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51.
 In order to determine the dynamics of hematopoietic cell turnover, proliferative activity and incidence of apoptosis (programmed cell death) were evaluated in bone marrow trephine biopsies. Selection of patients (20 in each group) included in addition to a control group, idiopathic thrombocytopenia (ITP), reactive thrombocytosis (TH), secondary polycythemia-smokers' polyglobuly (PG), primary (essential-hemorrhagic) thrombocythemia (PTH), polycythemia vera (PV), and finally acute myeloid leukemia (AML). Apoptosis was demonstrated by the in situ end-labeling technique (ISEL) and proliferative activity by applying the monoclonal antibody PC10 raised against proliferating cell nuclear antigen (PCNA). To assess dynamic features of hematopoiesis, an index was calculated consisting of the ratio between PCNA-positive nuclei and the apoptotic cell fraction. This factor was termed the hematopoietic turnover index (HTI). Morphometric analysis revealed that the HTI was significantly increased in AML and PV. According to cell culture studies both disorders are characterized by either a prevalent proliferation of the myeloid or erythroid cell mass. On the other hand, PG, PTH, and TH showed no relevant enhancement of this index in comparison to the control specimen. In vitro experiment results are in keeping with the finding that PG and PTH are not associated with a significant expansion of the erythroid lineage (CFU-E). Similar to ITP and TH, in PTH megakaryocyte proliferation (CFU-MEG) is the predominant feature of cell turnover. Differences between PTH and TH are in line with the reduced in vitro formation of CFU-MEG in the latter disorder. In conclusion, our in situ study on turnover rates of the bone marrow in various neoplastic and reactive lesions extends previous experimental data on hematopoietic cell kinetics. Received: 10 March 1997 / Accepted: 18 May 1997  相似文献   
52.
A case of primary non-Hodgkin's lymphoma (NHL) of the mandible with unusual radiographic presentation is reported. The panoramic radiography revealed diffuse widening of the right mandibular canal with ill-defined margins and absence of edge sclerosis. Computed tomography showed infiltration of the superior portion of the canal with involvement of the vestibular cortex of the bone and of the alveolar ridge. Correspondence to: M. Bertolotto  相似文献   
53.
原发性肝癌栓塞化疗后血清AFP浓度与疗效关系的探讨   总被引:3,自引:0,他引:3  
目的 :分析 5 5例原发性肝癌经肝动脉插管栓塞化疗 (Transcatheterhepaticarterialchemo -embolization ,TAE)后血清AFP浓度与疗效的关系。方法 :通过动脉插管和血管造影 ,采用不同的化疗药物对肿瘤组织进行局部注入。用放射免疫法测定AFP浓度。结果 :TAE后血清AFP浓度降低与疗效有关 ,AFP≥ 4 0 0ng dl组有效率为 12 % ,AFP <10 0ng dl组有效率为 85 7%(P <0 0 1) ;TAE治疗后血清AFP浓度仍大于 4 0 0ng dl组癌肿转移率明显高于AFP <10 0ng dl组 ,而 2年生存率明显低于AFP <10 0ng dl组 (P <0 0 5和P <0 0 1)。结论 :TAE后血清AFP浓度的检测可反映肝癌介入治疗后疗效、预后及生存率  相似文献   
54.
急性心肌梗死再灌注期间的心电变化特征   总被引:1,自引:1,他引:0  
目的 探讨急性心肌梗死 (AMI)再灌注期间的心电变化特征。方法  46例经急诊冠状动脉造影明确为成功再灌注的AMI,其中 2 4例接受溶栓治疗和 2 2例接受直接经皮腔内冠状动脉成形 ,于发病的 6小时内以动态心电图技术持续2 4小时监测心电图变化 ,并与 1 5例无灌注者进行对比。结果 ①再灌注发生后 ,相应导联ST段迅速下降 ,约 2小时达较低水平 ;同时 ,T波正向振幅进行性降低 ,距再灌注 0~ 2 2 (2 7± 4 5)小时呈现T波倒置并逐渐加深。②再灌注后的 1小时内 ,室性心律失常明显增加 ,6~ 8小时后显著减少。结论 AMI早期再灌注发生后呈现特征性心电变化 ,及时识别这些特征将有助于临床评估再灌注状态和危险度分层  相似文献   
55.
From May 1970 to September 1983, 1714 children with different forms of primary tuberculosis were referred to the paediatric home care centre (Enfants soignés au Foyer, E.S.F.) of the Brussels University Hospital St.-Pierre. They were subdivided in five groups: asymptomatic (33%), symptomatic (28%), dubious tuberculous infections (35%), high-risk contacts (3%) and unestablished diagnosis (1%). They were aged from 10 days to 19 years, and 82% of them were migrants of low socio-economic level. Fifty percent of the symptomatic infections, mainly pulmonary, appeared in children under 3 years of age. An adult source of contamination was identified in 33% of the case (48% of the symptomatic children). Diagnosis was based on tuberculin screening with a 2IU intradermal test. Gastric aspirates yieldedMycobacterium tuberculosis in 15% of our patients, 11% of them showing resistance to one or more tuberculostatic drugs. Treatment was given to 1359 patients with excellent results. Therapy was shortened during the last 2 years of the study from 12 to 6 months for the asymptomatic patients and from 12 to 9 months for the symptomatic infections. Few complications were observed. Tuberculosis remains a serious cause of morbidity particularly in migrant children. Correct diagnosis and treatment of the disease is very important.  相似文献   
56.
Data on the effects of laser radiation on primary teeth are scarce. This study investigates the effects of exposing sound enamel, photo-initiated sound enamel, sound dentine and carious dentine of extracted primary teeth to a pulsed neodymium-yttrium aluminium garnet laser (Nd-YAG, wavelength 1.06 μm, pulse length 15μs). Each type of tissue was exposed to three fiuences. Qualitative and quantitative assessments of the irradiated areas revealed that the most marked changes were produced in carious dentine, followed in ranking order by sound dentine, photo-initiated enamel and sound enamel. Evidence of thermal damage to the hard tissues peripheral to the fibre-optic tip, and considerable inter-sample variation were found. The experimental evidence obtained in this in vitro study does not support the clinical use of pulsed laser at 1.06 μm wavelength for cutting primary enamel and dentine.  相似文献   
57.
创伤骨科中责任制护理初探   总被引:1,自引:0,他引:1  
本文复习了有关责任制护理的理论,从创伤骨科的角度,介绍了这一护理技术在创伤骨科中具体应用方法。通过对创伤骨科病人心理及临床特点的分析,提出了针对创伤病人的护理问题,订出护理计划,在阐述了责任制护理具体实施的优点时,对现存的问题也进行了分析,提出了改进措施。  相似文献   
58.
原发性色素性结节状肾上腺皮质病(附4例报告)   总被引:1,自引:0,他引:1  
目的:探讨原发性色素性结节状肾上腺皮质病(PPNAD)的临床表现和诊断治疗方法。方法:总结4例PPNAD的临床资料,4例均有库欣综合征的临床表现,内分泌检查结果提示为功能自主性肾上腺皮质肿瘤,但影像学检查并未发现肾上腺肿瘤。结果:4例患者均行单侧肾上腺全切除术,手术标本均表现为肾上腺大小正常或轻度增大,外表和切面上见黑色或深褐色小结节,结节间皮质萎缩,光镜下见组成结节的细胞体积大,脑质嗜伊红染色、颗粒状,部分细胞脑质中的颗粒状色素颗粒具脂褐质染色特征。结论:PPNAD在青少年中是一种引起库欣综合征的罕见病因,双侧肾上腺切除术是治愈本病的方法。  相似文献   
59.
急性左半结肠癌梗阻一期切除吻合治疗39例   总被引:1,自引:0,他引:1  
目的:探讨左半结肠癌致急性肠梗阻的手术处理方法。方法:回顾分析1995-2001年间39例左半结肠癌致肠梗阻一期切除吻合术的外科临床效果。结果:全组39例病人均采用梗阻近端肠管减压灌洗,并留置盲肠造瘘管术后接负压吸引,术后均一期愈合,未出现吻合口漏。随访2例中,1例存活率58%,3年存活率16%,5年存活率8%。结论:严格掌握手术适应症和基本操作,在病情允许时,对左半结肠癌急性肠梗阻行一期切除吻合手术是可行的。  相似文献   
60.
葛勇胜  许戈良 《医学综述》2007,13(19):1443-1445
肝移植已成为原发性肝癌治疗的一种重要选择。选择合适的肝癌病例作为移植对象是决定疗效及预后的关键,另外手术禁忌证及术后复发等问题也要慎重考虑。本文就肝癌肝移植治疗方面相关问题近年来的研究情况进行综述。  相似文献   
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