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971.
972.
Coronary bypass surgery was performed before hospital discharge on 82 (21%) of 386 consecutive patients enrolled in the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) multicenter trial of intravenous tissue plasminogen activator and coronary angioplasty for acute myocardial infarction. Time from infarct symptom onset to coronary bypass surgery was 7.3 +/- 1.9 hours for 24 patients operated upon on an emergency basis and 9.3 +/- 5.2 days for 58 patients having late in-hospital surgery. There were no operative deaths and five in-hospital deaths in the surgical group, all of which occurred in patients with preoperative cardiogenic shock. Although patients in the surgical group were older (59.7 +/- 10.4 years versus 54.9 +/- 10.2 years; p = 0.03), had more extensive coronary artery disease (42% three-vessel disease versus 11%; p = 0.001), and had a higher incidence of anterior wall myocardial infarction (48% versus 39%; p = 0.02), in-hospital mortality for the surgical group (6%) was similar to that in 301 patients not undergoing surgery (7%) in this trial. For patients discharged from the hospital, mortality at 1 year was 2.5% in the surgical group and 1.8% in patients not having coronary bypass surgery before hospital discharge. At a 1 year follow-up, there were no significant differences in the frequency of cardiac or noncardiac-related hospitalizations or in event-free survival between surgical and nonsurgical groups. The majority of patients in both groups considered themselves to be in excellent or good condition. Coronary bypass surgery can be performed with low morbidity and mortality rates in close temporal association to acute myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
973.
974.
The association between alcohol consumption and blood pressure has been studied in 2025 male and 282 female patients undergoing diagnostic coronary angiography. The increase in amount of alcohol consumed correlated with higher systolic and diastolic blood pressure; this effect was especially pronounced in men over 50 years of age. The association was less marked in male patients under 50 years old, in women, and in patients on antihypertensive medication. Readings in the range of definitive hypertension were more prevalent among older patients consuming six or more drinks daily than in abstainers of the same age group.  相似文献   
975.
Spinal cord injury and protection   总被引:5,自引:0,他引:5  
Subsequent to traumatic injury of the spinal cord, a series of pathophysiological events occurs in the injured tissue that leads to tissue destruction and paraplegia. These include hemorrhagic necrosis, ischemia, edema, inflammation, neuronophagia, loss of Ca2+ from the extracellular space, and loss of K+ from the intracellular space. In addition, there is trauma-initiated lipid peroxidation and hydrolysis in cellular membranes. Both lipid peroxidation and hydrolysis can damage cells directly; hydrolysis also results in the formation of the biologically active prostaglandins and leukotrienes (eicosanoids). The time course of membrane lipid alterations seen in studies of antioxidant interventions suggests that posttraumatic ischemia, edema, inflammation, and ionic fluxes are the result of extensive membrane peroxidative reactions and lipolysis that produce vasoactive and chemotactic eicosanoids. A diverse group of compounds has been shown to be effective in ameliorating spinal cord injury in experimental animals. These include the synthetic glucocorticoid methylprednisolone sodium succinate (MPSS); the antioxidants vitamin E, selenium, and dimethyl sulfoxide (DMSO); the opiate antagonist naloxone; and thyrotropin-releasing hormone (TRH). With the exception of TRH, all of these agents have demonstrable antioxidant and/or anti-lipid-hydrolysis properties. Thus the effectiveness of these substances may lie in their ability to quench membrane peroxidative reactions or to inhibit the release of fatty acids from membrane phospholipids, or both. Whatever the mode of action, early administration appears to be a requirement for maximum effectiveness.  相似文献   
976.
A sensitive complement-dependent chromium release cytotoxicity assay was used to determine whether sera from rheumatoid arthritis (RA) patients contain antibody specific for an antigen on rheumatoid synovial cell cultures. Two hundred eight RA sera-RA synovial culture combinations were studied employing 21 sera and 16 synovial membranes; control combinations were derived from 5 normal sera and 10 degenerative joint disease synovial membranes. Anticomplementary activity of some rheumatoid sera was overcome using an increased complement concentration. The percent cytotoxicity of RA serum-RA culture combinations, both homologous and autologous, was not significantly greater than that of RA serum-control culture combinations. No correlation between duration of disease or duration of cell culture and percent cytotoxicity was found. Thus a unique antigen on cultured rheumatoid synovial cells was not recognized by rheumatoid serum antibody by use of this cytotoxicity assay.  相似文献   
977.
Twenty-three patients with total anomalous pulmonary venous connection were studied by two-dimensional echocardiography. In all cases the diagnosis was made before invasive procedures, with surgical or angiocardiographic confirmation. Eleven patients had supracardiac drainage (three to the coronary sinus, two to the right atrium,) and seven had infracardiac drainage. In the majority of cases the precise pattern of drainage could be identified by combining suprasternal, praecordial, and subcostal views. In 12 cases where the suprasternal cut was used a pulmonary venous confluence could be identified, having a cross-like structure in nine, with three others appearing as a dilated channel behind and separate from the left atrium. Thus, two-dimensional echocardiography reliably makes the diagnosis of total anomalous pulmonary venous connection and in the majority the precise pattern of drainage can be determined.  相似文献   
978.
979.
980.
PURPOSE: High-dose therapy and autologous bone marrow transplantation (ABMT) are being increasingly utilized for the management of patients with relapsed Hodgkin's disease. Because patients with relapsed Hodgkin's disease often initially respond to salvage chemotherapy regimens, ABMT is frequently delayed until late in the course of the disease. The optimal timing for ABMT has not been identified. The purpose of this study was to determine the value of ABMT earlier in the course of Hodgkin's disease. PATIENTS AND METHODS: We treated 70 patients between October 1984 and October 1988 with high-dose cyclophosphamide, carmustine, and etoposide, followed by infusion of previously cryopreserved autologous bone marrow, and analyzed the results to determine the impact of timing of ABMT on treatment outcome. One (17 patients), two (24 patients), or three or more (29 patients) chemotherapy regimens had failed in patients before ABMT. RESULTS: The results for all 70 patients included a complete remission rate of 59%, an early death rate of 11%, a 4-year survival of 47%, and 27% of all treated patients alive and in complete remission at 4 years. The median follow-up for patients remaining in complete remission is 56 months (range 26 to 73 months). The frequency of achieving a complete remission was higher in patients in whom fewer regimens had failed before ABMT (i.e., 82% versus 58% versus 45%, p = 0.02), as was the 4-year disease-free survival (i.e., 44% versus 33% versus 21%, p = 0.04). CONCLUSION: ABMT is a more effective therapy when used early for patients with relapsed Hodgkin's disease.  相似文献   
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