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991.
The effects of physical training on elderly, fragile patients with rheumatoid arthritis (RA) who are on low-dose steroids were investigated. The controlled study included 24 patients who had been treated with low-dose steroids for 2 years. Each patient was assigned either to a treatment group receiving training or to an untrained control group. The training took place over a 3-month period and was based on a protocol using progressive interval training consisting of bicycle exercises, heel lifts, and step-climbing. The exercises were performed twice weekly for 45 minutes. Comparison of the two groups showed that disease activity did not increase in the trained group and that fewer, but not significantly fewer, swollen joints were observed in this group (p = 0.06). No significant changes were noticed in erythrocyte sedimentation rate, tender joints, or morning stiffness. The work capacity of the trained patients were doubled and the numbers of repetitions increased 76%. Individually adapted exercise programs can therefore be recommended for elderly rheumatoid arthritis patients on steroid treatment.  相似文献   
992.
Recent studies have shown that cyclosporin A (CsA) may affect ricin A-chain immunotoxin (RTA-IT) therapy. In this study, we evaluated the ability of CsA and its nonimmunosuppressive analog, SDZ PSC 833, to enhance anti-CD5 T101 RTA-ITs in vitro. Both 4 mumol/L CsA and 4 mumol/L SDZ PSC 833 significantly and specifically enhanced the cytotoxic activity of T101 RTA-IT on the human lymphoblastic T-cell line, CEM III (101-fold and 105-fold, respectively). Furthermore, these Cs also enhanced the cytotoxicity of the more potent T101 F(ab')2 RTA-IT (ninefold and eightfold, respectively). The effect of human plasma, originating from four patients enrolled in a phase I high-dose CsA regimen, was examined on T101 RTA-IT cytotoxicity on CEM III cells. In each case, with plasma CsA levels between 3,090 and 4,860 ng/mL (2.5 to 4 mumol/L), a significant increase in T101 RTA-IT-mediated cytotoxicity was observed ranging from 31% to 60%. Neither CsA nor SDZ PSC 833 affected the rate of RTA-IT binding, internalization, intracellular trafficking, or degradation. Analysis of internalized T101 RTA-IT molecules showed that these were essentially intact, which suggests that these enhancers may act only on a small population of RTA-ITs that escapes present investigational techniques. In conclusion, because the concentrations used are clinically achievable, Cs appear to be promising agents for in vivo enhancement of RTA-ITs.  相似文献   
993.
We have investigated the role of cellular p21ras protein in insulin and insulin-like growth factor-I (IGF-I) signaling pathways. Insulin stimulation increased Ras-GTP formation in Rat-1 fibroblasts overexpressing normal human insulin receptors (HIRc-B), far greater than in parental Rat-1 fibroblasts, indicating that competent insulin receptors mediate this response. Cellular microinjection of a dominant-negative mutant p21ras protein (N17 ras) or anti-p21ras monoclonal antibody (Y13-259) into HIRc-B cells reduced insulin- and IGF-I-stimulated DNA synthesis by 75-90%. Insulin-induced c-fos protein expression was also inhibited by 74%. Microinjection of oncogenic p21ras (T-24 ras) into HIRc-B cells activated the mitogenic pathway, and coinjection of N17 ras and T-24 ras showed that oncogenic p21ras rescued the cells from the N17 ras blockade. This later finding indicates that T-24 ras acts downstream of N17 ras. In conclusion, 1) microinjection of a dominant interferring ras mutant into quiescent cells abrogated subsequent insulin and IGF-I mitogenic signaling; 2) oncogenic ras protein rescued cells from the N17 ras blockade, indicating that T24 ras action is downstream of the site of N17 inhibition; and 3) p21ras is an intermediate signaling molecule in the insulin/IGF-I signal transduction pathway and is required for gene expression and DNA synthesis.  相似文献   
994.
Übersicht Mittels der Feldtheorie wird das Luftspaltfeld eines zweipoligen dauermagneterregten Gleichstrommotors unter Berücksichtigung des Läuferfeldes bestimmt. Das Anzugsmoment ergibt sich durch Integration der Tangentialkomponente der Maxwellschen Spannung über eine frei gewählte kreiszylindrische Luftspaltfläche, die den Läufer vollständig einschließt.Die numerische Auswertung zeigt den Einfluß des Polbedekkungswinkels und der Magnetisierungsart der betrachteten Magneterregersysteme auf das Anzugsmoment.
Influence of the kind of magnetisation and pole are extension on the starting torques in permanent magnet excited dc motors
Contents The field in the air gap of a two-pole permanent magnet excited dc motor is determined by means of field theory. The starting torque is obtained by integrating the tangential component of the Maxwell Stresses along an arbitrarily selected circular-cylindrical air gap surface which surrounds the rotor completely.The numerical evaluation shows the influence of pole arc extension and the kind of magnetisation of the considered magnetic field systems on the starting torque.
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995.
996.
1. The synthesis and release of nitric oxide may play a role in the pathogenesis of peripheral vasodilatation and hyperdynamic circulation observed in liver cirrhosis. In this work, we analysed the synthesis of nitric oxide by the lympho-mononuclear cells of peripheral blood from patients with chronic alcoholic and non-alcoholic liver disease and we identified the isoform of nitric oxide synthase involved in the increased nitric oxide synthesis. 2. Patients were classified following clinical and histological criteria in non-alcoholic cirrhotic, alcoholic cirrhotic and non-cirrhotic chronic liver disease. We studied clinical and analytical characteristics, haemodynamic parameters and endotoxin levels in these patients. 3. Cirrhotic patients showed an increase of cardiac output and a decrease of peripheral vascular resistance. These patients had higher levels of plasma endotoxin than those observed in the control group. N omega-Nitro-L-arginine methyl ester (L-NAME)-inhibitable nitrite production from mononuclear lymphocyte cells was higher in patients than in the control group, the highest levels being in non-alcoholic cirrhotic patients, and the lowest levels in patients with non-cirrhotic alcoholic liver disease. 4. Immunocytochemistry studies revealed a positive immunoreactivity for the inducible isoform of nitric oxide synthase in lympho-mononuclear cells that was more evident in non-alcoholic than in alcoholic cirrhotic patients. By Northern blot, inducible nitric oxide synthase mRNA expression was observed only in lymphomononuclear cells from non-alcoholic cirrhotic patients. 5. Our patients show a correlation between nitric oxide synthesis, endotoxin levels and haemodynamic parameters. 6. These findings indicate that lympho-mononuclear cell stimulation may play a role in elevated nitric oxide production in hepatic cirrhosis. Thus, this increased nitric oxide synthesis could be implicated in the pathogenesis of the haemodynamic disturbances frequently found in cirrhotic patients. This increase seems to be induced, at least in part, by activation of an inducible isoform of nitric oxide synthase.  相似文献   
997.
Repeated daily intraperitoneal (i.p.) administrations of cadmium (CdCl2, 1 mg/kg per day for 5 days) increased striatal dopamine (DA) release (180% of controls) and turnover (150% of controls) in 13-day-old rats. Cd treatment also increased striatal metallothionein (MT) content (161%), Cd (127%) and lipid peroxidation (LPO, 190%). In addition, Cd treatment decreased striatal tyrosine hydroxylase (TH) activity (-28%), and such an effect may result from D-2 receptor blockade as a consequence of excessive dopamine release, since sulpiride (a specific D-2 receptor antagonist) administration to Cd-treated rats abolished the effect of Cd on TH. No effect was observed on striatal monoamine oxidase (MAO) activity. Dexamethasone (Dx) treatment increased striatal MT content and caused no effect on either DA release or turnover. However, Dx administration prevented the effects caused by Cd, including the increased DA release and enhanced striatal lipid peroxidation. These results indicate that toxic effects on the brain are to be expected as a result of Cd exposure and that Dx administration can attenuate them.  相似文献   
998.
Synthesis of poly(gamma-glutamate) metabolites of natural folates and antifolates is a critical process. Folypolyglutamates are essential for cell proliferation. Polyglutamates of glutamate (Glu)-containing antifolates are often critical for their cytotoxic action and are relevant to antifolate resistance. However, the role of polyglutamate synthesis in selectivity is less clear. We have undertaken a research program to further define the significance of polyglutamate metabolism and to devise ways to exploit this metabolism to achieve greater therapeutic selectivity in cancer chemotherapy. This article briefly reviews several approaches tested thus far. Inhibition of folypolyglutamate synthesis should lead to cell death. Current ornithine (Orn)-containing folate-based inhibitors of the enzyme responsible for their synthesis, folypolyglutamate synthetase (FPGS), are poorly transported, apparently because of interference by the protonated delta-amine. Replacement of Orn with 4, 4-difluoroOrn, the delta-amine of which has a much lower pKa and is thus less protonated at physiological pH, was explored. Since it is unclear how polyglutamylation contributes to selectivity, we explored generic means either to eliminate or to enhance polyglutamylation. The data indicate that substitution for Glu in an antifolate by some Glu analogs in which the gamma-COOH is either altered or replaced (e.g., gamma-tetrazole-Glu) leads to loss of both FPGS substrate activity and binding; antifolate target specificity is unchanged, while uptake is actually enhanced. Substitution of 3,3-difluoroGlu for Glu leads to enhanced polyglutamylation (although probably only to the diglutamate), retention of target specificity, and at least equal uptake. Comparative studies of the same antifolate containing different replacements for Glu, such as gamma-tetrazole-Glu (no polyglutamylation) or 3,3-difluoroGlu (enhanced polyglutamylation), will be useful in exploring the role and significance of polyglutamylation.  相似文献   
999.
Sulfonylureas have, in the past, been reported to have adverse cardiovascular effects. Glimepiride is a new sulfonylurea. In spite of stimulating less insulin secretion, it has, depending on the species, equal or higher blood glucose decreasing activity and according to preliminary studies less cardiovascular activity than glibenclamide. Further studies were performed to confirm the lower cardiovascular activity of glimepiride. The IC50 for inhibition of rilmakalim-activated KATP channel currents in isolated ventricular myocytes was 31.6 nM for glimepiride and 6.8 nM for glibenclamide. In endotoxin shock-rats at a dose of 1 x 2 mg/kg i.v., glibenclamide induced a significantly higher blood pressure increase than glimepiride. At two i.v. doses of 20 mg/kg 4 min apart, in normal rats, glibenclamide produced signs of ischemia in the ECG in nearly all animals, glimepiride almost none, in diabetic rats, glibenclamide produced in all animals a lethal cardiogenic shock preceeded by serious ECG changes, glimepiride only in one fifth of the animals. In open-chest dogs, on intracoronary infusion of equieffective blood glucose-lowering doses, glibenclamide, gliclazide and glimepiride all reduced coronary blood flow, increased coronary resistance, depressed the mechanical activity of the heart, enhanced myocardial O2-extraction, reduced the serum potassium level and induced a moderate endocardial ST-segment elevation, but glimepiride to a significantly less extent than glibenclamide and gliclazide. The presented data confirm that glimepiride at equivalent blood glucose decreasing doses has less cardiovascular activity than conventional sulfonylureas.  相似文献   
1000.
The most important postweaning factorial diseases are at least partly caused by E. coli. The term postweaning coli complex can be subcategorized into the following manifestations: postweaning diarrhoea, edema disease, postweaning wasting and hemorrhagic gastroenteritis. In the presented study the effect of prophylactic zootechnique alone and zoo- and biotechnique in combination was evaluated during the first weeks postweaning. The results showed that combined zoo- and biotechnique is superior to simple zootechnique regarding food conversion (1.41 kg versus 1.73 kg), average daily weight gain (390 g versus 325 g) and postweaning piglet mortality (3.1% versus 4.9%). It is the opinion of the authors that combined postweaning zoo- and biotechnique should be performed in such pig production units where ETEC and/or SLTEC are present.  相似文献   
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