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81.
Venous leg ulcers derived from tissue destruction is the consequence of a chronic inflammatory process that produces pain and physical disability, diminishing quality of life in patients. In this work, Lassar ointment and lyophilized collagen‐polyvinylpyrrolidone were administered separated each on one half in the same ulcer to 9 patients at the beginning and every 4 days. On day 16, all patients were auto‐grafted with partial thickness skin. Granulation tissue and graft integration were assessed clinically during 3 months. Inflammatory infiltrate, type I and III collagens, elastic fibers, alkaline phosphatase as well as blood vessels were evaluated histologically or histochemically in biopsies taken at the beginning and 16 days after the local treatment. Clinically and morphologically, both treatments demonstrated appropriate granulation tissue promotion and optimal graft integration since the beginning. Nevertheless, in Lassar ointment treated group regionalization of alkaline phosphatase activity was observed, as well as the presence of granuloma in 2 of the 9 patients. In conclusion, Lassar ointment or lyophilized collagen‐polyvinylpyrrolidone are two different promoters of granulation tissue in venous leg ulcers, however Lassar ointment has the capability to produce granuloma and an exacerbated immune response; in consequence, ulcer recidivism could be present, may be due to mineral deposits in the wound.  相似文献   
82.
Rotator cuff tears are increasingly treated arthroscopically, preferentially with suture anchors since a stable anchorage in bone is possible, simple and rapid. However, the restricted view, especially with longer operating times, conceals a danger of misplacement. Such risks can be determined rapidly with experience and should be corrected as soon as possible, e.g. through a change to open procedures. In our case report, the migration of a metal anchor could be corrected in a later operation and a revision of the re-rupture was then carried out using mini-open technique.  相似文献   
83.
A new method to study permeation of gases in proton conducting membranes using a cylindrical microelectrode is presented. The focus of this work was to develop an in-situ method to study transport properties of hydrogen and oxygen close to real fuel cell operating conditions. The gas permeability is strongly affected by the change of water content in the membrane and it is therefore of advantage that, by using this method, measurements can be carried out over a wide range of relative humidities. The numerical method makes it possible to separate the diffusion coefficient and the concentration of dissolved gas in the membrane and also allows kinetic limitations to be taken into account. Chronoamperometric measurements on Nafion® 117 were successfully evaluated numerically. Experiments at temperatures of 25 and 60 °C with respect to oxygen permeation and at 60 °C for hydrogen permeation at relative humidities in the range 30–94% are presented. The reproducibility of data was excellent when measuring with different microelectrodes on the same membrane sample, but differed when measuring on different samples. In general, the permeability increases with increasing temperature and relative humidity.  相似文献   
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Ohne Zusammenfassung  相似文献   
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Die 5-Jahres-überlebensrate von differenzierten Schilddrüsenkarzinomen ist generell sehr gut und betr?gt 80 – 95%. Hierbei bestehen Abh?ngigkeiten zum Alter des Patienten [15], zum prim?ren Tumorstadium, zur histologischen Differenzierung und zum Ausma? der region?ren und Fernmetastasierung [6]. Patienten mit Tumorfreiheit haben ebenfalls eine bessere Prognose gegenüber denen mit einem Resttumor. Dies spricht für ein konsequentes Vorgehen beim Prim?reingriff mit Thyreoidektomie und Entfernung der Lymphknoten des zentralen Kompartments. Stadienadaptiert schlie?t sich eine Radiojodtherapie oder die Kombination mit einer externen Radiatio an. Bei der Reoperation differenzierter Schilddrüsenkarzinome mu? zwischen der individuellen Prognose des Patienten, dem Ziel der Operation und der postoperativen Morbidit?t/Mortalit?t entschieden werden. Aufgrund des hohen Risikos sollten diese Operationen in Zentren durchgeführt werden, so da? postoperative Komplikationen (permanente Recurrensparese/Hypoparathyreoidismus) vertretbar gering gehalten werden k?nnen (Tabelle 11). Dennoch sollte nicht au?er Acht gelassen werden, da? individuell bei differenzierten Schilddrüsenkarzinomen im Stadium pT1 auch ein eingeschr?nkt radikales Vorgehen (Hemithyreoidektomie) ohne Verschlechterung der Prognose m?glich scheint. Strenge Nachuntersuchungsergebnisse und Ergebnisse weiterer klinischer Studien müssen hierzu abgewartet werden.  相似文献   
87.
Camptodactyly is a flexion deformity of the proximal interphalangeal joint. Because of unsatisfactory results, treatment is not recommended for mild deformities, and in severe deformities surgery has been disappointing. A specially designed external fixator providing gradual distraction was used in a severe case. With this mildly aggressive method, an acceptable result was obtained. Received: 5 June 1997/Accepted: 2 February 1998  相似文献   
88.
Various neocortical areas from four females aged 16–24 years with Rett syndrome (RS) were investigated and compared with brains of therapy-resistant partial epilepsy (TRPE) patients (18–25 years), infantile autism (IA), and control brains (24 and 58 years). The cytoarchitecture of area 10 (frontal), area 21 (temporal), area 4 (primary motor cortex), and area 17 (primary visual cortex) was studied by the combined Klüver-Barrera (luxol fast blue and cresyl violet) standard procedure. Autofluorescence of lipofuscin, immunofluorescence of synaptic vesicle proteins [synaptophysin (p38)] and lectin-stained (Wisteria floribunda agglutinin) perineuronal nets (PNs) were studied in the cortices using dual-channel confocal laser scanning microscopy. The brains of RS females show various types of morphological/cytoarchitectonical abnormalities of single pyramidal neurons in layers II–III, and V–VII of different cortical areas. The abnormalities include mild losses of pyramidal neurons, more pronounced in layers II and III than in layers V and VII, and more evident in frontal and temporal areas than in the visual cortex. Microdysgenesis, including abnormalities due to neuronal migration disorders, was not found in RS, in contrast to the observations in TRPE patients, strongly indicating that RS is not a neuronal migration disorder. Lipofuscin distribution was normal but amounts were lower in RS cases than in control and TRPE brains. PNs were less expressed in cortices of the IA case, but were clearly overexpressed in the motor cortex of RS. Quantitative analysis of p38 showed a decrease in the area occupied by p38 immunoreactivity by 20–40% in RS compared with controls. It is concluded that RS could best be explained by a postnatal synaptogenic developmental deficiency; the basic defect, however, is still completely unknown. Received: 26 February 1996 / Revised, accepted: 11 July 1996  相似文献   
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