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141.
钱怀洲 《顺德职业技术学院学报》2010,8(2):7-9
对两种不同的二氧化碳双级压缩低温制冷循环进行了分析.得到在一定的蒸发温度和冷却器出口温度下.一次节流不完全中间冷却二氧化碳双级压缩循环COP较大、最优冷却压力较低、具有良好的发展前景。 相似文献
142.
应用远程无线信息传输技术,可以实现对终端的快捷、有效管理。为了设计一个结构清晰、扩展性强、易于开发和维护的系统,提出了采用J2EE中的struts技术并结合MVC的设计模型来构建系统的解决方案,详细分析了系统的框架模型、功能模块、层次结构以及具体实现流程。 相似文献
143.
目的:探讨食管鳞状细胞癌组织中淋巴管生成的临床病理意义.方法:应用单克隆抗体D2-40检测食管癌周围和中心区以及正常食管组织中微淋巴管密度(lymphatic micro vessel density,LMVD),分析其与食管癌患者年龄、性别、食管癌分化程度、淋巴结转移的关系.结果:肿瘤周围区LMVD明显高于中心区和正常组织.肿瘤周围区LMVD和淋巴结转移密切相关,而与肿瘤的分化程度无关.结论:食管癌在肿瘤周围区存在着明显的淋巴管形成,检测肿瘤周围淋巴管密度可以预测肿瘤淋巴结转移,因此具有良好的临床病理应用价值. 相似文献
144.
沈国丰 《湖州职业技术学院学报》2010,8(4):28-30
高校二级学院校园文化品牌建设,对于增强学院内部的凝聚力,实现学院的发展具有重要的意义。二级学院校园文化品牌建设的原则应体现大学精神,体现专业特色,体现传承和发展。而具体建设的途径则应包括提升品牌的价值、丰富品牌的精神内涵、加大品牌的培育力度、重视品牌的仪式功能与意义等。 相似文献
145.
Zhao-liang Xin Xiao-kang Wu Jian-rong Xu Xi Li 《Journal of Zhejiang University. Science. B》2010,11(7):516-523
Objective: To assess if arachnoid cells have the capability to present antigen and activate T-lymphocytes after stimulation by bloody cerebrospinal fluid (CSF), and to illuminate the mechanism of coagulation-initiated inflammation in the subarachnoid space after subarachnoid hemorrhage (SAH). Methods: Arachnoid cells were cultured, characterized, and examined by immunofluorescence for the basal expression of human leukocyte antigen-DR (HLA-DR). Expression of HLA-DR, after co-culturing arachnoid cells in vitro with bloody CSF, was investigated by immunofluorescence and flow cytometry (FCM). The variation of arachnoid cells' ultrastructure was observed by transmission electron microscope (TEM). Arachnoid cells were co-cultured with peripheral blood mononuclear cells (PBMCs). The content of soluble interleukin-2 receptor (sIL-2r) in culture medium was detected by enzyme-linked immunosorbent assay (ELISA). Results: (1) Arachnoid cells were successfully cultured for many passages. The immunofluorescent staining was positive for HLA-DR in over 95% of the human arachnoid cells. The punctate HLA-DR was distributed in cytoplasm and not in the karyon. (2) After co-culturing arachnoid cells in vitro with bloody CSF, numerous particles with strong fluorescence appeared in the cytoplasm on Day 6. On Day 8, the quantity of particles and fluorescent intensity were maximal. FCM showed that the percentage of HLA-DR expressing cells was (2.5±0.4)% at the first 5 d, increasing to (60.8±3.6)% on Day 7. (3) After co-culturing arachnoid cells in vitro with bloody CSF, many lysosome and secondary lysosome particles were present in the cytoplasm. Hyperplasia of rough endoplasmic reticulum and enlarged cysts were observed, with numerous phagocytizing vesicles also observed at the edge of the arachnoid cells. (4) Arachnoid cells stimulated by bloody CSF were co-cultured in vitro with PBMCs. The content of sIL-2r in the culture medium, having been maintained at around 1.30 ng/ml during the first 3 d, had increased by Day 4. The content of sIL-2r peaked 7.53 ng/ml on Day 7 and then reduced gradually. Conclusions: (1) Basic HLA-DR expression is present in arachnoid cells. (2) After stimulation by bloody CSF, arachnoid cells have the potential to serve as antigen presenting cells (APCs) and the ability to activate T-lymphocytes, indicating that arachnoid cells are involved in the mechanism of coagulation-initiated inflammation in the subarachnoid space after SAH. 相似文献
146.
姚昱旻 《湖南广播电视大学学报》2006,(3):91-92,88
JXTA平台是P2P技术的进一步发展,它给开发人员提供了一套统一的灵活的标准协议和类库。使用JX-TA平台,开发人员可以从具体的P2P技术底层细节中解脱出来,从而更加专注于应用程序的功能实现。 相似文献
147.
以乳酸为原料、辛酸亚锡为催化剂制备聚乳酸(PLA);以PI。A、Sm、钛酸四正丁酯(TBT)为原料,采用溶胶凝胶法制备稀土Sm掺杂PLA/TiO2有机无机杂化材料。XPS分析结果显示了Sm的加入。动态凝血时间测定法测定结果表明。Sm的掺杂提高了PLA/TiO2的抗凝血能力,并且在加入量为wt0.6%时效果最佳。 相似文献
148.
149.
Muriel Meunier 《Economics of Education Review》2011,30(1):16-38
This paper investigates empirically whether immigrant students in Switzerland perform poorly compared to their native counterparts and provides some explanations. Using a national sample of the 2000 PISA (Programme for International Student Assessment) database, we first analyze the impact of immigrant status on pupils’ achievement. We find a negative and significant impact of immigrant status on test scores in reading, mathematics and science literacy, even after controlling for a set of characteristics. We then decompose the observed reading score gap between Swiss and immigrant students to identify whether gaps in endowments explain test score differences along the distribution. Lower endowments explain most of the achievement gap in reading between Swiss and second-generation immigrants. However, lower returns explain around one quarter of the achievement gap between Swiss and first-generation immigrants for the weakest pupils. 相似文献
150.