nearby recintos(villages) , Three of the surveyed villages were at the Pacific coast and 5 villages were in inner pasture land, located about 100 km west of Guayaquil, the second largest city in Ecuador. One stool sample was examined by one cellophane thick smear for helminth ova and one direct smear stained with Lugol's iodine solution for protozoan cysts. Of 325 persons examined, 66.1% were positive for any ova or cyst. The positive rates were: 18.1% for Ascaris lumbricoides, 19.4% for Trichuris trichiura, 0.6% for hookworm, 3.7% for Hyntenolepis nana, 1.8% for Taenia sp., 19.4% for Entnmoeba histolytica, 28.6% for Entamoeba coli, 5.5% for Endolimax nasa, 1.5% for ledamoeba buetschlii, 11.l% for eiardia lamblia and 0.6% for Chilomastix mesnili. Poor supply of potable water was considered the main cause of high prevalence of intestinal protozoan infections.

• Clinical and Experimental Pediatrics
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• v.50 no.3
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• pp.262-267
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• 2007

Purpose : The prevalence of hepatitis A virus (HAV) in a certain community reflects that community's living standards and hygienic conditions. And the pattern of HAV infection differs over time and geography. Recently, a shift in prevalence has been observed in cases from chilhood to adulthood. We studied the HAV antibody prevalence in the general population in Busan. Methods : From October 2004 to March 2005, total 472 subjects were tested for HAV antibodies. All samples were collected from patients in Maryknol Hospital. Results : The overall seropositive rate was 22.8% (108/472). The seropositive rates were 1.7% in subjects aged 2-5 years, 1.7% in 6-10 years, 0% in 11-20 years, 40.5% in 21-30 years, 82.1% in 31-40 years, 94.7% in 41-50 years, and 100% in subjects aged over 50 years. There was no significant gap between gender groups. Conclusion : As the socioeconomic conditions in Korea have improved, the HAV seropositive rate in school-aged children has dramatically decreased in the last 20 years. But, the seropositive rate of HAV didn't differ according to gender. The seropositive rate of HAV in the pediatric group was very low, which suggests the increasing possibility of clinical HAV infection in adults in the near future. Therefore, we should actively prevent the spread of hepatits A virus. In order to do that, we need to reorganize our lifestyle and personel hygiene and carry out active and passive immunization to high risk groups.

• Korean Journal of Poultry Science
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• v.39 no.2
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• pp.97-104
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• 2012

Newcastle disease virus (NDV) infects a variety of birds with a wide range of clinical signs from asymptomatic to severe. During a 10-month period in 2011, a total of 1,024 sera from wild birds including 42 species of birds in 8 orders were collected and the seroprevalence of NDV in wild birds was evaluated by hemagglutination inhibition (HI) test. Evidence of NDV infection was observed in 12.6% (129/1,024) of wild birds with a maximum prevalence reported in Mandarin duck (27.8%, 32/115) followed by Mallard duck (20.8%, 57/274), Spot-billed duck (11.9%, 36/303), Pintail (2.9%, 1/34), Black-tailed gull (2.9%, 1/34), White-fronted goose (1.8%, 1/56) and Common teal (1.4%, 1/69). None of the other 35 species of wild birds were antibody-positive for NDV. Mandarin duck, Mallard duck and Spot-billed duck showed high sero-prevalance of 12.2% to 42% during winter season (November to March). Our results indicate that Mandarin duck, Mallard duck and Spot-billed duck might be natural reservoirs for NDV in Korea and the prevalence of NDV infection in wild birds displayed a seasonal pattern with high prevalence of NDV in winter season (November to March).

• Parasites, Hosts and Diseases
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• v.29 no.2
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• pp.101-112
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• 1991

While various examples of rationale or benefits of ascariasis control could justify a necessity of control activity in a community, few practical index other than the e99 Prevalence or intensity of infection has been used to evaluate the efficacy obtained by the control activity. A literature-based retrospective study was undertaken to provide some numerical data on the decreasing morbidity of surgical ascariasis as a consequence of ascariasis control in Korea. A thorough review of literatures (1959∼1990) on biliary and other surgical complications of ascariasis reported from general hospitals revealed that their incidence has been decreasing very proportionally to the national figures of its e99 Prevalence and worm burden. For example, according to the remarkable decreases of the prevalence of ascariasis, there is an evident decreasing tendency of the proportion(%) of ciliary ascariasis cases among all biliary surgical patients and the proportion of biliary ascariasis cases among all biliary stone patients in general hospitals. It is highly suggested that the Korean people have been much benefited by the control activity of ascariasis executed at a national scale since 1960s, especially in terms of incidence of biliary and other surgical complications of ascariasis.

• Parasites, Hosts and Diseases
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• v.23 no.1
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• pp.18-23
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• 1985

The infection stasus of the loaches, Misgurnus anguillicaudatus, with the metacercariae of Echinostoma hortense, was studied in Korea. A total of 154 loaches purchased at 4 local markets (Seoul, Kimhae, Naju-gun and Kangjin-gun) were examined their infection rate as well as the density and location of the metacercariae in the fish body. The results are as follows: 1. The loaches carrying the metacerariae of E. hortense were 64 (41.6%) in total number and the metacercarial density ranged 1-29 per infected loach with an average value of 8.1. The highest infection rate and metacercarial density were obtained from the loaches purchased at Kangjin-gun, Jeonranam-do. 2. The metacercariae of E. hortense were chiefly distributed in the distal intestinal wall and the adjacent mesentery, the perianal tissues, and the head and gill of the loaches examined. From the results, it is concluded that the loach is one of the important second intermediate hosts of E. hortense in Korea, and their infection rate and metacercarial density are considerably high.

• Journal of Naturopathy
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• v.11 no.2
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• pp.136-142
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• 2022

Background: We are necessarily considering changes in the parasite infection rate and methods in Korea from 1970 to the present from the perspective of natural healing. Purposes: This study was to investigate how the difference in the rate of reduction in infection rate has changed and progressed to the present. Methods: A literature review was conducted. Results: Until the 1970s, Korea had one of the highest parasite infection rates. The Parasitic Disease Prevention Act was enacted to control the infection rate in 1966. From 1969, the nationwide national parasite management project was conducted for all students twice a year to treat all parasitic eggs until 1995. In addition, the government commissioned the Korean Association for Parasite Eradication (KAPE) to conduct a national parasite infection survey eight times, from 1971 to 2012, every two years. As a result, the overall egg positive rate of parasite was 84.3% in 1971 but decreased to 2.6% in 2012. In addition, Ascaris lumbricoides, Paragonimus westermani, Taenia spp., and intestinal protozoa were significantly reduced nationwide. Conclusions: Successful control in Korea is judged to have achieved a successful effect by systematically managing national economic growth, social consensus on parasite eradication, improved professional parasite prevention guidelines, and supply of effective anthelminthics.

• Journal of environmental and Sanitary engineering
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• v.1 no.1 s.1
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• pp.69-79
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• 1986

This studies were carried out to investigate the high infection sites from various specimens, cultural isolation on the susceptible media and specific antibody titres of M. pulmonis in experimental 310 mice and 330 rats obtained from two breeding facilities. Efficiency of complement faxation test (CF test) for detection of M. pulmonis antibody in mice and rats were compared directly with the diagnostic cultural isolation method. 1. Isolation rates of M. pulmonis among infection sites were about 30% from the oral cavities and $40\%$ from the middle ear of mice. The rates were $100\%$from the nasal cavaties and $90\%$ from the oral cavities of rats. 2. The infection rates were $12\%$ to A group and $16\%$ to B group of mice. The rates in the rats were $55\%$ to A group and $70\%$ to B group. 3. The M. pulmonis antibody titres by CF test were $73\%$ of total 100 mice in serum dilution below 1:5 (< 1:5), and $24\%$ of total samples in antibody titres above 1:5 (> 1:5), but 3 samples were not showed anticomplementary activities. The antibody titres in rats were $35\%$ of 120 rats in below 1:5 (< 1:5), and $61\%$ of total samples in above 1:5 (> 1:5), but the remained were not showed anticomplementary activities.

• Journal of radiological science and technology
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• v.34 no.4
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• pp.333-339
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• 2011

The purpose of this study is to compare DNA repair characteristics of normal fibroblast cell (MRC-5) and neuroblastoma cell (SK-N-SH) induced by proton beam. Cells were irradiated with 2Gy, 5Gy and 8Gy proton beam. The rate of DNA rejoining was measured by alkaline version of the comet assay. After a repair time, tail moment was measured again. The tail moment of MRC-5 was lower than SK-N-SH. However, after 8Gy of exposure, the tail moment of MRC-5 was measured as 50.320223.17155 which represents dangerous level of DNA damage. The cells were repaired practically within 25 hours after 2 and 5Gy of exposure while they were not fully recovered after 8Gy of exposure. Especially, tail moment of MRC-5 after 25 hours was 18.15364.42849. In the distal declining edge of SOBP, the RBE value is increased by high LET. The RBE differences of SOBP in high-dose were greater than low-dose. After the high-dose exposure, MRC-5 of normal fibroblast cell could lead to lasting DNA damage as shown in this study. In conclusion, we has to pay special attention when the region of the treatment volume is close to sensitive tissues.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.2
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• pp.155-163
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• 2019

During the time period from 2010 to 2017, out of 162,551 blood specimens, 11,233 (6.9%) specimens were positive for culture and 11,865 strains were cultured. Among the isolates, 47.8% were Gram positive cocci, 38.8% were Gram negative rods, 4.2% were Gram positive bacilli, 6.8% were fungi and 2.3% were anaerobes. When the culture results were compared according to gender, 55.0% (2,732/4,969) of the isolates were found in males and 45.0% (2,237/4,969) were isolated in females. In addition, when categorized according to age group, people in their 70s were the most separated by 28.7% (1,426/4,969) and this showed a great difference from 1.2% (62/4,969) of people in their teens. MRSA decreased significantly from 66.7% in 2016 to 46.8% in 2017. The vancomycin resistance rate of E. faecium was 35.0% (48/137). The ESBL positive rate of E. coli in intestinal bacteria was increased from 17.2% in 2010 to 28.8% in 2017, but the positive rate decreased for K. pneumoniae. 11.8% (14/119) of multidrug-resistant P. aeruginosa (MDRPA) of P. aeruginosa and 64.3% (161/252) of MDRAB of A. baumannii showed high resistance. Because the microbial susceptibility and antimicrobial susceptibility patterns of the blood specimens isolated from all the blood specimens differ according to the time period, region and patients, periodic analyses of different pathogens and understanding the changes in the degree of susceptibility to antimicrobial susceptibility have been conducted in hospitals.