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Studies are presented of the effect of procaine group anesthetics on rat brain synaptosome stability to dodecyl sulfate and on catalytic properties of the membrane bound alkaline phosphatase. The dose curves of detergent stability are characterized by two maxima, one at 3.10(-4) M for tetracaine, 2.10(-6) M for lidocaine and 5.10(-5) M for procaine; the other being at 10(-3) M for all anesthetics. The curves of Vmax and KM versus procaine concentration to exhibit the minimum at 5.10(-7) M and maximum at 3,2.10(-6) M. Procaine at 5.10(-7) M increases enthalpy and enthropy of membraneous alkaline phosphatase. It is suggested that interactions between anesthetics and centers of high affinity lead to synaptosome structural rearrangements, which affect the properties of membraneous enzymes.  相似文献   
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The efficacy of meditation-relaxation techniques has been widely researched in the laboratory, but their effectiveness for management of stress in organizational settings is still relatively unexplored. The present study compared relaxation and control conditions as part of a program of stress-reduction in industry. A total of 154 New York Telephone employees self-selected for stress learned one of three techniques--clinically standardized meditation (CSM), respiratory one method meditation (ROM) or progressive relaxation (PMR)--or served as waiting list controls. At 5.5 months, the treatment groups showed clinical improvement in self-reported symptoms of stress, but only the meditation groups (not the PMR group) showed significantly more symptom reduction than the controls. The meditation groups had a 78% compliance rate at 5.5 months with treatment effect seen whether subjects practiced their techniques frequently or occasionally. The safe and inexpensive semi-automated meditation training has considerable value for stress-management programs in organizational settings.  相似文献   
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Three cases of long bone reconstruction with vascularised fibula grafts are described. Hypertrophy of the graft did not occur after a follow-up of 3-5 years. Three different kinds of stress shielding appeared to prevent transformation of the graft.  相似文献   
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Cyclosporine (CsA) and some of its metabolites (M9, M17, M18, M21) have been determined by means of an LC-MASS method in eight psoriatic patients developing nephrotoxicity. In comparison with a control group (15 psoriatics who after the same period of time, with the same daily dose, did not develop nephrotoxicity) they showed an increase of CsA metabolites, especially M17. Because M17 blood concentrations in the nephrotoxic group tended to be higher than in the control group from the first week of treatment we suggest that M17 might be considered a marker of ongoing nephrotoxicity.  相似文献   
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The accuracy of water T2 maps generated from a fast spin-echo (FSE) sequence was compared with data obtained by conventional single and multi-echo spin-echo pulse sequences using a commercial gel phantom. Spatially localized stimulated echo acquisition mode (STEAM) proton spectroscopy was also used to confirm the reported water T2 values of the gels contained in the phantom. The FSE sequence was shown to be superior in accuracy to both the single and multi-echo spin echo sequences and comparable to STEAM, producing results that were within 10% of known values. The effectiveness of the FSE sequence was further demonstrated by generating T2 maps of the normal and diseased prostate in clinically acceptable imaging times, resulting in comparable T2 values to those obtained using STEAM. Accurate quantitative T2 maps can be produced with the FSE sequence.  相似文献   
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Using a recently developed gas chromatography and mass spectrometry method to determine whole-blood cyclophosphamide (CP) and 4-hydroxycyclophosphamide/aldophosphamide (4-HO-CP/AP) concentrations, we investigated their pharmacokinetics in women receiving CP therapy. Patients (n = 18) received one or two courses of CP: (a) a 90-min i.v. infusion (4 g/m2) followed by a 96-h i.v. infusion (6 g/m2) in combination with high-dose thiotepa; or (b) a 96-h i.v. infusion (6 g/m2) in combination with high-dose thiotepa. Whole-blood exposures to CP [area under the whole blood concentration versus time curve (AUCCP)] and 4-HO-CP/AP (AUC4HOCP) between courses 1 and 2 were compared after normalization to dose (g/m2). A nonproportional increase was observed for the AUCCP between the first course [1112 micrometer. h/g/m2 +/- 14% coefficient of variation (CV)] and the second course (1579 micrometer . h/g/m2 +/- 28% CV) (P < 0.001). In contrast, the AUC4HOCP (27 micrometer . h/g/m2 +/- 25% CV) determined for the first course was 29% higher than the AUC4HOCP (21 micrometer . h/g/m2 +/- 26% CV) for the second course (P < 0.01). The interpatient whole-blood exposures to both CP and 4-HO-CP/AP were remarkably consistent in this patient population with percent CVs ranging from 14 to 28%. Because thiotepa (800 mg/m2) was administered simultaneously with CP during the second course of treatment, possible inhibition of CP metabolism by thiotepa was investigated using human liver microsomes in vitro. IC50 values determined for inhibition of CP metabolism in three individual liver donors ranged from 1.0 to 40 micrometer. However, the clinical relevance of this observation has not been established.  相似文献   
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