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41.
Success of meniscal repair with early or immediate motion depends on the ability of the suture fixation to withstand the loads applied. Vertical and horizontal mattress suture techniques were tested using 2-0 Ethibond, and 0-PDS and 1-PDS sutures (Ethicon, Somerville, NJ). Mulberry knot technique was tested with 0-PDS and 1-PDS sutures. Twenty menisci (60 sutures) were tested for each suture material. Sutures were placed 3 to 4 mm from the peripheral edge of the meniscus with double barreled cannulas for vertical and horizontal mattress techniques or a spinal needle for the mulberry knot technique, reproducing clinical techniques of meniscal repair. Mechanical testing of suture fixation was performed to failure at a rate of 10 mm/min on a MTS material testing system (MTS Systems Corp. Minneapolis, MN). Suture pullouts were reported as the load displacement to failure from the inner fragment only, because clinical failure would ensue should a suture pull through the inner fragment of a tear. Vertical mattress technique with 1-PDS suture had significantly greater load to failure than any other combination (P < .05). Analysis of variance showed that the vertical mattress technique had statistically superior pullout strength (P < .0001) compared with the horizontal mattress and mulberry knot techniques, which were statistically similar. There were significant differences (P < .0001) between suture types, with 1-PDS proving best compared with 0-PDS, which was stronger than 2-0 Ethibond. Selection of suture material had the greatest impact on vertical mattress load to failure and was not important to the strength of the other techniques. 相似文献
42.
Reoperation for prosthetic heart valve replacement 总被引:1,自引:0,他引:1
M J de Bruin L K Lacquet S H Skotnicki J G Vincent J J van der Meer 《The Thoracic and cardiovascular surgeon》1986,34(1):12-16
From 1974 to 1984, 847 heart valve replacement operations were performed with 1005 prosthetic valves. Thirty-nine (4.6%) were reoperations with 43 prosthetic valve replacements (PVR), on 38 patients. Thirty-three patients had received their initial valve replacement in our hospital and 5 elsewhere. Twenty additional cardiac procedures were required, concomitantly with the prosthesis replacement. Twenty-three patients underwent replacement of a mechanical prosthesis (61%) an average of 4.3 years after initial implantation and 15 patients a bioprosthesis (39%) after 2.8 years. Indications for PVR were endocarditis in 15 patients (39%), prosthesis failure in 13 (34%), periprosthetic leak in 7 (18%), thrombosis in 2 (5%), and a left ventricle subannular aneurysm in 1 (3%). Preoperatively 4 patients were in NYHA functional class II (11%), 15 in class III (39%) and 19 in class IV (50%). Six patients died early postoperatively (15.8%) Various risk factors were analyzed. The early mortality rate was 22% for mechanical prosthesis replacement and 7% for bioprosthesis; 11% for aortic position, 13% for mitral position and 50% to 100% for double valve replacement; 23% for non-elective and 6% for elective operations; 10% for patients with only an initial valve replacement and 43% with additional previous valve operations; 18% for active endocarditis, 15% for prosthesis failure, 14% for periprosthetic leak, 0% for thrombosis and 100% for subannular aneurysm; 0% for patients in class II, 7% in class III and 26% in class IV; 6% in patients with an aortic cross-clamp time less than 2 hours and 24% with more; 27% prior to 1981 and 9% during the last 4 years; and finally 50% in patients over the age of 60.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
43.
Regional anaesthesia provides many advantages and can be practised safely in ambulatory surgery. It provides better postoperative pain control, avoids many complications associated with general anaesthesia and shortens recovery time. However, extra time required, associated complications and acceptance of patients are the factors of concern in practising regional anaesthesia in an ambulatory setting. This review will discuss various regional anaesthesia techniques suitable for outpatients. 相似文献
44.
D. Peres-Bota H. Rodriguez-Villalobos G. Dimopoulos C. Melot J.-L. Vincent 《Clinical microbiology and infection》2004,10(6):550-555
The incidence, risk factors and prognostic factors for candidal infection were determined in a prospective study of 280 infected patients. Thirty-one (11%) patients were infected with Candida spp., sub-divided into 18 (58%) with C. albicans, and 13 (42%) with non-albicans spp. (six C. glabrata, three C. parapsilosis, and one each of C. krusei, C. tropicalis, C. guilliermondii and C. lusitaniae). Infection with Candida spp. was always associated with concurrent bacterial infection. By univariate logistic regression analysis, the degree of morbidity and the duration of mechanical ventilation were independent predictive factors for death, but infection with Candida spp., was not. Factors associated with Candida spp. infection were the degree of morbidity, intensive care unit length of stay, alterations of immune response, and the number of medical devices involved. By multivariate logistic regression analysis, the only independent risk factor for candidal infection was intensive care unit length of stay. 相似文献
45.
The immune response of Drosophila melanogaster 总被引:4,自引:0,他引:4
Summary: The response of the fruit fly Drosophila melanogaster to various microorganism infections relies on a multilayered defense. The epithelia constitute a first and efficient barrier. Innate immunity is activated when microorganisms succeed in entering the body cavity of the fly. Invading microorganisms are killed by the combined action of cellular and humoral processes. They are phagocytosed by specialized blood cells, surrounded by toxic melanin, or lysed by antibacterial peptides secreted into the hemolymph by fat body cells. During the last few years, research has focused on the mechanisms of microbial recognition by various pattern recognition receptors and of the subsequent induction of antimicrobial peptide expression. The cellular arm of the Drosophila innate immune system, which was somehow neglected, now constitutes the new frontier. 相似文献
46.
Efficacy and safety of xaliproden in amyotrophic lateral sclerosis: results of two phase III trials.
Vincent Meininger Gilbert Bensimon Walter R Bradley Benjamin Brooks Patrice Douillet Andrew A Eisen Lucette Lacomblez P Nigel Leigh Wim Robberecht 《Amyotrophic lateral sclerosis and other motor neuron disorders》2004,5(2):107-117
Amyotrophic lateral sclerosis (ALS) is a relentlessly progressive and fatal motor neuron disease. We carried out two randomized, double-blind, placebo-controlled, multi-centre, multi-national studies with xaliproden (a drug with neurotrophic effect) to assess drug efficacy and safety at two doses. Patients with clinically probable or definite ALS of more than 6 months and less than 5 years duration were randomly assigned to placebo, 1 mg or 2 mg xaliproden orally once daily as monotherapy in Study 1 (n=867); or to the same regimen with addition of riluzole 50 mg bid background therapy in Study 2 (n=1210 patients). The two primary endpoints were defined as: 1. Time to death, tracheostomy, or permanent assisted ventilation (DTP), and 2. Time to vital capacity (VC)<50% or DTP before (log-rank test) and after adjustment using a Cox proportional hazard model for prespecified prognostic factors. Secondary endpoints were rates of change of various functional measures. In Study 1, primary outcome measures did not reach statistical significance. For the 2 mg group, for time to VC<50% analysis (without DTP) a significant 30% RRR was obtained (95% confidence interval [CI]: 8.46, P=0.009). In Study 2, no significant results were obtained. However, there was a trend in favour of add-on 1 mg dose xaliproden vs. placebo (RRR 15% [-6.31, ns] for time to VC<50%; RRR 12% [CI: -6.27, ns] for time to VC<50% or DTP). Adjusted RR ratios were consistently more favourable for the xaliproden groups. Tolerability was good, and dose-dependent side effects were largely associated with the serotonergic properties of xaliproden. An effect of xaliproden on functional parameters, especially VC, was noted. Although this effect did not reach statistical significance, xaliproden had a small effect on clinically noteworthy aspects of disease progression in ALS. 相似文献
47.
Vincent DeAngelis 《American journal of orthodontics and dentofacial orthopedics》2003,124(4):19A-20A, author reply 20A
48.
Ultrasound of soft tissue abnormalities of the extremities 总被引:2,自引:0,他引:2
L M Vincent 《Radiologic clinics of North America》1988,26(1):131-144
Ultrasound may be the preferred initial diagnostic modality for the painful swollen extremity, the palpable extremity mass, and the injured extremity. The role of ultrasound in extremity soft tissue abnormalities, including muscle hemorrhage and injury, inflammatory processes, and soft tissue neoplasms, is the subject of this review. 相似文献
49.
50.
Neuroleptics influence a variety of putative neurotransmitters in the basal ganglia, including somatostatin and substance P. Most studies have been performed in animals after only 3 or 4 weeks of neuroleptic administration and have seldom examined the effects of withdrawal. To understand better the effects of haloperidol on neuropeptide systems, the effects of short-term (3 weeks) and long-term (8 months) administration, as well as withdrawal from long-term administration of haloperidol, on somatostatin and substance P concentrations were examined in the rat. Short-term haloperidol significantly decreased the concentrations of somatostatin in the caudate-putamen, nucleus accumbens, and ventral tegmental area, and decreased the concentration of substance P in the substantia nigra and the nucleus accumbens. However, long-term administration only decreased the concentration of somatostatin in the nucleus accumbens. In addition, a slight reduction in the concentration of substance P in the medial prefrontal cortex was detected after long-term treatment. After withdrawal from long-term haloperidol administration the concentrations of these peptides did not differ from control values in any of the brain regions examined. These results confirm that dopamine receptor blockade can affect the somatostatin and substance P systems in the basal ganglia and indicate that during long-term administration (8 months) tolerance develops to some of the effects that are observed after shorter (3 weeks) treatment periods. 相似文献