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123.
I Durieu F Abbas-Chorfa J Drai J Iwaz J-P Steghens M Puget R Ecochard G Bellon 《The European respiratory journal》2007,29(5):958-964
The present authors investigated whether cystic fibrosis is linked to a defect in fatty acids and assessed the impact of the main patients' characteristics on the levels of several fatty acids, mostly during respiratory exacerbation and after antibiotic therapy. Fatty acid phospholipid and cholesteryl ester levels were measured in stable-state patients and controls. No differences were found concerning either the fractions of palmitic and oleic acids or the cholesteryl esters of alpha-linolenic and arachidonic acids. However, phospholipids of alpha-linolenic and arachidonic acids, as well as cholesteryl esters and phospholipids of stearic and linoleic acids, were lower in patients than in controls, but fractions of dihomo-gamma-linolenic, docosatetraenoic, docosapentaenoic, palmitoleic and eicosatrienoic acids were higher. Fatty acid levels, oxidative stress markers, nutrients, body mass index and forced expiratory volume in one second (FEV(1)) were measured in patients before and after antibiotic courses for bronchial exacerbation. After adjustments, palmitic, stearic, alpha-linolenic, linoleic, arachidonic, palmitoleic and oleic acids generally decreased during exacerbation but almost all increased after antibiotic courses. Nearly all fractions increased along with FEV(1) and a positive relationship linked fatty acids to lipid hydroperoxides. There was no general drop in fatty acids. Patients' fatty acid profiles depended on the pulmonary function and the inflammation state. 相似文献
124.
化痰方、肝脾方抗大鼠脂肪肝模型作用机制的比较研究 总被引:7,自引:1,他引:6
目的 :探讨和比较化痰方、肝脾方抗大鼠脂肪肝模型作用机制。方法 :用高脂饮食联合四环素腹腔注射致大鼠脂肪肝模型 ,观察肝组织病理变化 ,检测肝功能 (ALT、AST)、血甘油三酯 (TG)、肝匀浆TG、游离脂肪酸 (FFA)、丙二醛 (MDA)的含量。并与正常组、东宝肝泰组对照。结果 :三个用药组的血清ALT、AST及肝匀浆FFA、TG、MDA均显著低于模型组 (P <0 .0 1 ) ,并显示抗脂肪肝的作用强弱依次为 :肝脾组优于化痰组优于东宝组 (P <0 .0 5或P <0 .0 1 )。结论 :促进脂质代谢、抗脂质过氧化可能是化痰祛浊、疏肝健脾法治疗脂肪肝作用的主要机制 相似文献
125.
The elderly represent an increasingly important and challenging subset of the population of patients with ischemic heart disease. They are more likely to have comorbid conditions, atypical presentations, and unfavorable outcomes than their younger counterparts. Some of these findings are undoubtedly related to the structural and functional changes in the cardiovascular system associated with aging. The available data suggest that standard pharmacologic, thrombolytic, and definitive revascularization techniques have important roles in the therapy of geriatric patients but have been underused. 相似文献
126.
选择性髂内动脉结扎与栓塞对盆腔血供的影响 总被引:5,自引:0,他引:5
目的:旨在探讨选择性髂内动脉结扎与栓塞两种方法对盆腔血供的影响。方法:将两组犬在膀胱上动脉分支以下之髂内动脉分别行结扎与栓塞,对比观察两组膀胱创面出血、盆腔动脉造影及盆腔脏器组织学变化,以确定其盆腔脏器的血供情况。结果:①结扎组膀胱创面出血明显大于栓塞组;②结扎组髂内动脉侧支循环建立时间明显早于且数目多于栓塞组;③两组盆腔脏器均未见缺血坏死。结论:栓塞组阻断髂内动脉侧支循环的数目多于结扎组,故对盆腔血供的影响大于结扎组。避免髂内动脉阻断范围过广可减少盆腔脏器缺血坏死的机会。 相似文献
127.
J M Frederick 《Experimental eye research》1987,45(6):933-945
The emergence of GABA-accumulating neurons was studied from stages 29 to 40 during retinal histogenesis in the chick, covering embryonic (E) days E6-E14, using autoradiographic analysis following incubation of isolated retinas with [3H]GABA (2 microM). Analysis was restricted to central retina which is more advanced in its differentiation than the periphery. On E6 numerous mitotic figures were present along the scleral border of the unstratified neuroepithelium. Specific localization of [3H]GABA was associated initially with somata situated in middle regions of the retinal expanse. Occasionally contiguous pairs of labeled cells were seen. The inner plexiform layer makes its appearance during E7; at that time silver grains were present over cell bodies located in the ganglion cell layer and the proximal portion of the inner nuclear layer, those of probable amacrine cells. As retinal stratification continued, more cells were observed to have elaborated membrane systems for GABA uptake with varying degrees of affinity. By E8, although dividing, non-labeled cells were in close proximity, GABA-labeled cells were observed in positions of horizontal cells. By E14, the pattern of label distribution appeared essentially similar to that reported for adult retina, i.e. [3H]GABA labeling was observed over horizontal cells and their processes, subpopulations of amacrine cells which appear to ramify extensively across the inner plexiform layer, selected perikarya of the ganglion cell layer, and the nerve fiber layer. In addition, a subpopulation of labeled photoreceptors, some identified as cones by virtue of oil droplets, was observed. Thus, preferential accumulation of GABA appears during E6, prior to formation of either inner or outer plexiform layers. The localization of [3H]GABA demonstrates that ganglion and amacrine cell bodies are labeled initially, followed by horizontal cells. Specific accumulation of [3H]muscimol, a potent agonist of GABA receptors, appears about E12 over cells located in proximal regions of the inner nuclear layer; these somata later ramify in sublaminae 2 and 4 of the inner plexiform layer. 相似文献
128.
R. I. Markowitz W. Frederick N. S. Rosenfield J. H. Seashore P. H. Duray 《Pediatric radiology》1987,17(4):269-272
We describe a case of a full-term infant with severe respiratory failure and pulmonary insufficiency caused by an anomaly
consisting of a single, unilobar lung arising from the trachea and situated in the middle mediastinum. Plain film, echocardiogram,
and surgical aspects will be described and correlated with the post mortem findings and embryologic considerations. We were
unable to find a similar case reported in the literature and conclude that this rare lesion represent an intermediate form
between total and unilateral pulmonary agenesis.
Presented at the Society for Pediatric Radiology, Washington D.C. 12 April 1986 相似文献
129.
采用CHO细胞HGPRT位点突变测定系统观察了核黄素、尼克酰胺和锌等微量营养素对甲基苄基亚硝胺(MBNA)致细胞突变作用的影响。结果表明,在RPMI1640培养基中添加核黄素(2.6~13.0μmol/L)或尼克酰胺(40~120μmol/L)可显著抑制MBNA的致细胞突变作用。联合应用核黄素、尼克酰胺和锌效果更佳。提示:核黄素等微量营养素可能具有阻止细胞癌变的作用,为应用微量营养素干预治疗癌变过程提供了一定的理论依据。 相似文献
130.
牙科用基托材料的溶出物分析 总被引:2,自引:0,他引:2
本文为预测聚甲基丙烯酸甲酯(PMMA)在口腔修复常规制备后.在体液中溶出情况,应用高速液相色谱仪,对义齿基托用PMMA材料.在甲醇中浸渍后主要溶出物甲基丙烯酸甲南(MMA)和过氧化苯甲酰(BPO)进行了分析探讨。实验证明采用高建液相色谱,以甲醇为模拟体液可快速、定量、正确地测出PMMA中残留MMA和BPO的溶出情况.从而预测PMMA义齿修复体初戴前浸入水后.在口腔中溶出MMA和BPO的作用较戴前处于干燥状态者更为适宜。 相似文献