There are over one hundred species of lactic acid bacteria. They are best known for their role in fermentation, especially in dairy products like yoghurt and sour milk. Ljungh and Wadstr繹m, (medicine, Lund University, Sweden) present essays that cover the history of lactobacillus study, the genome mapping of the several forms and methods of examination. These are followed by reports on clinical studies of the use of lactobacillus in treating conditions. These range from administering them as probiotics to counteract negative reactions to antibiotics, easing digestive tract problems, improving the immune system and even helping to prevent cancer. The articles are intended for medical professionals, but the conclusions are exciting enough to convince anyone to eat more yogurt. Distributed in the US by ISBS. Annotation 穢2009 Book News, Inc., Portland, OR (booknews.com)