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991.
采用毛用活性染料和棉用乙烯砜/一氯均三嗪双活性基一氯均三嗪和双一氯均三嗪活性染料对大豆蛋白/牛奶酪素蛋白/聚乙烯醇共混纤维进行染色初探。探讨了染料对双蛋白纤维的上染率、固着率和染色牢度,比较了双蛋白纤维和大豆蛋白纤维的染色性能。结果表明,毛用活性染料不适合双蛋白纤维的染色,棉用活性染料适合双蛋白纤维的染色,且染色织物具有较好的色牢度。  相似文献   
992.
本研究以花生脱脂粉为原料,采用低温冷沉法分离制备了花生蛋白富集组分,花生蛋白富集组分与麦芽糊精以1:1混合,在60℃湿度79%的干热条件下,花生球蛋白富集组分反应1~7 d,伴花生球蛋白富集组分反应8~24 h,运用SDS-PAGE电泳表征了花生蛋白富集组分与多糖接枝反应进行的情况,采用热特性与荧光光谱等手段表征了花生分离蛋白与多糖的接枝反应产物结构特性的变化。SDS-PAGE分析表明花生球/伴球蛋白富集组分已经在干热条件下与麦芽糊精发生交联反应生成大分子的接枝产物,伴花生球蛋白相比花生球蛋白富集组分更易与麦芽糊精发生美拉德反应。花生蛋白富集组分与麦芽糊精的混合或者接枝反应显著地改善了蛋白组分的热稳定性。花生蛋白富集组分随着糖接枝反应程度的加深其空间结构先变得松散,而后又再次变得更加紧凑。  相似文献   
993.
Protein trafficking is altered when normal cells acquire a tumor phenotype. A key subcellular compartment in regulating protein trafficking is the Golgi apparatus, but its role in carcinogenesis is still not well defined. Golgi phosphoprotein 3 (GOLPH3), a peripheral membrane protein mostly localized at the trans-Golgi network, is overexpressed in several tumor types including glioblastoma multiforme (GBM), the most lethal primary brain tumor. Moreover, GOLPH3 is currently considered an oncoprotein, however its precise function in GBM is not fully understood. Here, we analyzed in T98G cells of GBM, which express high levels of epidermal growth factor receptor (EGFR), the effect of stable RNAi-mediated knockdown of GOLPH3. We found that silencing GOLPH3 caused a significant reduction in the proliferation of T98G cells and an unexpected increase in total EGFR levels, even at the cell surface, which was however less prone to ligand-induced autophosphorylation. Furthermore, silencing GOLPH3 decreased EGFR sialylation and fucosylation, which correlated with delayed ligand-induced EGFR downregulation and its accumulation at endo-lysosomal compartments. Finally, we found that EGF failed at promoting EGFR ubiquitylation when the levels of GOLPH3 were reduced. Altogether, our results show that GOLPH3 in T98G cells regulates the endocytic trafficking and activation of EGFR likely by affecting its extent of glycosylation and ubiquitylation.  相似文献   
994.
The membrane fouling phenomenon, reflected with various fouling characterization in the membrane bioreactor(MBR) process, is so complicated to distinguish. This paper proposes a multivariable identification model(MIM) based on a compacted cascade neural network to identify membrane fouling accurately. Firstly, a multivariable model is proposed to calculate multiple indicators of membrane fouling using a cascade neural network, which could avoid the interference of the overlap inputs. Secondly, a...  相似文献   
995.
The uncertainty about the fouling behaviour is one of the main reasons why plate and frame heat exchangers are not more widely installed in the chemical process industry and in power generating facilities. In the present investigation, the deposition of calcium sulphate in two different plate heat exchanger geometries was investigated. The deposition process was deliberately focused on crystallisation fouling through the installation of an in-line filter and the mode of preparation of the test solution. The investigated operating parameters were solution concentration, flow velocity, and bulk and surface temperatures. The heat exchangers were opened after each experiment to record the appearance and distribution of the deposits. The key result of this investigation is the strong correlation between the plate design and the tendency for deposit formation.  相似文献   
996.
The functional properties of low- and high-M.W. (LMW and HMW, respectively) acidic subunits and the basic subunit separated from the 11S soy protein fraction were studied and compared with the functional properties of the 11S fraction. Among the functional properties investigated were solubility, emulsification, and viscosity. The results showed that the LMW acidic subunit had higher solubility than the HMW acidic subunit. Among all the samples, the LMW subunit separated by using β-mercaptoethanol (ME) was the most soluble, with a solubility of 98–100% at a pH of 6–12. The solubility profile of the HMW subunit followed a pattern similar to the solubility of 11S. The lowest solubility was observed around pH values in the range close to the isoelectric point for both the LMW and HMW subunit. The basic subunit was not soluble in the pH range 3–10; however, the solubility increased more than 50% at pH 13 compared to the solubility at pH 10. The emulsification capacity of all subunits was higher than 11S in the following descending order: LMW, basic, HMW, 11S. Emulsification activity and stability of the subunits were greater than those of the 11S samples at room temperature and 95°C. With the exception of the LMW subunit separated with ME, the subunits had a higher viscosity than 11S. The basic subunit separated with sodium bisulfite had the highest viscosity of all the samples tested.  相似文献   
997.
The term heterotopic ossification (HO) describes bone formation in tissues where bone is normally not present. Musculoskeletal trauma induces signalling events that in turn trigger cells, probably of mesenchymal origin, to differentiate into bone. The aetiology of HO includes extremely rare but severe, generalised and fatal monogenic forms of the disease; and as a common complex disorder in response to musculoskeletal, neurological or burn trauma. The resulting bone forms through a combination of endochondral and intramembranous ossification, depending on the aetiology, initiating stimulus and affected tissue. Given the heterogeneity of the disease, many cell types and biological pathways have been studied in efforts to find effective therapeutic strategies for the disorder. Cells of mesenchymal, haematopoietic and neuroectodermal lineages have all been implicated in the pathogenesis of HO, and the emerging dominant signalling pathways are thought to occur through the bone morphogenetic proteins (BMP), mammalian target of rapamycin (mTOR), and retinoic acid receptor pathways. Increased understanding of these disease mechanisms has resulted in the emergence of several novel investigational therapeutic avenues, including palovarotene and other retinoic acid receptor agonists and activin A inhibitors that target both canonical and non-canonical signalling downstream of the BMP type 1 receptor. In this article we aim to illustrate the key cellular and molecular mechanisms involved in the pathogenesis of HO and outline recent advances in emerging molecular therapies to treat and prevent HO that have had early success in the monogenic disease and are currently being explored in the common complex forms of HO.  相似文献   
998.
The granule-bound starch synthase I (GBSSI) encoded by the waxy gene is responsible for amylose synthesis in the endosperm of wheat grains. In the present study, a novel Wx-B1 null mutant line, M3-415, was identified from an ethyl methanesulfonate-mutagenized population of Chinese tetraploid wheat landrace Jianyangailanmai (LM47). The gene sequence indicated that the mutated Wx-B1 encoded a complete protein; this protein was incompatible with the protein profile obtained using sodium dodecyl sulfate–polyacrylamide gel electrophoresis, which showed the lack of Wx-B1 protein in the mutant line. The prediction of the protein structure showed an amino acid substitution (G470D) at the edge of the ADPG binding pocket, which might affect the binding of Wx-B1 to starch granules. Site-directed mutagenesis was further performed to artificially change the amino acid at the sequence position 469 from alanine (A) to threonine (T) (A469T) downstream of the mutated site in M3-415. Our results indicated that a single amino acid mutation in Wx-B1 reduces its activity by impairing its starch-binding capacity. The present study is the first to report the novel mechanism underlying Wx-1 deletion in wheat; moreover, it provided new insights into the inactivation of the waxy gene and revealed that fine regulation of wheat amylose content is possible by modifying the GBSSI activity.  相似文献   
999.
Patients at a high risk for sudden cardiac death (SCD) without previous history of cardiovascular disease remain a challenge to identify. Atherosclerosis and prothrombotic states involve inflammation and non-cardiac tissue damage that may play active roles in SCD development. Therefore, we hypothesized that circulating proteins implicated in inflammation and tissue damage are linked to the future risk of SCD. We conducted a prospective nested case–control study of SCD cases with verified myocardial infarction (N = 224) and matched controls without myocardial infarction (N = 224), aged 60 ± 10 years time and median time to event was 8 years. Protein concentrations (N = 122) were measured using a proximity extension immunoassay. The analyses revealed 14 proteins significantly associated with an increased risk of SCD, from which two remained significant after adjusting for smoking status, systolic blood pressure, BMI, cholesterol, and glucose levels. We identified leukotriene A4 hydrolase (LTA4H, odds ratio 1.80, corrected confidence interval (CIcorr) 1.02–3.17) and hepatocyte growth factor (HGF; odds ratio 1.81, CIcorr 1.06–3.11) as independent risk markers of SCD. Elevated LTA4H may reflect increased systemic and pulmonary neutrophilic inflammatory processes that can contribute to atherosclerotic plaque instability. Increased HGF levels are linked to obesity-related metabolic disturbances that are more prevalent in SCD cases than the controls.  相似文献   
1000.
杨林峰  赵剑曦 《精细化工》2007,24(6):539-543
用天然大豆蛋白和葡甘聚糖,利用羟氨反应使蛋白质分子的侧链氨基与多糖分子的末端不饱和羰基反应生成稳定的共价键,进而形成以多羟基葡甘聚糖为亲水基,大豆蛋白为疏水基的新型两亲分子。结果表明,葡甘聚糖改性大豆蛋白是良好的药用乳化剂,制成的O/W乳状液稳定性明显优于Tween-60制成的乳状液。  相似文献   
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