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1.
Intramedullary nailing implants have now assumed the first place in the treatment of pertrochanteric fractures.The reasons for their popularity are their high fatigue strength and the minimally invasive surgical technique required for their use.These advantages are of great benefit to the mainly geriatric and frequently multitraumatized patients concerned.The main device in this implant group is the gamma nail, which was originally developed by Grosse and Kempf. The gamma nail yielded results superior to those obtained with the dynamic hip screw, which had been the standard so far, especially when it was used in the treatment of unstable fractures.Although there was some vigorous debate over the original principles of the gamma nail, the current system is widely accepted and is available in different variants.However,owing to the high complication rate when the system was first introduced, the original gamma nail acquired the reputation of being an implant whose use made high demands.The critical analysis of implant-specific problems associated with the original gamma nail resulted in improvements to the implant and the instruments, with a noticeably reduced complication rate and better surgical technique.This article describes its current state of development.The various components are discussed individually. The results of our own investigation appear at the end of the report, reflecting this development process. 相似文献
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3.
Maximum anchorage often presents a problem that is difficult to solve during orthodontic tooth movement. Stationary, skeletal anchorage can be achieved in a simple, minimally-invasive manner, and unwanted tooth movements in opposite directions can be prevented by using transmucosally-inserted bone screws.Our initial experience using the FAMI screw as an orthodontic micro-implant proved to be clinically and histologically successful. 相似文献
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6.
Frank G. Holz Caren Bellmann Heimo Steffen Bernhard Nölle Jens Huober Hermann Krastel Evangelos Alexandridis 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1997,94(5):337-342
Fragestellung: Die Karzinomassoziierte Retinopathie (CAR) stellt ein seltenes paraneoplastisches Syndrom dar, das bislang
am h?ufigsten bei kleinzelligen Bronchialkarzinomen beschrieben wurde. Wir berichten über 3 Patientinnen mit CAR in Gegenwart
eines Mammakarzinoms bzw. eines Karzinoids der Cervix uteri.
Patienten und Methode: Es wurden biomikroskopische, perimetrische, angiographische und elektrophysiologische Befunde erhoben.
Au?erdem erfolgte eine Testung der Immunreaktivit?t der Seren an humaner Retina.
Ergebnisse: Die Befunde umfa?ten ringf?rmige Gesichtsfelddefekte mit statokinetischer Dissoziation und eine pathologische
St?bchen- und Zapfenantwort im ERG. Bei 1 Patientin wurde immunhistochemisch eine Reaktion im Bereich der Photorezeptorinnensegmente,
der ?u?eren K?rnerschicht sowie der ?u?eren plexiformen Schicht bei fehlendem Nachweis von Antik?rpern gegen Recoverin gefunden.
Diskussion: Neben dem kleinzelligen Bronchialkarzinom k?nnen auch andere Prim?rtumoren mit einer CAR vergesellschaftet sein.
Der Nachweis von retinalen Autoantik?rpern unterstützt die Annahme einer tumorinduzierten Immunantwort aufgrund der Expression
identischer Epitope durch die Tumorzellen. Dabei kommen offensichtlich verschiedene retinale Proteine als Autoantigene in
Betracht.
相似文献
7.
Assoc. Prof. Dr. Andrea Wichelhaus Richard Haas Franz-Günter Sander Joachim-Franz Kreidler 《Journal of orofacial orthopedics》1998,59(6):340-351
For functional rehabilitation and improvement of mandibular mobility, 14 patients with dislocated collum or collum fracture dislocations were treated with a spring activator after surgical-conservative treatment. With an interincisal distance of<12 mm, therapy was started with a loop spring. The average age of the patients was 26.6 years. Eight patients showed additional traumatic injuries, 2 patients were seriously polytraumatically injured. The clinical investigations referring to the maximum mouth opening and maximal interincisal distance resulted in a good to very good functional rehabilitation in all cases. The average maximal interincisal distance of 31.7 mm at the beginning of the spring activator therapy could be increased to 47.3 mm. The largest increase of the maximal interincisal distance was observed after 4 weeks of therapy. The type of reaction, however, differed interindividually. Three patients showed a spontaneous improvement of the interincisal distance within the first 2 to 3 weeks of removal of intermaxillary fixation, whereas 7 patients whowed no improvement or only slightly improved values until insertion of the spring activator. An enlargement of the interincisal distance could be achieved in almost every patient within a relatively short period of time despite a drastically reduced mouth opening. Consequently, because of its mode of action in the form of a neuromuscular influence, the spring activator is especially suitable for the functional rehabilitation of patients with fractures of the condylar process. 相似文献
8.
Katalin Vehmeyer Tibor Hajto Katarina Hostanska Stefan Knemann Holger Lser Reinhard Saller Bernhard Wrmann 《European journal of haematology》1998,60(1):16-20
Abstract: The galactoside-specific plant lectin, Viscum album agglutinin (VAA-I) increases cellular parameters of natural host defence. It also binds to a variety of haematopoietic cells, including progenitors. We investigated whether VAA-I has a stimulatory effect on haematopoietic progenitor cells. Peripheral blood progenitor cells from 7 healthy volunteers were cultured in a colony assay with VAA-I plus erythropoietin (EPO) and stem cell factor (SCF). At 50 pg/ml VAA-I induced a significant increase in the cytokine-dependent clonogenic growth (52% in median, p<0.05). In another set of experiments purified CD34+ cells were isolated from the bone marrow aspirate of 4 patients with non-metastatic breast cancer using fluorescence-activated cell sorting. Binding to CD34+ cells was demonstrated by using directly fluorescence-conjugated VAA-I. Co-incubation with d -galactose significantly abrogated this effect. CD34+ cells were cultured in the presence of EPO, SCF, interleukin-3, granulocyte/monocyte colony-stimulating factor and granulocyte colony-stimulating factor. VAA-I alone had no measurable effect on the clonogenic growth of the isolated cells. However, at concentrations of 100 and 250 pg/ml VAA-I increased the cytokine-dependent proliferation and differentiation of CD34+ cells by a median of 75 and 85%, respectively. The results show that VAA-I binds to haematopoietic progenitor cells and has a co-stimulatory effect on their proliferation. 相似文献
9.
Bernhard R. Slaap Irene M. van Vliet Herman G. M. Westenberg Johan A. Den Boer 《Psychopharmacology》1996,127(1-2):353-358
Little is known about biological predictors of treatment response in panic disorder (PD). In the present study heart rate,
blood pressure, plasma cortisol and plasma MHPG were investigated at baseline in a sample of 44 PD patients as possible predictors
for nonresponse to treatment. We used a strict definition of nonresponse to find patients who did not respond at all after
12 weeks of treatment with brofaromine or fluvoxamine. Patients were considered nonresponders when they fulfilled two criteria:
they did not show a 50% reduction of agoraphobic avoidance and they still experienced panic attacks at endpoint. The variables
that differed significantly between the groups were used to predict nonresponse to drug therapy. Using this strict definition
of nonresponse, 15 patients (32.6%) were considered nonresponders. These patients were characterised by a higher plasma MHPG
concentration and a higher heart rate at baseline. These variables were subsequently used to predict nonresponse. 相似文献
10.
Sander Greenland 《Statistics in medicine》1993,12(8):717-736
Many epidemiologic investigations are designed to study the effects of multiple exposures. Most of these studies are analysed either by fitting a risk-regression model with all exposures forced in the model, or by using a preliminary-testing algorithm, such as stepwise regression, to produce a smaller model. Research indicates that hierarchical modelling methods can outperform these conventional approaches. I here review these methods and compare two hierarchical methods, empirical-Bayes regression and a variant I call ‘semi-Bayes’ regression, to full-model maximum likelihood and to model reduction by preliminary testing. I then present a simulation study of logistic-regression analysis of weak exposure effects to illustrate the type of accuracy gains one may expect from hierarchical methods. Finally, I compare the performance of the methods in a problem of predicting neonatal mortality rates. Based on the literature to date, I suggest that hierarchical methods should become part of the standard approaches to multiple-exposure studies. 相似文献