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41.
Glioblastoma multiforme (GBM) is the most common form of malignant glioma, characterized by genetic instability and unpredictable clinical behavior. GBM is marked by an extremely poor prognosis with median overall survival of 12~14 months. In this study, we detected the CD137L-expressing cells and IL-17-expressing cells in tumor tissues resected from patients with GBM. Expression of CD137L and IL-17 were assessed by immunohistochemistry, and the prognostic value of CD137L and IL-17 expression within the tumor tissues were assessed by Cox regression and Kaplan-Meier analysis. Immunohistochemical detection showed that positive cells of CD137L and IL-17 in glioblastoma tissue samples were 46.3% (19/ 41) and 73.2% (30/41) respectively. Expression of CD137L was not correlated with overall survival of GBM patients (P=0.594), while significantly longer survival rate was seen in patients with high expression of IL-17, compared to those with low expression of IL-17 (P=0.007). In addition, we also found that IL-17 expression was significantly correlated with Progression-free survival (PFS) (P=0.016) and death rate (P=0.01). Furthermore, multivariate Cox proportional hazard analyses revealed that IL-17 (P=0.018) and PFS (P=0.028) were independent factors affecting the overall survival probability. Kaplan-Meier analysis showed that PFS of high expression of IL-17 group were significantly longer (P=0.004) than low expression group with GBM. It is concluded that high levels of IL-17 expression in the tumor tissues may be a good prognostic marker for patients with GBM.  相似文献   
42.

Background

The mismatch of the elastic modulus between implants and bone tissue can lead to stress shielding, bone resorption and poor osseointegration. Compared with normal bone tissue, this problem is much more serious in osteoporosis. The purpose of this study was designed to find out whether the novel Ti-24Nb-4Zr-7.9Sn (TNZS) implant with low elastic modulus and high strength was suitable for biomedical material, especially in osteoporosis.

Methodology

In vitro study, the viability and Alkaline phosphatase (ALP) activity of osteoblasts on the TNZS and Ti-6V-4V (TAV) were observed. In vivo study, 30 adult female New Zealand rabbits were selected and divided randomly into two groups: sham-operation (SHAM, n = 6) and ovariectomised in combination with methylprednisolone treatment (OVX+MP, n = 24). Two implants were then placed in the tibia of each OVX + MP group rabbit, one in each side (left: TAV; right: TNZS). The OVX + MP group rabbits were sacrificed at 4 and 12 weeks after the implantation. The osteoporotic bone responses to the TNZS and TAV implants were evaluated by pull-out test, Micro-CT analyses and histological observation.

Principal Findings

Compared with the TAV group, the TNZS group showed a significant increase (P<0.05) in cell viability and ALP activity, new bone formation and pull-out force.

Conclusions

The novel TNZS implants show good biological performance both in vitro and in vivo, which suggests that the alloys are suitable for biomedical applications, especially in osteoporosis.  相似文献   
43.
基于研究生课程教学区别于本科教学的新高度、新要求和新期待,依托分子细胞生物学良好的理论教学基础,充分把握课程发展趋势,引导学生扩展知识外延并洞悉学科前沿,探索出将模块化教学设计与微课应用相结合的研究生课堂教学新模式。在分子细胞生物学的教学实践探索中,发现该模式对激发研究生学习兴趣、增进对知识的理解、培养学生的创新思维等方面均具有积极的作用。  相似文献   
44.
Slightly acidic electrolyzed water (SAEW) could promote the germination and growth of mungbean sprouts, and electron spin resonance analyses of SAEW showed that besides available chlorine, reactive oxygen species (ROS) existed in SAEW. Further research showed that, a series of antioxidant enzymes activity were also affected by SAEW. Lower superoxide dismutase activity and higher peroxidase, catalase and ascorbate peroxidase activity led to less hydrogen peroxide accumulated in mungbean sprouts treated by SAEW. Thus, the available chlorine and ROS present in the SAEW played a role in the mungbean sprouts’ antioxidant mechanism, which in turn appeared as a growth-promoting effect on the mungbean sprouts.  相似文献   
45.
Chronic inflammation contributes to many prevalent diseases worldwide, and it is widely accepted that inflammatory molecules contribute to DNA damage. In this ancillary study, we investigated the influence of an encapsulated fruit and vegetable juice powder concentrate on peripheral blood lymphocytes (PBL) DNA damage. Using a double-blind, placebo-controlled approach, subjects were randomly assigned capsules containing placebo, or one of two formulations of the juice powder. Blood was drawn at baseline and after 60 days of capsule consumption. We found DNA damage in isolated PBL is suppressed after consumption of the encapsulated juice powder, and damage was correlated with the level of systemic inflammation. These data suggest a potential health benefit by consuming the juice concentrate capsules through their ability to suppress DNA damage as measured in surrogate tissues (PBL).  相似文献   
46.
天门冬纳米制剂对小鼠抗氧化系统的影响   总被引:4,自引:0,他引:4  
目的:探讨中药天门冬及其纳米制剂对小鼠心肌线粒体中超氧化物歧化酶(SOD)活性,丙二醛(MDA)含量,肝组织中谷胱甘肽过氧化物酶(GSH-Px)活性的影响,观察纳米制剂能否更有效地改善机体的抗氧化能力.方法:采用D-半乳糖致衰老小鼠分别ig相同剂量的天门冬水提液及其纳米中药15 d,测定衰老小鼠心肌线粒体中SOD活性、MDA含量及肝组织中GSH-Px活性.结果:天门冬水提液及其纳米中药均能显著增强天门冬及其纳米中药均可提高小鼠心肌线粒体中SOD的活性(P<0.01),肝组织GSH-Px活性(P<0.01),降低心肌线粒体中MDA(P<0.05),且纳米中药的药效强于天门冬水提液的药效(P<0.01).结论:天门冬纳米制剂抗氧化能力优于天门冬超声波水提液.  相似文献   
47.
目的:探讨中药天门冬及其纳米化后对D-半乳糖衰老模型小鼠血清和肝的抗氧化作用.方法:采用D-半乳糖致衰老小鼠分别ig相同剂量的天门冬水提液及其纳米中药15 d,测定衰老小鼠血清中一氧化氮合酶(NOS)的活性,一氧化氮(NO)含量及肝组织中脂褐素(LP下)的含量.结果:天门冬水提波及其纳米中药均能显著增强小鼠血清中NOS的活性(P<0.01),提高N0含量(P<0.05),降低LPF含量(P<0.05),且纳米中药的药效强于天门冬水提液的药效(P<0.05).结论:天门冬水提液及其纳米中药均有抗氧化作用,且纳米中药比水提液药效更好.  相似文献   
48.
黑龙江省老鹳草属植物的资源调查   总被引:2,自引:0,他引:2  
目的:了解老鹳草属(Geranium)植物在黑龙江省的分布及其广布种居群所在的主要植物群落类型以及其单位面积蓄积量,为更科学合理地开发和可持续利用老鹳草提供资源学方面的依据.方法:查阅文献、腊叶标本和实地考察.结果:记录所调查的居群中老鹳草的生长环境及主要伴生植物并测量、计算单位面积蓄积量.结论:佳木斯地区地榆、蚊子草、杂类草草甸群落类型的鼠掌老鹤草单位面积蓄积量为73.57 kg/667.7 m2,凸脉苔草、榛子灌丛群落类型的粗根老鹳草单位面积蓄积量为18.24 kg/667.7 m2.  相似文献   
49.
Pleurotus ostreatus is widely cultivated worldwide, but the lack of an efficient transformation system regarding its use restricts its genetic research. The present study developed an improved and efficient Agrobacterium tumefaciens-mediated transformation method in P. ostreatus. Four parameters were optimized to obtain the most efficient transformation method. The strain LBA4404 was the most suitable for the transformation of P. ostreatus. A bacteria-to-protoplast ratio of 100:1, an acetosyringone (AS) concentration of 0.1 mM, and 18 h of co-culture showed the best transformation efficiency. The hygromycin B phosphotransferase gene (HPH) was used as the selective marker, and EGFP was used as the reporter gene in this study. Southern blot analysis combined with EGFP fluorescence assay showed positive results, and mitotic stability assay showed that more than 75% transformants were stable after five generations. These results showed that our transformation method is effective and stable and may facilitate future genetic studies in P. ostreatus.  相似文献   
50.
海水池塘中国对虾与罗非鱼施肥混养的实验研究   总被引:7,自引:0,他引:7  
利用 8个海水池塘陆基围隔 ,进行了封闭式施肥混养中国对虾与罗非鱼的实验研究 .结果表明 ,在对虾放养密度为 0 .92~ 2 .36尾·m- 2 的条件下 ,对虾成活率为 75.72~89.98% ,平均为 82 .40 % .产量在 1 1 .4~ 2 4 .1 g·m- 2 之间 (养殖期为 91d) .生产力为0 .2 39g·m- 2 .d- 1 .在罗非鱼放养量为 0 .2 4尾·m- 2 (体重 1 0 0 g左右 )的条件下 ,鱼虾的数量最适配比为 1 :1 0 ,中国对虾 (体长 3.0 0cm左右 )的最适放养量约为 2 .40尾·m- 2 .  相似文献   
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