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51.
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   
52.
Risk factors for avascular bone necrosis in systemic lupus erythematosus   总被引:6,自引:0,他引:6  
OBJECTIVE: To study the predictive factors for avascular necrosis (AVN) of bone in patients with systemic lupus erythematosus (SLE). METHOD: The records of 38 SLE patients who developed clinically apparent AVN during the course of their disease were reviewed. Information on clinical presentation, corticosteroid usage and autoantibody profiles was obtained, and comparison was made between these patients and 143 consecutive control SLE patients who did not have AVN. RESULTS: The point prevalence of AVN in our SLE population was 12%. Patients with AVN, when compared with controls, had a significantly higher incidence of neurological disease (39% vs 14%; P < 0.001) and Cushingoid body habitus after steroid treatment (79% vs 53%; P = 0.004). The highest cumulative prednisolone dose in 1 and 4 months was significantly higher in the AVN group than the controls (1.8 vs 1.1 and 4.5 vs 2.8 g, respectively; P < 0.01 in both) and showed a linear trend with the incidence of AVN (chi2 test for trend, P < 0.01 in both). Lupus anticoagulant was associated with AVN (P = 0.02, odds ratio 2.88 [1.14- 7.28]). Logistic regression analysis revealed that the highest cumulative prednisolone dose administered in 4 months, the maximum and mean daily prednisolone dosage, and the lupus anticoagulant were independent risk factors for AVN. CONCLUSIONS: Corticosteroid remains the major predisposing factor for AVN in SLE. Patients who require an initial high-dose steroid for disease control are at risk of AVN, especially if they are positive for the lupus anticoagulant or develop Cushingoid habitus after steroid treatment. High-risk patients should be closely monitored so that early AVN can be diagnosed by sensitive techniques such as magnetic resonance imaging and radioisotope bone scanning.   相似文献   
53.
Chang  CS; Sassa  S 《Blood》1985,65(4):939-944
Physicochemical and immunologic properties of delta-aminolevulinate (ALA) dehydratase in human K562 erythroleukemia cells were examined. ALA dehydratase activity was found to increase in K562 cells after treatment with butyric acid or selenium oxide. Enzyme activity in untreated K562 cells was comparable to that in normal adult erythrocytes but was increased three- to six-fold in K562 cells treated with 1.2 mmol/L butyric acid or 0.03 mmol/L selenium oxide. The Michaelis-Menten constant (Km), the inhibitor constant (Ki), and elution profile by diethylaminoethyl (DEAE) cellulose chromatography were similar for ALA dehydratase from K562 cells and normal human adult and human fetal erythrocytes. However, ALA dehydratase from K562 cells did not react with a monospecific rabbit antibody against ALA dehydratase purified from normal adult erythrocytes, although the antibody reacted with the enzyme from normal adult and fetal red cells. These findings indicate that ALA dehydratase in K562 cells is immunologically distinct from the normal enzyme.  相似文献   
54.
Despite current guidelines that all reproductive age women receive preconception care (PCC), most US women do not, especially women with a prior birth. The objective of our study was to identify factors associated with receipt of PCC health promotion counseling among Maryland women and to assess whether prior birth outcome affects receipt of counseling. We analyzed Maryland pregnancy risk assessment monitoring system data for a stratified random sample of women with a live birth in 2009–2010; 3,043 women with PCC data were included in the analysis. The dependent variable was receipt of any PCC counseling, and the primary independent variable, prior pregnancy outcome (no prior live birth, term, preterm). 33.1 % of the weighted sample received PCC. Odds of PCC were similar for women with a history of prior prior preterm birth (aOR 1.00, 95 % CI 0.57–1.78) and no prior live birth, but decreased for women with a prior full term delivery (aOR 0.69, 95 % CI 0.51–0.94). They were decreased for women with unintended births (aOR 0.36, 95 % CI 0.26–0.51) and increased for women with a diagnosis of asthma (aOR 1.74, 95 % CI 1.05–2.89) or diabetes (aOR 2.79, 95 % CI 1.20–6.45), who used multivitamins (aOR 2.58, 95 % CI 1.92–3.47), and had dental cleanings (aOR 1.60, 95 % CI 1.16–2.18). Although selected preventive health behaviors and high-risk conditions were associated with PCC, most women did not receive PCC. Characterization of women who do not receive PCC health promotion counseling in Maryland may assist in efforts to enhance service delivery.  相似文献   
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经肛门内镜显微手术切除直肠肿瘤   总被引:14,自引:3,他引:14  
目的评价经肛门内镜显微手术(TEM)切除直肠绒毛状腺瘤和早期直肠癌的应用效果。方法分析我院总结1995年11月至2001年12月27例TEM手术的临床资料。结果本组患者肿瘤直径中位值2.5cm,肿瘤下缘与齿状线距离(8.9±3.4)cm,肿瘤侵犯直肠周径范围(35.7±17.5)%。平均手术时间(109±46)min。平均住院日4.5d。无围手术期死亡。手术并发症有尿潴留、暂时性大便失禁和慢性阻塞性肺病(COPD)复发。术中2例切穿至腹腔,即刻内镜下修补成功。切缘100%瘤细胞阴性。病理示直肠绒毛状腺瘤14例、直肠腺癌13例,后者包括pTis2例,pT16例和pT25例。直肠癌腔内超声肿瘤T分期符合率为84.6%。5例pT2中2例中转前切除术,1例接受术后放疗,2例无附加任何治疗。平均随访18个月,所有病例无局部复发。死亡2例,但无复发迹象。结论TEM易行且安全,是直肠绒毛状腺瘤和部分T1直肠癌的治愈性手术,也可作为T2直肠癌的姑息性治疗手段。  相似文献   
59.
目的探讨经肛门内镜显微手术(transanal endoscopicmic rosurgery,TEM)治疗直肠绒毛状腺瘤和早期直肠癌的疗效。方法1995年11月~2003年12月,我院行TEM治疗直肠肿瘤31例。全麻下根据肿瘤位置选择合适的体位,经肛门插入特殊的手术直肠镜,保持CO2充气状态,在立体视镜和腔镜系统下,采用针形电刀或5mm超声刀将直肠肿瘤完整切除(黏膜下或全层切除),手术创口在腔内连续缝合。结果31例直肠肿瘤均获完整切除,切缘均阴性。手术时间45~220min,平均95min;术中出血量0~180ml,平均40ml。手术并发症:暂时性排气失控2例,急性尿潴留1例,慢性阻塞性气道疾病急性发作1例,因服用阿斯匹林而出现继发性出血1例。术后病理分期:pT0期16例,pTis期2例,pT1期7例,pT2和pT3期各3例。31例随访2~92个月,平均23个月,肿瘤无原位复发。结论TEM是治疗直肠绒毛状腺瘤和早期直肠癌的一种安全、有效的微创手术方法。  相似文献   
60.
Objective of the study was to explore factors associated with early childhood obesity and assess whether having a foreign born mother is protective against childhood obesity. Data sources include 9 months and 4 years parent interviews and direct assessments of possessive children’s weight and height (4 years) or length (9 months) from the Early Childhood Longitudinal Study-Birth Cohort. Subjects were children with anthropometric measures who lived with their mothers (n = 9,700 at 9 months and 8,200 at 4 years). Overweight is defined as a weight-for-length ratio at or above the 95th percentile at 9 months; obesity is defined as a body mass index at or above the 95th percentile at 4 years. The prevalence of overweight/obesity was 15.4% at 9 months and 18.0% at 4 years. After adjustment for potential confounders, having a foreign-born mother was not associated with the odds of overweight at 9 months or 4 years. At 9 months and 4 years, low birth weight, pre-pregnancy weight and weight gain during pregnancy were protective of overweight. In addition to these factors, at 4 years, excessive weight gain in the first 9 months was the strongest predictors for obesity. Living in a safe neighborhood and ever having breastfed were protective against obesity. Having a foreign born mother is not protective of early childhood obesity. A focus on health of women prior to conception and on women’s and infants’ health in the perinatal period are key to addressing childhood obesity.  相似文献   
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