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Currently, most studies employ supervised learning techniques to train networks on three-dimensional tooth data to perform annotation tasks. However, these methods often perform poorly on cases of missing teeth, severe misalignments, or incomplete jaw structures, exhibiting weak generalization capabilities. To address these issues, a new approach based on a pre-trained SAM large model and prompt-based segmentation techniques was introduced. Initially, the model was fine-tuned on the MICCAI 3DTeethSeg'22 public dataset. Then, the three-dimensional dental models were projected onto multiple two-dimensional views, and the SAM network was utilized for image segmentation. After segmentation, each pixel's label was mapped back to the original three-dimensional triangular facets to complete the three-dimensional tooth segmentation. This approach was tested on 900 relatively ideal 3D upper and lower teeth data in the dataset, achieving results comparable to mainstream technologies. For complex cases such as missing teeth, misaligned teeth, and incomplete upper and lower jaws, it exhibited significantly better performance than existing technologies, showcasing enhanced generalizability and stability.(目前，大多研究采用有监督学习方法在牙齿的三维数据上训练网络，完成分割任务，但在处理缺牙、严重错位或颌部不完整的牙齿时效果不佳，泛化能力较弱。为此，提出了一种基于预训练分割一切模型（segment anything model，SAM）和提示分割技术的方法。首先，在2022年国际医学图像计算和计算机辅助干预会议（MICCAI 2022）的三维牙齿公开数据集上微调模型。然后，将三维牙齿模型投影至多个二维视图，利用SAM网络进行图像分割。再将每个像素的标签映射回原始的三维三角形面片，完成三维牙齿分割。在该数据集中，测试了900个较理想的三维上下牙数据，取得了与主流技术相当的结果。对于缺牙、牙齿错位以及上下颚不完整的复杂情况，本文方法表现出显著优于现有技术的效果，展示了更强的泛化能力和稳定性。)

14-3-3η can regulate the cell cycle, immunity, inflammation and the secretion of matrix metalloproteinases, while it may also be involved in the development of rheumatoid arthritis (RA) and promote bone injury. Therefore, the present meta-analysis focused on the dysregulated serum levels of 14-3-3η and its association with osteoporosis in patients with RA. Studies comparing the serum levels of 14-3-3η between patients with RA and healthy controls (HCs) or patients with RA with different bone mineral densities were retrieved from the EMBASE, Web of Science, PubMed and Cochrane databases. A total of 14 studies comprising 2,164 patients with RA and 1,136 HCs were included and analysed. Pooled analyses showed that the serum levels of 14-3-3η were enhanced in patients with RA compared with HCs [standardized mean difference (SMD): 1.34; 95% confidence interval (CI): 1.01-1.66; P<0.001]. In addition, the serum levels of 14-3-3η were also significantly higher in patients with RA with osteoporosis and osteopenia compared with those with normal bone mass (SMD: 1.96; 95% CI: 0.01-3.92; P=0.049 and SMD: 0.80; 95% CI: 0.09-1.52; P=0.028, respectively). Begg's and Egger's tests demonstrated that the publication bias for each evaluated indicator was low (all P>0.05). However, sensitivity analyses revealed that the findings were not very robust, which may be due to the omission of several individual studies. Overall, the present meta-analysis suggested that the serum levels of 14-3-3η were elevated and were associated with a higher risk of osteoporosis in patients with RA, thus supporting its potency as a circulating biomarker in the management of RA. [ABSTRACT FROM AUTHOR]

ABSTRACT To investigate the stress‐confinement effect on the dynamic crack propagation and energy evolution characteristics of heterogeneous granite under impact loading, a three‐dimensional equivalent grain‐based model (3D‐GBM) and FLAC3D‐PFC3D coupled modeling technique was used to establish a numerical model of a full‐scale true triaxial Hopkinson test system. The results indicate that: (1) A rate‐effect model of the dynamic strength enhancement factor for heterogeneous rocks under multiaxial static and dynamic combined loading was constructed, with lateral stress confinement enhancing the sensitivity of dynamic strength to the strain rate. (2) Axial stress reduces the crack initiation stress ratio (σci/σd) and damage stress threshold ratio (σcd/σd), reducing the time to their onset, while lateral stress has the opposite effect. (3) Lateral stress confinement helps dynamically adjust the types of microcracks within the rock, restricts the relative slip friction between particles, and decreases the kinetic energy of failure. (4) At approximately the same strain rate, the strain energy and slip friction energy sequentially increase under uniaxial, biaxial, and triaxial stress confinement. The mutual slip friction and movement between rock particles are more intense under biaxial stress confinement compared to uniaxial conditions. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the prognosis of advanced oral squamous cell carcinoma (AOSCC) patients undergoing neck dissection with sternocleidomastoid muscle (SCM) preservation and resection., Methods: From January 2013 to June 2017, a total of 235 AOSCC patients(stage Ⅲ and stage Ⅳ) who were diagnosed and underwent neck dissection at the Department of Oral and Maxillofacial Surgery, College and Hospital of Stomatology, Guangxi Medical University, were collected and followed-up. The differences in overall survival（OS）, local recurrence-free survival (LRFS) and regional recurrence-free survival (RRFS) were compared between different surgical procedures. SPSS 25.0 software package was used for statistical analysis., Results: Among 235 patients with postoperative follow-up, 101 patients retained the SCM during operation, and 134 patients had SCM removed. There was no significant difference in 5-year survival rate and 5-year regional recurrence rate between the SCM preservation group and the SCM resection group. Kaplan-Meier method of univariate analysis showed that SCM preservation or resection had no significant difference in OS, LRFS and RRFS. Cox multivariate regression analysis results showed that there was no significant difference between different surgical procedures in OS, LRFS and RRFS, while N stage and postoperative chemoradiotherapy were independent influencing factors for OS, LRFS and RRFS in AOSCC patients., Conclusions: Neck dissection with SCM preservation in AOSCC patients has no effect on survival and recurrence (including local recurrence and regional recurrence). It is feasible for AOSCC patients to undergo SCM-preserving neck dissection when metastatic cervical lymph nodes do not invade SCM. N stage and postoperative chemoradiotherapy affect the prognosis of AOSCC patients.