The electron microscopy of chemosensory hairs

Zusammenfassung Die chemorezeptorischen Haare am Labellum vonPhormia regina wurden im Totalpräparat mit dem Elektronenmikroskop untersucht. Die Anzahl der Moleküle, die an der schwellenwertigen Stimulationsreaktion teilnehmen, wurde abgeschätzt. Es zeigte sich, dass die Empfindlichkeit des olfaktorischen Rezeptors bei weitem die Grössenordnung des Zuckerrezeptors übertrifft.     

Experimental investigations on the influence of X-rays on glycogen content in surviving leucocytes

Riassunto Sono stati irradiati direttamentein vitro leucociti sopravviventi ed è stato studiato il loro contenuto in glicogeno durante la sopravvivenza.I risultati dimostrano un aumento significativo della glicogenolisi nei leucociti irradiati rispetto ai controlli. Riguardo alla perdita del loro contenuto in glicogeno, i linfociti risultano più sensibili dei neutrofili alla irradiazione Roentgen.

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These researches have been performed with the help of the «Lega italiana per la lotta contro i Tumori».     

On maximal oxygen consumption in hypoxic humans

The present paper discusses the factors affecting maximal O2 consumption (VO2max) in hypoxia (4300 m above sea level) along the following lines: 1) In acute hypoxia, the fractional limitation to VO2max imposed by circulatory O2 transport (FQ') is 50%, instead of 70% as in normoxia. This is due to the increase in the blood O2 transport coefficient (beta b) as PO2 decreases, as a consequence of the sigmoidal shape of the O2 dissociation curve of hemoglobin. The remaining 50% is assumed to be equally partitioned between tissue O2 transfer (Ft') and mitochondria O2 utilization (Fm'). 2) In chronic hypoxia, FQ' = 0.45, Ft' = 0.20 and Fm' = 0.35, as a consequence of reduced muscle fiber size and muscle mitochondrial density following acclimatization. 3) The relationship between VO2max and PIO2 in both acute and chronic hypoxia reflects the O2 dissociation curve. 4) Acclimatization to chronic hypoxia does not have the function of preserving VO2max.     

Responses of single neurons in the olfactory bulbs of rabbits,dogs, and cats to X-rays

Zusammenfassung Die durch Röntgenstrahlen (1 R/sec) erzeugten elektrischen Impulse einzelner Nervenzellen der Geruchszwiebel wurden in narkotisierten Katzen, Kaninchen und Hunden gemessen. Als typische Reaktion wurde eine kurzfristige Erhöhung der elektrischen Impulse gefunden. Somit sind die von Röntgenstrahlen ausgelösten elektrischen Impulse des Geruchsystems kein artspezifisches, sondern vielmehr ein allgemeines Phänomen.

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This study was supported through funds provided by the Bureau of Medicine and Surgery, U.S. Navy, and the Defense Atomic Support Agency. The opinions and assertions contained herein are those of the authors and are not to be construed as the official views of the Navy Department.     

Lead distribution in the nervous system of 8-month-old rats intoxicated since birth by lead

Lead levels in the nervous system of rats intoxicated for 8 months by lead acetate (0.2% in drinking water) varied according to the region: the lowest levels were observed in sciatic nerve and the highest in hippocampus and cerebral neocortex, while intermediate levels were observed in pons medulla, cerebellum, midbrain, hypothalamus and striatum.     

Virus-like particles in acute lymphoblastic leukemia

Zusammenfassung In Knochenmark-Monocyten eines fünfjährigen Mädchens konnten im Cytoplasma Einschlüsse beobachtet werden, die mit gewundenen Membranen und virusähnlichen Partikeln fegüllt waren.