• Journal of Pharmaceutical Investigation
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• 제26권2호
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• pp.105-112
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• 1996

The surface of albumin microspheres was modified with methotrexate(MTX) by using 1,3-dicyclohexylcarbodiimide (DCC). Surface-modified albumin microspheres entrapping no MTX (SAMS), free MTX (SAMSF) and MTX-bovine serum albumin(BSA) conjugates(SAMSC) were prepared. The organ-targeting ability of free $[^3H]MTX,\;[^3H]MTX-BSA$ conjugate and the above microspheres was evaluated after i.v. administration of the preparations, equivalent to 150 nCi via the tail vein of mice. The total radioactivity in the lung increased immediately in a few minutes after i.v. injection of the microspheres, and then declined for the period of 3-4 weeks. However, the radioactivity in the liver, spleen and kidney increased slowly during the rapid decrease in radioactivity in the lung. This suggested that the microspheres could be entrapped rapidly in the lung through mechanical filtration because of their large size and slowly redistributed to the liver, spleen and kidney due to either the microspheres being degraded enough for the size to allow passage through the capillary beds of the lung and/or the release of $[^3H]MTX\;or\;[^3H]MTX-BSA$ conjugates from the microspheres. The amount of $60{sim}70%$ of the dose was targeted to the liver after the i.v. injection of SAMS, SAMSF and SAMSC, and the values of $(R_e\;^*\;_{e)liver}$ from the microspheres were $5{\sim}7$ compared to free MTX. This suggested that the liver-targeting ability from surface-modified albumin microspheres could be $5{\sim}7$ times as that of free MTX. The liver-targeted drug was accumulated in the Kupffer cells at the initial stage, thereafter the drug in the Kupffer cell was slowly transferred into the hepatocytes. The value of AUQ for liver from SAMS was higher than that from SAMSF, but much lower than that from SAMSC. This suggest that MTX bound to their surface could be eliminated slower than the entrapped free MTX, and faster than the entrapped MTX-BSA conjugates. This is consistent with the in vitro release rates order in the presence of a proteolytic enzyme. Also, surface-modified MTX was scarcely released in the absence of a proteolytic enzyme. Therefore, the surface-modified MTX nay be released (or eliminated) rapidly from SAMSC at the target site, and thereafter MTX may be released (or eliminated) slowly from the entrapped MTX-BSA conjugates in SAMSC for a long period.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권4호
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• pp.337-344
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• 2000

본 연구에서는 MSI와 구강암과의 상관관계를 규명하기 위하여 17례의 구강암에 대하여 12종류의 marker를 이용하여 MSI 빈도를 조사하였으며, 동시에 p53단백의 과발현과 유전자 돌연변이 양상에 대해서도 알아보았다. 그 결과 4종류 이상의 marker에 대해서 MSI가 나타나는 widespread MSI의 경우 임상병리학적으로 뚜렷한 특징이 없었다. 또한 흡연과 MSI 빈도간에도 연관성이 없었으나 흡연은 p53 유전자의 돌연변이를 증가시켜 암화과정을 촉진하는 작용을 하는 것으로 나타났다.

• 한국식품과학회지
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• 제42권1호
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• pp.1-7
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• 2010

HPLC/APCI-MS에 의한 dithiocarbamate계 분석법을 확립하고 아울러 국내에서 dithiocarbamate계 농약이 사용되는 쌀, 배추, 사과 등 20종 농산물에 대해 잔류실태를 조사한 본 연구의 결과는 다음과 같았다. Dithiocarbamate계 농약 검출건수는 복숭아가 10건 중 3건(30%), 고추가 14건 중 7건(50%), 양파가 12건 중 4건(33.3%), 포도가 12건 중 8건(66.7%), 토마토가 17건 중 7건(41.2%), 감자가 14건 중 4건(28.6%), 구기자가 10건 중 9건(90%), 수박이 10건 중 6건(60%), 양배추가 11건 중 8건(72.7%), 배추가 10건 중 7건(70%), 당근이 12건 중 6건(50%), 오이가 13건 중 8건(61.5%), 쌀이 13건 중 6건(46.2%), 감귤이 11건 중 8건(72.7%), 메론이 16건 중 5건(31.3%), 감이 10건 중 1건(10%), 인삼이 11건 중 1건(9.1%), 대두가 10건 중 2건(20%)으로 100건의 시료에서 42.4%의 검출율을 보였으나 사과와 배 각 10건의 시료에서는 검출되지 않았다. 이 중 기준치를 초과한 농산물은 건 구기자 3건이었으나 기준규격을 설정하여 관리되고 있다.