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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.
J D Pfeifer 《Clinical neuropathology》1991,10(5):232-236
Diastematomyelia is a congenital dysraphism of the spinal cord in which the affected segment is longitudinally divided by a band of fibrous tissue, cartilage, or bone. Diastematomyelia has been well described in the cervical, thoracic, lumbar, and sacral spinal cord; this paper presents a case involving the basicranium. Based on the early embryologic development of the basicranium and brain, this case demonstrates that the same mechanisms proposed as the origin of spinal diastematomyelia may also operate at a more cephalad level. 相似文献
4.
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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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.
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
8.
Mariana Diniz Bisi Santos Arthur Braga Pfeifer Marcos Rogério Pupo Silva Claudio Luiz Sendyk WIlson Roberto Sendyk 《Journal of applied oral science : revista FOB》2007,15(2):148-151
One of the causes of implant failures in cemented implant-retained prostheses is the fracture of abutment screw or UCLA abutment. This article reports a case of simultaneous fracture of two UCLA abutments screws occurring in an implant-supported prosthesis placed in the mandibular molar region. The fractured structures were examined under scanning electron microscopy to investigate the probable causes of the failure, which were not related to failures on materials or fabrication of the screws, but rather were due to shear forces. The misfit in cemented prostheses may be the most likely cause of shear force generation. 相似文献
9.
Influence of Electromagnetic Fields on Function of Automated External Defibrillators 总被引:3,自引:2,他引:1
Roman Fleischhackl MD Florian Singer MD Wolfgang Nitsche PhD MSc Eng Guenther Gamperl MSc Engineering Bernhard Roessler MD Jasmin Arrich MD Sabine Fleischhackl MD Heidrun Losert MD Fritz Sterz MD Martina Mittlboeck PhD MSc Klaus Hoerauf PhD MD 《Academic emergency medicine》2006,13(1):1-6
Objectives: In this study, the authors tested whether electromagnetic interference (EMI) is able to impair correct electrocardiogram analysis and produce false‐positive shock advice from automated external defibrillators (AEDs) when the true rhythm is sinus. Methods: Nineteen healthy subjects were used to test five AEDs available on the Austrian market in a prospective, open, and sequence‐randomized study. The primary outcome variable was the absolute number of shocks advised in the presence of EMI. The secondary outcome was the number of impaired analyses caused by incorrectly detected patient movements or electrode failure. Results: Of 760 tests run, 18 (2.37%) cases of false‐positive results occurred, and two of five AEDs recommended shocks in the presence of sinus rhythm. Of 760 tests run, no electrode failures occurred. There were 27 occurrences (3.55%) of motion detected by an AED in the presence of strong electromagnetic fields. Conclusions: AED models differ in their response to EMI; it may be useful to consider specific safety requirements for areas with such fields present. Working personnel and emergency medical services staff should be informed about potential risks and the possible need for patient evacuation before AEDs are attached and shock recommendations are followed. 相似文献
10.