SAR focuses on the quantitative structure-activity relationship (QSAR) of the disposition and activities of various pharmacological groups - the first systematic approach for linking different side effects of drugs to their molecular structure and physiochemical properties. This unique monograph describes the application of molecular modification to the practical improvement of therapeutic agents; depicts the quantitative measurement of biological activity as it relates to QSAR; provides essential guidance on selecting suitable mathematical models, defining appropriate parameters in correlation studies and anticipating potential side effects during the tedious drug development process.

Der vorliegende 48. Band der Reihe "Fortschritte der Arzneimittelfor- schung" enthalt acht Beitrage, die wiederum von anerkannten Forschern verfasst wurden. Ausserdem sind auch in diesem Band ein Stichwortver- zeichnis des Bandes sowie ein Autoren-und Titelverzeichnis und ein Titel- verzeichnis aller 48 Bande enthalten. Der Leser hat dadurch die Mog- lichkeit, nicht nur den vorliegenden Band zu konsultieren, sondern auch alle bisher erschienenen Bande quasi als enzyklopadisches N achschla- gewerk zu benutzen. Da alle Beitrage umfangreiche Literaturnachweise enthalten, ist die Moglichkeit des Zugriffes auf Original-Publikationen gegeben, was dem aktiven Forscher besonders wichtig ist und seinen eige- nen Arbeiten Impulse geben kann. Die Artikel des 48. Bandes behandeln neue Entwicklungen der Genetik, der enzymatischen Herstellung von komplexen Peptiden und bringen die neuesten Erkenntnisse der Apoptose unserem Verstandnis naher. Immun- therapie bei Hirnerkrankungen und psychischen Storungen, der Einsatz vonNaturproduktenzur Vorbeugung von Krebserkrankungen, das beun- ruhigende Anwachsen der Arzneimittelresistenz, die Mannigfaltigkeit der Dopamin-Rezeptor-Wirkung und die faszinierende Darstellung einer grosseren Gruppe von neuartigen Nukleosiden als Arzneimittel runden den vorliegenden Band der "Fortschritte der Arzneimittelforschung" ab und bieten dem Leser viel Neuartiges und Interessantes.

Progress in Drug Research is a prestigious book series which provides extensive expert-written reviews on a wide spectrum of highly topical areas in current pharmaceutical and pharmacological research. It serves as an important source of information for researchers concerned with drug research and all those who need to keep abreast of the many recent developments in the quest for new and better medicines.

Hepatitis C virus (HCV) was first identified in 1989 as the etiologic agent of non-A, non-B hepatitis [1] and is currently recognized as the leading cause of chronic liver disease worldwide. In contrast to hepatitis B virus infection, in which only about 5% of adult infections become chronic, more than 80% of HCV-infected patients develop chronic hepatitis. Moreover, 20-50% of those persistently infected with HCV will develop liver cirrhosis and hepatocellu lar carcinoma (HCC) [2]. It is estimated that there are 10,000 deaths in the USA per year due to chronic liver failure or HCC [3]. In addition, HCV dis 25-50% of all liver transplants in US centers, and the ease is responsible for recurrence of HCV infection following liver transplantation is universal [4]. Typically, HCV disease emerges after a 10-20 year period during which symp toms, if they exist at all, are mild and non-specific. Although the prevalence varies greatly among different countries, it has been estimated that up to 170 million people (3% of the world's population), are infected with HCV [5]. A recent study in the USA found that 65% of all HCV-infected persons are 30 to 49 years old [6].

Progress in Drug Research is a prestigious book series which provides extensive expert-written reviews on a wide spectrum of highly topical areas in current pharmaceutical and pharmacological research. It serves as an important source of information for researchers concerned with drug research and all those who need to keep abreast of the many recent developments in the quest for new and better medicines.