The effect of temperature upon the exchange rates between intra- and extracellular potassium in chick embryo muscle was determined by the use of radioactive potassium. The temperature coefficient of at least four-fifths of the cell potassium is large. At temperatures below 15 degrees C., potassium is lost from the cell and is regained on warming. The results suggest the possibility that 20 per ...

In the venous clip model specific cardiac malformations are induced in the chick embryo by obstructing the right lateral vitelline vein with a microclip. Clipping alters venous return and intracardiac laminar blood flow patterns, with secondary effects on the mechanical load of the embryonic myocardium. We investigated the instantaneous effects of clipping the right lateral vitelline vein on he...

Somerson, Norman L. (National Institute of Allergy and Infectious Diseases, Bethesda, Md.), and M. K. Cook. Suppression of Rous sarcoma virus growth in tissue cultures by Mycoplasma orale. J. Bacteriol. 90:534-540. 1965.-An agent which produced cell destruction in human diploid and chick-embryo fibroblasts was isolated from WI-26 strain of human diploid fibroblasts and shown to be a mycoplasma....

1. An artificial air space was made in the narrow end of the pipped egg by separating the shell membranes from the shell. The respiratory and hatching movements of the embryo set up pressure changes within the artificial air space and these were recorded up until the moment when the chick emerged from the shell. 3. Random movements appeared to be inhibited during the period of hatching. 4. The ...

1. A strain of neurovaccine virus was cultivated in a medium consisting of minced chick embryo suspended in Tyrode's solution. 2. The virus upon cultivation apparently lost none of its essential characteristics. 3. The culture virus can be preserved and stored for long periods of time. Furthermore, the preserved virus can be used to initiate fresh cultures.

BACKGROUND Ischemia is a pathophysiological condition due to blockade in blood supply to a specific tissue thus damaging the physiological activity of the tissue. Different in vivo models are presently available to study ischemia in heart and other tissues. However, no ex vivo ischemia model has been available to date for routine ischemia research and for faster screening of anti-ischemia drugs...

It is extremely difficult, if not impossible, to reconcile the conflicting claims of those who have treated different cells and tissues with exogenous RNA. Some authors (e.g. Niu, Cordova & Niu, 1961 ; Niu, Cordova & Radbill, 1962) maintain that RNA extracts alter the course of cell differentiation to conform in morphological terms to the source of the RNA; in the same vein, Amos, Askonas & Soe...