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991.
It has been reported previously that neurons in the dorsal lateral geniculate nucleus (LGN) of cats with neonatal damage to visual cortex (KVC cats) have receptive fields that are abnormally large and that the receptive fields of these neurons sometimes do not appear to conform to the normal retinotopic order in the LGN. A primary aim of this study was to determine if these physiological abnormalities are related to inappropriate patterns of retinogeniculate connections. We therefore have analyzed the terminal arbors of retinogeniculate axons in adult cats that had received a lesion of visual cortex (areas 17, 18, and 19) on the day of birth. Single retinogeniculate axons were characterized physiologically and injected intracellularly with horseradish peroxidase. Consistent with earlier reports that neonatal removal of visual cortex results in a retrograde loss of retinal X-cells, all of the retinogeniculate axons that we recorded were from Y-cells. While the visual responses of these Y-cell axons were normal, the morphology of their terminal arbors in the LGN was abnormal. Retinal Y-cell axons in KVC cats have terminal fields in the A laminae of the LGN that are as large or larger than those of normal Y-cells. However, since the LGN in KVC cats is severely degenerated, single Y-cell arbors occupy a proportional volume of the LGN that is 12 times greater than normal. Thus an early lesion of visual cortex produces a severe mismatch between retinogeniculate axon arbor size and target size. Also, despite the normal size of retinogeniculate axon arbors in KVC cats, the number and density of terminal boutons are greatly decreased. Thus our morphological results suggest that the unusually large receptive fields of LGN cells in KVC cats and the relative lack of retinotopic precision in the LGN are due, at least in part, to anomalies in the relative size and distribution of retinogeniculate axon arbors that develop after neonatal removal of visual cortex. 相似文献
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A method is described for the simultaneous assay of non-conjugated androstenedione, dehydroepiandrosterone, testosterone, cortisol, aldosterone and 18-hydroxycorticosterone in urine. The method involves solid-phase extraction, automatic high performance liquid chromatography and subsequent radioimmunological quantitation of the individual steroids. Excretion rates of these urinary free steroids were determined in normal males and females. There were no significant sex differences in excretion rates, although both urinary free testosterone and dehydroepiandrosterone were distinctly lower in females than in males. Representative measurements of the excretion rates of patients with Cushing's disease, Addison's disease, ectopic corticotropin syndrome and hirsutism were made. The present method has been shown to be well suited for routine purposes. Its final diagnostic significance for monitoring alterations in glucocorticoid, mineralocorticoid and androgenic activity of the adrenal cortex has yet to be explored. 相似文献
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997.
The technique of selective renal occlusion phlebography using Swan-Ganz or Dotter-Lucas balloon catheters is described. The
Swan-Ganz catheter is introduced into the femoral vein with the aid of a Cordis introducer system. The Dotter-Lucas balloon
catheter is inserted via the same route using a combination of either a Desilets-Hoffman or Edslab introducer, along with
a Gebauer introducer. Occlusion of the renal vein is achieved by insufflation of the balloon with air or injection of saline
or dilute contrast media into the balloon.
Selectíve renal occlusion phlebography was performed in 116 patients in order to exclude renal vein thrombosis, to delineate
poorly vascularized renal masses, to determine the venous involvement of a renal tumor, and to assess the patency of splenorenal
shunts.
Renal occlusion phlebography optimizes the retrograde opacification of the renal veins. It has value in the delineation of
poorly vascularized renal masses and in the determination of the venous involvement of renal and retroperitoneal tumors, and
it would seem to be the method of choice for demonstrating the patency of surgical splenorenal shunts. Further enhancement
of venous opacification by the combination of temporary arterial vasoconstriction with angiotensin (pharmaco-occlusion phlebography)and
venous balloon occlusion is useful in some cases.
A preliminary report was presented at the Annual Meeting of the American Roentgen Ray Society, Washington, D.C., September
1976 相似文献
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Karl-Artur Kovar Ilse Schlecht Renate Weber Adriano Guarnieri Lucilla Varoli 《Archiv der Pharmazie》1985,318(2):149-157
Nitro Products of Antazoline and Bamipine and Their Meisenheimer Compounds with Acetone and Bases Under the conditions of the Vitali-Morin reaction, antazoline and bamipine are nitrated to yield 17 nitro compounds, namely 1a/2b, 1b/2d, 1c, 1d/2e, 1e, 1f, 1g/2g, 2a, 2c, 2f, 2h–2n . Of these 1b/2d, 1c, 1e–1g/2g, 2a, 2c, 2h–2l produce coloured products when treated with bases in acetone. The coloured products 3a/b, 4a/b, 5a/b and 7 are Meisenheimer cyclohexadienate and propenide salts. 相似文献