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11.
目的:将新疆南疆地区栽种的主要经济作物之一小白杏应用于化妆品领域,发挥其保持皮肤弹性、柔软和透明的功效。方法:以小白杏杏仁油为原料,运用正交实验设计,加入一定量的乳化剂,通过改变乳化温度、时间、转速,使油相与水相搅拌均匀。结果:最佳配方为:杏仁油13%,羊毛脂4%,蜂蜡3%,尿素3%,乳化剂1.5%,温度85℃,时间7 min,转速140 r/min。结论:以新疆小白杏杏仁油为主要原料,可研制适合于干性皮肤的防皲裂护手霜。  相似文献   
12.
In this research, ethanol production from carob pod extract (extract) using Zymomonas mobilis with medium optimized by Plackett–Burman (P–B) and response surface methodologies (RSM) was studied. Z. mobilis was recognized as useful for ethanol production from carob pod extract. The effects of initial concentrations of sugar, peptone, and yeast extract as well as agitation rate (rpm), pH, and culture time in nonhydrolyzed carob pod extract were investigated. Significantly affecting variables (P = 0.05) in the model obtained from RSM studies were: weights of bacterial inoculum, initial sugar, peptone, and yeast extract. Acid hydrolysis was useful to complete conversion of sugars to glucose and fructose. Nonhydrolyzed extract showed higher ethanol yield and residual sugar compared with hydrolyzed extract. Ethanol produced (g g−1 initial sugar, as the response) was not significantly different (P = 0.05) when Z. mobilis performance was compared in hydrolyzed and nonhydrolyzed extract. The maximum ethanol of 0.34 ± 0.02 g g−1 initial sugar was obtained at 30°C, initial pH 5.2, and 80 rpm, using concentrations (g per 50 mL culture media) of: inoculum bacterial dry weight, 0.017; initial sugar, 5.78; peptone, 0.43; yeast extract, 0.43; and culture time of 36 h.  相似文献   
13.
Upon activation by phytohemagglutine (PHA), T-lymphocytes (T-cells) express receptors for growth factors, insulin, IGF-1 and IL2 and become insulin sensitive. Diabetic ketoacidosis (DKA) is associated with in vivo emergence of these growth factor receptors without incubation with PHA. As DKA consists of multiple metabolic alterations, in addition to hyperglycemia, we investigated the in vitro effect of different concentrations of glucose (5, 15, and 30 mM) in isolated CD4 of human T-cells at various time intervals (0, 24, 48, and 72 h). Hyperglycemia, but not euglycemia, resulted in de novo emergence of growth factor receptors in a dose- and time-dependent fashion. The activation was also associated with incremental changes in GLUT 4, IRS-1, proinflammatory cytokines, and oxidative stress components. We propose that activation of T-cells with development of insulin receptors in hyperglycemic conditions may serve as a mechanism for control of glucose entry into these cells, thus, protecting them against glucose toxicity.  相似文献   
14.
Liver disorders may occur as a result of exposure to chemical compounds capable of inducing the oxidative stress and hepatic injuries. The aim of present study was to investigate the effects of flower extracts of B. Variegata for the treatment of liver injury induced by the CCl4. About 1 ml/kg body weight (b.w) of CCl4 was induced to experimental mice by intraperitoneal way for 14 days. The methanol and chloroform extracts (100, 200 and 300 mg/kg b.w) were administered to experimental animals for 14 days along with standard drug Silymarine (100 mg/kg b.w). The extracts alone showed no evidence of hepatic toxicity but animals exposed to CCl4 without the treatment with B. Variegata presented variations in levels of liver enzymes, antioxidant enzymes, proteins and blood cells as well as injuries in liver cells were also observed during histopathological study. However, after the treatments especially with 300 mg/kg b.w of methanol flower extracts levels of liver markers (ALT, AST and ALP), antioxidant enzymes and blood cells decreases and turned towards normal levels. Whereas level of total proteins and bilirubin was improved and damaged liver cells were repaired. The curative activity of flower extracts can be correlated to the higher potential of antioxidants and occurrence of Quercetin and some other organic compounds those were investigated from flower extracts of B. Variegata during HPLC and GC-MS analysis. The finding of this study supports the use of B. Variegata flower formulation in folk medicines.  相似文献   
15.
A series of 16 novel 1,2,4-triazine derivatives bearing hydrazone moiety (7a7p) have been designed, synthesized and evaluated for their activity to inhibit IL-1β and TNF-α production. All compounds are reported for the first time. The chemical structures of all compounds were confirmed by spectroscopic methods and elemental analyzes. Most of the synthesized compounds were proved to have potent anti-cytokine activity and low toxicity on PBMC and MCF-7 cell lines. Compounds 7f, 7k, 7l and 7j presented simultaneously good levels of inhibition of both cytokines. Moreover, compound 7l exhibited good anti-inflammatory effect in carrageenan-induced rat paw edema. The results of Western blotting demonstrated that the anti-cytokine potential of compound 7l is mainly mediated through the inhibition of p38 MAPK signaling pathway. Molecular docking was performed to position compound 7l into p38α binding site in order to explore the potential target. The information of this work might be helpful for the design and synthesis of novel scaffold toward the development of new therapeutic agent to fight against inflammatory diseases.  相似文献   
16.
In the present study, the biosynthesis of silver nanoparticles (AgNPs) using Neurospora intermedia, as a new non-pathogenic fungus was investigated. For determination of biomass harvesting time, the effect of fungal incubation period on nanoparticle formation was investigated using UV–visible spectroscopy. Then, AgNPs were synthesized using both culture supernatant and cell-free filtrate of the fungus. Two different volume ratios (1:100 and 1:1) of the culture supernatant to the silver nitrate were employed for AgNP synthesis. In addition, cell-free filtrate and silver nitrate were mixed in presence and absence of light. Smallest average size and highest productivity were obtained when using equal volumes of the culture supernatant and silver nitrate solution as confirmed by UV–visible spectra of colloidal AgNPs. Comparing the UV–visible spectra revealed that using cell-free filtrate for AgNP synthesis resulted in the formation of particles with higher stability and monodispersity than using culture supernatant. The absence of light in cell-free filtrate mediated synthesis led to the formation of nanoparticles with the lowest rate and the highest monodispersity. The presence of elemental silver in all prepared samples was confirmed using EDX, while the crystalline nature of synthesized particles was verified by XRD. FTIR results showed the presence of functional groups which reduce Ag+ and stabilize AgNPs. The presence of nitrate reductase was confirmed in the cell-free filtrate of the fungus suggesting the potential role of this enzyme in AgNP synthesis. Synthesized particles showed significant antibacterial activity against E. coli as confirmed by examining the growth curve of bacterial cells exposed to AgNPs.  相似文献   
17.
The distribution of Ia antigens on the surfaces of lymphocytes.   总被引:5,自引:0,他引:5  
The distribution of Ia antigens was studied on murine spleen lymphocytes by an ultrastructural technique employing deep freeze-etched replicas. Ia antigens were labeled on cells from appropriate congenic and recombinant strains of mice by incubating the cells with FITC-conjugated anti-Iak antibody, followed by ferritin-coupled Fab anti-FITC. Ia antigens were detected predominantly on immunoglobulin (Ig)-bearing B lymphocytes. Antigens coded for by the entire Ik region were present on the surfaces of 95% of the positive cells (from B10.BR mice) in densely packed microclusters. Ia specificities coded for by the I-A and I-C subregions (on 4R and B10.HTT mice) exhibited a more variable pattern, with 30 to 35% of the labeled cells having sparsely distributed Ia antigens in relatively discrete microclusters. Binding of anti-Iak antibody at 37 degrees C led to patch formation but not to capping. Modulation of surface Ig left Ia antigens diffusely distributed on the cell surface, indicating that these two membrane proteins are independent molecules.  相似文献   
18.
Transport of a uremic solute effected by a combined dialysis and ultrafiltration procedure in a hollow-fibre artificial kidney, is investigated theoretically under standard assumptions. An exact analytical solution for the concentration profile in a blood channel is obtained by using the method of separation of variables. The necessary requirement that the solution must tend to that of pure dialysis, in the limit ultrafiltration tending to zero, is fulfilled. Exact analytical expressions are derived for the eigenconstants of the solution. In using the solution, the solute clearance is emphasized. Diffusive and ultrafiltration components of the solute clearance are defined and studied. The combined procedure is examined for middle versus small molecules and for polyacrylonitrile versus cuprophan hollow-fibres.  相似文献   
19.
20.
A novel design of gold-coated iron oxide nanoparticles was fabricated as a potential delivery system to improve the efficiency and stability of d, l-sulforaphane as an anticancer drug. To this purpose, the surface of gold-coated iron oxide nanoparticles was modified for sulforaphane delivery via furnishing its surface with thiolated polyethylene glycol-folic acid and thiolated polyethylene glycol-FITC. The synthesized nanoparticles were characterized by different techniques such as FTIR, energy dispersive X-ray spectroscopy, UV-visible spectroscopy, scanning and transmission electron microscopy. The average diameters of the synthesized nanoparticles before and after sulforaphane loading were obtained ∼ 33 nm and ∼ 38 nm, respectively, when ∼ 2.8 mmol/g of sulforaphane was loaded. The result of cell viability assay which was confirmed by apoptosis assay on the human breast cancer cells (MCF-7 line) as a model of in vitro-cancerous cells, proved that the bare nanoparticles showed little inherent cytotoxicity, whereas the sulforaphane-loaded nanoparticles were cytotoxic. The expression rate of the anti-apoptotic genes (bcl-2 and bcl-xL), and the pro-apoptotic genes (bax and bak) were quantified, and it was found that the expression rate of bcl-2 and bcl-xL genes significantly were decreased when MCF-7 cells were incubated by sulforaphane-loaded nanoparticles. The sulforaphane-loaded into the designed gold-coated iron oxide nanoparticles, acceptably induced apoptosis in MCF-7 cells.  相似文献   
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