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31.
Intestinal cytokine response after gut ischemia: role of gut barrier failure   总被引:15,自引:0,他引:15  
OBJECTIVE: To investigate the effect of intestinal ischemia with and without a reperfusion injury on intestinal cytokine production and gut permeability. SUMMARY BACKGROUND DATA: In humans and in animal models, the gut has been implicated as a cytokine-producing organ after ischemia/reperfusion (I/R)-type injuries. Because of the limitations of in vivo models, it has been difficult to demonstrate directly that the gut releases cytokines after an I/R injury or whether there is a relation between the magnitude of the ischemic process and the cytokine response. METHODS: Ileal mucosal membranes from rats subjected to sham or 45 or 75 min of superior mesenteric occlusion (SMAO) or 45 minutes of SMAO and 30 minutes of reperfusion (SMAO 45/30) were mounted in the Ussing chamber system. Levels of tumor necrosis factor-alpha and interleukin-6 were serially measured in the mucosal and serosal reservoirs of the Ussing system, as was mucosal permeability as reflected by the passage of bacteria or phenol red across the ileal membrane. In a second group of experiments, Escherichia coli C25 was added to the mucosal reservoir to determine if the cytokine response would be increased. RESULTS: Mucosal and serosal levels of tumor necrosis factor-alpha were equally increased after SMAO, with the highest levels in the 75-minute SMAO group. The highest levels of interleukin-6 were found in rats subjected to 75 minutes of SMAO or SMAO 45/30; the serosal levels of interleukin-6 were four to sixfold higher than the mucosal levels. The addition of E. coli C25 resulted in a significant increase in the amount of interleukin-6 or tumor necrosis factor-alpha recovered from the mucosal reservoir. Increased ileal membrane permeability was observed only in rats subjected to 75 minutes of SMAO or SMAO 45/30. CONCLUSION: These results directly document that the levels of tumor necrosis factor-alpha and interleukin-6 released from the gut increase after an ischemic or I/R injury, such as SMAO, and that there is a relation between the magnitude of the gut ischemic or I/R insult and the cytokine response.  相似文献   
32.
Leupeptin protects sensory hair cells from acoustic trauma   总被引:4,自引:0,他引:4  
  相似文献   
33.
在我国中等发达及上农村地区,大病统筹合作医疗或医疗保险以其可缓解农村居民的就医经济风险而受到欢迎,但是在方案的拟订过程中尚存在一些明显的技术缺陷,比如,“大病”的技术定义、农村居民就医经济风险分析、风险临界线界定、保险经付比测算和保险费率厘定等,这些技术的缺乏,已严重影响农村合作医疗或医疗保险的推广和实施效果。  相似文献   
34.
Aggregation inhibitory activity of minor acetophenones from Paeonia species   总被引:4,自引:0,他引:4  
Lin HC  Ding HY  Ko FN  Teng CM  Wu YC 《Planta medica》1999,65(7):595-599
Two minor acetophenones, 2,5-dihydroxy-4-methoxy-acetophenone (2) and 2,5-dihydroxy-4-methylacetophenone (7) from Paeonia species were found to selectively inhibit the aggregation of rabbit platelets induced by arachidonic acid. They were more potent than the major compound, paeonol (1), and 7 also inhibited the formation of TXA2 and PGD2 from arachidonic acid.  相似文献   
35.
中药川芎中无机阴离子和有机酸成分的研究   总被引:10,自引:0,他引:10  
目的:研究中药川芎中有机酸和无机阴离子的同时分析方法。方法:采用非抑制型阴离子交换色谱法,色谱柱为ShimpackICA1,流动相为08mmol·L-1邻苯二甲酸氢钾。结果:川芎提取液中3种有机酸和3种无机阴离子得到了较好的分离。结论:该方法分析速度快,准确,灵敏度高。  相似文献   
36.
口服Ⅱ号避孕药对血小板功能及血液凝固的影响   总被引:2,自引:1,他引:1  
为了解口服Ⅱ号避孕药对血小板功能及血液凝固性的影响,本文对65名连续服药妇女进行了研究。她们的年龄为27~45(平均36.5)岁。服药期限1~17(平均6.7)年。测定项目有纤维蛋白原,血小板粘附率,血小板聚集率,Ⅷ因子相关抗原,抗凝血酶活力等。20例未服药妇女作对照。测定结果服药组血小板粘附率、聚集率及纤维蛋白原比对照组明显增高(P<0.001)。Ⅷ因子相关抗原略增高,但无统计学意义。抗凝血酶活力显著降低(P<0.001)。本文就急性心肌梗塞及血栓栓塞的潜在可能性等问题进行了讨论,并对预防此类并发症提出了建议。  相似文献   
37.
The synthesis of hybrid "cationic metalloporphyrin-intercalator" molecules is reported. These molecules are based on 9-methoxyellipticine as intercalator and tris-(4-N-methylpyridiniumyl)metalloporphyrins having a 4-aminophenyl or a 4-hydroxyphenyl group for the attachment of the linker. The effect of the length of linker (7-13 bonds), the chemical nature of the linking group (with a carboxamido or an ether function), the position of amino group between the two parts of hybrid molecules, the number of intercalator moieties (ellipticinium) covalently attached to the metalloporphyrin, and the nature of the central metal atom (Mn, Fe, Zn) on the biological activity of these hybrid molecules were studied. In addition, these molecules have a high affinity for double-stranded DNA (affinity constant of hybrid molecule 9Mn,Me = 2.3 x 10(9) M-1 for poly[d(A-T)] and 2.8 x 10(8) M-1 for poly[d(G-C)] and are cytotoxic against murine leukemia cells L1210 in vitro (IC50 of 9Mn,Me = 0.8 microM). Their cytotoxicities are dependent on the nature of central atom. Iron derivatives are less active than manganese analogues and the corresponding zinc derivatives are nearly inactive despite their same affinity for nucleic acids. These highly water-soluble hybrid molecules could be considered as efficient bleomycin models based on a cationic metalloporphyrin.  相似文献   
38.
My late father Dr. DING Hong-shan was a senior Chinese medical doctor and learnt thumb-massage therapy from his forefathers. In his decades of years of clinical practice, upon the physiological nature of the children‘s tender constitution, he created a “one-hand and three-acupoint Tuina” (the thumb, forefinger and middle finger of one hand simultaneously massaging three acupoints or three meridians) in combination with thumb-massage therapy. It is suitable for childhood limb diseases, especially for infantile cerebral palsy. It is now introduced as follows.  相似文献   
39.
40.
儿童期单纯肥胖症的行为治疗   总被引:12,自引:2,他引:12  
为研究适合中国肥胖儿童的行为治疗方案及效果,对24例(男女各12例)13岁单纯肥胖儿童进行3年行为治疗纵向研究。24名同年龄、性别、年级非肥胖儿童为正常对照组。观测参数有身高、体重、四处皮脂、腰、臀围及其比例、有氧运动能力(最大耐受时间和运动距离)。体育测试成绩包括引体向上、跳远、800米跑、仰卧起坐,满分为30分。按运动处方每天运动2小时,每周5天。在医生指导下肥胖儿童写行为分析和行为矫正方案。有关肥胖指标年减少率(男/女)体脂含量为23%~42%,肥胖度2.8%~2.1%,腰/臀比2.5%~2.6%,四处皮脂和5.7%女0.8%~1.0%),有氧能力明显进步。体育成绩肥胖干预组30%达满分,70%为27~29分。肥胖对照组60%为20分,30%为15~19分。提示儿童期单纯肥胖症的干预方案应以健康教育和运动处方为基础,行为治疗为核心技术;在家庭日常生活中持续进行,家长、教师、医务人员应共同参与。  相似文献   
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