SKIN PENETRATION 631 (53) (54) (55) (56) (57) (34) Bettlcy, F. R., and Donoghue, E., Effect of soap on the diffusion of water through isolated human epidermis, Nature, 185, 17 (1960). (35) Brown, J., Winkehnann, R. K., and Wolff, K., Langerhans cells in vitiligo: A quanti- tative study, J. Invest. Dermatol., 49, 386 (1967). (36) Smith, J. G., Fischer, R. W., and Blank, H., The epidermal barrier. A comparison between scrotal and abdominal skin, Ibid., 36, 337 (1961). (37) Cronin, E., and Stoughton, R. B., Percutaneous absorption: regional variations and the effect of hydration and epidermal stripping, Brit. J. Dermatol., 74, 265 (1962). (38) Feldmann, R. J., and Maibach, H. I., Regional variation in percutaneous penetration of •C-cortisol in man, ]. Invest. Dermatol., 48, 181 (1967). (39) Tregear, R. T., Relative penetrability of hair follicles and epidermis, J. Physiol., 156, 307 (1961). (40) Winkelmann, R. K., The reIationship of the structure of the epidermis to percutaneous absorption, Brit. ]. Dermatol., 81, Suppl. 4, 11 (I969). (41) Marzulli, F. N., Brown, D. W. C., and Maibach, H. I., Techniques for studying skin penetration, Toxicol. Appl. Pharmacol., Suppl. 3, 76 (I969). (42) Wolff, K., and Winkelmann, R. K., in Montagna, W., and Hu, F., Advances in Biology of Skin, Pergamon Press, Oxford, 1967, p. 1935. (43) Steigleder, G. K., Aminopeptidasen--aktivitat auf der hautoberfl•ichc, Klin. Wochen,chr., 40, 1154 (1962). (44) Vickers, C. F. H., Existence of reservoir in the stratum corneum, Arch. Dermatol., 88, 2O (1963). (45) McKenzie, A. W., and Stoughton, R. B., Method for comparing percutaneous absorp- tion of steroids, Ibid., 86, 608 (1962). (46) Hall-Smith, S. P., "Polythene" coverings in dermatological treatment, Brit. Med. J., 2, 1233 (1962). (47) Sulzberger, M. B., and Witten, V. H., Thin pliable plastic films in topical dermatologic therapy, Arch. Dermatol., 84, 1027 (1961). (48) Witten, V. H., Stein, S. J., and Michaelides, P., Use of thin pliable film in selected dermatoses, Ibid., 87, 458 (1963). (49) Wurster, D. E., and Kramer, S. F., Investigation of some factors influencing percuta- neous absorption, J. Pharm. Sci., 50, 288 (1961). (50) Fritsch, W. F., and Stoughton, R. B., The effect of temperature and humidity on the penetration of C • acetylsalicylic acid in excised human skin, J. Invest. Dermatol., 82• 24 (1960). (51) Shelmire, J. B., Factors determining the skin-drug-vehicle relationship, Arch. Dermatol., 82, 24 (1960). (52) Allenby, A. C., Fletcher, J., Schock, C., and Tees, T. F. S., The effect of heat, pH and organic solvents on electrical impedence and permeability of excised human skin, Brit. J. Dermatol., 81, Suppl. 4, 31 (1969). Wagner, J. G., Biopharmaceutics: absorption aspects, I. Pharm. Sci., 50, 359 (1961). Schutz, E., Der einfluss von polyathyleneglykol 400 auf die percutane resorption yon wirkstoffen, Exp. Patrol. Pharmakol., 232, 237 (1957). Maibach, H. I., and Feldmann, R. J., Effect of applied concentration on percutaneous absorption in man, ]. Invest. Dermatol., 52, 382 (1969). Christie, G. A., and Moore-Robinson, M., Vehicle assessment--methodology and re- sults, Brit. ]. Dermatol., 82, Suppl. 6, 93 (1970). Skog, E., and Wahlberg, J. E., A comparative investigation of the percutaneous ab- sorption of metal compounds in the guinea pig by means of the radioactive isotopes: mCr, •SCo, •Zn, •XøAg, •Cd, •Hg, J. Invest. Dermatol., 43, 187 (1964).

632 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS (58) Elfbaum, S. G., and Laden, K., The effect of dimethyl sulfoxide on percutaneous ab- sorption: A mechanistic study, Part II, J. Soc. Cosmet. Chem., 19• 163 (1968). (59) Dugard, P. H., and Embery, G., The influence of dimethyl sulfoxide on the percuta- neous migration of potassium butyl (mS) sulphate, potassium methyl (3•S) sulphate, Brit. J. Dermatol., 81, Suppl. 4, 69 (1969). (60) Katz, M., and Shaikh, Z. I., Percutaneous corticosteroid absorption correlated to parti- tion coefficient, J. Pharm. Sci., 54, 591 (1965). (61) Blank, I. H., Transport across the stratum corneum, Toxicol. Appl. Pharmacol., Suppl. 3, 23 (1909). (62) Busse, M. J., Hunt, P., Lees, K. A., Maggs, P. N. D., and McCarthy, T. M., Release of betamethasone derivatives from •ointments. In vivo and in vitro studies, Brit. ]. Dermatol., 81, Suppl. 4, 103 (1969). (63) Minato, A., Fukuzawa, H., Seiju, H., and Yasuko, K., Radioisotopic studies on per- cutaneous absorption. I. Absorption of water-soluble substances from hydrophilic and absorption ointments through mouse skin, Chem. Pharm. Bull. (Tokyo), 15, 470 (1967). (64) Treherne, J. E., The permeability of skin to some nonelectrolytes, J. Physiol., 133, 171 (1956). (65) Stoughton, R. B., Clendenning, W. E., and Kruse, D., Percutaneous absorption of nicotinic acid derivatives, J. Invest. Dermatol., 35, 337 (1960). (66) Cronin, E., and Stoughton, R. B., Nicotinic acid and ethyl nicotinate in excised human skin, Arch. Dermatol., 87, 445 (1963). (67) McKenzie, A. W., Percutaneous absorption of steroids, Ibid., 86, 611 (1962). (68) McKenzie, A. W., and Aitkinson, R. M., Topical activities of betamethasone esters in man, Ibid., 89, 741 (1964). (69) Poulsen, B. J., Young, E., Coquilla, V., and Katz, M., The effect of topical vehicle composition on the in vitro release of fiuocinolone acetonide and its acetate ester, J. Pharm. Sci., 57, 928 (1968). (70) Coldman, M. F., Poulsen, B. J., and Higuchi, T., Enhancement of percutaneous ab- sorption by the use of volatile:non-volatile systems as vehicles, Ibid., 58, 1098 (1969). (71) Dempski, R. E., Portnoff, J. B., and Wase, A. W., In vitro release and in vivo penetra- tion studies of a topical steroid from nonaqueous vehicles, Ibid., 58, 579 (1969). (72) Tregear, R. T., Physical Functions of the Shin, Academic Press, New York, 1966. (73) Sprott, W. E., Surfactants and percutaneous absorption, Trans. St. John's Hosp. Dermatol. Soc. (London), 51, 186 (1965). (74) Tregear, R. T., The permeability of skin to albumin, dextrans and polyvinyl pyr- rolidone, J. Invest. Dermatol., 46, 24 (1966). (75) Scheuplein, R. J., Blank, I. H., and MacFarlane, D. J., Percutaneous absorption of steroids, Ibid., 52, 63 (1969). (76) Kappert, A., •ber einige wirkungen yon DMSO bei percutaner anwendung, Schweiz. Med. Wochenschr., 98, 1829 (1968). (77) Barrett, C. W., Hadgraft, J. W., Caron, G. A., and Sarkany, I., The effect of particle size and vehicle on the percutaneous absorption of fiuocinolone acetonide, Brit. J. Derrnatol., 77, 576 (1965). (78) Barrett, C. W., Hadgraft, J. W., and Sarkany, I., A method for applying standard quantities of ointment to the skin, Ibid., 76, 479 (1964). (79) Barrett, C. W., Skin penetration, J. Soc. Cosmet. Chem., 20, 487 (1969). (80) Barrett, C. W., Hadgraft, J. W., and Sarkany, I., The influences of vehicles on skin penetration, J. Pharm. Pharmacol., 16, Suppl. 104T (1964). (81) Higuchi, T., Rate of release of medicaments from ointment bases containing drugs in suspension, .]. Pharrn. Sci., 50, 874 (1961).