Resumen por el autor, David M. Siperstein. Universidad de Minnesota.Los efectos de la inanici6n aguda y crbnica sobre el desarrollo y la estructura del testiculo de la rata albina.El desarrollo postnatal normal del testiculo ha sido estudiado por el autor en una serie de ratas albinas. Estos testiculos fueron comparados con 10s de ratas sometidas a una alimentacibn deficiente durante varios periodos. IJnas c u h t a s ratas fueron alimentadas con una dieta abundante despuks de una inanicibn prolongada. Los resultados mlis iinportantes de estos estudios son 10s sigdentes: 1. En ratas de dos dias el testiculo aumenta en peso a pesar de haber sometido a1 animal a1 hambre durante 48 a 50 horas, per0 las mitosis disminuyen en ndmero y el proceso normal de la diferenciaci6n histolbgica cesa. 2. Durante el periodo de nutrici6n deficiente durante tiempo variable en ratas de tree semanas, la mitosis contin6a en las cklulas de 10s tubos seminiferos, pero el proceso de la espermatoghesis cesa en el estado de espermatocito primario. Los espermatocitos degeneran y son reabsorbidos. Las espermatogonias y c6lulas de Sertoli solamente presentan cambios degenerativos en 10s casos de inanicibn extrema. 3. La inanicibn aguda en las ratas adultas con pdrdida del 30 a 47 por ciento del peso total produce cambios degenerativos en unos cuhntos tdbulos esparcidos irregularmente. Todos 10s demhs tGbulos presentan una estructura normal en apariencia. 4. La mitosis es muy persistente en el epitelio seminifero y tiene lugar a6n en aquellos ttibulos en 10s cuales casi todas las c6lulas aparecen m8s o menos degeneradas. 5 . La alimentacibn abundante despubs de una inanicibn prolongada (comenzada a las tres semanas de edad y extendida sobre 12 a 20 semanas) da como resultado la vuelta rApida a la estructura histolbgica normal. 6. Durante el periodo regenerativo el autor ha comprobado la existencia de una hipertrofia definida del tejido intersticial e hiperplasia de las c6lulas interst iciales.
Blood transfusion in infants and children is a recognized therapeutic procedure. In the past, the site of transfusion has been limited to the superior longitudinal sinus in the region of the anterior fontanel, or to the direct exposure of some vein, preferably in the elbow.The anterior fontanel route, popularized by Helmholz1 in 1915, affords an excellent method in infants in whom this structure is accessible. This approach, however, has its limitations. Fischer,2 Lowenburg,3 Unger,4 and others, have pointed out the dangers inherent in puncturing the superior longitudinal sinus.
These results are based on a study of over 100 rabbits. Freshly citrated blood was injected iminediately into the peritoneal cavity of normal and anemic rabbits. In several instances, citrated pigeon's cells were introduced into the abdominal cavity of rabbits. A11 the animals were subjected to careful blood studies. They were killed and autopsied at the end of each series of experiments.We think that freshly citrated blood injected into the peritoneal cavity of rabbits is absorbed, because:1. Autopsies at various intervals following the operation show that the quantity present in the abdominal cavity rapidly decreases in amount, and that absorption of comparatively large amounts of blood (one-fifth of the total blood volume) is complete in 3-4 hours.2. Estimations of blood values show definite increase from the time the blood is transfused until the animal is killed.We think that erythrocytes enter the blood without undergoing any morphological changes, because :1. Smears, taken at the autopsy, of the fluid in the abdominal cavity show no change in the size, shape or structure of the corpuscles and no evidence of hemolysis.2. Our experiments show a rise in hemog1o.bin and cellular elements following transfusions in normal and anemic animals which cannot be accounted for by a mere concentration of the blood.3. Nucleated corpuscles of pigeons when injected intraperitoneally into rabbits can be recovered from the general circulation in 15 minutes.We submit the following additional evidence that the erythrocytes function, because :
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