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111.
Enhanced oxidative stress is a feature of inflammatory and infectious conditions. Proteins may be important targets of oxidation and this may alter their function. We evaluated whether metal-catalyzed oxidation of IgG could alter its ability to bind to Fc receptors on macrophages. Human IgG incubated with an FeCl3/EDTA/ascorbate metal-catalyzed oxidation system resulted in a significant increase in carbonyl content, a measure of protein oxidation, compared to IgG treated with EDTA alone (control). Western blot analysis using an antibody to oxidized protein revealed an increase in antibody binding to both the heavy (Fc portion-containing) and light chains of IgG treated with the oxidizing system. Western blot analysis of papain-digested IgG confirmed oxidative modification of the Fc portion. Binding studies carried out with J774.16 macrophages demonstrated significantly diminished ability of the oxidized IgG to bind to macrophage Fc receptors compared to control IgG. These data demonstrate that IgG is susceptible to metal-catalyzed oxidation and that this impairs its ability to bind to macrophage Fc receptors. Oxidation of IgG might play a role in modulating immune function in infection and disorders associated with immune complex formation by diminishing IgG binding to phagocytic cells.  相似文献   
112.
Hemodynamic parameters and survival were studied in 48 patients with noncoronarogenic myocardial diseases (NCMD). The examination included high-resolution electrocardiography and Holter monitoring of cardiac rhythm. Deterioration of pump capacity of the heart was associated with high-grade arrhythmias (4B and higher) while ventricular late potentials were more characteristic for patients with severe hemodynamic disorders and, in particular, with dilated cardiomyopathy. The prognosis in NCMD is based on clinical evidence on functional class of the heart failure, parameters of central and intrapulmonary hemodynamics.  相似文献   
113.
As revealed the velocities of urea decomposition in the citrate donor plasma with soluble urease and urease immobilized by addition to carboxymethyl ester of cellulose, 2-(3'-amino-4'-methoxyphenyl)-sulphonylethyl ester of cellulose, diethylaminoester of cellulose, stained with dichlortriazine stain, or graft copolymere of cellulose and polyglycidylmetacrylate were sufficiently close to one another. Preparations of immobilized urease can be repeatedly used for urea decomposition in the citrate donor blood. Periodical treatment of the mentioned preparations with cystein solution led to a lesser decrease of enzymatic activity of the immobilized urease after repeated use.  相似文献   
114.
The effect of short-term treatment with the highly selective serotonin receptor antagonist ondansetron on symptoms and gastric emptying in 11 carcinoid patients was studied. Diarrhoea improved in 6 of 6 patients, nausea in 3 of 4 patients. Flushing was not affected. The rate of gastric emptying increased during ondansetron treatment (P = 0.08). No changes in serotonin in platelets and urinary excretion of 5-hydroxyindoleacetic acid were found. It is concluded that ondansetron can improve gastrointestinal symptoms in carcinoid patients and possibly slows gastric emptying.  相似文献   
115.
116.
In a study to examine the methods of assessing the response of patients with chronic airways obstruction to corticosteroids, 20 patients received a week of placebo tablets, followed by three weeks of prednisolone 30 mg daily. Subjective benefit was assessed by a visual analogue scale (VAS), and objective changes by spirometry and an exercise test. Significant increases in FEV1 and in exercise performance were observed after steroid therapy. Changes in FVC correlated both with VAS score and with changes in exercise performance. Changes in FEV1 correlated with neither. The good correlation between the changes in a ventilatory function test (the FVC) and the patients' assessments of the drug suggests that the non-specific euphoriant effect of steroids does not eclipse their specific action on ventilatory function. Assessment of benefit should include a subjective assessment and changes in FVC and exercise performance. Changes in FEV1 appear to have less clinical relevance.  相似文献   
117.
The findings on roentgenographic and tomographic examination of the chest were compared in 63 instances of suspected pulmonary metastases. These were further compared with the findings at thoracotomy in 41 instances. Of the 60 patients, 30 had soft tissue or bone sarcomas and 30 had carcinomas arising from colon, ovary or breast, and it also included five with malignant melanoma. Three patients with sarcomas had more than one thoracotomy. The diagnosis of pulmonary metastases by roentgenography of the chest was correct in 60 of 63 instances. Tomograms showed more lesions in 14 of 33 instances of sarcomas and 14 of 30 instances of carcinomas. Thoracotomy revealed even more lesions than were detected by tomography in 21 out of 26 instances with sarcomas and eight of 15 instances of carcinomas. Of the 37 patients with a solitary metastasis detected on roentgenograms of the chest, 22 were found to have additional lesions on the tomograms, 11 of 16 sarcomas and 11 of 21 carcinomas. At thoracotomy, however, nine of ten patients with a single metastasis from sarcomas were found to have even more lesions, while, in patients with carcinomas, tomograms were found to be accurate. Routinely, prior to major ablative operations for sarcomas and before excision of pulmonary metastases, it is suggested that tomography be carried out.  相似文献   
118.
Follow-up (5.5 years) of monkeys with a history of acute enterovirus uveitis (AEU) after intraocular infection with ophthalmotropic ECHO 11 and ECHO 19 strains showed progressive changes in the infected eye; destruction of the iris, formation of films in the anterior chamber of the eye, deformation of the pupil, and signs of cataract and glaucoma. A short (1-30 days) stage of active reproduction of infective virus (up to 10(10) TCD50/g tissue in the first days postinfection) was followed by the second very long stage of limited specific multiplication of virus in ocular tissues. The virus was not detected during the second stage, but its components (virusspecific antigen and crystalloid accumulations of virions) were found in ophthalmic and conjunctival tissues; moreover, high levels of neutralizing antibodies were detected in the blood. The results indicate AEU transformed into a stubborn persistent infection of the eye in monkeys. The findings of this follow-up and published reports about many-year follow-up of children with AEU permit us to classify a post-uveitis disease as a special nosological form of a persistent enterovirus infection and denote it as enterovirus post-uveitis syndrome. The main signs of this syndrome are a history of AEU, progressive destructive changes in the anterior segment of the eye, presence of virus components in ocular tissues in remote periods after infection, and high antibody level in the blood.  相似文献   
119.
Rifampicin is rapidly absorbed when administered orally. Its high levels were detected during 1 to 3 hours after administration. The antibiotic was preserved in the blood serum in therapeutic concentrations for at least 24 hours depending on the dose used. When used repeatedly, it did not cumulate. Rifampicin easily penetrated into the organs and tissues of the animals, the highest concentrations being observed in the liver and kidneys. The antibiotic was mainly excreted with the bile. The drug pharmacokinetics depended on the animal species.  相似文献   
120.
It was established that in the acute period of the ischemic stroke in the maiority of cases a change of isoenzyme structure of LDG thrombocytes was due to a decrease of LDG3 activity. In a number of patients the dominant change in the spectrum was determined by LDG and LDG4 fractions. The changes were of a stable character up to 10 weeks. LDG4 increase was characteristic of the isoenzymes spectrum in the patients with a severe development of the disease and in the patients in the remote period of the stroke. The obtained data can serve as a criterion for evaluating the adaptive changes in acute brain ischemia.  相似文献   
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