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91.
双联抗血小板疗法预防缺血再发   总被引:3,自引:0,他引:3  
本文对应用双联抗血小板聚集药在预防缺血再发方面较应用单药的优势进行了探讨.动脉粥样硬化是一种隐袭性的全身性过程,可累及多处血管床,包括脑动脉、冠状动脉和周围动脉.粥样硬化斑块破裂是血小板活化、聚集和血栓形成进程中的刺激因素之一.因为该病是沿着整个脉管系统发展的,所以对有任何一种动脉粥样硬化临床表现的患者来说,其他血管床也极易受到侵犯.不同的血管病有着共同的易患危险因素.缺血性冠心病和脑血管病是美国三大常见死亡原因中的两种.阿司匹林在心肌梗死和卒中的二级预防方面的有效性已在众多的研究中得到证实.潘生丁在降低心肌梗死、卒中和血管性死亡方面并不比阿司匹林更好,但噻氯匹定和氯吡格雷却明显优于阿司匹林.目前正在进行评估联合应用抗血小板聚集药预防缺血再发的有效性的临床研究.体外试验和临床研究均支持联合应用两种机制不同的抗血小板聚集药的理论.双联应用抗血小板聚集疗法可增强对血小板聚集和血栓形成的抑制作用.联合应用抗血小板聚集药以不同的作用机制抑制血栓形成途径中的多个位点,有可能进一步改善患者远期临床转归.#在预防缺血再发方面,应用双联抗血小板聚集药较应用单药可能更具优势.  相似文献   
92.
The best test presently available to ascertain residual viability within an infarct-related area involves the use of fluorine-18 fluorodeoxyglucose (FDG) to detect the persistence of some cellular metabolism. Rest reinjection of thallium-201 is a less accurate alternative but is easy to perform. Iodinated fatty acids, which are used with standard gamma cameras, are proposed as markers of cellular metabolism. This study was performed to assess the value of 16-iodo-3-methyl-hexadecanoic acid (MIHA) as a marker of the residual cellular metabolism by comparison with FDG in patients with a recent myocardial infarction, and to evaluate its contribution compared with the201Tl stress-redistribution-reinjection technique. Stress-redistribution-reinjection201T1 imaging, rest MIHA imaging and glucoseloaded FDG imaging were performed in 22 patients with recent myocardial infarction. Out of the 628 myocardial segments obtained from the left ventricular analysis, 400 were hypoperfused (relative uptake <0.75 of maximum uptake on stress201T1 imaging), 177 of which were severely hypoperfused (relative uptake <0.50). Receiver operating characteristic (ROC) curves for predicting metabolic myocardial viability with FDG were derived from the results in respect of (a)201T1 activity during exercise, redistribution and reinjection and (b) MIHA up-take, using the two FDG thresholds most commonly considered to define metabolic viability (0.50 and 0.60). Analysis of the 400 hypoperfused segments demonstrated that201T1 reinjection was the most accurate test in predicting the presence of myocardial viability (area under the ROI curves=0.85 and 0.86 at the 0.50 and 0.60 FDG thresholds, respectively;P<0.05 vs other tests). The global predictive values of MIHA and201T1 reinjection were, respectively, 0.87 and 0.89 at the 0.50 FDG threshold (NS), and 0.82 and 0.87 at the 0.60 FDG threshold (NS). When only the 177 severely hypoperfused segments were considered,201T1 reinjection remained the most accurate test (accuracy 0.84 at the 0.50 FDG threshold and 0.82 at the 0.60 FDG threshold), while the accuracy of MIHA decreased significantly (0.78 at the 0.50 FDG threshold and 0.73 at the 0.60 FDG threshold,P<0.05 vs201T1 reinjection). In all circumstances, MIHA was less specific than201T1 reinjection for the detection of metabolic viability. In conclusion, in patients with recent myocardial infarction, MIHA accurately detects the persistence of metabolic viability, but is not superior to201T1.  相似文献   
93.
BACKGROUND: Multiple episodes of rejection following cardiac transplantation have been associated with an increased incidence of coronary atherosclerosis. Total lymphoid irradiation (TLI) has been shown to be a successful treatment for persistent allograft rejection, but its effect on coronary arterial disease has yet to be evaluated. METHODS: From 1987 to 1999, 40 patients required TLI for persistent or recurrent allograft rejection following heart transplantation. Each patient's (Group 1, n = 31) post-transplant coronary angiograms were examined and compared with those of a control group (Group 2, (n = 32) matched for time of transplantation. Degree of coronary stenosis was assessed on a 6-point scale. All patients received induction therapy (rabbit anti-thymocyte globulin or OKT3) and standard triple immunosuppressive therapy. TLI (80 cGy x 10 fractions) was used for the treatment of recurrent or persistent rejection on the basis of clinical indications. Actuarial survival, number and treatment of rejection episodes, and severity of coronary artery disease were compared in each group. RESULTS: Recipient gender, age, race and cytomegalovirus (CMV) status at time of transplant, along with donor gender, CMV status and graft ischemia time, were similar in both groups. Group 1 donor age was younger than that of Group 2 (22.2 +/- 11.2 vs 31.5 +/- 13.6 years, p = 0.004), and the indication for surgery in Group 1 patients was more likely to be ischemic heart disease (15 of 31 vs 6 of 32, p = 0.02). Mean follow-up was 5.7 +/- 3.5 years in Group 1 vs 6.9 +/- 3.8 in Group 2 (p = NS). Group 1 had more rejection episodes (4.4 +/- 2.2 vs 2.3 +/- 2.0, p = 0.0002) and more steroid treatments (9.78 +/- 4.0 g vs 5.14 +/- 4.7 g, p < 0.0001), but less coronary artery disease compared with Group 2 (p = 0.035). CONCLUSIONS: Despite multiple episodes of rejection, patients treated with TLI after cardiac transplant appear to develop less coronary atherosclerosis than appropriately matched controls.  相似文献   
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Sir, In a recent Indian serosurvey [1], it was announced that ‘noreports of hantavirus infections in humans from India existed[before 2005]’. We wish to point out that serologicaland clinical evidence of hantavirus infection in India was alreadywell documented before 2005. From 1998 on, we screened leptospirosis-suspected cases in Indiafor the only known cosmopolitan hantavirus serotype, Seoul virus(SEOV). Wild rats are the reservoir  相似文献   
97.
The author focuses attention or institutional psychotherapy and draws its clinical, philosophical and also ethical concepts in order to prove that an administrative logic of the mental institutions only leads to loose what characterise healing process. Three main axis are tackled: the concept of reaction, the concept of pathoplasty and the concept of alienation. The concept of reaction makes understandable how the atmosphere of an institution is exercising a so great influence on its patients' symptoms that a self-governing endogenic psychopathological process “that is turned away from its initial cause” is created. That results in the concept of pathoplasty, which refers to the fact that some aspects of the pathology are induced by the institution itself, from which result two main ideas of the institutional psychotherapy: a) an institution is to tie down to an auto analysis to heal its own pathological functioning; b) all the more so that an institution which doesn't could become iatrogenic. The concept of alienation is approached through the historical and philosophical aspects of the Marxist view. The author use Bataille's differentiation between restricted economy “which is in keeping with a capitalist one, susceptible of an accountable evaluation” - and general economy - which confus to negativity as a foundation for an inner social work, apart from any accountable evaluation to Hegel's mind for instance, desire is indissociable from the psychiatric heal.  相似文献   
98.
OBJECTIVE: One of the complications of CPB is the systemic inflammatory response syndrome (SIRS). Recent developments tend to minimize the biological impact of CPB in using miniaturized closed circuit with reduced priming volume and less blood-air interface. The benefit of these miniaturized closed circuits in terms of inflammatory response has been proved in coronary surgery. However, in open heart surgery, the CPB circuit is no more closed and the benefit of the miniaturized set-up could disappear. The aim of the study is to compare the SIRS between standard and miniaturized circuits in aortic surgery. METHODS: Forty patients who underwent singular aortic valve replacement were randomly assigned either to a standard CPB (group A, n=20) or to a miniaturized CPB (group B, n=20). Pertinent clinical and surgical data were collected. Hematological parameters (leukocyte and neutrophil counts) and biochemical parameters (C-reactive protein, cytokine tests) were determined pre-, on and post-CPB. RESULTS: There were an increase in leukocyte and neutrophil counts and a decline in hematocrit in both groups. In both groups, there was a raise after CPB, in C-reactive protein, IL-6, TNF-alpha, neutrophil elastase, and IL-10. However, the raises of elastase and TNF-alpha were significantly lower after the weaning of miniaturized CPB (116+/-46 ng/ml and 10+/-4 pg/ml, respectively) compared to standard CPB (265+/-120 ng/ml, P=0.01 and 18+/-7 pg/ml, P=0.03). The raise of IL-10 is also lower with miniaturized circuit (15+/-6 pg/ml) compared to standard circuit (51+/-26, P=0.004). CONCLUSIONS: This study demonstrates in aortic surgery, the lesser inflammatory response of a miniaturized CPB compared to a standard CPB. However, there is always some inflammation after CPB and a small bio-reactive free perfusion circuit is still to be found in open heart surgery.  相似文献   
99.
OBJECTIVE: To determine how knowledgeable physicians are regarding the toxic effects and drug interactions of herbal remedies. METHODS: An anonymous voluntary demographic survey and 16-question, multiple-choice quiz was distributed at educational meetings of emergency medicine and internal medicine physicians. The primary outcome measures were to determine whether significant associations existed between quiz scores and the amount of clinical experience, or between quiz scores and self-assessed familiarity with the topic of herbal toxicities and adverse herb-drug interactions. RESULTS: A total of 142 surveys and quizzes were completed by 59 attending physicians, 57 resident physicians, and 26 medical students. The mean subject score on the quiz was only slightly higher than would have occurred from random guessing. Neither the amount of the subjects' clinical experience, nor their self-assessed familiarity with herbal toxicities and drug interactions correlated significantly with the score on the quiz. CONCLUSION: The physicians and medical students surveyed had little training in herbal toxicities and drug interactions. They generally rated their familiarity with these topics as 'poor', and their scores on the quiz bore out this assessment as correct. Educational efforts might improve physician knowledge of the adverse effects of herbal remedies.  相似文献   
100.
This study validates a new quantitative myocardial perfusion SPECT software. METHODS: The processing starts with the extraction of the morphologic skeleton of the left ventricular myocardium from reconstructed transverse sections. Fuzzy logic is used to decide whether a pixel belongs to the myocardium and any perfusion defect is filled according to a truncated bullet model. The resulting image is partitioned in 18 isovolumetric sectors. Sex-matched normal limits, criteria of abnormality for rest (201)Tl and (99m)Tc-labeled perfusion tracers, reproducibility studies, and detection of coronary artery disease were developed and validated in an overall population of 343 patients. The sex- and tracer-matched means and SDs of a normal response were calculated in 93 male and 93 female patients with a <5% likelihood of coronary artery disease. Reproducibility measurements and assignment of different sectors of the myocardium to a specific coronary were performed from data collected in 49 and 60 patients, respectively. The accuracy of the detection of a coronary artery occlusion was assessed in 48 patients who also underwent coronary angiography. RESULTS: The intra- and interoperator reproducibility of the sectorial activity was high with a linear regression coefficient of 0.97 and a SD of the difference measurement at 4.4% and 3.8%, respectively. Overall sensitivity and specificity for the detection of occluded coronary artery were 90% and 80%, respectively. For the detection of left anterior descending, left circumflex, and right artery coronary occlusion, sensitivity was 92%, 75%, and 92.5%, respectively, and specificity was 75%, 78%, and 90%, respectively. CONCLUSION: The new quantitative myocardial perfusion SPECT software appears to be a very helpful program for the objective analysis of perfusion tracer distribution in myocardial SPECT and a very accurate tool in the detection and localization of coronary artery occlusion.  相似文献   
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