| Herb-drug interactions: a literature review Z Hu, X Yang, PCL Ho, SY Chan, PWS Heng, E Chan, W Duan, HL Koh, ... Drugs 65, 1239-1282, 2005 | 891 | 2005 |
| Herbal bioactivation: the good, the bad and the ugly S Zhou, HL Koh, Y Gao, Z Gong, EJD Lee Life sciences 74 (8), 935-968, 2004 | 361 | 2004 |
| Chinese proprietary medicine in Singapore: regulatory control of toxic heavy metals and undeclared drugs HL Koh, SO Woo Drug safety 23 (5), 351-362, 2000 | 271 | 2000 |
| Ultra‐performance liquid chromatography/time‐of‐flight mass spectrometry based metabolomics of raw and steamed Panax notoginseng ECY Chan, SL Yap, AJ Lau, PC Leow, DF Toh, HL Koh Rapid Communications in Mass Spectrometry: An International Journal Devoted …, 2007 | 225 | 2007 |
| Simultaneous determination of synthetic phosphodiesterase-5 inhibitors found in a dietary supplement and pre-mixed bulk powders for dietary supplements using high-performance … P Zou, SSY Oh, P Hou, MY Low, HL Koh Journal of Chromatography A 1104 (1-2), 113-122, 2006 | 216 | 2006 |
| Protective effects of ginseng on neurological disorders WY Ong, T Farooqui, HL Koh, AA Farooqui, EA Ling Frontiers in aging neuroscience 7, 141694, 2015 | 211 | 2015 |
| Analysis of saponins in raw and steamed Panax notoginseng using high-performance liquid chromatography with diode array detection AJ Lau, SO Woo, HL Koh Journal of Chromatography a 1011 (1-2), 77-87, 2003 | 193 | 2003 |
| Screening of synthetic PDE-5 inhibitors and their analogues as adulterants: analytical techniques and challenges DN Patel, L Li, CL Kee, X Ge, MY Low, HL Koh Journal of pharmaceutical and biomedical analysis 87, 176-190, 2014 | 189 | 2014 |
| Antiplatelet and anticoagulant effects of Panax notoginseng: comparison of raw and steamed Panax notoginseng with Panax ginseng and Panax quinquefolium AJ Lau, DF Toh, TK Chua, YK Pang, SO Woo, HL Koh Journal of ethnopharmacology 125 (3), 380-386, 2009 | 187 | 2009 |
| Pharmacists' patterns of use, knowledge, and attitudes toward complementary and alternative medicine HL Koh, HH Teo, HL Ng The Journal of Alternative & Complementary Medicine 9 (1), 51-63, 2003 | 166 | 2003 |
| Effects of water-soluble Ganoderma lucidum polysaccharides on the immune functions of patients with advanced lung cancer Y Gao, W Tang, X Dai, H Gao, G Chen, J Ye, E Chan, HL Koh, X Li, ... Journal of medicinal food 8 (2), 159-168, 2005 | 164 | 2005 |
| A guide to medicinal plants: an illustrated, scientific and medicinal approach HL Koh, TK Chua, CH Tan World scientific, 2009 | 150 | 2009 |
| Ultra-high performance liquid chromatography/time-of-flight mass spectrometry (UHPLC/TOFMS) for time-dependent profiling of raw and steamed Panax notoginseng DF Toh, LS New, HL Koh, ECY Chan Journal of pharmaceutical and biomedical analysis 52 (1), 43-50, 2010 | 134 | 2010 |
| High-performance liquid chromatographic method with quantitative comparisons of whole chromatograms of raw and steamed Panax notoginseng AJ Lau, BH Seo, SO Woo, HL Koh Journal of Chromatography A 1057 (1-2), 141-149, 2004 | 126 | 2004 |
| Ethnobotanical survey of usage of fresh medicinal plants in Singapore YY Siew, S Zareisedehizadeh, WG Seetoh, SY Neo, CH Tan, HL Koh Journal of ethnopharmacology 155 (3), 1450-1466, 2014 | 122 | 2014 |
| Isolation and identification of thiohomosildenafil and thiosildenafil in health supplements P Zou, P Hou, SSY Oh, YM Chong, BC Bloodworth, MY Low, HL Koh Journal of pharmaceutical and biomedical analysis 47 (2), 279-284, 2008 | 101 | 2008 |
| Analysis of adulterants in a traditional herbal medicinal product using liquid chromatography–mass spectrometry–mass spectrometry AJ Lau, MJ Holmes, SO Woo, HL Koh Journal of Pharmaceutical and Biomedical Analysis 31 (2), 401-406, 2003 | 96 | 2003 |
| Chemical fingerprinting of Isatis indigotica root by RP-HPLC and hierarchical clustering analysis P Zou, Y Hong, HL Koh Journal of Pharmaceutical and Biomedical Analysis 38 (3), 514-520, 2005 | 93 | 2005 |
| Determination of indican, isatin, indirubin and indigotin in Isatis indigotica by liquid chromatography/electrospray ionization tandem mass spectrometry P Zou, HL Koh Rapid Communications in Mass Spectrometry: An International Journal Devoted …, 2007 | 88 | 2007 |
| Structural elucidation of a tadalafil analogue found as an adulterant of a herbal product P Zou, P Hou, MY Low, HL Koh Food additives and contaminants 23 (05), 446-451, 2006 | 87 | 2006 |
