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141.
Periacetabular osteotomy (PAO) is a surgical procedure to correct acetabular orientation in developmental dysplasia of the hip (DDH). It changes the position of the acetabulum to increase femoral head coverage and distribute the contact pressure over the cartilage surface. The success of PAO depends significantly on the surgeon's experience. Using computed tomography data from patients with DDH, we developed a 3D finite element (FE) model to investigate the optimal position of the acetabulum following PAO. A virtual PAO was performed with the acetabulum rotated in increments from the original center edge (CE) angle. Contact area, contact pressure, and Von Mises stress in the femoral and pelvic cartilage were analyzed. Five dysplastic hips from four patients were modeled. Contact area, contact pressure, and Von Mises stress in the cartilage all varied according to the change of CE angle through virtual PAO. An optimal position could be achieved for the acetabulum that maximizes the contact area while minimizing the contact pressure and von Mises stress in the pelvic and femoral cartilage. The optimal position of the acetabulum was patient dependent and did not always correspond to what would be considered a “normal” CE angle. We demonstrated for the first time the interrelation of correction angle, contact area, and contact pressure between the pelvic and femoral cartilage in PAO surgery. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 472–479, 2013  相似文献   
142.
OBJECTIVES: (1) To show that total thyroidectomy (TT) can be performed in multinodular goiter (MG) by surgeons with experience in endocrine surgery with a definitive complication rate of 1% or less; and (2) to analyze the risk factors for complications in these patients. SUMMARY BACKGROUND DATA: There is current controversy over the role of TT in the treatment of MG; although there are potential benefits, high rates of complications are not acceptable in surgery for a benign pathology. PATIENTS AND METHOD: A prospective study was conducted on 301 MGs meeting the following criteria: (1) bilateral MG; (2) no prior cervical surgery; (3) operation by surgeons with experience in endocrine surgery; (4) no associated parathyroid pathology; (5) no initial thoracic approach; and (6) minimum follow-up of 1 year. Age, sex, time of evolution, symptoms, cervical goiter grade, intrathoracic component, thyroid weight, and presence of associated carcinoma were analyzed as risk factors for complications. The chi test and a logistic regression analysis were applied. RESULTS: Complications were presented by 62 patients (21%), corresponding to 29 hypoparathyroidisms, 26 recurrent laryngeal nerve injuries, 4 lesions of the superior laryngeal nerve, 3 cervical hematomas, and 1 infection of the cervicotomy. The variables associated with the presence of these complications were hyperthyroidism (P = 0.0033), compressive symptoms (P = 0.0455), intrathoracic component (P = 0.0366), goiter grade (P = 0.0195), and weight of excised specimen (P = 0.0302); hyperthyroidism (relative risk [RR] 2.5) and intrathoracic component (RR 1.5) persisted as independent risk factors. Definitive complications appeared in 3 patients (1%), corresponding to 2 hypoparathyroidisms and 1 recurrent laryngeal nerve injury. Two cases corresponded to a toxic goiter, and the third to an intrathoracic goiter with compressive symptoms. CONCLUSION: In endocrine surgery units, TT can be performed for MG with a definitive complication rate of around 1%; the main independent risk factors for the development of complications are hyperthyroidism and goiter size.  相似文献   
143.
Eleven patients with connective tissue diseases were found to have bronchiolar lesions associated with minimal or no alveolar septal thickening. Seven of these patients had rheumatoid arthritis, 3 had Sjögren’s syndrome, and 1 had ankylosing spondylitis. Radiographic studies showed an interstitial pattern in all patients. The patients were nonsmokers and received no treatment prior to biopsy. All lung biopsy specimens showed inflammatory bronchiolar lesions which consisted of bronchiolar and peribronchiolar lymphocytic infiltrates (follicular bronchiolitis). The bronchiolar lesion has been reported previously in patients with connective tissue diseases treated with D-penicillamine; whether it represents a component of the systemic disease or a lack of effect of the therapeutic agent had not been established. The present study shows that several connective tissue diseases can be associated with inflammatory bronchiolar lesions.  相似文献   
144.
Carcinoid heart disease secondary to ovarian carcinoid is arare finding, with only 12 cases reported in the literatureto date(1–3). Most ovarian carcinoids arise from ovariancysts or teratomata, the ‘pure’ carcinoid beingexceedingly rare(4). We present a case of carcinoid syndromewith tricuspid valve involvement in a patient with ‘pure’ovarian carcinoid.  相似文献   
145.
Early second language (EL2) learners generally perform more poorly than monolinguals in specific language domains, presenting similarities with children affected by specific language impairment (SLI). As a consequence, it can be difficult to correctly diagnose this disorder in EL2 children. The current study investigated the performance of 120 EL2 and 40 age-matched monolingual children in object clitic production and nonword repetition, which are two sensitive clinical markers of SLI in Italian. Results show that EL2 children underperform in comparison to monolinguals in the clitic task. However, in contrast to what is reported on Italian-speaking children with SLI, EL2 children tend not to omit clitics but instead produce the incorrect form, committing agreement errors. No differences are found between EL2 and monolingual children on nonword repetition. These results suggest that, at least in Italian, EL2 children only superficially resemble children with SLI and, on closer inspection, present a qualitatively and quantitatively different linguistic profile.  相似文献   
146.
International Journal of Legal Medicine - The recently developed probabilistic genotyping software package MaSTR™ (SoftGenetics LLC) was used to develop statistical weight estimates for a...  相似文献   
147.
148.
Peripheral blood lymphocyte (PBL) count may reflect the immune status of cancer patients. We retrospectively analyzed the predictive and prognostic impact of baseline and post-chemotherapy PBL counts in a homogeneous group of 103 breast cancer patients treated with neoadjuvant chemotherapy (anthracyclines and taxanes). In univariate analysis, baseline PBL under 1500 × 10(6)/L (p = 0.013; hazard ratio [HR]: 2.80, 95%CI 1.24-6.61), and PBL decrease >200 × 10(6)/L after the first cycle of chemotherapy (p = 0.047; HR: 2.82, 95%CI 1.01-7.86) were significantly related to disease free survival. In multivariate analysis, both baseline PBL count less than 1500 × 10(6)/L (p = 0.034; HR: 3.32, 95%CI 1.09-10.02) and PBL decrease >200 × 10(6)/L after first cycle (p = 0.032; HR: 3.25, 95%CI 1.10-9.56) showed independent prognostic value for worse disease free survival. No effect was observed for overall survival. Our data support the relevance of pre- and post-chemotherapy PBL for breast cancer recurrence after neoadjuvant chemotherapy.  相似文献   
149.
The noninvasive methods of cognitive neuroscience offer new possibilities to study language. We used neuronavigated multisite transcranial magnetic stimulation (TMS) to determine the functional relevance of 1) the posterior part of left superior temporal gyrus (Wernicke's area), 2) a midportion of Broca's area (slightly posterior/superior to apex of vertical ascending ramus), and 3) the midsection of the left middle temporal gyrus (MTG), during overt picture naming. Our chronometric TMS design enabled us to chart the time points at which neural activity in each of these regions functionally contributes to overt speech production. Our findings demonstrate that the midsection of left MTG becomes functionally relevant at 225 ms after picture onset, followed by Broca's area at 300 ms and Wernicke's area at 400 ms. Interestingly, during this late time window, the left MTG shows a second peak of functional relevance. Each area thus contributed during the speech production process at different stages, suggesting distinct underlying functional roles within this complex multicomponential skill. These findings are discussed and framed in the context of psycholinguistic models of speech production according to which successful speaking relies on intact, spatiotemporally specific feed forward and recurrent feedback loops within a left-hemispheric fronto-temporal brain connectivity network.  相似文献   
150.
Background: In recent years, numerous scientific publications have endorsed the superiority of the ProSeal? laryngeal mask airway (PLMA) over the Classic? laryngeal mask airway (cLMA) in adults, children, and infants. The PLMA forms a better seal for both the respiratory and gastrointestinal tracts, provides easier access to the gastrointestinal tract, and exerts lower mucosal pressures for a given seal pressure. This study aims to determine whether this superiority can also be observed for the size 1 PLMA used in anesthetized neonates and infants with positive pressure ventilation. Methods: Sixty consecutive neonates and infants undergoing elective surgical procedures were randomized to airway management with the size 1 PLMA or cLMA. For all patients, we recorded ease of insertion, effective airway time, number of placement attempts, oropharyngeal leak pressure, fiberoptic position, audible leaks, mask displacement, number of reinsertions during maintenance, gastric insufflation, and frequency of blood stain. Results: Ease of insertion, successful insertion in <3 attempts, fiberoptic position of the airway tube, and frequency of blood stain were similar in both groups. Effective airway time was lower for the PLMA group (30.5 vs 35.6 s). Oropharyngeal leak pressure was higher with the PLMA (32.9 vs 22.2 cm H2O, P < 0.001) and gastric insufflation less common (0% vs 6%, P = 0.492). There were fewer mask displacements during maintenance of anesthesia with the PLMA (0% vs 26.7%, P < 0.001). Mask reinsertion was not necessary during maintenance of anesthesia with the PLMA, although it was necessary in 14 cases in the cLMA group (0% vs 46%, P < 0.001). Audible leaks were less common with the PLMA (0% vs 46%, P < 0.001). Conclusions: We conclude that the size 1 PLMA is a stable, safe, and efficacious airway control device during neonatal and infant anesthesia, allowing higher peak airway pressure during positive pressure ventilation, with fewer mask displacements and gastric insufflations than the cLMA.  相似文献   
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