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11.
Granulocytic sarcoma is an uncommon extraskeletal tumor most frequently associated with leukemia. We present a case of bone
location with unusual pattern in a patient with no evidence of myeloproliferative disorder at presentation or follow-up. 相似文献
12.
Fritz Schick Hermann Einsele Renate Kost Stephan Duda Wulf-Ingo Jung Otto Lutz Claus D. Claussen 《Journal of magnetic resonance imaging : JMRI》1994,4(1):71-78
Magnetic resonance (MR) studies were performed in 14 patients as early as possible (21–110 days) after bone marrow transplantation (BMT). MR characteristics of lumbar vertebral bone marrow were studied with T1-weighted spin-echo imaging, water- and fatselective imaging with a frequency-selective excitation technique, and point-resolved spatially localized proton spectroscopy. Signals from water and fat protons and their T1 and T2 values were analyzed. Water proton signal intensity correlated well with cellularity within bone marrow, as determined with parallel iliac crest biopsies. The fraction of signal from water in red bone marrow of patients with allogeneic transplants from siblings (four cases) was significantly higher than in four patients with autologous transplants. The latter showed very low cellularity in the period of about 4 weeks after BMT because of the cytotoxic pretreatment of the bone marrow. The MR results in six patients with allogeneic transplants from unrelated donors ranged widely, depending on the complications after BMT. Analysis of data obtained with the different techniques showed that water- and fat-selective MR imaging and spectroscopic methods are useful for noninvasive monitoring of hematopoietic reconstitution after BMT. 相似文献
13.
实时荧光定量PCR检测PML-RARα融合基因的临床应用研究 总被引:1,自引:0,他引:1
目的 利用PML-RARα融合基因作为标志物,应用实时荧光定量PCR技术,监测急性早幼粒细胞白血病(APL)微小残留病(minimal residual disease,MRD)患者体内病毒的状态,探讨预测APL复发风险的方法.方法 利用本实验室建立的定量检测APL患者PML-RARα融合基因的方法,对25例处于初诊、完全缓解(complete remission,CR)、复发等不同阶段的APL患者进行了PML-RARα融合基因的定量检测,并对其中6例患者的MRD状态进行了动态监测.结果 应用荧光定量PCR技术分析患者初诊、CR和复发状态的PML-RARα基因对数值(lg)水平,结果 显示有统计学意义(x2=6.847,P<0.05);随访期患者的PML-RARα对数值(lg)水平变化较大:初诊时较高(-0.61±0.79),CR时下降(-1.31±0.62),复发时又出现上升(-0.57±0.44),提示若该患者在CR时的对数值呈现上升趋势,患者复发的机率大.结论 应用实时荧光定量(RQ)-PCR技术定量检测PML-RARα融合基因,对监测APL患者MRD状态具有临床适用性,随访期的MRD动态追踪监测具有预后价值. 相似文献
14.
Exposure of murine erythroleukemia cells (MELCs) to nicotinamide (NA) or its synthetic analog N′-methylnicotinamide (N′-MN) reduces cell growth and induces terminal differentiation, marked by increased heme and globin accumulation. On the contrary, 1-methylnicotinamide (1-MN), the primary metabolite of excess NA, was found to stimulate cell growth and reduce spontaneous differentiation of cultured MELCs. Log phase MELCs exhibited up to 50% higher cell density above untreated cells when cultured for up to 96 h with 2.5 mM 1-MN. When combined with NA or several chemically-unrelated inducers of hemoglobin synthesis in cultured MELCs, 1-MN reduced the globin mRNA levels and heme accumulation by 40–80%. 1-MN was able to inhibit heme production if present during only the first 24–48 h after NA exposure. Pre-treatment with 1-MN could not confer resistance of cells to effects of NA, suggesting the inhibition is reversible. Commitment to differentiate in semisolid medium by the most potent inducer, 5 mM N′-MN, was inhibited up to 95% by 2.5 mM concentrations of 1-MN. It appears that 1-MN has opposing effects on growth and induction of differentiation than those seen in MELC cultures exposed to NA or N′-MN. 相似文献
15.
16.
Matthias Bollow Wolfgang Knauf Agnieszka Korfel Matthias Taupitz Andreas Schilling Karl-Jürgen Wolf Bernd Hamm 《Journal of magnetic resonance imaging : JMRI》1997,7(1):241-250
The purpose of this study was (a) evaluation of dynamic contrast-enhanced MR imaging of normal bone marrow versus malignant bone marrow infiltrations in patients with proven B-cell-type chronic lymphocytic leukemia (B-CLL) and (b) correlation with the clinical stage according to Binet (stages A, B, C) and response to therapy. Bone marrow imaging of the lumbar spine, pelvis, and proximal femurs was performed at 1.5 T in 45 patients without known malignancy and in 30 patients with B-CLL. The differences between opposed-phase and in-phase dynamic gradient-echo sequences before and up to 10 minutes after intravenous application of .1 mmol/kg body weight of gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA) were evaluated in normal bone marrow. The contrast-enhancement patterns of normal and malignant bone marrow were compared using the opposed-phase dynamic gradient-echo sequence. Ten of the patients with bone marrow infiltrations (Binet stage C) additionally underwent MR imaging follow-up during therapy. Opposed-phase gradient echo sequences demonstrated a signal decrease of normal bone marrow, and in-phase gradient echo sequences demonstrated a signal increase of normal bone marrow after administration of Gd-DTPA. The dynamic signal intensity time courses differed significantly (P < .05) between Binet stages B and C and controls as well as among the three Binet stages of B-CLL. In the 10 patients followed during therapy, MR imaging sensitively demonstrated response (n = 6), nonresponse (n = 2), or relapse after initial response (n = 2). In out-of-phase imaging, both normal bone marrow and initial bone marrow infiltration in CLL stage Binet A show signal decrease after administration of contrast agent, whereas there is increase in signal intensity in higher-grade bone marrow infiltration in Binet stage B or C disease. The signal loss of normal bone marrow in out-of-phase imaging is a phase effect rather than a T2* effect. The differentiation of initial from higher-grade bone marrow infiltration on out-of-phase images relies solely on a shift in the fat/water ratio. 相似文献
17.
全反式维甲酸治疗急性早幼粒细胞白血病期间D-二聚体测定的临床意义 总被引:1,自引:0,他引:1
目的 探讨在全反式维甲酸 (ATRA)治疗急性早幼粒细胞白血病 (APL)前后弥漫性血管内凝血(DIC)发生率与D 二聚体含量的关系及意义。方法 应用ELISA法检测 30例APL患者 (包括 12例合并DIC患者 )发病时及应用ATRA治疗后D 二聚体水平的变化 ,并与正常对照组比较。结果 30例APL患者治疗前血浆D 二聚体水平 (2 .38± 0 .98mg/L)较正常对照组 (0 .2 5± 0 .0 9mg/L)明显升高 (P <0 .0 1) ,其中 12例并发DIC者(2 .5 2± 0 .12mg/L)明显高于 18例不并发DIC者 (2 .18± 0 .96mg/L)。结论 APL患者D 二聚体检测值随维甲酸治疗逐渐降低 ,并可预测ATRA治疗过程中DIC变化及预后。 相似文献
18.
选择分别位于bcr/abl嵌合基因的Mbcrl第二外显子和abl的第二外显子上的两条引物,对18例慢粒白血病及2例急淋白血病标本进行逆转录PCR(RT-PCR)检测。结果:在18例包括ph(+)和ph(-)不同病期的慢粒白血病患者血中均检出bcr/abl嵌合基因的表达,其中14例为K-28型表达,1例为L-6型表达,3例为K-28型,L-6型同时表达;2例急淋白血病标本中1例为K-28型表达。研究结果表明,1.bcr/abl嵌合基因是慢粒白血病的一个重要分子生物学特征;2.ph(+)和ph(-)慢粒白血病的分子生物学基础相同,即均有bcr/abl嵌合基因;3.至少部分急淋白血病与慢粒白血病有相同的分子生物学基础;4.bcr的断裂点位置可能有一定的临床意义,但有待进一步研究;5.同时表达L-6型和K-28型的情况多见于急变区,此现象提示体内可能同时有两类不同嵌合的白血病细胞或白血病急变期bcr出现新的重排。 相似文献
19.
慢性粒细胞白血病100例骨髓组织病理学Hannover分类法意义探讨 总被引:2,自引:0,他引:2
本文对100例慢性粒细胞白血病(CML)患者进行组织病理学研究,应用Hannover国际分类法进行分类,观察到骨髓组织病理学中巨核细胞增多者临床症状较重,中位生存时间较短,认为该分类法对临床及预后判断有指导意义,比既往应用的Bartl及Frisch分类法优越。 相似文献
20.
采用20~200U/ml的重组人肿瘤坏死因子(rhTNF-α)处理体外液相培养的人早幼粒白血病细胞珠HL-60,观察到50~200U/ml的小剂量TNF具有诱导其向单核-巨噬细胞途径分化及抑制其增殖的效应。采用细胞总RNA打点杂交技术检测1~100U/mlTNF诱导HL-60细胞早期(12小时内)对其c-myc,c-fos原癌基因表达的影响,发现TNF可抑制c-mycmRNA水平及c-fos短暂性表达增高。结果表明此小剂量rhTNF-α具有诱导白血病细胞分化的效应及调控多癌基因表达的作用。 相似文献