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51.
Claus Jacob Alexander Y. Safronov Sonia Wilson H.Allen O. Hill Tim F. Booth 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》1997,431(1):7-10
A novel chiral redox-active ferrocene compound (FcVI) with amphiphilic properties has been synthesized. Cryogenic Transmission Electron Microscopy (cryo-TEM) has been used to estimate the shape and size of the FcVI aggregates in solution. Uni- and multi-lamellar vesicles (between 40 and 300 nm in diameter) were observed in water. Large particles (of more than 1 μm in diameter) with a hexagonal fine structure were found in 50 mM aqueous Na2SO4 solution. Sonication transformed the latter into ‘rosette’-like structures. Cyclic voltammetry has been employed to investigate the electrochemical properties of FcVI. The amphiphile adsorbed on graphite electrodes and a reversible electrochemical behaviour, characteristic of ferrocene, was observed with redox potentials between 330 and 350 mV. 相似文献
52.
A. Robert Spitzer Shalom Stahl David Yarnitsky Ernest W. Johnson John R. Wilson R. A. C. Hughes Stefania Morino Giovanni Antonini Kiyotoshi Kaneko Yoji Ohnishi Tetsushi Atsumi Isao Hozumi Tadashi Miyatake Tetsuo Furukawa James P. Knochel Ikuo Mineo Seiichiro Tarui Francis O. Walker Andrew J. Gitter Walter C. Stolov Nicholas J. Capozzoli 《Muscle & nerve》1996,19(4):531-538
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Cerebrospinal fluid rhinorrhea in patients with untreated pituitary adenoma: report of two cases 总被引:3,自引:0,他引:3
We report the cases of two patients with untreated pituitary adenoma who presented with cerebrospinal fluid rhinorrhea. The surgical treatment and mechanisms involved in this rare condition are discussed. 相似文献
56.
Studies of the rate of clearance of a gellan gum formulation (Gelrite) radiolabelled by the inclusion of technetium-99m labelled diethylenetriaminepentaacetic acid were carried out in volunteer subjects and in rabbits. Disposition was followed by gamma scintigraphy and compared with 0.5% w/v hydroxyethylcellulose (HEC) solution and isotonic saline administered to the same subjects. Clearance of all solutions was found to follow bi-exponential kinetics with differences in clearance rates between the two species studied. A significant retention of the gellan gum formulation compared to HEC (p = 0.006) or saline (p = 0.009) was noted in man, but not in the rabbit. In this latter species the HEC showed greater retention compared to Gelrite. The species-specific differences in the precorneal residence of the formulations are attributed to the different physiological responses following instillation of solutions into the eye. 相似文献
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59.
C M Wilson R J Merritt D W Thomas 《JPEN. Journal of parenteral and enteral nutrition》1988,12(1):81-83
An 11-month-old infant with a central venous catheter for total parenteral nutrition for short gut syndrome developed head and neck swelling. A thrombus at the catheter tip occluding the superior vena cava was demonstrated roentgenographically. A 48-hr infusion of urokinase (4400 units/kg/hr) was administered for thrombolysis. The thrombus cleared clinically and roentgenographically without adverse effects. There has been no recurrence of the superior vena cava syndrome. Urokinase infusion is an alternative to immediate catheter removal in selected patients. 相似文献
60.
G. Singh J. F. Hussain A. MacKinnon C. M. Brown D. A. Kendall V. G. Wilson 《Naunyn-Schmiedeberg's archives of pharmacology》1994,351(1):17-26
In the present study we have prepared crude, methanolic extracts of bovine lung and bovine brain and, using radioligand binding assays in conjunction with a number of simple chromatographic techniques, provided evidence for the presence of a non-catecholamine ’clonidine-displacing substance‘ (CDS). The level of CDS in lung extracts (9?units/g wet weight n=11) is approximately 3 times that in the brain extracts. Furthermore, the effect of the crude, methanolic extracts are selective for non-adrenoceptor, imidazoline (labelled by [ 3H]-idazoxan) and a 2-adrenoceptor binding sites (labelled by [ 3H]-clonidine); both extracts are 5–10-fold more potent displacers of ligand binding to a 2-adrenoceptors compared with binding to opiate receptors (labelled by [ 3H]-etorphine) and practically inactive against a 1-adrenoceptor and muscarinic binding sites (labelled by [ 3H]- prazosin and [ 3H]-quinuclidinyl benzilate, respectively). With the exception of the non-adrenoceptor, imidazoline binding assay, which used rat kidney membranes labelled by [ 3H]-idazoxan in the presence of the a 2-adrenoceptor antagonist RS-15385-197, all radioreceptor assays involved bovine cerebral cortex membranes. Although the extracts contain catecholamines (brain only), histamine (lung only) and monovalent cations (both), which have the potential to interfere with the radioligand binding assays, their concentrations were too low to account for the effects observed. Preliminary attempts at purification of the extracts revealed that CDS activities from the two tissues are similar, i.e., practically insoluble in organic solvents at room temperature, not affected by either Sep-Pak C 18 column or anion exchange resins but retained (along with the monovalent cations) by cation exchange resin. However, following chromatographic separation on a Biogel P2 column, the CDS-containing eluates are cation-free and exhibit qualitatively similar elution profiles. Future experiments will involve further purification of ’clonidine-displacing substance‘ to characterize its interaction with a 2-adrenoceptor binding sites in greater detail and establish whether it has biological activity consistent with the properties implied by its effects in radioligand binding assays. 相似文献