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71.
The purpose of this study was to investigate the intestinal hemodynamics and gut glutamine metabolism during endotoxemia, and their correlation with altered intestinal absorptive capacity and permeability. Seventeen Sprague-Dawley rats were used in the study. The endotoxin group (ENDO) recieved endotoxin (10 mg/kg intraperitoneally,n=9), while the control group (CONT,n=8) received saline injection. Twelve hours later, D-xylose (0.5 g/kg) and fluorescein isothiocyanate-dextran (FITC-dextran, 750 mg/kg) were given by oral gavage. One hour later abdominal aortic (AA) blood flow, superior mesenteric venous (SMV) flow, mean arterial pressure (MAP), central venous pressure (CVP), and SMV pressure (SMVP) were also measured. The MAP, AA, and SMV blood flow decreased (P<0.05), while the CVP and SMVP increased (P<0.05) in the ENDO group as compared with the CONT group. The ENDO group showed significant decreases for both intestinal glutaminase activity and net intestinal glutamine uptake (P<0.05). The D-xylose concentration in SMV decreased significantly (P<0.05) in the ENDO group as compared with the CONT group. However, the plasma FITC-dextran concentration showed no significant difference between the groups. Endotoxin produced a hypodynamic effect in rats 12h after intraperitoneal administration in association with both a decreased intestinal glutamine metabolism and an absorptive capacity.  相似文献   
72.
观察126例人类转移癌,分析比较淋巴样细胞浸润(LI)程度与患者年龄、病理类型、组织分化和核异型程度的关系。结果表明:患者年龄及病理类型与LI程度无关;组织分化程度在LI上虽有差别,但无对应性关系;而核异型程度与LI关系密切。核异型性愈明显,LI程度愈高,反之亦然。这说明核分级不仅可以反映宿主免疫反应的高低,也可提示转移癌抗原性的强弱。  相似文献   
73.
本文报告23例次ATP治疗PSVT的效果,总有效率56.5%,9例次高浓度快速注射者8例转复。器质性心脏病者副作用较多,1例冠心速注高浓度ATP后,发生心室颤动和阿-斯氏综合征。这一结果提示:药物浓度和注射速度是影响疗效的主要因素,PSVT伴AVB者疗效也很低;病因和药物浓度是决定副作用的因素。因此,对于器质性心脏病者,尤其冠心病人,应避免高浓度快速静脉注射ATP。  相似文献   
74.
The edema-producing activity of NNAVPLA2, an acidic phospholipase A2 (PLA2) enzyme from Naja naja atra venom (NNAV), was less potent than that of TMVPLA2 II, a basic PLA; from Trimeresurus mucrosquamatus venom (TMV). These edema-forming effects were greatly suppressed by pretreatment of rats with diphenhydramine/ methysergide or compound 48/80, which reduced the tissue content of histamine and serotonin. Heparin abolished and suppressed the paw edema caused by protamine and TMVPLA2 II, respectively, but had no effect on the NNAVPLA2-induced response. In isolated rat peritoneal mast cells, both PLA2 concentration dependently induced the release of histamine and β-glueuronidase. Again, TMVPLA2 II was more potent than NNAVPLA2. This degranulation effect of mast cells caused by TMVPLA2 II and protamine was inhibited by heparin, while that caused by NNAVPLA2 was unaffected. The edema-forming and mast cell degranulation effects were greatly decreased in both PBPB-modified NNAVPLA2 and PBPB-modified TMVPLA2 II, in which the catalytic activity of the enzymes was completely lost. PBPB-modified TMVPLA2 II-induced paw edema was also suppressed by heparin. Furthermore, this edematous response was totally reversed in rat pretreated with aspirin in combination with diphenhydramine and methysergide. These results suggest that the edema-forming effect of PLA2 is probably dependent on the presence of catalytic, positive charge and pharmacological sites on its molecule.  相似文献   
75.
股骨头缺血性坏死的CT诊断   总被引:3,自引:0,他引:3  
本文报告了19例股骨头缺血性坏死的CT及多平面重建和三维CT成像表现,并探讨其对术前病变评估的价值,在显示Ⅱ期病变时CT明显优于平片,多平面重建有利于发现股骨头塌陷、关节间隙改变和髋臼改变,三维CT可作为一种补充检查手段。  相似文献   
76.
There is a growing body of evidence that the cytokine, tumor necrosis factor-α (TNF-ga), plays an important role in the development of hepatic ischemia/reperfusion injury. We found that the immunosuppressants, cyclosporine-A (CsA), azathioprine, and FK506, have protective effects on such injury. The purpose of the present study was to elucidate mechanisms involved in these beneficial effects of the immunosuppressant, CsA, on liver injury following cold preservation and transplantation, with special reference to the suppression of TNF-α release. Rat livers were stored in Euro-Collins solution (EC) at 4°C for 6h and orthotopically transplanted. The animals allotted to two groups: group A (untreated controls) and group B (CsA pretreatment of recipients). CsA (10 mg/kg, p.o.) was given for 3 consecutive days preoperatively. CsA pretreatment of the recipients significantly improved the 2-week survival rate (0/6 for group A, 3/6 for group B;P<0.05) and this was associated with a significant decrease in serum TNF-α levels 2h posttransplantation (group A, 69.8±15.7 pg/ml; group B, 22.8±6.8; mean±SEM;n=12 each;P<0.05) and amelioration of sinusoidal endothelial injury, assessed by electron microscopy. Plasma endotoxin levels following reperfusion of the grafts were not altered by the CsA therapy. Morphologically, CsA pretreatment of the recipients did not alter activation of Kupffer cells. CsA pretreatment of the recipient aids in preventing cold preservation/reperfusion injury of the liver graft, possibly by modulating effects of TNF-α.  相似文献   
77.
山西省卫Ⅳ项目地区农民因病致贫研究   总被引:4,自引:0,他引:4  
目的 研究项目地区农民因病致贫严重程度及预防措施。方法 利用扩展线性支出系统界定贫困标准,观察因病致贫率并研究因病致贫人群特点。结果 农民因病致贫率3.44%,因病致贫人群收入低,健康状况差,馒性病患病率高。2周就诊和年住院率高,年家庭医疗费用支出远高于对照人群。结论 通过住院医疗保险和慢性病防治措施缓解农民因病致贫。  相似文献   
78.
谈医疗设备漏电对人体的电击   总被引:4,自引:0,他引:4  
医疗设备可以为临床工作提供大量诊断信息和治疗手段,而医疗设备的漏电也会使病人电击灼伤以至危及生命。国务院发布《医疗事故处理条例》以后引起了医疗界高度重视,临床诊疗活动中如何安全使用医疗设备也是预防医疗事故的重要方面。本文着重介绍了电击的种类、对人体的危害及防护措施。  相似文献   
79.
Two elderly women complaining of intermittent claudication complicated with persistent sciatic artery are herein reported. A direct femoral arteriogram showed hypoplasty of the superficial femoral artery and an unnatural anatomical relationship between the distal superficial femoral artery and the proximal popliteal artery, thus suggesting the presence of persistent sciatic artery. The diagnosis of persistent sciatic artery was finally made based on the aortography findings including the iliac arterial system and computed tomography (CT) scan. Magnetic resonance imaging (MRI) was helpful to demonstrate the entire image of this anomaly in cases with non-thrombolized sciatic artery. These diagnostic methods were useful in designing the optimal surgical strategy. The first case with a gluteal pulsating mass underwent exclusion of the persistent sciatic artery including the aneurysm through a retroperitoneal approach with a combination of femorotibial bypass, while the second case with thrombosed persistent sciatic artery only underwent femoropopliteal bypass. To recognize such a rare lesion, awareness of the differential diagnosis is important, and to provide appropriate treatment, an accurate whole image including adequate angiography, a CT scan, and magnetic resonance imaging is necessary.  相似文献   
80.
目的探讨项目记忆和源记忆的神经基础及其是否存在性别差异。方法健康男女各8名,实验材料为504个高频双汉字词,项目记忆和源记忆实验任务,Block设计,GE1.5T采集功能磁共振成像(mRI)数据,用SPM99分析,得到男女脑功能激活图(P〈0.002,体素块〉20)。结果在P〈0.002,体素块〉20时,女性项目记忆激活双前额叶背外侧BA6(激活数目左右侧分别为62和11个),源记忆较多激活左前额叶背外侧BA6/46(激活数目为59个);男性项目记忆激活右前额叶背外侧BA6/46(激活数目为64个),源记忆激活双前额叶背外侧BA6(左右侧分别为9和40个)。结论项目记忆更多激活右侧前额叶背外侧,而源记忆更多激活左侧前额叶背外侧。女性较多地引起左前额叶背外侧激活;而男性较多地引起右前额叶背外侧激活。  相似文献   
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