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51.
目的 探讨重度慢性阻塞性肺疾病简称慢阻肺病人食管切除术围手术期常见并发症及其处理。方法 45例重度慢阻肺的病人在全麻联合硬膜外阻滞下进行开胸食管切除手术,围手术期处理包括术前戒烟、胸部理疗、预防和控制呼吸道感染、解痉化痰、呼吸功能锻炼、营养支持和氧疗;术后硬膜外镇痛、早期锻炼、保持呼吸道通畅,部分病人予以呼吸支持。结果 术中3例出现低氧血症。术后所有病人PaO2均有不同程度的下降,6例出现肺部感染,6例行纤维支气管镜吸痰,2例通过气管插管给予呼吸机支持,2例行气管切开术,1例酸碱平衡紊乱使用盐酸精氨酸治疗。所有病人均痊愈出院。结论 重度慢阻肺病人并非开胸食管切除手术的绝对禁忌证,积极的术前准备和严格的术后管理可减少和控制术后急性发作,有助于确保此类病人的围手术期安全和康复。  相似文献   
52.
三磷酸腺苷结合盒运转体A1与颈动脉粥样硬化斑块的关系   总被引:4,自引:0,他引:4  
目的 探讨三磷酸腺苷结合盒运转体A1(ATP binding cassette transporter A1,ABCA1)在人颈动脉粥样硬化斑块中的表达变化及作用机制.方法 收集24例人颈动脉粥样硬化斑块标本和10例肠系膜动脉标本(对照组),采用RT-PCR测定ABCA1 mRNA和视黄酸X受体α(RXRα)mRNA表达水平,并采用Western Blot检测ABCA1及RXRα的蛋白表达水平.24例人颈动脉粥样硬化斑块标本按病理分级,比较病理组织为Ⅲ级和Ⅰ级动脉粥样硬化组织间ABCA1 mRNA、RXRαmRNA表达水平及蛋白表达水平.结果 颈动脉粥样硬化斑块组的ABCA1 mRNA(0.79±0.04)和RXRα mRNA(0.73±0.04)表达与对照组相比上调,差异有统计学意义(P<0.05);ABCA1 mRNA与RXRα mRNA增加水平相关(P<0.05);颈动脉粥样硬化斑块的ABCA1蛋白表达(0.22±0.03)下调水平与对照组(0.53±0.03)相比差异有统计学意义(P<0.05);Ⅲ级和Ⅰ级动脉硬化斑块ABCA1mRNA、RXRα mRNA及蛋白表达水平差异有统计学意义(P<0.05).结论 ABCA1及RXRα蛋白表达水平下调可能是进展性动脉粥样硬化损害的关键因素.  相似文献   
53.
Objective To investigate the role of poly-lactic acid and agarose gelatin in promoting the functional recovery of the injured spinal cord. Methods Poly-lactic acid ( PLA) or agarose was embedded in the space between two stumps of the hemisectioned spinal cord. Immunohistochemistry was used to show astroglia proliferation and the infiltration of RhoA-positive cells. Locomotor activity recovery was evaluated by testing the function of hindlimbs. Results Astrogli-as and RhoA labeled non-neuronal cells accumulated in the area adjacent to the implant, while the number of RhoA-positive cells was decreased dramatically in the absence of implant. Animals implanted with agarose gelatin recovered more quickly than those with PLA, concomitant with a higher survival rate of the neurons. Conclusion Both PLA and agarose gelatin benefited the recovery of spinal cord after injury by providing a scaffold for astroglia processes. Modulation of the rigidity, pore size and inner structure of PLA and agarose gelatin might make these biodegradable materials more effective in the regeneration of the central nervous system (CNS).  相似文献   
54.
BACKGROUND: A primary tubular sodium handling abnormality has been implicated in the edema formation of nephrotic syndrome. Dopamine synthesized by renal proximal tubules behaves as an endogenous natriuretic hormone by activating D(1)-like receptors as a paracrine/autocrine substance. METHODS: We examined the time courses of the urinary excretion of sodium, protein and dopamine in puromycin aminonucleoside (PAN)-treated and control rats. The rats were sacrificed during greatest sodium retention (day 7) as well as during negative sodium balance (day 14) for the evaluation of renal aromatic l-amino acid decarboxylase (AADC) activity, the enzyme responsible for the synthesis of renal dopamine. Also, the influence of volume expansion (VE) and the effects of the D(1)-like agonist fenoldopam (10 microg/kg bw/min) on natriuresis and on proximal tubular Na(+),K(+)-ATPase activity were examined on day 7. RESULTS: The daily urinary excretion of dopamine was decreased in PAN-treated rats, from day 5 and beyond. This was accompanied by a marked decrease in the renal AADC activity, on days 7 and 14. During VE, the fenoldopam-induced decrease in proximal tubular Na(+),K(+)-ATPase activity was more pronounced in PAN-treated rats than in controls. However, the urinary sodium excretion during fenoldopam infusion was markedly increased in control rats but was not altered in PAN-treated animals. CONCLUSION: PAN nephrosis is associated with a blunted renal dopaminergic system activity which may contribute to enhance the proximal tubular Na(+),K(+)-ATPase activity. However, the lack of renal dopamine appears not to be related with the overall renal sodium retention in a state of proteinuria.  相似文献   
55.
The digestive properties of Australian elapid snake venoms have not been studied to any great extent. To address this, the in vitro digestive properties of Oxyuranus scutellatus (Australian Coastal Taipan) venom were investigated in a simulation of the in vivo conditions using the parameters reported for the stomach of snakes and representative prey for this species. The amount of soluble protein released was measured over time using a bicinchoninic acid (BCA) assay. Dismembered mouse hindlegs were injected intramuscularly with 0.1 ml O. scutellatus venom (concentration 10 mg/ml) and maintained in a micro-anaerobic, acidic environment (pH approximately 1.2-1.7) at 25 degrees C. The bathing liquid was sampled every 24 h for 7 days, and assayed for soluble protein. Statistical analysis revealed that O. scutellatus venom increased the rate at which proteins were released when compared to a negative control suggesting the potential importance of envenomation in the digestion of whole prey.  相似文献   
56.
非胰岛素依赖型糖尿病患者血清唾液酸的改变   总被引:2,自引:0,他引:2  
鲁一兵  缪珩 《江苏医药》1997,23(3):153-154
测定20例NIDDM伴有心脑血管病变的患者、20例单纯NIDDM患者的血清唾液酸(SA)水平,并与20例正常人进行比较。结果发现所有NIDDM患者的血清SA水平均显著增高(P<0.01),其中伴有心脑血管疾病患者的血清SA水平显著高于单纯NIDDM患者(P<0.05),同时血清SA水平与血清胰岛素及C肽水平、收好压之间存在相关。提示血清SA水平与NIDDM患者的心脑血管疾病关系密切,可能是心脑血管并发症发生的一个危险因素。  相似文献   
57.
孕妇血清与初乳中分泌型IgA含量的关系   总被引:1,自引:0,他引:1  
目的探讨孕妇营养与初乳中分泌型免疫球蛋白A(SIgA)含量的关系。方法对101例孕妇作了膳食营养评价,并对其血液营养学指标与产后第3d初乳SIgA含量进行相关分析。结果孕妇血清IgA与初乳SIgA呈明显的正相关(r=0.498P<0.01);血清甘油三酯与初乳SIgA呈明显的负相关(r=-0.338P<0.005);血清叶酸与初乳SIgA呈明显正相关(孕中期r=0.737P<0.001,孕晚期r=0.362P<0.01)相关呈高度显著性。结论初乳SIgA与孕妇个体免疫状态以及孕期代谢状态有关。  相似文献   
58.
两种鼠蚤成熟过程中组织化学研究Ⅰ糖原和PAS物质   总被引:3,自引:0,他引:3  
目的:探讨不等单蚤Monopsyllns anisus(Rothchild)和级慢细蚤Leptopsylla segnis(Schoenherr)吸血消化成熟过程中糖原和PAS物质的变化。方法:用高碘酸-希夫反应(Periodic acid-Schiff reaction PAS)法显示未吸血蚤、吸血后不同消化时间蚤体内糖原和PAS物质。结果:2种蚤糖原和PAS物质以脂肪体含量最高。吸血后成蚤消化道各部分PAS反应均有增高,不同消化时间(24、48、72h)不存在显著差异。2种蚤中雌蚤吸血后卵黄细胞发育过程中PAS反应的变化相似,但不等单蚤发育较缓慢细蚤迟缓。结论:吸血将导致2种蚤消化道糖原不同程度的增加。亦能促进雌蚤卵黄细胞的发育。  相似文献   
59.
Effect of distension on adrenergic innervation of the rat urinary bladder   总被引:1,自引:0,他引:1  
Summary The effect of distension on adrenergic innervation was investigated in the rat urinary bladder. Bladders were distended for 3 h by forced diuresis and ballon obstruction, and specimens were taken from the bladder dome, body and neck for the demonstration of glyoxylic acid-induced fluorescence of catecholamines. Depletion of catecholamines started after 10 h and was almost complete after 2 days. The fluorescence had recovered part way after 5–7 days and was practically normal after 21 days. Small, intensely fluorescent (SIF) cells in the ganglia continued to leak catecholamines throughout the 21-day study period. The primary clinical success of distension therapy for the treatment of unstable bladder may be at least partly due to a reversible disturbance in the function of the adrenergic nerves, which have an excitatory alpha-adrenergic dominance in such cases, but the persistent leakage from SIF cells raises the question of whether distension causes prolonged disturbances in bladder function.  相似文献   
60.
Summary: Current peritoneal dialysis solutions are not biocompatible, particularly in respect to low pH, high osmolality and use of lactate. In addition, glucose is not an ideal osmotic agent. Recent advances in the formulation of peritoneal dialysis fluids aim to provide a more physiological environment to preserve membrane integrity. the effects of pH and lactate have been overcome by the use of bicarbonate based solutions whilst icodextrin (glucose polymers) often prolonged ultrafiltration in spite of being isomotic to uraemic plasma. Future formulations will see a combination of osmotic agents (including amino acids) and bicarbonate to achieve a more biocompatible solution whilst still meeting the ultrafiltration needs of the patients. Additives (glycosaminoglycans, procysteine) may protect the peritoneum from free radical injury.  相似文献   
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