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71.
Wolfgang M Boer 《Practical procedures & aesthetic dentistry》2007,19(4):243-7; quiz 248
Aesthetics are as valuable in the posterior region as they are in the anterior. While the former is sometimes overlooked due to the limited visibility of posterior teeth, it is important that the clinician follow guidelines to ensure a high-quality restoration in this region. Restoring posterior teeth with direct resin can be accomplished through conservative and aesthetic treatment; however, it can also be challenging and time consuming to achieve exceptional aesthetics. Highlighting the importance of occlusal anatomy to the success of a direct resin restoration, this presentation outlines requisites to achieve this result. Learning Objectives: This article discusses guidelines for the aesthetic buildup of posterior restorations with direct resin techniques. Upon reading this article, the reader should Realize how the aesthetics of posterior restorations can be enhanced through the application of intensive composite shades. Understand the importance of occlusal design when building the restoration. 相似文献
72.
The stability of implanted artificial joints is limited. One main factor for this is the change of the bone tissue near the implant. Therefore we studied femura with stem endoprostheses derived from autopsy. All specimens were cut in horizontal and longitudinal sections. X-rays were made of all sections. Then the specimens were embedded undecalcified and ground to 10 microns. The wellknown phenomenons at the bone cement border were found too. Direct bone cement contact is about 5%. The 4 studied femura show a higher porosity of cortical bone as controls. The loss of cortical bone is up to 40% after 55 months. There is a correlation between new load situation and the localisation of bone loss. 相似文献
73.
Dystonia is a common movement disorder which is thought to represent a disease of the basal ganglia. However, the pathogenesis of the idiopathic dystonias, i.e. the neuroanatomic and neurochemical basis, is still a mystery. Research in dystonia is complicated by the existence of various phenotypic and genotypic subtypes of idiopathic dystonia, probably related to heterogeneous dysfunctions.In neurological diseases in which no obvious neuronal degeneration can be found, such as in idiopathic dystonia, the identification of a primary defect is difficult, because of the large number of chemically distinct, but functionally interrelated, neurotransmitter systems in the brain.The variable response to pharmacological agents in patients with idiopathic dystonia supports the notion that the underlying biochemical dysfunctions vary in the subtypes of idiopathic dystonia. Hence, in basic research it is important to clearly define the involved type of dystonia.Animal models of dystonias were described as limited. However, over the last years, there has been considerable progress in the evaluation of animal models for different types of dystonia.Apart from animal models of symptomatic dystonia, genetic animal models with inherited dystonia which occurs in the absence of pathomorphological alterations in brain and spinal cord are described.This review will focus mainly on genetic animal models of different idiopathic dystonias and pathophysiological findings. In particular, in the case of the mutant dystonic (dt) rat, a model of generalized dystonia, and in the case of the genetically dystonic hamster (dtsz), a model of paroxysmal dystonic choreoathetosis has been used, as these show great promise in contributing to the identification of underlying mechanisms in idiopathic dystonias, although even a proper animal model will probably never be equivalent to a human disease.Several pathophysiological findings from animal models are in line with clinical observations in dystonic patients, indicating abnormalities not only in the basal ganglia and thalamic nuclei, but also in the cerebellum and brainstem. Through clinical studies and neurochemical data several similarities were found in the genetic animal models, although the current data indicates different defects in dystonic animals which is consistent with the notion that dystonia is a heterogenous disorder.Different supraspinal dysfunctions appear to lead to manifestation of dystonic movements and postures. In addition to increasing our understanding of the pathophysiology of idiopathic dystonia, animal models may help to improve therapeutic strategies for this movement disorder. 相似文献
74.
Martin Krause Wolfgang Fogel Volker Tronnier Sabine Pohle Konstanze H?rtnagel Ute Thyen Jens Volkmann 《Movement disorders》2006,21(12):2255-2257
Pantothenate kinase-associated neurodegeneration (PKAN) is a rare autosomal recessive disorder with onset in childhood and rapid progression. There is no causative and insufficient symptomatic drug therapy. Deep brain stimulation (DBS) of the internal pallidum (GPi) has been reported to improve motor function. Most case reports, however, are limited to short observational periods. The impact of DBS on the progression and life expectancy in PKAN is unknown. We present a 5-year outcome and video documentation of bilateral GPi-DBS of an adolescent patient suffering from genetically defined PKAN. 相似文献
75.
Alexandre Castro-Caldas Paul Delwaide Wolfgang Jost Marcelo Merello Adrian Williams Paolo Lamberti Miguel Aguilar Susanna Del Signore Pierre Cesaro 《Movement disorders》2006,21(4):500-509
Dopamine agonists have been recommended as early treatment for Parkinson's disease (PD), alone or combined with levodopa. Piribedil is a non-ergot selective D(2)/D(3) agonist with alpha(2) antagonist properties shown to be effective in the treatment of PD. This 12-month international, randomized, double-blind trial aimed to assess the efficacy of piribedil 150 mg versus bromocriptine 25 mg, in early combination with levodopa in Stage I to III PD patients. Motor efficacy was assessed using the Unified Parkinson's Disease Rating Scale (UPDRS III, Items 18-31) as improvement from baseline. Response rate was defined as a 30% improvement. Among the 425 randomly assigned patients, 178 were also included in a substudy on cognitive follow-up evaluated by a dysexecutive syndrome oriented battery. A relevant improvement in UPDRS III over the 12-month study duration was observed both in the piribedil and bromocriptine groups (-7.9 +/- 9.7 points from baseline versus -8.0 +/- 9.5; not significant [n.s.]) with a response rate of 58.4% and 55.3% (n.s.), respectively. Piribedil and bromocriptine resulted in similar improvement on all UPDRS III subscores. Piribedil patients required less levodopa dose increase than those on bromocriptine. Cognitive performance remained generally unchanged in both groups, with a significant effect of piribedil limited to the Wisconsin Card Sorting Test. An overall good tolerability of piribedil was observed. Early combination of piribedil 150 mg with levodopa resulted in significant long-term improvement of all motor symptoms in PD patients insufficiently controlled by levodopa alone. Taking into account both efficacy and acceptability in the long-term, piribedil proved in this bromocriptine controlled study to be an effective and safe treatment for PD. 相似文献
76.
Fumiharu Kimura R. Glenn Smith Osvaldo Delbono Okot Nyormoi Toni Schneider Wolfgang Nastainczyk Franz Hofmann Enrico Stefani Stanley H. Appel 《Annals of neurology》1994,35(2):164-171
Sporadic amyotrophic lateral sclerosis is an idiopathic human degenerative disease of spinal cord and brain motor neurons. Prior studies demonstrated that most patients with amyotrophic lateral sclerosis posses immunoglobulins that bind to purified L-type voltage-gated calcium channels, that titers of anti–voltage-gated calcium channel antibodies correlate with disease progression rates, and that amyotrophic lateral sclerosis patient-derived antibodies (ALS IgG) produce electrophysiological changes in the function of voltage-gated calcium channels. Using Western transfer immunoblots and enzyme-linked immunosorbent assays, the calcium ionophore–forming α1 subunig of the voltage-gated calcium channel is now identified as the major voltage-gated calcium channel antigen to which ALS IgG binds. Additionally, the binding of an L-type voltage-gated calcium channel α1 subunit–directed monoclonal antibody, which itself mimics the effects of ALS IgG on skeletal muscle voltage-gated calcium channel currents, is selectively prevented by preaddition of ALS IgG. Voltage-gated calcium channel–binding IgG from patients with Lambert-Eaton myasthenic syndrome appears to be differentiated from ALS IgG by the reactivity of the former to both α1 and β subunits of the calcium channel. These assays provide further evidence linking amyotrophic lateral sclerosis to an autoimmune process, and suggest one means to differentiate immunoglobulins from patients with amyotrophic lateral sclerosis from those of patients with another autoimmune disease expressing calcium channel antibodies. 相似文献
77.
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79.
M Jütte S Klein D Katenkamp W Vogel W G?tz R Woytinas 《Klinische Monatsbl?tter für Augenheilkunde》1992,200(6):674-677
The results with two new enucleation prothesis made of Bioverit are presented. After unilateral enucleation 14 rabbits received bioreactive, 14 rabbits biocompatible and 9 rabbits nylon prostheses. Implantation periods: 1-13 months. The tissue surrounding of the prostheses was studied histologically, the ceramic electron microscopically. Of 28 ceramic prostheses, 26 were adapted very well. Bioverit ist excellently suited as orbital prosthetic material, even half-open implants are possible. 相似文献
80.
Dieter Ebert Andrea Jaspert Harumi Murata Wolfgang P. Kaschka 《Psychopharmacology》1995,118(2):223-225
The hypothesis was tested that an initial lithium-tricyclic antidepressant (TCA) combination has a better antidepressant effect than standard TCA treatment in non-refractory depression at the beginning of an episode. Twenty bipolar melancholic type depressed inpatients under lithium-TCA treatment were compared with 20 patients with the same diagnosis and TCA-placebo treatment for 5 weeks under double-blind conditions. All patients were male. Initial lithium-TCA treatment reduced depressive symptoms significantly more than antidepressant treatment with TCA and placebo after 5 weeks, but not in weeks 1 or 2. It can be concluded that lithium augmentation of TCA treatment should be started even at the beginning of antidepressant TCA treatment to provide a better treatment response in those patients who will profit from long-term lithium prophylaxis, e.g. bipolar patients with melancholic type depression. 相似文献