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This study evaluated the effect of new motions of the motor TriAuto ZX2 on the cyclic fatigue of endodontic instruments. Vortex Blue 35.06 instruments were divided into four groups (n = 10) and tested for fatigue in a curved artificial canal (90° and 2 mm radius) using the following motions: continuous rotation (CR), Optimum Torque Reverse (OTR) set at 180° and the Optimum Glide Path (OGP), which was tested at 90° and 240°. The time to fracture (TTF) and the lengths of the fractured fragments were recorded. The mean TTF was significantly different among the groups (anova , P < 0.05): OGP 90° (213.39 ± 27.45), OTR 180° (121.24 ± 17.03), OGP 240° (45.24 ± 5.61) and CR (8.43 ± 1.27). Weibull analysis confirmed the shortest life expectancy for CR and the longest survival for OGP at 90°. The resistance to fatigue was affected by motions and pre‐set angles. The proprietary movements that are currently available for endodontic instruments were classified according to their kinematics.  相似文献   
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The purpose of the study was to compare an interview measure of quality of object relations to questionnaire and interview measures of recent interpersonal functioning with respect to the prediction of therapeutic alliance and psychotherapy outcome. The sample consisted of 64 patients who had received approximately 20 sessions of short-term individual psychotherapy within a controlled, clinical-trial investigation. Ratings of therapeutic alliance were provided independently by the patient and the therapist after each session. Outcome measures, which were provided by three sources (patient, therapist, and independent assessor), covered the areas of interpersonal functioning, psychiatric symptomatology, self-esteem, and life satisfaction. Quality of object relations, which characterizes the patient's lifelong pattern of relationships, was the best predictor. It was significantly related to patient-rated and therapist-rated therapeutic alliance and to patient improvement of both general symptomatology and specific target problems. The study also replicated previous studies that have reported significant relationships between therapeutic alliance and therapy outcome. The advantages of pretherapy predictors of therapy outcome, such as quality of object relations, are discussed.  相似文献   
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Over the past 10 years, arteriography has become a well-established technique for the diagnosis of acute lower gastrointestinal bleeding, but not particularly for rectal bleeding. However, to the authors' knowledge, the technique of middle hemorrhoidal artery embolization has rarely been reported in the literature. In the present report, three patients with life-threatening rectal bleeding are presented, which was controlled by superselective embolization of the middle hemorrhoidal artery or selective embolization of the internal iliac artery as a last resort.  相似文献   
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Abstract – Traumatic dental injuries often occur to the teeth and their supporting tissues and they are the main reasons for emergency visit to a dental clinic. Management of a fracture depends on its position and the extent of root involvement. Horizontal root fractures are not seen frequently and the treatment consists of reduction and long‐term rigid fixation of the coronal segment. The present case demonstrates the successful management of two horizontally fractured maxillary central incisors with a follow‐up period of 9 months.  相似文献   
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Autotransplantation of splenic tissue   总被引:4,自引:0,他引:4  
Autotransplantation of splenic fragments has already been carried out in humans. The optimal size of the particles and amount of tissue required for this procedure has yet to be found. In normal young pigs and miniature piglets, autologous splenic tissue was transplanted into the greater omentum. The regenerated splenic mass, splenic blood flow, and histology were studied six months later. Implanting small splenic particles produced comparable results to implanting thin slices of splenic tissue. The mass of regenerated splenic tissue was only 3.1 g after implanting the whole spleen and 4.5 g after transplanting half of the spleen, which means 5.3% and 7.8% respectively of the weight of control spleens. The blood flow per gram in the regenerated splenic tissue was much lower than in the normal spleen. The blood flow in the whole of the splenic tissue is important for the clearance function of the spleen. Six months after transplanting the whole or half of the spleen, the blood flow to the regenerated splenic tissue was only 1% of that in the control minipigs. When half of the spleen was left in situ, as a model for a partial splenectomy, and the other half transplanted, the regenerated mass was only 3.4% of all splenic tissue and the blood flow 1.5% of the total splenic blood flow. In this model the regenerated splenic mass was independent of the size of the implants and the mass of implanted tissue. The extremely low blood flow indicates an inadequate clearance function and thus the protective function would probably be negligible.  相似文献   
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AIMS AND OBJECTIVES: To screen for, and to treat, depression in COPD patients in a general practice surgery, and to test the feasibility of the screening method. METHODS: We sent The Beck Depression Inventory (BDI) Short-Form Questionnaire to all patients on the COPD register (n=69) by post, excluding those already diagnosed with depression (n=3). We sent appointments to all responders with moderate to severe depression and offered them treatment including antidepressants and pulmonary rehabilitation if the diagnosis was confirmed. RESULTS: Of the 66 patients to whom we sent questionnaires, 43 were returned completed and 13 of these had significant depression (30%). 10 of these patients were contactable and attended for review. The diagnosis of depression was confirmed in all 10 cases. Treatment options were discussed; five chose antidepressant medication, three chose pulmonary rehabilitation and two declined treatment. CONCLUSION: We identified and treated a significant number of depressed COPD patients in a general practice setting using this screening method. This method could have wider applications for screening, although further trials are needed.  相似文献   
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