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AIM: The aim of this retrospective clinical study was to evaluate dental arch, skeletal, dentoalveolar, and soft tissue profile changes following treatment of Class III malocclusion by means of the Function Regulator (FR-3) appliance. SUBJECTS AND METHODS: The study sample consisted of 14 growing patients (seven boys and seven girls) with a mean age of 9.7 +/- 1.1 years presenting Class III malocclusion. They were treated with an FR-3 appliance exclusively for a period of 2.4 +/- 0.6 years. Dental casts and lateral cephalometric radiographs were obtained immediately before initiation and after completion of treatment with the FR-3 appliance. Thirteen variables were used for the dental cast analysis and 61 variables for the cephalometric analysis. The paired t-test was utilized to evaluate the presence of significant changes (p < 0.05). RESULTS: The evaluation of the dental casts revealed that there was a significant increase in intermolar, interpremolar, and intercanine width of the maxilla and of palatal height after treatment. Concerning the mandible, an increase in intermolar and intercanine width and a decrease in lower arch depth were observed. Cephalometric evaluation revealed a significant decrease in SNB angle and an increase in ANB angle, overjet, facial convexity, nose prominence, and lower soft tissue face height. There was an increase in upper lip thickness and a decrease in lower lip convexity observed after treatment. CONCLUSIONS: The results of this study confirm a favorable functional and esthetic maxillary and mandibular position following treatment by means of the function regulator (FR-3) appliance.  相似文献   
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Purpose: It was investigated whether alterations in neuronal structure and function occasioned by strabismic amblyopia also may be reflected in alterations in the expression on Y type neurons of a Cat-301 antibody sensitive antigen in the lateral geniculate nucleus (LGN) and cortex of our cat model of strabismic amblyopia. Methods/Results: The percentage of positively labelled cells was reduced in LGN laminae that received input from the deviated eye in strabismic amblyopic cats compared with normal cats. In the strabismic cortex, the density of immunopositive neurons was significantly reduced compared with normal, the effect being most pronounced in layer IV Conclusions: Despite previous physiological recordings indicating a decrease in X-cell associated acuity in strabismic amblyopia, the present findings imply that the changes in the early visual experience occasioned by strabismus also produce specific molecular changes in theY neuronal class.  相似文献   
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BACKGROUND CONTEXT: Computerized frameless stereotactic image-guidance has been used in recent years to improve the accuracy and safety of pedicle screw placement during spine surgery. Because the possibility of intervertebral motion exists, and because the patient is usually in a different position when preoperative imaging is performed compared with the operative position, it has been suggested that the imaging model of the complete lumbar spine and the surgically exposed lumbar spine may be significantly discordant. Consequently, current protocols suggest registering each spinal level (single-level registration) separately before pedicle screw placement at that level, a time-consuming process. PURPOSE: To assess the accuracy of single-time multilevel registration for multilevel pedicle screw placement during image-guided, computer-assisted spine surgery, in the setting of degenerative disorders of the lumbar spine. STUDY DESIGN/SETTING: This is a prospective clinical and radiological study of 45 patients with degenerative disorders of the lumbar spine who underwent instrumented fusion with the use of single-time multilevel registration computer-assisted, image-guided tomography. The accuracy of the pedicle screws placement was confirmed on the basis of a protocol that included intraoperative spontaneous electromyographic (EMG) recordings, direct pedicle visualization, and computer tomography (CT) scans when clinically indicated during the follow-up period. PATIENT SAMPLE: Forty-five consecutive patients who fulfilled the criteria of computer-assisted, image-guided tomography pedicle screw placement for degenerative lumbar spine disease without overt instability. OUTCOME MEASURES: The principal outcome measure was the accuracy of pedicle screw placement with single-time multilevel registration for multilevel pedicle screw placement during image-guided, computer-assisted spine surgery; postoperative CT performed for clinical indications during the follow-up course was used for the assessment of pedicle screw placement. METHODS: Patients were assessed clinically before and after the operation. Data from 45 consecutive cases of image-guided, computer-assisted lumbar spinal fusion were statistically analyzed to determine the relationship between the number of levels registered during single-time registry and the mean registration error (MRE). Intraoperative spontaneous EMG, direct visualization, and postoperative CT scans were used to assess the accuracy of pedicle screw insertion. RESULTS: None of the patients involved in this study experienced clinical sequelae of improper pedicle screw placement. MREs after surface mapping and after point merge were small (less than 1.00 mm and less than 3.00 mm, respectively). During the intraoperative assessment of the pedicle screws placement, no significant spontaneous EMG activity was recorded and the pedicular walls were found intact in direct visualization. The postoperative CT scans showed in 10 patients accurate placement in 55 of the 57 pedicle screws with expansion of the medial wall in two screws. CONCLUSIONS: Single-time, multilevel registration may decrease operative time relative to repeated, single-level registrations, without compromising the increased accuracy of pedicle screw placement afforded by this technique in the setting of degenerative disorders of the lumbar spine. Despite the advantages in computer-guided image surgery, cautious application in the individual patient is recommended until more comprehensive data can be gathered in specific degenerative pathology with overt instability; thus the knowledge of the anatomy remains crucial.  相似文献   
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Antegrade interlocking nailing of humeral shaft fractures   总被引:5,自引:0,他引:5  
The results of 39 humeral shaft fractures (37 patients) treated with antegrade locked nailing using a Russell–Taylor nail were reviewed. There were 30 acute fractures, 6 fractures malaligned in a hanging cast or brace, and 3 pathological fractures. Patient age ranged from 26 to 80 years (average, 59.7 years) and average follow-up was 25.7 months (range, 6–48 months). Fracture union was achieved in 92.3% of our cases, while shoulder function was excellent or good in 87.2% of cases. Antegrade locked nailing offers a dependable solution for the treatment of humeral shaft fractures, especially in polytrauma patients and cases of segmental or pathological fractures. Far less satisfactory results were obtained in comminuted fractures of the proximal third in the humerus, especially in osteoporotic patients, and we therefore advocate caution with the use of intramedullary nailing in this type of fracture. Certain technical aspects such as avoiding nailing the fracture in distraction, properly countersinking the tip of the nail, and achieving adequate fixation stability have been found to be of paramount importance to reduce the incidence of delayed union/non-union rate and to obtain better functional results from the shoulder joint.  相似文献   
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This paper describes the administrative organisation of veterinary public health (VPH) activities in seven countries of the Western Mediterranean region. These structures vary greatly, as a function of the national administrations overall and, in particular, as a result of assigning VPH to either the Ministry of Agriculture or Public Health. Whereas the VPH unit is generally involved in specific veterinary food hygiene activities, the control of zoonotic diseases is most often assigned to the Veterinary Services. In most countries of the region, VPH is still approached as too narrow a discipline, and the importance of VPH activities is often not recognised by decision-makers at the highest governmental levels.  相似文献   
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