Demonstration of a net movement of water through the lens

Résumé Des cristallins de lapins couvés dans des diméthylsilicones sécrètent un fluide à leur surface antérieure. Ce fluide peut prendre le même aspect et la même réticulation qu'un morceau du tissu de la surface postérieure, si le cristallin est excisé promptement après la mort.

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This work was supported in part by a grant from the Institute of Neurological Diseases and Blindness N.I.H., No. NBO1979. The technical assistance ofR. Lukanen and CarolynMcDonald with picture taking and lens preparation respectively is gratefully acknowledged. The author gives a special thanks to Prof.J. E. Harris for helpful discussions and encouragement wihch led to this work.     

Amplification of immunoglobulin lambda constant genes in populations of wild mice

The lambda immunoglobulin light chain (Ig lambda) locus of BALB/c inbred mice consists of two variable region gene segments (V lambda)1-3, and four constant region gene segments (C lambda)1,2,4,5. Each C lambda gene segment is associated with a unique joining segment (J lambda)2,4-7, and they are organized in two paired units, J3C3-J1C1 and J2C2-J4C4 (refs 4, 8). Using cDNA probes specific for C lambda 1 and C lambda 2 (ref. 9) we have analysed the genomic organization of the C lambda gene segments in wild-derived and inbred strains of mice. Although Southern blots of the genomic DNA of inbred mice show a constant pattern of hybridization, wild-derived mice show a high degree of variation in the number, size and intensity of hybridizing fragments. We have now found that, per haploid genome, mice of a Mus musculus musculus stock isolated from Sladeckovce, Czechoslovakia (CzII) have at least 12 C lambda segments, and mice of a Mus musculus domesticus stock 'Centreville Lights' from Centreville, Maryland (CL) have at least 8 C lambda segments. There appears to have been relatively recent amplifications of the C lambda gene segments in wild mice.     

Effect of acetylsalicylic acid on iron absorption in the rat

Summary The in vivo administration of⁵⁹Fe to the rat accompanied by acetylsalicylic acid (ASA) enhanced significantly counts in blood, spleen, liver and femur without affecting those of the intestine. The results suggest that ASA augments iron absorption either via an inhibitory action on the synthesis of prostaglandins or by a purely chemical mechanism.This work was supported by Grant No. 6638 from CONICET (Argentina).The technical assistance of Mrs María E. Castro and Mrs Patricia Dubra is gratefully acknowledged.     

Development of oxidative metabolism in the non-innervated optic lobe of the chick.

Early removal of the optic cup of the chick embryo prevents innervation of the contralateral optic lobe. This reduces the rate of development od citrate synthetase. The posthatch increase of the level of this enzyme related to oxidative metabolism is not impaired by denervation of the chick optic lobe.     

Effect of chemical sympathectomy,adrenalectomy and adrenergicα- andβ-blocking agents on the development of hyperglycemia induced by streptozotocin in the rat

Summary The sympathetic nervous system in the rat does not play any significant role in the streptozotocin-induced and tolbutamipe-induced hypoglycemia.