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121.
Infusion of the GPIIb/IIIa-inhibitor MK383 inhibits thrombin generation in platelet rich plasma by interfering with the production of platelet procoagulant phospholipid exposure. The effect is similar to that of 0.2 U/ml of heparin. Heparin infusion, well known to inhibit thrombin generation by fostering antithrombin activity, inhibits the formation of platelet-derived procoagulant microparticles, probably by decreasing the formation of free thrombin, which, under our circumstances, is the main platelet activator. 相似文献
122.
A Antonini JR Moeller T Nakamura P Spetsieris V Dhawan D Eidelberg 《Canadian Metallurgical Quarterly》1998,51(3):803-810
OBJECTIVE: To identify regional metabolic brain networks related specifically to the presence of tremor in PD. BACKGROUND: The pathophysiology of parkinsonian tremor is unknown. Because tremor in PD occurs mainly in repose, we used resting state PET with 18F-fluorodeoxyglucose (FDG) to identify specific metabolic brain networks associated with this clinical manifestation. METHODS: We studied two discrete groups of eight PD patients with and without tremor using FDG/PET. Both patient groups were matched for gender, age, and Unified Parkinson Disease Rating Scale ratings for akinesia and rigidity. Ten normal volunteer subjects served as controls. RESULTS: Network analysis with the Scaled Subprofile Model was performed in two steps. 1) We computed the expression of the PD-related pattern (PDRP) identified by us previously in each of the PD patients and control subjects. Although PDRP subject scores were abnormally elevated in the combined PD cohort (p < 0.005), these values did not differ in the PD patient groups with and without tremor (p = 0.36). 2) We used SSM to analyze the data from the combined PD cohort comprising both patient groups. We found that PD patients with tremor were characterized by increased expression of a metabolic network comprising the thalamus, pons, and premotor cortical regions. Subject scores for this pattern were elevated in the tremor group compared with the atremulous patient group and the normal control group (p < 0.005). CONCLUSIONS: The findings suggest that PD patients with tremor are characterized by distinct increases in the functional activity of thalamo-motor cortical projections. Modulation of this functional anatomic pathway is likely to be the mechanism for successful interventions for the relief of parkinsonian tremor. 相似文献
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JS Plummer KA Berryman C Cai WL Cody J DiMaio AM Doherty JJ Edmunds JX He DR Holland S Levesque DR Kent LS Narasimhan JR Rubin ST Rapundalo MA Siddiqui AJ Susser Y St-Denis PD Winocour 《Canadian Metallurgical Quarterly》1998,8(23):3409-3414
The synthesis and antithrombotic activity of a series of nonpeptide bicyclic thrombin inhibitors is described. We have explored the SAR with modifications to the P1 site. The introduction of arginine mimetics at the P1 site led to potent and selective thrombin inhibitors. 相似文献
125.
S Maixner R Tandon A Eiser S Taylor JR DeQuardo J Shipley 《Canadian Metallurgical Quarterly》1998,155(11):1600-1602
OBJECTIVE: The authors sought to replicate and extend previous observations of improvement in some EEG sleep measures during the course of antipsychotic treatment in schizophrenia patients. METHOD: Fourteen medication-free patients with schizophrenia underwent 2 nights of sleep EEG monitoring before and after 3-4 weeks of treatment with clinically determined doses of haloperidol or thiothixene. RESULTS: Measures of sleep continuity improved consistently. REM latency increased, although five of 14 patients continued to exhibit short REM latencies (less than 60 minutes). Stage 3 sleep increased during neuroleptic treatment, while stage 4 sleep did not change. CONCLUSIONS: These data demonstrate partial improvement of some but not all EEG sleep measures in schizophrenic patients through the course of neuroleptic treatment. They suggest that shortened REM latency and disturbed sleep continuity might represent reversible state abnormalities, while reduced slow-wave sleep may represent a more persistent trait abnormality in schizophrenia. 相似文献
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JR García Fernández MA montalbán ML Martín MC Ortiz MA Martínez A García Marcilla 《Canadian Metallurgical Quarterly》1998,43(5):430-432
Acute nonoliguric renal failure developed in a 13-year-old girl, 1 month after the institution of isoniazid therapy because of a positive tuberculin test at school screening. A renal biopsy demonstrated severe crescentic glomerulonephritis with focal interstitial changes. Discontinuation of isoniazid and a short course of steroids and cyclophosphamide therapy were followed by complete recovery. Whereas isoniazid has been shown to induce a lupus-like syndrome and antihistone antinuclear antibodies, our patient displayed none of the clinical or immunological features that are characteristic of drug-induced lupus. Furthermore, none of the identifiable causes for crescentic glomerulonephritis was evident in this girl. To the best of our knowledge this is the first report suggesting a possible association of crescentic glomerulonephritis to isoniazid treatment. 相似文献
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TM Officer R Pellegrino V Brusasco JR Rodarte 《Canadian Metallurgical Quarterly》1998,85(5):1982-1988
We compared four algorithms by using least squares regression for determination of pulmonary resistance and dynamic elastance in subjects with emphysema, normal subjects, and subjects with asthma before and after bronchoconstriction. The four methods evaluated include 1) a single resistance and elastance, 2) separate resistances and elastances for each half breath, 3) separate inspiratory and expiratory resistances with a single elastance, and 4) separate inspiratory and expiratory resistances, an expiratory volume interaction term, and a single elastance. All methods gave comparable results in normal and asthmatic subjects. We found expiratory resistance was larger than inspiratory resistance in normal and asthmatic subjects during control conditions, but inspiratory resistance was higher than expiratory resistance in subjects who experienced severe bronchoconstriction in response to methacholine. In subjects who are flow limited, method 2 gives a higher inspiratory resistance than would be computed by assuming that the elastic pressure-volume curve passes through the zero-flow points. Methods 1 and 3 overestimate dynamic elastance and inspiratory resistance. Method 4 appears to identify flow limitation and dynamic hyperinflation and gives a good measure of inspiratory resistance and dynamic elastance. 相似文献