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In the course of 1 year at a tertiary cancer center, 3 patients (2 men; 1 woman; age 51-75 years) were seen in neurological consultation (1.5% of all consultations). Clinical course in all patients was of a progressive neurologic disorder not consistent with either a primary or secondary malignancy. Magnetic resonance (MR) imaging was most informative with respect to diagnosis and subsequent management. Brain biopsy was performed in all patients to assist in both diagnosis and prognostication. All patients were determined to have progressive multifocal leukoencephalopathy (PML) by brain biopsy.  相似文献   
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Background: Tyrosine protein kinase proteins exert a prominent control on signaling pathways and may couple rapid events, such as action potential and neurotransmitter release, to long-lasting changes in synaptic strength and survival. Whether anesthetics modulate tyrosine kinase activity remains unknown. The aim of the current study was therefore to examine the effects of intravenous and volatile anesthetics on the phosphorylation of focal adhesion kinase (pp125FAK), a functionally important nonreceptor tyrosine kinase, in the rat hippocampus.

Methods: Phosphorylation of pp125FAK was examined in hippocampal slices by immunoblotting with both antiphosphotyrosine and specific anti-pp125FAK antibodies. Experiments were performed in the absence (control) or presence of various concentrations of pharmacologic or anesthetic agents or both.

Results: Clinically relevant concentrations of thiopental, propofol, etomidate, isoflurane, sevoflurane, and desflurane induced a concentration-related increase in tyrosine phosphorylation. In contrast, ketamine (up to 100 [mu]m) and the nonimmobilizer F6 (1,2-dichlorohexafluorocyclobutane, 25 [mu]m) did not significantly affect pp125FAK phosphorylation. The anesthetic-induced increase in pp125FAK phosphorylation was blocked by GF 109203X, RO 318220, and chelerythrin (100 [mu]m), three structurally distinct inhibitors of protein kinase C and U 73122 (50 [mu]m), an inhibitor of phospholipase C. The propofol- and isoflurane-induced increase in pp125FAK phosphorylation was reversible and showed nonadditivity of effects with phorbol 12-myristate 13-acetate (an activator of protein kinase C, 0.1 [mu]m). In contrast, ketamine (up to 100 [mu]m), MK801 (10 [mu]m, an N-methyl-d-aspartate receptor antagonist), bicuculline (10 [mu]m, a [gamma]-aminobutyric acid type A receptor antagonist), and dantrolene (30 [mu]m, an inhibitor of the ryanodine receptor) were ineffective in blocking anesthetic-induced activation of tyrosine phosphorylation.  相似文献   

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Laparoscopic hysterectomy   总被引:1,自引:0,他引:1  
Summary Thirty-three patients were selected for laparoscopic hysterectomy and operated on in the Department of Obstetrics, Gynecology and Reproductive Medicine of Clermont-Ferrand University Hospital. Surgical techniques included blunt dissection with scissors and bipolar coagulation to achieve hemostasis. A case was considered successful when all the uterine vessels were treated by laparoscopy. Twenty-four cases were completed laparoscopically (72.7%). None of these patients had postoperative bleeding; 22 had an uneventful postoperative recovery. Nine procedures were converted to laparotomy (27.3%), five because of a difficult or unsatisfactory hemostasis. We conclude that in selected cases, a total hysterectomy can be performed safely by experienced laparoscopists. Further technological progress is necessary to make this procedure more acceptable. Its value as compared to the others will have to be demonstrated.  相似文献   
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F Sris  I Marc 《Thorax》1994,49(6):562-566
BACKGROUND--A study was performed to evaluate the effect of discontinuation of nasal continuous positive airway pressure (NCPAP) treatment on snoring characteristics. METHODS--Eighteen non-apnoeic snoring subjects were randomly allocated to either a no treatment control group or an NCPAP treatment group. The control group was studied twice (baseline and day 30 of follow up). In the NCPAP group the level of NCPAP that abolished snoring was determined and part abolished snoring was determined and patients were placed on NCPAP every night for one month. A sleep study was performed on the first night without NCPAP after completing 30 days of treatment (follow up 1). A fourth polysomnographic study was performed 8-10 days after NCPAP was stopped (follow up 2) in six subjects. RESULTS--In both groups total sleep time (TST) and sleep architecture remained unchanged at the different visits. Baseline snoring characteristics in the two groups were similar. In the control group the mean (SE) number of snoring episodes/hour of sleep (snoring index) and the percentage of TST > 60 decibels (dB) were 380 (36)/h and 11.1 (2.0)% TST respectively at baseline, and was unchanged at follow up. In the NCPAP group the snoring index decreased from 387 (50)/h to 320 (57)/h after NCPAP therapy, but the % TSTS > 60 dB decreased from 10.3 (1.8)% to 7.4 (1.5)%. The snoring index and intensity returned to baseline values at follow up 2 (374 (74)/h, 9.8 (2.1)% TST). Changes in snoring characteristics could not be explained by changes in body position between the different sleep studies. CONCLUSIONS--NCPAP improves snoring but this effect is lost soon after stopping treatment.  相似文献   
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