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排序方式: 共有245条查询结果,搜索用时 31 毫秒
21.
Persistent improvement after coronary bypass surgery: ergometric and angiographic correlations at 5 years 总被引:2,自引:0,他引:2
One hundred patients with angina pectoris who fulfilled specific entry criteria were randomly assigned to either medical therapy or bypass surgery. These groups were subjected to annual exercise testing during a 5-year follow-up period. The degree of revascularization was assessed by graft and native vessel angiography at 3 weeks, 1 year and 5 years after the operation. The exercise tolerance of the medical group remained largely unchanged during the follow-up. Eighty-five to 95% of the patients were using beta-blocking compounds at the successive testing situations. The surgical group exhibited a sustained improvement in exercise tolerance: Total work increased by 39-66% (p less than 0.02-0.001) and maximal ergometric load by 23-35% (p less than 0.01-0.001), and maximal ST depression decreased by 39-61% (p less than 0.05-0.001). The use of beta-blocking compounds in the surgical group steadily increased, from 44% at 6 months after operation to 63% of patients at 5 years. Division of the surgical group into subsets of complete and incomplete revascularization revealed that the improvement was confined to complete revascularization. Thus, the improved exercise tolerance after bypass surgery was a result of successful reestablishment of effective coronary perfusion; despite graft attrition (15% in 5 years) and new lesions in the native arteries, this improvement persisted for 5 years with appropriate medical therapy. 相似文献
22.
The Kheda project experience has shown that bio-environmentalcontrol of malaria is feasible, cost effective and ecologicallysound. It clearly brings out the need to consider health issuesat the planning stage of all developments. Bio-environmentalcontrol of malaria is suggested as the first line of attackfor the control of mosquitoes, malaria and other mosquito-bornediseases. Insecticides may be reserved for short-term use. Thiswill enable judicious and selective use of insecticides in solelyepidemic situations. The growing problem of resistance to insecticidesin mosquitoes as well as environmental pollution, can then besolved on a long term basis. 相似文献
23.
Preservation of venous valve function after catheter-directed and systemic thrombolysis for deep venous thrombosis. 总被引:7,自引:0,他引:7
M K Laiho A Oinonen N Sugano V-P Harjola A L Lehtola W-D Roth P E Keto M Lep?ntalo 《European journal of vascular and endovascular surgery》2004,28(4):391-396
OBJECTIVES: The aim of the study was to assess venous reflux and the obstruction pattern after catheter-directed and systemic thrombolysis of deep iliofemoral venous thrombosis. PATIENTS: Thirty-two patients treated either with systemic (16) or catheter-directed local thrombolysis (16) for massive iliofemoral thrombosis were identified from the hospital registry. METHODS: Clinical evaluation at follow up was based on the CEAP classification and disability score. Reflux was assessed by colour duplex ultrasonography and standardised reflux testing. A vascular surgeon blinded to treatment established the clinical status of the lower limb following the previous DVT. RESULTS: Valvular competence was preserved in 44% of patients treated with catheter-directed thrombolysis compared with 13% of those treated with systemic thrombolysis (p=0.049, Chi squared). Reflux in any deep vein was present in 44% of patients treated by catheter-directed lysis compared with 81% of patients receiving systemic thrombolysis (p=0.03, Chi squared). Reflux in any superficial vein was observed in 25% vs. 63% of the patients, respectively (p=0.03, Chi squared). There were significantly more patients with venous insufficiency of classes C0-1 in the group treated with catheter-directed thrombolysis. CONCLUSION: In this clinical series venous valvular function was better preserved after iliofemoral DVT when treated with catheter-directed thrombolysis. 相似文献
24.
研究背景和目的
在急诊救治的过程中最重要的就是快速建立静脉通道,以补充体液、给药以及输血等.但是,由于皮下结构(如血管深度、脂肪组织、皮肤色素、血管内血容量)的复杂性,往往阻碍了肉眼下静脉穿刺过程的实施.血管超声可以辅助寻找相对较粗的静脉,但是此设备和技术的要求较高,影响了其在临床的广泛应用;可见光透射法所得结果不甚可靠,且容易造成灼伤.红外成像时由于其穿透深度较可见光深,而且血液对红外光能量的吸收明显高于脂肪和黑色素等血管周围组织,因而可以得到对比度清晰的图像.…… 相似文献
25.
Abstract. The susceptibility of cultured rat kidney parenchymal components to natural killer (NK) cell and lymphokine-activated killer (LAK) cell-mediated lysis in a 4-h in vitro 51 chromium assay was investigated. Large granular lymphocytes (LGL) in the spleen and in the kidney allograft were able to lyse YAC cells during rejection, but they did not damage target endothelial, glomerular mesangial, glomerular epithelial, or tubular cells in resting state. Stimulation of the target cells with gamma-interferon - known to induce MHC (class II) antigens on the target cell surface - did not make the target cells susceptible to NK-mediated lysis. LAK cells generated by a 3-day incubation with interleukin-2 (IL-2) effectively lysed both YAC and P815 target cell lines. LAK cells were also slightly cytotoxic to all tested parenchymal target components in resting state. Gamma-interferon treatment of the cultured parenchymal cells prior to the chromium release assay, however, reduced LAK-mediated parenchymal cell cytotoxicity to nearly nondetectable levels. Obviously, many lymphokines, including IL-2 and gamma-interferon, are produced during rejection at the site of inflammation. This might induce the generation of LAK cells in situ as the lymphokines induce the production of MHC antigens in the graft. We interpret these findings as indicating that regardless of the generation of LAK, the protective effect of gamma-interferon neutralizes the LAK effect, and we suggest that neither LGL nor LAK cells play any essential role in rat kidney allograft rejection. 相似文献
26.
27.
M Konttinen P T Harjola M Heinonen M Valle E Merikallio M H Frick 《Annales chirurgiae et gynaecologiae》1985,74(6):265-269
The direct hospital costs of 100 coronary artery bypass grafting operations are calculated. The basis of the calculations is the detailed, function-based, market-priced analysis of the files, including the hospital deaths, complication and reoperations of this patient group. The price of a CABG operation proved to lie somewhere between FIM 30,000 and 50,000, the mean value being FIM 46,800. The variation range is wide: FIM 18,200-FIM 249,500 (SD +/- FIM 26,000). It must be emphasized, however, that all preoperative hospital costs including coronary angiography costs and also postoperative follow-up hospital costs fall beyond this study. 相似文献
28.
Dave VP; Keefe R; Berger MA; Drbal K; Punt JA; Wiest DL; Alarcon B; Kappes DJ 《International immunology》1998,10(10):1481-1490
CD3delta-deficient (delta degrees) mice are defective in alphabeta T cell
development. Here we explore the capacity of TCR-CD3 signaling complexes
expressed on delta degrees thymocytes to mediate the following functional
outcomes in response to antibody cross-linking: (i) the transition from the
CD4-CD8- to CD4+CD8+ stage, (ii) the transition from the CD4+CD8+ to
CD4+CD8- or CD4-CD8+ stages and (iii) the induction of apoptosis. We
provide evidence that CD3deltaepsilon complexes are dispensable for
mediating the anti-CD3-mediated CD4-CD8- to CD4+CD8+ transition. On the
other hand, CD3delta is critical at the CD4+CD8+ stage. We demonstrate that
CD4+CD8+ thymocytes from delta degrees mice, unlike delta degrees CD4-CD8-
thymocytes and wild-type CD4+CD8+ thymocytes, require prolonged or
consecutive stimuli to elicit functional responses. Depending on the nature
of the secondary stimulus, delta degrees thymocytes can be induced to
undergo apoptosis or preferential maturation to the CD4-CD8+ stage. Taken
together these results indicate that the signaling capacity of the TCR-CD3
complex is noticeably altered in the absence of CD3delta. The essential
role of CD3delta at the CD4+CD8+ stage of development correlates with the
onset of TCRalpha rearrangement, consistent with a critical structural
and/or functional relationship between CD3delta and TCRalpha.
相似文献
29.
P T Harjola K H?ckerstedt T M Scheinin C G Standertskj?ld-Nordenstam E T?hti 《The Journal of cardiovascular surgery》1975,16(6):626-631
The Mobin-Uddin umbrella filter was placed into the inferior vena cava of mongrel dogs. Studies on hemodynamics and embolization were performed using blood flow and pressure determinations, cineangiography, and radiopaque emboli. Initially flow and pressure remained unaffected by the filter. At 70 minutes flow was only one fourth of the initial IVC flow. Immediately after positioning of the filter emboli up to 6 mm in diameter bypassed the filter, and smaller emboli passed through the perforations in the filter. Thrombus formation on the surface of the umbrella was already noted within one hour. At autopsy after two hours all the perforations were occluded by thrombus on both sides of the filter, and one week later the infrarenal vena cava was completely occluded by firm organized thrombus below and above the filter. 相似文献
30.