N-nitroso-compounds form an important class of carcinogenic chemicals which may be of environmental importance (Druckrey et al. , 1967; Magee et al. , 1976; IARC, 1978). The mechanism by which these carcinogens initiate neoplastic growth is not well understood but there is substantial evidence favoring the hypothesis that the simple dialkylnitrosamines and alkylnitrosamides act by means of their conversion to al- kylating agents. Alkylating species are generated from the nitrosamines by metabolic activation and from the nitrosamides by chemical decomposition at physiological pH. It is widely believed that DNA is the critical alkylation target. Alkylation takes place at at least 12 sites within the DNA molecule (Lawley, 1976; Singer, 1976; Pegg, 1977a). Al- though alkylation at the 7-position of guanine is the most extensive reaction with the DNA bases and provides a reliable measurement of the degree of interaction with the carcinogen (Swann and Magee, 1968, 1971), recent experiments have suggested that alkylation of oxygen atoms may be the critical reaction (Goth and Rajewsky, 1974; Margison and Kleihues, 1975; Nicoll et aI. , 1975; Pegg, 1977a). These laboratories have observed a correlation between the production and persistence of 06-alkyl- guanine and the occurrence oftumors in a variety of organs of rodents exposed to N-ni- troso-carcinogens. It has, therefore, been suggested that the ability of tissues to catalyze the removal of 06-alkylguanine from DNA may provide a protective mechanism against carcinogenesis.

A comprehensive yet easily accessible clinical cardiology reference for practicing veterinarians, residents, interns, and veterinary students. This edition covers equine cardiology as well as small animal. Reflects the authors' extensive clinical and teaching experience in veterinary cardiology over the past four decades, as well as a review of wide-ranging literature. Clearly written, well-integrated across chapters, and richly illustrated. Includes some advanced topics to provide a useful perspective regarding the current scope of veterinary cardiology. The extensive use of visual images is a core feature of this book- over 150 new images are included, while others have been brought forward from the first edition. Extensive bibliography lists, as well as a number of supplemental videos, are available on-line for the interested reader. These are especially useful for learning about modalities such as echocardiography.

Title: Notes on political economy as applicable to the United States.Author: Nathaniel A WarePublisher: Gale, Sabin Americana Description: Based on Joseph Sabin's famed bibliography, Bibliotheca Americana, Sabin Americana, 1500--1926 contains a collection of books, pamphlets, serials and other works about the Americas, from the time of their discovery to the early 1900s. Sabin Americana is rich in original accounts of discovery and exploration, pioneering and westward expansion, the U.S. Civil War and other military actions, Native Americans, slavery and abolition, religious history and more.Sabin Americana offers an up-close perspective on life in the western hemisphere, encompassing the arrival of the Europeans on the shores of North America in the late 15th century to the first decades of the 20th century. Covering a span of over 400 years in North, Central and South America as well as the Caribbean, this collection highlights the society, politics, religious beliefs, culture, contemporary opinions and momentous events of the time. It provides access to documents from an assortment of genres, sermons, political tracts, newspapers, books, pamphlets, maps, legislation, literature and more.Now for the first time, these high-quality digital scans of original works are available via print-on-demand, making them readily accessible to libraries, students, independent scholars, and readers of all ages.++++The below data was compiled from various identification fields in the bibliographic record of this title. This data is provided as an additional tool in helping to insure edition identification: ++++SourceLibrary: Huntington LibraryDocumentID: SABCP01053500CollectionID: CTRG93-B524PublicationDate: 18440101SourceBibCitation: Selected Americana from Sabin's Dictionary of books relating to AmericaNotes: Collation: viii, 304 p.; 23 cm

This scarce antiquarian book is a selection from Kessinger Publishing's Legacy Reprint Series. Due to its age, it may contain imperfections such as marks, notations, marginalia and flawed pages. Because we believe this work is culturally important, we have made it available as part of our commitment to protecting, preserving, and promoting the world's literature. Kessinger Publishing is the place to find hundreds of thousands of rare and hard-to-find books with something of interest for everyone

Kessinger Publishing is the place to find hundreds of thousands of rare and hard-to-find books with something of interest for everyone!

Kessinger Publishing is the place to find hundreds of thousands of rare and hard-to-find books with something of interest for everyone!

Kessinger Publishing is the place to find hundreds of thousands of rare and hard-to-find books with something of interest for everyone!