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171.
Objective: The aim of the study was to investigate whether or not esuprone binds substantially to MAO-A in the human brain. Methods: In a randomised double-blind placebo-controlled study 16 male healthy volunteers were examined␣with positron emission tomography (PET) with [11C]harmine. Eight of the volunteers were given daily doses of 800 mg esuprone, four were given bi-daily doses of 300 mg moclobemide, and four volunteers were given placebo tablets. PET was performed before initiation of a 7-day treatment period. On day 7, one investigation was made immediately before administration of the drug, representing 23 h after the previous day's treatment for esuprone and 11 h after the last tablets of moclobemide. Further investigations were made 4 h and 8 h after the morning dose on day 7. Results: PET showed a high degree of binding of [11C]harmine, a high-affinity ligand for MAO-A, before the start of treatment, and a marked and similar reduction after treatment with esuprone and moclobemide. A slight tendency for normalisation of enzyme binding was observed at the last time point. In the placebo group no change was observed. Plasma kinetics of esuprone showed a rapid elimination with a half-life of about 4 h. Conclusion: The study demonstrates that esuprone was comparable to moclobemide in its effect on MAO-A inhibition in the brain at the doses given. This is an illustration of the potential of PET to monitor drug effects directly on target biochemical systems in the brain in human volunteers, and the possibility of using these data, rather than pharmacokinetic data, for the determination of dosing intervals. Received: 21 August 1996 / Accepted in revised form: 22 November 1996  相似文献   
172.
173.
A total of 186 blood samples from 24 HIV-1 seropositive hemophiliac patients, monitored every four months for 29 months, were investigated for the presence of viral antigen in plasma. In addition, peripheral blood mononuclear cells (PBMC) were cultured for HIV-1, using normal PBMC as a target for replication. Antigenemia was detected in 51 % of the patients and from PBMC in 87.5 % of the patients. The incidence of HIV isolation in asymptomatic patients (42.8 %) was similar to that found in symptomatic patients (51.4 %). Patients with opportunistic infections had a higher incidence of lymphocytic viremia (p<0.05). Plasma viremia was closely associated (p<0.05) with low CD4+ counts and infection progression. The persistence of antigenemia was also a marker of a poor clinical course. In treated patients, plasma viremia was the marker that better correlated with the clinical course, and it did not appear during the first nine months of therapy. Zidovudine doses of >500 mg/day significantly lowered the appearance of antigenemia and lymphocytic viremia (p<0.05).  相似文献   
174.
Acute ischaemia of the vertebrobasilar circulation leads to a variety of clinical manifestation and is mostly due to cardiogenic or artery-to-artery embolism. We describe four neurological emergency situations involving vertebrobasilar artery aclusion of other origins: basilar migraine, extrinsic compression by rheumatoid inflammatory tissue, generalized vasculitis in subacute rheumatic fever and basilar artery dissection. The differential diagnosis of acute vertebrobasilar artery occlusion may have an important impact on patient management.  相似文献   
175.
176.
The author observed 315 patients with the amebic liver abscess. Of them in 134 (42.5%), the renal syndrome was diagnosed. The kidney damage had the course of the secondary pyelonephritis type, or in the form of a toxic kidney. On the basis of clinico-laboratory analysis, the author distinguishes the mild, moderate and severe degrees of kidney damage, recommends an adequate transfusion-infusion, antibacterial and specific therapy.  相似文献   
177.
Authors describe a case of isolated posttraumatic neuropraxy of the musculocutaneous nerve. With the presentation of this very rare case attention is called, based on literary date, to the fact that the above injury can be mixed with the distal tendon rupture of the biceps.  相似文献   
178.
The principles of treatment of tibial pseudoarthroses complicated by skin and soft tissue loss with the use of cancellous bone grafts from posterolateral approach to the tibia by Harmon method were discussed. The detailed surgical technique was presented. Management of 3 patients that resulted in bone union was described.  相似文献   
179.
This report provides transmission electron microscopic observations on the early pathogenesis of persistent hyperplastic tunica vasculosa lentis/persistent hyperplastic primary vitreous (PHTVL/PHPV) in affected canine fetuses at days 28-44 postcoitum. The retrolental tissue by which this anomaly is characterized consists of loosely arranged fibroblasts in a randomly oriented meshwork of collagenous fibrils. Some of these cells contain melanosomes at day 44. In one day-44 eye, cells of neuroectodermal origin (Müller cells; fibrous astrocytes) were observed. From day 37 onward, the posterior subcapsular part of the lens contains rounded, increased intercellular spaces, resembling vacuoles, which deform the shape of the lens fibers. The posterior lens capsule develops normally until day 30. From day 35 onward the capsule has an amorphous ultrastructure, as opposed to the clearly laminated ultrastructure in reference eyes at day 35. In addition, the capsule's thickness increases until day 35, and, instead of growing thicker, decreases thereafter. Based on these results, it is hypothesized that a primary metabolic disorder in the lens fibers, subsequently leading to the formation of an abnormal posterior lens capsule, constitutes the primary defect in the sequence of events leading to PHTVL/PHPV.  相似文献   
180.
Responses to a standardized respiratory symptom questionnaire, spirometry, and cross-shift decreases in lung function between 70 current employees of a polyvinylchloride (PVC) fabrication plant and a control group consisting of 48 men employed in a vegetable packing plant were compared. FEV1/FVC was significantly lower in the PVC workers. Cross-shift drops in Vmax75 of 15% or more were also more prevalent in the exposed group (p = .01). When examining the association between months of work within the exposed workforce and spirometric indices of airway obstruction, no relationship could be demonstrated. However, an inverse dose-response relationship was seen between level of FVC and duration of employment, suggesting a restrictive impairment. While the specific exposures have not been identified, it appears that employment in PVC fabrication may be associated with both obstructive and restrictive ventilatory effects.  相似文献   
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