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Protective Effect of Garlic (Allium sativum L.) Extracts Prepared by Different Processing Methods on DNA Damage in Human Leukocytes (마늘의 조리방법에 따른 DNA 손상 보호 효과의 비교)

  • Kim, Jung-Mi;Jeon, Gyeong-Im;Park, Eun-Ju
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.6
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    • pp.805-812
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    • 2010
  • DNA damage including base modifications, loss of base and breaks in DNA strands can occur by exposure to irradiation, smoking and several components of food. Unrepaired DNA damage is known to lead to cellular dysfunction, cell death, cancer, and other diseases such as arteriosclerosis and diabetes. The protective effect of garlic on oxidative stress induced DNA damage has been reported recently. In this study, we investigated the protective effect of garlic extracts prepared by different processing methods (raw garlic extracts, RGE; grilled garlic extracts, GGE; pickled garlic extracts, PGE) on leukocytic DNA damage using comet assay. Human leukocytes were incubated with ethanol and methanol extract of garlic at various concentrations (1, 5, 10, 50 ${\mu}g$/mL), followed by oxidative stimuli (200 ${\mu}M$ $H_2O_2$ or 200 ${\mu}M$ 4-hydroxynonenal (HNE)). The methanol and ethanol extracts of RGE, GGE, and PGE showed inhibitory activities of DNA damage induced by $H_2O_2$ or HNE. Especially methanol extract of RGE ($ED_{50}$; 13.3 ${\mu}g$/mL) had a higher antigenotoxic effect on $H_2O_2$ induced DNA damage than those of GGE (23.5 ${\mu}g$/mL) or PGE (24.5 ${\mu}g$/mL). HNE induced DNA damage tended to be effectively inhibited by the lower concentration of all garlic extracts. Therefore, garlic might have protective effects against oxidative DNA damage regardless of processing methods (raw, grilled, pickled) which are the general consumed forms of garlic in Korea.

Friction Welding of Ni-Base ODS Alloy Prepared by Mechanical Alloying (기계적 합금법으로 제조된 Ni기 산화물 분산강화 합금의 마찰압접에 관한 연구)

  • 강지훈;박성계;김지순;권영순
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 1994.10b
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    • pp.15-15
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    • 1994
  • M MA ODS 합금의 보다 폭넓용 실용확훌 위해 크게 요구되고 있는 적정 접합기술 개발의 한 방안£로, 마찰압접(Friction Welding) 방법의 가능성옳 조사하기 위하여 마찰압력과 시간, 마 찰 후 접촉압력(Upset Pressure) 풍을 다양하게 변화시켜 접합체톨 제조한 후, 접합체 강도에 대한 인장시험과 접합계연의 결합 및 미세구조에 대한 현미경 관찰, EDS에 의한 원소분석, 접 합이옴부의 경도분포와 파단면 분석 풍율 행하였다. 실험에 사용된 모재는 기계적 합금법으로 제조된 Inca사의 Ni기 MA 754 합금이었으며, 직경 l 10 mm, 길이 50 mm로 가공한 후, 아세통£로 초음파 세척하여 접합에 사용하였다. 접합온 브 레이크식 마찰압접기틀 사용하여 행하였으며, 회전시험편의 회전수는 2400 rpm이었A며, 다른 한쪽의 고정시험편과의 마찰압력 및 마찰시간온 각각 50 - 500 MPa과 1-5초로, 또한 업셋압 력도 50 - 600 MPa로 변화시켰다. 이때 업셋압력은 모든 시편에 대해 일정하게 6초동안 가하 였다. 얻어진 접합체는 각 압접조건 당 2개 이상의 접합시험편에 대해 상온 인장강도톨 측정하 였으며, 파단이 일어난 위치를 확인한 후 파면에 대한 분석율 주사전자현미경(SEM)과 에너지 분산형 분광분석기mDS)릎 사용하여 행하였다. 컵합이옴부의 첩합성올 확인하기 위하여, 접합 체를 접합변에 수직으로 절단, 연마한 후 광학현미경과 SEM, EDS 퉁으로 관찰, 분석하여 접 합부의 형상과 결합형성 여부, 접합계면의 미세조직 퉁옳 조사하였다. 또한 마찰압접에 따론 모재와 접합계연부의 경도분포훌 접합이옴부로부터 모재쪽으로 일정 간격율 두어 마이크로 비 커스 경도기로 측정, 조사하였다. 이상의 설험 결과, 다옴과 같온 결론옳 얻었다. ( (1) 접합체 강도가 모채 강도의 95% 이상이 되는 양호한 렵합체흩 얻기 위한 마찰압력 조건 온, 2400 rpm의 회전속도와 6초의 업셋압력 유지시간에서 마찰압력과 업셋압력, 그리고 마찰시 간이 각각 400 MPa 이상과 500 MPa 이상,2초입율 확인하였다. ( (2) 컵합이옴부의 관찰 결과, 모든 마찰압접 조건에서 컵합이옴부는, 기폰 모재의 texture 조직 을 유지하고 있는 모재부 영역(영역 ill)과 첩합계면부에 인접하여 업셋압력이 주어질 때 단조 효과에 의해 계연 외부로 metal flow가 일어나면서 형성된 영역 II, 매우 미세한 결정립으로 구성된 중앙부의 영역 1 로 이투어져 있옴융 확인하였다. ( (3) 최적접합조건이 충족되지 않온 경우, 접합부의 영역 I 에서 관찰된 void와 균열, 불균일한 접합계면 통의 접합결함에 Al과 Y. Ti 퉁£로 구성된 산화물률이 용집되어 있옴을 확인하였 다-( (4) 접합체의 파단 양상온 크게 접합부 파단과 모재부 파단, 이률의 혼합형 파단i로 나눌수 있었다. 모재부 파단의 경우, 파단면이 매끄럽고 파변상의 결정립도 매우 미세하였으며, 산확물 의 용집도 찾아보기 어려웠 나, 접합부 파단의 경우에는 파변의 굴곡이 비교척 심하고 연성 입계파괴의 형태를 보였£며, 결정립도 모채부 파단의 경우에 비해 조대하였다. 조대하였다.

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Students' Perception of and Attitude toward Appearance Regulations of High Schools (고등학생들의 학교 외모규제에 대한 지각 및 태도)

  • Lee, Jung-Hyun;Lee, Yoon-Jung
    • Journal of Korean Home Economics Education Association
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    • v.20 no.2
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    • pp.47-60
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    • 2008
  • The appearance regulations of many middle and high schools have received attention as the social concern over infringement of students' human right is heightened. This study aimed at examining students' perception of and attitude toward appearance-related regulations enforced by high schools in Seoul. For this purpose, a survey was conducted with 866 freshmen and sophomore students from six Co-Ed high schools located in Seoul. Students evaluated each of the 50 appearance-related regulations in terms of how strong they perceive the regulation is enforced in their school, how important they believe the regulation is, and finally, how much they actually observe it. The results indicated that regulations related to school uniforms are perceived important, and also were well-observed. Students, however, showed low levels of observance toward some regulations--i.e., regulations of hair styles or garments worn with school uniforms(coats, scarves, or turtlenecks). Students' personal characteristics were also found to influence their perception and observance of the regulations. This study has an implication for teachers and administers. For these regulations to be more effective, it was suggested that schools communicate the importance of appearance-related regulations to students and convince them, or consider revising their policies to reflect students' perspectives.

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Synthesis of Benzo[c]phenanthridine Derivatives and their in Vitro Antitumor Activities

  • Cho, Won-Jea;Yoo, Su-Jeong;Chung, Byung-Ho;Choi, Bo-Gil;Cheon, Seung-Hoon;Whang, Soon-Ho;Kim, Sin-Kyu;Kang, Boo-Hyon;Lee, Chong-Ock
    • Archives of Pharmacal Research
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    • v.19 no.4
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    • pp.321-325
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    • 1996
  • Aiming at the development of anticancer agents by modification of phenolic benzo[c]phenanthridine alkaloid, additional hydroxyl group was put on C10 position of fagaridine (1) by a biomimetic synthetic procedure to afford 10-hydroxyfagaridine (12). All of the synthetic intermediates were also screened in vitro antitumor activities against five different cell lines as well as 12. Among them the representative cytotoxic results are shown as follows; P-quinone (11) $[ED_50;(A549=0.22; {\mu}g/ml)$, $(HCT;15=0.21 {\mu}g/ml)$, fagaridine (1) $(HCT;15=0.41 {\mu}g/ml)$, olefin (6) $(HCT; 15=0.06 {\mu}g/ml)$, acetal (7) $(SKMEL-2=0.07 {\mu}g/ml)$, dihydrofagaridne (10) $(A549=0.38 {\mu}g/ml)$, 10-hydroxyfagaridine (12) $(A 549=0.45{\mu}g/mi)$. From these observation three main remarks can be drawn; (i) the iminium part of benzo[c]phenanthridine is not essential for showing acitvities, (ii) the additional hydroxyl group did not contribute to enhance the cytotoxicity, (iii) the 3-arylisoquinolin-1(2H)-one derivatives were found to display significant in vitro antitumor activity.

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The Effect of N-Alkyloxycarbonyl Group on the Anticonvulsant Activities of N-Alkyloxycarbonyl-alpha-amino-N-methylsuccinimides

  • Jung, Kyung-Im;Son, Ki-Chun;Kim, Min-Jeong;Lee, Jae-Won;Choi, Jong-Won;Lee, Eung-Seok;Park, Min-Soo
    • Archives of Pharmacal Research
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    • v.21 no.6
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    • pp.759-763
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    • 1998
  • In connection with the development of new anticonvulsant agents with a broad spectrum, we found that N-Cbz-alpha-amino-alkylsuccinimides showed significant anticonvulsant activities, and the pharmacological activities of these compounds were dependent on their stereochemistry and N-substituted alkyl group. These results prompted us to define the effects of other functional group on the anticonvulsant activities of these compounds. Therefore a series of N-alkoxycarbonyl-alpha-amino-N-methylsuccinimide were prepared from N-Cbz-aspartic acid and were evaluated with their anticonvulsant activities againt the MES and PTZ tests, in order to define the effect of N-substituted alkoxy carbonyl group with the anticonvulsant activities. From these studies, it was found that all the tested N-alkoxycarbonyl-alpha-amino-N-methylsuccinimides exhibited significant anticonvulsant activities in the PTZ test and were not active in the MES test. The most active compound in the PTZ test was (S) N-ethoxycarbonyl-alpha-amino-N-methyl-succinimide. We found that the pharmacological activities in the PTZ test were dependent on their N-alkoxycarbonyl groups. They follow as such: The order of anticonvulsant activities for (R) series as evaluated by $ED_{50}$ was N-phenoxycarbonyl=N-4-nitrobenzyloxycarbonyl > N-ethoxycarbonyl > N-allyloxycarbonyl > N-tert. butoxycarbonyl compound: For the (S) series N-ethoxycarbonyl > N-phenoxycarbonyl > N-allyloxycarbonyl compound. From the above results, it was conceivable that N-substituted alkoxycarbonyl group had certain effects on the anticonvulsant activities of N-alkoxycarbonyl-${\alpha}$-amino-N-methylsuccinimides.

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Marine Biodiversity Study and Biotechnology Exploitation in China

  • Liu, J.Y.
    • Journal of Marine Bioscience and Biotechnology
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    • v.1 no.1
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    • pp.40-47
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    • 2006
  • Large scale marine biodiversity studies in China have been carried out for more than half a century since the founding of the Institute of Oceanology, CAS, in 1950. Through a series of coastal and multi-disciplinary oceanographic investigations in the shelf seas and biodiversity studies since the late fifties, a total of 20,278 species of marine biota have been recorded upto 1994. Recent intensive studies have further revealed the richness of marine biota of the China seas,a great number of marine species have been found and many new taxa established. The total species number of main biotic groups increased about 50 % of that estimated in 1994. The results have promoted the fast development of China's marine fisheries, medicine (drug) and biodiversity research, and attracted many scientists, particularly bio-technologists, to join their studies. Environmental deterioration and human activity strongly stressed the sustainable development and conservation of marine bio-diversity, and resulted in the increase of end angered species as record ed in the new published ${\ll}$China Species Red List${\gg}$ with the threatened category of species assessed by adopting the new IUCN criteria. To further reveal the high diversity and their history, present status and future of marine organisms existed in the world ocean, an international Project ${\ll}$Census of Marine Life (CoML)${\gg}$ was established in 2000 in the USA. Scientists predicted that 2 to 3 times of numbers of the known species will possibly be found in various marine habitats, particularly the abyssal ocean. The Research Plan and the Projects were briefly introduced, and the relationship between marine biodiversity and biotechnology was discussed. The Project planned to apply new and high techniques and new equipments on board research vessel and in laboratory. Brief review of recent advances of Chinas' marine biodiversity and biotechnology studies indicated that fascinate results have been achcieved; but further effort should be made to promote the continuous advance of our basic researches and their application in related production and maintain sustainable development.

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Efficacy of Acyclovir on Virus Replication in Infected Tissues and Virus Reactivation from Explanted Tissues in Mouse Encephalitis Model of Herpes Simplex Virus Type 1 (Herpes Simplex Virus Type 1 마우스 뇌염모델에서의 조직내 바이러스 증식 및 재활성에 미치는 Acyclovir의 약효)

  • Lee, Chong-Kyo;Kim, Jee-Hyun;Bae, Pan-Kee;Pi, Mi-Kyung;Kim, Hae-Soo
    • The Journal of Korean Society of Virology
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    • v.29 no.3
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    • pp.165-174
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    • 1999
  • To investigate viral pathogenesis and in vivo efficacy of acyclovir (ACV) in mouse HSV-1 encephalitis models, female BALB/c mice aged 5 weeks were inoculated with strain F either intranasally (IN) or intracerebrally (IC). ACV-treatment by intraperitomeal injection with 0, 5, 10 and 25 mg/kg b.i.d. for 6 days was commenced 1 h after infection. Body weight and signs of clinical disease were noted daily up to 2 weeks. $ED_{50}$ of ACV in IN infection was <5 mg/kg and 14.1 mg/kg in IC infection. Tissues of central nervous system were collected from 2 mice per group everyday up to 5 day p.i. and the virus titers were measured. In IN infection model, high titers in eyes and trigeminal nerves were observed. ACV-treatment showed significant reduction of the titers in all the isolated. In IC infection model, cerebrum, cerebellum and brain stem showed high virus titers. ACV-treatment showed less significant reduction of virus titers than that in IN infection model. Reactivation of explanted trigeminal nerves from mice 30 day p.i. was monitored. In all of ACV treated mice reactivation was observed, i.e. even the highest dose of ACV did not inhibit the establishment of viral latency.

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Analgesic Effects of DA-5018, a New Capsaicin Derivative, after Subcutaneous Injection and Topical Application (새로운 캅사이신유도체 DA-5018의 피하주사 및 국소도포시 진통효과)

  • 김희기;배은주;신명수;손문호;김순희;김원배;양중익;공재양
    • Biomolecules & Therapeutics
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    • v.5 no.2
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    • pp.117-124
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    • 1997
  • The analgesic effects of DA-5018, a new caosaucin derivative, were evaluated in various experimental pain models. Drugs were administered subcutaneously or topically. When drugs were administered subcutaneously, 1) the $ED_{50}$ of DA-5018, morphine . HCI, capsaicin and acetaminophen were 0.091-2.0, 0.3-4.3, 1.4-26.5 and 45.4-643 mg/kg, respectively in various pain or inflammatory models including acetic acid writhing, formalin, tail flick, Randall-Selitto, hot plate and crouton oil-induced ear edema test, 2) the AD2 values (the dose for doubling of pain threshold of vehicle control) of DA-5018, capsaicin and ketoprpgin were 1.07 $\pm$ 0. 18, 23.47$\pm$4.46 and 2.97$\pm$0.43 mg/kg in Freund's complete adjuvant (FCA)-induced arthritic pain model. And by topical application, 1) neither DA-5018 0.3% cream nor Zostrix-HP (capsaicin 0.075%) were effective in formalin test, 2) although DA-5018 0.3% cream significantly inhibited the croton oil-induced ear edema being better than Zostrix-HP and Kenofen (ketoprofen 3%). 3) In FCA model, DA-5018 0.3% cream reversed the decreased pain threshold of arthritic rat from 136.4 g (day 0) to 289.0 g (day 5) and 250.1 g (day 10), which was similar to Zostrix-HP. These results suggest that DA-5018 administered subcutaneously has a potent and broad analgesic spectrum than nonsteroidal antiinflammatory drugs against acute and chronic pain, and by topical application it exerts comparable analgesic and antiinglammaatory effects to capsaicin cream.

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국제양돈수의학회(I.P.V.S.) -수의업무 세계화의 길이 보인다.-

  • 강영배
    • Journal of the korean veterinary medical association
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    • v.32 no.8
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    • pp.535-539
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    • 1996
  • 국제양돈수의학회(International Pig Veterinary Society ; I.P.V.S) 제14차 총회 및 학술대회가 1996년 7월 7일부터 11일까지 이태리 중북부의 대학도시 볼로냐(Bologna, Italy)에서 개최되었다. I.P.V.S.는 1969년에 영국의 캠브리지 (Cambridge, United Kingdom)에서 창립된 이래 1996년 현재 53개 회원국 1,700 여명의 회원을 확보하고 있으며, 세계 각국의 양돈과 수의학에 관심을 가지고 있는 학자, 생산자 그리고 관련업계 인사들의 학술$\cdot$기술 정보교류와 협력을 목적으로 매 2년마다 세계 주요도시를 순회 하면서 개최되고 있다. 앞으로 2년후(1998년도)에는 I.P.V.S.의 탄생국인 영국의 버밍햄(Birmingham, United Kingdom)에서 제 15차 총회 및 학술대회를 개최할 예정이며 2000년대에는 시드니 올림픽과 때를 맞추어 호주의 멜보른(Melboume, Australia)에서 제16차 총회를 개최하기로 결정되어 있다. 금년(1996년도) I.P.V.S 총회에는 우리나라에서 30개 기관/업체로부터 50여명이 참여한 바 있으며 총 27편 (구두 9편, 포스터 18편)의 학술논문을 발표하는 등 눈부신 활약을 보인 바 있다. 금년도 I.P.V.S. 총회의 특징은 돼지의 전염성 질병중 근래에 우리나라에서도 문제시 되고 있는 '돼지 생식기 호흡기 중후군 (Porcine Reproductive and Respiratory Syndrome ; PRRS)'이 세계적인 관심의 대상이었으며, 이태리 양돈병리축산학회 (Societa Italiana di Patologia ed Allevamento dei Suini ; S.I.P.A.S) 주관으로 '돼지 적리 (Swine Dysentery)'에 관한 Satellite Symposium이 개최되었다는 점이다. WTO 이래 어려워지고만 있는 우리나라 축산업 분야중 그래도 비젼이 보이는 양돈산업과 관련하여, I.P.V.S.를 통하여 우리나라 수의업무의 세계화의 길을 찾아보고자, 1 국제양돈수의학회(I.P.V.S)의 역사 (양돈과 수의업무 전문가의 새로운 만남의 장), 2 I.P.V.S.에의 참여(제13차 방콕대회), 3 한국 수의사의 활약(제14차 볼로냐대회), 4 세계화의 길(제15차 버밍햄대회, 제16차 멜보른대회), 5 국내양돈의 문제와 우리가 해야할 일(수의업무 세계화의 길을 찾자)등의 순으로 적어보고자 한다.

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Studies on Digitalis Receptor Desensitization in Rat Ventricle

  • Lee, Shin-Woong-;Jang, Tae-Soo
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1994.04a
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    • pp.301-301
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    • 1994
  • $^3$H〕Ouabain binding parameters(K$\_$D/ and B$\_$max/,) in homogenates prepared fpom control rat ventricular strip and Langendorff preparations which were not previously exposed to ouabain were compared to those in homogenates from ventricular strip and Langendorff preparations that had been first exposed to a complete ouabain dose-response curve(10$\^$-7/M to 10$\^$-4/ M). In rat ventricular strips and Langendorff perfused rat heart preparations, cumulative dose-response cruves of ouabain revealed biphasic positive inotropic effects, a "low-dose" and a "high-dose" effect with ED$\_$50/ values of 0.5${\mu}$M and 35${\mu}$M ouabain, respectively- The "low-dose" effect in rat ventricular strips disappeared or was diminished significantly when the ouabain dose-response curve wag repeated after the washout of the effects of the first curve, whereas the maximal "high-dose" effect was identical in both exposures to oubain. However, there was no change in the "low-dose" effects in both sets of the Langendorff perfused hearts. The contractile activity of the pre-exposed strips did not indicate the presence of residual ouabain since their basal contractile force was decreased 10% compared to initial control. 〔$^3$H〕Ouabain binding parameters, K$\_$D/ and B$\_$max/, were not changed comparing homogenate of control ventricular strips with that of strips pre-exposed to ouabain. These results suggest that digitalis receptor desensitization in the rat ventricular strip may due to the change of post-receptor events induced by ouabain binding to a high affinity site(${\alpha}$$_2$ isoform).

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