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1.
循环休克肾上腺素能受体失敏研究进展   总被引:9,自引:0,他引:9  
循环休克肾上腺素能受体失敏研究进展第三军医大学大坪医院野战外科研究所(重庆400042)刘良明胡德耀陈惠孙AdvancesofthedesensitizationofadrenergicreceptorsduringcirculatoryshockL...  相似文献   

2.
TRH与多巴胺伍用抗高原创伤失血性休克大鼠的作用第三军医大学大坪医院野战外科研究所(重庆400042)成都军区西藏总医院(拉萨850003)刘良明卢儒权林秀来但飞君张勇义黄永红胡德耀陈惠孙目的:在西藏拉萨进行现场实验,观察TRH与多巴胺伍用对高...  相似文献   

3.
N-乙酰半胱氨酸对肠道缺血再灌注及远处器官损伤的保护作用第三军医大学大坪医院野战外科研究所(重庆400042)肖南刘萍刁有芳田昆仓刘韧自由基在创伤性休克时组织器官损伤中的作用已为人们所公认,自由基损伤是体内自由基产生和清除失衡的结果。体内巯基氧化还原...  相似文献   

4.
δ、κ阿片受体拮抗剂在治疗创伤失血性休克中的作用第三军医大学大坪医院野战外科研究所(重庆400042)胡德耀潘学坤刘良明卢儒权家兔9只,乙醚麻醉,右股骨中断开放粉碎性骨折及动脉放血至667kPa(50mmHg)并维持45min完成休克模型(为休克0...  相似文献   

5.
失血性休克后发生脓毒性休克的机制第三军医大学大坪医院野战外科研究所(重庆400042)陈惠孙刘宝华蒋建薪杜文华赵云平失血性休克后发生肠道内细菌内毒素移位是多器官衰竭的主要原因。我们研究发现大鼠失血性休克血液回输后4h内肠道上皮细胞apoptosis明...  相似文献   

6.
MCI-154抗休克作用及其改善心功能的机理   总被引:2,自引:0,他引:2  
MCI-154抗休克作用及其改善心功能的机理第三军医大学大坪医院野战外科研究所(重庆400042)胡德耀梅建民殷作明刘良明卢儒权陈惠孙一、MCI-154抗休克作用:家兔内毒素休克低排期模型在充分容量复苏的前提下,静脉给予MCI-15402mg/kg...  相似文献   

7.
海水浸泡失血性休克条件下磷脂酶A2的变化第三军医大学大坪医院野战外科研究所(重庆400042)李萍刘建仓陆松敏贾后军万志红磷脂酶A2(PLA2)是特异性的水解酶,它在机体各组织细胞中广泛分布,血清中PLA2活性的升高与循环衰竭、血压下降和休克的严重程...  相似文献   

8.
创伤病人血清免疫抑制性研究   总被引:9,自引:0,他引:9  
创伤病人血清免疫抑制性研究李磊,王正国,张玉纯,胡承香(第三军医大学野战外科研究所大坪医院,重庆630G42)为证实创伤病人血清中是否同样存在免疫抑制性异常蛋白,本文对部分创伤病人血清进行了研究。1材料与方法1.1病例选择及采样取既往健康,无传染病和...  相似文献   

9.
癫术前定位评估@许尚臣!600014,山东济南$山东省千佛山医院 @李劲梅$重庆医科大学第一医院癫外科;;术前评估;;皮质定位~~  相似文献   

10.
μ,δ,κ阿片受体在创伤失血性休克大鼠心血管功能抑制中的作用第三军医大学大坪医院野战外科研究所(重庆400042)刘良明卢儒权胡德耀陈惠孙陈艳但飞君目的:探讨μ,δ和κ阿片受体与创伤失血性休克大鼠心血管功能抑制的关系,明确这三种亚型阿片受体是哪型或哪...  相似文献   

11.
Prostaglandins (PGs) are arachidonic acid metabolites produced by the action of the enzyme cyclooxygenase (COX). Although PGs are important mediators of inflammation in various diseases, they also are key factors in the physiological regulation of gastrointestinal and renal homeostasis. The finding that two distinct COX isoforms are responsible for PG synthesis has provided basis to the opposite actions of PGs in inflammation and homeostasis regulation. COX-1-derived PGs are thought to mediate cytoprotective actions on the gastrointestinal mucosa, whereas COX-2-derived PGs are assumed to display pro-inflammatory properties. This dichotomy has led to the development of selective inhibitors of COX-2 activity which are safer for the gastrointestinal mucosa than the classic inhibitors of both COX isoforms. However, some COX-2 anti-inflammatory properties have been recently demonstrated in several experimental models of inflammation. These studies have raised some concern about the potential adverse effects of COX-2 selective inhibitors. In addition, there is evidence that COX-1 displays pro-inflammatory properties, depending on the organ and on the stage of the inflammatory response. This review will focus on the roles of COX-1 and COX-2 in inflammation, based on studies involving pharmacologic COX inhibitors as well as COX knock-out mice, with a particular emphasis on the gastrointestinal tract.  相似文献   

12.
In addition to housekeeping cyclooxygenase (COX)-1, which is constitutively expressed in many body cells, an inducible COX-2 has been described and cloned. Induction or presence of COX-2 has been reported not only in isolated cells, but also in cells in various tissues, as well as in both physiological and pathophysiological states, including acute exudative inflammation, proliferative inflammation, animal arthritis, rheumatoid arthritis, angiogenesis, bone absorption, gastric ulcer, colon cancer, hyperalgesia, Alzheimer's disease and certain states of the kidney, brain and female reproductive organs. This review article introduces results from recent works in these fields. COX-1- or COX-2-knockout mice may provide many clues on the roles of COX-2, but may simultaneously cause unnecessary confusion in the recognition of the roles of COX-2, and this is discussed. Recently the roles of COX-2 in exudative inflammation and the anti-inflammatory effects of selective COX-2 inhibitors have been questioned. This is discussed in the text. Prostanoids mediate signals to adjacent cells to provide fine regulation of cellular function. Because of the short duration of the expression of COX-2 gene and protein, COX-2 must play some roles different from those of COX-1 gene and protein in vivo. It is not yet possible to identify all the roles of COX-2, but in some tissues, such as the kidney, the brain and others, COX-2 may be expressed constitutively, whereas the prostaglandin generation by COX-2 may replace that by COX-1 in some states (or vice-versa). Precise analyses of the expression of COX-2 may disclose fine modulation of cellular and organ functions by PGs. Several selective or preferential COX-2 inhibitors have been developed and were shown to be effective in clinical trials. Most were reported to be free of adverse gastrointestinal effects, but it should be noted that in the healing process of gastric ulcers and in sodium-restricted states, adverse effects of selective COX-2 inhibitors could be expected. Soon, with more detailed knowledge of the delicate roles of COX-2 in vivo, effective and safe application of COX-2 inhibitors should be realized.  相似文献   

13.
Chronic venous ulcers are an example of abnormal wound healing showing chronic inflammation which together with the underlying vascular pathology results in delayed healing. Prostaglandins are among the most important mediators of inflammation. They have proinflammatory effects, predominantly by affecting the vasculature. Cyclooxygenase (COX) is the rate-limiting enzyme in prostanoid synthesis. It is present in two isoforms: COX-1 (constitutive cyclooxygenase) which is produced in the body to maintain normal haemostatic functions, and COX-2 (inducible cyclooxygenase), which is induced during inflammation in response to cytokines. Using immunoenzymatic labelling and western blot analysis, this study has shown that both COX-1 and COX-2 were up-regulated in chronic venous leg ulcers by comparison with normal human skin. De novo appearance of COX-2 in chronic venous ulcers was demonstrated, which is not seen in normal human skin. The main cellular sources of both COX isoforms are macrophages and endothelial cells. COX-2 is also produced by mast cells and fibroblasts. A COX radioimmunoassay showed up-regulation of COX activity in chronic venous ulcers compared with normal skin (p<0.05). Up-regulation of COX-1 in chronic venous leg ulcers could produce prostacyclin, which contributes to angiogenesis. Thus, inhibition of COX-1 by non-steroidal anti-inflammatory drugs (NSAIDs) could increase the local ischaemia and hypoxia associated with chronic venous ulcers. On the other hand, up-regulation of COX-2 is most likely responsible for the persistent inflammation in chronic venous leg ulcers. COX-2 selective inhibitors could therefore be effective in the treatment of chronic venous ulcers.  相似文献   

14.
Angiogenesis plays a key role in the development of malignant tumors. To clarify the roles of cyclooxygenase (COX) in malignant tumor development and angiogenesis, we investigated the effects of COX inhibitors on two kinds of gastrointestinal cancer xenograft, one of which overexpresses COX-2 and the other expresses no COX, in nude mice in vivo. There was a positive correlation between tumor volume and angiogenesis within the xenograft. Oral administration with a specific COX-2 or a nonspecific COX inhibitors lowered the expression of potent angiogenic factors; vascular endothelial growth factor and basic fibroblast growth factor, reduced angiogenesis and growth, induced apoptosis, and suppressed cell replication of the COX-2 overexpressing cancer xenografts in a dose-dependent manner. A nonspecific COX inhibitor, not a specific COX-2 inhibitor, reduced growth and angiogenesis of non-COX expressing cancer xenograft by inhibition of COX-1 in vascular endothelial cells. These results demonstrate that COX inhibitors suppress angiogenesis and tumor growth by inhibiting expression of angiogenic factors and vascular endothelial cell growth. They support the hypothesis that COX plays an important role in cancer growth via angiogenesis. These findings offer a new strategy against cancer using COX inhibitors (nonsteroidal anti-inflammatory drugs).  相似文献   

15.
Cyclooxygenase-2: molecular biology, pharmacology, and neurobiology   总被引:16,自引:0,他引:16  
In the nervous system, prostanoids are well recognized as mediators in a variety of processes, including fever generation, modulation of the stress response, sleep/wake cycle, control of cerebral blood flow, and hyperalgesia. Two isoforms of cyclooxygenase (COX), the enzyme that catalyzes the conversion of arachidonic acid to prostanoids, are now recognized: a constitutively expressed COX-1 and a highly regulated COX-2. New molecular and pharmacologic tools have provided a better understanding of the roles of COX-generated prostanoids in the nervous system. Other studies reveal that COX may represent an important target for new therapeutic approaches to neurologic disorders. This review summarizes our current understanding of cyclooxygenase expression and prostanoid actions in the nervous system, with special reference to COX-2 and studies demonstrating its expression in different cell types responding to a variety of stimuli. A brief review of the molecular biology, pharmacology, and primary actions of COX-2 outside of the nervous system provides a context for understanding potential neurobiological roles for COX-2 and prostanoid production. Information about the role of COX in human neurological disorders, including cerebrovascular disease, Alzheimer' s disease, and hyperalgesia, is covered in the last section.  相似文献   

16.
The eicosanoids, prostaglandin E2 (PGE2) and thromboxane A2 (TXA2), are involved in inflammatory events. TXA2 has potentially pro-inflammatory actions and PGE2 has actions which can be considered both pro- and antiinflammatory. Therefore, it is potentially significant that production of TXA2 and PGE2 by stimulated monocytes have very different time courses. TXA2 synthesis is immediate and dependent on cyclooxygenase Type 1 (COX-1) activity whereas PGE2 synthesis is delayed and dependent on COX-2 activity. These apparent COX-isotype dependencies of TXA2 and PGE2 synthesis can be explained by differences in the affinities of TXA synthase and PGE synthase for the common substrate, PGH2. The findings have implications for the use of NSAIDs and selective COX-2 inhibitors whose actions can increase the monocyte TXA2/PGE2 ratio.  相似文献   

17.
Cyclooxygenase-1 (COX-1) and cyclooxygenase -2 (COX-2) are known to play a role in the carcinogenesis of many human and animal primary epithelial tumours. However, expression of COX-1 and -2 has not been investigated in canine nasal epithelial carcinoma, a rare form of neoplasia. COX-1 immunolabelling was demonstrated in normal canine nasal mucosa and in a minority of neoplastic specimens. Cytoplasmic COX-2, however, was strongly expressed in the majority of canine nasal carcinomas. In addition, COX-2 expression was demonstrated in dysplastic epithelium and in a proportion of stromal cells. Co-expression of both enzyme isoforms was revealed by confocal laser scanning microscopy. The results indicate that COX-2 is overexpressed in a proportion of naturally occurring canine nasal carcinomas, suggesting its possible role in canine nasal tumorigenesis.  相似文献   

18.
The non-steroidal anti-inflammatory drugs (NSAIDs) do not reverse the disease process, but they provide much needed relief from pain and inflammation by inhibiting cyclooxygenase (COX) enzyme mediating the inflammatory pathway. NSAIDs cause number of death as a result of upper gastrointestinal damage. These agents also have unwanted effects on lower bowel, lungs, kidney and cardiovascular symptom. Coxibs are selective inhibitor of cyclooxygenase (COX)-2 and spares the COX-1 induced side effects i.e. gastric ulceration. Therefore in present study we compared the adverse effects of diclofenac sodium (diclo) a non-selective NSAID and valdecoxib (valde), a selective NSAID attherapeutic and subtherapeutic doses. Histological and biochemical changes of liver were observed. Beside that gross examination of the stomach mucosa for ulceration along lesser curvature too observed. For liver functions we estimated serum aspartate aminotransferase (AST), alknine aminotransferase (ALT), lactate dehydrogenase (LDH) and alkaline phosphatase (ALP). Experiment was carried out by administration of drugs for period of 30 days. Liver sections of diclo &; valde groups showed histological changes, which were more prominent with therapeutic dose of valde. The biochemical changes, subtherapeutic dose of diclo showed increase in ALP only. On the other hand subtherapeutic dose of valde showed significant changes in AST, high significant changes in LDH &; ALP Whereas therapeutic doses of diclo and valde showed highly significant increase in hepatic biochemical parameters i.e. AST, ALT, ALP, LDH.Thus it may conclude that higher doses of COX-1&;2 inhibitors can lead to acute hepatitis and other hepatic complications.  相似文献   

19.
目的探讨环氧化物酶-2(cyclooxygenase type2,COX-2)及I型前列腺素合成酶(membrane associated prostaglandin E-1,mPGES-1)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例肠系膜动脉标本做对照组,应用免疫组织化学及逆转录PCR方法测定COX-2及mPGES-1mRNA表达水平,Western印记方法检测COX-2及mPGES-1的蛋白表达水平。比较不同程度动脉粥样硬化组织间COX-2、mPGES-1 mRNA表达水平及蛋白表达水平。结果颈动脉粥样硬化斑块组的免疫组织化学染色检测COX-2和mPGES-1呈阳性表达,斑块组COX-2 mRNA和mPGES-1 mRNA表达与对照组相比上调,差异有统计学意义(P〈0.05);COX-2及mPGES-1 mRNA上调水平相关(P〈0.05):颈动脉粥样硬化斑块的COX-2蛋白表达上调水平与对照组相比差异有统计学意义(P〈0.05);颈动脉粥样硬化斑块COX-2、mPGES-1 mRNA及蛋白表达水平与病理损害程度有关,差异有统计学意义(P〈0.05)。结论COX-2及mPGES-1基因表达水平上调可能是进展性动脉粥样硬化损害的关键因素。  相似文献   

20.
目的探讨环氧化物酶-2(cyclooxygenase type 2,COX-2)及Ⅰ型前列腺素合成酶(membrane associated prostaglandin E-1,mPGES-1)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例肠系膜动脉标本做对照组,应用免疫组织化学及逆转录PCR方法测定COX-2及mPGES-1mRNA表达水平,Western印记方法检测COX-2及mPGES-1的蛋白表达水平。比较不同程度动脉粥样硬化组织间COX-2、mPGES-1 mRNA表达水平及蛋白表达水平。结果颈动脉粥样硬化斑块组的免疫组织化学染色检测COX-2和mPGES-1呈阳性表达,斑块组COX-2 mRNA和mPGES-1 mRNA表达与对照组相比上调,差异有统计学意义(P<0.05);COX-2及mPGES-1 mRNA上调水平相关(P<0.05);颈动脉粥样硬化斑块的COX-2蛋白表达上调水平与对照组相比差异有统计学意义(P<0.05);颈动脉粥样硬化斑块COX-2、mPGES-1 mRNA及蛋白表达水平与病理损害程度有关,差异有统计学意义(P<0.05)。结论COX-2及mPGES-1基因表达水平上调可能是进展性动脉粥样硬化损害的关键因素。  相似文献   

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