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排序方式: 共有5731条查询结果,搜索用时 15 毫秒
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J G Byrne R F Appleyard C C Lee G S Couper F G Scholl R G Laurence L H Cohn 《The Journal of thoracic and cardiovascular surgery》1992,103(1):66-71; discussion 71-2
Open-chest sheep underwent 90 minutes' occlusion of the diagonal branch of the left anterior descending coronary artery, followed by vented cardiopulmonary bypass. After 30 minutes of cardioplegic arrest, simulating distal anastomoses, the occlusion on the coronary artery branch was released. Controlled reperfusion (40 to 50 mm Hg, 135 to 150 ml/min) for the first 20 minutes was delivered at the aortic root with either unmodified whole blood (control, n = 7) or blood passed through leukocyte filters (filters, n = 7). Serial measurements were made during 3 additional hours reperfusion off cardiopulmonary bypass. During ischemia, the major determinants of infarct size, which include area at risk, collateral myocardial blood flow, and rate-pressure product were not significantly different between groups. Overall, during reperfusion, mean left ventricular stroke work index in the filter group was greater than in the control group (28.7 +/- 5.8 versus 12.6 +/- 6.4 x 10(3) erg/gm, p less than 0.05), as was mean rate of rise of left ventricular pressure (1900 +/- 260 versus 1348 +/- 279 mm Hg/sec, p less than 0.05). Myocardial blood flow to the area at risk at 3 1/2 hours of reperfusion in the filter group was also significantly better than in the control group (0.57 +/- 0.15 versus 0.27 +/- 0.05 ml/min/gm, p less than 0.05), as was necrotic area as a percentage of area at risk (40% +/- 6% versus 70% +/- 5%, p less than 0.05). These results demonstrate amelioration of myocardial stunning and the no-reflow phenomenon, as well as decreased infarct size. We conclude that controlled reperfusion with leukocyte-depleted blood is superior to whole-blood reperfusion for the surgical treatment of acute regional ischemia. 相似文献
33.
Gangliosides of cultured astroglia 总被引:3,自引:0,他引:3
Michele Sbaschnig-Agler Henri Dreyfus William T. Norton Monique Sensenbrenner Muhammad Farooq Mary C. Byrne Robert W. Ledeen 《Brain research》1988,461(1):98-106
Cultured astrocytes prepared from newborn rat brain and 13-day-old chick embryonic brain were analyzed qualitatively and quantitatively for ganglioside content. All preparations contained approximately the same total level: 2.4-3.4 micrograms N-acetylneuraminic acid (NeuAc)/mg protein. In contrast, the value for primary cultures of neurons from chick embryonic brain was 5.9. The non-hexosamine-containing species, GM3 and GD3, comprised 75-85% of the total in astroglial cultures, the remainder consisting mainly of structural types other than the gangliotetraose series; choleragenoid assay revealed the latter to be virtually absent or to comprise at most a few percent. Deficiency of gangliotetraose synthesizing ability was indicated by the very low level of UDP-GalNac:GM3 N-acetylgalactosaminyltransferase detected in the cells. Treatment of cultured astrocytes with astroglial growth factor 2 or dibutyryl cyclic AMP caused little if any change in quantity or pattern of gangliosides. The large majority of cells stained in a manner characteristic of astrocytes: positive for glial fibrillary acidic protein, negative for galactosyl ceramides. Staining with cholera toxin and anti-GM1 antibody was essentially negative, as was that with tetanus toxin, A2B5 monoclonal antibody, and antibody to GD3. All evidence thus points to cultured astrocytes of rat and chick brain containing appreciable gangliosides, most of which are GM3 and GD3 with the majority of the remainder comprising structures other than the gangliotetraose type. 相似文献
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Three dimensional computed tomographic imaging in planning the surgical approach for redo cardiac surgery after coronary revascularization. 总被引:2,自引:0,他引:2
Hrvoje Gasparovic Frank J Rybicki John Millstine Daniel Unic John G Byrne Kent Yucel Tomislav Mihaljevic 《European journal of cardio-thoracic surgery》2005,28(2):244-249
OBJECTIVE: Reoperative cardiac surgery after previous coronary artery bypass grafting represents a surgical challenge due to the potential for injury to patent coronary grafts, aorta or right ventricle. Standard preoperative imaging using a coronary angiogram and chest radiograph (CXR) often results in inaccurate assessment of mediastinal anatomy. We aimed to evaluate 3D volume rendered computed tomographic imaging as an adjunct to standard preoperative assessment of patients requiring cardiac surgery in whom coronary artery revascularization had been performed in the past. METHODS: Between January 2003 and January 2004, 33 patients with previous coronary revascularization referred for reoperative cardiac surgery underwent preoperative 3D CT imaging in order to optimize the surgical approach. The mean age in this patient population was 72+/-8 years. The combined evaluation of CXR and conventional angiography offered incomplete insight into pertinent mediastinal topography in 85% of patients (28/33). RESULTS: The correlations for distances of the left internal mammary artery (LIMA) to left anterior descending artery (LAD) graft from the midline and posterior sternum obtained by CT angiography (CTA) and CXR were poor, R=0.56 and 0.49, respectively. The correlation coefficients for distances between the right ventricle and the aorta to the sternum obtained by the same methods were similarly marginal, 0.58 and 0.48, respectively. The correlation coefficients for distances between the LIMA to LAD, circumflex and right coronary artery grafts from the midline obtained by CTA and conventional angiography were 0.54, -0.13 and 0.43, respectively. In seven patients (21%) the surgical strategy was modified based on the location of patent grafts in the mediastinum. The hospital mortality was 17% (5/29). Intraoperative injuries to vital structures were encountered in two patients (7%). No injuries to patent LIMA or the aorta were encountered. CONCLUSIONS: The 3D CT imaging technique is useful in defining the optimal surgical strategy for reoperative cardiac surgery. We found that CTA is superior to CXR and conventional angiography in defining the position of patent grafts and vital structures in relation to the midline and posterior sternum. Preoperative mapping of patent coronary grafts and other vital mediastinal structures reduces the morbidity of the reoperation through modification of surgical approaches. 相似文献
36.
Karina L Allen Susan M Byrne Eve M Blair Elizabeth A Davis 《International journal of pediatric obesity》2006,1(4):239-247
OBJECTIVE: To examine the associations between weight status, weight and shape concern, self-esteem, body dissatisfaction and depression in children. METHODS: Interviews were conducted with 7- to 13-year-old overweight (n = 89) and healthy weight (n = 118) children, using the Child Eating Disorder Examination, Self-Perception Profile for Children, Children's Body Image Scale and Child Depression Inventory. RESULTS: Overweight children were more concerned about weight and shape than healthy weight children. After controlling for BMI z-score, children with high weight and shape concern reported lower self-esteem, higher body dissatisfaction and higher depression than children with low weight and shape concern. Concern about weight and shape mediated the relationships between BMI z-score and low self-esteem, body dissatisfaction and depression. CONCLUSIONS: Results support the hypothesis that differences in weight and shape concern, within samples of overweight and healthy weight children, can account for differences in degree of psychological distress. Findings have implications for the prevention and treatment of psychological problems in overweight children. 相似文献
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SUMMARY Elevated plasma levels of Lp(a) do seem to influence the progression of atherosclerosis. Evidence is emerging that certain apo(a) isoforms may be more atherogenic than others, and in transgenic mice free apo(a) has been shown to be associated with accelerated atherosclerosis. Currently it is not known whether treating elevated Lp(a) levels will reduce progression of atherosclerosis and, as therapeutic options are limited, mass screening of Lp(a) levels in populations is not indicated. The presence of raised Lp(a) levels, however, warrants aggressive treatment to reduce other cardiovascular risk factors. Continuing research to investigate the relationship of the apo(a) gene to other genes, including the plasminogen gene and apo(a)-related genes, will add further information pertaining to the evolution, function, regulation and clinical implications of Lp(a). 相似文献
40.
Mark Sanford Carolyn Byrne Susan Williams Sandy Atley Jennifer Miller Heather Allin 《Revue canadienne de psychiatrie》2003,48(2):78-86
OBJECTIVE: This study assessed the feasibility and efficacy of a parent-education group for families with young children and a parent with depression. We designed the program to be readily disseminated if shown to be effective. METHOD: We recruited 44 parents with depression from clinics and family doctors in Hamilton, Ontario, and randomly assigned them to receive the parenting program or to a wait-list control group. The outcomes measured included knowledge of depression, parenting, family relationships, depression symptoms, child depressive symptoms, and functioning. We used analysis of covariance to test for posttreatment differences between experimental and control groups. RESULTS: Of the treatment group, 27% dropped out at posttreatment, and 43% by follow-up. Those who dropped out had more severe depression at baseline than did those who completed the program, and there was selective loss of parents with more severe depression in the experimental group. In intention-to-treat analyses at posttreatment, probands in the experimental group reported more improvements on family functioning, parenting sense of competence, and family and parent conflict than did control subjects. Standardized effect sizes (ES) were medium (0.4 to 0.6). When baseline depressive symptom scores were controlled in the analyses, the between-group differences were reduced, showing that selective loss of participants may have influenced the findings. CONCLUSIONS: On balance, the results are encouraging and support the further development and evaluation of the group intervention. However, the study does not provide unequivocal evidence in support of the program. Before it is transferred to other settings, the program needs further modification to improve participation by parents with more severe depression and further evaluation of its effectiveness. 相似文献