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Andreyev AR Norman D Cunningham 2001 Kirsten ras mutations in patients with colorectal cancer: The

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—321. Rask, M., Malm, D., Kristofferzon, M.L., Roxberg, A., Svedberg, P., Arenhall, E., et al. (2010). Validity and reliability of a Swedish version of the Relationship Assessment Scale (RAS): A pilot study. Canadian Journal of Cardiovascular Nursing, 20 (1

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4221 4229 Miranti, C. K., Ginty, D. D., Huand, G., Chatila, T., Greenberg, M. E. (1995) Calcium activates serum response factor-dependent transcription by a Ras- and Elk-1

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Bos, J.L. (1987): Ras oncogenes in human cancer: A review. Cancer Res. , 49 , 4682–4689. Bos J.L. Ras oncogenes in human cancer: A review

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Orvosi Hetilap
Authors: Bálint Tóbiás, Bernadett Balla, János Kósa P., János Horányi, István Takács, Eszter Bölöny, Csaba Halászlaki, Zsolt Nagy, Gábor Speer, Balázs Járay, Eszter Székely, Roland Istók, and Péter Lakatos

1167 1214 Malumbres, M., Barbacid, M.: RAS oncogenes: the first 30 years. Nat. Rev. Cancer, 2003, 3 , 459–465. Barbacid M

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Kamini Vidrawan Ras is a classical Ayurvedic medicine, referred to in Bhaisjya Ratnavali, a book recognized by the Drugs and Cosmetics Act of India. Its usefulness has been stated in erectile dysfunction, impotence, and premature ejaculation. Opium is the major ingredient of formulation which is highly addictive as it contains narcotic alkaloids (morphine, codeine, and thebaine). Opium is a natural product; hence, the morphine content varies from 4–21%. The aim of this study was to develop a simple, precise, rapid, and reliable high-performance thin-layer chromatography— densitometry method for the quantitative estimation of morphine in the tablets of the said Ayurvedic medicines. Aluminum-backed silica gel F254 (20 cm × 10 cm) was used as the stationary phase and ethyl acetate, methanol, and ammonia (85:10:5, v/v) as the mobile phase. The R F value for morphine was 0.36, and the quantitative evaluation of the bands over plates was performed in the reflectance—absorbance mode at 280 nm. The regression analysis of the calibration plot showed good linear relationship between peak area vs. morphine concentration. Linearity was found in the range of 400 to 1200 ng per band, and the amount of morphine was estimated by comparing the peak area of the standard morphine.

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The separation and estimation of natural products by chromatographic techniques such as high-performance liquid chromatography (HPLC) and high-performance thin-layer chromatography (HPTLC) are widely preferred. The present work reveals the quantification of morphine (a regulated narcotic agent) in the Ayurvedic formulation ̀Kamini Vidrawan Raś using reversed-phase HPLC (RP-HPLC). The results obtained herein were compared with the results of earlier reported work using HPTLC. The HPTLC separation of morphine was performed on an aluminum-backed layer of silica gel 60 F254 using ethyl acetate–methanol–ammonia solution as the mobile phase, while RP-HPLC was performed on Kromasil C8-column (150 mm × 4.6 mm, 5 µm) using a mobile phase comprising of N-heptane sulfonate sodium salt–acetonitrile (70:30, v/v) at a flow rate of 1.5 mL min-1. The International Conference on Harmonisation (ICH) guidelines were followed for validation of both the chromatographic methods. Both the developed chromatographic methods are simple, rapid, accurate, and sensitive.

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Abstract  

Simultaneous determination of the two stable boron isotopes was carried out through the measurement of proton induced 2124 keV gamma-ray from11B and 428 keV or 718 keV gamma-rays from10B. Excitation functions were constructed and mean energies for thick target range corrections were calculated. Analysis requires no target preparation. Bombardments last up to 30 min. The sensitivity limit for total boron is 150 μg·g−1 and for isotopic determinations, 0.50 atom%. The relative precision is about 3%.

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, J., Cai, H., Cooper, G. M. (1990) Effect of a dominant inhibitory Ha- ras mutation on neuronal differentiation of PC12 cells. Mol. Cell. Biol. 10 , 5324-5332. Effect of a dominant inhibitory Ha- ras mutation on neuronal

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