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Guinea pig atria, sensitized in vitro with rabbit anti-streptolysin O, release histamine when challenged with inactive toxin and both histamine and acetylcholine when tested with the active (reduced) form. Challenge with active toxin results in a transient cholinergic depressor reaction which precedes the long-lasting augmentor effect of histamine. This biphasic response was analyzed by (1) varying the intensity of the anaphylactic phase alone, (2) by activating the toxin in the reaction system after initiating anaphylaxis by inactive toxin, and (3) by simulation of the biphasic response, using the mediators themselves. When the atrium is presented both substances simultaneously, the response to acetylcholine precedes that to histamine. The powerful atrial cholinesterase activity explains the transience of the toxic phase. The transient and oppositely directed effects of acetylcholine on the cardiac action potential always override those of histamine.

The morphology and incidence of a spontaneous solid lymphoid tumour of Xenopus laevis was studied. 180 adult tumour-bearing animals were diagnosed in the course of observations made on a large laboratory colony over a period of 4 years. The annual incidence of the tumour varied between 1.5 and 7%. The disease was more prevalent in the laboratory stock than among newly imported animals. The tumours were found to have arisen chiefly in the liver, spleen and kidneys, and metastases to almost all other organs were observed. Electron microscopic studies showed some similarities between the tumour cells and the ‘monocyte-like’ cells encountered in the normal spleen. The examination of the malignant cells in the spleen and liver so far did not reveal the presence of virus particles.

This paper presents a rational method of stressing single or many cell tubes particularly of the type encountered in wing structures. The theory has been developed for conical or cylindrical tubes of arbitrary cross-section the shape of which is maintained by a closely spaced system of diaphragms rigid in their own planes and parallel to the root section. Within the limits of the assumptions the theory is exact for right cylindrical tubes, and is applicable with adequate accuracy to cylindrical or conical tubes in which the inclination of any generator to the normal to the root plane does not exceed 10°.The analysis given unifies the theories of bending and torsion and shows that the commonly used method of separating the bending and torsion loads by means of a shear centre is in general incorrect.The formulae have been developed in such forms that attention is concentrated on the necessary corrections to the stresses as indicated by the ordinary engineers' theory. These correction terms include all effects of shear lag, diffusion, and end effects hitherto taken into account only in some very special cases.Particularly important for practical applications is the structure consisting of a number of direct stress carrying members (booms) connected by walls effective only in shear. The simplest structure of the latter type is the four-boom tube with or without nose and trailing cells, and in this case explicit formulae are given which are immediately applicable to practical calculations. Formulae are also given for the more complex case of a six-boom tube in which the two extra booms are introduced to represent more accurately the direct stress carrying capacity of the top and bottom panels between the two spars.

Diphenoxy-chlormethan wird durch thermische Spaltung von Diphenoxy-acetylchlorid nach einem verbesserten Verfahren dargestellt, und es werden die dabei entstehenden Nebenprodukte aufgeklart. Es bildet durch Umsetzung mit Trityl-natrium aber auch mit Lithium-phenyl Tetraphenoxy-athen. Durch Reaktion mit Triathylamin, Anilin und Diathylamin last sich zeigen: das Diphenoxy-chlormethan tertiare Amine unter Bildung von Ammoniumsalzen anlagert, die unter Bildung der Hydrochloride der Tertiarbasen spaltbar sind, mit primaren Aminen dagegen Amidine unter Substitution der Phenoxygruppen liefert und mit sekundaren Aminen Substitutionsprodukte, die zu Orthoameisensaure-triphenylester disproportionieren. Dieser bidet sich auf ahnliche Weise neben Ameisensaurephenylester auch aus dem Einwirkungsprodukt von Diphenoxychlormethan auf Glycinsilber. Die Salze der Diathylaminoessigsaure hingegen liefern mit Diphenoxy-chlormethan Diathylaminoessigsaurephenylester. Das Reaktionsprodukt aus Glycinsilber und Diphenoxymethyltriathyl-ammoniumchlorid ist wahrscheinlich ein „Ylid”, das durch eine STEVENSCHE Umlagerung in eine Chinomethanverbindung ubergeht.

In 3.2.1 it was indicated that ξi, ηi may be found from the appropriate co-factors of the secular equation and appear directly as functions of the geometric and elastic properties of the root cross-section. The method will be applied in 5.6.2 for the four-boom tube, in 5.7.3 for the n-boom tube, and in 5.8 for the trapezoidal tube with direct stress carrying top and bottom panels. This procedure is advantageous when it is desired to study the effect on ξ, η of varying particular parameters of the cross-section.However, when in any case the h-functions have to be obtained, it is often more expedient to determine ξ, η by one of the following procedures.

Durch Umsetzung einer Losung von Nitrosylchloroantimonat(V) (NOSbCl6) in flussigem Schwefeldioxyd mit einer Losung von Tetramethylammonium-nitroprussiat in demselben Losungsmittel wurde ein Gemisch von Dinitrosyl-nitroprussiat, (NO)2 [Fe(NO)(CN)5], und Nitrosyl-tetramethylammonium-nitroprussiat, N(CH3)4 (NO) [Fe(NO)(CN)5] erhalten. Das Produkt stellt ein orangefarbenes, sehr hygroskopisches Pulver dar, welches alle Eigenschaften einer salzartigen Nitrosylverbindung besitzt.

L'infectivite des extraits tissulaires de la «tumeur lymphoide» deXenopus laevis diminue apres traitement a l'ether, au chloroforme, et a la temperature de 56 °C, tandis qu'elle reste inchangee apres traitement au pH acide. Ces caracteristiques ne permettent pas de placer l'agent tumoral parmi les virus des animaux connus a l'heure actuelle.

Investigations were carried out in rats to determine the relative roles of kidney and bone in the regulation of plasma calcium by parathyroid hormone (PTH). The effects of endogenous PTH were studied by parathyroid ablation. Parathyroid glands were removed by thyroparathyroidectomy (TPTX) since parathyroidectomy appears to release calcitonin and thyroidectomy itself does not alter plasma calcium levels. Changes in plasma calcium, urinary calcium and urinary hydroxyproline were determined 3 hr or 24 hr after TPTX in rats of varying ages and in animals fed a calcium-deficient diet for 30 days to enhance PTH secretion and bone turnover. The following observations were made. 1)Plasma calcium but not hydroxyproline decreased 3 hr after TPTX. 2) The degree of hypocalcemia was inversely related to age. 3) By 24 hr, urinary hydroxyproline had decreased and plasma calcium fallen further. 4) Plasma calcium and urinary hydroxyprolinedecreased immediately in immature rats and rats fed a calcium-deficient diet. 5) TPT...

La «tumeur lymphoide» deXenopus laevis est transmissible par des filtrats acellulaires ainsi que par injection des surnageants de centrifugation des extraits de tissus cancereux a des vitesses qui sedimentent les virus connus jusqu'a present.