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1. Nimodipine (30 mg three times daily) and diazepam (10 mg once daily), were given orally to 24 elderly healthy subjects in a randomized, non-blinded, threefold-crossover study. Each of the three treatment periods lasted 5 days separated by 2 week washout phases. 2. Plasma concentrations of nimodipine and diazepam were not affected by the combined treatment. 3. No clinically relevant changes in haemodynamics, ECG recordings, clinical chemistry or haematology were observed after all of the three treatments. The overall frequency of side effects was lowest during monotherapy with nimodipine and highest during diazepam monotherapy. 4. In the test of subjective rating of tiredness (VAS) and the Pauli calculation test, diazepam, alone and with nimodipine co-medication, produced an increase in tiredness and a clear reduction in performance and endurance. After nimodipine monotherapy an improvement was observed only in the Pauli test. Using the critical flicker fusion frequency test (CFF) significant decrements in performance were found after diazepam monotherapy only. 5. In summary, there was no evidence that either nimodipine or diazepam affected the pharmacokinetics, safety and tolerance of each other. However, the CNS-effects of diazepam were compensated partially by nimodipine.  相似文献   
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A bone graft, taken from the medial part of the radial epiphysis can be pedicled on the radial branch of the volar carpal arch, freed back to its origin. The graft can be transferred into the proximal row of the carpus to fill up a loss of bony substance or to provide vascularised bone. This permits the treatment of chronic pseud-arthrosis of the scaphoid where a Matti-Russe operation has failed. In the first three cases operated upon, favourable results have been obtained.  相似文献   
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Background. Intraperitoneal phagocytes play an important role in local host defence to prevent CAPD peritonitis. The intracellular calcium [Ca2+]i is thought to be involved in the regulation of various cell functions. This study therefore investigates the effect of lactate-based dialysis solution (LBDS) and bicarbonate-based dialysis solution (BBDS) on cytosolic free calcium mobilization and superoxide production (SP) as important steps in signal transduction and bacterial killing. Methods. We studied changes in [Ca2+]i and SP following stimulation with N-formyl-methionyl-leucyl-phenylalanine (fMLP) in polymorphonuclear neutrophils (PMNs) incubated in either LBDS-pH 5.2, LBDS adjusted to pH 7.4, 1:10 diluted spent and fresh LBDS or BBDS-pH 7.4 with different glucose concentrations, comparing the data with cells treated with Hanks buffer (HBSS) pH 7.4 as control. To elucidate the effect of glucose and lactate PMNs were additionally incubated in HBSS-pH 7.4, containing glucose (HBSS-Glu-pH 7.4) or lactate (HBSS-Lact-pH 7.4) in the same concentrations as contained in CAPD solutions and tested as above. PMNs were isolated from healthy blood donors and incubated with dialysis solution 10 min prior to stimulation with fMLP. Results. [Ca2+]i mobilization and SP were completely inhibited in PMNs incubated in LBDS pH 5.2. pH adjustment of LBDS to 7.4 and 1:10 dilution of spent and fresh LBDS corrected some of the suppression of the calcium influx and superoxide production. BBDS pH 7.4, however, preserved physiological cell function significantly better at low (1.5 and 2.3%) glucose concentrations. Conclusion. In comparison to conventional lactate-based dialysis solution, pH adjusted and 1:10 diluted LBDS, bicarbonate-based dialysis solution is more biocompatible since it preserves significantly better neutrophil cell functions.  相似文献   
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In order to establish an univariate nonparametric pediatric tolerance region platelet function has been investigated in 105 healthy children and adolescents. In comparison to adult normal values, the bleeding time is shortened, spontaneous platelet aggregation is enhanced as well as collagen-induced platelet aggregation. 30% of the children showed an increased disaggregation in ADP-induced aggregation. A slight delay was found in the spreading of thrombocytes. Platelet volume shifted to the left. Values of beta-thromboglobulin were raised. Compared to adult values no alterations could be found in platelet shape-change. Changes of platelet functions were more apparent in the younger children.  相似文献   
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Induction of mucosal tolerance by inhalation of soluble peptides with defined T cell epitopes is receiving much attention as a means of specifically down-regulating pathogenic T cell reactivities in autoimmune and allergic disorders. Experimental autoimmune encephalomyelitis (EAE) induced in the Lewis rat by immunization with myelin basic protein (MBP) and Freund's adjuvant (CFA) is mediated by CD4+ T cells specific for the MBP amino acid sequences 68-86 and 87-99. To further define the principles of nasal tolerance induction, we generated three different MBP peptides (MBP 68-86, 87-99 and the non- encephalitogenic peptide 110-128), and evaluated whether their nasal administration on day -11, -10, -9, -8 and -7 prior to immunization with guinea pig MBP (gp-MBP) + CFA confers protection to Lewis rat EAE. Protection was achieved with the encephalitogenic peptides MBP 68-86 and 87-99, MBP 68-86 being more potent, but not with MBP 110-128. Neither MBP 68-86 nor 87-99 at doses used conferred complete protection to gp-MBP-induced EAE. In contrast, nasal administration of a mixture of MBP 68-86 and 87-99 completely blocked gp-MBP-induced EAE even at lower dosage compared to that being used for individual peptides. Rats tolerized with MBP 68-86 + 87-99 nasally showed decreased T cell responses to MBP reflected by lymphocyte proliferation and IFN-gamma ELISPOT assays. Rats tolerized with MBP 68-86 + 87-99 also had abrogated MBP-reactive IFN-gamma and tumor necrosis factor-alpha mRNA expression in lymph node cells compared to rats receiving MBP 110-128 nasally, while similar low levels of MBP-reactive transforming growth factor-beta and IL-4 mRNA expressing cells were observed in the two groups. Nasal administration of MBP 68-86 + 87-99 only slightly inhibited guinea pig spinal cord homogenate-induced EAE, and passive transfer of spleen mononuclear cells from MBP 68-86 + 87-99-tolerized rats did not protect naive rats from EAE. Finally, we show that nasal administration of MBP 68-86 + 87-99 can reverse ongoing EAE induced with gp-MBP, although higher doses are required compared to the dosage needed for prevention. In conclusion, nasal administration of encephalitogenic MBP peptides can induce antigen-specific T cell tolerance and confer incomplete protection to gp-MBP-induced EAE, and MBP 68-86 and 87-99 have synergistic effects. Non-regulatory mechanisms are proposed to be responsible for tolerance development after nasal peptide administration.   相似文献   
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