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61.
To identify new markers of minimal residual disease (MRD) in B-lineage acute lymphoblastic leukemia (ALL), gene expression of leukemic cells obtained from 4 patients with newly diagnosed ALL was compared with that of normal CD19(+)CD10(+) B-cell progenitors obtained from 2 healthy donors. By cDNA array analysis, 334 of 4132 genes studied were expressed 1.5- to 5.8-fold higher in leukemic cells relative to both normal samples; 238 of these genes were also overexpressed in the leukemic cell line RS4;11. Nine genes were selected among the 274 overexpressed in at least 2 leukemic samples, and expression of the encoded proteins was measured by flow cytometry. Two proteins (caldesmon and myeloid nuclear differentiation antigen) were only weakly expressed in leukemic cells despite strong hybridization signals in the array. By contrast, 7 proteins (CD58, creatine kinase B, ninjurin1, Ref1, calpastatin, HDJ-2, and annexin VI) were expressed in B-lineage ALL cells at higher levels than in normal CD19(+)CD10(+) B-cell progenitors (P <.05 in all comparisons). CD58 was chosen for further analysis because of its abundant and prevalent overexpression. An anti-CD58 antibody identified residual leukemic cells (0.01% to 1.13%; median, 0.03%) in 9 of 104 bone marrow samples from children with ALL in clinical remission. MRD estimates by CD58 staining correlated well with those of polymerase chain reaction amplification of immunoglobulin genes. These results indicate that studies of gene expression with cDNA arrays can aid the discovery of leukemia markers. (Blood. 2001;97:2115-2120)  相似文献   
62.
The immunophenotypes of lymphoblasts from children with newly diagnosed T-cell acute lymphoid leukemia (T-ALL, n = 101) or T-cell non-Hodgkin lymphoma (T-NHL, n = 31) were analyzed to correlate stage of thymocyte differentiation with clinical features and outcome. The 67 boys and 34 girls with T-ALL were 1 month to 18 years old (median, 8 years) with leukocyte counts ranging from 2 to 810 x 10(9)/L (median, 55 x 10(9)/L). Eighteen of these patients were black, and 70 had a mediastinal mass. Twenty-six boys and five girls with a median age of 9 years (range, 1 to 20 years) had T-NHL. Seven of these patients were black, and 24 had a mediastinal mass. The distributions of thymocyte developmental stages (early [CD7+], intermediate [CD1+ and/or CD4+ and/or CD8+], and mature [CD3+]) in cases of T-ALL and T-NHL were significantly different: 34%, 43%, and 23% v 6%, 62%, and 32% (P = .02). A comparison of the patients' clinical features according to the maturational stage of thymocytes failed to disclose significant differences in the majority of characteristics studied. However, patients with mature-stage T-NHL, with or without the addition of subjects with mature-stage T-ALL, were less likely to have a mediastinal mass (P = .02 for both comparisons). Those with intermediate-stage T-cell malignancy (T-ALL and T-NHL combined) were the subgroup most likely to have a mediastinal mass (P = .01). Response to remission induction therapy was significantly worse in the T-ALL subgroup with an early-stage phenotype: a failure rate of 21% v 0% and 6% for the two more differentiated phenotypic subgroups (P = .007). Event-free survival was not affected by thymocyte maturational stage in cases of either T-ALL or T-NHL. Despite evidence of clinical heterogeneity among the maturational stages of T-cell malignancies in children, these developmental subdivisions do not appear to be critical determinants of outcome once remission is achieved. We conclude that such phenotypes need not be included in the stratification plans for clinical trials using common induction treatment.  相似文献   
63.
Previous studies have described racial and socioeconomic disparities in the treatment of infertility. Patient factors such as attitudes and awareness may be contributing factors. Since primary care is often the setting that serves as an entry into other areas of medicine, we sought to evaluate men's attitudes and awareness of male infertility in the primary care setting. To do this, we performed a cross-sectional survey of men's attitudes toward men's health issues in 210 men from two primary care clinic waiting rooms in Atlanta, Georgia. The survey was self-administered with closed-ended question items and was approximately 20 min in length. Of the 310 men approached, 210 agreed to participate and returned completed surveys. Overall, 52% of men said they were "very" or "somewhat" familiar with infertility and 25% were familiar with treatments for infertility. Some men had heard of surgery (21%) and medication (35%) as treatments for male infertility. Awareness and familiarity with the condition was greater in high socioeconomic status men (i.e. college graduates or those with income 〉$100 k per year) but did not differ by race on multivariate analysis. Attitudes toward infertility varied by race with non-Caucasian men being more likely to indicate that infertility is a serious condition, to be concerned about infertility, and to believe it decreases a man's quality-of-life. Therefore, a lack of awareness, but not negative attitudes, may contribute to previously-described disparities in the treatment of infertility.  相似文献   
64.
Clinical Rheumatology - SAPHO (synovitis, acne, pustulosis, hyperostosis, and osteitis) syndrome is a poorly known disease with cutaneous and osteo-articular manifestations requiring a...  相似文献   
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66.
目的:灰色模型是运用一定的数学方法使信息不完全明确的系统经数据处理后能得到较明确结果的一种数学预测模型,体外细胞培养的影响因素较多,属于信息不完全明确的灰色系统,故运用灰色GM(1,1)模型对成骨细胞增殖、分化的变化规律进行预测,验证模型在体外细胞培养中的可应用性。方法:实验于2005—11/2006—03在广东医学院药理教研室完成。①实验过程:应用酶序列消化分离培养法培养新生大鼠颅骨成骨细胞;用MTT法测定体外培养成骨细胞在不含血清培养液A值,以了解成骨细胞的增殖情况;对硝基苯磷酸盐法观察体积分数为0.01的胎牛血清培养液对体外培养成骨细胞分泌碱性磷酸酶活性的影响,代表成骨细胞的分化情况。②灰色GM(1,1)模型建立:运用灰色系统理论,通过SAS8.1软件对体外培养成骨细胞MTT值和碱性磷酸酶OT值进行分析和预测。结果:运用灰色系统理论的后验差检验方法对模型进行检验,MTT这一指标的平均相对误差为4.4%,碱性磷酸酶这一指标的平均相对误差为7.04%,后验差比值为0.048和0.315,综合评定该模型为“好”。结论:灰色GM(1,1)模型对体外培养成骨细胞MTT值和碱性磷酸酶的OT值变化的预测精度高,结果可靠。体外培养成骨细胞MTT值和碱性磷酸酶的OT值的变化可用灰色GM(1,1)模型进行预测。  相似文献   
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68.
B cell precursors transiently express a pre–B cell receptor complex consisting of a rearranged mu heavy chain, a surrogate light chain composed of λ5/14.1 and VpreB, and the immunoglobulin (Ig)-associated signal transducing chains, Igα and Igβ. Mutations in the mu heavy chain are associated with a complete failure of B cell development in both humans and mice, whereas mutations in murine λ5 result in a leaky phenotype with detectable humoral responses. In evaluating patients with agammaglobulinemia and markedly reduced numbers of B cells, we identified a boy with mutations on both alleles of the gene for λ5/14.1. The maternal allele carried a premature stop codon in the first exon of λ5/14.1 and the paternal allele demonstrated three basepair substitutions in a 33-basepair sequence in exon 3. The three substitutions correspond to the sequence in the λ5/14.1 pseudogene 16.1 and result in an amino acid substitution at an invariant proline. When expressed in COS cells, the allele carrying the pseudogene sequence resulted in defective folding and secretion of mutant λ5/14.1. These findings indicate that expression of the functional λ5/14.1 is critical for B cell development in the human.  相似文献   
69.
WM. Munk 《Lancet》1840,34(878):480-483
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70.
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