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81.
脚压测量用传感器   总被引:1,自引:0,他引:1  
本文讨论了用于脚压测量的四类压力传感器,电阻式传感器、压电式传感器,光电式传感器,电容式传感器介绍了其结构、原理和特点,并分析了几种典型的测量接口电路。  相似文献   
82.
Fresh bone marrow from 43 cases of myeloma and three cases of plasma cell leukaemia has been phenotyped both by indirect immune-rosetting and, on fixed cytospin preparations, by indirect immunofluorescence. Both clustered and unclustered B cell associated antibodies from the IIIrd International Workshop on Human Leucocyte Differentiation Antigens were used. The results confirm the lack of many pan-B antigens on the surface of myeloma plasma cells, i.e. CD19-23, 37, 39, w40. Strong surface reactivity is seen with CD38 antibodies and with one CD24 antibody (HB8). Weak reactions are sometimes obtained with CD9, 10 and 45R. On cytospin preparations CD37, 39 and w40 are sometimes weakly positive, and anti-rough endoplasmic reticulum antibodies are always strongly positive. Specific and surface-reacting antiplasma cell antibodies are still lacking.  相似文献   
83.
Irradiated LCL cells from several sources activated the blood lymphocytes of a panel of donors. Individual differences were present but were small. Stimulated blood lymphocytes were more potent activators (after X-irradiation) than small lymphocytes in a one-way mixed lymphocyte reaction, indicating that the state of metabolic activity of the `stimulating' lymphocyte affects the level of activation achieved. However, LCL cells incubated for several days after irradiation had not lost stimulatory capacity. Lymphocytes of pigs, rabbits, rats and mice were much less responsive than human lymphocytes. The response of animal lymphocytes generally varied with the species of origin of the serum used in the cultures.  相似文献   
84.
85.
Two rare variants of HLA-A locus antigens, tentatively called HLA-A2K and HLA-A9HH, were serologically identified in the Japanese population. A2K and A9HH showed short reaction patterns of a series of anti-A2 and anti-A9 sera, respectively. The latter variant also reacted with some anti-A2 sera. Nucleotide sequences of full-length cDNAs for A2K and A9HH were determined. The results revealed that both antigens are encoded by previously undescribed alleles. The nucleotide sequence of the allele for A2K was identical to that of A*0207 except for a single nucleotide difference in exon 3. The nucleotide sequence of the allele for A9HH was identical to that of A*2402 except for two nucleotides in exon 2. These two nucleotides are shared by all the reported A2 alleles. These sequencing results the allele for A9HH were consistent with the serological cross-reactivity of A9HH with some anti-A2 sera.  相似文献   
86.
目的研究肺腺癌细胞生长环境及转移性与黏附分子CD44v6和CD29的表达关系。方法将起源相同、转移性不同的两个肺腺癌细胞系AGZY和Anip分别用简便肿瘤多细胞球体(MTS)培养法培养,并设常规单层贴壁细胞培养对照。通过倒置显微镜、扫描及透射电镜观察MTS形成情况,并用免疫组化法分别对MTS及贴壁细胞上CD44v6和CD29表达进行检测。结果MTS培养成功,贴壁细胞与MTS在细胞结构及细胞连接结构上相似,两种MTS在形态及结构上差异无显著性。免疫组化结果显示,CD29在高转移性的Anip细胞及其MTS上呈阳性表达;在低转移性的AGZY细胞及其MTS上阴性表达。CD44v6在Anip和AGZY细胞及MTS上均呈阳性表达,差异无显著性。贴壁细胞与MTS上两种黏附分子表达均无差异。结论成功建立了一种简易制备MTS的方法。细胞生长方式(单层贴壁与MTS)可能不影响CD44v6和CD29的表达。CD29表达可能与肺腺痛转移性相关;CD44v6表达可能与肺腺癌转移无关。  相似文献   
87.
88.
The response of human, rabbit and guinea-pig thymocytes in culture to blastogenic stimulants such as phytohaemagglutinin (PHA) and staphylococcal filtrate (SF) was usually considerably less than that seen with equivalent numbers of peripheral blood and lymph node lymphocytes.  相似文献   
89.
用EBV LMP2A重组痘苗病毒 (rVV LMP2A )转染人树突状细胞 (DC ) ,转染后的DC分别在第 1、 7、 14天刺激相同MHC背景的T细胞 ,在IL 2作用下诱导LMP2A特异性CTL。用LDH释放法检测CTL杀伤活性 ;流式细胞术 (FACS )检测CTL诱导分化过程中CD3+ 、CD4 + 、CD8+ 、CD5 6 + 等细胞的分群变化 ;RT PCR检测细胞分化过程中FasLmRNA表达 ;生物活性法检测功能性细胞因子IFN γ的分泌。结果显示本法诱导的CTL对靶细胞有特异性杀伤活性 ,第 2次和第 3次DC刺激后杀伤活性有所上升 ;在CTL诱导分化的第 7、 14、 2 1天细胞分群以CD4 + 、CD8+ 细胞为主 ;RT PCR证实所诱导的细胞内有FasLmRNA的表达 ;随细胞培养天数的增加IFN γ分泌增加 ,在第 14天达到较高水平。研究表明重组痘苗病毒载体rVV LMP2A转染的DC刺激T细胞可诱导出EBV LMP2A特异性CTL。  相似文献   
90.
BACKGROUND AND OBJECTIVES: The use of the manual hexadimethrine bromide (polybrene) test in routine cross-matching after accurately detecting cell grouping and irregular antibodies is prevalent in China. This article reports the importance of serum protein mediums in the performance of the manual hexadimethrine bromide test. MATERIALS AND METHODS: Blood group O red blood cells and Blood group AB and Rh positive serum were collected at random from healthy blood donators, IgG anti-D serum separated from pregnant woman, then tested with each other by the manual hexadimethrine bromide methods in routine tests and some designed corresponding tests with IgG, IgM anti-D monoclonal diagnostic reagents and some serum protein components. RESULTS: Red blood cells that were adjusted to 3-5% suspension by normal saline then only added in 0.7 ml low ionic medium (LIM) and two drops of polybrene solution adhere to the surface of test tubes' bottom when centrifuged, so it was difficult to perform the next approach, but the adherence disappeared when red blood cells' concentrations exceeded 20-30%. Rh positive red blood cells coated by anti-D have the same phenomenon. This adherence can be prevented by serum medium diluted from 1:128 to 1:1024 times by normal saline and hemoglobin medium diluted from 1:32 to 1:128 times, but not by albumin or immunoglobulin medium. The denary logarithm values of the greatest inhibited dilutions of serum and hemoglobin elution between antibody sensitizing red blood cells and the same pre-sensitizing red blood cells tests were no significant difference (P value > 0.05). CONCLUSIONS: The whole serum or serum protein mediums are important factors that can influence successfully performance of the manual hexadimethrine bromide test. So appliance of the manual hexadimethrine bromide test to immunohematology laboratory, such as when performing titrations of serum or plasma, or when testing eluates for antibody activity, this adherence must be considered.  相似文献   
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