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91.
Complications of epidural anesthesia: MR appearance of abnormalities   总被引:5,自引:0,他引:5  
  相似文献   
92.
Methylenedioxymethamphetamine (MDMA) is a phenylethylamine with novel mood-altering properties in humans. MDMA shares the dopamine-releasing properties of amphetamine but has been found to be a more potent releaser of serotonin (5-HT). The present study undertook to determine the relative roles of dopamine and 5-HT release in MDMA-induced locomotor hyperactivity. S-(+)MDMA produced dose-dependent increases of rat locomotion. Investigatory behaviors such as holepokes and rearings were suppressed by (+)MDMA. Pretreatment with the selective 5-HT uptake inhibitors fluoxetine, sertraline and zimelidine inhibited (+)MDMA-induced locomotor hyperactivity but failed to antagonize the reduction of holepokes and rearings. Because 5-HT uptake inhibitors have been found previously to block the MDMA-induced release of 5-HT in vitro, and because fluoxetine was found to have no effect on (+)amphetamine-induced hyperactivity, the present results suggest that (+) MDMA-induced locomotor hyperactivity is dependent on release of endogenous 5-HT. Additionally, prior depletion of central 5-HT with p-chlorophenylalanine partially antagonized the (+)MDMA-induced hyperactivity, although catecholamine synthesis inhibition with alpha-methyl-p-tyrosine did not block the effects of (+)MDMA. Taken together, these studies suggest that (+)MDMA increases locomotor activity via mechanisms that are dependent on the release of central 5-HT and that are qualitatively different from the mechanism of action of (+)amphetamine.  相似文献   
93.
A 20-year-old white male was initially suspected clinically and pathologically of having an acute lymphoblastic leukemic process because of fatigue, severe anemia, thrombocytopenia, a leuko-erythroblastic peripheral blood picture, and a diffusely infiltrated bone marrow. Subsequent review of the bone marrow material indicated cytologic features consistent with either an embryonal, undifferentiated small cell mesenchymal malignancy or reticulo-endothelial malignancy. Ultimately, the electron microscopic (EM) study of the tumor proved to be diagnostic of rhabdomyosarcoma. An extensive search for a primary site of rhabdomyosarcoma did not show any lesion, although the genitourinary region was clinically suspected. The clinical course was a rapidly downhill one with extensive bone and CNS involvement. The patient died 5 months later. An autopsy permit was not obtained. This case emphasizes the occasional tendency of rhabdomyosarcoma to masquerade as a hematopoietic malignancy at the time of presentation and the usefulness of EM study in confirming a diagnosis.  相似文献   
94.
AimsTo compare the clinical utility of contrast enhanced magnetic resonance imaging (MRI) to ultrasound (USS) and computed tomography (CT) in focal hepatic lesions (FHLs)MethodsThis retrospective study analysed 125 consecutive iron oxide enhanced (SPIO) MRI.ResultsMRI made a difference in 74% of patients who had USS and in 42% of patients who had a CT scan. In suspected cancer, MRI changed diagnosis in 58% and 37% (13/35), respectively.ConclusionsMRI is superior to other noninvasive imaging modalities for lesion identification and characterisation.  相似文献   
95.
SUMMARY Four cases of primary meningococcal conjunctivitis in children are reported. This represents an incidence of 2% of patients presenting with conjunctivitis to a paediatric A&E department. All were initially treated with topical chloramphenicol, followed by systemic rifampicin once the diagnosis had been established. No ocular or systemic complications developed, nor recolonisation of the conjunctiva or colonisation of the nasopharynx at follow-up (1–2 years).  相似文献   
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97.
SUMMARY In this test a course of 4 drops twice a day for 5 days of ear wax solvents, a cerumenolytic, sodium bicarbonate, or sterile water significantly increased the clearance of wax from ears by natural expulsion and eliminated the requirement for ear syringing in 50% of cases.  相似文献   
98.
99.
In the past 3 years there have been five further cases, in additionto one case reported in 1985, of Creutzfeldt-Jakob disease inrecipients of human growth hormone in the United Kingdom. Theclinical findings of two of these cases are described, demonstratinga typical presentation with a predominantly cerebellar syndromeat onset which is not commonly a presenting feature of sporadicCreutzfeldt-Jakob disease. In one case a 99mTc hexamethylpropylenaminesingle photon emission tomographic scan showed marked impairmentof tracer uptake in the basal ganglia and cerebral cortex ata time when the clinical picture was predominantly cerebellar.This technique may be useful in early diagnosis. In the othercase post mortem examination of the brain showed prominent amyloiddeposition in the cerebellum, which has not been described previouslyin pituitary-hormone related Creutzfeldt-Jakob disease. Thepreviously published cases of growth hormone-related Creutzfeldt-Jakobdisease are reviewed and reasons for the particular clinicalpattern seen are discussed.  相似文献   
100.
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