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21.
《Nutrition Research》1986,6(6):673-688
The metabolic effects of cellulose on insulin receptor interaction (IRI) was studied at 10 and 20 percent protein levels in male weanling Sprague Dawley rats. One hundred and four (104) rats were divided into 8 groups of 13 each and randomly put on various dietary treatments as already reported elsewhere [Fed. Proceed. 1985; 44(5):6367]. Animals for radioreceptor studies (n=5 per group) were fed for 8 weeks. Blood samples were obtained from the rats via cardiac puncture under nembutal anesthesia. Erythrocyte IRI and serum insulin levels (IN) were measured by a standardized radioreceptor assay (10) and radioimmunoassay respectively. Fiber and protein intake had significant effect on IRI (p<0.01) and IN (p<0.05). Specific percent 125I-insulin binding (SIB) was higher in the 20% protein group at all fiber levels while in the fiber free groups higher SIB was observed in the 10% protein group (p<0.01). At both protein levels, maximum SIB was observed at the 5% fiber level. While SIB in the absence of fiber was observed to be strictly a function of receptor site concentration (Ro) binding in the presence of fiber was a function of both Ro and empty site affinity (Ke). Fiber intake appears to interfere with the negative cooperative nature of the receptor sites by slowing down the rate of changing affinity from a high Ke to the limiting Kf (filled site affinity) state as receptor occupancy [Y=Long [B]/Ro] increases. While no significant effect of calorie was observed on e and f, caloric intake (Cal) showed a positive correlation (r=0.8, p<0.001) with IN and a negative (r=0.32, p<0.02) correlation with Ro. It is concluded that: (I) diet can modulate erythrocyte IRI in growing animals, (II) the metabolic effects of dietary fiber depend on the combination with other nutrients, (III) adequate protein nutrition is essential for plasma membrane function at the cell receptor level in growing animals and (IV) the increase in IRI by dietary fiber is a function of both e, Ro and the sustenance of the average affinity of these homogeneous class of receptor sites in the high affinity states. 相似文献
22.
Adenoviruses can cause infections in people of all ages at all seasons of the year. Adenovirus infections cause mild to severe illnesses. Children, immunocompromised patients, or those with existing respiratory or cardiac disease are at higher risk. Unfortunately, there are no commercial drugs or vaccines available on the market for adenovirus infections. Therefore, there is an urgent need to discover new antiviral drugs or drug targets for adenovirus infections. To identify potential antiviral agents for adenovirus infections, we screened a drug library containing 2138 compounds, most of which are drugs with known targets and past phase I clinical trials. On a cell-based assay, we identified 131 hits that inhibit adenoviruses type 3 and 5. A secondary screen confirmed the antiviral effects of 59 inhibitors that inhibit the replication of adenoviruses type 3 or 5. Most of the inhibitors target heat shock protein, protein tyrosine kinase, the mTOR signaling pathway, and other host factors, suggesting that these host factors may be essential for replicating adenoviruses. Through this study, the newly identified adenovirus inhibitors may provide a start point for developing new antiviral drugs to treat adenovirus infections. Further validation of the identified drug targets can help the development of new therapeutics against adenovirus infections. 相似文献
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目的采用液相色谱/光电二极管阵列检测器/质谱(HPLC/DAD/MS)联用技术鉴定何首乌中同时存在顺式和反式-二苯乙烯苷,并分别测定其含量,同时考察二苯乙烯苷对光的稳定性。方法采用反相UltimateXB-C18(4.6mm×250mm,5μm)色谱柱,甲醇-10mmol·L-1醋酸铵水溶液二元线性梯度洗脱,流速为1mL·min-1,离子阱质谱(IT-MS)鉴定出何首乌中同时存在顺式和反式-二苯乙烯苷,DAD检测器做定量分析,检测波长为280nm。结果首次证实何首乌中不仅存在反式-二苯乙烯苷,还存在顺式-二苯乙烯苷。顺式和反式-二苯乙烯苷分别在0.252~4.022μg(r=0.9999)和2.14~34.36μg(r=0.9993)内线性关系良好,测得顺式、反式二苯乙烯苷在生首乌和制首乌中的含量分别为0.058%,1.56%和0.027%,0.84%。光照条件下何首乌中的反式-二苯乙烯苷部分转化成顺式结构,但总含量不变。结论此方法可以很好地将何首乌中的顺式和反式-二苯乙烯苷分离并准确测定其含量,灵敏度高,光照条件下何首乌中的反式-二苯乙烯苷会部分转化成顺式结构。 相似文献
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目的:建立毛细管区带电泳法测定三白草中芦丁和槲皮素的含量.方法:采用石英毛细管(50 cm×50μm i.d.,有效长度为41 cm),以15 mmol/L硼砂(pH 8.5)为背景电解质,运行电压28 kV,重力进样10cm,12 s,紫外检测波长254nm.结果:芦丁在0.5-100 mg/L浓度范围内线性关系良好(r=0.999 3),平均回收率为97.2%.槲皮素在2.0-200mg/L浓度范围内线性关系良好(r=0.999 6),平均回收率为96.0%.结论:该法简便、快速、污染小,适用于三白草药材中芦丁和槲皮素含量的测定. 相似文献
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目的:观察穴位强化埋线疗法治疗慢传输型便秘的临床疗效和安全性。方法:依中央随机数字表,入选病例随机分为两组,即治疗组(104例)采用穴位强化埋线疗法,对照组(104例)采用口服麻仁软胶囊,观察两组临床疗效和相关指标症状积分、标志物残留情况,随访时间6个月。结果:治疗组临床总有效率优于对照组(P〈0.05)。治疗组各临床主要症状积分均比治疗前有统计学意义(P〈0.05),治疗组在治疗后的标志物残留数目较对照组明显减少(P〈0.05),治疗组标志物残留数目减少值明显优于对照组(P〈0.05)。结论:穴位强化埋线疗法依据相关中医外治法理论,结合现代操作手段,能明显改善便秘的临床症状,促进肠蠕动,是一种融多种疗法、多种效应于一体的方法,操作简单,痛苦小,具有很高的推广价值。 相似文献
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Exposure to ambient airborne particulate matter (PM) with an aerodynamic diameter less than 10 μm (PM10) links with public health hazards and increases risk for lung cancer and other diseases. Recent studies have suggested that oxidative stress is a key mechanism underlying the toxic effects of exposure to PM10. Several components of water‐soluble fraction of PM10 (sPM10) have been known to be capable of inducing oxidative stress in in vitro studies. In this study, we investigated if water‐insoluble fraction of PM10 (iPM10) could be also capable of inducing oxidative stress and oxidative damage. Human lung epithelial A549 cells were exposed to 10 μg/mL of sPM10, iPM10 or total PM10 (tPM10) preparation for 24 h. Here, we observed that all three PM10 preparations reduced cell viability and induced apoptotic cell death in A549 cells. We further found that, similar to the exposure to sPM10 and tPM10, the intracellular level of hydrogen peroxide (H2O2) in the iPM10‐exposed cells was increased significantly; meanwhile the activity of catalase was decreased significantly as compared with the unexposed control cells, resulting in significant DNA damage. Our data obtained from inductively coupled plasma‐mass spectrometry (ICP‐MS) assays showed that iron is the most abundant metal in all three PM10 preparations. Thus, we have demonstrated that, similar to sPM10, iPM10 is also capable of inducing oxidative stress by probably inducing generation of H2O2 and impairing enzymatic antioxidant defense, resulting in oxidative DNA damage and even apoptotic cell death through the iron‐catalyzed Fenton reaction. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 226–233, 2014. 相似文献
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目的:评价白内障超声乳化吸除联合双焦点Toric人工晶状体(IOL)植入术的散光矫正临床效果。方法:回顾性分析。纳入2020-08/2021-09间我院白内障超声乳化吸除联合双焦点Toric IOL治疗白内障合并角膜规则散光患者46例46眼的临床资料。术后随访3mo,评价术前及术后1、3mo裸眼远视力(UDVA)、裸眼近视力(UNVA)、矫正远视力(BCDVA)、矫正近视力(BCNVA)及散光的变化。测量并计算IOL轴位旋转度,行问卷调查在不同距离使用眼镜的必要性以及总体满意度。结果:术后1、3mo UDVA、BCDVA、UNVA、BCNVA与术前比较均有差异(均P<0.001),而术后1mo UDVA、BCDVA、UNVA、BCNVA与术后3mo比较均无差异(均P>0.0167)。术后3mo UDVA达到0.20(LogMAR)者46眼(100%),UNVA达到0.20(LogMAR)者40眼(87%)。散光矢量分析显示,术前角膜散光均值为1.88±0.70D,质心值为0.61D@177°±1.93D,术后3mo残余散光均值为0.33±0.30D,质心值为0.03D@34... 相似文献
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