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581.
We previously reported isolation of human T-cell leukemia virus II (HTLV-II) from a second patient (N.R.A.) with atypical hairy cell leukemia. Follow-up analysis of the characteristics of the patient's HTLV-II infection over a 2-year period has revealed that the patient had two coexistant lymphoproliferative disorders. Oligoclonally integrated HTLV-II was detected in DNA extracted from the patient's peripheral blood mononuclear cells on separate occasions greater than 1 year apart, similar to integration of HTLV-I seen in adult T cell leukemia/lymphoma. Although integrated provirus was readily detected, no HTLV-II viral RNA expression was seen in fresh peripheral blood lymphoid cells. Although the patient's peripheral blood consistently contained a majority of atypical lymphoid cells with a T cell antigenic phenotype, he ultimately developed extensive pleural, hepatic and soft tissue infiltration with malignant Tac+, tartrate-resistant, acid phosphatase-positive (TRAP+) B cells of clonal origin. To further characterize the role of HTLV-II, the patient's peripheral blood mononuclear cells were fractionated into four enriched subpopulations at autopsy. Oligoclonally integrated HTLV-II was detected in DNA from a T cell-enriched fraction and a CD8+ T cell-enriched fraction, but not in a CD4+ T cell-enriched fraction, a non-T cell fraction, or in B cells obtained from the malignant pleural effusion. We conclude that the patient harbored two distinct lymphoproliferative disorders, a TRAP+, Tac+ B cell malignancy consistent with hairy cell leukemia that did not contain HTLV-II and a Tac-, CD8+ lymphoproliferative syndrome with oligoclonally integrated HTLV-II.  相似文献   
582.
A Bangladeshi family is described in which the genes for both hemoglobin E (Hb E) and pyrimidine 5' nucleotidase deficiency are segregating. An individual homozygous for both these conditions has a severe hemolytic anemia, whereas family members who are homozygous for Hb E are asymptomatic and those homozygous for pyrimidine 5' nucleotidase deficiency have the mild hemolytic anemia that is characteristic of this disorder. Globin-chain synthesis experiments have shown that the mechanism underlying the interaction between these two genotypes is a marked decrease in the stability of Hb E in pyrimidine 5' nucleotidase-deficient red blood cells (RBCs). It has also been found that in the enzyme-deficient RBCs in which Hb E is highly unstable, free alpha-chains, though not beta E-chains, acoumulate on the membrane. In view of the increasing evidence that the hemolysis associated with pyrimidine 5' nucleotidase deficiency results not only from an increase in the level of erythrocyte pyrimidines, but also from inhibition of the hexose monophosphate shunt activity in young erythrocytes, it is likely that the marked instability of Hb E in the enzyme-deficient cells results from oxidant damage acting on a mildly unstable Hb variant. These observations may have important implications for the better understanding of the pathophysiology of Hb E/beta-thalassemia, globally the commonest important form of thalassemia.  相似文献   
583.
目的:在兔固定的膝关节内定期注入透明质酸钠,观察关节内外组织的变化。方法:实验于2003-10/2004-04在大连医科大学完成。实验分组:新西兰兔24只,随机分为透明质酸钠组、生理盐水组、单纯对照组,每组8只。实验干预:用树脂绷带将兔右膝关节固定于伸直位,膝关节注射部位开窗,左膝自由活动(自身对照侧)。透明质酸钠组膝关节腔内注入透明质酸钠0.1mL,生理盐水组注射同等剂量的生理盐水,单纯对照组不向关节内注射任何药物,每周1次,共5次。实验评估:5周后麻醉下处死动物,去除外固定,采用改良Clarke-Weeknesser关节伸屈范围检查标准测量右膝关节的活动范围;采用改良的Rydell-Balazes肉眼粘连评分标准评估膝关节内纤维粘连情况;光镜下观察股间肌、股直肌、髌内外侧支持带的纤维变性情况。结果:动物饲养过程中死亡4只,进入结果分析透明质酸钠组7只,生理盐水组6只,单纯对照组7只。①右膝关节的活动范围:透明质酸钠组大于生理盐水组和单纯对照组[(37.86±2.94)°,(15.67±2.23)°,(14.29±1.96)°,P<0.01]。②膝关节内纤维粘连评分:透明质酸钠组小于生理盐水组和单纯对照组(1.44±0.49,3.33±0.44,3.44±0.57,P<0.01)。③光镜下透明质酸钠组股间肌、股直肌的纤维变性较生理盐水组和单纯对照组减轻,髌内外侧支持带胶原纤维成分的变化也减轻。结论:在固定的兔膝关节内注射透明质酸钠不但可以明显抑制关节内的纤维性粘连;还可以抑制关节外股间肌、股直肌、髌内外侧支持带的组织变性。  相似文献   
584.
目的:为寻找采集外周血造血干细胞更合适的手段,探讨间断流动式血细胞分离机采集外周血造血干细胞的效果。方法:选择中山大学第五附属医院血液风湿科2004-2006年12例行外周血造血干细胞移植住院患者。①实验对象:供者5例,男1例,女4例,一般状况良好,与患者关系为同胞妹妹3例,同胞弟弟1例,同胞姐姐1例;患者7例,男3例,女4例,23~62岁,7例为自体移植,5例为异基因移植。血液系统疾病患者9例(非霍奇淋巴瘤3例,急性淋巴细胞白血病2例,急性髓细胞白血病2例,慢性粒细胞白血病1例,骨髓增生异常综合征1例);自身免疫性疾病3例(重型系统性红斑狼疮2例,难治复发性类风湿关节炎合并干燥综合征1例)。②实验过程:每位供/患者均知情同意并签署知情同意书。对于自体患者,根据患者的疾病类型采取不同的干细胞动员化疗方案,联合化疗后7~10d,待白细胞下降至最低点,一般为≤1.0×109 L-1时,给予粒细胞集落刺激因子5μg/kg皮下注射,白细胞升至3.0×109 L-1时开始采集;对于allo-PBSCT供者直接给予粒细胞集落刺激因子5μg/kg,皮下注射,1次/d,共5d,同时应用流式细胞仪检测CD34 细胞数,至白细胞升至≥20.0×109 L-1或当CD34 细胞升高>20个/μL时采用增强型多功能血细胞分离机PBSC程序卡采集健康供者和患者外周血造血干细胞。③实验评估:分析采集效率、血液学参数、不良事件发生率、以及供、受者ABO血型不合的患者回输干细胞溶血反应等情况。结果:12例供者、患者均进入结果分析。①共进行了24次采集,其中1次采集1例,2次采集7例,3次采集3例,平均循环次数(25±5)次,采集时间(228±32)min,处理血量(7234±1205)mL,复方枸橼酸钠溶液用量为(623±96)mL,干细胞收集量为(102±21)mL,CD34 细胞采集效率为(54.3±30.7)%,细胞计数示白细胞为(156±34)×109 L-1,单个核细胞为(79.7±13.2)×109 L-1,流式细胞仪检测CD34 细胞为(10.30±4.38)×106/kg受者体质量。②不良反应轻微,24次采集过程中出现不良反应6次均为枸橼酸盐所致低钙血症反应。血红蛋白和血小板与采集前相比分别下降9.36%和11.10%。供、受者ABO血型不合的3例患者在输注造血干细胞悬液后均未出现溶血反应。③12例均获造血功能重建,无移植相关死亡。结论:用间断流动式血细胞分离机采集外周血造血干细胞效果良好,不良反应轻微,能有效的减少被采集者红细胞、血小板的丢失,对供、受者ABO血型不合者不需去除造血干细胞悬液中的红细胞,值得临床应用。  相似文献   
585.
目的:培养条件是影响骨髓间充质干细胞生物学特性的重要因素。实验考察换液频率对兔骨髓间充质干细胞增殖分化及代谢特性等的影响。方法:实验于2005-03/2005-06在华东理工大学生物反应器工程国家重点实验室完成。①实验材料:1月龄新西兰大白兔购自上海市淞江车墩实验动物良种场。实验过程中对动物处置符合动物伦理学标准。②实验方法:采用密度梯度离心法从兔股骨骨髓中分离得到骨髓间充质干细胞,体外培养扩增后,取生长良好的第3代细胞分别以24,48,72h时间间隔进行换液培养。③实验评估:观察细胞形态学变化,测定细胞生长曲线同时进行乳酸和氨代谢分析,并对几种条件下收获的细胞进行集落形成和成骨分化检测。结果:①每24h换液的细胞最早进入对数生长期,第5天达到增殖顶点,最大细胞数目可达3.44×105,分别是48h和72h换液频率的1.43倍和1.71倍。②每48h换液条件下收获的细胞具有最强的集落形成能力,明显高于每24h和每72h换液条件下收获的细胞。③3种换液频率条件下收获的细胞经成骨诱导后茜素红染色均为阳性,其中每48h换液的细胞胞外钙基质分泌最高。④3种换液频率条件下细胞的代谢曲线无明显差异,乳酸和氨均维持较低浓度,分别在5mmol/L和2mmol/L以下。结论:①换液频率对骨髓间充质干细胞的影响具有双向性。提高换液频率促进骨髓间充质干细胞的增殖,同时也加速了干细胞特性的丢失,导致集落形成能力和成骨分化能力下降。②普遍采用的三四天换液不能提供适合骨髓间充质干细胞生长同时利于干细胞特性维持的营养环境,提示可通过常规培养条件的优化使其有利于骨髓间充质干细胞执行对称的细胞分裂。  相似文献   
586.
新生儿免疫性血小板减少症(Neonatalalloimmunethrom-bocytopenia,NATP)发病原因是由于母体产生针对胎儿特异性血小板抗原的IgG抗体,并发生抗原抗体反应。胎儿特异性血小板抗原来自父亲。NATP发病率约为0.l%。NATP占新生儿血小板减少症的3%和重度血小板减少(血小板计数<50×109  相似文献   
587.
Plasma exchange (PE) and intravenous gammaglobulin (IVGG) are potentially effective therapies in immune thrombocytopenic purpura (ITP). In this study, eight patients refractory to IVGG and to prednisone were treated with a protocol of combined PE and IVGG therapy using a single PE on each of 3 consecutive days, followed by 2 consecutive days of IVGG at 1 g per kg. Four of the eight patients responded to the combined therapy with a mean peak platelet count of 132,000 per microliter (range, 74,000 to 225,000/microliter). Responses lasted approximately 2 weeks. These four patients were among the five who had initially responded to IVGG before becoming refractory; none of the three patients without an initial response to IVGG responded to the combined therapy. Age, duration of disease, and splenectomy status did not appear to be related to response to the combined therapy. Two patients began maintenance treatment (1 PE followed by 1 g/kg IVGG on the same day), but both became unresponsive after three treatments. PE combined with IVGG may be a useful treatment for some patients with refractory ITP who have uncontrollable bleeding or require major surgery. The development of resistance to IVGG effect may be mediated by an increase in the level of antiplatelet antibodies. PE, by lowering antiplatelet antibody levels, may then allow IVGG infusion to be effective again in elevating the platelet count.  相似文献   
588.
BACKGROUND: At present, tens of thousands of United States blood donors who are at low risk for human immunodeficiency virus type 1 (HIV-1) infection are indefinitely deferred. These persons are repeatably reactive for HIV-1 antibody in enzyme immunoassay (EIA) and are indeterminate in Western blot. STUDY DESIGN AND METHODS: To determine the significance and persistence of anti-HIV-1 reactivity in plasma from volunteer blood donors with HIV-1-indeterminate Western blots, 66 donors were retested for HIV-1 antibody by the same manufacturers' EIA and Western blot 5 to 7 years after the initial Western blot. In addition, donors' peripheral blood mononuclear cells were tested by polymerase chain reaction (PCR) for HIV-1 DNA gag sequences. RESULTS: Thirty-five (53%) of 66 donors were still repeatedly reactive for HIV-1 on EIA and indeterminate on Western blot, 23 (35%) were negative on EIA and indeterminate on Western blot, 7 (11%) were negative in EIA and Western blot, and 1 (2%) was repeatedly reactive on EIA and negative on Western blot. Donors with persistently indeterminate Western blots had a band pattern nearly identical to that on the original Western blot. No donor was positive in Western blot, p24 antigen, or PCR testing. No donor had signs or symptoms of HIV-1 infection. CONCLUSION: Long-term follow-up of Western blot-indeterminate blood donors does not reveal evidence of HIV-infection. A mechanism to return these donors to the donor pool should be considered.  相似文献   
589.
中国卫生地理信息系统基础数据库的构建   总被引:16,自引:3,他引:16       下载免费PDF全文
目的:构建可用于中国卫生地理信息系统(GIS)应用研究的基础数据库,以合理应用已有的数据资源,并成为一个空间决策系统。方法:采集不同资料来源,经统一标化后构成基本资料源。主要的资料源包括:(1)覆盖中国地区的卫星遥感图片库;(2)GIS数字化地图库;(3)疾病资料库与相关模型库。结果:已获卫星遥感图片库中的植被指数遥感图片、地面温度遥感图片、数字化高程图片、数字化土地利用图片等;GIS数字化地图库中的中国行政区划数字化地图、环境数据矢量地图、人口分布图、气象资料分布图等;疾病资料库与相关模型库中包括了多种疾病的调查报告、疾病防治年报表等资料,以及疾病的传播模型和媒介/中间宿主潜在自然孳生地模型,及恶性肿瘤发病因素相关图。结论:该数据库的构建使不同来源的数据达到统一性,数据库收集的数据量以足能为国内卫生专业人员应用为前提,希望通过更多疾病的应用,使数据库得以完善。  相似文献   
590.
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