951
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Chong Y, Lee HJ, Lee SY, Jahng JS, Yang KH. Pasteurella multocida infection of the calf in a patient who had moxa cautery treatment for degenerative arthritis. Yonsei Med J 1982; 23:65-70. [PMID: 7168199 DOI: 10.3349/ymj.1982.23.1.65] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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952
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953
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Lee SY. [The possible role of vitamin K compound in oxidative phosphorylation in Saccharomyces cerevisiae (author's transl)]. Zhonghua Min Guo Wei Sheng Wu Ji Mian Yi Xue Za Zhi 1981; 14:27-40. [PMID: 7021081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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954
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Lee SY, Moore SE, Mabee MS. Selective-Differential Medium for Isolation and Differentiation of
Pectinatus
from Other Brewery Microorganisms. Appl Environ Microbiol 1981; 41:386-7. [PMID: 16345712 PMCID: PMC243704 DOI: 10.1128/aem.41.2.386-387.1981] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An agar medium, LL-agar (lactate-lead acetate) was designed to selectively differentiate members of the genus
Pectinatus
(S. Y. Lee, M. S. Mabee, and N. O. Jangaard, Int. J. Syst. Bacteriol.
28
:582-594, 1978; S. Y. Lee, M. S. Mabee, N. O. Jangaard, and E. K. Horiuchi, J. Inst. Brew.
86
:28-30, 1980) from other brewery microorganisms. Selectivity was achieved by the use of sodium lactate as the sole source of carbon and phenylethyl alcohol as an inhibitor for aerobic gram-negative bacteria and yeast. Differentiation was established by the introduction of lead acetate into the medium, which reacted with the H
2
S liberated by
Pectinatus
and resulted in a blackening of the
Pectinatus
colonies while the other brewery organisms, when present, remained white. In combination with the Lee tube (J. E. Ogg, S. Y. Lee, and B. J. Ogg, Can. J. Microbiol.
25
:987-990, 1979) and this medium, isolation of
Pectinatus
organisms from beer samples was accomplished with convenience and simplicity.
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Affiliation(s)
- S Y Lee
- Research and Development Department, Adolph Coors Company, Golden, Colorado 80401
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955
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Huang CC, Horne CC, Lee PP, Chang YT, Lin JC, Hung PL, Lee SY, Lin SH, Huang IC. Follow-up study of the nephrotic syndrome in children treated with steroids. Taiwan Yi Xue Hui Za Zhi 1981; 80:225-38. [PMID: 6942109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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956
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Lee SY, Guttenplan JB. A correlation between mutagenic and carcinogenic potencies in a diverse group of N-nitrosamines: determination of mutagenic activities of weakly mutagenic N-nitrosamines. Carcinogenesis 1981; 2:1339-44. [PMID: 7034988 DOI: 10.1093/carcin/2.12.1339] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The mutagenic activities of a diverse group of N-nitrosamines were measured in Salmonella typhimurium TA 100 under conditions designed to maximize metabolism of N-nitrosamines and enhance their mutagenic effects. These conditions were also chosen since some of the carcinogens were previously reported to be non-mutagenic or of questionable mutagenic activity and some only became mutagenic after the bacteria were exposed to a "threshold does" of metabolites. The mutagenic potencies spanned a range of 10(5)-fold and correlated well with semiquantitative carcinogenic potencies taken from the literature. This correlation appears to be the strongest yet reported for any particular class of compounds. In addition, the mutagenic activities of a number of carcinogens, previously reported to be non-mutagenic, were determined. Among the structural features necessary for high mutagenic activity in this group of compounds was a potential, unsubstituted methylating or ethylating group. Substitution of alkyl, hydroxyl, methoxyl, and cyano moieties at the alpha or beta carbon of these groups reduced mutagenic activity.
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957
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Kim KS, Chong Y, Lee SY, Kim KY. Shigella flexneri bacteremia: a case report. Yonsei Med J 1981; 22:21-5. [PMID: 6753357 DOI: 10.3349/ymj.1981.22.1.21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
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958
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Choy YM, Wong SL, Lee SY. Cross reaction of bacteriophage: cleavage of Klebsiella K31 capsular polysaccharide by E. coli capsule bacteriophage 29 endoglycosidase. Mol Immunol 1980; 17:391-3. [PMID: 7003359 DOI: 10.1016/0161-5890(80)90060-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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959
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960
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961
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962
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Abstract
A new type of tube (the Lee tube) has been developed for use in the cultivation and enumeration of obligate anaerobes. The Lee tube is a double-walled, screw-capped tube which allows the formation of a thin cylinder of agar medium between the two walls. Anaerobiosis is achieved through deoxygenation of the deep cylinder of agar during sterilization, a minimum of head space, and use of a reducing agent to absorb oxygen introduced during the inoculation procedure. For several species of Clostridium, Bacteroides fragilis, Fusobacterium necrophorum, Veillonella alcalescens, and Pectinatus cerevisiiphilus, colony counts of cultures in the Lee tubes were comparable with those obtained in pour plates incubated in a BBL GasPak system and in anaerobic roll tubes.
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963
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Lee SY, Shen MC, Wang CH, Liu CH, Lin KS. Studies of leukocyte alkaline phosphatase activity in hematological disorders. Taiwan Yi Xue Hui Za Zhi 1979; 78:573-81. [PMID: 290731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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964
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Lee YT, Chen PS, Chu SH, Tseng CD, Liau CS, Tseng YZ, Lee SY, Wu TL. Electrophysiological proof of a successful surgical division of the Kent bundle in Wolff-Parkinson-White syndrome. Taiwan Yi Xue Hui Za Zhi 1979; 78:433-44. [PMID: 288838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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965
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966
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967
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Chong Y, Yi KN, Lee SY. An evaluation of the effect of one-day blind subculture in the initial detection of Salmonella typhi positive blood cultures. Yonsei Med J 1979; 20:33-8. [PMID: 392958 DOI: 10.3349/ymj.1979.20.1.33] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
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968
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Kapadia GG, Kortright KH, Lee SY, McIntire KR, Waldmann TA. Isolation of human alpha-fetoprotein in two fractionation steps and demonstration of homogeneity. Prep Biochem 1979; 9:109-32. [PMID: 86988 DOI: 10.1080/00327487908061678] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Human alpha-fetoprotein (hAFP) has been isolated from cord serum in 40% yield using an isolation procedure consisting of only two major steps: affinity chromatography followed by preparative polyacrylamide gel electrophoresis (PAGE). The final product appeared homogeneous on the basis of five independent criteria for purity. Sodium dodecyl sulfate gel electrophoresis (SDS-PAGE) demonstrated a single polypeptide chain with molecular weight of 71,000. The protein exhibited an apparent isoelectric point (pI') of 4.85, molecular radius of 3.0 nm and a valence (net H+/molecule) of 21.9 derived from computation of analytical PAGE data. The two-step isolation procedure made it possible for a single operator to isolate milligram amounts of hAFP in a matter of weeks.
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969
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Lee YT, Liau CS, Tseng CD, Lee SY, Wu TL, Tseng WP, Chen CM, Hsu CJ. Serum digoxin concentration among Chinese patients. Taiwan Yi Xue Hui Za Zhi 1979; 78:28-41. [PMID: 286746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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970
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Fielding WL, Lee SY, Friedman EA. Continued pregnancy after failed first trimester abortion. Obstet Gynecol 1978; 52:56-8. [PMID: 683631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Forty-six patients with unintentional continued pregnancy were detected among a series of 65,045 first trimester abortions. Patients at greatest risk are those with very early pregnancy and those with marked uterine anteversion or retroversion or with uterine anomaly. Attention to gestational duration and uterine size as related to the amount and character of the evacuated tissue, particularly stressing identification of villi and fetal tissues, may help avoid this problem.
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971
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Lee SY, Bailey SC, Apirion D. Small stable RNAs from Escherichia coli: evidence for the existence of new molecules and for a new ribonucleoprotein particle containing 6S RNA. J Bacteriol 1978; 133:1015-23. [PMID: 342486 PMCID: PMC222114 DOI: 10.1128/jb.133.2.1015-1023.1978] [Citation(s) in RCA: 101] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Small stable RNA molecules of Escherichia coli other than 5S (rRNA) and 4S (tRNA) were studied. Two of the molecules corresponded to 4.5S and 6S RNA, which have been reported previously. The third stable RNA molecule, 10S RNA, has not been described before. RNA labeled with (32)P(i) or [(14)C]uracil for a relatively long time, when separated in 5%/12% tandem polyacrylamide gels, displayed three bands corresponding to 10S, 6S, and 4.5S RNA in addition to rRNA and tRNA bands. These RNAs were stable in pulse-chase-labeling experiments. The amount of these RNAs was small, comprising only 0.2 to 0.5% of the total (32)P incorporation. However, this amount represented a large number of molecules; for 6S and 4.5S, it was about 1,000/DNA molecule. These three RNAs were found in the postribosomal supernatant fraction. None of them was found in purified nucleoid fractions in which the tightly coiled DNA molecules were contained. Of these three RNAs, 6S RNA was unique in that it seemed to exist in a ribonucleoprotein particle. All these RNAs, as well as tRNA, were very stable in the cell under various physiological conditions. 5S RNA was less stable. On the other hand, purified 6S RNA was more susceptible than tRNA to cell nucleases when incubated with cell extracts, suggesting that, being in a particle, it is protected from cell nucleases.
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972
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973
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Chong Y, Yi KN, Lee SY. Biochemical characteristics and antibiotic susceptibilities of Serratia marcescens isolated from clinical specimens. Yonsei Med J 1978; 19:32-8. [PMID: 382648 DOI: 10.3349/ymj.1978.19.1.32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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974
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Chong Y, Kim SO, Lee SY. Modified dextrose starch agar for the preservation of Neisseria gonorrhoeae. Yonsei Med J 1978; 19:70-4. [PMID: 112787 DOI: 10.3349/ymj.1978.19.1.70] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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975
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Lee SY, Lim JK. A comparative study of the effect of oxantel-pyrantel suspension and mebendazole in mixed infections with Ascaris and Trichuris. Drugs 1978; 15 Suppl 1:94-8. [PMID: 657997 DOI: 10.2165/00003495-197800151-00018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A comparative trial was carried out in 4 orphanges in Seoul, to compare the anthelminthic efficacy of oxantel-pyrantel suspension and mebendazole tablets against mixed infections of Ascaris lumbricoides and Trichuris trichiura. 40 patients were divided into 4 groups and received oxantel-pyrantel suspension at 15 or 20mg/kg once only or on 2 consecutive days. Another group of 20 patients was treated with 100mg of mebendazole twice a day for 3 days. Both drugs achieved a 100% cure rate for Ascaris infections. Against Trichuris infections, the average cure rate and egg reduction rate of oxantel-pyrantel treated groups was 87.5% and 92.3% respectively, and that for mebendazole was 65% and 89.1%. There were no side-effects. The results of the present study suggest that oxantel-pyrantel is more effective in the treatment of mixed infections of Ascaris and Trichuris, and was more acceptable to the patients, than mebendazole.
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976
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Abstract
The site of umbilical cord attachment in ruminants indicates the limited segment of the uterus where the blastocyst attachment occurs and could have potential significance for locating presumptive nidation sites. Measurements of the site of cord attachment were made on impala (Aepyceros melampus) and common duiker (Sylvicapra grimmia) at several stages of gestation. Both implant only in the right uterine horn although they ovulate from either ovary. Relative to uterine length, cord attachment in impala is somewhat closer to the cervix than it is in common duiker. As pregnancy advances in common duiker, the relative position of cord attachment becomes closer to the tubal end. This relationship was not seen in impala and may perhaps to be attributed inadequate data. Upon extrapolation of the data from common duiker, a presumptive attachment area is suggested for this species. This region is located at about 41% of the distance from the internal cervical os to the uterotubal junction. Similar cord attachment data could be used in any ruminant species to indicate the existence and location of a specific nidation site.
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977
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Lien WP, Lee YS, Chang FZ, Lee SY, Chen CM, Tsai HC. The sick sinus syndrome: natural history of dysfunction of the sinoatrial node. Chest 1977; 72:628-34. [PMID: 913143 DOI: 10.1378/chest.72.5.628] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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978
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Chang DK, Ahn YM, Chong Y, Lee SY. A comparative study of the VDRL and FTA-ABS tests in Korea. Yonsei Med J 1977; 18:52-8. [PMID: 360630 DOI: 10.3349/ymj.1977.18.1.52] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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979
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980
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981
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Chong Y, Yi KN, Lee SY. Effect of hypertonic sucrose on the growth of Salmonella typhi in experimental blood cultures. Yonsei Med J 1976; 17:136-41. [PMID: 1030560 DOI: 10.3349/ymj.1976.17.2.136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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982
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Kuramoto M, Ishimura Y, Morimoto J, Okubo T, Lee SY. [Studies on no effect dose of tobramycin and its recovery test in rats (author's transl)]. Jpn J Antibiot 1975; 28:767-74. [PMID: 1195514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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983
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Kuramoto M, Ishimura Y, Morimoto J, Lee SY, Katori T. [On toxicity of massive administration of sodium cephalothin. II. Chronic toxicity (author's transl)]. Jpn J Antibiot 1975; 28:195-203. [PMID: 1152278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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984
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985
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Chong Y, Yi KN, Lee SY. Effects of high concentrations of sucrose in blood culture media with special reference to the cultivation of Salmonella typhi. Yonsei Med J 1975; 16:99-106. [PMID: 1232715 DOI: 10.3349/ymj.1975.16.2.99] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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986
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987
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Chen SN, Lee SY, Liu KH, Tseng PT, Suzuki T, Sato Y, Sekikawa H, Otsuru M. Epidemiological observations of angiostrongyliasis in Taiwan. 2. Skin test with purified antigen. Taiwan Yi Xue Hui Za Zhi 1974; 73:411-6. [PMID: 4530031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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988
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Chen SN, Liu KH, Suzuki T, Lee SY, Wang LY. Toxoplasmosis in Taiwan. Prevalence of antibodies in cord blood. Taiwan Yi Xue Hui Za Zhi 1974; 73:324-7. [PMID: 4613799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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989
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Chen SN, Lo CT, Lee SY, Liu KH. Angiostrongylus cantonensis infection in Achatina fulica from Taiwan. Zhonghua Min Guo Wei Sheng Wu Xue Za Zhi 1974; 7:62-3. [PMID: 4479559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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990
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Chong Y, Ine SH, Choe MH, Yi KN, Lee SY. Anaerobic bacteria in routine diagnostic cultures. Yonsei Med J 1974; 15:1-10. [PMID: 4463581 DOI: 10.3349/ymj.1974.15.1.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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991
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Chong Y, Lee SY. Comparison of thioglycollate media, modified thioglycollate media, and GAM for the cultivation of non-sporeforming anaerobes. Yonsei Med J 1974; 15:136-46. [PMID: 4469706 DOI: 10.3349/ymj.1974.15.2.136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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992
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Lee SY, Chen SN, Suzuki T, Liu KH, Lin SY, Tseng PT. Toxoplasmosis in Taiwan. 3. Evaluation of a modified technique for detection of cysts of Toxoplasma gondii in swine brains. Taiwan Yi Xue Hui Za Zhi 1973; 72:91-5. [PMID: 4572227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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993
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994
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Mendecki J, Lee SY, Brawerman G. Characteristics of the polyadenylic acid segment associated with messenger ribonucleic acid in mouse sarcoma 180 ascites cells. Biochemistry 1972; 11:792-8. [PMID: 4536742 DOI: 10.1021/bi00755a018] [Citation(s) in RCA: 287] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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995
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996
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997
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Abstract
Epithelial and fibroblast cells were obtained from cultures of amniotic fluid cells. Epithelial cells demonstrated high activities of histidase. In contrast, histidase activity was not detected in fibroblasts derived from the same original culture. This observation indicates that cultures of amniotic fluid cells consist of cells with different biochemical properties as well as morphological characteristics.
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998
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Lee SY, Mendecki J, Brawerman G. A polynucleotide segment rich in adenylic acid in the rapidly-labeled polyribosomal RNA component of mouse sarcoma 180 ascites cells. Proc Natl Acad Sci U S A 1971; 68:1331-5. [PMID: 5288382 PMCID: PMC389183 DOI: 10.1073/pnas.68.6.1331] [Citation(s) in RCA: 438] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The rapidly-labeled polyribosomal RNA component from mouse sarcoma 180 cells is retained on nitrocellulose (Millipore) membrane-filters at high ionic strength. This property is due to the presence of a polynucleotide sequence rich in adenylic acid that resists both T(1) and pancreatic RNase digestion. The resistant material shows sedimentation characteristics close to those of transfer RNA. The RNA molecules that contain this material can be separated from the rest of the polysomal RNA by differential phenol extraction with neutral and alkaline Tris buffers. Synthetic poly(A) exhibits the same behavior as the rapidly-labeled polysomal RNA with respect to Millipore binding and phenol fractionation. The characteristics of the rapidly-labeled polysomal RNA component permit its isolation free of ribosomal RNA.
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999
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Abstract
Addition of nutrients to starved mouse S-180 cells leads to rapid conversion of ribosomal monomers to polysomes. During this process, a portion of the ribosomes originally found in the 17,000 g (10 min centrifugation) supernatant of cell lysates becomes firmly attached to structures sedimenting at 500 g (5 min centrifugation). Electron microscopy of sections of the intact cells showed the change from randomly distributed ribosomal particles to clusters. Association with membranes also became evident. The material sedimenting at 500 g comprised nuclei enclosed in an extensive endoplasmic reticulum (ER) network. This fraction prepared from recovering cells showed numerous ribosome clusters associated with the ER network. The appearance of many of these clusters indicated that the ribosomal particles were not directly bound to the membranes. RNase treatment released about 40% of the attached ribosomes as monomers, and ethylenediaminetetraacetic acid released 60% as subunits. It is suggested that during polysome formation a portion of the ribosomes becomes attached to the membranes through the intermediary of messenger RNA.
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1000
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Lee SY, Krsmanovic V, Brawerman G. Initiation of polysome formation in mouse sarcoma 180 ascites cells. Utilization of cytoplasmic messenger ribonucleic acid. Biochemistry 1971; 10:895-900. [PMID: 5544684 DOI: 10.1021/bi00781a026] [Citation(s) in RCA: 81] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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