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991.
Aims/hypothesis To test the hypothesis that adipose tissue lipolysis is enhanced in patients with Type 2 diabetes mellitus, we examined the effect of exercise on regional adipose tissue lipolysis and fatty acid mobilisation and measured the acute effects of exercise on the co-ordination of adipose tissue and splanchnic lipid metabolism.Methods Abdominal, subcutaneous adipose tissue and splanchnic lipid metabolism were studied by conducting measurements of arterio-venous concentrations and regional blood flow in six overweight Type 2 diabetic subjects before, during and after exercise.Results Exercise induced an increase in adipose tissue lipolysis and fatty acid release. However, the increase in adipose tissue blood flow was small, limiting fatty acid mobilisation from this tissue. Some of the fatty acids were released in excess in the post-exercise phase. The splanchnic fatty acid uptake was unchanged during the experiment but splanchnic ketogenesis increased in the post-exercise phase. The arterial glucose concentration decreased during exercise and continued to decrease afterwards, indicating an imbalance between splanchnic glucose production and whole-body glucose utilisation.Conclusions/interpretation Regional subcutaneous, abdominal adipose tissue lipolysis is no higher in patients with Type 2 diabetes than in young, healthy subjects. Exercise stimulates adipose tissue lipolysis, but due to an insufficient increase in blood flow, a high fraction of the fatty acids liberated by lipolysis cannot be released to the blood. Splanchnic glucose release is smaller than whole-body glucose utilisation during exercise and post-exercise recovery.Abbreviations ICG indocyanine green - 3-OHB 3-hydroxybutyrate - TAG triacylglycerol - VO2,max peak oxygen consumption  相似文献   
992.
CD38 expression on chronic lymphocytic leukaemia (CLL) cells is a poor prognostic factor, however, methods for measuring this vary. The QuantiBRITETM flow cytometry (FC) system yields an absolute antigen expression value (antibodies bound/cell, ABC) and may be useful in standardizing CD38 expression analysis. We evaluated cryopreserved pretreatment CLL cells for CD20 ABC, CD38 ABC, and percentage of CD38+ B cells from 131 patients requiring therapy. The 92 patients (70%) with >/= 100 CD38 ABC had worse overall survival (OS; 34% at 5 years) compared with those with < 100 CD38 ABC (70% at 5 years, mortality hazard ratio 2.30, 95% confidence interval 1.28-4.12; two-tailed P = 0.003). Among the 64 patients with < 30% CD38+ cells, OS of the 25 with >/= 100 ABC was worse than that of the 39 with < 100 ABC (P = 0.018). OS of patients with < 30% CD38+ cells and >/= 100 ABC was actually similar to that of patients with >/= 30% CD38+ cells. BrightCD20 expression (>/= 20 000 ABC) was not associated with a worse OS (P = 0.10). The presence of >/= 100 CD38 ABC in CLL patients requiring therapy is an unfavourable prognostic factor for OS and quantitative FC may be superior to percentage CD38+ cell assessment. Prospective trials are required to determine more precisely the prognostic significance of absolute expression levels in fresh CLL cells.  相似文献   
993.
目的 分析脂联素 (ADIPO)与机体脂肪含量、分布及组织胰岛素敏感性 (IS)的关系。 方法 符合 1999年WHO糖尿病诊断标准的 2型糖尿病 (T2DM )患者 4 0例 ,男 16例 ,女 2 4例 ,平均年龄 (5 5± 7)岁 ,体质指数 (BMI) (2 5 0± 2 5 )kg/m2 ,病程 (3± 4 )年。测定常规临床检查项目和血糖、血浆胰岛素水平。按HOMA模型计算胰岛素抵抗 (IR)指数。其中 2 0例患者应用正常血糖高胰岛素钳夹试验测定组织葡萄糖代谢率 (M)。同时测定ADIPO、肿瘤坏死因子α(TNFα)和游离脂肪酸(FFA)水平。应用双能X线测定机体的全身脂肪含量、全身瘦肉组织含量 ,并计算全身脂肪含量百分比。其中 17例患者同时应用核磁共振测定脂肪分布 ,以电子计算机计算腹内脂肪面积 (VFA)、腹部皮下脂肪面积 (SFA) ,并计算VFA/SFA比值。 结果  (1)肥胖或体脂含量增加的T2DM患者其血浆ADIPO显著降低 ;(2 )腰围或腹内脂肪增加的T2DM患者其血浆ADIPO显著降低 ;(3)T2DM患者ADIPO水平与M值显著正相关 ,与TNFα、FFA呈显著负相关。 结论 T2DM患者体脂含量和分布影响血浆ADIPO水平 ,ADIPO与IS呈显著正相关。  相似文献   
994.
We report a case, which we believe to be rare, of adenosine-sensitive atrial tachycardia (AT) originating from the mitral valve annulus. The patient, a 73-year-old woman, died of unrelated cause 4 years after radiofrequency (RF) ablation therapy. Histologically, fibrous replacement of atrial musculature by mature collagenous tissue produced by the RF current was observed at the left inferior atrioventricular junction. In serial sections that included the coronary sinus, two distinct nodal structures containing small, pale myocytes within the fibrous tissue matrix were identified around the region of the ablation lesion. Our case appears to be a unique representation of tissue that was associated with the occurrence and maintenance of AT.  相似文献   
995.
Reprogramming cells for transplantation   总被引:1,自引:0,他引:1  
The field of tissue engineering, involving the reprogramming of stem cells or rejuvenation of specific differentiated cells, is emerging as a promising strategy to repair the damaged myocardium. The eventual goal is to be able to take a patient's own cells, expand them ex vivo, genetically engineer them to enhance specific properties, and then reintroduce them into the patient's heart to create a replacement tissue. Our review paper describes data that supports the potential of this strategy. This clinically relevant, combined strategy of genetic and tissue engineering could be of importance in treating elderly patients with massive myocardial damage, patients whose normal myogenic or angiogenic cells have been depleted or are inadequate in their growth potential, to prevent LV deterioration and heart failure.  相似文献   
996.
997.
Summary Although careful measurement of the size of capillary loops is mandatory in the evaluation of diabetic microangiopathy, no current technique allows rapid and careful morphometric analysis of capillaroscopic findings. In an attempt to solve this problem, assembling readily available instruments, the authors have set up an original apparatus for computed videomicroscopy. The apparatus ensures detailed morphological assessment of single loops at high magnification. Each single frame stored on videocassettes can be digitalized for morphometric analysis, saved on floppy disk or printed by means of a graphic printer.  相似文献   
998.
声触诊组织成像量化技术评估正常人群冈上肌腱弹性变化   总被引:1,自引:1,他引:0  
目的 探讨声触诊组织成像量化技术(VTIQ)评估正常人冈上肌腱弹性变化的价值。方法 对120名健康志愿者行二维超声及VTIQ检查,根据年龄将其分为组1(20~39岁)、组2(40~59岁)及组3(≥ 60岁)。测量冈上肌腱最大厚度及其浅层、深层剪切波速度(SWV),比较不同性别、年龄组及优势手与非优势手侧冈上肌腱厚度及浅层与深层SWV值的差异。结果 同一性别内优势手侧与非优势手侧、不同性别间非优势手侧及优势手侧冈上肌腱厚度值差异均无统计学意义(P均>0.05)。3组间优势手侧及非优势手侧冈上肌腱厚度值差异均有统计学意义(P均<0.05);组3优势手侧及非优势手侧冈上肌腱厚度均大于组1及组2(P均<0.05),组1与组2差异均无统计学意义(P均>0.05)。3组组内优势手侧与非优势手侧冈上肌腱厚度值差异均无统计学意义(P均>0.05)。3组间优势手侧及非优势手侧冈上肌腱浅层、深层SWV值差异均有统计学意义(P均<0.001);3组组内优势手侧冈上肌腱浅层、深层SWV值与非优势手侧差异均无统计学意义(P均>0.05),但优势手侧及非优势手侧冈上肌腱深层SWV值大于浅层(P均<0.05)。组3男性冈上肌腱浅层及深层SWV均高于女性(P均<0.05),其余2组差异均无统计学意义(P均>0.05)。结论 肌腱退行性变时,不仅在形态学上表现为厚度增加,在力学特征上还可表现为肌腱软化。VTIQ可间接评价冈上肌腱弹性变化。  相似文献   
999.
目的探讨和研究氯吡格雷联合溶栓治疗急性心肌梗死的临床疗效。方法选取2012年1月—2013年5月之间该院收治的50例急性心肌梗死患者作为研究对象,根据入院编号进行随机分组,分为观察组和对照组,各25例,对照组单纯采用重组人组织型纤溶酶原激酶衍生物进行溶栓治疗,观察组患者则在溶栓治疗基础上加用氯吡格雷联合治疗,对比两组患者的疗效及心肌酶谱变化。结果观察组患者总有效率92.0%,显著高于对照组患者的76.0%,差异有统计学意义(P<0.05);治疗前两组患者的肌酸激酶、肌酸激酶同工酶对比差异无统计学意义,治疗后观察组显著低于对照组,差异有统计学意义(P<0.05)。结论氯吡格雷联合溶栓治疗急性心肌梗死的疗效确切,相较于单纯溶栓治疗更具优势,能够有效降低心肌酶水平,提高疗效,值得在临床上推广和应用。  相似文献   
1000.
目的建立针对扎伊尔型(ZEBOV)及苏丹型埃博拉病毒(SEBOV)特异、灵敏和快速的Taq Man探针实时定量PCR核酸检测方法。方法选用世界卫生组织(WHO)参比实验室所使用的引物和探针序列,建立针对扎伊尔型及苏丹型埃博拉病毒的NP基因序列保守区的Taq Man探针实时定量PCR核酸检测方法,验证检测方法的灵敏性、特异性和稳定性,并与常规PCR检测方法进行比较。结果所建立的实时定量PCR方法可用于ZEBOV及SEBOV的特异性检测,较传统PCR方法反应快捷、灵敏,分别可达:ZEBOV 34拷贝/反应、SEBOV 24拷贝/反应;具有良好的特异性、稳定性和可重复性。结论建立了ZEBOV及SEBOV Taq Man探针实时定量PCR核酸检测方法,该方法可有望用于埃博拉病毒(EBOV)的实验室、临床及现场核酸检测。  相似文献   
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