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21.
In a prospective study of the effect of postoperative radiation therapy for the prevention of reproliferation of membranes and recurrent proliferative vitreoretinopathy (PVR) two similar groups of patients with retinal detachment and PVR grade D1 to D3 in one eye were compared. Half the eyes (30) received a total dose of 3000 cGy after surgery; the other half remained untreated. After a followup of 6 months and 14 months or more (maximum 36 months) the anatomical and functional results of each group were compared. After 6 months in the unirradiated group 57% (17/30) remained attached and 43% (13/30) had detached again. In the irradiated group 63% (19/30) were attached and 37% (11/30) had detached. However, there was no statistically significant difference between the two groups (P=0.479, Fisher's Exact Test). After 14 months the number of cured and uncured eyes remained the same in the unirradiated group, while in four of the eyes in the irradiated group a later onset of reproliferation and detachment occurred (after 7, 8, 12 and 14 months, respectively). A final cure rate of 57% (17/30) was achieved in the unirradiated group and a 50% (15/30) cure rate in the irradiated group. Thus the failure rate was 43% (13/30) in the unirradiated group and 50% (15/30) in the irradiated group (P=0.473, Fisher's Exact Test). No side effects from the radiation were observed in any case and no radiation retinopathy occurred during an observation period of up to 3 years. The visual acuity of the cured treated and cured untreated eyes was similar in the two groups. From these results we conclude that immediate radiation treatment does not improve the long-term results and does not reduce the number of reoperations. In a considerable number of treated eyes the onset of reproliferation was delayed from 7 to 14 months, whereas in the untreated group reproliferation was always observed during the first 6 months. A combination of various antiproliferative and antiinflammatory therapies are needed to suppress recurrent PVR after succesful vitreoretinal surgery and to minimize the side effects of these treatments.Presented in part at the XVIIth Meeting of the Club Jules Gonin, 1–6 September 1990, Lausanne  相似文献   
22.
Zusammenfassung Die Typ I-Allergien gegen Latex sind in den vergangenen Jahren zu einem zunehmenden berufsdermatologischen Problem geworden, zumal mindestens 10% der Angestellten im Gesundheitswesen betroffen sind. In der Dermatologischen Klinik der Universit?t Erlangen-Nürnberg stieg die Anzahl der j?hrlich diagnostizierten Patienten mit Latexallergien von 1989 bis 1995 auf das 12fache, wobei der Anteil der schweren, generalisierten Formen der Erkrankung von 10,7% (1989/1990) auf 44% (1994/1995) zunahm. Unter den m?glichen Ausl?sern der Latexallergie (wasserl?sliche Proteine mit Molekulargewichten von 2 bis 200 kD) sind mindestens 5 Hauptproteine mit bereits bekannter Prim?rstruktur zu berücksichtigen. Zus?tzlich gibt es Hinweise für Markerproteine, die in bestimmten Risikogruppen geh?uft zur Ausl?sung spezifischer IgE-Antik?rper führen (z.B. 46 kD-Protein in medizinischen Berufen, 14,6 kD- und 27 kD-Proteine bei Kindern mit Spina bifida). Das Vorkommen von Kreuzreaktionen zwischen Latex und unterschiedlichen Früchten (besonders Avocado, Kiwi, Banane, E?kastanie) bei 60 bis 70% der Latexallergiker ist bei der allergologischen Abkl?rung und Beratung dieser Patienten zu beachten. Wesentliche Aspekte der Prophylaxe umfassen die konsequente Umstellung medizinischer Einrichtungen auf ungepuderte Latexhandschuhe mit niedrigem Proteingehalt. Eine Zusammenstellung von OP- und Untersuchungshandschuhen, welche Angaben über die von uns ermittelten Proteinkonzentrationen (modifizierte Lowry-Methode und Hochdruck-Flüssigkeits-Chromatographie, HPLC) enth?lt, soll ein Leitfaden bei der Auswahl allergologisch geeigneter Handschuhe sein. Eingegangen am 10. August 1996 Angenommen am 21. August 1996  相似文献   
23.
The sonographic morphology of urachal remnants is not well known and findings tend to be misinterpreted. We present urachal remnants in 16 asymptomatic children (1 week-16 years). In the prevesical part two different types of urachal remnants were found: the tubular type with a small outer muscle wall and the fusiform type with a muscle wall thickness up to 12 mm. Further subvariants are presented. Differential diagnosis of the fusiform type includes urachal cyst and tumorous muscle thickening.  相似文献   
24.
25.
A longitudinal study was performed in order to investigate virus excretion and viraemia during a clinical outbreak of the psittacine beak and feather disease in budgerigars (Melopsittacus undulatus). Viral nucleic acid was detected in feathers, cloacal swabs and blood samples. Overall, beak and feather disease virus (BFDV) DNA was detected most commonly in feather samples, followed by cloacal swabs, and least frequently from blood samples. In most cases the viraemia was short lived and correlated with clinical signs, such as feather abnormalities. Sequence analysis of the polymerase chain reaction fragment amplified from the replication-associated gene (ORF V1) indicated a close relationship with other BFDV isolates. Overall the highest level of nucleotide identity was found with the ORF V1 of another budgerigar isolate. Our results suggest that feather samples and cloacal swabs should be taken for polymerase chain reaction diagnosis to determine the presence of BFDV in an aviary, but that detection in these samples may not correlate well with psittacine beak and feather disease.  相似文献   
26.
This study reviewed the management and outcomes of 11 facial nerve neuromas treated in our institution during the past two decades with particular emphasis on surgical concepts and functional outcomes. All patients underwent complete surgical resection of their tumor. Eight patients (73%) were followed on an outpatient basis. A retrospective chart review for pre- and postoperative clinical and radiological data was performed. All facial neuromas were multi-segment tumors. All segments of the facial nerve were represented, but 54% involved the geniculate ganglion and 45% involved the labyrinthine or tympanic portions of the nerve, or both. Depending on the extent of sensorineural hearing loss, surgical removal was performed through the middle cranial fossa or translabyrinthine approach. To obtain adequate nerve reconstruction, we combined intra- and extracranial approaches (e.g., the transmastoidal and transtemporal routes). Regardless of the type of nerve reconstruction, the best recovery achieved was moderate facial weakness (House-Brackmann Grade III) in 75% of the patients, even in a patient who was Grade IV preoperatively. The choice of treatment for facial neuromas and surgical approach depends on the extent of tumor, grade of facial palsy, and hearing function. When facial palsy is present, complete resection is clearly indicated. In patients without facial dysfunction, a conservative strategy consisting of clinical and radiological observation should be considered as a treatment option.  相似文献   
27.
In orthodontic treatment employing arch guided tooth movement, rectangular wires are usually used to achieve three-dimensional controlled tooth movement. In the intention to optimize sliding mechanics and to improve the comfort of patients, edge beveled rectangular orthodontic wires are offered by different manufacturers. The objective of the study presented was to investigate the influence of differing but defined wire roundings on sliding mechanics of canine retraction. Employing the 0.018″ slot system, 0.016″×0.022″ standard steel wires (Remaloy and Remanium, Dentaurum Comp.) were tested. Force loss due to friction during canine retraction was determined using the Orthodontic Measurement and Simulation System (OMSS). In the arch guided distalization of canines, the average loss of force caused by friction was determined to be approximately 50%. Comparing wires with different edge bevel, the rounded wire in contrast to the wire with sharpest edge configuration results in a reduction of friction. Even a moderate wire rounding of the 0.016″×0.022″ steel wire results in about 10% reduction in frictional losses. However, dynamic analysis of tooth movement with the OMSS shows that there is no further improvement of sliding mechanics using wires with edge bevel exceeding the standard rounding of rectangular wires. In contrast, a strong edge bevel may result in a considerable loss of leveling.  相似文献   
28.
The present paper deals with a developing training element in cognitive behaviour therapy (CBT), the self‐practice of therapeutic techniques and the self‐exploration of the person of the therapist. Initially, the current status of this training element in CBT is discussed, and a short note on its terminology is presented. Then an overview of the most important objectives of self‐practice and self‐reflection in CBT, and the concepts and methods of practice of this element is given. The concepts focus on two major aims, the self‐exploration of the person of the therapist within and beyond his or her therapeutic practice, and the self‐application of therapeutic techniques (= self‐practice). In the second part of the paper empirical studies related to the outcome of self‐reflection and self‐practice on the development of the therapist and her or his therapeutic practice are reviewed. The few empirical studies show that trainees experience in their own view substantial professional and personal gains from this training tool, with the professional impact being more important than the personal one. The most important outcomes evaluated by subjective data from the trainees are improvements in self‐insight and self‐awareness and a better understanding of the therapist's role and the therapeutic change process. Additionally, a better understanding of CBT methods and of general therapeutic skills, such as empathy and role‐taking‐competencies, are reported by the trainees. The paper comes to the conclusion that self‐exploration and self‐practice are important components of CBT training. Consequences and recommendations for its integration into training courses for CBT are discussed as well as the necessity for more research in this area. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
29.
Distraction effects on muscle: Leg lengthening studied in rabbits   总被引:1,自引:0,他引:1  
We investigaed changes in the anterior tibial muscle during lengthening of the lower leg in rabbits. In 37 rabbits, an osteotomy of the right middle tibia was performed and was fixed by a unilateral external fixator. The rabbits were randomized into 6 groups. In groups 1, 2, and 3 the tibiae were distracted 0.5 mm/day. In groups 1 and 2, the rabbits were killed after 14 and 28 days of distraction, respectively, and in group 3 after 28 days of distraction, followed by 14 days of rest. Groups 1a, 2a, and 3a served as controls. They were treated similarly as groups 1, 2, and 3, but no distracton was performed. Proliferating cell nuclei were labeled with 5-bromo-2-deoxyuridine and were identified by immunohistochemical staining. The weight of the muscle was measured. During bone lengthening the muscle showed signs of growth, as indicated by increasing weight and number of proliferating cell nuclei. This was observed only during lengthening and it ceased when the lengthening was stopped.  相似文献   
30.
Ulrike Haun  Prof.  R. Rüchel  A. Spies 《Mycoses》1987,30(10):472-482
Summary: We describe a series of six serological tests for the diagnosis of deep-seated candidosis. The array comprises two commercial tests (antigen test, Ramco Inc., and antibody test, Roche), as well as four enzyme immunoassays which have been developed in this laboratory: an antigen test for detection of Candida-proteinase, the corresponding assays for monitoring of anti-proteinase antibodies, and two assays for monitoring of IgG and IgM against heterogenous metabolic antigens of C. albicans. The highly sensitive and specific proteinase antigen-test tolerates samples with high concentration of serum proteins. Proteinase antigen was detected in 10 out of 11 normal mice after intravenous infection with C. albicans blastospores. The proteinase antigen peaked between the second and fourth day after infection. A rise in corresponding antibodies was observed in all animals. No proteinase antigen was detected in sera of healthy human individuals; anti-proteinase antibody titers in these sera amounted up to 1:8000. In related ELISAs, using metabolic fungal antigens, titer values of specific IgG and IgM amounted to 5120 and 1280, respectively. The six tests were carried out in an comparative study under diagnostic conditions, the results of which are the subject of a forthcoming communication. Zusammenfassung: Ein Satz von sechs serologischen Tests für die Diagnostik der tiefen Candida-Mykosen wird vorgestellt. Die Gruppe schließt zwei kommerziell vertriebene Testbestecke ein (Latex-Agglutinationstest zum Antigennachweis, Ramco Inc., und Hämagglutinationstest zum Antikörpernachweis, Roche). Vier weitere Enzymimmuntests wurden von uns entwickelt: Ein Antigentest zum Nachweis von sekretorischer Candida-Protease, ein entsprechender Test zum Nachweis von Antikörpem gegen Candida-Protease, und zwei Assays zum Nachweis von IgG-bzw. IgM-Antikörpem gegen heterogene metabolische Antigene von C. albicans. Der empfindliche spezifische Protease-Antigentest toleriert hohe Konzentrationen unspezifischer Serumproteine und kann deshalb auf Serumproben in geringer Verdünnung (z. B. 1:20) angewandt werden. Protease-Antigen war in 200 fach verdünnten Seren von 10 aus 11 intravenös infizierten NWNI-Mäusen nachweisbar. Die höchste Antigen-Konzentration trat zwischen dem 2. und 4. Tag nach Infektion auf; die Serum-Halbwertszeit von gereinigter Protease in der Maus betrug etwa 60 nun. Ein Anstieg korrespondierender Antikörper war in alien infizierten Tieren zu beobachten. Auch im Serum gesunder Probanden waren Antiprotease-Antikörper bis zu einem Titer von 1:8000 nachweisbar; der Protease-Antigentest fiel hingegen immer negativ aus. Die Titer von Antikörpern gegen metabolische Candida-Antigene erreichten in derselben Gruppe von Seren Werte von 1:5120 bzw. 1:1280. Die sechs Tests wurden unter diagnostischen Bedingungen verglichen; Ergebnisse dieser Studie sind Gegenstand einer weiteren Mitteilung.  相似文献   
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