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21.
以S.minnesota R595菌为免疫原,通过细胞融合获得8株分泌抗核心糖脂单抗的杂交瘤细胞系。对其中的两株代表性单抗2D6E7和3H4 2F7的血清学反应性以及在小鼠Hb/Mu腹腔感染模型中的保护作用进行了初步研究。菌体吸收试验和间接免疫荧光试验(ⅡF)表明,单抗能与多种革兰氏阴性杆菌(GNB)产生交叉反应,并且光滑型GNB的煮沸菌体荧光染色呈阳性,活菌染色呈阴性。保护性试验结果表明,3H4 2F7单抗能显著提高S.minnesota(野生菌株),鼠伤寒杆菌和E.Coli等光滑型GNB攻击的小鼠存活率(P<0.05),显示出抗核心糖脂单抗的良好交叉保护作用。若攻击前、后2h或攻击同时输入单抗3H4 2F7,对光滑型GNB的感染均有明显保护效果(P<0.05);2D6 E7单抗未表现有保护活性。  相似文献   
22.
为探讨职业性接触苯、甲苯、二甲苯对子代行为的影响,以46名父母生育期接触苯、甲苯、二甲苯的儿童为暴露组;抽取与暴露组同年龄、同性别、同班级、其父母无任何职业有害因素接触史的58名儿童为对照组,用WICS-R(韦克斯勒儿童智力量表)对研究对象进行智力测验,用NB-I型视运动反应仪测试视简单反应时。结果显示,接触组各智力测验的得分均低于对照组,视反应时指标慢于对照组,差异有显著意义;进一步的分层分析结果显示,母接触组的各项得分均低于对照组,而父接触组的各项得分与对照组之间差异无显著意义。  相似文献   
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Projection radiographic techniques have been used in a standardized manner for decades for the diagnosis of conditions of the foot and ankle; the indications for them and the pattern of findings useful in the initial diagnosis and monitoring of the course are generally known to clinical radiology staff. Computed tomography has been introduced as an extension of the basic procedures performed for diagnosis in the ankle and the hindfoot. In the case of complex fractures, however, specialist experience is essential. CT is an easily accessible investigative procedure and is meanwhile economical and very powerful. Magnetic resonance imaging supplements the range of investigations in special cases when there are particular problems. Microfractures, findings indicative of inflammation and/or dystrophy and, in particular questions concerning the musculoligamentous support system are the situations in which such investigations are needed. Ultrasound has an additive value vis-à-vis magnetic resonance imaging and is an easily accessible and highly effective examination procedure both for the primary diagnosis and for serial monitoring. Financial constraints in the healthcare sector are increasingly limiting purely medical indications. Regardless of this development, the retention of projection radiography, computer tomography, and magnetic resonance imaging must be demanded for the initial diagnosis in the care of foot and ankle injuries. The earliest possible implementation of all these techniques for the initial diagnosis is the first step towards effective treatment. Cafrefully chosen and, if appropriate, complementary strategies are needed for monitoring of the course and for assessment.  相似文献   
25.
本系统的107个电极中,103个分布于胸、背部,1个为参考电极,1个为V_3,其余用于肢导。本系统除能绘出2、4、8ms任意间隔的103通道同步的体表等电位图,常规12导联和V_(7 9)心电图,胸、背部位的心电图外,还可记录R峰值等电位图,∑R,Q波等电位图,nQ30、40,极大、极小轨迹图等。  相似文献   
26.
Summary 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) is a potent inducer of monocytic differentiation of the human promyelocytic leukemia cell line, HL-60. We have noted that 25-hydroxyvitamin D3 (25(OH)D3) in high doses is also capable of promoting monocytic differentiation of this cell line. To test the possibility that the latter activity is due to conversion of 25OHD3 to 1,25(OH)2D3 by HL-60, we exposed HL-60 cells to 25OHD3 and analyzed the products by HPLC and radioreceptor assay. When chromatographed in the traditional solvent system (isopropanol-hexane), a new peak appears which migrates with authentic 1,25(OH)2D3. However, in a solvent system containing dichloromethane, 90% of the peak migrates with another metabolite, 19-Nor-10-Keto-25OHD3 (19-Nor-25OHD3). Production of this metabolite is enhanced by living cells and is synthesized by both virgin HL-60 and those which have undergone differentiation. We next determined if authentic 19-Nor-25OHD3 also promotes differentiation of this cell. As assessed by appearance of the monocyte-specific surface antigen (63D3) and macrophage-specific esterase activity, we find that this metabolite does, in fact, induce monocytic differentiation of HL-60 with a potency of approximately 1/200 that of 1,25(OH)2D3 and similar to that of 25OHD3. In agreement with the effect upon cell maturation, 19-Nor-25OHD3 displaces3H-1,25(OH)2D3 from its HL-60 receptor with an efficiency comparable to 25OHD3. Hence, HL-60 cells convert 25OHD3 to 19-Nor-25OHD3, and 19-Nor-25OHD3 induces monocytic differentiation of HL-60 with comparable efficiency to its precursor, 25OHD3.  相似文献   
27.
Foropenseverewoundandthewoundafterdebridement,mostscholarsthinkthewoundshouldbeclosedindelayedfirst-phase.Meshrelaxingshortincision(MRSI)methodcanclosemoreskindeficiencyandhightensionopenwound,andavoidsubcutaneoushematomaandskinflapdrift.Intheexperiment,theexperimentalmodelonrattensionskinflaphasbeeninvolved,andthecontentofendothelin(ET)inratskinflaptissuehasbeenmeasuredinvariousperiodofwoundhealingaftermeshedrelaxingshortincisionsuturewithimmunohistochemistry,inordertodiscussprobablemechani…  相似文献   
28.
A large body of work relating to the occurrence of rickets in UK Asians is reviewed. Several theories of the aetiology of this condition are shown to be untenable: it is not exclusively a function of sunlight deprivation or of darker pigmentation; nor is it simply due to phytate-induced losses of calcium from the gut. Asian rickets, however, is associated with a high consumption of cereals, and experiments with rats have suggested a mechanism. In the absence of adequate vitamin D from sunlight, the low-calcium, high cereal intake of the UK Asian population may induce a state of mild secondary hyperparathyroidism which enhances the destruction of vitamin D and leads to a progressive reduction in vitamin D status and, ultimately, to the development of clinical rickets.  相似文献   
29.
以头孢呋辛钠为原料,从制备(R,S)-乙酸1-溴乙酯开始。经酯化反应的溶剂沉淀过程无须分离直接制得高纯度非晶型的头孢呋辛酯。本制备方法简便,适于工为化生产。  相似文献   
30.
R波相关振动法血压测量   总被引:1,自引:0,他引:1  
为了提高振地血压测量的准确性,提出了一咱基于心电R波与血压振动波之间相关性,识别振动信号的一种抗干扰方法=-R波相关法,结合振动波形特征识别,该方法可有效地提取信号,消除干扰影响,该算法已在16位8098单片机上实现,本文同时给出了程序的详细流程图。  相似文献   
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