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81.
Sensitivity of cervical cytology is suboptimal, especially in developing countries such as Mexico, despite available guidelines aimed at improving this. When obtaining cervical samples, whether the samples are taken from the transformation zone and whether abnormal cells are missing must be considered. Cervical secretions (CS) are always present in variable proportions, and when cleaning the cervix, better samples may be obtained. In this study, we analyzed samples obtained with or without cleaning the cervix, and compared their contents in order to determine the sensitivity and specificity of these two methods. Methods: Of 500 patients who underwent cytology and colposcopy, 271 (54.2%) required a second opinion due to a diagnosis of cervical intraepithelial neoplasia (CIN). CS was removed and compared with the clean, second sample (SS) using in both liquid-based cytology. The quality of samples according to the Bethesda System, the presence of CIN, and inflammatory reactions were recorded. The sensitivity and specificity were calculated using biopsy as the gold standard. Results: The SS resulted in a higher proportion of adequate samples being obtained (97.6% vs. 44.8%), and in increased sensitivity (88.2% vs. 58.8%). CIN was detected in the SS 26% more often than in the CS (34 vs. 27 samples), whereas inflammatory reactions were noted more often in the CS (91.4% vs. 74%). Conclusion: Cervical sampling including CS results in lower sensitivity and CIN detection rates, and in more inflammatory reactions. By excluding CS from cervical samples, the sensitivity could be improved and the false negative rate could be reduced.  相似文献   
82.
Serum lactic dehydrogenase (LDH) levels are mildly elevated in β-thalassemia major due to ineffective erythropoiesis. We reviewed the charts of 15 consecutive thalassemic children who underwent allogeneic, T-cell-depleted bone marrow transplantation (BMT) in our department during the last 3 years. Eleven patients had successful engraftment and are alive and well without evidence of disease, according to physical examinations, blood counts, and polymerase chain reaction (PCR) tests, with a median follow-up of 2 years. Two patients died due to transplantation-related complications, and two rejected the graft and received their backup autologous marrow. The LDH levels in the transplanted patients gradually decreased from an average of 952 ± 155 IU/L 10 days pre-transplant (N = 300–620) to 426 ± 56 IU/L at the day of transplantation, and stayed at approximately the same level post-transplant (489 ± 55 IU/L). By contrast, the LDH levels reverted to the pre-transplant value in those patients who rejected their marrow. The significance of this clinical observation for the pathophysiologic mechanism of intramedullary hemolysis and ineffective erythropoiesis in β-thalassemia major is discussed. © 1996 Wiley-Liss, Inc.  相似文献   
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Umbilical cord blood (CB) stem cells have been proposed for cell-based therapeutic applications for diverse diseases of the CNS. We hypothesized that tissue-engineering strategies may extend the efficacy of these approaches by improving the long-term viability and function of stem cell-derived neuronal progenitors. To test our hypothesis, we explored the survival and differentiation of human CB-derived neuronal progenitors (HUCBNP) in a three-dimensional (3D) collagen construct. In contrast to two-dimensional culture conditions, the cells survived in 3D for an extended period of time of more than 2 months. Under 3D conditions, HUCBNP underwent spontaneous neuronal differentiation, which was further enhanced by treatment with neuronal conditioned medium (CM) and nerve growth factor (NGF). Neurite outgrowth, quantified by assessing the fractal dimension (D f) of the complex neuronal networks, was significantly enhanced under 3D conditions in the presence of CM/NGF, concomitant with a reduced expression of the early neuronal marker nestin (1.9-fold), and increased levels of mature neuronal markers such as MAP-2 (3.6-fold), β-tubulin (1.5-fold), and neuronal specific enolase (6.6-fold) and the appearance of the synaptic marker synaptophysin. To assess the feasibility for clinical usage, HUCBNP were also isolated from frozen CB samples and cultured under 3D conditions. The data indicate the essential complete preservation of neurotrophic (survival) and neurotropic (neurite outgrowth) properties. In conclusion, 3D culture conditions are proposed as an essential step for both maintenance of CB neuronal progenitors in vitro and for investigating specific features of neuronal differentiation towards future use in regenerative therapy.  相似文献   
86.
The aim of the study was to assess the role of allogeneic stem cell transplantation (SCT) in patients diagnosed with BCR‐ABL1‐positive acute myeloid leukemia (AML). Fifty‐seven patients (median age, 48 years, range: 19‐67) with BCR‐ABL1 positive AML undergoing SCT were identified. The majority of the patients (70%) received a TKI before the transplant. At SCT 48 patients were in CR (45 in CR1), while 9 patients were transplanted in a more advanced stage of the disease. MRD was negative (BCR‐ABL1/ABL < 104) at time of SCT in 36.1% (14/40). After SCT, 16 (61.5%) out of 26 patients with MRD positive at transplantation reached MRD negativity. After a median follow‐up of 6.3 years (0.7–14.2), NRM, RI, LFS, OS, and GRFS at 5 years were 18.1%, 37%, 44.2%, 53.8%, and 32.1%, respectively. The cumulative incidence of acute GvHD grade II‐IV was 16.4%, incidence of chronic GvHD 24.9%, and of extensive cGvHD 21.4%, respectively. In patients who received SCT in CR1, 5‐yr NRM, RI, LFS, OS, and GRFS were 15.9%, 36.4%, 46.5%, 59.4%, and 34.9%, respectively. Univariate analysis showed that age (<50 vs. ≥50 years) was associated with RI (5‐yr: 22.7 vs. 50%), LFS (5‐yr: 61.9 vs. 31.8%), and GRFS (5‐yr: 52.4 vs. 18.2%), whereas MRD‐negative status before SCT was associated with an improved GRFS (38.9 vs. 16.7%). We conclude that the outcome of patients <50 years of age with BCR‐ABL1‐positive AML receiving allogeneic SCT in CR is relatively favorable, possibly reflecting the beneficial effect of the use of TKI.  相似文献   
87.
Peripheral blood cells from patients with myelodysplastic syndromes were assayed for B-cell and immunoregulatory T-cell functions. The B/T cell ratio in myelodysplastic patients (n = 11) was significantly higher than in controls (n = 12). These patients had a reduction in total T-cell (OKT3+) frequency and in T-cell subset (OKT4+/OKT8+) ratios. The response of patients' cells to both pokeweed mitogen (PWM) and phytohemagglutinin (PHA) was reduced, but patients' B cells responded normally to stimulation with Staphylococcus aureus Cowan (SAC). The levels of IgG and IgM detected in 7-day culture supernatants of PWM-stimulated patient and control cells were similar. Normal B-cell and immunoregulatory T-cell functions were subsequently demonstrated in allogeneic co-culture combinations of enriched T and B cells from patients and controls. The data presented indicate that the frequent infections of myelodysplastic patients are not causally related to impaired humoral mechanisms. The data also favor the possibility that the stem cell disorder in these syndromes is functionally expressed at a subsequent stage to the lymphoid differentiation pathway.  相似文献   
88.
目的:在成功分离人皮肤角质形成细胞的基础上,观察表皮生长因子受体在人皮肤角质形成细胞中的表达情况。方法:实验于2006-3/10在北京大学深圳医院中心实验室进行。采用dispase Ⅱ-trypsin两步消化法获取表皮基底层细胞,用小鼠皮肤成纤维母细胞滋养层和黄素腺嘌呤二核苷酸培养液进行培养。小鼠皮肤成纤维母细胞的预处理:向对数生长期的小鼠皮肤成纤维母细胞培养液中加入丝裂霉素C至终浓度为4mg/L,37℃下培养4h,弃去培养液,用D-Hank’s液洗3次,加入浓度为0.25g/L的胰蛋白酶消化,分离出细胞,离心(200g,5min),用黄素腺嘌呤二核苷酸培养液悬浮细胞,计数,以5.0×104/cm2的密度种于培养皿内,37℃、体积分数0.05的CO2培养箱下培养。角质形成细胞的培养:将分离的角质形成细胞悬浮在黄素腺嘌呤二核苷酸培养液中,以2.0×104/cm2的密度接种在前1天经丝裂霉素C处理的小鼠皮肤成纤维母细胞滋养层上,37℃、体积分数0.05的CO2培养箱下培养。24h换液,以后每3d换1次液。采用免疫细胞化学的方法检测表皮生长因子受体的表达,采用复合逆转录聚合酶链反应检测角质形成细胞中表皮生长因子受体mRNA的表达。结果:采用dispaseⅡ消化法分离了真皮和表皮,获得较多的角质形成细胞,可以避免真皮成纤维细胞的污染。人皮肤角质形成细胞在黄素腺嘌呤二核苷酸培养液中培养5d可见明显的集落,约10d可长满单层。免疫细胞化学显示表皮生长因子受体在细胞表面有明显的表达,复合逆转录聚合酶链反应显示表皮生长因子受体mRNA有明显的表达。结论:用小鼠皮肤成纤维母细胞滋养层和黄素腺嘌呤二核苷酸培养液可以较好地培养原代人皮肤角质形成细胞,表皮生长因子受体在细胞表面有明显的表达,这些结果为与表皮生长因子受体相关的皮肤病(如银屑病)的研究奠定了基础。  相似文献   
89.
目的:一些理论质疑富血小板血浆对骨前体细胞成骨分化的作用,本实验拟验证富血小板血浆对体外培养的人骨髓间充质干细胞成骨分化的抑制效应。方法:实验于2005-05/11在南方医科大学组织工程试验室(省级)完成。①实验方法:抽取6名健康志愿者髂前上棘骨髓5mL进行体外细胞培养扩增,静脉血10mL以二次离心法制得富血小板血浆。诱导骨髓间充质干细胞时富血小板血浆与骨髓间充质干细胞均来自同一个体。②碱性磷酸酶染色:取第4代骨髓间充质干细胞,分为两组:富血小板血浆组加入富血小板血浆使终浓度为100g/L,单纯血清培养组仅加入等量胎牛血清。培养后第7天进行碱性磷酸酶染色,阳性细胞为胞质中呈现黑色颗粒或块状沉淀。③矿化结节染色:取第4代骨髓间充质干细胞,分组同上。培养后第19天以0.1%茜素红-TrisHcl(pH8.3)37℃下放置30min,矿盐沉积染色阳性为红色。④Cbfa1基因表达:取第4代骨髓间充质干细胞,分组同上。培养后第3,7,12,16天RT-PCR法检测骨髓间充质干细胞Cbfa1基因的表达。⑤形态学观察:实验过程中使用相差显微镜观察各组细胞生长情况及形态学变化。结果:①骨髓间充质干细胞碱性磷酸酶染色结果:培养后第7天,富血小板血浆组碱性磷酸酶阳性细胞数量较单纯血清培养组明显减少,且阳性细胞内灰黑色颗粒也明显减少,为弱阳性。②骨髓间充质干细胞矿化结节染色结果:培养后第19天,单纯血清培养组可见细胞表面有较多的矿盐沉积,但未形成明显的矿化结节。富血小板血浆组细胞表面只有稀少的矿盐沉积。③骨髓间充质干细胞cbfa1mRNA的表达:培养后第3,7,12,16天,随着培养时间的延长单纯血清培养组与富血小板血浆组cbfa1基因表达量均逐渐增高,同一时间点两组间cbfa1基因的表达基本相似。④骨髓间充质干细胞形态学变化:富血小板血浆组骨髓间充质干细胞增殖旺盛,细胞达到单层汇合的时间较单纯血清培养组明显缩短。单纯血清培养组细胞在完全汇合后开始出现聚合现象(14~16d),但趋向性不明显,未完全形成团簇;富血小板血浆组细胞在完全汇合后未出现聚合现象,细胞密集生长。培养初期两组细胞以梭形为主,多角形细胞较少,培养至14~16d单纯血清培养组多角形细胞较富血小板血浆组增多。结论:富血小板血浆可抑制人骨髓间充质干细胞碱性磷酸酶的分泌与矿盐沉积,对人骨髓间充质干细胞成骨分化的直接效应是抑制其分化。  相似文献   
90.
目的:肝脏可溶性复合物具有保护肝脏、刺激肝组织再生等生物学活性,观察天然物质肝脏可溶性复合物对肿瘤细胞生长增殖的抑制作用.方法:实验于2006-05/2007-02在四川大学华西医院生物治疗国家重点实验室实验肿瘤研究室完成.①分离人胚胎、成年及新生小鼠肝脏组织,生理盐水清洗、剪碎、筛网过滤,用生理盐水制备混悬液,3 000 r/min离心,收集上清,制备肝脏可溶性复合物.②体外实验:用上述不同来源的肝脏可溶性复合物体外处理肿瘤细胞,四甲基偶氮唑盐比色法测定其对乳腺癌细胞EMT6增殖的影响.③体内实验:观察成年鼠肝脏可溶物质对乳腺癌细胞EMT6体内生长的抑制作用及其对荷瘤鼠生存状况的影响,包括不同给药剂量及不同给药途径两个实验,给药途径包括在接种肿瘤细胞部位的对侧腋下、同侧腋下、腹腔注射及灌胃等.结果:①体外实验显示不同来源的肝脏可溶性复合物能明显抑制肿瘤细胞EMT6增殖率,肿瘤增殖抑制率均显著高于血清白蛋白处理组(P<0.05),并呈剂量依赖性.②成年鼠肝脏可溶物质8mg/L组抑瘤率高于2,4 mg/L组(P<0.05),未观察到明显毒副效应.③比较不同给药途径,成年鼠肝脏可溶物质同侧注射组的抑瘤率较其他3组的抑瘤率高(P<0.05),各成年鼠肝脏可溶物质给予组的体质量增长率比相应生理盐水对照组高(P<0.05).④与相应生理盐水对照组比较,在同侧腋下注射成年鼠肝脏可溶物质的小鼠生存期明显延长(P<0.05).结论:肝脏可溶性复合物具有抑制肿瘤细胞生长的作用,并且呈一定的剂量依赖性.不同的给药途径中,在接种肿瘤细胞部位的同侧腋下给药抑瘤效果最好.  相似文献   
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