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1.
Justine Royle Rachel Williamson Mark Strachan Marie O’Donnell Simon Jackson Thanos Argryopoulos Alan McNeill 《British journal of medical & surgical urology》2009,2(5):204-207
Emphysematous pyelonephritis is a severe life-threatening infection which continues to carry significant morbidity and mortality. We present a case recently managed at our institution by laparoscopic nephrectomy. The patient survived, and in comparison to some of the more conventionally managed patients in the literature, made an extremely speedy recovery. We would advocate this option to be seriously considered when patients are suitable and appropriately trained surgeons are available. 相似文献
2.
Stewart Shapiro Dimitris N. Tatakis Dr. Rosemary Dziak 《Calcified tissue international》1990,46(1):60-62
Summary Tumor necrosis factor α (10−10–10−8M) had no effects on cyclic AMP production by the osteoblastic osteosarcomal cells, Saos-2 and G292, or normal rat calvarial
cells. The cytokine did, however, inhibit the parathyroid hormone (PTH)-induced effect on cyclic AMP in the Saos-2 and normal
rat osteoblastic cells. This inhibitory effect did not occur on prostaglandin E2-induced cyclic AMP increases in the osteoblastic cells. Interleukin-1 (10 U/ml −100 U/ml) did not produce any effect on basal
levels or PTH-induced cyclic AMP increases in these cells. 相似文献
3.
A binocular machine vision system for three-dimensional surface measurement of small objects 总被引:1,自引:0,他引:1
Rendering three-dimensional information of a scene from optical measurements is very important for a wide variety of applications. However, computer vision advancements have not yet achieved the accurate three-dimensional reconstruction of objects smaller than 1 cm diameter. This paper describes the development of a novel volumetric method for small objects, using a binocular machine vision system. The achieved precision is high, providing a standard deviation of 0.04 mm. The robustness, of the system, issues from the lab prototype imaging system with the crucial z-axis movement without the need of further calibration and the fully automated volumetric algorithms. 相似文献
4.
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
5.
Rachel M Massey Oliver J Warren Michal Szczeklik Sophie Wallace Daniel R Leff John Kokotsakis Ara Darzi Thanos Athanasiou 《Journal of cardiothoracic surgery》2007,2(1):26-9
The use of a skeletonized internal thoracic artery in coronary artery bypass graft surgery has been shown to confer certain
advantages over a traditional pedicled technique, particularly in certain patient groups. Recent reports indicate that radial
and gastroepiploic arteries can also be harvested using a skeletonized technique. The aim of this study is to systematically
review the available evidence regarding the use of skeletonized radial and gastroepiploic arteries within coronary artery
bypass surgery, focusing specifically on it's effect on conduit length and flow, levels of endothelial damage, graft patency
and clinical outcome. Four electronic databases were systematically searched for studies reporting the utilisation of the
skeletonization technique within coronary revascularisation surgery in humans. Reference lists of all identified studies were
checked for any missing publications. There appears to be some evidence that skeletonization may improve angiographic patency,
when compared with pedicled vessels in the short to mid-term. We have found no suggestion of increased complication rates
or increased operating time. Skeletonization may increase the length of the conduit, and the number of sequential graft sites,
but no clear clinical benefits are apparent. Our study suggests that there is not enough high quality or consistent evidence
to currently advocate the application of this technique to radial or gastroepiploic conduits ahead of a traditional pedicled
technique. 相似文献
6.
Thomas Modine Christophe Decoene Sharif Al-Ruzzeh Thanos Athanasiou Pierre Poivre Annie Pol Georges Fayad 《European journal of cardio-thoracic surgery》2005,27(2):289-295
OBJECTIVE: Dobutamine is commonly used to improve ventricular performance in cardiac surgery. The aim of this prospective randomised controlled study was to assess the effectiveness of using low doses of dobutamine during off-pump coronary artery bypass (OPCAB) surgery in order to reduce haemodynamic compromise due to heart displacement. METHODS: Thirty-two patients undergoing elective coronary artery bypass grafting (CABG) surgery using OPCAB technique for more than two vessels were approached and recruited. We analysed the changes in the thoracic aortic blood flow (TABF) during OPCAB using transoesophageal Doppler and by other conventional monitoring methods as cardiac output, invasive pulmonary and radial pressures and mixed venous oxygen saturation. RESULTS: The two groups were similar in preoperative characteristics. No postoperative complications were observed in the study patients. The heart rate, right atrial pressure, cardiac output measured by thermodilution and TABF changed significantly during the procedure. Also significant changes in descending thoracic aortic diameter were observed. The postoperative creatinine was significantly lower in the dobutamine group (P=0.04). Dobutamine was found responsible for the improvement in the descending TABF (P=0.006). CONCLUSIONS: This study showed that intra-operative intravenous infusion of dobutamine at 5 microg/kg per min in routine OPCAB patients safely increased cardiac output even without such changes been detected by conventional monitoring methods. 相似文献
7.
Clio Mamalaki Marianna Murdjeva Mauro Tolaini Trisha Norton Phillip Chandler Alain Townsend Elizabeth Simpson Dimitris Kioussis 《Clinical & developmental immunology》1995,4(4):299-315
Influenza nucleoprotein (NP)-specific T-cell receptor transgenic mice (F5) were crossed
with transgenic mice expressing the cognate antigenic protein under the control of the H-
2Kb promoter. Double-transgenic mice show negative selection of thymocytes at the
CD4+8+TCR10 to CD4+8+TCRhi transition stage. A few CD8 T cells, however, escape clonal
deletion, and in the peripheral lymphoid organs of these mice, they exhibit low levels of
the transgenic receptor and upregulated levels of the CD44 memory marker. Such cells do
not proliferate upon exposure to antigen stimulation in vivo or ex vivo, however, they can
develop low but detectable levels of antigen-specific cytotoxic function after stimulation
in vitro in the presence of IL-2. 相似文献
8.
Susanne Krmer Clio Mamalaki Ivan Horak Anneliese Schimpl Dimitris Kioussis Thomas Hünig 《European journal of immunology》1994,24(10):2317-2322
The requirement for interleukin-2 (IL-2) in repertoire selection and peripheral activation of CD8 T cells was tested in mice rendered IL-2 deficient by gene targeting and expressing a transgenic T cell receptor (TcR) (F5) specific for influenza nucleoprotein (NP) 366-374 + H-2Db. Positive selection of the transgenic F5 TcR into the CD8 compartment proceeded normally. Both in vivo and in vitro, the antigenic peptide induced depletion of immature thymocytes and proliferation of mature CD8 T cells regardless of the presence of an intact IL-2 gene. In contrast, cytotoxic T lymphocyte (CTL) activity was only generated by T cells from IL-2+ F5 transgenic mice. Exogenous IL-2 was able to fully restore the CTL response of IL-2?/? responder cells in vitro. Thus, both in vivo and in vitro, clonal expansion of CD8 T cells can proceed in the absence of IL-2, whereas in peptide-immunized F5 transgenic mice, induction of cytotoxic effector function is IL-2 dependent. 相似文献
9.
Papadimitriou GN Dikeos DG Souery D Del-Favero J Massat I Avramopoulos D Blairy S Cichon S Ivezic S Kaneva R Karadima G Lilli R Milanova V Nöthen M Oruc L Rietschel M Serretti A Van Broeckhoven C Stefanis CN Mendlewicz J 《Psychiatric genetics》2003,13(4):211-220
The co-segregation in one pedigree of bipolar affective disorder with Darier's disease whose gene is on chromosome 12q23-q24.1, and findings from linkage and association studies with the neighbouring gene of phospholipase A2 (PLA2) indicate that PLA2 may be considered as a candidate gene for affective disorders. All relevant genetic association studies, however, were conducted on bipolar patients. In the present study, the possible association between the PLA2 gene and unipolar affective disorder was examined on 321 unipolar patients and 604 controls (all personally interviewed), recruited from six countries (Belgium, Bulgaria, Croatia, Germany, Greece, and Italy) participating in the European Collaborative Project on Affective Disorders. After controlling for population group and gender, one of the eight alleles of the investigated marker (allele 7) was found to be more frequent among unipolar patients with more than three major depressive episodes than among controls (P<0.01); genotypic association was also observed, under the dominant model of genetic transmission (P<0.02). In addition, presence of allele 7 was correlated with a higher frequency of depressive episodes (P<0.02). These findings suggest that structural variations at the PLA2 gene or the chromosomal region around it may confer susceptibility for unipolar affective disorder. 相似文献
10.
Smyth LA Ardouin L Williams O Norton T Tybulewicz V Kioussis D 《European journal of immunology》2002,32(12):3386-3394
Interactions of T cells with MHC plus peptide in the peripheral lymphoid system are important for their survival. In this study we investigated further the molecular consequences of such interactions using F5 TCR transgenic mice and peptides previously shown to induce either negative or positive selection in the thymus. Following TCR ligation with the negatively selecting agonist peptide, mature CD8(+) cells proliferated and up-regulated the activation marker CD69. Interestingly, ligation of this TCR with MHC molecules loaded with high concentrations of the positively selecting peptide also resulted in the aforementioned changes, but with slower kinetics. Analysis of the biochemical changes that occur following stimulation with these peptides showed that phosphorylation of key signaling molecules, such as ZAP-70, CD3zeta, Vav, SLP-76, LAT, and ERK-1 and 2, could be detected after exposure to agonist but not antagonist peptide. Confocal microscopy, however, revealed infrequent phosphorylation 'patches' at the site of contact between T cells and APC presenting the antagonist peptide. Our data suggest that peptides capable of inducing positive selection in the thymus can be recognized by mature T cells and cause proliferation, up-regulation of CD69 and accumulation of phosphorylated proteins at the immunological synapse with low efficiency; however no phosphorylation of signaling molecules can be detected using conventional biochemical assays. 相似文献