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81.
目的:探讨血浆心钠素(ANP)、脑利钠肽(BNP)、C型利钠肽(CNP)在2型糖尿病血管病变时的变化及其临床意义。方法:应用酶联免疫吸附法(ELISA)测定正常对照组(9例)、2型糖尿病无血管病变组(34例)及2型糖尿病血管病变组(23例)血浆proANP、BNP fragment及NT-proCNP浓度,分析各组间血浆利钠肽水平的变化及相关因素。结果:2型糖尿病血管病变组血浆ANP、BNP明显高于另外2组(P<0.01),而血浆CNP明显降低(P<0.01),2型糖尿病血管病变组各亚组(微血管病变组、大血管病变组及微血管合并大血管病变组)间血浆利钠肽水平无明显差异(P>0.05)。2型糖尿病血管病变组血浆ANP与BNP间存在显著正相关(r=0.309, P<0.05),ANP与CNP(r=-0.374, P<0.05)以及BNP与CNP(r=-0.653, P<0.01)间存在显著负相关。结论:血浆ANP、BNP及CNP的联合检测可以作为简便、价廉、可靠的糖尿病血管病变的筛选指标。  相似文献   
82.
83.
目的 在"创而床准备(WBP)"理论指导下,观察负压封闭吸引局部处理糖尿病溃疡的疗效.方法 收集2000年1月至2005年1月间收治的27例糖尿病溃疡患者作对照组,2005年1月至2007年6月的8例糖尿病溃疡患者为试验组.两组患者均经常规系统的治疗,试验组在创面的黑、黄期采用清创后负压吸引治疗.观察两组创而各分期间的演进情况.比较两组手术Ⅰ期修复率、入院首次及实施负压治疗后1、2、3周创面细菌学检查结果 .观察各期创面组织标本的HE染色和黄、红两期Ⅰ、Ⅲ型胶原纤维苦味酸-天狼猩红染色结果 及对其含量进行图像分析.结果 试验组患者创面各分期的演进速度、于术Ⅰ期修复率均优于以照组(100%比46%,P<0.05).治疗2周后试验组创面末检出致病菌,对照组检出率为66.7%(P<0.05).HE染色显示试验组各期间的演进类似于急性创面愈合过程,且试验组黄期Ⅰ、m型胶原总含量为12.28%,对照组为24.77%(P<0.01).结论 基于WBP方案的负压吸引治疗能促进糖尿病溃疡的创面愈合过程.  相似文献   
84.
Summary The pathogenesis of the diabetic glomerular lesion is unknown. However, cumulative indirect evidence favors hemodynamic factors associated with the abnormal endocrine environment as the cause of diabetic angiopathy. Experimental evidence suggests that the increased hydrostatic pressures in capillary beds, a hallmark of the early stages of insulin-dependent diabetes, are associated with macromolecular leakage leading to the typical thickening of glomerular capillary basement membrane and increased glomerular mesangial matrix even prior to the occurrence of systemic hypertension. Patients with renal or carotid artery stenosis seem to be protected against diabetic nephropathy and retinopathy on the stenosed side. The first signal of diabetic nephropathy even before deterioration of the renal function is microalbuminuria detected by sensitive methods such as radioimmunoassay. Not only in hypertensive, but even in normotensive diabetic patients with microalbuminuria antihypertensive therapy has been shown to reduce albumin excretion rate and to slow the progression of diabetic nephropathy. Once overt diabetic nephropathy has been established, hypertension is a constant accompaniment of the disease. Thus, hypertension may be a cause as well as a result of diabetic nephropathy. Tight control of blood sugar in close association with antihypertensive treatment reducing blood pressure to a lower normal limit, possibly with agents that specifically decrease glomerular capillary hydraulic pressure are the corner stone in protection against progression of the diabetic angiopathy.Abbreviations ECF extracellular fluid - ESRD end-stage renal disease  相似文献   
85.

Objectives

Rigorous visual evidence on whether or not biofilms are involved in diabetic foot osteomyelitis (DFO) is lacking. We employed a suite of molecular and microscopic approaches to investigate the microbiome, and phenotypic state of microorganisms involved in DFO.

Methods

In 20 consecutive subjects with suspected DFO, we collected intraoperative bone specimens. To explore the microbial diversity present in infected bone we performed next generation DNA sequencing. We used scanning electron microscopy (SEM) and peptide nucleic acid fluorescent in situ hybridization (PNA-FISH) with confocal microscopy to visualize and confirm the presence of biofilms.

Results

In 19 of 20 (95%) studied patients presenting with DFO, it was associated with an infected diabetic foot ulcer. By DNA sequencing of infected bone, Corynebacterium sp. was the most commonly identified microorganism, followed by Finegoldia sp., Staphylococcus sp., Streptococcus sp., Porphyromonas sp., and Anaerococcus sp. Six of 20 bone samples (30%) contained only one or two pathogens, while the remaining 14 (70%) had polymicrobial communities. Using a combination of SEM and PNA-FISH, we identified microbial aggregates in biofilms in 16 (80%) bone specimens and found that they were typically coccoid or rod-shaped aggregates.

Conclusions

The presence of biofilms in DFO may explain why non-surgical treatment of DFO, relying on systemic antibiotic therapy, may not resolve some chronic infections caused by biofilm-producing strains.  相似文献   
86.
Experiments were conducted to establish whether diminished solute reabsorption in the loop of Henle during acute renal failure could explain the loss of urinary concentration and participate in generating a tubuloglomerular feedback-mediated reduction in filtration rate. The electrolyte content of the fluid in the ascending limb of the loop of Henle was determined in situ by monitoring its electrical conductivity after propulsion into the distal tubule with a sudden burst perfusion. The value of the minimum electrolyte concentration decreased exponentially with increasing equilibration time, reaching a steady-state value equivalent to 27±9 mM NaCl in normal kidneys, 34±15 mM in mercuric chloride kidneys and 53±22 mM following ischaemia. A mathematical model was derived to describe the process of sodium chloride dilution from which it was possible to calculate both the permeability and transport velocity of the cortical thick ascending limb. In the normal kidney, the transport velocity was calculated to be 4.65±0.92 ·10–5 cm/s, a value not significantly different from that of the mercuric chloride or ischaemic kidneys, and the estimated permeability was 1.13±0.52·10–5 cm/s, not different from that of the mercuric chloride kidneys but significantly lower than that calculated for the ischaemic kidneys. It is concluded that for the more severely damaged ischaemic model, the loss of urinary concentrating ability was accompanied by a reduction in diluting ability of the ascending limb of the short loop of Henle, which appears to be due, at least in part, to an elevation of the passive permeability to sodium chloride in this segment.  相似文献   
87.
目的:探讨阿魏酸钠(SF)对糖尿病(DM)大鼠肾脏非酶糖基化和氧化的影响。方法:对链脲佐菌素(STZ)诱导的DM大鼠灌胃给予SF 110 mg·kg-1·d-1,治疗8周,测定各组大鼠肾重/体重、肌酐清除率(Ccr)、24 h尿蛋白定量、血清和肾皮质果糖胺(FMN)、血清和肾皮质丙二醛(MDA)含量及抗氧化酶活性,并分别测定肾皮质糖基化终产物(AGEs)含量,观察肾脏病理改变。结果:糖尿病对照组(DM组)大鼠肾重/体重、Ccr、24 h尿蛋白定量、血清FMN、肾皮质FMN和AGEs显著高于正常对照组(N组);SF治疗组(SF组)肾重/体重、Ccr、24 h尿蛋白定量、血清FMN和肾皮质AGEs显著低于DM组;DM组大鼠肾皮质和血清超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性显著低于N组,MDA含量显著高于N组,SF治疗组大鼠肾皮质和血清SOD、CAT活性显著高于DM组,MDA含量显著低于DM组:DM组大鼠肾脏病理改变异常显著,SF组的肾脏病理学改变轻于DM组大鼠。结论: SF通过保护肾脏抗氧化酶,减轻氧化应激,抑制AGEs在肾脏的沉积对DM大鼠肾脏产生保护作用。  相似文献   
88.
Pigmentary degeneration of the retina was induced by a single intraperitoneal Injection of 75mgkg of N-methyl-N-nitrosourea (MNU) In female Brown-Norway colored rats at 50 days of age, which were then observed at 24, 48 and 72 h and 7, 21,35 and 150 days after the treatment. MNU-treated rats showed selective destruction of the photoreceptor cells by an apoptotic mechanlsm 24 h after the treatment, and the destruction was completed by day 7. During the photoreceptor cell degeneration, proliferation of Miller cells and infiltratlon of macrophages was prominent 72h and 21 days aRttr the treatment, respectively. Müller cell proliferation and macrophage infiltratbn corresponded to degenerative photo-receptor cell phagocytosis, and prollferating Müller cell processes responded to stabilize the damaged retina. Pigment epithelial cell detachment from the Bruch's membrane was seen 72 h after the treatment, and migration within all layers of the retina was seen at day 7 when photoreceptor Cells were lost. At 21, 35 and 150 days after the treatment, lack of photoreceptor cells and deposition of pigment epithelial cells within the retina but not in contact to vascular endothe-lial cells were characteristic. MNU-induced photoreceptor apoptosis followed by Miiller cell and macrophage reaction then pigment epithellal cells deposition withln the retina partially resembles retinitis pigmentosa in humans.  相似文献   
89.
2型糖尿病肾病患者血清胱抑素C的检测及意义   总被引:1,自引:0,他引:1  
目的:检测糖尿病患者血清胱抑素C浓度变化,分析其在糖尿病患者早期肾损伤中的作用。方法:根据24h尿白蛋白排泄率(UAER)的测定结果,将104例糖尿病患者分为3组:单纯糖尿病组(SDM组)、早期糖尿病肾病组(EDN组)和临床糖尿病肾病组(CDN组);46名健康者作对照组;采用颗粒增强散射免疫比浊法测定血清胱抑素C水平,常规测定内生肌酐清除率、血肌酐和UAER,并对全部患者胱抑素C血清浓度与尿UAER进行直线相关分析。结果:SDM组,EDN组及CDN组间血清胱抑素C水平均有非常显著性统计学意义(P<0.01),血清胱抑素C与UAER、内生肌酐清除率及血肌酐值有良好相关性(r值分别为0.772,-0.754,0.785,P均<0.01)。结论:血清胱抑素C水平测定有助于2型糖尿病肾病的早期诊断,优于血肌酐和内生肌酐清除率,具有临床应用价值。  相似文献   
90.
目的:研究血清和糖皮质激素诱导的蛋白激酶1(serum and glucocorticoid-inducible kinase 1,SGK1)在糖尿病(DM)小鼠肾脏皮质中时间上差异性表达及意义。方法: 采用链脲佐菌素(STZ)单次腹腔注射诱导小鼠糖尿病模型。将2月龄C57BL/6小鼠随机分成10组:第1、2、3、4、6、8、12周糖尿病小鼠组(DM1、DM2、DM3、DM4、DM6、DM8、DM12)和相应的第1、4、8周正常对照组(N1、N4、N8)。分别在DM模型制作成功后第1、2、3、4、6、8、12周末收集小鼠24 h尿量,检测24 h尿蛋白量;观察肾脏病理改变;半定量RT-PCR检测小鼠肾脏皮质SGK1及结缔组织生长因子(CTGF)mRNA的表达,Western blotting检测N4、DM4、DM8组皮质SGK1、CTGF蛋白的表达。结果: 随着糖尿病病程的进展,DM组小鼠肾小球体积逐渐增大、系膜区逐渐增宽;DM组小鼠24h尿蛋白从第2周起开始逐渐增多,肾脏皮质SGK1 mRNA表达从第2周开始明显上调,在第4周达到峰值。CTGF随着糖尿病病程的进展表达逐渐递增。结论: SGK1在糖尿病早期肾脏表达峰值的出现及CTGF 持续递增的表达,提示SGK1在糖尿病肾病肾脏纤维化的发生发展过程中起重要作用。  相似文献   
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