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991.
Tooth loss is a chronic disability, which makes it difficult for patients to perform essential tasks such as eating, communicating with others and socialising. Numerous studies have revealed and addressed the recent rapid development of various prosthodontic materials and treatment patterns. Oral rehabilitation with dentures exerts a great influence on people's daily life and has tremendous social implications. Dentures help to restore an individual's sense of normality and ability to interact normally. With the introduction and progression of implant technology, many troublesome issues can now be solved simply. Nowadays, more and more attention has been paid to new trends (implant‐assisted restoration and fixed prostheses). However, removable dentures may be a more appropriate solution under some circumstances, such as if they are a patient's preferred option, if remaining oral tissues are in poor condition, or if they provide the most cost‐effective form of treatment. Thus, removable dentures are still an option for the rehabilitation of oral function. The purpose of this article was to retrospectively review the applications of removable dentures and to emphasise their indispensable status.  相似文献   
992.
Bone defects caused by fractures or cancer-mediated destruction are debilitating. Chitosan is commonly used in scaffold matrices for bone healing, but rarely as a free drug. We demonstrate that free chitosan promotes osteoblast proliferation and osteogenesis in mesenchymal stem cells, increases osteopontin and collagen I expression, and reduces osteoclastogenesis. Chitosan inhibits invasion of endothelial cells, downregulating uPA/R, MT1-MMP, cdc42 and Rac1. Better healing of bone fractures with greater trabecular bone formation was observed in mice treated with chitosan. Chitosan induces apoptosis in osteotropic prostate and breast cancer cells via caspase-2 and -3 activation, and reduces their establishment in bone. Chitosan is pro-apoptotic in osteosarcoma cells, but not their normal counterpart, osteoblasts, or chondrosarcoma cells. Systemic delivery of chitosan does not perturb angiogenesis, bone volume or instinctive behaviour in pregnant mice, but decreases foetal length and changes pancreatic secretory acini. With certain controls in place, chitosan could be useful for bone trauma management.  相似文献   
993.
The objective was to explore the clinical value of contrast-enhanced ultrasound (CEUS) in locating the sentinel lymph node (SLN) in patients with early breast cancer. We screened 143 consecutive patients with breast cancer between July 2017 and August 2019. The number of SLNs identified by CEUS and dual labeling (blue dye and radiolabeled colloid) were recorded. The accuracy of CEUS plus fine-needle aspiration cytology (FNAC) was assessed. The rate of identification of SLNs with CEUS was 84.0% (121/144), and that of dual labeling was 97.92% (141/144). There was no significant association between non-enhancement (p = 0.060) or inhomogeneous enhancement (p = 0.468) and lymph node metastasis. The sensitivity and specificity of CEUS-SLNs plus FNAC was 78.38% and 100%, respectively. The technique of CEUS is a promising method for locating the axillary SLN. But it is hard to identify lymph node metastasis with CEUS alone. CEUS-SLNs plus FNAC is a sound technique for diagnosis of the metastasis of SLN.  相似文献   
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Objective:To investigate the network pharmacology of anti-tumor Chinese medicinal formulae and explain the synergistic mechanism of various active ingredients of Chinese medicinal formulae.Methods:We collected the anti?tumor Chinese medicinal formulae and chose several single herbs with the top frequency for further study.The chemical constituents of these herbs were downloaded from databases CNPC and Traditional Chinese Medicine Systems Pharmacology and were analyzed to set up the anti-tumor material basis.The genes regulated by these constituents were retrieved in Traditional Chinese Medicine integrated database and Comparative Toxicogenomics database.Results:We collected 65 anti-tumor Chinese medicinal formulae,and 4 single herbs were selected,including Licorice,Radix astragali,Panax ginseng,and Radix scutellariae,which consist of 172,70,293,and 92 known constituents,respectively.The constituent–gene network,protein–protein interaction network,gene–pathway enrichment network,and gene–disease network were constructed.Moreover,molecular docking was employed to clarify the interactions between active constituents and key drug targets(PTG2,epidermal growth factor receptor,peroxisome proliferator?activated receptor gamma,estrogen receptor 1,mammalian target of rapamycin,AKT1,mitogen-activated protein kinase 1 [MAPK1],peroxisome proliferator-activated receptor alpha,and MAPK8).Most of the constituents could act on multiple targets,whose structures mainly belong to alkaloids,flavonoids,and their glycosides,organic acids,or dianthrone,and their representative chemical constituents include narcissus glycosides,rutin,dauricine,scutellarin,baicalin,isoschaftoside,and leucovorin.Conclusion:The network mechanism of the effective constituents from traditional Chinese medicines(TCMs) for anti-tumor therapy was partially uncovered by using statistical methods,network pharmacology methods,and molecular docking methods.This study will provide important information for new drug design with multiple targets for anti-tumor therapy.  相似文献   
998.
Alantolactone (ALA), a sesquiterpene lactone isolated from several medicinal plants such as Inula helenium, has been identified to have attractive anticancer activity. However, its role in the inhibition of angiogenesis during tumor development remains unclear. In this study, we found ALA can inhibit the proliferation, motility, migration, and tube formation of human umbilical vein endothelial cells. ALA also restrained angiogenesis in chick embryo chorioallantoic membrane and delayed the growth of human MDA‐MB‐231 breast cancer xenograft in mice through angiogenesis inhibition. Furthermore, ALA suppressed the phosphorylation of vascular endothelial growth factor receptor 2 and its downstream protein kinase including PLCγ1, FAK, Src, and Akt in endothelial cells. Taken together, the antiangiogenic activity of ALA and its molecular mechanism are identified for the first time, indicating that ALA may be a potential drug candidate or lead compound for antiangiogenic cancer therapy.  相似文献   
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综述护理接近失误的识别与上报现状,并引用瑞士奶酪模型对接近失误的原因分析及干预进行归纳总结,主要包括组织影响、不安全监督、不安全行为先兆、不安全的行为,以期为减少接近失误、改善患者安全提供参考.  相似文献   
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