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131.
PURPOSE: Starting from a status hypercoagulability previous to substitutive hip and knee surgery, the aim of this work was to investigate the influence of different osteoarthropatic pictures for which arthroplasty is indicated in the activation of the clotting cascade, rheumatoid arthritis (RA) being one of such pictures. PATIENTS AND METHODS: Of 79 patients suitable for prosthetic surgery of hip (53) and knee (26), the preoperative values of several markers, namely, D dimers (D-D), thrombin-antithrombin (TAT) complex, and F1 + 2 prothrombin fragment (F1 + F2) were assessed by enzymoimmunoasay. The mean age of the patients was 65.5 years, and their sex distribution was 50 women and 29 men. The indications for arthroplasty were as follows: osteoarthrosis (62), aseptic necrosis (11), RA (9), articular gout (2), previous fracture (2), more than one diagnosis overlapped in some cases. The results attained were compared with a control group comprised of 33 subjects (16 women and 17 men) with mean age similar to the patient's group (68.06 years). RESULTS: The D-D values in the patients suitable for hip arthroplasty and the TAT values in patients suitable for both types of surgery were significantly higher than those found in the control group (p = 0.012 and 0.01, respectively). The preoperative TAT levels of the RA patients were significantly higher (p = 0.025) than those found in the patients with the other surgical indications. CONCLUSIONS: Previously to the performance of arthroplasty, the patients show hypercoagulative marker values higher than those of age-matched controls. The significant rising of TAT found in RA patients is concordant with the literature, and this fact makes it advisable to include RA among the pathologic situations associated with hypercoagulability, as this is a common indication for substitutive hip and knee surgery with high risk of venous thromboembolic disease. 相似文献
132.
AIM: To determine whether antenatal administration of thyrotrophin releasing hormone (TRH), to promote lung maturation, alters blood flow through the fetal middle cerebral, umbilical artery, or ductus arteriosus and through the maternal uterine arteries. METHODS: The effect of transplacentally administered TRH on the fetal circulation was prospectively evaluated in 30 patients between 24 and 34 weeks' gestation. TRH (400 micrograms) was given to the mother intravenously either as a bolus or an infusion. Fetal effects were determined by measuring the maximum velocity and pulsatility index (PI) in middle cerebral artery, ductus arteriosus, uterine artery and umbilical artery Doppler waveforms. Measurements were made immediately before, and 10 and 60 minutes after maternal TRH administration. RESULTS: Intravenous injection of TRH had no significant effect on PI in the uterine, umbilical, or middle cerebral artery and the ductus arteriosus within 60 minutes of administration in either group. CONCLUSION: The antenatal use of TRH in conjunction with steroids for fetal lung maturity does not affect utero-placental or fetal haemodynamic variables, as measured by Doppler. These findings, therefore, do not support the suggestion that antenatal intravenous administration of TRH either as bolus or infusion may have immediate adverse vascular effects in the fetus. 相似文献
133.
Using Western-blot analysis, we identified eight immunodominant antigens (apparent molecular weights 96, 86, 75, 56, 41, 32, 28, and 26 kDa) of Strongyloides stercoralis in natural human infections. For this study, 78 individual serum samples were obtained from S. stercoralis-infected patients residing in endemic areas of the United States. Poly A+ RNA was translated in vitro in the rabbit-reticulocyte lysate system. The newly synthesized translation products were immuno-precipitated with S. stercoralis human infection sera. All eight of the identified antigens were detected in the immunoprecipitates. The potential of these antigens as targets for immunodiagnosis is also discussed. 相似文献
134.
T Barkas SF AL-Khateeb WJ Irvine NM Davidson P Roscoe 《Canadian Metallurgical Quarterly》1976,25(2):270-279
Circulating immune complexes in the sera of patients with thyroid disorders or bronchogenic carcinoma were investigated using an assay system based on the inhibition of the ADCC activity of rat spleen cells. Increased inhibition, as compared with that of the sera of age and sex matched controls, was found in patients with thashimoto thyroiditis, primary hypothyroidism and bronchogenic carcinoma. The degree of inhibition in the first two groups was markedly increased compared with control sera of the same IgG content. However, the results in the lung cancer group were slightly but not significantly greater than in controls with the same level of IgG. Increased IgG levels were found in patients with thashimoto thyroiditis and thyrotoxicosis, and also in patients with bronchogenic carcinoma who had mediastinal gland involvement. The lower level of sensitivity of the assay system was approximately 600 ng added aggregated IgG, corresponding to a concentration of 6mu g/ml in the sample assayed. It is possible that circulating immune complexes may exist in lung cancer, but at a level below that of the present assay system. 相似文献
135.
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137.
Synthetic human beta-endorphin increased plasma glucose concentration when administered intracisternally in chronically cannulated, conscious, unrestrained, adult male rats. This hyperglycemic effect of beta-endorphin was blocked by prior systemic administration of naloxone, supporting mediation of the effect at opioid receptors in brain. Adrenal denervation blocked the beta-endorphin-induced increase in plasma glucose, supporting a thesis that this effect is mediated at least in part by increased epinephrine secretion. The hyperglycemic response to intracerebral beta-endorphin was also blocked by either intracerebral hemicholinium-3 or somatostatin, supporting both a cholinergic link and a somatostatin neuron in the brain mechanism regulating endorphin-induced stimulation of sympathetic outflow. 相似文献
138.
AC Galloway SB Colvin EA Grossi MA Parish AT Culliford T Asai NM Rofsky JC Weinreb S Shapiro FG Baumann 《Canadian Metallurgical Quarterly》1993,105(5):781-8; discussion 788-90
During an 8-year period (1984 to 1991) 66 patients (mean age 59 years, range 26 to 84 years) with type A aortic dissection (60 ascending aorta tears, 6 arch tears; 35 acute, 31 chronic) had surgical repair by a continuous suture-graft inclusion technique. Hypothermic circulatory arrest (16 degrees C) was used in 58 patients (35/35 acute, 23/31 chronic; mean arrest time 26 minutes, range 10 to 55 minutes). Fifty-two patients had hemiarch repair and 6 had total arch replacement. Aortic valve disease necessitated treatment in 38 patients (1 valved conduit, 20 valve replacements, 17 valve repairs). Recently 11 patients had valve repair by reconstruction of the native aortic root, by means of techniques similar to those used for homograft valve insertion. Operative mortality was 9% (14% acute, 3% chronic). Stroke occurred in 2 patients (3%) and was fatal in both. Variables suggestive of increased operative risk by univariate analysis were acuteness (p = 0.12), visceral ischemia (p = 0.12), and preoperative shock (p = 0.13). No variable was significant by multivariate analysis. Overall actuarial survival at 48 months was 77%, with 3 late deaths from a ruptured distal aneurysm. Late computed tomography or magnetic resonance imaging scan was done in 28 patients at a mean interval of 33 months. These studies identified 1 patient with a pseudoaneurysm requiring reoperation and 3 patients with contained flow between the graft and the wrap. Three patients required late operation: 1 for pseudoaneurysm, 1 for arch dissection, and 1 for repair of a distal aneurysm. 相似文献
139.
Protective effects of an aptamer inhibitor of neutrophil elastase in lung inflammatory injury 总被引:1,自引:0,他引:1
NM Bless D Smith J Charlton BJ Czermak H Schmal HP Friedl PA Ward 《Canadian Metallurgical Quarterly》1997,7(11):877-880
Neutrophils play an important part in the development of acute inflammatory injury. Human neutrophils contain high levels of the serine protease elastase, which is stored in azurophilic granules and is secreted in response to inflammatory stimuli. Elastase is capable of degrading many components of extracellular matrix [1-4] and has cytotoxic effects on endothelial cells [5-7] and airway epithelial cells. Three types of endogenous protease inhibitors control the activity of neutrophil elastase, including alpha-1 protease inhibitor (alpha-1PI), alpha-2 macroglobulin and secreted leukoproteinase inhibitor (SLPI) [8-10]. A disturbed balance between neutrophil elastase and these inhibitors has been found in various acute clinical conditions (such as adult respiratory syndrome and ischemia-reperfusion injury) and in chronic diseases. We investigated the effect of NX21909, a selected oligonucleotide (aptamer) inhibitor of elastase, in an animal model of acute lung inflammatory disease [11-14]. This inhibitor was previously selected from a hybrid library of randomized DNA and a small-molecule irreversible inhibitor of elastase (a valine diphenyl ester phosphonate, Fig. 1), by the blended SELEX process [15]. We show that NX21909 inhibits lung injury and neutrophil influx in a dose-dependent manner, the first demonstration of efficacy by an aptamer in an animal disease model. 相似文献
140.