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71.
A 63-year-old man developed paraparesis and signs of meningeal irritation 4 days after a fall which caused a minor contusion of the cervical spine. Magnetic resonance imaging (MRI) revealed an extensive spinal subdural hematoma. The usefulness of MRI for diagnosis and successful conservative treatment is discussed.  相似文献   
72.
提高矿井通风系统的安全和可靠性   总被引:3,自引:0,他引:3  
分析了矿井通风系统存在的问题 ,针对性地提出了一些提高矿井通风系统安全及可靠性的措施  相似文献   
73.
74.
康睿  冯汉夫  申宏  何虎 《西北水电》2007,(1):70-72,78
在DDE动态数据交换基础上,采用本地以太网UDP用户数据报协议,解决了组态王不支持网络变量从本机输出的问题,完善了系统功能。  相似文献   
75.
光纤光栅最佳切趾函数的研究   总被引:6,自引:2,他引:4  
黄雯  韩一石等 《光电子.激光》2002,13(12):1247-1251
采用耦合模理论,给出了用传输矩阵法计算光纤Bragg光栅(FBG)特性的方法,进而得到了在不同切趾函数形式下的FBG反射谱的数值解。通过理论分析,给出了最佳切趾函数反射谱和群时延特性曲线。  相似文献   
76.
介绍了国产新型催化剂惭二醇锑在洛阳石油化工总厂聚酯装置上的使用情况,结果表明:乙二醇锑催化剂活性高、易溶解;以乙二醇锑催化剂合成的聚酯产品质量稳定,纺丝时的加工性能明显得到改善。  相似文献   
77.
水资源的合理开发、利用及保护已成为人类社会持续发展的一项重要课题。我们要十分注意珍惜水、保护水,合理的开发利用水,使有限的水资源得到有效利用。  相似文献   
78.
Murine collagen-induced arthritis (CIA) is known as a T cell-mediated autoimmune disease, although autoantibodies are also suspected to be associated with the onset of the disease. To determine the origin of such T cells in the joints of mice with CIA, their phenotypic properties as well as those of T cells in other immune organs were examined in DBA/1 mice. Since a significant number of mononuclear cells (MNC) was also yielded by the joints of normal DBA/1 mice, the properties of these T cells were examined in parallel. When CIA was induced by an intradermal injection of type II collagen at the base of the tail, the numbers of MNC yielded by the regional lymph nodes and the foot joints were doubled. Interestingly, regardless of the onset of CIA, the joints were always comprised of unique T cell populations, including IL-2(R)alpha- beta+ T cells, gammadelta T cells, CD8alpha+ beta- cells, and CD44+ L-selectin- cells. All these properties coincide with those of extrathymic T cells in liver and intestine. In the case of gammadelta T cells in joints, Vgamma and Vdelta usages were unique and different from those in the other organs. More importantly, Vgamma and Vdelta usages in gammadelta T cells in the joints of normal mice and in those of mice with CIA were essentially the same. Taken together with the expression of recombination-activating gene-1 and -2 mRNAs by MNC in mice with CIA, these findings raise the possibility that the joints have their own resident T cells that are extrathymically generated in situ.  相似文献   
79.
Recombinant adeno-associated virus 2 (AAV) virions were constructed containing a gene for resistance to neomycin (neoR), under the control of either the herpesvirus thymidine kinase (TK) gene promoter (vTK-Neo), or the human parvovirus B19 p6 promoter (vB19-Neo), as well as those containing an upstream erythroid cell-specific enhancer (HS-2) from the locus control region of the human beta-globin gene cluster (vHS2-TK-Neo; vHS2-B19-Neo). These recombinant virions were used to infect either low density or highly enriched populations of CD34+ cells isolated from human umbilical cord blood. In clonogenic assays initiated with cells infected with the different recombinant AAV-Neo virions, equivalent high frequency transduction of the neoR gene into slow-cycling multipotential, erythroid, and granulocyte/macrophage (GM) progenitor cells, including those with high proliferative potential, was obtained without prestimulation with growth factors, indicating that these immature and mature hematopoietic progenitor cells were susceptible to infection by the recombinant AAV virions. Successful transduction did not require and was not enhanced by prestimulation of these cell populations with cytokines. The functional activity of the transduced neo gene was evident by the development of resistance to the drug G418, a neomycin analogue. Individual high and low proliferative colony-forming unit (CFU)-GM, burst-forming unit-erythroid, and CFU-granulocyte erythroid macrophage megakaryocyte colonies from mock-infected, or the recombinant virus-infected cultures were subjected to polymerase chain reaction analysis using a neo-specific synthetic oligonucleotide primer pair. A 276-bp DNA fragment that hybridized with a neo-specific DNA probe on Southern blots was only detected in those colonies cloned from the recombinant virus-infected cells, indicating stable integration of the transduced neo gene. These studies suggest that parvovirus-based vectors may prove to be a useful alternative to the more commonly used retroviral vectors for high efficiency gene transfer into slow or noncycling primitive hematopoietic progenitor cells, without the need for growth factor stimulation, which could potentially lead to differentiation of these cells before transplantation.  相似文献   
80.
We describe the case of a young woman with pain on turning her head attributable to a malformation of the hyoid bone. Diagnosis was established using spiral computed tomography with the patient's neck in the position of greatest discomfort and with 3-dimensional reconstruction of the hyoid bone. Prior conventional radiography and magnetic resonance imaging did not aid in finding a diagnosis. After surgical removal of both greater cornua of the hyoid bone there was a complete relief of symptoms.  相似文献   
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