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991.
Idiopathic retroperitoneal fibrosis. A retrospective analysis of 60 cases   总被引:5,自引:0,他引:5  
Sixty patients with idiopathic retroperitoneal fibrosis presenting between 1965 and 1984 are reviewed. Their mean age at presentation was 56 years and the male:female ratio was 3:1. The commonest presenting symptoms were flank and abdominal pain, weight loss, nausea and polyuria. Physical examination was usually normal, expect for the presence of hypertension. Anaemia and elevation of erythrocyte sedimentation rate were usually present. Proteinuria was found in less than a third of patients at presentation and significant bacteriuria was uncommon. The correct diagnosis was made or suspected in very few patients before referral. The cumulative actuarial survival rate was 86% at 1 year and 78% at 2 years. Seventeen patients died; they were significantly older and more uraemic at the time of referral than those who survived. A few patients did well with either corticosteroid therapy or ureterolysis alone. In the majority, both operation and steroid treatment were necessary. In bilateral obstruction with residual function in both kidneys, bilateral ureterolysis proved superior to unilateral operation (each followed by steroid therapy) in conserving renal function. Operation alone or steroid therapy alone should be considered in cases where steroids or surgery respectively present particular hazards. The less traumatic unilateral operation should be considered in poor risk patients and in those whose renal function is absent on one side. In many survivors, disease activity has persisted for many years. Life-long follow-up is recommended.  相似文献   
992.
993.
[3H]Flunitrazepam (FNZ) binding sites were characterized in homogenates of cat visual cortex during normal postnatal development and following dark rearing from birth. In parallel experiments, the distribution and density of [3H]FNZ binding sites were examined by in vitro autoradiographic or 'scrape' methods. In homogenates, Bmax measurements showed low early values, rising to a peak in receptor density at about 60 days postnatal, followed by a decline in adulthood. At all ages, gamma-aminobutyric acid (GABA) altered the Kd, but not the Bmax of [3H]FNZ binding sites. Kd values showed a general increase with age, parallelled by an increased sensitivity to GABA. Receptor autoradiography revealed that the highest density of [3H]FNZ binding sites was in layer IV of cats of all ages. Deafferentation of extrinsic inputs to the visual cortex by surgical undercutting did not alter this pattern of laminar distribution, indicating that the receptors were associated with intrinsic cortical elements rather than subcortical inputs. Dark rearing had no effect on [3H]FNZ laminar distribution in the visual cortex. The Bmax was higher at 30 days postnatal, but did not differ significantly thereafter. Modulation by GABA was concomitantly higher at 30 days, but lower than normal in dark-reared animals at ages greater than 30 days postnatal. The results are discussed in relation to the normal and abnormal development of GABA receptors in the cat visual cortex.  相似文献   
994.
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   
995.
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   
996.
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   
997.
998.
Humoral control of water and electrolyte excretion during water restriction   总被引:1,自引:0,他引:1  
The goals of the present study were twofold: first, to assess the renal excretory and hormonal responses to chronic water restriction in dogs whose sodium retaining mechanisms had been stimulated through dietary sodium (Na+) deprivation; second, to determine the mediator(s) of the natriuresis which was observed with water restriction in these sodium deprived dogs. Three groups of dogs maintained on a low Na+ diet (5 mEq/day) for two weeks underwent a three day period of water restriction. In normal, intact dogs Group 1 (N = 5), water restriction resulted in a significant increase in Na+ excretion with a net cumulative loss of 26.3 +/- 2.6 mEq over three days. The natriuresis was associated with a significant increase in plasma vasopressin (PAVP) (1.7 to 10.2 pg/mliter) and a significant fall in plasma aldosterone (PALDO) from the levels observed with Na+ restriction alone (24.9 to 12.4 ng/dliter). The natriuresis could not be explained by decreases in food intake as determined by control studies in four dogs. Group 2 (N = 6) dogs had a decrease in PALDO with water restriction that was prevented by means of continuous i.v. aldosterone infusion (6.0 micrograms/kg/day). Dogs in this group failed to demonstrate a natriuresis during three days of water restriction, despite the fact that PAVP rose from 3.3 +/- 0.8 to a peak level of 14.95 +/- 1.9 pg/mliter. Group 3 (N = 6) dogs underwent selective neurohypophysectomy, thus preventing the rise in PAVP during three days of water restriction. In this group, PALDO also remained unchanged from the Na+ deprived level during water restriction, and no natriuresis was observed. We conclude: 1) that the natriuresis which occurs with water restriction is a potent physiological response that occurs even in the Na+ restricted state; and 2) this natriuresis can be explained by a fall in PALDO and not the rise in PAVP.  相似文献   
999.
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   
1000.
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   
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