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21.
见于湖南江华县的一例慢泳血红蛋白α链变种,其先证者为汉族青年,属杂合子。家系调查发现其父、大姐和弟均携有同样的异常Hb。血液学常规检查一般正常。除先证者肝在肋缘下0.5cm扪及外,无任何临床症状。经一级结构分析,确证此例为HbG一台中[α74(EF3)Asp→His]。功能观测其氧平衡特征与HbA无差异。这是见于湖南的首例。  相似文献   
22.
通过对97例截瘫住院患者连续10年的Hb测定结果进行回顾性分组研究,结果表明,无并发症组10年中Hb分布较一致,其均值与正常人比较无显著性差异(P>0.05),但12.3%的病例Hb水平低于正常人下限;当截瘫并发泌尿系感染、尿毒症或难治性褥疮等病症时,则导致Hb水平的降低。提出Hb测定结果,可做为在整体水平上观察截瘫患者的治疗及康复效果的指标。  相似文献   
23.
Abstract Fructosamine assay, which is used in diagnosing and monitoring diabetic patients, is compared with the hemoglobin and plasma glucose assays in children and adolescent insulin-dependent diabetes mellitus patients. We demonstrated that the gingival index scores were correlated with fructosamine values in insulin-dependent diabetes mellitus patients but not in non-diabetic controls. We also found that there was no correlation between gingivitis scores and fasting plasma glucose and HbAlc values. Periodontitis was found to be rare in diabetic children and adolescents.  相似文献   
24.
继青海、甘肃、新疆、河南等地发现Hb Punjab杂合子后,杂们又在安徽省阜阳地区发现两例HbD纯合子,级一级结构分析,确诊为HbDpunjabβ121(CH4)Clu→Gln。这一发现为探讨该地区回族中异常Hb发生率高的原因,研究各民族的亲缘关系以及Hb变对人类健康与的影响提供了遗传学资料。  相似文献   
25.
妊娠期低水平铅暴露对新生儿钙磷代谢及造血系统的影响   总被引:2,自引:0,他引:2  
目的 :研究妊娠期低水平铅暴露对新生儿钙磷代谢及造血系统的影响。 方法 :分别测定 79例汉族及5 9例维吾尔族 (维族 )母亲及新生儿脐血铅、钙、磷、碱性磷酸酶、血红蛋白、红细胞游离原卟啉的含量 ,分析脐血铅对新生儿钙、磷、碱性磷酸酶及血红蛋白、红细胞游离原卟啉的影响。 结果 :(1)汉族产妇血铅 6 3 87μg/L ,新生儿脐血铅 4 7.71μg/L ,维族产妇血铅 87 92 μg/L ,新生儿脐血铅 6 1.5 7μg/L ,维族产妇及新生儿脐血铅均高于汉族产妇及新生儿脐血铅含量 (P <0 .0 5 ~ 0 .0 1) 。 (2 )以脐血铅 10 0 μg/L为界将新生儿分为高铅组和低铅组 ,两组血钙相比差异有统计学意义 (P <0 .0 1) ,而两组血红蛋白及红细胞游离原卟啉相比差异均无统计学意义 (P >0 .0 5 )。 结论 :妊娠期低水平铅暴露可致新生儿血钙下降 ,但对新生儿血红蛋白及红细胞游离原卟啉则无影响  相似文献   
26.
Studying the effects of microgravity on cell differentiation will enhance our understanding of fundamental biology and is indispensable for a sustained space program. Rauscher murine erythroleukemic cells were chosen as a model system to study erythroid cell differentiation aboard the International Space Station because these cells undergo differentiation in response to the natural inducer, erythropoietin, as well as various chemical inducers. We have now developed a method to quantify hemoglobin in Rauscher cells after weeks of fixation and storage required for such space biology experiments. By exploiting the pseudoperoxidase activity of hemoglobin and by using reagents that yield a soluble chromophore that freely passes out of fixed cells, we developed a highly specific and sensitive assay applicable to cells fixed as long as 4 months.  相似文献   
27.
背景 目标范围内时间(TIR)作为血糖管理的新指标,与短期血糖波动相关,是否与长期血糖变异性相关尚不清楚。目的 探讨老年男性2型糖尿病患者TIR与长期随访期间糖化血红蛋白(HbA1c)变异系数、HbA1c变异性评分(HVS)的关系。方法 选取2007年1月至2011年1月在解放军总医院第二医学中心住院行动态血糖监测(CGM)的老年男性2型糖尿病患者200例,根据患者基线TIR水平,将其分为TIR≥85%组(n=141)和TIR<85%组(n=59)。对受试者随访观察(12.5±1.1)年,比较两组长期随访期间HbA1c变异系数和HVS。采用Pearson相关、多元线性回归分析TIR与HbA1c变异系数、HVS的关系。结果 TIR<85%组患者的长期HbA1c变异系数[(9.7±3.8)%比(8.2±4.5)%,P=0.028)]、HVS[(48.7±20.4)分比(32.5±20.8)分,P<0.001)]均明显高于TIR≥85%组。Pearson相关分析结果...  相似文献   
28.
Hemoglobin (Hb) solutions can cause vasoconstriction and activation of intravascular coagulation. Because the endothelium plays a major role in the regulation of vascular tone and hemostasis, a study was conducted of human umbilical vein endothelial cells (EC) incubated with various Hbs. Cell injury was evaluated by electron microscopy and the release of lactic dehydrogenase, H2O2, and procoagulant "tissue factor." Cell reaction was assessed by the measurement of 6-keto-prostaglandin F (PGF)1 alpha (metabolite of prostacyclin) and thromboxane B2 (metabolite of thromboxane A2). Incubation with unmodified bovine hemoglobin for 24 h caused no cell injury and a reaction characterized by 48.4 +/- 8.2% increase in 6-keto-PGF1 alpha production, accompanied by 40.2 +/- 9.4% reduction in thromboxane (Tx)B2 (compared with a control group of EC incubated with saline solution). Incubation with a nonpure Hb solution (Hb plus red blood cell membrane aminophospholipids; a-PLs) caused cell injury with significant release of tissue factor, plus a reaction characterized by 97.5 +/- 12.5% increase in TxB2 production accompanied by 25.3 +/- 3% reduction in 6-keto-PGF1 alpha. A second nonpure Hb [Hb plus bacterial environmental endotoxin (E)] caused cell injury, the release of tissue factor, and increased production of both prostaglandins, with greater release of TxB2 (197 +/- 17%) than of 6-keto-PGF1 alpha (112 +/- 8.3%). These data indicate that the endothelium reacts differently to pure and nonpure hemoglobins. The biocompatibility of Hb solutions, with regard to vasoconstriction and activation of intravascular coagulation, depends on the absence of stromal a-PLs and bacterial E.  相似文献   
29.
Summary Hemoglobin (Hb) M-Saskatoon, a variant of methemoglobin, is characterized by mild hemolysis. It is caused by the substitution of a histidine by a tyrosine at the 63rd amino acid residue of the -globin chain. Amplification and sequence analysis of genomic -globin DNA from an Indonesian boy diagnosed as having the more severe disease thalasemia demonstrated the presence of a C to T transition at nucleotide 473 in one of the two -blogin genes resulting in a histidine to tyrosine substitution at 63rd residue. This amino acid change matched with that reported in Hb M-Saskatoon. This nucleotide change abolished a recognition site for the restriction endonucleaseNlaIII.NalIII digestion of the corresponding -globin DNA amplified from the patient's parents indicated that the mutation was inherited through from his mother. This result shows that the world-wide distribution of Hb M-Saskatoon extends to Indonesia, where it was not previously identified. Possible causes of the unusually severe symptoms observed in the case are discussed.  相似文献   
30.
The isolation and analysis of nucleated fetal cells (NFCs) from maternal blood may represent a new approach to noninvasive prenatal diagnosis. Although promising, these techniques require highly accurate separation of NFCs from nucleated cells of maternal origin; the two major problems limiting these techniques are the relative rarity of fetal cells in maternal blood and the need to establish their fetal origin. We now report a novel procedure that has allowed accurate separation of NFCs from maternal cells. The technique reported involves direct micromanipulator isolation of histochemically identified hemoglobin F‐positive nucleated cells to obtain fetal nucleated red blood cells (FNRBCs) of high yield and purity. Using this technique, followed by cell‐by‐cell multicolor fluorescence in situ hybridization (FISH) analysis of purified FNRBCs, we were able to detect some of the most common human aneuploidies (including Down syndrome, Klinefelter syndrome, and trisomy 13) in 33 pregnant women referred for amniocentesis. The procedure used, which can be completed in <72 hrs, produced complete concordance with the results of amniocentesis. We also confirm findings of prior studies suggesting that the number of FNRBCs in maternal circulation is remarkably higher in abnormal pregnancies than in normal pregnancies, especially in women carrying a fetus with trisomy 21. © 2001 Wiley‐Liss, Inc.  相似文献   
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