Cytosolic calcium in platelet activation

Experiments with permeabilised platelets, and with intact platelets loaded with fluorescent Ca²⁺-indicators, over the past several years have greatly extended our knowledge and understanding of cytosolic Ca²⁺ as a platelet activator and its interactions with other cytosolic regulators. This article outlines insights, gained from the use of the fluorescent dyes, into maintenance and restoration of basal [Ca²⁺]_i, mechanisms of receptor-mediated Ca²⁺-mobilisation and quantitation of [Ca²⁺]_i/response relations in intact human platelets.     

The material theory of induction and the epistemology of thought experiments

John D. Norton is responsible for a number of influential views in contemporary philosophy of science. This paper will discuss two of them. The material theory of induction claims that inductive arguments are ultimately justified by their material features, not their formal features. Thus, while a deductive argument can be valid irrespective of the content of the propositions that make up the argument, an inductive argument about, say, apples, will be justified (or not) depending on facts about apples. The argument view of thought experiments claims that thought experiments are arguments, and that they function epistemically however arguments do. These two views have generated a great deal of discussion, although there hasn't been much written about their combination. I argue that despite some interesting harmonies, there is a serious tension between them. I consider several options for easing this tension, before suggesting a set of changes to the argument view that I take to be consistent with Norton's fundamental philosophical commitments, and which retain what seems intuitively correct about the argument view. These changes require that we move away from a unitary epistemology of thought experiments and towards a more pluralist position.     

Topochemical approach to the structure-activity relation. Retroenantio-Gly5,10-gramicidin S

, . , -Gly^5,10- , Gly^5,10- .     

Nachweis vonn-Butylamin in Äpfeln

Summary n-Butylamine, a new biogenic amine could be identified in apples by means of paper chromatography and micro-cristallography.     

Anti-arrhythmic properties of 1,5-dimorpholino-3-(1-Naphthyl)-pentane: DA 1686

Riassunto Il DA 1686, corrispondente al 1,5-dimorfolino-3-(1-naftil) pentano, è un derivato della naftalina ad attività antiaritmica come risulta dalle prove in vitro (orecchiette isolate di cavia) e in vivo (cani, conigli, cavie e ratti). Il composto è ben assorbito dopo somministrazione orale e viene escreto nelle urine non metabolizzato.     

Light sensitivity of melanophores in neural crest explants

Résumé Les mélanophores de la crête neurale de divers amphibiens isolés in vitro se sont montrés sensibles à la lumière. A la lumière normale, ils s'étendent, mais se contractent rapidement dans l'obscurité. Cette sensibilité intrinsèque pourrait renforcer la réaction qui produit la décoloration du corps chez les larves, mais n'en est pas la cause principale.     

Organic minerals. Picene and chrysene as constituents of the mineral curtisite (Idrialite)

Zusammenfassung Das massive organische Mineral Curtisite (Idrialite) besteht aus Picen, Chrysen und, wie aus den Massenspektren der rohen Proben zu entnehmen ist, deren Methyl-homologen.

---

---

Contribution from the Departments of Chemistry (No. 2078) and Geology, University of California, Los Angeles.     

Teratogenic effects of the amino acid leucine in the chicken

Zusammenfassung Leucin wurde in einer Dosis von 0,2 ml einer 1%igen Lösung im Amnion von 9 Tage bebrüteten Hühnereiern injiziert. Morphologische Anomalien mit abnormen Funktionen, meistens in den Beinen und der Nackenregion, wurden beobachtet, während Röntgen-Aufnahmen Stellungsanomalien in Gelenken der Extremitäten und der Halswirbel zeigten.

---

---

This work was aided by grants from Sigrid Juselius Foundation.     

Effect of lidoflazine on norepinephrine,angiotensin and serotonin responses in isolated smooth muscle preparations

Résumé Les effets de la lidoflazine ont été étudiés sur les bandelettes aortiques isolées du lapin et les bandelettes gastriques isolées du rat. La lidoflazine antagonise significativement la sérotonine sur ces 2 préparations sans altérer leurs réponses à l'angiotensine et à la noradrénaline.