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991.
Objective:To investigate risk factors specific to posterior crossbite and anterior open bite at the age of 3 years.Materials and Methods:The study included 422 children of the French EDEN mother-child cohort. The main outcomes were the presence of posterior crossbite and anterior open bite assessed by dentists at 3 years. Social characteristics (collected during pregnancy), neonatal characteristics (collected at birth), duration of breast-feeding (collected prospectively), sucking habits at 3 years, and open lips (as a proxy for mouth breathing) were studied and two logistic regressions conducted.Results: Preterm birth appears to be a risk factor specific for posterior crossbite (OR: 3.13; 95% CI: 1.13–8.68), whereas small for gestational age seems to be associated with a lower risk of posterior crossbite (OR: 0.32; 95% CI: 0.12–0.87). Ongoing pacifier or thumb sucking at 3 years is a risk factor for both posterior crossbite and anterior open bite.Conclusions: Children born preterm seem to be more at risk for posterior crossbite than those born at term. Different mechanisms may be involved in posterior crossbite and anterior open bite.  相似文献   
992.
Drug-eluting stents have been investigated as a treatment option for in-stent restenosis after bare metal stenting. However, it remains unclear whether overlapping drug-eluting stents have a toxic effect on the vessel wall. The aim of this study was to analyze the 1-year intravascular ultrasound findings after 2 overlapping sirolimus-eluting stent implantations in patients with in-stent restenosis lesions. Eight patients required 2 sirolimus-eluting stents, 18 mm in length, for full lesion coverage; these stents were implanted with >1-mm overlap. At 1-year follow-up, there were no significant quantitative changes in intravascular ultrasound measurements within the overlapped segment.  相似文献   
993.
The combination of cryo-microscopy and electron tomographic reconstruction has allowed us to determine the structure of one of the more complex viruses, intracellular mature vaccinia virus, at a resolution of 4-6 nm. The tomographic reconstruction allows us to dissect the different structural components of the viral particle, avoiding projection artifacts derived from previous microscopic observations. A surface-rendering representation revealed brick-shaped viral particles with slightly rounded edges and dimensions of approximately 360 x 270 x 250 nm. The outer layer was consistent with a lipid membrane (5-6 nm thick), below which usually two lateral bodies were found, built up by a heterogeneous material without apparent ordering or repetitive features. The internal core presented an inner cavity with electron dense coils of presumptive DNA-protein complexes, together with areas of very low density. The core was surrounded by two layers comprising an overall thickness of approximately 18-19 nm; the inner layer was consistent with a lipid membrane. The outer layer was discontinuous, formed by a periodic palisade built by the side interaction of T-shaped protein spikes that were anchored in the lower membrane and were arranged into small hexagonal crystallites. It was possible to detect a few pore-like structures that communicated the inner side of the core with the region outside the layer built by the T-shaped spike palisade.  相似文献   
994.
Middle Paleolithic fossil human remains from the Sima de las Palomas in southeastern Iberia (dated to ≤43,000–40,000 calendar years before present) present a suite of derived Neandertal and/or retained ancestral morphological features in the mandibular symphysis, mandibular ramus, dental occlusal morphology, and distal hand phalanx. These traits are combined with variation in the mandibular corpus, discrete dental morphology, tooth root lengths, and anterior dental size that indicate a frequency difference with earlier Iberian and more northern European Neandertals. The Palomas Neandertals therefore confirm the late presence of Neandertals associated with the Iberian persistence of the Middle Paleolithic, but suggest microevolutionary processes and/or population contact with contemporaneous modern humans to the north.  相似文献   
995.
AIMS: Left ventricular (LV) pacing via transvenous implantation has an overall success rate ranging from 88% to 92%. The aim of this study was to assess whether LV pacing via limited thoracotomy would be feasible and safe when used on a routine basis for those cases in which standard transvenous procedures proved to be ineffective or unsatisfactory. METHODS AND RESULTS: We enrolled 33 patients (8 females, 65+/-10 years) who experienced a transvenous implantation failure. All patients underwent a limited thoracotomy and an epicardial lead was implanted. The procedure time was 51+/-28 min. No surgical or post-operative complications occurred and optimal lateral position was achieved for all patients. In the 12 months follow-up period, 5 patients died from refractory heart failure, the remaining patients did not experience complications. At implant, the mean pacing threshold was 1.3+/-0.7 V, bi-ventricular pacing impedance was 476+/-201 Omega and R-wave amplitude was 15.0+/-6.1 mV. No significant differences were found in any of the electrical parameters between baseline and follow-up. Significant improvement was observed in functional and echocardiographic parameters. CONCLUSION: Our results suggest that a combined approach to cardiac resynchronisation therapy delivery, including a transvenous attempt followed by a back up thoracotomic procedure, could potentially guarantee the success.  相似文献   
996.

Introduction

Orthognathic surgery is widely used to correct dentofacial discrepancies. However, this procedure presents numerous possible complications. The aim of our study is to review intraoperative and postoperative complications related to orthognathic surgery based upon a 10-year period in the Maxillofacial Surgery Department of Federico II University of Naples.

Materials and methods

Medical records of 423 patients who undergone orthognathic surgery in a 10-year period were retrospectively analyzed and complications was noted. Statistical analysis was conduced in order to understand if the type of surgical procedure influenced complications rate.

Results

One hundred eighty-five complications in 143 (33.8%) of the 423 treated patients were reported. Complications detected were nerve injury (49 cases, 11.9%), infections (10 cases, 2.4%), complications related to fixation plates or screws (30 cases, 7.1%), bad split osteotomy (8 cases, 1.9%), secondary temporo-mandibular joint disorders (36 cases, 8.5%), dental injuries (21 cases, 5%), condilar resorption (2 cases, 0.5%), and necessity of a second-time surgery (24 cases, 5.7%).

Conclusions

Serious complications seem to be quite rare in orthognathic surgery. Some of the surgical complications found are related to the surgeon experience and not strictly to the risks of the operation itself. Understanding potential complications allows the surgeon to guarantee safe care through early intervention and correctly inform the patient in the preoperative colloquy.
  相似文献   
997.
  • Stent with reduced axial force have an increased risk of longitudinal stent deformation (LSD).
  • Deep guidewire catheter intubation after ostial stent deployment or attempting to push a device through an already deployed stent are frequently encountered in patients with LSD.
  • Optimization of longitudinal strength along with increasing knowledge of LSD will likely reduce the frequency of this complication.
  相似文献   
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