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991.
Pelvic girdle reconstruction based on spinal fusion and ischial screw fixation in a case of aneurysmal bone cyst
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A case of lytic lesion of the pelvis in a 23-year-old woman is presented. A biopsy led to the diagnosis aneurysmal bone cyst (ABC). Due to the histologically very aggressive growth of the tumor, a low malignant osteosarcoma could not be excluded. In an initial operation the tumour, affecting the sacrum, the iliac crest and the lower lumbar spine was resected. Temporary restabilisation of the pelvic ring was achieved by a titanium plate. The histological examination of the entire tumour confirmed the diagnosis ABC. After 6 months, the MRI showed no recurrence. The observed tilt of the spine to the operated side on the sacral base prompted a second surgical procedure: a transpedicular fixation of L5 and L4 was connected via bent titanium stems to the ischium, where the fixation was achieved by two screws. This construction allowed the correction of the base angle and yielded a stable closure of the pelvic ring. The patient has now been followed for 6 years: the bone grafts have been incorporated and, in spite of radiological signs of screw loosening in the ischium, the patient is fully rehabilitated and free of symptoms. Pedicle screws in the lower spine can be recommended for fixation of a pelvic ring discontinuity. 相似文献
992.
A meta-analysis on the efficacy of preoperative biliary drainage for tumors causing obstructive jaundice 总被引:25,自引:0,他引:25
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OBJECTIVE: To review the effectiveness of preoperative biliary drainage (PBD) in patients with obstructive jaundice resulting from tumors. SUMMARY BACKGROUND DATA: This was a systematic review, including a meta-analysis, of randomized controlled trials and comparative cohort studies conducted worldwide and published between 1966 and September 2001, classified on methodologic strength and subdivided into level 1 (randomized controlled trials) and level 2 (comparative cohort studies). METHODS: Comparison was made of PBD versus no PBD in jaundiced patients undergoing resection of a tumor. Outcome measures were in-hospital death rate, overall complications resulting from the treatment modality (drainage- and surgery-related complications), and hospital stay. Effect sizes were calculated and combined in meta-analyses. Relative differences (%) were calculated to compare effects on outcome measures. RESULTS: Five randomized controlled studies comprising 302 patients met the inclusion criteria for level 1 studies, and 18 cohort studies comprising 2,853 patients met the criteria for level 2 studies. Meta-analysis of level 1 studies showed no difference in the overall death rate between patients who had PBD and those who had surgery without PBD. The overall complication rate, however, was significantly adversely affected by PBD compared with surgery without PBD. At level 2, there was no difference in the death rate between the two treatment modalities. The overall complication rate, however, was significantly adversely affected by PBD compared with surgery without PBD. If PBD had been without complications, then complications would be in favor of drainage based on level 1 studies, and no difference based on level 2 studies. Further, PBD was not able to reduce the length of postoperative hospital stay compared with surgery without PBD; instead, it prolonged the stay. CONCLUSIONS: This meta-analysis shows that PBD with current standards for patients with obstructive jaundice resulting from tumors carries no benefit and should not be performed routinely. The potential benefit of PBD in terms of postoperative rates of death and complications does not outweigh the disadvantage of the drainage procedure. Only if PBD-related complications could be reduced by 27% and consequently diminish hospital stay could PBD be beneficial. Further randomized controlled trials with improved PBD techniques are necessary. 相似文献
993.
The impact of impaired insulin release and insulin resistance on glucose intolerance after renal transplantation 总被引:2,自引:0,他引:2
Hjelmesaeth J Hagen M Hartmann A Midtvedt K Egeland T Jenssen T 《Clinical transplantation》2002,16(6):389-396
The current knowledge of the pathogenesis of post-transplant glucose intolerance is sparse. This study was undertaken to assess the relative importance of insulin secretion (ISec) and insulin sensitivity (IS) in the pathogenesis of post-transplant diabetes mellitus (PTDM), impaired glucose tolerance (IGT) and impaired fasting glucose (IFG) after renal transplantation. An oral glucose tolerance test (OGTT) was performed in 167 non-diabetic recipients 10 wk after renal transplantation. Fasting, 1-h and 2-h insulin and glucose levels were used to estimate the insulin secretory response and IS. One year after transplantation 89 patients were re-examined with an OGTT including measurements of fasting and 2 h glucose. Ten weeks after transplantation the PTDM-patients had significantly lower ISec and IS than patients with IGT/IFG, who again had lower ISec and IS than those with normal glucose tolerance (NGT). One year later, a similar difference in baseline ISec was observed between the three groups, whereas baseline IS did not differ significantly. Patients who improved their glucose tolerance during the first year, were mainly characterized by a significantly greater baseline ISec, and they received a significantly higher median prednisolone dose at baseline with a subsequent larger dose reduction during the first year, than the patients who had their glucose tolerance unchanged or worsened. In conclusion, both impaired ISec and IS characterize patients with PTDM and IGT/IFG in the early course after renal transplantation. The presence of defects in insulin release, rather than insulin action, indicates a poor prognosis regarding later normalization of glucose tolerance. 相似文献
994.
995.
Blindt R Bosserhoff AK vom Dahl J Hanrath P Schrör K Hohlfeld T Meyer-Kirchrath J 《European journal of pharmacology》2002,444(1-2):31-37
Migration of vascular smooth cells from the media to the intima essentially contributes to neointima formation after percutaneous transluminal angioplasty and stent implantation. The stable prostacyclin mimetic iloprost has been shown to inhibit neointima formation in experimental restenosis, but it is currently unknown whether this may be caused by an antimigratory effect. Hence, the present study analyses (i) the influence of G(s)-coupled prostacyclin (IP) receptors on cell migration and (ii) verifies whether EP(3) receptors with opposite (i.e., G(i)) coupling may conversely stimulate cell migration. In a modified Boyden chamber model, it was shown that iloprost dose-dependently inhibits the migration of primary human arterial smooth muscle cells, which constitutively express the IP receptor. On the other hand, human arterial smooth muscle cell migration was stimulated by the EP(3) receptor agonist M&B 28.767. To independently study the effects of these receptors, IP or EP(3) receptors were stably overexpressed in chinese hamster ovary cells (CHO-IP and CHO-EP(3)). Chemotaxis of CHO cells transfected with G(s)-coupled IP receptors was concentration-dependently inhibited by iloprost (2-100 nM), while there was no effect of iloprost on mock-transfected CHO. By contrast, CHO-cells that overexpressed EP(3) receptors showed a significant, concentration dependent (1-100 nM) increase of cell migration in presence of the selective EP(3) agonist M&B 28.767. It is concluded that the prostacyclin mimetic iloprost inhibits vascular cell migration, which probably depends on a G(s)-mediated increase of intracellular cAMP. EP(3) receptors conversely stimulate CHO migration. 相似文献
996.
Purpose. To measure changes in pH as well as osmotic pressure in aqueous pores and cavities inside biodegradable microspheres made from polymers such as poly(D,L-lactic acid) (PLA) and poly(D,L-lactic acid -co- glycolic acid) (PLGA).
Methods. The internal osmotic pressure inside eroding PLA microspheres was analyzed with differential scanning calorimetry (DSC) in a temperature range of 10 to –25°C. The osmotic pressure was calculated from the melting peaks of the aqueous phase using purity analysis. For pH determination, PLGA microspheres were loaded with a pH-sensitive spin probe which allowed the determination of pH by electron paramagnetic resonance (EPR).
Results. The osmotic pressure in PLA microspheres increased to 600 mOsm within four days and decreased to 400 mOsm after two weeks. The pH in PLGA microspheres in this study was 4.7. Basic drugs such as gentamicin free base or buffering additives led to a pH increase. In no case, however, did the internal pH exceed a value of 6 within 13 hours.
Conclusions. DSC and EPR are useful techniques to characterize the chemical microenvironment inside eroding microspheres. This data in combination with detailed information on peptide and protein stability could allow in the future to predict the stability of such compounds within degradable polymers. 相似文献
997.
The ciliary epithelia of human fetal and adult eyes were investigated for the presence of intermediate filament proteins. Coexpression of cytokeratin and vimentin was found. This resembles the intermediate filament pattern of choroid plexus epithelium, another neuroepithelial tissue with secretory function. 相似文献
998.
Di Marco R Mangano K Quattrocchi C Musumeci R Speciale AM Papaccio G Buschard K Bendtzen K Nicoletti F 《Clinical immunology (Orlando, Fla.)》2003,109(3):266-271
Fusidic acid and sodium fusidate (fusidin) are antibiotics with low toxicity and powerful immunomodulatory activities in vitro and in vivo. In this study we have evaluated the effect of fusidin on the development of dinitrobenzenesulfonic acid (DNB)-induced colitis in rats that serves as a preclinical model of human inflammatory bowel disease (IBD). The data show that when administered orally at the dose of 80 (but not 40) mg/kg body wt under a "therapeutic" regimen soon after DNB application, fusidin significantly ameliorates clinical, histological, and seroimmunological signs of disease. These entailed a significant reduction in body weight loss, smaller increase in colon weights, milder macroscopic damage, and lower histological scores. In addition, when sacrificed at the end of the study, fusidin-treated rats had significantly lower blood levels of tumor necrosis factor alpha and interferon-gamma compared with untreated controls. The present findings concur with the beneficial actions of fusidin in a pilot study conducted in patients with Crohn's disease and warrant controlled studies in humans with IBD. 相似文献
999.
Henrik S. Hansen Karsten Froberg Jens Rokkedal Nielsen Niels Hyldebrandt 《European journal of applied physiology》1989,58(6):618-624
Summary In two experiments maximal aerobic power
calculated from maximal mechanical power (W
max) was evaluated in 39 children aged 9–11 years. A maximal multi-stage cycle ergometer exercise test was used with an increase in work load every 3 min. In the first experiment oxygen consumption was measured in 18 children during each of the prescribed work loads and a correction factor was calculated to estimate
using the equation
. An appropriate increase in work rate based on height was determined for boys (0.16 W · cm–1) and girls (0.15 W · cm–1) respectively. In the second experiment 21 children performed a maximal cycle ergometer exercise test twice. In addition to the procedure in the first experiment a similar exercise test was performed, but without measurement of oxygen uptake. Calculated
correlated significantly (p<0.01) with those values measured in both boys (r=0.90) and girls (r=0.95) respectively, and the standard error of estimation for
(calculated) on
(measured) wass less than 3.2%. Two expressions of relative work load (%
and %W
max) were established and found to be closely correlated. The relative work load in %
could be predicted from the relative work load in % W
max with an average standard error of 3.8%. The data demonstrate that calculated
based on a maximal multi-stage exercise test provides an accurate and valid estimate of
相似文献
1000.
Although the presence of mast cells in heart muscle is well documented, their possible presence in heart cell cultures has not yet been considered. In this paper we show for the first time that cultures from neonatal rat hearts contain mast cells in proportions which may exert physiological influences on heart muscle cells. Evidence is based on cytochemistry, immunocytochemistry with a monoclonal antibody (F2) specific for connective tissue mast cells of the rat, and direct estimations of both cellular histamine and histamine released into the culture medium. Since the number of nonmuscle cells immunoreactive with antibody F2 exceeded the number of cells reacting with conventional cytochemical stains for mast cells, a substantial proportion of the former may represent less differentiated (precursor) cells. 相似文献