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51.
Lu  YQ; Nichols  ME; Bigbee  WL; Nagel  RL; Blumenfeld  OO 《Blood》1987,69(2):618-624
We have explored the polymorphism of the glycophorin system in the human erythrocyte membrane using the immunoblotting techniques and examining 52 individuals selected without prior bias as to their serologic state and ten documented serologic variants of M, N, S, s blood group system. Polyclonal antisera to alpha glycophorin and to alpha glycophorin CNBr carboxyl terminal fragment C (residues 82-131) and M and N specific monoclonal antibodies (MoAbs) were used. The first two reagents detect specific regions of the alpha glycophorin molecule and all electrophoretically resolved species of glycophorins immunologically related to alpha and delta glycophorins (delta glycophorin, [alpha-delta] hybrids and other glycophorins with an alteration in the carboxyl terminal segment); the M and N MoAbs identified the glycophorin species containing or lacking the M or N determinant in the amino terminal octapeptide structures. We find that immunoblotting confirmed in all cases the serologically determined phenotype; we also find that polymorphic forms of the glycophorin system are relatively infrequent; immunoblotting, independent from serologic testing, was capable of detecting five mutants, two most likely S-s-U-phenotypes; a new glycophorin species was detected in normal red cells with both antiglycophorin and antipeptide C sera, which is not evident with MoAbs; immunoblots of known glycophorin variants (En(a-), U-, Mg, Mi I, II, III, V, and Sta) confirmed but also extended our knowledge of the abnormal glycophorins involved; and the He+ and Wrb(-) cells showed normal patterns.  相似文献   
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目的:考察离子导入和电穿孔对双氯芬酸钠经皮渗透的影响。方法:采用双室扩散池和SD大鼠皮、进行双氯芬酸钠饱和水溶液经皮被动扩散、离子导入(0.5mA/cm^2)和电穿孔导入(130V,740ms或100ms,200个脉冲,方波,占空比1:1)的 研究。结果:电穿孔和离子导入均能显著促进双氯芬酸钠的经皮渗透,其增渗倍数分别为25.1和7.5。延长脉冲7时间将改善电穿孔的促渗效果,初步研究表明本实验条件的电穿孔及离子导入未引起皮肤的损伤。结论:电穿孔技术可用于促进小分子解离型药物的经皮渗透。  相似文献   
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The clinical significance of interleukin 2 receptor (IL2R) concentrations in serum was determined for 344 children with newly diagnosed acute lymphoblastic leukemia (ALL). Serum levels of IL2R in patients (267 to 80,000 U/mL, median 2,007 U/mL) were significantly higher than normal control values (170 to 738 U/mL, median 347 U/mL) (P less than .0001). Measurements in cases of T cell ALL were lower than in the non-T, non-B cases (P = .02). Among the 264 patients with non-T, non-B ALL, but not in those with T cell disease, higher serum IL2R levels (greater than 2,000 U/mL) were associated with a poorer treatment outcome (P = .04). In a multivariate analysis, serum IL2R level contributed independent prognostic information beyond that conveyed by leukocyte count, race, and age (P = .04). One explanation for these results is that soluble IL2R competes with normal lymphocyte- integrated IL2R for the ligand and thus could suppress host antitumor immunity.  相似文献   
56.
Hirsch  JI; Banks  WL  Jr; Sullivan  JS; Horsley  JS  d 《Radiology》1989,171(1):109-110
Because a 1% sterile solution of methylene blue used for occult breast tumor localization has been shown to interfere with the estrogen-receptor protein (ERP) binding-capacity assay, isosulfan blue in a 1% injection was studied as a potential alternate stain. Cytosols derived from ERP-positive lyophilized powders and human breast tissue were evaluated with and without varying levels of treatment with isosulfan blue. No modification of the ERP-specific binding capacity was found with this stain. The use of isosulfan blue for localization of occult breast tumor is suggested when an ERP binding capacity assay is anticipated.  相似文献   
57.
Lethal neonatal Menkes' disease with severe vasculopathy and fractures   总被引:1,自引:0,他引:1  
A male neonate presented with an acute onset of severe intra-abdominal bleeding, haemorrhagic shock and multiple fractures leading to death on d 27. Menkes' disease was diagnosed at autopsy and confirmed by copper accumulation studies on cultured fibroblasts. Such an early onset of fatal complications in this condition has not been previously reported. New insights into the pathogenesis of Menkes' disease provided by DNA mutation analysis and difficulties in neonatal diagnosis are discussed. Menkes' disease should be considered in male infants with pathological fractures and other signs of connective tissue disease, even in the neonatal period.  相似文献   
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目的:就成体干细胞移植治疗脑梗死的研究进展进行综述。资料来源:应用计算机检索Medline 1995-01/2006-12和highware 1995-01/2006-12期间干细胞移植和脑梗死关系的文献,检索词“stem cell,transplantation,stroke,therapy”,并限定文章语言种类为英文。同时检索CBMdisc、维普数据库1998-01/2006-05期间的相关文献,限定文章语言种类为中文,检索词“干细胞,移植,脑梗死治疗”。资料选择:选取干细胞移植和脑梗死关系的文献进行初审,删除胚胎干细胞和与脑梗死无关的的文章,然后查找余下文献的全文。资料提炼:共检索50篇干细胞移植与脑梗死的相关文献,其中30篇符合要求。排除的20篇中,15篇属于胚胎干细胞研究的内容,5篇属于重复的研究。资料综合:成体干细胞移植治疗脑梗死是一种新的治疗方法,初步的动物研究证明它能改善神经功能缺失症状。但还存在一些问题,如成体干细胞移植的存活时间、安全性、体外培养的最适条件等。其作用机制也有待进一步深入研究。总的来说,成体干细胞来源充足,容易获取,可通过体外培养扩增,可静脉注射,从而避免侵入性的操作即可到达损伤脑的局部,利用自身的成体干细胞进行移植还可以避免移植物抗宿主反应,因此作为“种子”细胞优于的胚胎干细胞,不存在伦理的问题。结论:成体干细胞移植治疗脑梗死还存在一些问题,其作用机制也有待进一步深入研究,其作为“种子”细胞优于胚胎干细胞,不存在伦理的问题,具有广阔的临床应用前景。  相似文献   
60.
We studied the value of leukocyte depletion of platelet transfusions for the prevention of secondary human leukocyte antigen (HLA)- alloimmunization in patients with a high-risk of prior immunization induced by pregnancies. Seventy-five female patients with hematologic malignancies (mostly acute leukemia) and a history of pregnancy were randomized to receive either standard random single-donor platelet transfusions (mean leukocytes, 430 x 10(6) per transfusion) or leukocyte-depleted random single-donor platelet transfusions. Leukocyte depletion to less than 5 x 10(6) leukocytes per platelet transfusion (mean leukocytes, 2 x 10(6) per transfusion) was achieved by filtration. Of the 62 evaluable patients, refractoriness to random donor platelets occurred in 41% (14 of 34) of the patients in the standard group and in 29% (8 of 28) of the patients in the filtered group (P = .52); anti-HLA antibodies developed in 43% (9 of 21) of individuals in the standard group and 44% (11 of 25) of cases in the filtered group. The time toward refractoriness and development of anti- HLA antibodies was similar for both groups. We conclude that leukocyte depletion of random single-donor platelet products to less than 5 x 10(6) per transfusion does not reduce the incidence of refractoriness to random donor platelet transfusion because of boostering of anti-HLA antibodies.  相似文献   
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