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排序方式: 共有1667条查询结果,搜索用时 421 毫秒
1.
Does off-pump coronary artery bypass reduce the incidence of post-operative atrial fibrillation? A question revisited. 总被引:3,自引:0,他引:3
Thanos Athanasiou Omer Aziz Omar Mangoush Sharif Al-Ruzzeh Sujit Nair Vitali Malinovski Roberto Casula Brian Glenville 《European journal of cardio-thoracic surgery》2004,26(4):701-710
Atrial fibrillation (AF) is the most common post-operative complication in patients undergoing coronary artery bypass grafting, with an increased incidence associated with advancing age. This study aims to determine whether off-pump coronary artery bypass (OPCAB) reduces the incidence of AF in a generalized population (mean age <70 years). A meta-analysis was performed including all randomised and propensity score matched non-randomised studies published between 2001 and 2003 reporting a comparison between the two techniques in a generalised patient group (average age <70 years). The primary outcome of interest was post-operative AF. Sensitivity analysis was performed to evaluate consistency of the calculated treatment effect. Fourteen studies fulfilled our inclusion criteria, including a total of 16,505 subjects. The incidence of AF was 19% (1612/8265) in the off-pump group versus 24% (1976/8240) in the on-pump group. When considering only the 11 randomised studies (2207 subjects), we found a significant reduction in the incidence of post-operative AF in the off-pump group using a random-effect model (odds ratio (OR)=0.60, 95% confidence interval (CI)=0.45-0.82, and chi-square of heterogeneity=18.02, P=0.05). Sensitivity analysis highlighted one randomised study causing funnel plot asymmetry, exclusion of which resulted in a significant reduction in the incidence of post-operative AF in the off-pump group (OR=0.71, 95% CI=0.57-0.90), with a non-significant heterogeneity of 3.91 (P=0.92). When only studies of high quality were considered (898 patients), no significant difference was seen between on and off-pump groups (OR=0.78, 95% CI=0.57-1.07, and heterogeneity=0.53, P=0.91). This may be due to small number of patients in this group. Our results suggest that although OPCAB surgery may reduce the incidence of post-operative AF in a generalised population (age <70 years) this finding is not clearly supported by high quality randomised trials. Although previous evidence suggests that the incidence of post-operative AF is reduced in an elderly population (>70 years) with off-pump surgery, our results show that the evidence is less clear in a younger population group. The question of whether off-pump surgery in this patient group results in a lower rate of post-operative AF remains to be answered by further high quality randomised research. 相似文献
2.
Blood flow of the areola and breast skin flaps during reduction mammaplasty as measured by laser Doppler flowmetry. 总被引:6,自引:0,他引:6
Blood flow changes during reduction mammaplasty were studied using laser Doppler flowmetry. Twenty-one patients (39 breasts) were entered into the study. Eight patients underwent a modified Skoog mammaplasty, 6 a central glandular pedicle mammaplasty, 2 an inferior pyramidal dermal flap mammaplasty, and 5 a glandular resection with free nipple grafts. Laser Doppler flowmetry was performed preoperatively, immediately postoperatively, 24 hours postoperatively, 48 hours postoperatively, and 2 weeks postoperatively. Laser Doppler flowmetry values (in milliliters per minute per 100 grams) measured at the areola declined by 23% (Skoog), 18% (central pedicle), and 21% (inferior pyramidal), in the immediate postoperative period. Values at 48 hours were 31% below baseline (Skoog), 14% below baseline (central pedicle), and 60% below baseline (inferior pyramidal). Values at 2 weeks postoperatively were 12% below baseline (Skoog), 2% above baseline (central pedicle), and 44% below baseline (inferior pyramidal). The free nipple grafts showed an 89% rise above baseline at 2 weeks. One patient's procedure was changed to a free nipple graft after a 92% Doppler flow reduction during a Skoog mammaplasty. The free nipple graft had the greatest blood flow. The central pedicle mammaplasty showed the least decline in areolar flow. The inferior pyramidal mammaplasty showed the greatest decline. Laser Doppler flowmetry is a clinically useful tool for monitoring intraoperative and postoperative nipple/areolar blood flow. 相似文献
3.
W Bencivelli C Vitali D A Isenberg J S Smolen M L Snaith M Sciuto S Bombardieri 《Clinical and experimental rheumatology》1992,10(5):549-554
In the first phase of this study, a data-base containing clinical and laboratory findings of 704 patients with systemic lupus erythematosus (SLE), originating from 29 centres and 14 countries, was used to assess the validity of 4 common indices of disease activity, SLAM, BILAG, SLEDAI and SIS. The physician's judgement of activity was assumed as the unique reference criterion (gold standard). Computer programmes were developed to calculate automatically the 4 activity indices; this computation appeared to correspond with manual computations in a sample of 60 appropriately selected cases. All 4 indices were closely correlated with each other (r in the range of 0.716 to 0.872), and with the physician's score (r in the range of 0.620 to 0.719). In the second phase of the study the activity index developed in part I (ECLAM) was prospectively validated, and its performance compared to that of the other scales, both as a single state index and as a transition index (i.e., its ability to assess disease activity at a single point in time and to detect variations in consecutive readings). A computer-assisted clinical chart was prepared for this purpose. This chart allowed us to calculate automatically all the indices. Two consecutive observation times (time 0, and time 1 three months later) were included in the study protocol. Data on 75 patients from 19 centres were collected, and each patient was observed twice. All the computed indices were closely correlated, both at time 0 (r ranging from 0.725 to 0.884), and at time 1 (r ranging from 0.607 to 0.833).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
We present the results of a prospective study comparing the accuracy of magnetic resonance imaging with arthroscopy in the assessment of knee complaints. Using a low field strength magnet, MRI was able to achieve a high diagnostic accuracy within the setting of a district general hospital. 相似文献
5.
Effect of budesonide on pulmonary hyperinflation in young asthmatic children. 总被引:1,自引:0,他引:1
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In 19 asthmatic children, aged 2-6 years, the effect of six weeks' treatment with inhaled budesonide or placebo on functional residual capacity (FRC--helium dilution) and bronchodilator responsiveness was assessed in a double blind, randomised crossover trial. FRC was increased in most children at the start of treatment. Treatment with budesonide was associated with a reduction in FRC by comparison with placebo (median change 9% v 0%; p less than 0.05). There was a trend towards a greater response to a bronchodilator after budesonide. The results suggest that inhaled corticosteroids reduce hyperinflation in young asthmatic children. 相似文献
6.
E De Paoli Vitali C Guglielmini I Casoni M Vedovato P Gilli A Farinelli G Salvatorelli F Conconi 《International journal of sports medicine》1988,9(2):99-101
Serum erythropoietin (Epo) activity, hemoglobin (Hb), and hematocrit (Ht) were determined in 21 cross-country skiers during the training season. The Epo levels were not significantly reduced in the skiers relative to the normal population (P less than 0.01 and P less than 0.001, respectively). In 11 athletes Epo, Ht, urinary gamma-glutamyltransferase, N-acetyl-beta-glucosaminidase, and microalbuminuria were determined before and after a 50-km ski race at 1600 m above sea level. A significant increase of these variables (except for Ht) was found after the competition (P less than 0.001). It is concluded that while the reductions in Hb and Ht, which are typical of several endurance exercises, are not accompanied by a renal hypoxia sufficient to stimulate Epo overproduction, the renal hypoxia reached during the strenuous exercise of the race at altitude may be effective in determining blood increases in Epo. 相似文献
7.
J. A. P. van de Nes A. A. Sluiter C. W. Pool W. Kamphorst R. Ravid D. F. Swaab 《Brain research》1994,655(1-2)
The monoclonal antibody Alz-50 is directed against Alzheimer's disease-related modified tau proteins and reveals cytoskeletal changes, i.e. neurofibrillary tangles and dystrophic neurites. The present study shows that, in the hypothalamus of non-demented control subjects, this same antibody gives a distinctive staining pattern of a subpopulation of somatostatin neurons and beaded fibers. Furthermore, Alz-50 occasionally recognizes somatostatin-containing cell bodies and dystrophic neurite-like fibers in the (neuritic) senile plaques of AD patients. These observations have direct consequences for the interpretation of Alz-50 staining in diagnostic usage and for the assessment of Alzheimer's disease-like changes induced by β-amyloid in experimental animal brains. On dot spotting, Alz-50 was found to bind to a number of fragments from the somatostatin precursor, of which somatostatin15–28 stained best. Preadsorption of Alz-50 by somatostatin15–28, as well as other specificity tests, failed, however, to provide any clue to the nature of the unknown compound(s) stained in the control hypothalamus. 相似文献
8.
9.
Robert F Bonvini Ulrich Sigwart Vitali Verin 《Catheterization and cardiovascular interventions》2007,69(2):274-276
We report the case of a 36-year-old woman admitted for cryptogenic stroke, in whom the Patent Foramen Ovale (PFO) diameter measurement, with a purpose built sizing balloon, performed before the closure procedure, was complicated with the rupture of the inter-atrial septum generating an Atrial Septal Defect (ASD) with a significant left-to-right shunt. This kind of complication may not be easy to handle, changing the initial procedural strategy from PFO to ASD closure technique requiring specific material and operator's technical skill. 相似文献
10.
S Ricci M G Celani G Guercini P Rucireta R Vitali F La Rosa E Duca R Ferraguzzi M Paolotti D Seppoloni 《Stroke; a journal of cerebral circulation》1989,20(7):853-857
The SEPIVAC study (Italian initials for "epidemiologic study of incidence of acute cerebrovascular disease") is a community-based epidemiologic survey of incidence and outcome of cerebrovascular disease in the territory of the 6th Local Health Unit, Umbria, Italy, where 49,101 people live. All cases were registered with the study either by notification from general practitioners or by check of hospital admission within the study area and in the two hospitals of Perugia. Death certificates were looked at as well. Patients were registered with the study when the clinical picture fulfilled the definition of stroke and transient ischemic attack (TIA) adopted for this study. Patients were followed up at approximately 30 days and 6 months. During the first year of the study (September 1, 1986 to August 31, 1987), 189 cases were registered: 108 suffered a "first ever in a lifetime" stroke, 30 a recurrent stroke, and 51 a "first ever in a lifetime" transient ischemic attack. Sixty-one percent of patients (71% of first strokes) had a computed tomography scan. For our study, the crude annual incidence rate of first stroke was 2.2 per 1,000 (confidence intervals 1.81-2.66); the standardized rate to the European population was 1.36 (confidence intervals 1.06-1.74). At least 83% of first strokes were due to cerebral ischemia; in 26 cases a clinical diagnosis of lacunar ischemia was made. The 30-day case fatality rate was 21%; 25% of our patients had recovered completely or almost completely after 1 month. 相似文献