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Climatological Characteristics in the Variation of Soil temperature in Korea (우리나라 지중온도 변동의 기후학적 특성)

  • Kim Seoung-Ok;Suh Myoung-Seok;Kwak Chong-Heum
    • Journal of the Korean earth science society
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    • v.26 no.1
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    • pp.93-105
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    • 2005
  • Climatological characteristics in the variation of soil temperatures in Korea were investigated using Korea Meterological Administration's observation data. And the impacts of soil moisture on the variation of soil temperature were examined using observed precipitation data. The climatological averages of soil temperatures are ranged from 14.4 to $15.0^{\circ}C$ regardless of depths. And they showed an latitudinal gradient with a warm temperature at the southern region and 'U' shape as in the air temperature with a high value along the coastal region. The relatively higher heat capacity and low conductivity of soil compared to those of the air resulted in the significant delay of the maximum and minimum date with depth. As a results, soil acts as a heat source during winter while a heat sink during summer. Global warming and urban heat island have increased the soil temperatures with an average rate $0.3\~0.5^{\circ}C/10-year$ as in the air temperature during last 30 years $(1973\~2002)$. However, the warming rate is maximized during spring contrary to the winter in the air temperature. The temporal variation of soil temperatures is strongly affected by that of soil moisture through an modification of the heat capacity and heat convection. In general, the increased soil moisture clearly decreased the temporal variations and increased the deep layer soil temperatures during cold season.

Development and Adult Life Span of Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae) Fed on the Melon Aphid, Aphis gossypii Glover or the Green Peach Aphid, Myzus persicae($S\"{u}lzer$) (Homoptera: Aphididae) (목화진딧물(Aphis gossypii)과 복숭아혹진딧물(Myzus persicae) (Homoptera: Aphididae)을 먹이로 한 진디혹파리[Aphidoletes aphidimyza (Rondani)] (Diptera: Cecidomyiidae)의 발육 및 성충수명)

  • Kim Tae-Heung;Kim Ji-Soo
    • Korean journal of applied entomology
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    • v.43 no.4 s.137
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    • pp.297-304
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    • 2004
  • The development of Aphidoletes aphidimyza, an aphidophagous gall midge, was studied at various constant temperatures ranging from 15 to $35^{\circ}C$, with $65{\pm}5\%$ RH, and a photo-period of 16L:8D. When A. aphidimyra was fed either on Aphis gossypii or Myzus persicae, it took 43.9 and 44.5 days, respectively, to develop from egg to pupa at $15^{\circ}C$, whereas at $25^{\circ}C$, 14.3 and 15.8 days. The developmental zero was 10.7 and $10.0^{\circ}C$, respectively, while the effective accumuative temperatures were 210.8 and 245.5 day-degrees. The nonlinear shape of temperature-dependent development, shown by A. aphidimyza when fed on either species of the aphids, was well described by the modified Sharpe and DeMichele model. When distribution model of completion time of development for each growth stage was expressed as physiological age and fitted to the Weibull fuction, the completion time of development gradually shortened from egg to larva, and to pupa. In addition, the coefficient of determination $r^2$ ranged between 0.86-0.93 and 0.85-0.94, respectively providing a good approximation of cumulative developmental rates. The life span of adult was 8.7 and 9.2 days at $15^{\circ}C$, and 3.1 and 2.7 days at $30^{\circ}C$, respectively. Egg incubation period was relatively short at $35^{\circ}C$ but hatchability was less than $50\%$ and the mortality of the larva at $35^{\circ}C$ reached $100\%$. At $30^{\circ}C$, the time of development lengthened and the adult longevity was short suggesting ill effect of high temperatures. Even though the life span of adults at $15^{\circ}C$ was relatively long, none moved freely in the rearing cage and no oviposition occurred. Accordingly, in case A. aphidimyza is adopted to suppress phytophagus aphid populations, it could be applicable to cropping systems with ambient temperatures above $20^{\circ}C$ and below $30^{\circ}C$. Within this range, A. aphidimyza adults was observed to be active and oviposit fully.

A study of the effects of PDGF-BB on the characteristics of bone stromal and periodontal ligament cells (혈소판유래성장인자-BB가 골간질세포와 치주인대세포의 성상에 미치는 영향)

  • Kwon, Young-Hyuk;Park, Joon-Bong
    • Journal of Periodontal and Implant Science
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    • v.26 no.4
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    • pp.949-965
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    • 1996
  • The main goal of periodontal therapy is to restore the lost periodontal tissue and establish the attachment appratus. Current acceptable therapeutic techniques are included : removal of diseased soft tissue, demineralization of exposed root surface, using the barrier membrane for preventing the downgrowth of gingival epithelial cell, insertion of graft materials as a scaffolding action, and biological mediators for promoting the cell activity. The latest concept one among them has been studied which based on the knowledge of cellular biology of destructed tissue. Platelet-derived growth factor(PDGF) is one of the polypeptide growth factor which have been reported as a biological mediator to regulate activities of wound healing progress including cell proliferation, migration, and metabolism. The purposes of this study is to evaluate the influences of the PDGF as biological mediator to periodontal ligament and bone marrow cell. Both right and left maxillary first molar were extracted from rat which had treated with 0.4% ${\beta}-Aminopropionitril$ for 5 days, and feeded until designed date to sacrifice under anesthesisa. Periodontal ligament were removed from the extracted socket of the rat, and cultured with Dulbecco's Modified Essential Medium(DMEM) contained with 10% Fetal Bovine Serum, 100U/ml penicillin, $100{\mu}g/ml$ streptomycin, $0.5{\mu}g/ml$ amphotericin-B. Bone marrow cell were culture from bone marrow suspension with which washed out from femur with same medium. The study was performed to evaluate the effect of PDGF to periodontal ligament and bone cell, cell proliferation rate, total protein synthesis, and alkaline phosphatase activity of rat periodontal ligament(PDL) cell and bone stromal(RBS) cell in vitro. The effects of growth factors on both cells were measured at 3, 5th day after cell culture with (control group) or without growth factors(experimental group). The results were as follows: 1. The tendency of cell proliferation under the influence of PDGF showed more rapid proliferation pattern than control at 3 and 5 days after inoculation. 2. The activity of Alkaline phosphatase revealed 14, 80% increased respectively at 3, 5 days culture than control group. Measurements of ALPase levels indicated that PDL cells had significantly higher activity when compared with that of co-culture groups and GF only(P<0.05). And, ALPase activity in 10 days was higher than that of 7 days(P<0.05). 3. The tendency of formation of the mineralized nodule were observed dose-depend pattern of PDL cells. There was statistically significant difference among group l(PDL 100%), 2(PDL 70%:GF 30%), and 3(PDL 50%:GF 50%)(P<0.01). But, there was no difference among group 3, 4(PDL 30%:GF 70%), and 5(GF 100%). 4. Also, the number of nodule was greater in co-culture of PDL 70% and GF 30% than in culture of PDL 70%(P<0.05). From the above results, it is assumed that the PDGF on PDL cells and RMB cell culture. GF stimulates the cell growth, which is not that of PDL cells but GF. And, the activity of ALPase depends on the ratio of PDL cells, and ALPase may relate to the initial phase of nodule formation. Also, it is thought that the calcified nodule formation principally depends on PDL cells, is inhibited by GF, and affected by cell density. In conclusion, platelet-derived growth factor can promote rapid osteogenesis during early stage of periodontal tissue regeneration.

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A Study on the Interpretation of Cultural Heritage Sites for Public Education (대중교육을 위한 문화유적의 해석(Interpretation)에 관한 기본연구)

  • Han, Sang-U
    • KOMUNHWA
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    • no.68
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    • pp.41-57
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    • 2006
  • The purpose of this study is to review educational value of cultural heritage sites first and then, to examine the importance of interpretation and interpretation methods and process briefly to utilize cultural heritage sites as important resources for public education and cultural tourism. The educational value of cultural heritage sites is not limited to provide visitors with various information on historical facts and events related to the cultural heritage site, but to provide the public with a new recognition of the importance of the preservation of cultural heritage sites by understanding the site well. In order to utilize the educational value of the cultural heritage site, interpretation must be emphasized as an important element of cultural heritage sites management and much attention should be given on the development and practice of interpretation programs in each cultural heritage site. In order to develop an interpretation program of the site, a specific target audience must be defined first to find most resonable scope and direction of an interpretation program and then, site specific interpretation themes (or a theme) should be developed from the interpretive topic. According to these defined elements, an interpretation program(s) is established by using various interpretation methods and techniques in order to provide visitors with useful information and knowledge on the site efficiently. Interpretation methods and techniques are various as defined by various ways and most effective methods or techniques are employed as a specific interpretation program is presented most effectively. The evaluation processes in planing stage, during developing stage, and after completion of interpretation program development are important processes to find out any problems of planed interpretation program and to revise or update the interpretation program. Conclusively, the direction of cultural heritage sites management in Korea has focused on the conservation and restoration of cultural heritage sites to preserve the original conditions of cultural heritage sites so far. This direction on current practice on cultural heritage sites management should he changed to more active utilization of the sites and interpretation of the sites is a way to accomplish the this goal.

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Fluorine-releasing of Dental Restoration Materials in which the Fluorine is Contained (불소 유리로 본 불소 함유 수복재)

  • Kim, Joo-Won
    • The Journal of the Korea Contents Association
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    • v.12 no.5
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    • pp.311-322
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    • 2012
  • Restoration materials used to investigate effects of fluorine such as enamel strengthening and anti-caries effects in several types of dental restoration materials were five kinds including Ionoseal(VOCO GmbH, Cuxhaven, Germany), Fuji Filling LC(GC Co. Tokyo, Japan), Quadrant Universal LC(CAVEX Holland BV, Netherlands), PermaCem$^{(R)}$(DMG, Hamburg, Germany) and Dyract$^{(R)}$ AP(Dentsply GmbH, Germany), and the amount of fluorine-releasing was measured with ICS-5000 Reagent-FreeTM Ion Chromatography(RFICTM, Dionex, U.S.A.). The results of this study are as follows. 1. In all types of restoration materials, the amount of fluoride-releasing was reduced with time passage and it was declined sharply to show significance in four weeks. Fuji Filling LC(12.445PPM) or resin-reinforced glass ionomer and PermaCem$^{(R)}$(16.121PPM) or compomer were found to release fluorine for a long term(P<.001). 2. Ionoseal(0.887PPM) or glass ionomer and Quadrant Universal LC(0.957PPM) or composite resin released a few fluorine of 1PPM or less than 1PPM after one week, and Dyract$^{(R)}$ AP or compomer released fluorine of 8.631PPM in one week and its amount of releasing decreased dramatically in two and four week by recording 0.175PPM and 0.116PPM, respectively. Therefore, the effect of releasing fluorine in four weeks was observed to be poor (P<.001). 3. Fuji Filling LC or resin-reinforced glass ionomer and PermaCem$^{(R)}$ or compomer released fluorine of 33.372 and 1.902PPM, respectively in one week and their amount of releasing increased to be 36.371 and 18.223PPM, respectively in two weeks. So, their amount of fluorine-releasing recorded the highest levels in two weeks(P<.001).

Diagnostic Accuracy of PET and MR for Detecting Liver Metastasis from Colorectal Cancer (대장-직장암의 간전이에서 FDG PET과 MR의 진단 성능)

  • Park, Eun-Kyung;Kang, Won-Jun;Eo, Jae-Seon;Lee, Dong-Soo;Chung, June-Key;Lee, Myung-Chul
    • Nuclear Medicine and Molecular Imaging
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    • v.40 no.5
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    • pp.249-256
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    • 2006
  • Purpose: Although computed tomography (CT) is widely used for diagnosing liver metastasis from colorectal cancer, diagnostic accuracy of CT is not satisfactory. Magnetic resonance (MR) imaging and F-18 FDG PET has been reported to be superior to CT. However, studies on direct comparison of PET and MR are scarce. We compared the diagnostic accuracy of FDG PET and MR in detecting liver metastasis from colorectal cancer. Materials and Methods: Among 363 colorectal cancer patients who underwent F-18 FDG PET (ECAT, Siemens-CTI, Knoxville; Gemini, Philips, Milpitas, U.S.), 26 patients (M:F=17:9, age=$62{\pm}11$) underwent MR to evaluate suspicious metastatic liver lesions. Finally, 35 liver lesions detected by CT from 26 patients were enrolled for analysis. PET and MR results were compared with pathologic reports, clinical findings or follow-up results. Results: Of the 35 lesions, 18 lesions (51.4%) were diagnosed as liver metastases, while remaining 17 (48.6%) as benign. The sensitivity and the specificity of PET were 94.4% and 94.1%, respectively, compared to 100% and 82.4% for MR. MR and PET was concordant in 30 lesions (85.7%: 17 metastatic (94.4%) and 13 benign (76.5%) lesions. ROC curve analysis revealed maximal SUV of 3.1 as the optimum standard in differentiating metastatic from benign liver lesions (AUC=0.897, p<0.001, sensitivity 83.3%, specificity 94.1%). For small lesions less than 1 cm ln diameter (n=20), diagnostic accuracy of PET was comparable to that of MR. Conclusion: F-18 FDG PET showed good diagnostic performance in detecting liver metastasis from colorectal cancer, which was comparable to MR.

An Evaluation on Health Conditions of Pyong-Chang River using the Index of Biological Integrity (IBI) and Qualitative Habitat Evaluation Index(QHEI) (생물보전지수(Index of Biological Integrity) 및 서식지 평가지수 (Qualitative Habitat Evaluation Index)를 이용한 평창강의 수환경 평가)

  • Jung, Seung-Hyun;Choi, Shin-Sok;An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.34 no.3 s.95
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    • pp.153-165
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    • 2001
  • We evaluated the health condition of Pyong-Chang river, the tributary of Han- River, using the Index of Biological Integrity (IBI) and Qualitative Habitat Evaluation Index (QHEI) during September 1999${\sim}$August 2000. The annual mean of IBI, which was estimated using eleven metrics, was 49 (range: $45{\sim}51$) and the mean of QHEI, which was estimated using seven parameters, was 88 (range: $76{\sim}94$) during the study. The river health, based on the IBI criteria of Karr (1981), ranged from "excellent" to "good" conditions, while based on the habitat criteria of Plafkin et al. (1989), it ranged from "pristine" (comparable to reference) to "supporting" conditions. Values of IBI showed slight differences between upstream and downstream sites and QHEI values varied weakly depending on characteristics of variables. Regression analyses showed that annual values of QHEI had no functional relations with stream order (p = 1.82; n = 8) but showed some decreases near slight point-sources. This result indicates that conditions of physical habitat did not change highly with increases of the stream order. According to analyses of feed guilds, relative abundance of insectivores, omnivores and carnivores was 85.1%, 3.5% 0.3%, respectively. Also, relative abundance of sensitive and tolerant species was 75% and 4.6%, respectively, while exotic and morphological anomalies were not found in the river. These outcomes indicate that health condition of fish, based on the trophic conditions of U.S. EPA (1993), was excellent in the river. Regression analyses of IBI values against the QHEI showed that the variation of habitat conditions accounted 57% for the variation of the Index of Biological Integrity (p<0.05; $R^2\;=\;0.57$; n = 7).Overall data of IBI and QHEI suggest that the river health in the present is in optimal conditions but may be degradated by acceleration of chemical inputs and physical-habitat disturbance.

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Molecular identification and Phylogenetic relationship of the rook (Corvus frugilegus) population in Jeju-do Province, South Korea (제주도에 도래하는 떼까마귀 집단에 대한 분자 종 동정 및 계통 유연관계)

  • Han, Sang-Hyun;Kim, Tae-Wook;Kim, Yoo-Kyung;Park, Jun-Ho;Kim, Dong-Min;Adhikari, Preadeep;Park, Su-Gon;Park, Seon-Mi;Kim, Ga-Ram;Lee, Jun-Won;Oh, Hong-Shik
    • Korean Journal of Environment and Ecology
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    • v.29 no.5
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    • pp.693-702
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    • 2015
  • In order to identify the species and to reveal the phylogenetic relationship of rook populations found in Jeju-do Province in winter seasons, we determined the sequences of mitochondrial cytochrome c oxidase I (COI) gene and analyzed the genetic structure of maternal lineages and phylogenetic relationship. The rook DNAs were isolated from the post-mortem specimens and plumages collected from agricultural farms in Jeju-do Province including U-do Island. The obtained COI sequences (n=41) showed over 97.0% identities with those previously reported from Corvus frugeligus. Three COI haplotypes (J01-J03) were detected from COI sequences of the rooks obtained in Jeju-do Province but those did not show the site-specific patterns, showing that they might be derived from a common maternal origin. Eight maternal haplotypes were detected from all COI sequences obtained. Among those three haplotypes contained the COI sequences from Northeast Asia including eastern Russia, Mongolia and South Korea. On the other hand, the other five haplotypes contained the COI sequences reported from Central Asia, Middle East, western Russia and European countries. The COI sequences from Jeju-do Province were located on three haplotypes (CF01-CF03) belonging to Northeast Asian rook lineages. The NJ tree showed the distinct branch patterns suggesting two different maternal lineages of C. frugilegus, which proposed as two parapatric subspecies, C. f. frugilegus (Western) and C. f. pastinator (Eastern). These findings using DNA barcoding approaches will be contributed to provide the information about avian fauna for understanding the genetic structure of maternal lineage, phylogenetic relationship and their molecular ecology.

Ecological Characteristics of Rhodotypos scandens Habitat in Imsil-gun, Jeollabuk-do, Korea (전라북도 임실군 병아리꽃나무 자생지의 생태적 특성)

  • Park, Kyung-Uk;Beon, Mu-Sup;Oh, Hyun-Kyung;You, Ju-Han
    • Journal of Environmental Impact Assessment
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    • v.24 no.4
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    • pp.352-366
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    • 2015
  • The purpose of this study is to offer the basic data to the habitat conservation and management by surveying and analysing the ecological characteristics such as the flora, vegetation structure and soil of Rhodotypos scandens habitat. The flora were summarized as 131 taxa including 57 families, 99 genera, 107 species, 1 subspecies, 17 varieties and 6 forms. The life forms grouped as in the follows; the megaphanerophytes(MM) were 21 taxa, 24 taxa of the microphanerophytes(M), 30 taxa of nanophanerophytes(N), 6 taxa of chamaiphytes(Ch), 20 taxa of hemicryptophytes(H), 17 taxa of geophytes(G), 12 taxa of therophytes(Th) and 1 taxa of hydrophytes(HH). The present conditions of communities were 8 types including Zelkova serrata, Quercus aliena, Ulmus parvifolia, Rhamnella frangulioides, Castanea crenata, Albizia julibrissin, Celtis sinensis and Robinia pseudoacacia. In case of the dominant species by layers, the tree layer species were Zelkova serrata, Quercus aliena, Ulmus parvifolia, Castanea crenata, Albizia julibrissin, Celtis sinensis and Robinia pseudoacacia, and the subtree layer species were Rhamnella frangulioides, Q. aliena, Z. serrata, A. julibrissin, U. parvifolia and Broussonetia kazinoki. The shrub layer species was Rhodotypos scandens. In the results of analyzing the diversity index, $H^{\prime}{_{max}}$ from 1.691 to 2.610, from 2.197 to 3.466 in H'max, from 0.646 to 0.903 in J' and from 0.097 to 0.354 in D. In the results of analysing the soil, there showed that acidity was 5.6, 0.5dS/m of electrical conductivity(EC), 59.1mg/kg of available $P_2O_5$, 49.7% of organic matter content, $0.4cmol^+/kg$ of exchangeable $K^+$, $13.5cmol^+/kg$ of exchangeable $Ca^{2+}$, $3.3cmol^+/kg$ of exchangeable $Mg^{2+}$.

Screening of Antiviral Activities of Korean Medicinal Herbs and Traditional Prescriptions Against Herpes Simplex Virus Type-1 (한약단미제 및 탕제의 항 Herpes Simplex Virus Type-1 활성탐색)

  • Kang, Bong-Joo;Yang, Ki-Sang;Kim, Myung-Hee;Park, Kap-Joo
    • The Journal of Korean Society of Virology
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    • v.27 no.2
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    • pp.227-237
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    • 1997
  • In order to search for anti-Herpes simplex virus (HSV) type-1 agents from Korean medicinal herbs and Korean traditional prescriptions (herb complexes), we selected 80 medicinal herbs and 45 prescriptions, based on a review of the Korean traditional medicine books. Both methanol extracts and boiling-water extracts were tested by means of the MTT assay (tetrazolium based colorimetric assay). Ten of the 125 methanol extracts: CM-11, CM-18, CM-19, CM-21, CM-22, CM-39, MM-3, MM-18, MM-29, MM-73 (see explanation of nomenclature below), showed efficacy against HSV-1. Twelve of the water extracts: CW-2, CW-3-I, CW-3-II, CW-18, MW-3, MW-5 MW-6, MW-12, MW-47, MW-69, MW-73 and MW-79 were active. #3 (individual herb) and #73 (individual herb) were interesting because both water and methanol extracts were active. Especially, #3 is a part of composition of Hong-il-$laksamd{\check{u}}ngbang$ and Hojanghaedokt'ang which have anti-HSV-1 activitives. The SI value of MW-69 and CW-18 was relative high as $10.2{\pm}0.7$ and $11.8{\pm}2.2$. The cytotoxic effect on Vera cells of $Panch'{\check{o}}nch'onch'{\check{o}}ngbang$, Taraxacum platycarpum H. Dahlst. and acycloguanosine was determined by MTT assay. Water extracts of $Panch'{\check{o}}nch'onch'{\check{o}}ngbang$ (prescription) and Taraxacum platycarpum H. Dahlst. showed very weak cytotoxic effects on Vero cells at > $100\;{\mu}g/ml$ but acycloguanosine showed strang cytotoxic effects on Vera cells at > $100\;{\mu}g/ml$. As a result, #3, #73, MW-69 and CW-18 are considered as potentially useful for anti-HSV-1 agent and will be the focus of further research. Abbreviations: CM - methanol extracts of traditional prescriptions; CW - water extracts of traditional prescriptions; MM - methanol extracts of individual herbs; MW - water extracts of individual herbs.

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