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41.
Chronic myelocytic leukemia (CML) may display a lymphoproliferative phase (lymphoid blast crisis) that is generally of B cell phenotype. Since lymphoproliferative disorders may occur following bone marrow transplantation (BMT), it may be difficult to distinguish posttransplant relapse of CML lymphoid blast crisis from de novo lymphoproliferation. Lymphoid blast crisis cells from a patient with CML displayed immunoglobulin heavy chain gene (C mu) rearrangement before BMT. Following BMT the patient developed a lymphoproliferative disorder involving multiple organs. Clonal rearrangement of C mu was demonstrated in several involved tissues. The rearranged C mu restriction fragment was distinct from that displayed before BMT. Additionally, rearrangement of the breakpoint cluster region (bcr) was demonstrated in the pretransplant blast crisis sample, but not in the posttransplant lymphoproliferation samples, thus confirming that these lymphoproliferative disorders were distinct. Molecular genetic techniques offer powerful diagnostic tools for monitoring the course of patients with CML undergoing BMT.  相似文献   
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43.
The expression of adhesion molecules (alpha4beta1-integrin, LFA-1, ICAM-1) on T cells, measured by flow cytometry, was compared in different subtypes of multiple sclerosis (MS) and related to future lesion development as seen as delta T1 and T2 lesion load per year on magnetic resonance imaging (MRI). LFA-1 and alpha4beta1-integrin showed higher expression on CD4 and CD8 T lymphocytes in the secondary progressive compared to the relapsing-remitting (CD4: p<0.01, p=ns, p<0.05; CD8: p<0.001, p<0.001, p<0.001, respectively) and primary progressive MS phase (CD4: p<0.001, p<0.01, p<0.05; CD8: p<0.01, p<0.01, p<0.001, respectively). The adhesion molecule expression of alpha4- (r=0.31; p<0.05) and beta1-integrin (r=0.38; p<0.01) on CD4+ cells and of LFA-1beta on both CD4+ and CD8+ (r=0.28, p<0.05) and r=0.29; p<0.05, respectively) cells was significantly related to increase in T2 lesion load. Our study provides further evidence for the involvement of integrins in lesion development, shown as T2 lesions on MRI in MS.  相似文献   
44.
目的:观察糖尿病大鼠心肌缺血再灌注时血管紧张素Ⅱ、胰岛素样生长因子1、醛固酮、细胞间黏附分子1和自由基代谢的变化及L-精氨酸对其的影响。方法:实验于2005-02/2006-06在江苏大学医学院机能学实验室完成。①实验分组:腹腔注射链脲佐菌素制作糖尿病大鼠模型,30只大鼠造模成功。按随机数字表法分为3组(n=10):心肌缺血再灌注组:开胸结扎冠脉,造成心肌缺血,60min后放松再灌注60min;L-精氨酸治疗组:于手术前4周灌胃L-精氨酸250mg/(kg·d),然后重复心肌缺血再灌注组操作;假手术组:完成操作后只穿线不结扎,观察2h作为对照。实验结束时心室取血6mL,摘取心脏,留取左心室心肌组织。②实验评估:检测大鼠血浆血管紧张素Ⅱ、醛固酮和血清胰岛素样生长因子1含量及心肌细胞间黏附分子1蛋白表达。检测大鼠血清、心肌组织超氧化物歧化酶、谷胱甘肽-过氧化物酶活性、丙二醛含量及心肌线粒体Na ,K -ATP酶、Mg2 -ATP酶、Ca2 -ATP酶活性。结果:30只大鼠全部进入结果分析。①与假手术组相比,心肌缺血再灌注组血浆血管紧张素Ⅱ、醛固酮含量明显升高(P<0.05~0.01),血清胰岛素样生长因子1含量降低(P<0.05);L-精氨酸治疗4周后血浆血管紧张素Ⅱ、醛固酮含量低于心肌缺血再灌注组(P<0.05~0.01),血清胰岛素样生长因子1含量高于心肌缺血再灌注组(P<0.05)。②与假手术组相比,心肌缺血再灌注组血清、心肌丙二醛含量明显升高(P<0.05),血清、心肌超氧化物歧化酶和谷胱甘肽-过氧化物酶活性明显降低(P<0.05 ̄0.01);用L-精氨酸治疗4周后血清、心肌丙二醛含量低于心肌缺血再灌注组(P<0.05 ̄0.01),血清、心肌超氧化物歧化酶和谷胱甘肽-过氧化物酶活性高于心肌缺血再灌注组(P<0.05~0.01)。③与假手术组相比,心肌缺血再灌注组心肌线粒体Na ,K -ATP酶、Mg2 -ATP酶、Ca2 -ATP酶活性明显降低(P<0.05),心肌细胞间黏附分子1蛋白表达明显升高(P<0.01);用L-精氨酸治疗4周后心肌线粒体Na ,K -ATP酶、Mg2 -ATP酶、Ca2 -ATP酶活性明显高于心肌缺血再灌注组(P<0.05),心肌细胞间黏附分子1蛋白表达低于心肌缺血再灌注组(P<0.05)。结论:血管紧张素Ⅱ、醛固酮和胰岛素样生长因子1可能共同参与了糖尿病心肌缺血再灌注的发生,细胞间黏附分子1蛋白表达与糖尿病心肌损伤关系密切。L-精氨酸通过减少细胞间黏附分子1蛋白表达,起心肌保护作用。糖尿病心肌缺血再灌注时存在自由基代谢异常,补充L-精氨酸后,可通过提高超氧化物歧化酶、谷胱甘肽-过氧化物酶和ATP酶活性,降低丙二醛水平,减轻自由基损伤,改善心肌组织功能。  相似文献   
45.
目的:对广东地区散发克罗恩病患者β防御素2启动子区基因突变进行筛查,探讨该基因在克罗恩病发病中的作用。方法:克罗恩病组为2002-01/2006-10于南方医院消化科确诊的克罗恩病患者45例,对照组为门诊健康志愿者50例。签定知情同意书后分别取静脉血5mL,提取基因组DNA,并根据设计好的引物序列及PCR反应条件进行目的片段的扩增,阴性对照使用蒸馏水代替DNA。扩增成功的目的基因片段用DNA纯化试剂盒进行纯化,并由上海英俊公司完成测序工作。利用DNAMAN软件将患者测序结果与正常对照结果进行比对,并与基因库数据对照(http://www.ncbi.nlm.nih.gov/BLAST/),SPSS13.0进行统计学分析。并根据结果分析其与克罗恩病患者病变特点的相关性。结果:①纳入的45例克罗恩病患者与50例健康志愿者在性别和年龄上无统计学意义,并全部进入实验分析。②45例克罗恩病患者中有4例在β防御素2启动子区第-233(G→C)位发现基因突变,密码子由AGG变成AGC,编码氨基酸由精氨酸变成丝氨酸,而50例对照组未发现此改变,二者比较具有统计学意义(χ2=4.34,P<0.05)。③4例突变的患者病变均位于小肠(χ2=10.81,P<0.01)且病情较重。结论:在克罗恩患者中存在着β防御素2启动子区基因突变携带者,与患者发病年龄、病变部位、病变程度明显相关,有必要对其功能进行进一步探讨。  相似文献   
46.
47.

Background  

Whole body vibration (WBV) exposure at work is common and studies found evidence that this exposure might cause low back pain (LBP). A recent review concluded there is a lack of evidence of effective strategies to reduce WBV exposure. Most research in this field is focussed on the technical implications, although changing behaviour towards WBV exposure might be promising as well. Therefore, we developed an intervention programme to reduce WBV exposure in a population of drivers with the emphasis on a change in behaviour of driver and employer. The hypothesis is that an effective reduction in WBV exposure, in time, will lead to a reduction in LBP as WBV exposure is a proxy for an increased risk of LBP.  相似文献   
48.
Baars BJ 《Toxicology letters》2002,128(1-3):55-68
In December 1999 the oil tanker 'Erika', carrying approximately 30 tons of heavy fuel oil, wrecked before the coast of Brittany (France), polluting the local beaches and rocks over a distance of some 500 km. Also numerous birds were affected. During the first months of 2000 the coastal area and many birds were cleaned. The health risk for people involved in these cleaning activities and for tourists was evaluated with emphasis on the carcinogenic properties of this oil. The outcome indicates that the risks were limited to people who had been in bare-handed contact with the oil. Firstly they had an increased risk for developing skin irritation and dermatitis, however, these effects are in general reversible. Secondly they had an increased risk for developing skin tumours, but since the dermal contacts with the oil were of relative short duration, this risk is considered to be very limited.  相似文献   
49.
Arsenic in drinking water is a worldwide health problem that is associated with cardiovascular disease, but the cause is currently unknown. In order to examine whether arsenic affects vasomotor tone in blood vessels, we investigated the effect of arsenic on agonist-induced vasorelaxation and vasoconstriction using the isolated rat aortic rings in in vitro organ bath system.  相似文献   
50.
BACKGROUND: Operative complications after laparoscopic cholecystectomy (LC) vary. Abdominal pain and other symptoms caused by fluid accumulation in the operative area are not uncommon. Cystic duct (CD) leakage is one of the main sources of the fluid. This study was to evaluate the procedures used in the diagnosis and management of CD leakage after LC. METHOD: The clinical materials of 3 patients with CD leakage after LC were studied retrospectively.  相似文献   
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