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Pediatric Surgery International - The programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) pathway has garnered much attention for its roles in clinical oncology. The aim of this study was...  相似文献   
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Our aim was to evaluate the long-term skeletal stability of the mandible in 21 patients after orthognathic surgery with physiological positioning. The measurement points SNB, B point (X, Y), Pog (X, Y), and the angle of the ramus were measured on cephalometric photographs to assess skeletal stability preoperatively, immediately after operation, and one and two years postoperatively. In addition, we evaluated the clinical symptoms of disorders of the temporomandibular joint (TMJ). The analysis of the cephalometric photographs showed that SNB, B point X, and Pog X showed no significant differences among the postoperative time points. On the other hand, B point Y and Pog Y showed no significant differences throughout the study period. We compared the angle of the ramus before operation and two years postoperatively, and no significant difference was found. In addition, no cases showed any pathological symptoms of disorders of the TMJ two years postoperatively. The long-term stability after orthognathic surgery with physiological positioning was confirmed, and it seems to be a reliable orthognathic treatment in patients with mandibular prognathism.  相似文献   
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The feasibility of ventilation imaging with hyperpolarized (HP) 129Xe MRI has been investigated for quantitative and regional assessment of ventilation in spontaneously breathing mice. The multiple breath ventilation imaging technique was modified to the protocol of spontaneous inhalation of HP 129Xe delivered continuously from a 129Xe polarizer. A series of 129Xe ventilation images was obtained by varying the number of breaths before the 129Xe lung imaging. The fractional ventilation, r, was successfully evaluated for spontaneously breathing mice. An attempt was made to detect ventilation dysfunction in the emphysematous mouse lung induced by intratracheal administration of porcine pancreatic elastase (PPE). As a result, the distribution of fractional ventilation could be visualized by the r map. Significant dysfunction of ventilation was quantitatively identified in the PPE‐treated group. The whole‐lung r value of 0.34 ± 0.01 for control mice (N = 4) was significantly reduced, to 0.25 ± 0.07, in PPE‐treated mice (N = 4) (p = 0.038). This study is the first application of multiple breath ventilation imaging to spontaneously breathing mice, and shows that this methodology is sensitive to differences in the pulmonary ventilation. This methodology is expected to improve simplicity as well as noninvasiveness when assessing regional ventilation in small rodents. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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Abstract

Background: Recent advances in less-invasive surgery and electrode design allow for a high degree of hearing preservation (HP) after cochlear implantation (CI), although residual hearing still deteriorates in some patients. To date, the factors predictive of preserving residual hearing remain a controversial topic.

Objective: The aim of this study was to investigate the predictive factors, including the etiology of hearing loss (HL) as a patient-related factor, influencing residual HP after CI.

Methods: Forty-four patients (50 ears, 41 families) with residual acoustic hearing who underwent CI were included. Auditory thresholds before and at 6 months after initial activation were measured. Genetic testing was performed to identify the responsible genes for HL.

Results: We identified the cause of HL in 21 families (51.2%). HP was marginally correlated with age at implantation, while it was independent of pre-operative low-frequency hearing thresholds, cochlear duct length, and electrode length. We found that patients who had pathogenic variants in the CDH23, MYO7A, or MYO15A gene showed statistically better HP scores compared with patients with HL due to other causes (p?=?.002).

Conclusions: Identification of the etiology of HL using genetic testing is likely to facilitate the prediction of HP after implant surgery.  相似文献   
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