Hydroxocobalamin. II. Absorption from the Site of Injection and Uptake by the Liver and Calf Muscle in Man

Labeled hydroxocobalamin, administered intramuscularly in man, is absorbed more slowly from the site of injection and deposited in the liver andcalf muscle to a degree equal to or higher than that of cyanocobalamin at anequivalent dose. These findings, together with those reported in Part I ofthis paper, suggest the applicability of hydroxocobalamin as a long-actingvitamin B₁₂ in man. These conclusions, however, require the support to be obtained from long-range observations on patients with vitamin B₁₂ depletion.

Submitted on June 6, 1961 Accepted on August 1, 1961     

Solubility in amide-water cosolvent systems: a thermodynamic view

The solubility of methyl p-hydroxybenzoate was determined in a series of amide-water cosolvents in the temperature range 25–40 °C. Thermodynamic values for the transfer of the ester between the cosolvent system were calculated using a method which permits a focus on the effects of amide alkylation. The results are interpreted in terms of hydrophobic bonding principles which suggest that the alkyl groups on the amide detract from amide-water interaction and enhance amide-ester interaction.     

PHARMACOKINETICS OF ALCURONIUM IN ELDERLY PATIENTS UNDERGOING TOTAL HIP REPLACEMENT OR AORTIC RECONSTRUCTIVE SURGERY

The pharmacokinetic behaviour of alcuronium was studied in threepatients undergoing resection of an aortic aneurysm, and inanother two patients undergoing total hip replacement (groupI). A control group of five elderly patients undergoing relativelyminor surgery was included (group II). In group I patients,the values of the pharmacokinetic parameters such as plasmaclearance, elimination half-life and the apparent volume ofdistribution of the drug were found to be comparable to thoseobtained in normal young patients in previous studies. The groupII patients, however, were found to have a prolonged eliminationhalf-life as a result of reduced plasma clearance, possiblyan age-related effect. The differences between these two groupsof patients may be explained by the differences in the extentof haemorrhage and fluid replacement or changes in blood circulation,or both. However, alcuronium must still be used cautiously inboth groups of patients, especially in the light of a recentfinding that patients undergoing aortic reconstructive surgeryhave a high frequency of functional renal failure after operation.     

Pigmented carcinoid tumour of the thymus

An asymptomatic thymic tumour, classified as a carcinoid tumour on the basis of its light and electron-microscopic appearances, is described. This tumour was atypical in having foci of melanin pigmentation, the pigment being contained in dendritic melanocytes and melanophages. We suggest that the pigmented cells are not neoplastic and represent latent thymic melanoblasts stimulated in some way by the carcinoid tumour. Alternative explanations are discussed.     

北五味子对犬条件反射的影响

国外文献关于北五味子对条件反射的影响说法不一。本工作就此问题作某些探讨。以拍节音作为条件刺激结合食物强化对犬形成阳性条件反射,而后使其消退,并观察不同剂量的北五味子对消退抑制的影响。实验证明,在条件反射消退初期,对犬使用小剂量(0.03克/公斤)的北五味子能减弱消退抑制;0.05克/公斤时效果不定;0.1—0.2克/公斤时能加强消退抑制.但当消退抑制已巩固形成后,则北五味子不论剂量大小皆不表现任何影响。小剂量北五味子对消退抑制的影响在表现上与咖啡碱相似,但较后者为弱,因为后者当消退抑制巩固形成后仍能使消退抑制减弱。