A simple one-step procedure for staining the nucleolus organizer regions

Summary A simple silver staining technique for routine use is described by which the nucleolus organizer regions of mammalian chromosomes, including those of mouse chromosomes, are stained selectively.Acknowledgment. We would like to thank Prof. Dr K. Sperling for critical and helpful discussion.     

A new substrate for cultures of dissociated primary rat brain

Different substrates were used to coat plastic petri dishes for the cultivation of dissociated fetal rat brain cells. Only on surfaces which were coated with a mixture of serum and non-reconstituted collagen, did the majority of the inoculated cells attach singly or as aggregates within 24 h. The attachment of the cells was followed by the outgrowth of cellular processes either from single cells or from aggregates in the same time period. This did not occur on collagen or serum treated or on regular plastic dishes. Under the latter conditions a similar outgrowth was observed only after 3–5 days.     

A simple one-step procedure for staining the nucleolus organizer regions.

A simple silver staining technique for routine use is described by which the nucleolus organizer regions of mammalian chromosomes, including those of mouse chromosomes, are stained selectively.     

A study of irrigation fluids for neurosurgery on brain primary cell cultures

Summary Primary cell cultures from newborn rat brain hemispheres were exposed to different irrigation fluids used in neurosurgery. The cells died after incubation for 5 min with hydrogen peroxide, and the number of cells was drastically decreased after 10 sec of incubation. They shrank after incubation in Elliott's artificial cerebrospinal fluid for 3 h, but the viability as determined by trypan blue exclusion test was not affected. Physiological sodium chloride, Ringer's solution and the culture medium 199 with Hank's salt had no noticeable effect on the viability or morphology of the cells.Acknowledgments. This study was supported by grants from the Medical Faculty of Göteborg and from Statens Naturvetenskapliga Forskningsråd. We want to thank Dr Åke Sellström and Dr Hans-Arne Hansson for valuable discussions.     

A simple gas liquid chromatography procedure for determination of cannabinoidic acids inCannabis sativa L.

Résumé La chromatographie gazeuse des extraits de la marihuana donne la quantité complète de chaque composant cannabinoïque; tandis que la silylation des extraits précédant la chromatographie gazeuse, fournit des informations indépendentes sur les formes acides et non acides de chaque composant cannabinoïque.

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Department of Pharmacognosy, School of Pharmacy, University of Mississippi, research supported by National Institute of Mental Health, Contract No. HSM-42-70-109.     

A simple technique for obtaining carbon replicas from small organisms

Résumé Exposé d'une méthode permettant de faire des répliques au carbone de petits organismes tel que les aphides. L'utilisation d'un substrat de technovit^® pour fixer les organismes est la partie importante de cette méthode. Le technovit a la propriété de coller la pellicule de carbonne; ainsi lorsque l'on détache celle-ci à l'aide de collodion, on obtient seulement la réplique se trouvant sur l'organisme.     

A simple system for mechanical and electrical recordings from frog nerve-muscle preparation

Summary A device is described which can be used for simultaneous measurement of the muscle action potential and the contraction of the frog gastrocnemius nerve-muscle preparation. The apparatus is characterized by ease of construction, good accuracy and reliability.We thank Ms.C. Friedemann for preparation of the drawings; Ms.A. Middelmann for technical assistance.     

A simple method for the collection of leucocytes from rat blood

Zusammenfassung Blutleukozyten von Ratten wurden mit menschlichem (normalem) Serum behandelt. Die Viabilität dieser Präparationen konnte dadurch demonstriert werden, dass die Zellen durch Phytohemagglutinin in «blast» Formen umgewandelt wurden.     

A simple procedure for the photometric evaluation of incidental findings on the recording strips of the Burkard pollen-and-spore trap

Summary Reference is made to a procedure for evaluating certain incidental findings presented by particles of soot or dust on the adhesive strips of the Burkard pollen-and-spore trap or the slides of the similar Hirst apparatus. For this an evaluating device is recommended that is generally used for pherograms in large hospitals today. The often very noticeable streaks of soot or dust particles on the adhesive layer can be assessed with this method. Furthermore, it is possible to determine the time of the occurrence of the particles and possibly to relate them to the velocity and direction of the wind, and also eventually to detect the source of the polluting material.Acknowledgments. We would like to thank Prof. R. Schuppli, director of the Dermatological Department of the Basel Cantonal Hospital, for making it possible to carry out extended monitoring of airborne particles. Our special thanks go to Dr H.P. Rieder, head of the protein-testing laboratory of the Basel Cantonal Hospital, for enabling the examinations with the pherogram evaluator to be made. Finally, we wish to thank the Swiss National Foundation for the Advancement of Scientific Research who has made a grant-in-aid available to Dr R.M. Leuschner for monitoring airborne particles.     

An improved technique of preparing primary cultures of isolated cells from adult frog kidney

Zusammenfassung Eine verbesserte Technik zur Gewinnung der ersten Einzelschichtbildungen von Froschnierenzellen wurde entwickelt. Die Zellen werden in neuem auflösendem Nährboden isoliert und wachsen auf modifiziertem Eagle-Nährboden mit 13% Kalbsserum. Nach 10 Tagen zeigt sich stark aktives mitotisches Zellwachstum in der Kultur.