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21.
Treatment of a juvenile patient with a maxillary all-ceramic resin-bonded fixed partial denture: a case report. 总被引:1,自引:0,他引:1
Dietmar Weng Stefan Ries Ernst-Jürgen Richter 《Quintessence international, dental digest》2002,33(8):584-588
Treatment of juvenile patients with a missing maxillary incisor is difficult, because an implant cannot be placed until growth is completed. The other minimally invasive alternatives are also problematic: Removable dentures are rarely accepted by juvenile patients, and the conventional resin-bonded fixed partial denture often provides a poor esthetic result because the metal retainer causes the abutment teeth to lose their natural translucency and to become grayish. Moreover, the alveolar ridge defect makes it easy to identify the prosthesis in the pontic area. The present case report describes the prosthetic treatment of a juvenile patient who had lost a maxillary incisor to trauma. To avoid the disadvantages of conventional therapies, subepithelial connective tissue was grafted to reshape the alveolar ridge. The space was closed with an all-ceramic resin-bonded fixed partial denture. 相似文献
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23.
We present a new concept after Schultheis which is based on the results of experimental studies on cell cultures. Local chemoembolization in liver tumours including liver metastases is usually performed via the angiographic route. Embolisation of the most peripheral branches of the hepatic artery prevents early formation of collateral vessels. The method also comprises the additional infusion of cytostatic agents via the portal vein. The procedure is usually repeated after an interval of about four weeks. In this paper we will describe our method in liver metastases and present the preliminary results obtained from 19 patients treated to date. 相似文献
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25.
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
26.
To date microscopy and cultural isolation still remain the “gold standard” in the laboratory diagnostics of mycobacteria. Nucleic acid amplification techniques additionally enable a rapid and sensitive detection of Mycobacterium tuberculosis. However, bacterial growth is still required for species identification and susceptibility testing which should be performed from one of the first isolates of every patient and repeated after about 2 months if cultures are still positive. By means of DNA fingerprint techniques, the confirmation of transmission, of TB outbreaks, and also of laboratory cross-contamination is feasible. 相似文献
27.
G Barzen C Schubert W Richter D Calder M B?rwald H Eichst?dt R Felix 《Strahlentherapie und Onkologie》1992,168(12):732-737
We evaluated the role of thallium-201 single-photon emission-computed tomography (SPECT) in diagnosis, differential diagnosis and follow-up of 33 patients with primary brain tumors. 27 of 33 lesions were detectable by Tl-201 SPECT because only two of eight low-grade (grade 1 and 2) astrocytomas showed Tl-201 accumulation up to a tumor to nontumor ratio of 2.6. High grade (grade 3 and 4) astrocytomas showed Tl-201 accumulation in the range of 2.2 up to 13.0 and were different from low-grade astrocytomas. Noninvasive grading of astrocytomas is therefore possible, whereas differential diagnosis of oligodendrogliomas and astrocytomas or meningiomas was not possible with Tl-201. In the follow-up of six patients, we could demonstrate, that tumor progression is correlated with increasing and tumor regression with decreasing Tl-201 accumulations. This functional changing proceed morphological findings in CT. But vanishing of Tl-201 accumulation during therapy does not mean vanishing of tumor as could be demonstrated by follow-up. 相似文献
28.
The following article presents two new cases of a lipofibroma of the median nerve. This formation is a very rare benign tumor of peripheral nerve tissue. Up to now 30 cases have been reported in the literature and are reviewed in this article and are compared with the two cases reported. Besides the operative treatment, which made the neuropathological diagnosis possible, preoperative diagnosis has been extended by MNT-scans of the involved parts of the nerve. The noninfiltrating character of the tumor could be well recognized on these scans. The signal quality and the anatomical proximity to the median nerve made the diagnosis of a lipofibroma likely. By the postoperative histological reviews the diagnosis was confirmed in classic manner. The immunological marking of the S-100 protein showed a remarkable reduction of this protein in these peripheral nerve tumors. The two cases reported by us recapitulate the clinical history typically and describe symptoms and our treatment for the lipofibroma of the median nerve. 相似文献
29.
The Changing Faces of the Nutcracker Esophagus 总被引:3,自引:0,他引:3
Christine B. Dalton P.A.C. Donald O. Castell M.D. Joel E. Richter M.D. 《The American journal of gastroenterology》1988,83(6):623-628
Although the nutcracker esophagus, characterized by high amplitude peristaltic contractions with mean distal amplitude greater than 180 mm Hg, is the most common esophageal motility disorder associated with noncardiac chest pain, little is known about its natural history. Therefore, we reviewed the manometric tracings of 23 patients with the nutcracker esophagus who had an average of 4.6 studies during a mean period of 32 months. Ten age-matched volunteers with normal baseline manometry who had undergone multiple studies (mean 5.8) over a mean time span of 32 months served as controls. In the 17 nutcracker patients with three or more motility studies, the variability of mean distal amplitudes between studies was 41.9% +/- 4.1 (+/- SE) compared to 27.0% +/- 3.3 for the control subjects (p less than 0.01). Highest distal pressures were noted during the first study in 11 of 17 patients (65%) compared to two of 10 controls (20%). The consistency of the diagnosis of nutcracker esophagus varied considerably: four patients always had high amplitude pressures, three patients only had the nutcracker diagnosis on the initial study, and 10 patients intermittently had pressures in the nutcracker range. Overall, these 17 patients had the diagnosis of the nutcracker esophagus confirmed on only 54% of subsequent studies. Changes in motility patterns were intermittently seen in six of 23 patients: one diffuse spasm and five nonspecific motility disorders. None of the control subjects developed high amplitude contractions or changed their motility pattern on serial testing. The possible pathophysiological implications of the changing faces of the nutcracker esophagus are discussed. 相似文献
30.
An increasing number of patients desire body contouring surgery after massive weight loss, whether from bariatric surgery or a change in lifestyle. The fact that many body regions lose their elasticity and tissue-tension has led to stepwise treatments including abdominoplasty, thigh lift, buttocks and hip lift or liposuction. However, these procedures often do not treat the reason for the deformities. The lower body lift first described by Ted Lockwood in 1993 is a procedure that allows simultaneous skin resection and tightening of different regions including the abdomen, buttocks, hips, and thighs. In this article the authors present their 10-year experience with the body lift. Patient selection, technical details, pre- and postoperative care, complications, and expected results are all discussed. 相似文献