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31.
结合了当前造纸行业自动化的要求 ,介绍了纸浆配浆控制系统的设计与实现。系统具有功能强大、界面友好、调试容易、组态方便、运行稳定等优点  相似文献   
32.
The structural organization and fine distribution of the lymphatic networks in the periodontal tissues (gingiva, periodontal membrane, and alveolar process) and dental pulp of animals and humans were reviewed with special reference to histochemical examination by light and electron microscopy. The distinction between lymphatics and blood vessels was made on cryostat sections of undecalcified and calcified teeth treated with EDTA solution and whole mount preparations of periodontal membranes using 5'-nucleotidase (5'-Nase)-alkaline phosphatase (ALPase) double staining. This staining procedure allowed lymphatic vessels in the periodontal tissue and dental pulp to be differentiated from blood vessels. The specificity and localization of the enzyme reactions were confirmed by comparative histochemical studies of the same specimen with light microscopy and scanning or transmission electron microscopy. Well-developed 5'-Nase-positive lymphatic networks were observed on the tissue sections and whole mount preparations of the gingiva, periodontium, and dental pulp. More lymphatic vessels were seen in the root area of the periodontium than in the cervical area. In the dental pulp, lymphatic vessels were more numerous in the central part than in the peripheral odontoblastic layer. These distributions of the lymphatic capillary networks are discussed in relation to their ability to supply lymph to the teeth.  相似文献   
33.
The indirect immobilisation of Jagged-1 (Jagged-1) promoted osteogenic differentiation of human dental pulp cells (hDPs). Furthermore, the analysis of the Reactome pathway of RNA sequencing data indicates the upregulated genes involved with the extracellular matrix (ECM). Hence, our objective was to investigate the effects of Jagged-1 on proteomic profiles of human dental pulp stem cells (hDPSC). hDPSCs were cultured on the surface coated with human IgG Fc fragment (hFc) and the surface coated with rhJagged1/Fc recombinant protein-coated surface. Cells were differentiated to the osteogenic lineage using an osteogenic differentiation medium (OM) for 14 days, and cells cultured in a growth medium were used as a control. The protein component of the cultured cells was extracted into the cytosol, membrane, nucleus, and cytoskeletal compartment. Subsequently, the proteomic analysis was performed using liquid chromatography–tandem mass spectrometry (LC-MS). Metascape gene list analysis reported that Jagged-1 stimulated the expression of the membrane trafficking protein (DOP1B), which can indirectly improve osteogenic differentiation. hDPSCs cultured on Jagged-1 surface under OM condition expressed COL27A1, MXRA5, COL7A1, and MMP16, which played an important role in osteogenic differentiation. Furthermore, common matrisome proteins of all cellular components were related to osteogenesis/osteogenic differentiation. Additionally, the gene ontology categorised by the biological process of cytosol, membrane, and cytoskeleton compartments was associated with the biomineralisation process. The gene ontology of different culture conditions in each cellular component showed several unique gene ontologies. Remarkably, the Jagged-1_OM culture condition showed the biological process related to odontogenesis in the membrane compartment. In conclusion, the Jagged-1 induces osteogenic differentiation could, mainly through the regulation of protein in the membrane compartment.  相似文献   
34.
The regenerative endodontic procedure (REP) represents a treatment option for immature necrotic teeth with a periapical lesion. Currently, this therapy has a wide field of pre-clinical and clinical applications, but no standardization exists regarding successful criteria. Thus, by analysis of animal and human studies, the aim of this systematic review was to highlight the main characteristics of the tissue generated by REP. A customized search of PubMed, EMBASE, Scopus, and Web of Science databases from January 2000 to January 2022 was conducted. Seventy-five human and forty-nine animal studies were selected. In humans, the evaluation criteria were clinical 2D and 3D radiographic examinations. Most of the studies identified a successful REP with an asymptomatic tooth, apical lesion healing, and increased root thickness and length. In animals, histological and radiological criteria were considered. Newly formed tissues in the canals were fibrous, cementum, or bone-like tissues along the dentine walls depending on the area of the root. REP assured tooth development and viability. However, further studies are needed to identify procedures to successfully reproduce the physiological structure and function of the dentin–pulp complex.  相似文献   
35.
窦增文  魏明安 《矿冶》2015,24(3):22-24
基于氧气在黄铁矿浮选电化学反应中的作用,考察了p H为4.00、6.86、9.18、10.01和10.96五种缓冲溶液浮选体系下,矿浆溶氧量(DO)对黄铁矿浮选矿浆电位(Eh)和回收率的影响。研究表明,五种缓冲溶液体系下,Eh均随着DO的增加而增加,碱性条件下DO对Eh的影响较小;浮选回收率随DO的增加呈下降趋势,碱性条件下回收率的变化较大。  相似文献   
36.
福建某金银矿山是以银为主的金银矿,原矿银品位为128.87g/t,金品位为0.72g/t。设计采用浮选精矿氰化、锌粉置换法提金工艺。我们针对氰化厂设计中的工艺和工艺参数选取进行了分析探讨,对今后的工作具有一定的指导意义。  相似文献   
37.
山东某黄金矿山选矿厂由于浮选工艺流程中旋流器与取样机之间高差较大,以致溢流矿浆流速快、动能大,易造成对管路、弯头及取样机缓冲箱的冲击磨损。鉴于此,在旋流器溢流进入浮选粗选前增加快速浮选槽,以充分利用矿浆的动能,将原浮选工艺流程前增设无动力快速浮选工艺,并对改造后工艺流程结构进行了优化,将原三次扫选改为二次扫选。无动力快速浮选工艺的应用,不但节约了能耗,而且提高了金回收率,其由改造前的91.69%提高到93.06%,生产指标较好。  相似文献   
38.
研究了不同果型和果肉厚度辣椒在贮藏运输中的损耗及贮藏期间的营养品质变化,并分析了果型和果肉厚度与辣椒耐贮运性的关系。结果表明:线椒、朝天椒比牛角椒、尖椒耐运输;不同果型辣椒贮藏期间转色率、腐烂率和失水率差异显著,果肉厚度与失水率存在显著性负相关关系;果型比果肉厚度对辣椒贮藏期间维生素C、辣椒素、可溶性糖和可溶性蛋白质等营养成分含量变化的影响明显。   相似文献   
39.
本实验以红心火龙果茎为原料,通过单因素和正交实验对亚临界水提取红心火龙果茎多糖的工艺进行优化,并对提取的多糖进行抗氧化活性研究和结构鉴定,以确定红心火龙果茎的生物活性,并评价其体外抗氧化活性的强弱,从而为红心火龙果茎多糖的合理开发和应用提供理论依据。结果表明,亚临界水提取的最佳工艺参数:提取温度为140℃,提取时间为25 min,料液比为1∶50,多糖得率38.07%±0.15%。抗氧化性结果表明,火龙果茎多糖具有一定的抗氧化活性,对DPPH·和·OH清除率可达40.09%和95.15%。紫外和红外光谱分析表明,火龙果茎粗多糖不含蛋白质和核酸且具有典型的多糖红外吸收。   相似文献   
40.
以楠竹为原料生产竹浆粕,对水预水解和硫酸盐法蒸煮的工艺条件进行优化。结果表明:水预水解阶段最优工艺条件为P因子1000;硫酸盐蒸煮阶段最优工艺条件为H因子1000、用碱量17%(Na2O计)、硫化度20%。按此工艺条件所得的浆粕α-纤维素含量94.55%,黏度1096mL·g-1,细浆得率33.59%,卡伯值10.76,聚戊糖含量4.81%。  相似文献   
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