The observation in the 1950s that nitrogen mustard and other toxic chemicals could induce antitumor responses in patients with refractory lymphoma initiated a massive search for active chemotherapeutic agents. The initial observations stimulated a search for new chemotherapeutic agents which might have increased antitumor activity with less toxicity for normal tissues. To aid in the search for these new chemicals and to attempt to distinguish among the many toxic chemicals which might be candidates for clinical studies, the National Cancer Institute, the pharmaceutical industry, and the cancer research laboratories of most Western nations developed systems for "screening" drugs for antitumor activity. Perhaps the most extensive screening program was established by the National Cancer Institute (1). This screening program has evolved over the last two decades, an evolution which has been repeatedly reviewed (2-5). Various screening programs in use have examined over 500,000 compounds as potential anticancer agents. From these, there are now approximately forty anticancer drugs in clinical use. The utiliy of these compounds and their toxicities have been reviewed on many occasions. It is now apparent that more active and less toxic anticancer drugs are needed. It is also clear that the current screening programs are identifying compounds with similar levels of activity and with continuing moderate to severe toxicity (6).

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We first started out as ?The Paperback Exchange,? a chain of physical bookstores where we would part exchange your beloved books for new stories to transport you to faraway places. However, as shopping started to evolve to online shops and marketplaces, we bid our stores goodbye to become ?PBShop.? This transition has only allowed us to blossom as we now ship thousands of titles to book lovers across the globe. We pride ourselves in being a community of local book lovers which allows our passion and devotion to shine in everything we do. In 2020 we not only celebrated our 20th birthday but our 1st birthday as being completely employee owned after becoming an E.O.T in September 2019. We are proud to be different and embrace standing apart on a book mountain by working from a virtual inventory which allows us to provide thousands of books that may be difficult to get for your bookshelf or your studies. Working with a number of different suppliers allows us to explore other avenues such as puzzles, sheet music and even stationery so we really do have something for everyone. Life is about being versatile in all realms of existence. If this is your first visit or you are a returning customer, we would like to welcome you to the PBShop family, for there is no friend as loyal as a book. We are a company who put our customers at the centre of everything we do as we understand the importance of reading because once you learn to read, you will forever be free. There are a whole lot of things in this world of ours that we are yet to explore, which is why we will forever inspire curious minds.

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Pbshop.co.uk Ltd
Unit 22 Horcott Industrial Estate, Horcott Road, Fairford, GL7 4BX, United Kingdom

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We ask all customers to contact us for authorisation should they wish to return their order. Orders returned without authorisation may not be credited.
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