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41.
42.
Linux系统移植主要包括bootloader的移植、内核移植、根文件系统的移植等三大部分。在基于Linux的嵌入式系统的构建过程中,根文件系统是不可缺少的重要组成部分。重点对利用busybox构建根文件系统的过程进行了详细的讲解,包括busybox的配置过程,根文件系统的构建过程,Web服务器BOA的构建过程,网络视频服务器MJPG-streamer的构建过程,NFS挂载根文件系统的测试过程,以及三种文件系统Cramfs、JFFS2及Ramdisk的制作过程,将几种不同的文件系统的性能进行了对比分析。实验表明制作完成的三种文件系统能够正常使用,并且运行稳定。  相似文献   
43.
通过人工繁殖,获得了两批大鲵的受精卵及其幼苗.利用组织学方法研究了大鲵的早期胚胎发育,并描述了其主要特征.同时,就此和其他两栖动物的胚胎发育进行了比较讨论,并指出了其共性与特殊性.  相似文献   
44.
Neural progenitor cells (NPs) have shown several promising benefits for the treatment of neurological disorders. To evaluate the therapeutic potential of human neural progenitor cells (hNPs) in amyotrophic lateral sclerosis (ALS), we transplanted hNPs or growth factor (GF)-expressing hNPs into the central nervous system (CNS) of mutant Cu/Zn superoxide dismutase (SOD1G93A) transgenic mice. The hNPs were engineered to express brain-derived neurotrophic factor (BDNF), insulin-like growth factor-1 (IGF-1), VEGF, neurotrophin-3 (NT-3), or glial cell-derived neurotrophic factor (GDNF), respectively, by adenoviral vector and GDNF by lentiviral vector before transplantation. Donor-derived cells engrafted and migrated into the spinal cord or brain of ALS mice and differentiated into neurons, oligodendrocytes, or glutamate transporter-1 (GLT1)-expressing astrocytes while some cells retained immature markers. Transplantation of GDNF- or IGF-1-expressing hNPs attenuated the loss of motor neurons and induced trophic changes in motor neurons of the spinal cord. However, improvement in motor performance and extension of lifespan were not observed in all hNP transplantation groups compared to vehicle-injected controls. Moreover, the lifespan of GDNF-expressing hNP recipient mice by lentiviral vector was shortened compared to controls, which was largely due to the decreased survival times of female animals. These results imply that although implanted hNPs differentiate into GLT1-expressing astrocytes and secrete GFs, which maintain dying motor neurons, inadequate trophic support could be harmful and there is sexual dimorphism in response to GDNF delivery in ALS mice. Therefore, additional therapeutic approaches may be required for full functional recovery.  相似文献   
45.
Pancreatic islet transplantation can correct the abnormal glucose metabolism of Type 1 diabetes. Although immunosuppressants greatly reduce the acute rejection rate in transplant patients, the long-term side effects can be debilitating. Therefore, researchers are seeking to develop new immunosuppressive regimens that induce maximal levels of immunosuppression with minor side effects. Rosmarinic acid (Ros A) is a secondary metabolite of certain herbs and has multiple biological activities, including anti-inflammatory effects. Here, we have investigated whether treatment of mice with a combination of Ros A and anti-CD154 monoclonal antibody (MR1) improves islet allograft survival in a murine model. After transplantation, the mice were treated with either Ros A, MR1, or both (the "double" treatment). Allograft survival was prolonged in the double-treated animals compared to animals that received only Ros A or MR1. As is the case with the single-treated animals at 15 days after transplantation, the double-treated recipients did not display a significant decrease in the expression of cytokines or the population of activated T cells. Infiltrating CD3(+) T cells were reduced in the MR1- or double therapy relative to control or RosA group. However, at the same time point, double-treated graft showed fewer apoptotic cells and increased expression of insulin and glucagons, compared to the single-treatment groups. Furthermore, long-term (>150 days) allografts that were received with double therapy exhibited larger islet clusters and contained more insulin- and glucagon-positive cells, relative to the MR1-treated grafts. In conclusion, treatment with both Ros A and MR1 has a synergistic effect in murine islet allotransplantation.  相似文献   
46.
In this paper, we present a metabonomic method for the investigation of abnormal metabolic process in both serum and liver tissue of liver transplanted rats. Syngeneic transplantation was performed on male Lewis rats. The serum and grafted liver on day 1, 3, and 7 post-transplant were collected to analyze endogenous metabolites using gas chromatography coupled with mass spectrometry (GC-MS). The method was validated with acceptable linearity, precision, and repeatability. Thirty-four metabolites in serum and 29 metabolites in liver were identified. Results of correlation analysis illustrated metabolites with similar function exhibited similar variations in liver and serum. The data processed by principle component analysis (PCA) showed time-dependent biochemical variations. As a consequence, the present study may offer specific putative pathways in the pathophysiological mechanism of orthotopic liver transplantation.  相似文献   
47.
为了更深入地研究土壤,以利于中药材栽培的地域选择,采用简便、快捷、分辨率高的FTIR技术,对53份土壤样品进行比较研究,结果表明,土壤样品在3 621,3 425,1 642,1 435,1 029,878,760和690cm-1有共有峰;但其相对强度有别,此外还有1 796,2 982和2 874 cm-1的峰也有所不同,借此可以客观地区分不同地域的土壤。试验同时说明甘肃天水、定西等地的土壤状况与山西土壤相近。土壤的FTIR指纹图谱可以为中药材的移栽提供极有价值的信息,同时也可以很好地用于土壤的研究。  相似文献   
48.
照相物镜移植应用的研究   总被引:2,自引:0,他引:2  
对于用逐步修改法设计光学系统,初始结构的选择是重要环节。除在典型形式中寻求初始结构外,也可以借鉴其它系统的光学结构进行相似创新。照相物镜移植应用指的是不同系统物镜因成像功能相似,故可实施光学结构的优化替代。本文研究了各种物镜成像功能的相似性,不同系统大孔径、大视场物镜光学特性的边缘性;根据像差理论阐明了照相物镜是大孔径、大视场系统理想的结构替代源;结合照相物镜丰富的光学结构资源的实际情况,指出移植应用是可行的。将照相物镜移植应用于其它系统大孔径、大视场物镜设计中,生产出与照相物镜结构相似、像质优良的镜头。实践证明了移植应用的实用性与可操作性。  相似文献   
49.
本文将卡特兰和大花惠兰的组织培养全过程,即培养基的筛选,培养条件,移栽方法,以及管理等进行了详细的介绍,为我省兰花的工业化生产,提供了可靠的依据。  相似文献   
50.
造血干细胞移植(HSCT)可用来治疗多种恶性造血系统疾病.HSCT成功植入的先决条件之一是必须输入足够量的造血干/祖细胞(HS/PCs).细胞剂量过少会导致植入时间延长,移植失败的可能性增大.从脐带血中直接分离的造血干细胞因数量较少而不能满足临床移植的需要.利用骨髓间充质干细胞作为滋养层联合细胞因子组合(SCF+G-CSF+TPO)使脐血造血干/祖细胞体外扩增75.2±15.0倍,CD34^+细胞扩增33.4±12.3倍.将扩增的细胞收集,重新悬浮于L-15培养液中制成造血干/祖细胞制剂,并在建立相应的检测技术基础上,进行了细胞制剂的无菌检测以及细胞制剂中细菌内毒素、牛血清残留量和干细胞因子残留量的检测.通过上述检测分析,为扩增的造血干/祖细胞制剂服务临床需要,辅助治疗恶性血液病和再生障碍性贫血以及遗传性贫血重建造血功能提供实验依据.  相似文献   
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