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581.
Leukemia of non-T lineage natural killer cells   总被引:2,自引:0,他引:2  
An unusual case of an aggressive leukemia of natural killer (NK) cells occurred in a 65-year-old male. Clinical characteristics of this case included hepatosplenomegaly, ascites, marrow infiltrate with leukemic cells, and a WBC up to 82.8 X 10(9) before therapy. One year before his presentation he had been noted to have a WBC of 12.1 X 10(9) with 78% lymphocytes, and 6 months before had noted intermittent fever and weight loss. He and his brother had well documented hereditary cold urticaria. The patient was treated with a modification of ProMACE CYTABOM regimen and had prompt regression of the leukemia with associated acute tumor lysis. Renal, hepatic, and marrow failure predominated during a terminal course that ended 22 days after therapy was commenced, and at autopsy there was no evidence for leukemic cell infiltrate in the liver, spleen or marrow. The leukemic cells were large granular lymphocytes by light and electron microscopic criteria, and had the following immunophenotype: CD2+, DR+, Leu7+, NKH1+, CD11+, CD3-, CD5-, CD4-, CD8-, CD16-. The cells displayed high antibody- dependent cell-mediated cytotoxicity (ADCC) and NK activity, and had a high rate of spontaneous proliferation in vitro that was not augmented by phytohemagglutinin (PHA), concanavalin A (Con A), or pokeweed mitogen (PWM). Southern analysis of DNA from leukemic cells revealed normal germline arrangements for the beta and gamma chains of the T cell antigen receptor and immunoglobulin heavy chain genes. The majority of metaphases were clonally abnormal revealing consistent rearrangements involving extra material attached to the long arms of chromosomes 5 and 11.  相似文献   
582.
583.
随着凋亡相关研究的进展,心肌细胞凋亡与心肌梗死(acute myocardial infarction,AMI)的关系逐渐受到重视.本实验联合应用粒细胞集落刺激因子(granulocyte-colony stimu-lating factor,G-CSF)和辛伐他汀动员干细胞修复AMI后的梗死心肌,通过流式及免疫组化法检测细胞凋亡率和BCL-2/BAX比值,评价其干细胞动员作用对梗死后心肌细胞凋亡的影响.  相似文献   
584.
Summary The aim of this study was to investigate whether cervical wear was associated with occlusal wear and clinical periodontal parameters in relatively older adults. A total of 30 patients, with multiple non‐carious cervical lesions (NCCLs) and without a disease or condition that could cause heavy tooth wear, were included in the study. The periodontal parameters including plaque index, probing pocket depth, gingival recession (GR) and tooth mobility were obtained from 641 teeth of which 475 (74·1%) displayed NCCLs. The levels of cervical wear and occlusal wear were determined according to a tooth wear index. Premolars were more likely to develop cervical wear than canines, molars and incisors. Cervical wear was significantly associated with less plaque accumulation and the presence of shallow pockets. The teeth with advanced GR and without increased mobility were 2·583 and 1·715 times more likely to develop deeper cervical lesions, respectively. Age and the level of occlusal wear were not linked to the bucco‐lingual depth of cervical wear. In conclusion, the significant association of advanced cervical wear with the relatively healthy periodontal status suggested the role of abrasion and its possible combined action with erosion in the aetiology of NCCLs. The rate of GR and the lack of tooth mobility could constitute predisposing factors for the progression of cervical wear because the exposed root surfaces could be more susceptible to abrasion and/or erosion, and the non‐mobile teeth resisting strongly against frictional forces, thus abrasive effects, could possibly develop cervical wear.  相似文献   
585.
586.
目的 检测慢性阻塞性胰腺炎小型猪血单核细胞趋化蛋白-1(MCP-1)含量及胰腺组织MCP-1蛋白表达,探讨其在胰腺纤维化中的作用.方法 采用不全结扎主胰管方法建立小型猪慢性阻塞性胰腺炎模型,术后4、6、8 周分批处死动物.观察胰腺病理变化;胶原(VG)染色评估胰腺纤维化程度;ELISA法检测血MCP-1浓度;免疫组化法检测胰腺组织MCP-1、α-SMA、PDGF、TGF-β1和NF-κB表达.结果 造模成功14头(58.3%).术后4周起胰腺体尾部呈萎缩性改变,间质纤维组织增生,炎细胞浸润,第8周改变最明显.胰腺纤维化Ⅰ期5头(35.7%),Ⅱ期4头(28.6%),Ⅲ期5头(35.7%).术后4、6、8周造模成功组血MCP-1含量分别为(102.44±36.25)pg/m1、(97.84±28.67)pg/ml、(94.32±28.42)pg/ml,显著高于对照组的(10.42±5.86)pg/ml、(8.58±4.86)pg/ml、(8.22±4.58)pg/ml(P值均<0.01).对照组胰腺无MCP-1蛋白表达,造模成功组胰腺组织内见MCP-1蛋白表达,且MCP-1表达与α-SMA、PDGF、TGF-β1和NF-κB表达呈正相关.结论 MCP-1在慢性阻塞性胰腺炎胰腺纤维化过程中起重要作用.  相似文献   
587.
ASL在中枢神经系统疾病诊断中的初步应用体会   总被引:3,自引:0,他引:3       下载免费PDF全文
目的:探讨动脉自旋标记(ASL)MRI灌注成像技术在中枢神经系统疾病中的临床价值.方法:24例颅内病变患者,其中急性脑梗死2例,脑血管畸形7例,胶质瘤4例,淋巴瘤2例,转移瘤4例,脑膜瘤5例.所有病例均经手术病理或随访证实.用ASL技术和动态磁敏感对比成像(DSC)2种方法进行MR灌注成像,分析2种方法对颅内病变的诊断价值.结果:对急性脑梗死患者可以显示灌注缺损区或低灌注区.在评价肿瘤血供方面,ASL与DSC 2种方法所测肿瘤组织rCBF值比较,差异无显著性意义.ASL技术磁敏感伪影明显小于DSC法,对于有出血、钙化的病灶以及颅底病变的显示明显优于DSC法,提高了定量分析的准确性.结论:ASL技术在评价脑组织局部血流灌注方面,具有可重复性高、完全非侵入性、不用注射对比剂等优点.同时对于有出血、钙化或位于颅底的病变,ASL技术明显优于DSC法.  相似文献   
588.
蒙药达日布-8是蒙医临床治疗高脂血症动脉粥样硬化的验方。目前,临床研究和实验研究都已证明达日布-8确有降低血脂、抗氧化及保护血管内皮等作用。并且具有疗效好、不良反应小等优势。高脂血症是“三高症”之一,具有患病率高、危害性大等特点,也是引起动脉粥样硬化的重要危险因素之一。而动脉粥样硬化是多种心血管疾病的主要病理变化,对人的生命健康极具有危害性。  相似文献   
589.
Background/aim To evaluate the incidence, clinical features, risk factors, and prognosis of central nervous system (CNS) involvement in patients with acute myeloid leukemia (AML).Materials and methodsAll AML patients who were admitted to Hacettepe University hospital between 2000 and 2021 were evaluated. The medical records of 548 AML cases were retrospectively analyzed. Results The frequency of CNS involvement was 2.4% (n = 13) at diagnosis and 4.6% (n = 25) at diagnosis or during follow-up. Parenchymal involvement was seen in 5 patients, leptomeningeal involvement was seen in 11 patients. Three patients had both leptomeningeal and parenchymal involvements, and 6 patients had optic nerve or ocular involvement. In univariate analysis, younger age and extramedullary involvement at diagnosis were associated with CNS disease at diagnosis, and extramedullary involvement at diagnosis was associated with CNS disease during follow-up. In multivariate analysis; younger age and extramedullary involvement at diagnosis were associated with CNS disease at diagnosis and during follow-up respectively. Median overall survival was 5.4 months in patients with CNS disease at diagnosis and 16.9 months in patients with CNS disease during follow-up and 16.2 months in patients with no CNS disease.Conclusion CNS disease is a rare complication of AML. Younger age and extramedullary involvement at diagnosis are risk factors for CNS involvement.  相似文献   
590.
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