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91.
We evaluated the short-term results of percutaneous excimer laser angioplasty in acute myocardial infarction. Of the 18 patients studied, 2 were female and 16 male with a mean age of 56.6 +/- 12.1 years. Thrombolysis in myocardial infarction grades 0, 1, and 2 flow was observed in 10, 5, and 3 cases, respectively, prior to the procedure. The degree of stenosis was 97.9% +/- 5.1%. The lesion was crossed with a laser catheter in all cases, using a mean number of 808 +/- 384 laser pulses. Type C dissection developed in only 1 case (6%). Except for this case, distal flow was grade 3 in all the patients. Following the procedure, ST segment resolution exceeding 70% was achieved in 14 cases (78%) within the first 90 minutes. The success rate of laser ablation was 94% (17 patients). Stent implantation was performed in all the cases. In conclusion, laser angioplasty is an effective and reliable treatment for acute myocardial infarction.  相似文献   
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Purpose

The human mandible is subject to stimuli during its growth phase and also in adulthood. One of these stimuli may be absence of teeth, which gives rise to mandibular remodeling. Morphological changes may occur in different areas of this bone, such as in the gonial, condylar and ramus regions.

Objective

To investigate the influence of edentulousness on remodeling of the gonial angle of the mandible and the angle formed by the mandibular incisure.

Materials and method

Eighty-five dry mandibles from adults were examined: 42 from males and 43 from females. The mandibles were photographed using a camera coupled to a static support that was positioned 20 cm from the object to be photographed. The images were digitized and transferred to the Image J 1.42q software, in which the gonial angle of the mandible and the mandibular incisure angle were measured.

Results

There were no differences in the mandibular and mandibular incisure angles in relation to presence or absence of teeth, or between the right and left sides. The mandibular incisure angle was greater in the women.

Conclusion

Edentulousness did not cause remodeling of the gonial angle of the mandible or in the mandibular incisure angle.  相似文献   
95.
In the last decades, nine inherited errors of the distal part of cholesterol biosynthesis have been recognized. Affected patients present complex malformation syndromes involving different organs and systems with variable degrees of severity. We report on the phenotype evolution of three patients with enzymatic defects at three distinct steps of such pathway: Smith–Lemli–Opitz syndrome, X‐linked dominant chondrodysplasia punctata type 2 and congenital hemidysplasia with ichthyosiform erythroderma and limb defects syndrome. The patients' natural history, from childhood to adulthood, is thoroughly described in order to contribute for a better knowledge of these diseases. Our ultimate goals are to contribute for a better characterization of the long‐term course of these metabolic disorders and for the recognition of such diseases in older patients.  相似文献   
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We introduce a class of continuum shell structures, the Buckliball, which undergoes a structural transformation induced by buckling under pressure loading. The geometry of the Buckliball comprises a spherical shell patterned with a regular array of circular voids. In order for the pattern transformation to be induced by buckling, the possible number and arrangement of these voids are found to be restricted to five specific configurations. Below a critical internal pressure, the narrow ligaments between the voids buckle, leading to a cooperative buckling cascade of the skeleton of the ball. This ligament buckling leads to closure of the voids and a reduction of the total volume of the shell by up to 54%, while remaining spherical, thereby opening the possibility of encapsulation. We use a combination of precision desktop-scale experiments, finite element simulations, and scaling analyses to explore the underlying mechanics of these foldable structures, finding excellent qualitative and quantitative agreement. Given that this folding mechanism is induced by a mechanical instability, our Buckliball opens the possibility for reversible encapsulation, over a wide range of length scales.  相似文献   
98.
The fracture of anterior teeth in children and adolescents is a common injury. When most tooth structure is compromised and the broken fragment is not recovered, its restoration can become rather complex to both dentist and dental technician. Restoration of single anterior elements is one of the most demanding challenges in fixed prosthodontics. This article describes a clinical case of a 13-year-old patient with an extensive fractured central incisor and contra lateral incisor. Endodontic treatment was performed on both teeth, and a temporary removable appliance was made for esthetics. One month later, an indirect esthetic post and core was made for each tooth, and provisionals were placed. After a 6-month period of soft tissue stabilization, two pressed all-ceramic crowns were fabricated and bonded to the preparations. The authors believe this to be a stable long-term option relative to the reminiscent tooth structure, esthetic demand, and occlusal features of the case.  相似文献   
99.
Abstract – Objectives: To compare the fracture resistance of bovine teeth after intracoronal bleaching with sodium percarbonate (SPC) or sodium perborate (SP) mixed with water or 20% hydrogen peroxide (HP). Materials and methods: Fifty extracted bovine teeth were divided into four experimental groups (G1–G4) and one control (n = 10) after endodontic treatment. Following root canal obturation, a glass ionomer barrier was placed at the cemento–enamel junction. After that, the pulp chambers were filled with: G1 – SP with water; G2 – SP with 20% HP; G3 – SPC with water; and G4 – SPC with 20% HP. No bleaching agent was used in the control group. Coronal access cavities were sealed with glass ionomer and specimens were immersed in artificial saliva. The bleaching agents were replaced after 7 days, and teeth were kept in artificial saliva for an additional 7 days, after which the pastes were removed and the coronal access cavities were restored with glass ionomer. Crowns were subjected to compressive load at a cross head speed of 0.5 mm min?1 applied at 135° to the long axis of the root by an EMIC DL2000 testing machine, until coronal fracture. Data were statistically analysed by anova and Tukey test. Results: No differences in fracture resistance were observed between the experimental groups (P > 0.05). However, all experimental groups presented lower fracture resistance than the control group (P < 0.05). Conclusion: SPC and SP led to equal reduction on fracture resistance of dental crowns, regardless of being mixed with water or 20% HP.  相似文献   
100.
Intrauterine ischemia of the limbs is a rare condition involving thrombosis and ischemia of the extremities before birth. The clinical presentation depends on the extremity affected as well as the timing of thrombosis. Very few cases with extremity hypoperfusion and gangrene due to intrauterine thrombosis have been reported in the literature, and therefore there is no consensus on the optimal therapeutic strategy for such cases. Presented here is a case of a newborn with intrauterine brachial arterial thrombosis of the right upper extremity who was successfully treated by a combination of recombinant tissue plasminogen activator, enoxaparin and collagenase application followed by surgery.  相似文献   
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