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81.
Acquired pendular nystagmus: its characteristics, localising value and pathophysiology 总被引:5,自引:4,他引:1 下载免费PDF全文
Investigations were made of 16 patients with acquired pendular nystagmus and a further 32 cases reported in the literature were reviewed. Amongst our own patients two thirds had multiple sclerosis, almost one third a cerebrovascular accident or angioma and two had optic atrophy with squint. The nystagmus took forms which could be monocular or binocular, conjugate or disconjugate and could involve movements about single or multiple axes. Spectral analysis was used to characterise the amplitude and frequency of the movements and to estimate the degree of relationship (coherence) between movements of the two eyes or between movements of one eye about several axes. The oscillations ranged in frequency from 2·5 Hz to 6 Hz, with typical amplitudes between 3° and 5°. In a given patient all oscillations, regardless of plane, were highly synchronised. Somatic tremors of the upper limb, face and palate associated with the nystagmus were often at similar frequencies to the eye movement. The other ocular signs common to all our patients were the presence of squint with failure of convergence. Most patients also had skew deviation or internuclear ophthalmoplegia or both. The major oculomotor systems, that is, saccades, pursuit, optokinetic and vestibulo-ocular reflexes could be intact. It is inferred that the mechanism responsible for the pendular nystagmus lies at a level which is close to the oculomotor nuclei so that it can have monocular effects but is not part of the primary motor pathways. It is possible that this mechanism normally subserves maintenance of conjugate movement and posture of the eyes. The periodicity of the nystagmus is likely to arise from instability in a certain type(s) of neurone, for the associated somatic tremors have similar characteristics and yet involve very different neuronal muscular circuitry. Prognosis for cessation of the nystagmus is poor. In five patients with multiple sclerosis it was suppressed by intravenous hyoscine with, however, unacceptable subsequent side effects. 相似文献
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Localisation of NMU1R and NMU2R in human and rat central nervous system and effects of neuromedin-U following central administration in rats 总被引:4,自引:0,他引:4
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Shen V Li X Murdock M Resnansky L McCluskey ER Semba CP;COOL Investigators 《Journal of pediatric hematology/oncology》2003,25(1):38-45
PURPOSE: To evaluate the safety and efficacy of alteplase for restoring function to occluded central venous catheters in a pediatric population. PATIENTS AND METHODS: A phase III, open-label, single-arm, multicenter trial was performed in 995 adult and pediatric patients with dysfunctional nondialysis catheters and ports. This report is a subset analysis of subjects between 2 and 18 years of age (N = 122) who were enrolled in the study. Alteplase (2 mg/2 mL) was instilled into the dysfunctional catheter lumen and assessed at 30 and 120 minutes. Subjects weighing > or =30 kg received 2 mL of alteplase; subjects <30 kg received 110% of the internal lumen volume (not exceeding 2 mL). Alteplase dosing was repeated once after 120 minutes if the catheter remained dysfunctional. The primary safety endpoint was the rate of intracranial hemorrhage (ICH) within 5 days of treatment. RESULTS: The overall efficacy following up to two instilled doses of alteplase was 87%. In 70 patients (57%), restoration of catheter flow occurred by 30 minutes following a single dose of alteplase. Restoration of function was related to the duration of occlusion (P = 0.04). For catheters with occlusions of 0, 1 to 14, and >14 days duration, the efficacy was 91%, 78%, and 60%, respectively. Success was independent of the patient's age, sex, body weight, CVC type, or catheter age. There were no cases of death, ICH, major bleeding episodes, or embolic events attributable to treatment. CONCLUSIONS: An alteplase regimen of up to two 2-mg doses is safe and effective for restoration of function to occluded central venous catheters in a pediatric population. 相似文献
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Neurokinin 1 receptor and relative abundance of the short and long isoforms in the human brain 总被引:7,自引:0,他引:7
Caberlotto L Hurd YL Murdock P Wahlin JP Melotto S Corsi M Carletti R 《The European journal of neuroscience》2003,17(9):1736-1746
Substance P exerts its various biochemical effects mainly via interactions through neurokinin-1 receptors (NK1). Recently, the NK1 receptor has attracted considerable interest for its possible role in a variety of psychiatric disorders including depression and anxiety. However, little is known regarding the anatomical distribution of NK1 in the human central nervous system (CNS). Riboprobe in situ hybridization, quantitative PCR and in vitro autoradiography were performed. Highest NK1 mRNA levels were localized in the locus coeruleus and ventral striatum, while moderate hybridization signals were observed in the cerebral cortex (most abundant in the visual cortex), hippocampus and different amygdaloid nuclei. Very low levels of the NK1 mRNA were detected in the cerebellum and thalamus. In view of the existence of a long and short isoform of the NK1 receptor, it was of interest to assess whether there was a differential distribution of the two splice variants in the human CNS and peripheral tissues. A quantitative TaqMan PCR analysis showed that the long NK1 isoform was the most prevalent throughout the human brain, while in peripheral tissues the truncated form was the most represented. 3H-Substance P autoradiography revealed a good correlation between receptor binding sites and NK1 mRNA expression throughout the brain, with the highest levels of binding in the locus coeruleus. These results provide the anatomical evidence that the NK1 receptors have a strong association with neuronal systems relevant to mood regulation and stress in the human brain, but do not suggest a region-specific role of the two isoforms in the CNS. 相似文献
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The orbital apex, formed by the superior orbital fissure and optic canal, is the cross-road between the orbit and the intracranial structures. Pathological processes may extend intracranially via the superior orbital fissure and vice versa. In addition to intrinsic soft tissue lesions, various pathological processes may involve the surrounding osseous anatomy. Malignant lesions arising from adjacent structures or from haematogeneous metastasis may also infiltrate this region. 相似文献
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