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Copyright of China Rubber Industry is the property of Editorial Office of China Rubber Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Practical Pharmacy & Clinical Remedies is the property of Editorial Department of Practical Pharmacy & Clinical Remedies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Plateau Meteorology is the property of Plateau Meteorology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Practical Pharmacy & Clinical Remedies is the property of Editorial Department of Practical Pharmacy & Clinical Remedies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Calcium silicate scaffolds have attracted more and more attention, because of their high biocompatibility, osteoinduction and osteoconduction activities, and a degree of biodegradation. However, due to the unstable osteogenic effect, fast degradation rate and poor mechanical properties of calcium silicate, it has not yet been used in clinical bone defect repair. OBJECTIVE: To review research progress in optimizing the performance of calcium silicate scaffolds, summarize the potential and insufficiency of the singlephase calcium silicate scaffolds applied in bone defect repair, and to explore the possibility of its use in clinical bone defect repair. METHODS: The search was performed on CNKI, Wanfang, PubMed, Elsevier, and Web of Science databases. With the keywords of “3D print, calcium silicate, osteogenesis, composite modification, angiogenesis, stress distribution, bone defect repairing” in Chinese and English, related articles in recent 20 years were retrieved. According to the inclusion and exclusion criteria, 83 papers were finally reviewed. Based on the final screening articles, the research progress and challenges of the performance optimization of calcium silicate based scaffolds in bone tissue engineering were systematically and comprehensively analyzed. RESULTS AND CONCLUSION: (1) Calcium silicate materials have a certain potential to promote osteogenic and angiogenic differentiation of bone marrow mesenchymal stem cells, and have certain degradability. Free Ca2+ and Si4+ can induce hydroxyapatite deposition, promote collagen- I secretion and differentiation of osteoblasts, thereby increasing bone mineral density and promoting mineralization. Now, it has become one of the most promising frontier research direction in the field of bone repair. (2) However, single-phase calcium silicate scaffolds are not fully suitable for bone tissue regeneration in bone defect area in terms of mechanical properties, biological activity, and degradation rate, so it has not been widely used in clinical practice. (3) At present, there are abundant studies on the performance optimization of calcium silicate scaffolds, but there is a lack of systematic summary. In this study, through a large number of literature summary and data extraction, the performance optimization methods of calcium silicate scaffolds are classified into two categories, namely, the optimization of scaffold structure and the optimization of scaffold material composition. (4) 3D printing technology has a prominent effect on the structure optimization of calcium silicate scaffolds. By accurately regulating the porosity and pore size of the scaffolds, 3D printing technology can make the calcium silicate scaffolds have better stress distribution mode and osteogenic and angiogenic effect. (5) The optimization of the composition of calcium silicate scaffolds is based on the influence of composite materials (including inorganic ions, molecules, organic molecules, and high polymer) on the biochemical structure of scaffolds in many aspects, so as to improve mechanical properties of calcium silicate scaffolds as well as the bioinduction properties of osteogenesis and angiogenesis. (6) In conclusion, the comprehensive use of 3D printing technology and composite modification of materials is a new idea for the studies of calcium silicate scaffolds in the field of bone repair. Based on the disadvantages of single-phase calcium silicate scaffolds in the application of bone defect repair, by optimizing and modifying the structure, composition and surface conditions of the calcium silicate scaffolds, a new type of calcium silicate-based tissue engineered bone scaffold, which can effectively promote osteogenic differentiation and bone mineralization, and whose mechanical properties and degradation rate could match the regeneration of bone tissue in bone defect area, will be explored. [ABSTRACT FROM AUTHOR]

目的 总结子宫内膜癌脑膜转移的临床特征、诊断及治疗方法。方法 对1例子宫内膜癌脑膜转移患者 的临床资料进行回顾性分析。结果 患者既往子宫内膜癌病史，因“发热伴头痛、恶心13 d”就诊。查体颈稍抵抗， 颌胸两横指。PET/CT示大脑镰及小脑周围脑膜代谢不均匀升高，胃底部胃壁弥漫性增厚、高代谢，胃小弯侧、肝门 处、后纵隔食管旁见多发淋巴结高代谢，考虑转移。脑脊液细胞学检查、胃部病理检查及免疫组化检查结果提示子 宫内膜癌转移。诊断为子宫内膜癌术后脑膜、胃、胃小弯侧、肝门处、后纵隔食管旁淋巴结转移。给予地塞米松联合 甘露醇降压、鞘内注射甲氨蝶呤化疗3周期，患者头痛症状缓解，但腰椎穿刺结果提示治疗效果欠佳，且出现Ⅲ度骨 髓抑制。后患者因经济困难拒绝继续治疗，自动出院。结论 子宫内膜癌脑膜转移罕见，患者症状常与颅内压升高 有关，预后差，确诊依靠患者既往病史及脑脊液细胞学检查，该病目前尚无统一的治疗标准。 [ABSTRACT FROM AUTHOR]

Copyright of Packaging & Food Machinery is the property of Packaging & Food Machinery Magazine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to solve the problem that the repair materials of operation tunnel structure are damaged again due to stress deformation, seepage erosion and other factors, PTB emulsion was used to modify the mortar. The effects of PTB emulsion on the mechanical properties, pliability, bond strength and impermeability were studied. Meanwhile, the modification mechanism was analyzed from the microstructure and pore morphology. The results show that the incorporation of PTB emulsion reduces the compressive strength of mortar and significantly improves the flexural strength. The compressive to flexural ratio of modified mortar decreases, the compression toughness index increases, so the pliability increases. With the increase of PTB emulsion content, the tensile bond strength and shear bond strength increase. The anti, permeability strength of modified mortar increases, water absorption rate decreases. Thus, the modified mortar has good waterproof performance. The incorporation of PTB emulsion reduces the total porosity, and the polymer membrane connects the hydration products and cement particles to form a dense spatial skeleton-matrix network structure. These change the strength of the mortar and are also the main reason for the improvement of pliability, bond strength and impermeability. This study aims to provide reference for the optimization design and practical application of polymer modified mortar. [ABSTRACT FROM AUTHOR]

Copyright of Southwest China Journal of Agricultural Sciences is the property of Editorial Department of Southwest China Journal of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The nonlinear characteristics of RF power amplifiers is an important research direction. To address the problem of high sampling rate in the amplifier predistortion system, this paper proposed a new brodaband power amplifier predistortion model. Firstly, it used the modulation wideband converter ( MWC ) based on sinusoidal frequency modulation ( SFM ) signal to spare the signal in the feedback loop, and then used the variable step size generalized adaptive matching tracking( VS-GSA MP ) algorithm to reconstruct the signal. The experimental results show that normalized mean squared error ( NSME ) is about 2 - 3 dB better than memory polynomial( MP) model and the general memory polynomial( GMP) model. The adjacent channel power radio can be improved to 21 dB. Good linear performance can be achieved at a lower sampling rate. [ABSTRACT FROM AUTHOR]

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Laser Technology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Liver cirrhosis can lead to continuous pathological elevation of portal venous pressure, resulting in various complications such as esophageal and gastric varices, ascites, hepatic encephalopathy, and secondary circulatory dysfunction. Multimodality therapy is the main treatment method for portal hypertension, among which surgical treatment is mainly used to control and prevent massive esophagogastric variceal bleeding. Currently, interventional therapy and liver transplantation have gradually become a routine method for surgical intervention and can significantly improve patients’ quality of life, but devascularization and shunt are still the mainstream surgical procedures. Each surgical strategy for cirrhotic portal hypertension has its own characteristics. It will be a trend in the future to evaluate patients’ general conditions and clinical features and select individualized treatment regimens to achieve the best treatment outcome. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ecology & Rural Environment is the property of Journal of Ecology & Rural Environment Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Southwest China Journal of Agricultural Sciences is the property of Editorial Department of Southwest China Journal of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

肝门部胆管癌恶性程度高,其最有效的治疗手段是根治性切除术。光动力疗法( PDT)是一种 创伤小、不良反应少的治疗方式,其基于分布在病理组织内的光敏剂,通过适当波长的光来启动活化过程,产生 光细胞毒性,进而对目标组织造成选择性破坏。PDT可提高患者生存率和生活质量,是治疗晚期癌症的新策 略,特别是肝门部胆管癌患者。该文就近年来PDT在肝门部胆管癌治疗中的应用及进展进行综述。 [ABSTRACT FROM AUTHOR]