The effects of diltiazem on Periplaneta americana

The effects of the calcium antagonist diltiazem on nerve and muscle in the cockroach Periplaneta americana were examined. Diltiazem was observed to inhibit myogenic and glutamate-induced contractions of the visceral muscle while having either a potentiating, an inhibiting or a biphasic effect against proctolin-induced contractions. Against the isolated nervous system, diltiazem induced an increase in spontaneous discharge activity, followed by nerve block. Injection of diltiazem into cockroaches produced behavioral and toxic effects.     

United Kingdom: The Corporate Strategy for 1989 of the Medical Research Council (MRC)

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United Kingdom: The Corporate Strategy for 1989 of the Medical Research Council (MRC)     

Using computational models to discover and understand mechanisms

Areas of biology such as cell and molecular biology have been dominated by research directed at constructing mechanistic explanations that identify parts and operations that when organized appropriately are responsible for the various phenomena they investigate. Increasingly the mechanisms hypothesized involve non-sequential organization of non-linear operations and so exceed the ability of researchers to mentally rehearse their behavior. Accordingly, scientists rely on tools of computational modeling and dynamical systems theory in advancing dynamic mechanistic explanations. Using circadian rhythm research as an exemplar, this paper explores the variety of roles computational modeling is playing. They serve not just to determine whether the mechanism will produce the desired behavior, but in the discovery process of hypothesizing mechanisms and in understanding why proposed mechanisms behave as they do.     

Cytoskeleton–membrane interactions in membrane raft structure

Cell membranes are structurally heterogeneous, composed of discrete domains with unique physical and biological properties. Membrane domains can form through a number of mechanisms involving lipid–lipid and protein–lipid interactions. One type of membrane domain is the cholesterol-dependent membrane raft. How rafts form remains a current topic in membrane biology. We review here evidence of structuring of rafts by the cortical actin cytoskeleton. This includes evidence that the actin cytoskeleton associates with rafts, and that many of the structural and functional properties of rafts require an intact actin cytoskeleton. We discuss the mechanisms of the actin-dependent raft organization, and the properties of the actin cytoskeleton in regulating raft-associated signaling events. We end with a discussion of membrane rafts and the actin cytoskeleton in T cell activation, which function synergistically to initiate the adaptive immune response.     

A GNERAL BIJECTIVE ALGORITHM FOR INCREASING TREES

1.IntroductionTheenumerationoftreesisstillanajctiveresearchareaincombinatoricsdespiteitsrichhistory3andvariouskindsoftreescontinuetoemergeincombinatorics,computerscience,computationalbiologyaswellasinmathematicalphysics.Themainconcernofthispaperiswithabijectiveapproachtoincreasingtrees,whichismotivatedbyarecentworkofGessel,SaganandYehontheenumerationofrootedtreesbythenetnumberofinversions.Inthesearchforasign-reversinginvolutionasacombinatorialillterpretationofthecancellationinvolvedintheLagr…     

基因组研究的数据库

与基因组有关的数据库已经成为科学领域的重要部分。随着相关生物数据的容量和复杂性的提高，这些数据库所起的作用将增加。我们还没有完成基因组计划和发展这些数据库，不言而喻，既要十分详尽，又要简明地建设数据库。后者特别需要，使文摘式数据库更易于普及。基因组数据库是人所共知的基因组计划的公众窗口。基因组计划成功或失败依赖于所产生的数据的获取和利用。而且，高度发达的科学创造了大量的组织得很好的数据。随着这个大量增加的生物数据需要传递，要求各类文摘式数据库。生物学和数据库技术的特性，是要定期回顾分析，以确定生…