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941.
R. C. Peatfield 《Acta neurologica Scandinavica》1987,76(5):340-345
Two patients with a chronic non-progressive illness beginning with undue sleepiness and personality change are described. Both have an atypical movement disorder, clearly distinct from Parkinson's disease. Each has an impairment of memory and learning with relative preservation of arithmetical, language and visuospatial tasks, suggesting a subcortical dementia. Both have atrophy of deep structures on their CT scans, and elevated antibodies to one of the Coxsackie viruses. It is suggested that insidious virus encephalitis (perhaps cases that would previously have been described as encephalitis lethargica) still occurs, and is among the causes of subcortical dementia. 相似文献
942.
Aldosterone production by suspensions of adrenal glomerulosa cells obtained from young and old cows was measured. Basal steroidogenesis was lower in cells from old cows, as were the responses to angiotensin II (AII), potassium, ACTH and dibutyryl cyclic AMP. Receptors for AII and aldosterone production from added progesterone were the same in old and young cells. Synthesis of pregnenolone from endogenous precursor, the 'early pathway' of aldosteronogenesis, was lower in old cells than in young. AII-stimulated incorporation of 32P into phosphatidylinositol and the change in 45Ca2+ flux induced by AII were diminished in old cells. Overall protein synthesis, measured by 3H leucine incorporation, was lower in old cells than young, but was not affected by AII in either. Diminished responsiveness of adrenal glomerulosa cells from old animals results from a change in postreceptor events that affect the early pathway of aldosteronogenesis. 相似文献
943.
Cholinoceptor-mediated mechanical and electrical responses of rat oesophageal striated musculature. A comparison of two in vitro methods 总被引:1,自引:0,他引:1
1. Both muscarinic and nicotinic cholinoceptor agonists produce a contractile response of the rat oesophageal tunica muscularis externa (TME) in vitro. 2. The muscarinic receptor-mediated responses were confined to the distal 0.5 cm of the TME, which contains an admixture of smooth muscle. 3. Nicotinic receptor-mediated responses were obtained throughout the length of the TME striated musculature and consisted of a fast and slow component, representing TTX-sensitive contractions, associated with muscle action potentials, and electrically silent contractures, respectively. 4. Contractions were observed only in superfused preparations. 5. Contractures were resistant to changes in extracellular cation concentrations designed to eliminate generation of nerve and muscle action potentials or release of neurotransmitters. 相似文献
944.
945.
Chemically distinct rat olivocochlear neurons. 总被引:6,自引:0,他引:6
We have produced a neurochemical map of the cell bodies of origin of the cochlear efferent terminals in rat by combining glutamic acid decarboxylase (GAD), choline acetyltransferase (ChAT), or calcitonin gene-related peptide (CGRP) immunocytochemistry with retrograde transport of horseradish peroxidase. The locations of cochlear efferent cell bodies are in general agreement with the medial and lateral systems described by White and Warr (J. Comp. Neurol. 219:203-214, 1983) with some minor modifications. The lateral system consists of at least two pools of chemically distinct neurons located within the lateral superior olive (LSO) ipsilateral to the injected cochlea. One pool immunostains with an antibody to GAD while the other immunostains with antibodies to ChAT and to CGRP. The medial efferent system consists of periolivary neurons that are almost exclusively large and ChAT-positive but CGRP-negative. They are located both ipsilateral and contralateral to the cochlea they project to. There are a few GAD-positive small neurons in the medioventral and rostral periolivary regions that project ipsilaterally, but these may prove tobe ectopic neurons. The ipsilateral lateroventral periolivary region (LVPO) contains some efferent neurons, all of which are ChAT-positive but CGRP-negative. Additional cochlear efferent neurons, some of which are ChAT-positive and others GAD-positive, are present within and immediately dorsal to the fiber capsule surrounding the medial limb, and to a lesser extent the lateral limb, of the ipsilateral LSO. Not all GAD-positive or ChAT-positive olivary cells project to the cochlea. We have complemented the results in the brainstem by demonstrating two immunocytochemically distinct populations of efferent terminals in the cochlea simultaneously, one CGRP-positive and the other GAD-positive. Approximately equal numbers of boutons immunoreactive for both markers are present beneath inner hair cells throughout the entire length of the cochlea. Surprisingly high numbers of GAD-positive and CGRP-positive boutons are also present on outer hair cells, with each class having its spatially and morphologically distinct features. The lack of CGRP-positive periolivary cells that are retrogradely labeled by cochlear injections of HRP suggests that the lateral olivocochlear system sends projections to outer hair cells. Our results raise questions about species differences in the organization of targets of the lateral and medial olivocochlear systems. 相似文献
946.
A 59-year-old man developed dystonia and reflex sympathetic dystrophy after receiving high doses of ergotamine for migraine treatment. Ischemia is suggested as the precipitating factor. 相似文献
947.
Three patients with polymyositis refractory to conventional steroid and immunosuppressive treatment, but responsive to cyclosporin A, are described. In a fourth patient cyclosporin A was used as a first line drug in combination with steroids in the treatment of life-threatening dermatomyositis. Cyclosporin A in the management of polymyositis/dermatomyositis requires formal assessment of its costs and benefits compared with conventional treatments. 相似文献
948.
949.
950.
We developed a homogeneous fluoroimmunoassay for detecting amphetamines in urine. Only fluorescence intensity need be measured because the emission of non-protein-bound fluorescein-labeled amphetamine is preferentially quenched by detergent micelles. In a previous reported prototype assay system for measuring gentamicin in serum we used fluorescein and dodecyl sulfate (Anal Chem 1985; 57:1928-30). We have found that favorable hydrophobic and (or) ionic character of the analyte and unfavorable polar and (or) ionic character of the fluor are important determinants of the desired interactions. An anionic detergent and fluorescein, therefore, should be appropriate for apolar of cationic analytes, such as gentamicin and amphetamines. A greater [H+] at the anionic micelle surface is important for quenching emission from the fluor moiety. Millimolar concentrations of dodecyl sulfate rapidly denature immunoglobulin unless hapten is bound with sufficiently high affinity. Affinity was sufficiently high for the antibody used in the prototype gentamicin assay but not for the amphetamine antibody. Thus for the amphetamine assay, we used a non-denaturing detergent, dodecyl(oxyethylene)12 sulfate. The assay requires 30 microL of specimen in 2 mL of total assay volume. Amphetamine(d-,dl-, and meth-), at a concentration of 1 mg per liter of urine, is readily detected. 相似文献