41,221 research outputs found
Improved universal electrical connector
Universal electrical connector for use with various types of electric cable, inserts, and pin styles is described. Connector may be used over variety of environmental conditions. Details of construction are discussed. Illustrations of connector are included
Packaging concept for LSI beam lead integrated circuits
Development of packaging system for mounting beam lead integrated chip circuit on lead frame is discussed. Process for fabricating large scale integration circuits is described. Diagrams illustrating method of construction are included
Experimental approaches to understanding the role of protein phosphorylation in the regulation of neuronal function
Studies by Earl Sutherland and his colleagues on hormonal regulation of the breakdown of glycogen in liver resulted in the discovery that the first step in the action of many hormones is to increase the synthesis of cAMP by activating adenylate cyclase (Raft et al 1957, Sutherland & Rall 1958, Robison et al 1968). It was later established that cAMP exerts its effects by stimulating protein kinases that catalyze the phosphorylation of specific functional proteins and thereby regulate their activity (Walsh et al 1968, Kuo & Greengard 1969, Krebs & Beavo 1979). The discovery that the brain contains a high concentration of cAMP-dependent protein kinase led to the proposal that protein phosphorylation might play an important role in regulation of neuronal properties by neurotransmitters and neurohormones (Miyamoto et al 1969). In particular, it seemed that protein phosphorylation, which usually takes place on a time scale of hundreds of milliseconds or longer, might be a mechanism underlying relatively long-lasting changes in neuronal properties such as "slow" changes in post-synaptic potentials (McAfee & Greengard 1972), changes in the rate of transmitter synthesis (Morgenroth et al 1975), or changes in gene expression (Klein & Berg 1970). The biochemists and neurobiologists who took up the study of brain protein phosphorylation hoped to gain insight into some of the mechanisms underlying changes in neuronal excitability and synaptic efficacy and also, perhaps, into processes that govern the development of various neuronal types during the formation of the nervous system. This line of research was bolstered by the findings that the brain contains not only high concentrations of protein kinases, but also protein phosphatases, adenylate cyclase, and phosphodiesterase (Greengard 1976), and also by the discovery that several neurotransmitters stimulate the synthesis of second messengers such as cyclic AMP and cyclic GMP by binding to specific receptors on the surfaces of neurons (for reviews see Nathanson 1977, Greengard 1981)
Medical Science and the Law
There are those who say that the earliest physician was the priest, just as the earliest judge was the ruler who uttered the divine command and was king and priest combined. Modern scholarship warns us to swallow with a grain of salt these sweeping generalities, yet they have at least a core of truth. Our profession - yours and mine - medicine and law have divided with the years, yet they were not far apart at the beginning
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