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Summary Comparison of clinical data of 64 patients with centroblastic lymphoma, 55 patients with immunoblastic lymphoma and 31 patients with lymphoblastic lymphoma not only confirmed the original assumption of high-grade malignancy as proposed by the concept of the Kiel classification but also demonstrated distinct clinical differences, particularly between lymphoblastic lymphoma and the two other entities. Rapid lymph node enlargement as well as steep fall of survival curves within the first year after diagnosis were common characteristics. Bimodal age distribution, predominance of males and early generalization of disease were typical features of lymphoblastic lymphoma; elderly patients and patients with the unclassified subtypes of lymphoblastic lymphoma exhibited the worst prognosis. Whereas patients with centroblastic and immunoblastic lymphomas showed similar distribution of age, sex and initial stage of disease, patients with immunoblastic lymphoma presented more frequently with a reduced performance status and showed a poorer response to radio- and chemotherapy resulting in a worse prognosis discernible after the first year of follow-up. Generalization during course of the disease was significantly more frequent in immunoblastic than in centroblastic lymphoma.Supported by the Deutsche Krebshilfe e. V., BonnPresented in part at the 5th Meeting of the International Society of Haematology, European and African Division, Hamburg, August 26–31, 1979  相似文献   
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目的了解安徽、湖南、江苏省结核分支杆菌的基因型状况及其分子流行病学规律。方法以结核分枝杆菌插入序列IS6110序列为模板,设计一对特异外向引物,建立一种结核分枝杆菌的快速分子生物学分型方法——IS6110PCR分型方法,进行三省结核病分子流行病学研究。结果根据IS6110PCR指纹图谱,191株安徽、湖南和江苏三省的结核分枝杆菌菌株可被分成6个主要的基因型(Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ和Ⅵ),江苏省的主要基因型为I和V型,安徽省的主要基因型为III型,湖南省的主要基因型为I和II型,V型菌株全部为江苏省菌株,IV型菌株全部为湖南省菌株。结论三省之间结核分支杆菌的基因型存在明显的差异,各自存在着独立的流行菌型,其真实原因有待进一步研究。  相似文献   
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Introduction: Recent in vitro studies suggest that CAPN3 deficiency leads initially to accelerated myofiber formation followed by depletion of satellite cells (SC). In normal muscle, up‐regulation of miR‐1 and miR‐206 facilitates transition from proliferating SCs to differentiating myogenic progenitors. Methods: We examined the histopathological stages, Pax7 SC content, and muscle‐specific microRNA expression in biopsy specimens from well‐characterized LGMD 2A patients to gain insight into disease pathogenesis. Results: Three distinct stages of pathological changes were identified that represented the continuum of the dystrophic process from prominent inflammation with necrosis and regeneration to prominent fibrosis, which correlated with age and disease duration. Pax7‐positive SCs were highest in the fibrotic group and correlated with down‐regulation of miR‐1, miR‐133a, and miR‐206. Conclusions: These observations, and other published reports, are consistent with microRNA dysregulation leading to inability of Pax7‐positive SCs to transit from proliferation to differentiation. This results in impaired regeneration and fibrosis. Muscle Nerve 47: 731–739, 2013  相似文献   
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The etiology of cerebral small vessel disease (CSVD) is the subject of ongoing research. Although intracranial atherosclerosis (ICAS) has been proposed as a possible cause, studies on their relationship remain sparse. We used 7 T vessel wall magnetic resonance imaging (MRI) to study the association between intracranial vessel wall lesions—a neuroimaging marker of ICAS—and MRI features of CSVD. Within the SMART-MR study, cross-sectional analyses were performed in 130 patients (68 ± 9 years; 88% male). ICAS burden—defined as the number of vessel wall lesions—was determined on 7 T vessel wall MRI. CSVD features were determined on 1.5 T and 7 T MRI. Associations between ICAS burden and CSVD features were estimated with linear or modified Poisson regression, adjusted for age, sex, vascular risk factors, and medication use. In 125 patients, ≥1 vessel wall lesions were found (mean 8.5 ± 5.7 lesions). ICAS burden (per + 1 SD) was associated with presence of large subcortical and/or cortical infarcts (RR = 1.65; 95%CI: 1.12–2.43), lacunes (RR = 1.45; 95% CI: 1.14–1.86), cortical microinfarcts (RR = 1.48; 95%CI: 1.13–1.94), and total white matter hyperintensity volume (b = 0.24; 95%CI: 0.02–0.46). Concluding, patients with a higher ICAS burden had more CSVD features, although no evidence of co-location was observed. Further longitudinal studies are required to determine if ICAS precedes development of CSVD.  相似文献   
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Background

Determination of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status is standard for predicting prognosis and determining treatment options for patients with breast cancer. In 2010, the American Society of Clinical Oncology (ASCO) and College of American Pathologists (CAP) issued guidelines that tumors with ≥1 % positively staining cells should be considered ER positive. Here, we determined how this cutoff relates to molecular subtype.

Methods

Clinicopathological characteristics were compared between ER-negative, ER-positive, and low-ER-staining (1–10 %) tumors using chi-square analysis with P < 0.05 defining statistical significance. Gene expression data were generated for 26 low-ER-staining tumors, and their intrinsic subtype determined. Immunohistochemistry (IHC)-defined surrogate subtypes, using the threshold of positivity defined by ASCO/CAP guidelines, were compared with molecular subtypes.

Results

Low-ER-staining tumors were clinicopathologically more similar to ER-negative than to ER-positive tumors; 88 % of low-staining tumors were basal like or HER2 enriched. Only those tumors expressing 10 % ER-positive cells were classified as luminal A subtype.

Conclusions

Under ASCO/CAP guidelines, tumors with 1–10 % ER staining would be classified as ER positive, yet most are basal like or HER2 enriched and have pathological features similar to ER-negative tumors. Clinical trials seeking to treat tumors of ER-negative basal-like and/or HER2-enriched subtypes should thus not preclude enrollment based solely on results of ER immunohistochemistry. As ER status is a critical element in the choice of treatments for patients with breast cancer, it is imperative that the most effective method for classifying tumors be developed.  相似文献   
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