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1.
Cell surface proteoglycans are known to be important regulators of many aspects of cell behavior. The principal family of transmembrane proteoglycans is the syndecans, of which there are four in mammals. Syndecan-1 is mostly restricted to epithelia, and bears heparan sulfate chains that are capable of interacting with a large array of polypeptides, including extracellular matrix components and potent mediators of proliferation, adhesion and migration. For this reason, it has been studied extensively with respect to carcinomas and tumor progression. Frequently, but not always, syndecan-1 levels decrease as tumor grade, stage and invasiveness and dedifferentiation increase. This parallels experiments that show depletion of syndecan-1 can be accompanied by loss of cadherin-mediated adhesion. However, in some tumors, levels of syndecan-1 increase, but the characterization of its distribution is relevant. There can be loss of membrane staining, but acquisition of cytoplasmic and/or nuclear staining that is abnormal. Moreover, the appearance of syndecan-1 in the tumor stroma, either associated with its cellular component or the collagenous matrix, is nearly always a sign of poor prognosis. Given its relevance to myeloma progression, syndecan-1-directed antibody—toxin conjugates are being tested in clinical and preclinical trials, and may have future relevance to some carcinomas.  相似文献   
2.
Since it is known that hyaluronic acid contributes to soft tissue growth, elasticity, and scar reduction, different strategies of producing HA have been explored in order to satisfy the current demand of HA in pharmaceutical products and formulations. The current interest deals with production via bacterial and yeast fermentation and extraction from animal sources; however, the main challenge is the right extraction technique and strategy since the original sources (e.g., fermentation broth) represent a complex system containing a number of components and solutes, which complicates the achievement of high extraction rates and purity. This review sheds light on the main pathways for the production of HA, advantages, and disadvantages, along with the current efforts in extracting and purifying this high-added-value molecule from different sources. Particular emphasis has been placed on specific case studies attempting production and successful recovery. For such works, full details are given together with their relevant outcomes.  相似文献   
3.
This study determined the effects of exogenous hyaluronic acid (HA) on the biomechanical and biochemical properties of self-assembled bovine chondrocytes, and investigated biophysical and genetic mechanisms underlying these effects. The effects of HA commencement time, concentration, application duration and molecular weight were examined using histology, biomechanics and biochemistry. Additionally, the effects of HA application on sulphated glycosaminoglycan (GAG) retention were assessed. To investigate the influence of HA on gene expression, microarray analysis was conducted. HA treatment of developing neocartilage increased compressive stiffness onefold and increased sulphated GAG content by 35 per cent. These effects were dependent on HA molecular weight, concentration and application commencement time. Additionally, applying HA increased sulphated GAG retention within self-assembled neotissue. HA administration also upregulated 503 genes, including multiple genes associated with TGF-β1 signalling. Increased sulphated GAG retention indicated that HA could enhance compressive stiffness by increasing the osmotic pressure that negatively charged GAGs create. The gene expression data demonstrate that HA treatment differentially regulates genes related to TGF-β1 signalling, revealing a potential mechanism for altering matrix composition. These results illustrate the potential use of HA to improve cartilage regeneration efforts and better understand cartilage development.  相似文献   
4.
Salmon cartilage proteoglycan fractions have recently gained favor as ingredients of functional food and cosmetics. An optimal hot water method to extract proteoglycan from salmon cartilage has recently been developed. The extracted cartilage includes hyaluronan and collagen in addition to proteoglycan as counterparts that interact with each other. In this study, biochemical analyses and atomic force microscopical analysis revealed global molecular images of proteoglycan in the hot water extract. More than seventy percent of proteoglycans in this extract maintained their whole native structures. Hyaluronan purified from the hot water extract showed a distribution with high molecular weight similar to hyaluronan considered to be native hyaluronan in cartilage. The current data is evidence of the quality of this hot water cartilage extract.  相似文献   
5.
郑磊  金秀明  赵玉红 《食品科学》2010,31(16):61-66
以鹿茸为原料,应用超声波辅助盐法提取糖胺聚糖。在单因素试验基础上,选取超声波功率、超声波处理时间、液料比为自变量,鹿茸糖胺聚糖提取率为响应值,应用Box-Behnken 旋转回归设计对提取工艺进行优化。结果表明:最优提取条件为超声波处理时间19.57min、超声波功率401.2W、液料比43.8:1(mL/g),在此条件下,鹿茸糖胺聚糖实际提取率为3.29%。与蛋白酶提取法相比,该方法糖胺聚糖提取率较高,简便易行并能降低生产成本。  相似文献   
6.
探讨鸡内金粘多糖提取过程中脱蛋白、脱盐、脱色方法及多糖组分的初步分级。确定了酶解加三氯乙酸法和氧化铝法为鸡内金粘多糖脱蛋白和脱色的方法,选截留量1000的透析膜来脱盐。得到了75%、55%两种乙醇浓度的鸡内金粘多糖的分级沉淀。关键词脱蛋白脱色素脱盐粘多糖分级  相似文献   
7.
以鱼鳔为原料,通过枯草中性蛋白酶和胰蛋白酶双酶酶解提取糖胺聚糖,在单因素实验的基础上采用响应曲面法对提取条件进行优化,通过理化分析及UV、IR分析其性质和化学结构特征,并评价其吸湿保湿性。结果表明:酶法提取鱼鳔糖胺聚糖的最佳工艺条件:料液比1∶20 g∶m L、酶解时间4 h,酶解温度50℃,酶用量7%,酶解p H8,最优条件下鱼鳔糖胺聚糖粗品得率为1.19%,糖胺聚糖含量为19.09%;红外吸收光谱检测表明,其具有典型的糖胺聚糖特征吸收峰,且含有α糖苷键的吡喃糖环结构;鱼鳔糖胺聚糖具有良好的吸湿保湿性,总体吸湿保湿性优于壳聚糖、海藻酸钠等常规保湿剂。综上表明,鱼鳔糖胺聚糖作为一种天然的保湿剂具有一定的应用前景。   相似文献   
8.
Complexes of glycosaminoglycans and certain cationic polymers have been identified which provide utility in skin and hair care applications. The combination of biologically engineered hyaluronic acid and the cationic cellulose polymer, polyquaternium-10, results in a unique, stable, multifunctional, association complex with enhanced polymer functionality. Complexation of the anionic and cationic polysaccharide polymers renders hyaluronic acid substantive to keratin, as evidenced by zeta potential changes of the surface charge of hair via electrokinetic streaming potential measurements. Radiolabelling techniques show as much as a ten-fold increase in bound hyaluronic acid on hair after water rinsing. The resulting 'enhanced'substantivity of hyaluronic acid, as part of the complex, thus extends the time hyaluronic acid remains in contact with keratinous surfaces, prolonging its humectant, moisturizing and skin-smoothening effects.  相似文献   
9.
响应面法优化四角蛤蜊糖胺聚糖提取工艺研究   总被引:1,自引:0,他引:1  
在单因素试验的基础上,利用SAS软件和响应面分析相结合的方法对四角蛤蜊糖胺聚糖的提取工艺进行了优化,通过试验得到了二次多项式回归模型,模型的相关系数R2=0.976 2,该模型能较好的反映各因素与响应值之间的关系。最佳提取工艺的条件是水料比3∶1,酶解时间3.5 h,酶添加量1.0%。在此条件下,糖胺聚糖的提取率可达0.448%。  相似文献   
10.
以国产大宗低值海参——海地瓜为原料,以酶解结合超滤技术制备海参多糖.通过单因素试验及响应面试验研究酶解过程各因素对海参多糖蛋白含量的影响,并对酶解条件进行优化.试验结果表明:成功建立了预测海参多糖中蛋白含量的数学模型;复合蛋白酶酶解的最优条件是:pH 7.0、温度51℃、底物质量分数4.82%、酶与底物的质量比4.08%、时间12h.经优化,制备了低蛋白含量海参多糖,多糖蛋白含量由19.91%降至2.41%.  相似文献   
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