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The box girder is an important structure widely used in the ship and marine engineering, but the fracture problem is not extensively investigated. The paper adopts the stress intensity factor (SIF) as the fracture parameter to perform the threedimensional (3D) mixed mode fracture assessment of the box girder structure with crack damage. The bending load, torsion load and side load are first introduced to study box girder fracture behavior. And the related influencing factors including crack lengths, crack angles and combined loads are investigated emphatically. Besides, the crack growth angle is also investigated to evaluate the crack propagation behavior. The results show that the load types have a significant effect on the crack propagation. The effect of bending load is generally greater than torsion load. The combined effect of bending and torsion loads may be considered adopting a linear superposition principle under transverse crack and larger angle crack. Additionally, the SIFs produced by torsion load only have a slight change with the increased crack angles. When the side load is added, the area near the crack upper surface will be easy to occur unstable expansion. These findings from the present study will provide a guiding significance to evaluate the crack propagation of box girder under combined loads. [ABSTRACT FROM AUTHOR]

Lung cancer is a major public health problem worldwide, with high rates of morbidity and mortality. It often coexists with chronic obstructive pulmonary disease (COPD), the diagnosis and management of which often receives insufficient attention. In particular, the presence of COPD has significant implications for the clinical management of lung cancer patients. This review systematically assesses the influence of COPD on the efficacy of immunotherapy and the occurrence of immune-related adverse events in patients with lung cancer, identifies existing challenges and proposes avenues for future research in this field.

Dentin dysplasia type Ⅱ (DD-Ⅱ) is a subtype of hereditary dentin disorders. The dentin sialophosphoprotein (DSPP) gene has been revealed to be the causative gene, whose mutations could affect the normal tooth development process. The lesions involve both deciduous and permanent dentition, mainly manifested as tooth discoloration, attrition and even the subsequent malocclusion. If not treated in time, it will significantly affect the physical and psychological health of patients. The disease is difficult to be diagnosed in clinic accurately as its low incidence and hidden manifestations. The present article aims to discuss the clinical and radiographic characteristics, diagnosis, treatment of DD-Ⅱ, in order to improve the overall understanding on DD-Ⅱ for clinicians.

The biological samples of oral genetic diseases and rare diseases are extremely precious. Collecting and preserving these biological samples are helpful to elucidate the mechanisms and improve the level of diagnose and treatment of oral genetic diseases and rare diseases. The standardized construction of biobanks for oral genetic diseases and rare diseases is important for achieving these goals. At present, there is very little information on the construction of these biobanks, and the standards or suggestions for the classification and coding of biological samples from oral and maxillofacial sources, and this is not conducive to the standardization and information construction of biobanks for special oral diseases. This consensus summarizes the background, necessity, principles, and key points of constructing the biobank for oral genetic diseases and rare diseases. On the base of the group standard "Classification and Coding for Human Biomaterial" (GB/T 39768-2021) issued by the National Technical Committee for Standardization of Biological Samples, we suggest 76 new coding numbers for different of biological samples from oral and maxillofacial sources. We hope the consensus may promote the standardization, and smartization on the biobank construction as well as the overall research level of oral genetic diseases and rare diseases in China.

Objective: To investigate the etiology, prevention and treatment status, and their corresponding regional differences of the patients with liver cirrhosis in China, in order to provide scientific basis for the development of diagnosis and control strategies in China. Methods: Clinical data of patients diagnosed with liver cirrhosis for the first time through January 1, 2018 to December 31, 2020 from 50 hospitals in seven different regions of China were collected and analyzed retrospectively, and the difference of etiology, treatment, and their differences in various regions were analyzed. Results: A total of 11 861 cases with liver cirrhosis were included in the study. Thereinto, 5 093 cases (42.94%) were diagnosed as compensated cirrhosis, and 6 768 cases (57.06%) had decompensated cirrhosis. Notably, 8 439 cases (71.15%) were determined as chronic hepatitis B-caused cirrhosis, 1 337 cases (11.27%) were alcoholic liver disease, 963 cases (8.12%) were chronic hepatitis C, 698 cases (5.88%) were autoimmune liver disease, 367 cases (3.09%) were schistosomiasis, 177 cases (1.49%) were nonalcoholic fatty liver, and 743 cases (6.26%) of other types of liver disease. There were significant differences in the incidence of chronic hepatitis B, chronic hepatitis C, alcoholic liver disease, fatty liver, schistosomiasis liver disease, and autoimmune liver disease among the seven regions ( P <0.001). Only 1 139 cases (9.60%) underwent endoscopic therapy, thereinto, 718 cases (6.05%) underwent surgical therapy, and 456 cases (3.84%) underwent interventional therapy treatment. In patients with compensated liver cirrhosis, 60 cases (0.51%) underwent non-selective β receptor blockers(NSBB), including 59 cases (0.50%) underwent propranolol and 1 case (0.01%) underwent carvedilol treatment. In patients with decompensated liver cirrhosis, 310 cases (2.61%) underwent NSBB treatment, including 303 cases (2.55%) underwent propranolol treatment and 7 cases (0.06%) underwent carvedilol treatment. Interestingly, there were significant differences in receiving endoscopic therapy, interventional therapy, NSBB therapy, splenectomy and other surgical treatments among the seven regions ( P <0.001). Conclusion: Currently, chronic hepatitis B is the main cause (71.15%) of liver cirrhosis in several regions of China, and alcoholic liver disease has become the second cause (11.27%) of liver cirrhosis in China. The three-level prevention and control of cirrhosis in China should be further strengthened.

Circadian rhythm is regulated by circadian clock, which is formed by the body response to external cyclic stimuli through the endogenous circadian clock. Circadian rhythm disturbance is closely related to the risks of a variety of diseases, and its impact on oral health cannot be ignored. Exploring the relationship and related molecular mechanism between circadian rhythm and dental hard tissues development are helpful to deeply understand the pathogenesis of developmental defects on these tissues, which could provide a theoretical basis for prevention and treatment on disorders of dental hard tissues. In order to provide guidance for the disease prevention and treatment, based on the summarization of current research progress, this paper focuses on the involvement of biorhythm in the development of tooth hard tissues as well as the disturbance of circadian rhythm on the formation of enamel and dentin, and analyzes the related regulating mechanism of circadian rhythm and genes during the development of tooth hard tissues.

Diabetes mellitus is a relative contraindication of dental implant therapy, that limits the application of implant therapy severely. Diabetic status often leads to secondary vascular and bone lesions, which affect treatment adversely and lead to an increased failure rate. Therefore, how to implement implant therapy for diabetic patients has become a difficult question for dentists. According to the research and experience over the years on diabetic patients, and referring to the current research progress on this topic, the authors will discuss the clinical characteristics of diabetic patients and the details of treatment process, for reference.

Objective: To investigate the effect of guided bone regeneration (GBR) on marginal bone loss (MBL) in the region of the mandibular posterior tooth by using a retrospective cohort study, in order to provide reference for clinical practice. Methods: The research subjects were patients who received dental implants from October 2008 to June 2011 in the region of the mandibular posterior tooth at the Department of Oral Implantology, School of Stomatology, The Fourth Military Medical University. According to whether GBR was performed or not and the time of implant insertion, the patients were divided into the controls group (patients without bone grafting), simultaneous GBR implantation group, and delayed GBR implantation group. On this basis, the MBL was measured according to radiographs by comparing the marginal bone level from that of immediate postoperation 10 years ago. General data was collected and compared among groups, including modified plaque index (mPI), modified sulcus bleeding index (mSBI), probing depth (PD), and gingival papilla height. Results: The controls group (patients without bone grafting), implantation group, and delayed GBR implantation group followed 58, 76, 26 implants in 26, 32, 13 patients aging at (46.5±9.9), (45.5±10.7), (58.3±6.4) respectively. The duration of the follow-up was (11.2±0.7), (11.1±0.8), (11.1±0.9) years respectively. The 10-year implant survival rate was 100% (58/58), 100% (76/76), 100% (26/26). The MBL was (0.91±0.28), (0.84±0.27), (1.01±0.27) mm respectively. The MBL difference of patients with simultaneous GBR implantation and delayed GBR implantation showed statistical significance ( P <0.05), but these two groups showed no statistical significance compared with the controls group ( P >0.05). The mPI, mSBI, PD, and gingival papilla height of the three groups all had no significance on statistics ( P >0.05). Conclusions: It can be concluded that there is no difference in long-term marginal bone resorption between simultaneous and delayed implantation with or without GBR (using autologous blood mixed with granular bone meal) in the posterior mandibular area.