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Mittlmeier  T.  Arndt  D.  Beck  M.  Gradl  G. 《Trauma und Berufskrankheit》2007,9(1):S61-S68
In a prospective outcome study, 76 of 116 patients were examined 1 year after reduction and internal fixation of a dislocated humeral head fracture with an antegrade straight intramedullary nailing system using angular and sliding stable interlocking screws. Of these patients, 77% had three- or four-segment fractures according to the Neer classification. The mean absolute Constant-Murley score 1 year after trauma was 70.0±19.7 points. During the observation period, 51 complications occurred in 44 of 76 patients; of these 44 patients, only 27 required therapeutic interventions. The highest frequency of complications was apparent in those with Neer IV fractures (73.7%), while those with Neer III and Neer IV/III fractures had complication rates of 50% and 52.5%, respectively. Patients without complications showed good or excellent functional results, ranging from 78% to 96% (relative Constant-Murley score of the contralateral noninjured side). In patients with complications, the relative Constant-Murley score ranged from 51% to 65%. Despite the high complication rate, the antegrade angular and sliding stable interlocking nail can be considered effective for treating dislocated humeral head fractures. Modifications of the surgical technique for stabilizing the tubercles (additional suture cerclage fixation of fragmented tubercles) and a polyetheretherketone (PEEK) insert in the proximal segment of the nail to prevent the fixation screws from backing out can substantially decrease some of the most frequent complications.  相似文献   
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ABSTRACT. The phonological abilities of two groups of 4–9-year-old intellectually impaired Cantonese-speaking children are described. Children with Down's syndrome did not differ from matched non-Down's syndrome controls in terms of a lexical comprehension measure, the size of their phoneme repertoires, the range of sounds affected by articulatory imprecision, or the number of consonants, vowels or tones produced in error. However, the types of errors made by the Down's syndrome children were different from those made by the control subjects. Cantonese-speaking children with Downs syndrome, as compared with controls, made a greater number of inconsistent errors, were more likely to produce non-developmental errors and were better in imitation than in spontaneous production. Despite extensive differences between the phonological structures of Cantonese and English, children with Downs syndrome acquiring these languages show the same characteristic pattern of speech errors. One unexpected finding was that the control group of non-Down's syndrome children failed to present with delayed phonological development typically reported for their English-speaking counterparts. The argument made is that cross-linguistic studies of intellectually impaired children's language acquisition provide evidence concerning language-specific characteristics of impairment, as opposed to those characteristics that, remaining constant across languages, are an integral part of the disorder. The results reported here support the hypothesis that the speech disorder typically associated with Down's syndrome arises from impaired phonological planning, i.e. a cognitive linguistic deficit.  相似文献   
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Novel diagnostic methods (immunoblotting, immunofluorescence test) have been proved to be very sensitive and specific for detecting enteropathogenic bacilli. 28 patients with chronic enterocolitis were investigated. In 50% (14/28) of these patients Yersinia enterocolitica could be visualized in biopsies by immunofluorescence. The serum of 8 patients also contained IgA-antibodies against plasmid encoded released proteins of Y. enterocolitica. This paper reports evidence for persistence of Yersinia bacilli in a group of patients with chronic enterocolitis. Further studies must show, if these results may have therapeutic implications.  相似文献   
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The suitability of a pulsed dye laser (504 nm) in experimental and clinical angioplasty was investigated. In an experimental study, the ablation thresholds were 3 J/cm2 +/- 8 (mean +/- standard deviation) for fibrofatty plaque and 25 J/cm2 for calcified tissues under saline. At a radiant exposure of 10 J/cm2 the etch rates were 1.7 microns per pulse +/- 0.3 for media, 2.8 microns/pulse +/- 0.4 for normal intima, and 3.9 microns/pulse +/- 1.1 for fibrofatty plaque (P less than .05). Pressure wave effects with a separation of tissue layers were predominantly localized at the internal elastic lamina. Thermal injury with vacuolations extended 15 microns +/- 6 into adjacent tissue. For clinical study, laser-assisted balloon angioplasty was performed in 10 patients (64 years +/- 14) with occlusions of peripheral arteries using a 9-F multifiber ring catheter. Lesion length ranged from 2 to 12 cm (mean, 7 cm). Laser angioplasty with an 80 mJ/pulse decreased the mean stenosis from 100% to 58% +/- 12% (P less than .005). The ankle-brachial index rose from a median of 0.48 to 0.88 (P less than .001). In 33% of patients, there were subintimal dissections after laser angioplasty. After a mean follow-up of 10.2 months, the overall clinical success was 70% with a primary patency of 78%. The over-the-wire approach with a pulsed dye laser may constitute a safe and feasible tool in laser angioplasty.  相似文献   
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Patients' pre- and postoperative self-reports were compared with reports of non-medical observers to investigate whether improved self-esteem is a direct result of increased social acceptance in maxillo- and craniofacial patients. Twenty-two children and adolescents undergoing reconstructive surgery for a variety of facial deformities were asked to rate their physical appearance on the Hay's Scale and fill out the Piers-Harris Self-Concept Scale. Their ratings were compared with scores given by a panel of lay volunteers on random presentation of pre- and postoperative photographs of the same patients. Patients rated their appearance as noticeably improved after surgery, their self-esteem rose significantly and they reported more social adeptness and acceptance at home and school. Raters observed only relatively subtle changes. Apparently, quality of life improved for the postsurgical facial patient because of increased self-esteem and confidence, which free him to overcome social barriers.  相似文献   
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BACKGROUND: In a previous investigation we reported on magnetic forces in the static magnetic field of a 1.5 Tesla MRI system. The aim of the present investigation was to assess forces on orthodontic wires in a high field strength MRI system at 3 Tesla. MATERIALS AND METHODS: Thirty-two different orthodontic wires (21 archwires, eight ligature wires and three retainer wires) were investigated in a 3 Tesla high field strength MRI system (Intera, Philips Medical Systems, Best, The Netherlands). Translational forces were measured by the deflection angle test (ASTM F2052-02), and rotational forces assessed on a 5-point qualitative scale. RESULTS AND CONCLUSION: Translational forces ranged between 43.5 mN and 136.1 mN for retainer wires and between 0.6 mN (Noninium) and 208.4 mN (Orthos Stainless Steel) for steel archwires. Translational forces were up to 53.8 times as high as gravitational forces for retainer wires and up to 54.5 times as high for steel archwires, associated with marked rotational forces for the most part. Archwires manufactured from nickel-titanium, titanium-molybdenum and cobalt-chromium and different ligature wires showed no or negligible forces in the magnetic field. Carefully ligated wires should not present a risk due to translational and rotational forces in the high field MRI system at 3 Tesla.  相似文献   
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