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671.
672.
加拿大荷兰学院是一所服务地方经济的职业教育学院。分析其以专业为中心的教学团队建设的经验,国内高职高专院校可以得到启示,加以借鉴,建立以专业为中心的教师矩阵组织、配置专业协调员、促进专兼结合的双师型队伍建设及建立教师实践进修制度。 相似文献
673.
The aim of this study is to synthesize of magnetic SiO2 nanoparticles(MSNPs)loaded with Naproxen(NAP-MSNPs)for targeting anti-flammatory therapy.The Fe3O4 nanoparticles were coated with a thin layer of silica by stber method and the drug was encapsulated in it simultaneously.The optimal conditions were investigated for the synthesis of MSNPs.The shape,size,and phase structure of NAP-MSNP were characterized by transmission electron micrographs(TEM)and X-ray diffraction(XRD).The drug encapsulation efficiency was confirmed by FT-IR and measured by UV spectrometry.The NAP-MSNPs show the response at the external magnetic field and the drug could be released readily from NAP-MSNPs.All of these facts suggest the NAP-MSNPs could be applied in a promising drug release-controlling system for targeting anti-inflammatory therapy. 相似文献
674.
675.
《自然科学进展(英文版)》2020,30(5):697-706
Immunotherapy is an ascendant approach in cancer treatment. It shows more pronounced effects on killing cancer cells in a specific manner in particular against metastasis more than traditional techniques, such as chemotherapy or surgery. However, tumor immunosuppression limits the response of the immune system to cancer development. In this study, we developed a lipid-based nanocarrier doubly loaded with imiquimod (R837), a toll-like receptor 7 agonist, and caffeine, an adenosine receptor antagonist. This R837/caffeine loaded nanocarrier served as a nano-immunomodulator (RC-nIM) for combination treatment with radiotherapy (RT) against orthotopic breast cancer. RT-induced immunogenic cell death facilitated the production of tumor antigen and elicited the immune response in corporation with R837-medaited activation of antigen-presenting cells (APCs) while RC-nIMs being adopted. Additionally, caffeine, an adenosine analog, can successfully compete with adenosine in the tumor. The tumor-bearing mice that received RT together with RC-nIMs experienced the best antitumor effects and exhibited higher levels of T cells and APCs within the tumor; the growth of secondary tumors was also limited. This work serves as a proof-of-concept study for the development of a new immunotherapy strategy against cancer. 相似文献
676.
深空通信链路的特点(时延巨大、上下行链路非对称性、误码率、丢包率大和链路易中断)限制了采用地面文件传送协议在深空中的应用。借鉴信道编译码的思想,提出了适合深空环境的容失文件传递协议。采用容失文件传递协议,地面站只要接收到一定数量的数据包,满足解织条件就能够恢复原始信息,无需反馈确认信息。当通信距离较短时,文件传递时延受文件大小和传输速率变化的影响较大,而较长距离的传递时延主要由传播时延决定,其他因素影响有限。容失文件传递协议无需反馈确认、单向可靠传输,大大减少了文件传递时延、提高了系统的吞吐量也保证了通信系统的可靠性。 相似文献
677.
管道增输器的数值模拟与现场试验 总被引:1,自引:0,他引:1
理论分析和实验表明壁面振动能减小管道的摩擦阻力。文中对笔者发明和研制成功的管道增输器的工作原理、数值模拟和现场试验进行了介绍。现场试验表明:管道增输器不仅降低了管道摩擦阻力,而且能增大天然气管网的输气量。数值模拟也表明:在碰撞壁处产生的压力扰动波在诱发涡量脉动的同时,又与大结构涡环的径向分量对振荡腔的壁面发生作用,引起壁面振动,振荡腔是形成脉冲流的主要部件。 相似文献
678.
Lavelle EC 《Cellular and molecular life sciences : CMLS》2005,62(23):2750-2770
Vaccination is a highly effective means of disease prevention and has saved countless lives worldwide over the past 200 years.
Traditional vaccines based on killed and attenuated organisms and inactivated toxins have constituted the majority of clinically
used vaccines to date, but novel vaccines based on subunits of these organisms will be increasingly represented in future.
In contrast to attenuated and whole cell vaccines, subunit vaccines do not generally contain immune-stimulatory components
and are poorly immunogenic. As a result, new, potent and safe adjuvants and delivery systems are needed to enhance the immunogenicity
of these vaccines. Furthermore, there is a drive to replace injected vaccines with those that can be administered by mucosal
routes. Since the induction of innate immunity is crucial for vaccines to elicit potent antigen specific immune responses,
a greater understanding of innate immunity at mucosal surfaces and the mechanism of action of adjuvants and delivery systems
is required.
Received 28 June 2005; received after revision 2 August 2005; accepted 30 August 2005 相似文献
679.
许海燕 《海南大学学报(自然科学版)》1997,(3)
采用口服蓖麻油炒鸡蛋对210例晚期妊娠孕妇进行引产催产临床观察,并设300例为对照组,结果表明:蓖麻油炒鸡蛋组比对照组引产催产效果显著,引产有效率为76%,总产程平均为14小时5分;催产有效率为98.5%,总产程平均为5小时47分.而对照组引产有效率为60%,总产程平均为22小时20分;催产有效率为80%,总产程平均为10小时35分.新生儿窒息观察组比对照组少,两者差异有显著意义. 相似文献
680.
本文对具有双重喉管的双腔201 A3化油器腔体内流动进行了研究,首先用变分有限无法对腔内流动进行计算,给出了不同工况下阀门全开时化油器主油系的供油特性(包括沿程真空度分布曲线、化油器大喉管、小喉管边缘的真空度随进气流量的变化曲线)。然后对模型进行实验分析,与计算相比较,两者结果吻合较好。通过二元流与一元流计算的比较,揭示了有限元计算有助于化油器的节油和改善其气动性能。 相似文献