• 식물조직배양학회지
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• 제25권6호
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• pp.525-530
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• 1998

인삼의 뿌리절편, 줄기, 엽병에 Agrobacterium을 접종하여 고생장 모상근을 선발하고자 수행하였다. 인삼 뿌리 절편에서 A. rhizogenes R1000과 A. rhizogenes $A_4$에 의하여 모상근이 유도되었으며, 인삼의 줄기 및 엽병에서도 모상근이 유도되었다. 유도된 모상근은 rolC및 virC DNA절편의 확인으로 형질전환체임을 확인하였으며, 균이 제거된 모상근을 선발하였다. 선발된 모상근 300 세포주중 성장과 형태적 특징이 뚜렷한 11 모상근을 선발하였다. 이들 모상근은 주근이 비후된 것, 주근이 가는 것, 측근의 돌기가 많은 것, 측근의 생장이 높은 것 등의 특징을 나타내었다. 이들 11 모상근중 주근이 가늘고 측근의 생장이 왕성한 형태가 모상근의 생장이 좋았으며, 주근이 비후되고 측근의 돌기가 많은 형태는 생장이 낮았다. 본 연구에서 인삼 뿌리절편으로부터 고생장 모상근인 KGHR-1, KGHR-5, KGHR-8을 선발하였다.

• 대한미생물학회지
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• 제16권1호
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• pp.1-5
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• 1981

Shigella is one of the most prevalent pathogens for the diarrhoeal diseases in the developing countries. One hundered and six strains of shigella were isolated from January 1980 to August 1981 at the dept. of clinical pathology, Han Yang Medical Center. Subgroups of these strains were identified as one strain of S. dysenteriae, 98 strains of S. flexneri and 7 strains of S. sonnei. None of S. boydii was observed. Sex ratio, male to female was 48 to 58. Age distribution disclosed 6 cases under one year, 11 cases one to under 2 years and 21 cases(19.8%) two to under 3 years. Subtotal of 0 to 9 years showed 64 cases(60.4%). Susceptibility for antibiotics of these strains revealed dibekacin 100%, sisomicin 100%, amikacin 98.1%, cefazolin 97.2%, tobramycin 97.1%, gentamicin 95.2%, colistin 93.0%, minocycline 89.6%, kanamycin 83.0%, carbenicillin 18.9%, streptomycin 18.9%, tmp-smz 8.6%, ampicillin 2.8% and chloramphenicol 1.9%. Patterns of resistance to sulfa, streptomycin, chloramphenical and tetracycline have already started at the early part of 1960 decade. Although ampicillin was highly sensitive to shigella at the end of 1960 to the early part of 1970 decade, this study has disclosed high resistance to the strains. New antibiotics such as amikacin, cefazolin, dibekacin, gentamicin, and tobramycin have revealed highly sensitive to these strains, however, multiresistance for those antibiotics will be shown to be prevalent in this country within several years, where it is probably related to the unrestricted sale and use of antibiotics in man.

• 대한미생물학회지
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• 제35권3호
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• pp.239-250
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• 2000

Sixty-eight clinical isolates of Stenotrophomonas maltophilia from inpatients of 2 university hospitals in Taegu were epidemiologically analyzed by using the minimum inhibitory concentrations of 25 antimicrobial drugs, biochemical reaction, pulsed-field gel elctropgoresis (PFGE), and PCR with enterobacterial repetitive intergenic consensus sequences as primer (ERIC-PCR). 1. All the strains were susceptible to minocycline. More than 57% were susceptible to sulfisomidine (Su), ciprofloxacin (Ci), Ofloploxacin (Of), nalidixic acid (Na), and chloramphenicol (Cm), and $19{\sim}35%$ to ceftazidime (Cd), trimethoprim (Tp), Ticacillin-clavulanic acid, and cefoperazone-sulbactam. Most isolates were resistant to ${\beta}$-lactam antibiotics such as ampicillin (Ap), carbenicillin (Cb), cefotaxim (Ct), cefoxitin (Cx), and aminoglycosides including gentamicin (Gm), tobramycin (Tb), amikacin (Ak). 2. All the isolates were multiply resistant of 5 to 17 drugs and showed 40 different resistance pattern types. 3. All the strains showed very similar biochemical reactions except ${\beta}$-galactosidase and nitrate reduction test. Fourteen strains selected randomly were classified 10 different pattern type by PFGE and ERIC-PCR. These two methods showed identical result. Four strains isolated from wound in 1994 showed similar MIC pattern and identical API 20NE profile, PFGE, and ERIC-PCR pattern indicating episodes of cross-infection among patients. These results indicate that PFGE or ERIC-PCR profile has comparable discriminatory power for epidemiological typing of S. maltophilia.

• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.778-783
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• 1999

Campylobacter is a pathogen for both humans and animals that can be transferred from animals to humans. Four isolates, which grew under 5-10% $CO_2$ and had small and translucent colonies, were obtained from swine gastric mucosa and characterized using various methods. These bacteria were gram negative, spirally shaped with round ends. One or two non-sheathed polar flagella were observed under electron microscopy. A PCR with species-specific protein (SSP) primers for 16S rRNA gene in Campylobacter produced a typical 462 bp fragment. The isolates had various biochemical and molecular characteristics which differentiated them from other Campylobacters. The isolates were catalase and oxidase positive, urease (rapid) negative, nitrate reduction positive, indoxyl acetate hydrolysis positive, y-glutamyl transpeptidase negative, and alkaline phosphatase negative. All four isolates showed growth at $37^{\circ}C{\;}and{\;}42^{\circ}C{\;}but{\;}not{\;}at{\;}25^{\circ}C$, were resistant to cephalotin and cefoperazone, and susceptible to carbenicillin. The isolates showed various results in the reduction of chloride to triphenyl tetrazolium (TTC) and a susceptibility to nalidixic acid. Western blot analysis of these isolates with antiserum raised against one isolate showed different patterns from those of reference strains. A dendrogram drawn with the RAPD results showed that these isolates belonged to a new Campylobacter spp. group different from those of C. jejuni, C. doylei, C. lari, and C. coli.

• KSBB Journal
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• 제5권3호
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• pp.247-253
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• 1990

고등식물의 형질전환용 유전자운반체로써 가장 많이 사용되고 있는 Ti-plasmid를 이용해서 당근세포를 형질 전환시키기 위한 연구의 일환으로 Agrobacterium spp를 helper로 이용하여 NPT II gene를 함유하고 있는 binary vector GA472를 당근세포에 삽입시켜 kanamycin에 대해 저항성을 나타내는 세포주를 선발하고자 본 연구를 수행하였다. 국내 토양에서 선발한 A.tumefaciens 2종과 disarmes된 PC2760 그리고 hypervirulent균주인 A281에 tri-parental mating 방법에 의해서 binary vector인 pGA472을 도입하여 transconjungants인 A. tumefaciens c-23-1/pGA472,K29-1/pGA472, PC2760/PGA472 그리고 A281/pGA472를 획득하였다. Transconjungants는 plasmid의 분리, 정제방법에 의해서 추출한 후 0.7% agarose gel 상에서 관찰해 본 결과 4균주 공히 NTPII gene이 삽입된 pGA472와 Ti-plasmid를 함유하고 있는 것을 확인 하였다. 확인된 conjugant와 당근정상조직을 동시배양방법에 의해서 형질전환을 유도한 후 정상조직은 전혀 생존이 되지않은 kanamycin에 대해서 저항을 나타내는 callus를 선발할 수 있었다.

• 한국동물위생학회지
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• 제29권1호
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• pp.37-46
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• 2006

The present study was conducted to investigate serologic characteristics, antimicrobial resistance and plasmid profile of 79 E. coli isolated from faecal sample of the wild bird in Busan province (Gangseo, Saha) during the period from November 2004 to February 2005. Many strains were positive for rafiinose (63.3%), sorbitol (96.2%), sucrose (73.4%) and few strains were positive for esculin, arginine dihydrolase, ornithine decarboxylase. Among 79 isolates, O serotypes were O55, O158, O18 and 47 strains (59.5%) were resistant to antimicrobial drugs such as tetracycline (40.5%), carbenicillin (27.8%). 15 strains showed 14 different plasmid bands composed of 1 to 6 bands. They were ranged from 1.6 to 43 kb and harbored 43 kb (11.4%), 5.3 kb (6.3%) and 11.4 kb (5.1%). Plasmid profile of 15 strains were 43 profile (2.5%), 2.4, 43 profile (2.5%) and 5.3, 11.4, 43 profile (2.5%).

• 대한미생물학회지
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• 제13권1호
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• pp.31-36
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• 1978

1977년(年) 대구지방(大邱地方)에서 분리(分離)한 20주(株)의 Salmonella paratyphi A, 55주(株)의 S. typhi, 7주(株)의 Shigella flexneri, 14주(株)의 Sh. sonnei에 대(對)하여 항균제감수성(抗菌劑感受性)을 실험(實驗)하였다. S. paratyphi A는 전부(全部)가 salfisomidine(Sa)에 내성(耐性)이었으나 기타공시약제(其他供試藥劑)에는 전부(全部)가 감수성(感受性)이었고 특(特)히 gentamicin, amikacin, kanamycin에 감수성(感受性)이 강(强)하였다. S. typhi는 1주(株)가 chloramphenical(Cm), tetracycline(Tc), streptomycin(Sm) 및 Sa에 내성(耐性)이었고 R(Cm Tc Sm Sa)를 보유(保有)하고 있었으나 기타(其他) 균주(菌株)는 모든 약제(藥劑)에 감수성(感受性)이었고 특(特)히 ampiallin에 감수성(感受性)이 강(强)하였다. Shigella는 1주(株)를 제외(除外)한 20주(株)가 Cm, Tc, Sm 및 Sa에 고도내성(高度耐性)이었으며 기중(其中) 19주(株)가 plasmid R(Cm Tc Sm Sa)를 보유(保有)하고 있었다.

• 대한미생물학회지
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• 제21권1호
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• pp.17-31
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• 1986

Forty clinical isolates of Serratia marcescens were tested for their susceptibility to 19 antimicrobial drugs and studied on the molecular characteristics of R plasmids. Cefotaxime (Ct) was the most effective drug and only 2 (5%) strains were resistant to this drug. Thirteen to 18% of strains were resistant to cefoperazone (Cz), amikacin (Ak). and trimethoprim (Tp), and 28 to 40% were resistant to piperacillin (Pi), nalidixic acid (Na), gentamicin (Gm), and cefoxitin (Cx). A majority of strains were resistant to carbenicillin (Cb), tobramycin (Tp), kanamycin (Km), and cefamandole (Cd), and all to cephalothin. One half of the isolates were resistant to 10 or more drugs. $MIC_{90}$ of Pi to Gm-resistant strains (Gm') were 8 times higher than that to Gm-susceptible strains (Gm'), but $MIC_{90}$ of Ak, Cx, Ct, and Cz were almost the same between both Gm' and Gm' strains. Nine (23.7%) strains among 38 of multiply drug-resistant S. marcescens transferred conjugally their partial patterns of resistance to E. coli or Klebsiella strains, and two S. marcescens strains producing bacteriocin transferred their resistance to Klebsiella only, but not to E. coli. The plasmid profiles of S. marcescens were studied by the methods of SDS lysis and agarose gel electrophoresis. Twenty-four (60%) strains carried one to four plasmids of 1.4. to 144 Mdal, and conjugative R plasmids of 49 to 127 Mdal were noted in transconjugants. MIC levels of drugs in transconjugants were variable by the R plasmids and recipient strains.

• Journal of Plant Biotechnology
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• 제7권3호
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• pp.203-209
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• 2005

This study was conducted to improve tocopherol (vitamin E) composition in soybean (Glycine max) by introducing a gamma-tocopherol methyl transferase (${\gamma}$-TMT) gene via Agrobacterium tumefaciens-mediated transformation. Immature cotyledon explants were cocultivated with Agrobacterium tumefaciens. Putative transgenic embryos were selected from immature cotyledons on MS medium supplemented with 40 mg/L 2,4-D containing 100 mg/L kanamycin, 500 mg/L carbenicillin and 250 mg/L cefotaxime. Plantlets were developed from somatic embryos, and then transferred to soil. Nineteen regenerated plantlets obtained on the selection medium from 1,460 cotyledons. However, only 9 plantlets were confirmed as transformed plants. Integration of the transgene into the soybean genomic DNA was confirmed by PCR and Southern blot analysis. HPLC analysis showed that the content of ${\alpha}$-tocopherol in transgenic soybean seeds (AT-1) was approximately 4-fold higher than that of non-transgenic plants. Conclusively, we obtained the transgenic soybean having increased ${\alpha}$-tocopherol content by the overexpression of ${\gamma}$-TMT transgene.

• 대한수의학회지
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• 제23권2호
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• pp.205-209
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• 1983

Some investigations on chronic mastitis in dairy cattle in Kyungnam Province during the year 1982 were conducted with the special reference to the causative agents and their drug resistance. Milk samples from 46 isolated cases of chronic mastitis cattle were investigated bacteriologically and the organisms recovered were examined for their drug susceptibility against the major antibiotics used in this country by the use of disk diffusion susceptibility test. Four major causative agents involved in chronic mastitis were in order of prevalence Staphylococcus aureus (32.6%), Escherichia coli (28.3%), Streptococcus agalactiae (8.7%) and Candida albicans (8.7%). Staph. epidermidis, Streptococcus uberis, Klebsiella pneumoniae and Candida subtropicalis were found to be one of the minor agents. The majority of staphylococcal isolates were highly resistant to the most of antibiotics employed while 8% of them were resistant to gentamicin and 32% to chloramphenicol. The percentages of staphylococcal cultures resistant to penicillin, lincomycin. streptomycin, methicillin, oleandomycin, tetracycline, cephalothin, ampicillin and erythromycin were 100%, 96%, 96%, 92%, 84%, 84%, 80%, 76%, and 64% respectively. Streptococcal isolates were also highly resistant to the majority of the drugs used although 85.7% of them were susceptible to gentamicin. All Escherichia coli isolates were found to be resistant to erythromycin, lincomycin and penicillin while the majority of them were resistant to ampicillin (92.9%), carbenicillin (85.7%), oleandomycin (85.7%), streptomycin(85.7%), kanamycin (78.6%), methicillin (78.6%) and tetracycline (71.4%). The percentages of E. coli cultures resistant to gentamicin, nitrofurantoin, cephalothin and chloramphenicol were 21.4%, 21.4%, 35.7% and 50.0% respectively.