Anaemia is a frequent problem after renal transplantation, whichmay appear as hypo-regenerative anaemia (due to myelotoxic drugsor infectious agents and/or poor graft function) or hyper-regenerativeanaemia (haemolysis or bleeding). It, therefore, seems reasonableto distinguish between different underlying causes of anaemiaaccording to reticulocyte counts. One of the presumably rather rare infectious agents causingtransient hypo-regenerative anaemia is the human parvovirusB19 (HPV B19) that was discovered in human blood 25 years ago[1] and was found to be the cause of ‘fifth disease’in children in the 1980s  相似文献   
22.
Use of commercially available cell culture inserts for primary culture and electrophysiologic studies of guinea pig gastric mucous epithelial cells     
Michael J. Rutten 《Methods in Cell Science》1992,14(4):235-245
Summary The adherence, growth, and electrophysiologic properties of guinea pig gastric mucous epithelial cells were investigated using porous membrane filters. We also tested three commercially available Ussing-type chambers that were designed to be used with the various porous membrane supports. Overall, the 0.45-µm Falcon-Cyclopore porous membrane was found to be very favorable for the consistent attachment and growth of our cells. This same filter also gave good results in the detection of periodic acid Schiff-positive mucous glycoprotein and Nile red neutral lipid fluorescence in the gastric mucous cells. Our cells grew poorly on collagen-coated Costar-Snapwells and Millipore Millicell-CM porous filters. For measurement of transepithelial potential difference resistance, and short-circuit current, the Costar-Snapwell with the Costar-Snapwell Diffusion-chamber system was superior in design and operation when compared to the Costar Transwell-COL, Falcon-Cyclopore, or Anotec-Anocell porous inserts used with conventional Ussing-chambers. The gastric mucous cells grew best on ICN-Cellagen membranes, but these filters routinely detached from their plastic holder and therefore could not be used for Ussing-chamber studies. The large 24.5-mm, 0.40-µm pore size Costar-Transwell-COL and the 24.1-mm, 0.45-µm Falcon-Cyclopore membranes gave good results when used in a modified horizontal-chamber for microelectrode analysis of membrane potentials and resistances of the gastric mucous cell monolayers.  相似文献   
23.
Lead poisoning in precious metals refinery assayers: A failure to notify workers at high risk     
David G. Kern 《American journal of industrial medicine》1994,25(5):759-767
Lead poisoning in a precious metals refinery fire assayer and a routine OSHA inspection prompted an investigation of the index facility, a survey of the industry, and efforts to notify assayers of this previously unrecognized hazard. Air and blood samples were obtained at the index facility. Management personnel from all fire assay laboratories in Rhode Island and southern Massachusetts were interviewed. The industry's trade association, OSHA, NIOSH, trade unions, and the media were asked to assist in a nationwide notification effort. Assayers at the index facility had excessive exposures to lead due to an age-old, lead-based assaying method that remains the industry gold standard. Blood lead levels of the three assayers (mean 61.3 μ/dl, range 48–86 μg/dl) were considerably higher than those of 16 other refinery workers (mean 27.4 μg/dl, range 13–49 μg/dl). The industry survey revealed inadequate knowledge of both the lead hazard and the applicability of the OSHA lead standard. Notification efforts failed in large part due to economic obstacles. The notification of workers at high risk of lead exposure and the eradication of occupational lead poisoning will require greater attention to economic forces. © 1994 Wiley-Liss, Inc.  相似文献   
24.
老年患者不同证型红外热象舌图温度负荷的变化   总被引:1,自引:0,他引:1  
刘黎青  周盛年  张亚伦 《山东中医药大学学报》2003,27(1):34-36
目的 :探讨老年不同中医辨证分型的红外热象舌图温度负荷变化。方法 :被测试者分为阴虚证、阳虚证、气滞血瘀证、气血两虚证、湿热证五组。施以冷负荷后 ,红外舌图分析选取七个点温为代表 ,以计算机图像处理系统确定纵横坐标位置 ,对采录的所有红外舌图进行分析、处理。结果 :阴虚组舌尖、舌前两侧点冷负荷前后变化值与正常组比较 P<0 .0 5 ;阳虚组各点冷负荷前后变化值均低于正常组 (除 M点 ) ,且 T点、TL 点、TR点、M点均大于气血两虚组及湿热组 P<0 .0 5 ;气滞血瘀组舌温变化值低于正常 (T点 P<0 .0 5 ) ;气血两虚组各点温变化值均显著低于正常组 (P<0 .0 5~ 0 .0 1)及其他证型组 ;湿热组舌尖、舌前两侧点冷负荷前后变化值与正常组比较 P<0 .0 5 ,且低于阴虚组、阳虚组、气滞血瘀组。结论 :老年不同中医辨证分型的红外热象舌图各有其特征 ,红外热象舌图直观、重复性强 ,可作为中医辨证分型和疗效判断的临床指标  相似文献   
25.
红细胞膜通道力学效应的探讨   总被引:1,自引:0,他引:1  
萧天庆 《中国生物医学工程学报》1992,11(3):150-156
在考察红细胞双凹碟形体形成的基础上,讨论了红细胞的输氧功能与红细胞变形的关系,揭示了红细胞膜通道的力学效应:当红细胞呈双凹碟形时,PiPo的地方,红细胞膜通道有释放出氧的现象,其氧的总流率为 J=Lo_2(Pio_2-Poo_2) Lp(Pi-Po) 式中Lo_2为O_2分压差引起的膜通道对氧的流导,PiO_2、Poo_2为膜内外的氧分压;Lp为由于压差引起的膜通道对氧的流导。  相似文献   
26.
获得性纯红再障患者外周血T细胞亚群分析   总被引:7,自引:0,他引:7  
代阳  刘霆  朱焕玲  崔旭  徐才刚  毛咏秋 《四川医学》2004,25(3):257-259
目的 本研究通过分析获得性纯红再障患者外周血T细胞亚群 ,进一步探讨该病的细胞免疫发病机制。方法 用抗人CD3、CD4、CD8、IFN γ及IL 4单抗结合人外周血单个核细胞 ,流式细胞术分析单个核细胞中CD3 +、CD4+、CD8+细胞数Th1、Th2、Tc1、Tc2细胞数以及CD4+/CD8+、Th1/Th2、Tc1/Tc2比值。结果 贫血组患者 ,外周血CD3 +细胞和CD8+细胞明显增加 (P <0 .0 1) ,CD4+/CD8+比例倒置 (P <0 .0 5 ) ;Tc2细胞明显增加 (P <0 .0 5 ) ,Tc1/Tc2比值降低(P <0 .0 5 ) ,治疗后血象恢复的患者各增高的亚群细胞均有所恢复 ,接近正常。结论 在获得性纯红再障患者T细胞明显增高 ,其中主要是CD8+细胞 ,而在CD8+细胞中 ,是Tc2细胞发挥了重要作用。经治疗有效的患者 ,其增高的T细胞亚群降低 ,提示以纠正病人细胞免疫异常为主的治疗方案有益于获得性纯红再障的治疗。  相似文献   
27.
A role for lasers in the treatment of pigmented skin grafts     
C. Raine  K. Al-Nakib  A. A. Quaba 《Burns : journal of the International Society for Burn Injuries》1997,23(7-8):641-644
The development of aberrant pigmentation represents an unwelcome complication to an otherwise successful split skin graft resulting in a loss of colour match and, so it follows, of cosmesis. We present two cases where lasers have been successful in the treatment of this problem.  相似文献   
28.
Indirect detection of anti-acetylcholinesterase compounds in microcolumn liquid chromatography using packed bed reactor with immobilized human red blood cell acetylcholinesterase and choline oxidase     
Jaroslav S alamoun  Jo rg Remien 《Journal of pharmaceutical and biomedical analysis》1992,10(10-12):931-936
The inhibiting compounds were separated by micro-column liquid chromatography in the mobile phase containing the natural substrate acetylcholine. A home-made packed bed microbioreactor system containing immobilized enzyme acetylcholinesterase (ACHE) in human red blood cell membrane and choline oxidase (CHO) from alcaligenes was used for the post-column conversion of acetylcholine to hydrogen peroxide which was detected by an electrochemical detector. The inhibition effect of the solutes caused a decrease in the acetylcholinesterase activity, a decrease in the formation of hydrogen peroxide and also a decrease in the response corresponding to the concentration of the solutes. The rate of the enzyme regeneration was also recorded. The micro-system was compared with a conventional LC system comprising commercially prepared enzyme reactor. The stability of the enzymes is at least 3 weeks at ambient temperature. The limit of detection depends on biological activity of inhibition and for galanthamine was 1 pmol.  相似文献   
29.
荔枝壳红色素的提取及稳定性观察   总被引:4,自引:0,他引:4  
何战胜  李贵荣  刘传湘 《南华大学学报(医学版)》2002,30(3):269-271
以荔枝壳为原料,在酸性条件下浸提荔枝壳红色素,并对其稳定性进行了研究,结果表明,该色素在酸性条件下对光、热、常用食品添加剂均具有较好的稳定性。  相似文献   
30.
母血中胎儿有核红细胞的荧光原位杂交法在产前诊断中的可行性探讨     
徐可树  朱剑文  潘群  邹丽 《华中科技大学学报(医学版)》2002,31(6):675-676,679
探讨荧光原位杂交法(FISH)对母血中胎儿有核红细胞(NRBC)进行无创性产前诊断的可行性。20例孕龄15-20周的孕妇外周血经不连续密度梯度离心、制片、显微镜下识别并共计数NRBC及定位,然后行Y染色体的FISH检测。结果发现10例孕男性胎儿的孕妇外周血细胞涂片中每例均有阳性杂交信号出现;阳性率为60%(24/40)。10例孕女性胎儿的孕妇外周血细胞涂片中1例出现阳性杂交信号;阴性率为95%(38/40),假阳性率仅为5%(2/40)。结果提示FISH法对于用母血中分离到的胎儿细胞进行染色体异常的无创性产前遗传学检查具有重要意义。  相似文献   
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21.
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