[1] [1] Marshall M M, Naumovitz D, Ortega Y, et al. Waterborne protozoan pathogens[J]. Clinical Microbiology Reviews, 1997, 10(1): 67?85.

[2] [2] Savioli L, Smith H, Thompson A. Giardia and Cryptosporidium join the ‘Neglected Diseases Initiative’[J]. Trends in Parasitology, 2006, 22(5): 203?208.

[3] [3] EPA. Technologies and techniques for early warning systems to monitor and evaluate drinking water quality: a state-of-the-art review[R]. Washington, DC, USA: Environmental Protection Agency, 2005.

[4] [4] Hoebe R A, van Oven C H, Gadella Jr T W J, et al. Controlled light-exposure microscopy reduces photobleaching and phototoxicity in fluorescence live-cell imaging[J]. Nature Biotechnology, 2007, 25(2): 249?253.

[5] [5] Guy R A, Payment P, Krull U J, et al. Real-time PCR for quantification of giardia and Cryptosporidium in environmental water samples and sewage[J]. Applied and Environmental Microbiology, 2003, 69(9): 5178?5185.

[6] [6] Sadaka H A, Gaafar M R, Mady R F, et al. Evaluation of ImmunoCard STAT test and ELISA versus light microscopy in diagnosis of giardiasis and cryptosporidiosis[J]. Parasitology Research, 2015, 114(8): 2853?2863.

[7] [7] Park Y K, Depeursinge C, Popescu G. Quantitative phase imaging in biomedicine[J]. Nature Photonics, 2018, 12(10): 578?589.

[8] [8] Ikeda T, Popescu G, Dasari R R, et al. Hilbert phase microscopy for investigating fast dynamics in transparent systems[J]. Optics Letters, 2005, 30(10): 1165?1167.

[9] [9] Popescu G, Deflores L P, Vaughan J C, et al. Fourier phase microscopy for investigation of biological structures and dynamics[J]. Optics Letters, 2004, 29(21): 2503?2505.

[10] [10] Paganin D, Nugent K A. Noninterferometric phase imaging with partially coherent light[J]. Physical Review Letters, 1998, 80(12): 2586?2589.

[11] [11] Shaked N T, Zhu Y Z, Rinehart M T, et al. Two-step-only phase-shifting interferometry with optimized detector bandwidth for microscopy of live cells[J]. Optics Express, 2009, 17(18): 15585?15591.

[12] [12] Popescu G, Ikeda T, Dasari R R, et al. Diffraction phase microscopy for quantifying cell structure and dynamics[J]. Optics Letters, 2006, 31(6): 775?777.

[13] [13] Park K, Millet L J, Kim N, et al. Measurement of adherent cell mass and growth[J]. Proceedings of the National Academy of Sciences of the United States of America, 2010, 107(48): 20691?20696.

[14] [14] Eldridge W J, Sheinfeld A, Rinehart M T, et al. Imaging deformation of adherent cells due to shear stress using quantitative phase imaging[J]. Optics Letters, 2016, 41(2): 352?355.

[15] [15] Tian P, Yan W, Li F X, et al. Biology microscopy using well-distributed sphere digital in-line holography[J]. Opto-Electronic Engineering, 2019, 46(1): 180110.

[16] [16] Xiang W D, Yang P, Wang S, et al. Underwater image enhancement based on red channel weighted compensation and gamma correction model[J]. Opto-Electronic Advances, 2018, 1(10): 180024.

[17] [17] Goldstein R M, Zebker H A, Werner C L. Satellite radar interferometry: two-dimensional phase unwrapping[J]. Radio Science, 1988, 23(4): 713?720.

[18] [18] GE Healthcare. Ficoll PM70, Ficoll PM400, Data File 18–1158-27 AB[EB/OL]. https://cdn.gelifesciences.com/dmm3- bwsv3/AssetStream.aspx?mediaformatid=10061&destinationid=10016&assetid=12817.

[19] [19] Low F C, Wiemken A. Fractionation of Hevea brasiliensis latex on ficoll density gradients[J]. Phytochemistry, 1984, 23(4): 747?750.

[20] [20] Zheng C, Zhou R J, Kuang C F, et al. Digital micromirror device-based common-path quantitative phase imaging[J]. Optics Letters, 2017, 42(7): 1448?1451.

[21] [21] Thompson R C A. The zoonotic significance and molecular epidemiology of Giardia and giardiasis[J]. Veterinary Parasitology, 2004, 126(1?2): 15?35.

[22] [22] Smith H V, Nichols R A B. Cryptosporidium: detection in water and food[J]. Experimental Parasitology, 2010, 124(1): 61?79.

[23] [23] Aknoun S, Savatier J, Bon P, et al. Living cell dry mass measurement using quantitative phase imaging with quadriwave lateral shearing interferometry: an accuracy and sensitivity discussion[J]. Journal of Biomedical Optics, 2015, 20(12): 126009.