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51.

Objective  

To evaluate the predictive values of gene expressions of ribonucleotide reductase M1 (RRM1) and breast cancer susceptibility gene 1 (BRCA1) in peripheral blood from Chinese patients with non-small-cell lung cancer (NSCLC) treated with gemcitabine plus platinum.  相似文献   
52.
Radiation therapy has been widely applied in cancer treatment. However, it often causes thrombocytopenia (deficiency of white blood cells) as an adverse effect. Recombinant human interleukin-6 (rhIL-6) has been found to be a very effective way against this thrombocytopenia, but IL-6 has low stability in blood, which reduces its efficacy. To increases the stability and half-life of rhIL-6, it was modified by polyethylene glycol (PEG). The pharmacokinetics and the tissue distribution of PEG-rhIL-6 labeled with 125I were examined after subcutaneous injection in rats. The pharmacokinetic pattern of PEG-rhIL-6 was defined with linear-kinetics, and we fitted a one-compartment model with half-lives of 10.44–11.37 h (absorption, t 1/2K a) and 19.77–21.53 h (elimination, t 1/2Ke), and peak concentrations at 20.51–21.96 h (t peak) in rats. Half-lives and t peak of PEG-rhIL-6 were longer than those of rhIL-6 previously reported. In the present study, for deposition of PEG-rhIL-6 in rats, the tissue distribution examination showed that blood was the major organ involved, rather than liver. However, as to the elimination of PEG-rhIL-6, the major organ was the kidney. The excretion fraction of the injection dose recovered from urine was 23.32% at 192 h after subcutaneous administration. Less than 6% of PEG-rhIL-6 was eliminated via the feces at 192 h. These results indicate that PEG-rhIL-6 is a good candidate drug formulation for patients with cancer.  相似文献   
53.
Theaflavins (TFs) are the dimers of a couple of epimerized catechins, which are specially formed during black tea fermentation. To explore the differences among four main TF derivatives (theaflavin (TF1), theaflavin-3-gallate (TF2A), theaflavin-3′-gallate (TF2B), and theaflavin-3,3′-digallate (TF3)) in scavenging reactive oxygen species (ROS) in vitro, their properties of inhibiting superoxide, singlet oxygen, hydrogen peroxide, and the hydroxyl radical, and their effects on hydroxyl radical-induced DNA oxidative damage were systematically analyzed in the present study. The results show that, compared with (−)-epigallocatechin gallate (EGCG), TF derivatives were good antioxidants for scavenging ROS and preventing the hydroxyl radical-induced DNA damage in vitro. TF3 was the most positive in scavenging hydrogen peroxide and hydroxyl radical, and TF1 suppressed superoxide. Positive antioxidant capacities of TF2B on singlet oxygen, hydrogen peroxide, hydroxyl radical, and the hydroxyl radical-induced DNA damage in vitro were found. The differences between the antioxidant capacities of four main TF derivatives in relation to their chemical structures were also discussed. We suggest that these activity differences among TF derivatives would be beneficial to scavenge different ROS with therapeutic potential.  相似文献   
54.
Utilization of a two-line breeding system via photoperiod-thermo sensitive male sterility has a great potential for hybrid production in wheat (Triticum aestivum L.). 337S is a novel wheat male sterile line sensitive to both short daylength/low temperature and long daylength/high temperature. Five F2 populations derived from the crosses between 337S and five common wheat varieties were developed for genetic analysis. All F1’s were highly fertile while segregation occurred in the F2 populations with a ratio of 3 fertile:1 sterile under short daylength/low temperature. It is shown that male sterility in 337S was controlled by a single recessive gene, temporarily designated as wptms3. Bulked segregant analysis (BSA) coupled with simple sequence repeat (SSR) markers was applied to map the sterile gene using one mapping population. The wptms3 gene was mapped to chromosome arm 1BS and flanked by Xgwm413 and Xgwm182 at a genetic distance of 3.2 and 23.5 cM, respectively. The accuracy and efficiency of marker-assisted selection were evaluated and proved essential for identifying homozygous recessive male sterile genotypes of the wptms3 gene in F2 generation.  相似文献   
55.

Objective  

In this paper, we investigated the effect of the traditional Chinese medicine Chaiqin Chengqi Decoction (CQCQD) on serum cytokines in acute pancreatitis (AP) patients.  相似文献   
56.
越来越多的大众参与者通过互联网参加众包任务,他们之间形成了多种多样的关系。研究了猪八戒网站上大众参与者之间的竞争关系。通过分析大众参与者的加权竞争关系网络结构,发现他们之间的竞争程度并不十分激烈,但是不同技术类型用户之间的竞争程度有区别。之后以月份为时间尺度,分析猪八戒网站的核心用户在核心网络和边缘网络中的迁移行为。结果是大多数核心用户是比较稳定的,并且核心网络是典型的小世界网络。  相似文献   
57.
身体活动在个体发展各阶段具有广泛的心理健康效应。已有研究提示,有氧练习与抗阻练习对儿童、青少年的P3与工作记忆等认知表现具有积极影响,并且对学业成就测试有潜在积极效益。身体活动还对成年群体的执行功能及抑郁表现具有中等程度的改善效应,并且对罹患阿尔茨海默症及多发性硬化症老年群体的认知功能具有积极临床效果。身体活动心理效益的生物学机制主要体现在血液灌注水平提升、突触发生及脑源性营养因子的表达。未来研究中,应当丰富随机对照与纵向性质研究,身体活动与其它因素对脑功能影响的交互作用机制需要进一步了解。  相似文献   
58.
0引言
  2011年10月8日,为贯彻落实教育规划纲要,全面提高教师培养质量,推进教师教育课程改革,教育部颁布了《教师教育课程标准(试行)》。2012年2月10日,为了促进小学教师专业发展,建设高素质小学教师队伍,教育部制定了《小学教师专业标准(试行)》。以上两个文件(简称两个标准)的出台表明国家对小学教师培养工作的重视,教师教育工作重要性凸显。  相似文献   
59.
Many schools are beginning to implement multi-tier response to intervention (RTI) models for the prevention of reading difficulties and to assist in the identification of students with learning disabilities (LD). The present study was part of our larger ongoing longitudinal RTI investigation within the Florida Learning Disabilities Center grant. This study used a longitudinal correlational design, conducted in 7 ethnically and socio-economically diverse schools. We observed reading instruction in 20 classrooms, examined response rates to kindergarten Tier 1 instruction, and predicted students' first grade reading performance based upon kindergarten growth and end of year reading performance (n = 203). Teachers followed an explicit core reading program and overall, classroom instruction was rated as effective. Results indicate that controlling for students' end of kindergarten reading, their growth across kindergarten on a variety of language and literacy measures suppressed predictions of first grade performance. Specifically, the steeper the students' trajectory to a satisfactory outcome, the less likely they were to demonstrate good performance in first grade. Implications for future research and RTI implementation are discussed.  相似文献   
60.
Lin L  Gao Z  Wei H  Li H  Wang F  Lin JM 《Biomicrofluidics》2011,5(3):34112-3411210
This paper describes a simple method for fabricating a series of poly(ethylene glycol) diacrylate (PEG-DA) hydrogel microstructures inside microfluidic channels as probe for proteins and glucose. In order to demonstrate the feasibility of this newly developed system, bovine serum albumin (BSA) was chosen as a model protein. PEG microcolumns were used for the parallel detection of multiple components. Using tetrabromophenol blue (TBPB) and the horseradish peroxidase/glucose oxidase reaction system, bovine serum albumin (BSA) and glucose in human urine were detected by color changes. The color changes for BSA within a concentration range of 1-150 μM, and glucose within a range of 50 mM-2 M could be directly distinguished by eyes or precisely identified by optical microscope. To show the practicability of the gel particle array, protein and glucose concentrations of real human urine samples were determined, resulting in a good correlation with hospital analysis. Notably, only a 5 μL sample was needed for a parallel measurement of both analytes. Conveniently, no special readout equipment or power source was required during the diagnosis process, which is promising for an application in rapid point-of-care diagnosis.  相似文献   
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