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991.
992.
Mineral trioxide aggregate (MTA) is being advocated for vital pulp therapy. In the case of direct pulp capping, hemorrhage control is an important step on success, but little is known about the effect of MTA on pulpal bleeding. In addition, there has been a lack of information on the effect of MTA on smooth muscle contraction, such as can occur in the blood vessels of dental pulp. The present study assessed the vascular effects of MTA, using the rat aortic ring preparations as a tissue model. MTA (100-500 mg) induced dose-dependent contraction in rat thoracic aorta. The contractile effect of MTA was blocked by calcium channel blocker nifedipine (1 muM). These data suggest that the vasoconstrictor property of MTA is related to calcium influx and it may allow proper control of hemorrhage which is critical for the success of any pulp-capping treatment.  相似文献   
993.
994.
Neuroleptic malignant syndrome (NMS) is the rarest and most serious of the neuroleptic-induced movement disorders. We describe a case of neuroleptic malignant syndrome (NMS) associated with the use of ziprasidone. Although conventional neuroleptics are more frequently associated with NMS, atypical antipsychotic drugs like ziprasidone may also be a cause. The patient is a 24-year-old male with a history of schizophrenia who developed signs and symptoms of NMS after 2 days of treatment with an 80-mg/day dose of orally administrated ziprasidone. This case is the earliest (second day of treatment) NMS due to ziprasidone reported in the literature.  相似文献   
995.
Five-day-old Wistar albino rats were injected with kainic acid (KA) or saline i.p. to investigate time-dependent alterations in morphology and number of basic fibroblast growth factor (bFGF) immunoreactive (-ir) astrocytes and neurons in hippocampus at 15, 30, and 90 days after the injections. Sections were stained with cresyl violet for morphological evaluation and bFGF immunohistochemistry was used for quantitative evaluation of bFGF-ir cell density. Fifteen days after KA injection, there was gliosis but no neuronal loss although disorganization in CA1, CA3, CA4 pyramidal layers and neuronal loss were evident 30 and 90 days after the injection. KA injected rats demonstrated significantly increased number of bFGF-ir astrocytes throughout the hippocampus and pyramidal neurons in CA2 after 15 days and decreased number of bFGF-ir cells after 30 and 90 days. The decrease in the number of bFGF-ir astroglia and neurons in long term after KA injection may indicate a decrease in the production of bFGF and/or number of bFGF-ir cells suggesting that protective effects of bFGF may be altered during epileptogenesis in hippocampus.  相似文献   
996.
OBJECTIVE: In this study, we aimed to examine time-dependent morphologic changes and quantitative alterations in the density of basic fibroblast growth factor (bFGF)-immunoreactive (ir) astrocytes and CA2 pyramidal neurons in dorsal hippocampus of rats after status epilepticus (SE) induced by kainic acid (KA) injection. METHODS: Wistar albino rats were injected with saline or KA i.p. to investigate time-dependent alterations in morphology and the number of bFGF-ir astrocytes and neurons in the dorsal hippocampus 15, 30 and 90 days after KA injection. RESULTS: Fifteen days after KA injection, gliosis was present throughout the hippocampus and neuronal loss was evident in CA1 and CA3 regions, which was more severe after 30 and 90 days. KA-injected rats demonstrated significantly increased number of both bFGF-ir astrocytes throughout the hippocampus and pyramidal neurons in CA2 after 15 days and decreased number after 30 and 90 days. CONCLUSION: The decrease in the number of bFGF-ir astroglia and neurons in long term after KA injection may indicate a decrease in the production of bFGF and/or number of bFGF-ir cells, suggesting that protective effects of bFGF might be altered during epileptogenesis in the hippocampus.  相似文献   
997.
998.
Objective  We aimed to describe the epidemiologic, clinical, laboratory features, neuroimaging, treatment, and outcome of children with acute disseminated encephalomyelitis in a cohort study. Methods  In this study, twelve children who were diagnosed as acute disseminated encephalomyelitis were reviewed retrospectively. All of the cases were reevaluated with systemic and neurological examinations, serologic tests, cerebrospinal fluid investigations, magnetic resonance imaging. Result  Their age ranged between 2.5 and 16 years. Five of the cases had initial infections. Patients presented most often with motor deficits (75%), secondly with loss of conscious (33%), and seizures (33%). Spinal fluid abnormalities occurred in 41.6%. Cranial, and spinal magnetic resonance imaging (MRI) revealed hyperintense signal changes mainly in basal ganglia and thalamus (58%), cortical and subcortical areas (33) in T2 weighted images. Myelitis was determined in two cases. Six patients were treated with steroid, and 3 were treated with intravenous immunoglobulin. Ten patients recovered completely. We observed relapse in one case and recurrence in two cases. These cases responded well to high dose intravenous prednisolone followed by oral prednisolone for 6 months. Conclusion  Outlook recovery is generally good in acute disseminated encephalomyelitis. Recurrence and neurological deficits are rarely seen. Early treatment of prednisolone is one of the most important factors to determine the prognosis in this disease.  相似文献   
999.
Inflammatory mediators play a major role in the pathogenesis of respiratory syncytial virus (RSV) infection. The objective of this study was to evaluate the effect of i.v. dexamethasone on cytokine concentrations in tracheal aspirates (TA) of children with severe RSV disease and to correlate them with disease severity. Twenty-five cytokines were measured in TA obtained from children <2 yr old intubated for severe RSV disease, and enrolled in a double-blind study of i.v. dexamethasone (0.5 mg/kg; n = 22) vs. placebo (n = 19). Cytokine concentrations, measured at baseline and days 1 and 5 post-randomization using a multiplex assay, were compared within both treatment groups and correlated with: (i) tracheal white blood cell counts, (ii) tracheal RSV loads by culture and (iii) parameters of disease severity, including number of days of requirement for mechanical ventilation, intensive care unit (ICU), and hospitalization. At baseline interleukin (IL)-13 and IL-15 concentrations were significantly higher in the dexamethasone treatment group. On day 1 post-treatment, only MCP-1, eotaxin and IL-6 concentrations were significantly different but higher in the placebo group. On day 5: IL-13, IL-7, IL-8 and MIP-1α concentrations were higher in dexamethasone-treated patients. In both groups MIP-1β inversely correlated with the days of ventilator support; MIP-1α, MIP-1β and eotaxin inversely correlated with ICU days; and IL-6 inversely correlated with hospitalization regardless of the treatment assigned. Systemic administration of dexamethasone did not have a consistent effect on TA concentrations of pro-inflammatory cytokines. This may help explain, at least in part, the lack of clinical benefit of steroid treatment in children with severe RSV bronchiolitis.  相似文献   
1000.
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