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        검색결과 24

        3.
        2021.02 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        We study galaxies undergoing ram pressure stripping in the Virgo cluster to examine whether we can identify any discernible trend in their star formation activity. We fi rst use 48 galaxies undergoing different stages of stripping based on Hi morphology, Hi de ficiency, and relative extent to the stellar disk, from the VIVA survey. We then employ a new scheme for galaxy classi fication which combines Hi mass fractions and locations in projected phase space, resulting in a new sample of 365 galaxies. We utilize a variety of star formation tracers, which include g - r, WISE [3.4]-[12] colors, and starburstiness that are de fined by stellar mass and star formation rates to compare the star formation activity of galaxies at different stripping stages. We find no clear evidence for enhancement in the integrated star formation activity of galaxies undergoing early to active stripping. We are instead able to capture the overall quenching of star formation activity with increasing degree of ram pressure stripping, in agreement with previous studies. Our results suggest that if there is any ram pressure stripping induced enhancement, it is at best locally modest, and galaxies undergoing enhancement make up a small fraction of the total sample. Our results also indicate that it is possible to trace galaxies at different stages of stripping with the combination of Hi gas content and location in projected phase space, which can be extended to other galaxy clusters that lack high-resolution Hi imaging.
        5,400원
        4.
        2016.04 구독 인증기관·개인회원 무료
        Human body and head lice are obligatory human ectoparasites. Although both body and head lice belong to a single species, Pediculus humanus, only body lice are known to be a vector of several bacterial diseases. The higher vector competence of body lice is assumed to be due to their weaker immune response than that of head lice. To test this hypothesis, immune reactions were compared between body and head lice following infections by two model bacteria, Staphylococcus aureus and Escherichia coli, and a human pathogen, Bartonella quintana. Following dermal or oral challenge, the number of these bacteria increased both in hemocoel and alimentary tract of body lice but not in head lice and the viability of the B. quintana was significantly higher in body louse feces, the major route of infection to human. In addition, body lice showed the lower basal/induced transcription level of major immune genes, cytotoxic reactive oxygen species and phagocytosis activity compared with head lice. These findings suggest that a reduced immune response may be responsible, in part, for the increased proliferation and excretion of viable bacteria which are associated with the high level of human infectivity seen in body versus head lice.
        5.
        2007.04 KCI 등재 구독 인증기관·개인회원 무료
        Amelobl astic carcinoma(AC) is a maJignant coun terpart of ameloblastoma. histologically characteri zed by amelobJastomatolls feature with obviollS cytologic a typi a . AC is a r are malignant tumor with poten t iaJ of metastasis‘ asssllmed to occur far less tha n 1% of ameloblastoma . Nearly 80% of ACs have been reported to occur in the mandibJ e. The allthors reviewed 5 cases of AC in Department of Oral PathoJogy. SeouJ National University from 2005 to 2007 clini copathologically according to age, sex. location and clinical findings. They occllrred at the age from 46 to 75 years wi th average age of 60 Four cases occurred in male and 1 in female‘ showing prediJ ection for ma le‘ While four cases occu rred in the maxilla , including 3 cases in the maxillary molar area and 1 in the maxiJJ a ry premola l‘ a rea, only 1 case occurred in the mandibJe. AC showing predorninance in the maxilla over t he ma ndible in our cases in contrast to other case reviews. Three patients presented painful large oral lllcer at the time of admi ssion, a nd other 2 patients presented swol1en mass around the gingivae and alveoJar bone While the clini cal impression of 3 patients were ma lignant tllmor, other 2 patients were amelboJastoma and nicotine stomatitis. The dllration of symptoms before final diagnosis has ranged from 4 months to 2 years Radiogr a phicalJy they showed poorly demarcated radiolucent lesion with irreg비 ar bony destruction. Resected tumors were measured as 6.0X4.5x4.0cm‘ 0‘ 7xO.5xO.3cm, 5.0 x 4.5 X5.0cm. 0.8xO.6 XO.5cm, and 5cm diametel mass respecti vely. Microscopically lymph node metastasis was confirmed in 1 case, but not in others . The tumors showed basic histologic featu re of ameloblastoma with apparent cytologic atypia sllch as pleomol‘ phism‘ hyper chromatism and atypical ffiJ tOSIS Individua l neoplastic cells displayed wide va riations from case to case‘ showing c lear cells with faint PAS positive granules‘ isolated round cells with abundant cytoplasm. s quamoid ceJls and polygonaJ cell s . [mmunohis toc hemical survey was done in 2 cases. all of which showed positivity to pan-cytoker atin a ntibody and p53 a ntibody‘ but negativity to HMB-45, S-100, and SMA One case recurred twice during 2 yeal's after surgery. But 3 cases showed no evidence of recurrence and metastas is. lt seems to us t hat AC have the potential of metastasis and reCllrrence.
        6.
        2007.04 KCI 등재 구독 인증기관·개인회원 무료
        Cholesterol granuloma(CG) occurs frequently in association with chronic middle ear diseases. pa rti cul arly dis eases in the mastoid antrum a nd ai r cells of the tempora l bone. and much less frequent ly in paranasal sinuses, It occurs f1'eq uentJy seconda1'Y to massive hemor1'hage of oral and pal'aol'aJ cysts, Howeve1'. It has nevel' been I'eported to OCCUI' solely wi thout any association of pl'eexisting lesion in the mandibJe We expel'ienced development of unusuaJ cholestel'ol granuloma in the mandible, Seventy year old female pl'e sented diffuse ha1'd swelling on the left mandibular a rea with Iymphadenopathy in the left cer vical Iymph node Radi og1'aphic exarnination showed a well circumsc ribed multi locular radiolucency resembling soap bubble appeara nce with tooth di s placement and root resorption‘ leading to the radiogrphic imp1'ession of dentigerous cyst 0 1' 。dontogenic cys t or amelobJas toma, CT showed bucco-lingua lly undul ating expansi le lesion with co rticated ma l'gin from the left posterior mandibular bocly to the anterior ramus. including #46, #47 ancl #43. and the mass containing in the lesion showed s lightly lower a ttenuation than muscJe leading to the impression of ameloblastoma, The mass aftel' surgical excis ion composed of 3 sac like structures, measuring 4,1 cm, 1, 3cm ancl 1.4cm in diame ter respectively, One sac was t ightl y a ttached to the #46. l'eRembling dentigerous cyst, Mi croscopic examination showed a large numbel' of c h이 es te rol clefts in association with hemol'rhage, hemosiderin pigments and fO l'eign body giant cells, There was no evidence of cyst 0 1' other lesions, CG should be taken into diffe l'enti a l diagnosis in addition to odontogenic cysts and tumors when radiographica lly well ci rcumscribed multilocuJal' radiolucent lesion occurs
        7.
        2007.04 KCI 등재 구독 인증기관·개인회원 무료
        [n order to obtain the trlle expected DNA prod uct from PCR and RT-PCR using genornic DNA or cDNA reversely transcribed from mRNA. the PCR should be done in an appropriated condition. Sometimes the PCR was repeatedly fail ed. and cventllally the PCR product was turned out to be nonspecific and rudimentary . And more‘ t he PCR prodllctwas not reproducible even though careflll repeat of experiments. As the PCR was based on the exact primel hybridization. the condition of primer hybridization should be properly controlled by a nnealing temperatllre. But the selection of primer seqllences for targeting a specific gene is mostly important. A new method of primer eval uation is now available llsing DNA base pair polarity program. This study presents an example of PCR targeting to human Bax gene using genomic DNA. The DNA base pair polarity theory can di vide the genetic cord into propel DNA segments and calclllaLe their DNA base pair hybridization energy. Thus. mathematically the degree 0(' exact primer hybridization can be expected for the t r1l8 targeting of PCR. However, the DNA base pair polal'ityanalysis demonstrates that the more frequent number of DNA segment incl'eased the specificity of PCR. but decreased its sensitivity . While the greater polarity of DNA segment composed of increased nllmber of polarized DNA base pairs showed increased sensitivi ty 0 1' PCR. bllt relati vely decreased specificity of PCR. With the mllltiple analysis of PCR. especially for PCR cloning from the gDNA and cDNA, we found that the primers themselves showed secondary strllcture of partial hybridization between sameprimers or each pair primers. The DNA base pail‘ polarity signal can directly demonstrated symmetric sequences 0 1' each primer. and also can distinguish the dimmer formation from each pair primers. At least the symmetric seqllence of fOlll‘ base pairs dramatically showed the dimrner formation. On the other hand. in addi tion Lo the statlls of DNA base pair polarity the three-dimensional strllctllre of DNA dOllble helix targeted by the primer seqllences may affect the sensitivity and specificity of PCR detection. The present study introduced a new method of primer evalllation and selection in order to obtain abundant and exacL! y-trlle DNA product for genomic ffilltation analysis and gene expression profï le
        8.
        2007.04 KCI 등재 구독 인증기관·개인회원 무료
        Epithelial myoepithelial carcinoma(EMC) is an uncommon malignant sali va ry gland neoplasm, compri sing about 1% 。f salivar y gland neoplasms, They are histologically composed 01' biphasic cell s such as myoepithelial cells and ductal cells EMC occurs predominantly in the major salivary glands, par t icularly in the par otid gland, They have been reported to occur onJy 10-15% in t he intraoral minor salivary glands, The authors experi enced 4 cases of EMC in Department of Oral Pathology in Seoul National University Dental Hospital from 1995 to 2007‘ and reported them with revi ew of li terature, They occurred at the age [rom 34 to 75 years with average age of 54, Three cases occurred in f'emale and 1 in male, showing predominant occurrence in female, Al I of them occurred in the f100r of mouth Three patients presented localized swollen mass at the time of admission, One patient manifested pain with surface n ecrotic ulcer, and others did not complain any symptoms, The duration of symptoms before diagnosis has ranged f rom three mont hs to 2 years in our cases Microscopically, they growed in double layered ductal structure composed 。f' ductal cells of the inner luminal layer which showed positive immunohistochemical reaction to cytokeratin and rnyoepithelial cells 01' the outer peripheral layer identifi ed by the positive reactivity to S-100 and srnooth muscle ac tin antibody, They did not show perinem al invasion‘ but invasíve growth into adjacent tissue, AII of them did not show in vasion into t he underlying bOl1e While 3 pat ients were treated with total excision of tω110 1' mass wi thout n。 evidence of recurrence a ncl metastasis, a 75 year old patient gave up receiving t reatment at the t irne of diagnos is, and then died 01' the cancer 5 years after init ial diagnosis, It seems that EMC of the intraoral minor salivary gland is a tumor 01' low grade malignancy with low potent ial of recurrence and metastasis
        9.
        2005.10 KCI 등재 구독 인증기관·개인회원 무료
        Gene reg비 at i o n during the human craniofacial development is not well understood In effort to understand n ewly identifï ed genes that may play role(s) in the human craniofacial development, non-redundan t genes were isolated from the s ubtracted cDNA libra ry of human embryonal craniofacial tissues and examined their possible structu ral rolc in parallcl with thosc gcncs from isolatecl human c h o nclroc)πes cDNA library. Fifty genes were init ia ll y chosen from 398 clones iso latecl were used for selective dominant expression in both chondrocytes and the craniofacial sections of 10 weeks old human embryo by in situ hybridization method. Based upon the high levels 。f expression, we have identifi ecl seven unknown genes; ch89, ch96. ch129. ch 153. ch 276 ch285. and ch334 . In 。rder to unde rs tancl the possi ble role of these genes‘ the structural simulation of the expressed proteins were constructecl by Sybyl 6.6 program. Ch 276 gene was same with a clone, c14 0 1' f173. registered in GenBank(NM_022489) a nd is composed 0 1' 323 amino acids having a reverse s ignaling domain from the extra- cellular matrix(C-terminal) to cell membrane(N-terminal) and 12 turns of helical structure. Gene protein also r etains a famil iar fïbronectin binding domain(RGD). three s ites 0 1' Ca ion binding motifs. cAMP- and cGMP-dep endent protein kinase phos phorylation site, two regions of protein kinase C phosphorylation s ites. glyco- saminoglycan attachment s ite ancl N-glycosylation site. transmembrane and Al kaline Phosphatase active s ite domains This newly iclentifï ed human protein from human choncl rocytes cDNA library appearecl to be related to a known calcification s ignaling protein. was named as Ca lsin(Ch276) . Ch153 appeared to be related a family of anti-microbial peptide acting as an inflammation mediator and Ch334 clone as a zinc finger protein whose expression in creases in human adult ti ssue‘ These results suggest that these novel genes ident i!ï ed from human chondrocytes rnay provide a new path 0 1' embryonic cartilage development and human craniofacial development.
        11.
        1999.12 KCI 등재 구독 인증기관·개인회원 무료
        12.
        2018.12 KCI 등재 서비스 종료(열람 제한)
        Roasting has revealed coffee’s potentials as a good source of bioactive compounds. This study was done to investigate the quantitative presence and activity of bioactive compounds including caffeine, chlorogenic acid (CGA), amino acids, and antioxidant capacity on Coffea arabica L. (Guatemala finca San Sebastian) and C. robusta L. (India Azad Hind). Analysis was performed on Green Bean (GB) Medium-Light (ML), Medium (ME) and Medium-Dark (MD) samples of both varieties. From the results, caffeine content was highest in ME samples of both varieties. GB samples of both varieties had high CGA content which decreased after increasing roasting time and temperature. Most amino acids in GB samples was highest, however, glutamic acid, valine, tyrosine, isoleucine, leucine and phenylalanine had highest quantitative increase in ME samples for both varieties. IC50 of DPPH and ABTS radical scavenging activity was highest in ML samples of both varieties. IC50 of reducing power and total phenolic content was highest in GB sample of both varieties but decreased after increasing roasting conditions. Generally Robusta had the highest quantity of bioactive compounds and antioxidant activity. From this study, the optimal roasting condition for coffee is ME above which there is a significant reduction of bioactive compounds and antioxidant activity.
        13.
        2014.07 서비스 종료(열람 제한)
        Foxtail millet (Setaria italica L.) is the second most widely cultivated species of millet, especially in East Asia and is a tractable experimental model crop for studying functional genomics of millets. However, insufficient researches had been conducted about the foxtail millet germplasm and is significantly impeding its genetic improvement. We attempted to develop EST-derived-SSR (eSSR) markers and utilize them in genetic comparison of germplasm and transferability. A total of 66,027 foxtail millet EST sequences and 42,754 genomic sequence were deduced transcriptom. Approximately 42,000 single tone contigs were generated using DNAstar 5.0 software for redundancy minimization. Nearly 33% of the 14,012 unigenes contained SSRs, but primers were designed for a total of 314 microsatellites concentrating with more than 24 bp of repeats. A total of 314 primers were successfully designed with more than 24 bp of repeats. From these microsatellites, 56 primer pairs were showed polymorphism with over than 15 bp differences among 96 accessions collected from different countries. Polymorphic information content (PIC) value ranged from 0.020 to 0.700 with an average of 0.381 indicating moderate level of informativeness within these EST-SSRs markers. The EST-SSR markers developed in this study will serve as a useful source for genetic studies, such as genetic variability, transferability, association mapping, and molecular breeding
        14.
        2014.07 서비스 종료(열람 제한)
        Rice blast (Magnaporthe oryza B.) is one of the most widespread and devastating diseases of rice. Screening of valuable genetic resources harboring resistance genes is one of the most efficient approaches against blast disease. Because the bioassay to rice blast in the field shows high variations, this study has performed to provide DNA profiles in the accessions of diverse countries using major blast resistant genes linked markers, identified and mapped in different genotypes of rice. Because durable resistance to blast is controlled by a combination of major resistance genes, we surveyed the distribution of blast resistant genes in the 1,500 accessions using major 12 blast resistance genes linked markers. These resistant genes found that the frequency distribution of Pi-39 (66.9%), Pik-m (41.9%), Pit (40.5%), Pii (21%), Pib (19.3%), Pi-d(t)2 (12.7%), but Pita, Pita/Pita-2, Pik, Piz-t, Pi5 genes were identified in less than 10% frequency. Most of accessions contain from 1 to 4 different resistant genes. Pi39 and Pik-m genes amplified in the 69.1% and 51.7% among 356 Korean accessions, Pi39 (79.6%) and Pib (55.8%) in 113 China, Pit (80.6%) and Pib (32%) in 103 Philippines, respectively. In this study, we evaluated the blast resistance degree and the information about the distribution of rice blast resistant genes in rice germplasm. This study will help to develop effective strategies for managing rice blast disease in rice germplasm.
        15.
        2012.07 서비스 종료(열람 제한)
        The genus Rubus belongs to the Rosaceae family and is comprised of 600-800 species distributed worldwide. Understanding the genetic relationships and genetic structure in Rubus species is important for enabling efficient management, conservation, characterization and utilization of the species. However, as a minor crop, genetic research foundation was limited to explore genetic diversity and relationships in Rubus species. The present study shows the results of application SSR markers that were developed from SSR-enriched libraries of the one Rubus species (Rubus coreanus Mique.) in our previous study. We used 34 polymorphic microsatellite markers to analysis of genetic diversity within the Rubus species, including redraspberry, blackraspberry, blackberry and mountainberry. All the 34 SSR primers pairs produced 483 polymorphic and reproducible amplification fragments. The largest number of alleles per primer pair was confirmed at GB-RC-167, GB-RC-100, GB-RC-076 and GB-RC-245, which contained 26, 25, 23 and 21, respectively. An average value of polymorphic information contents (PIC) were 0.74 with a range of 0.36 to 0.92. Population structure and phylogenetic analyses showed that all Rubus species formed three largely distinct clusters, which were confirmed by principal coordinate analysis (PCoA). We obtained the results that the developed SSR markers showed a substantial degree of genetic diversity in the various Rubus species distributed in Korea.
        16.
        2010.06 KCI 등재 서비스 종료(열람 제한)
        18.
        2009.03 KCI 등재 서비스 종료(열람 제한)
        20.
        2005.06 KCI 등재 서비스 종료(열람 제한)
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