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991.
JH Richardus WC Graafmans SP Verloove-Vanhorick JP Mackenbach 《Canadian Metallurgical Quarterly》1998,36(1):54-66
Priming and recollection are expressions of human memory mediated by different brain events. These brain events were monitored while people discriminated words from nonwords. Mean response latencies were shorter for words that appeared in an earlier study phase than for new words. This priming effect was reduced when the letters of words in study-phase presentations were presented individually in succession as opposed to together as complete words. Based on this outcome, visual word-form priming was linked to a brain potential recorded from the scalp over the occipital lobe about 450 ms after word onset. This potential differed from another potential previously associated with recollection, suggesting that distinct operations associated with these two types of memory can be monitored at the precise time that they occur in the human brain. 相似文献
992.
We contrived a new separation system using a stirred cell charged with uncoupled microsphere similar to the chromatographic separation. Microspheres, carboxylated PS/PMAA and sulfonated PS/PNaSS, were prepared by emulsifier-free emulsion polymerization. To complement the submicron size weakness and the absence of ligands, we employed the latex form, the dispersion of microsphere, and took advantage of interaction relationships between proteins and microspheres. Adsorption isotherm is contemplated to investigate continuous separation behaviours of serum proteins. Selectivity of separation is in the following order: PS/PNaSS-2.0 (high sulfonated) < PS/PNaSS-0.3 (low sulfonated) < PS/PMAA-0.5 (low carboxylated). Unlike previous works on batch separation, not only the adsorbed amount in equilibrium (Cm), but also adsorption coefficient (K), played an important role in continuous separation. Functional groups (carboxyl and sulfonate), induced from the co-monomer, also affected the adsorption behaviours. 相似文献
993.
Delta-9-tetrahydrocannabinol (THC) is frequently found in the blood of drivers involved in automobile accidents, and marijuana use has been associated with impaired field sobriety test performance. The present study used a within-subject design to compare the effects of marijuana (0, 1.77, or 3.95% THC) on equilibrium and simulated driving. Ten marijuana users (seven men, three women) smoked one marijuana cigarette at the beginning of each session. Then 2 min later, they began a 60-min test battery that included subjective effects scales, a computerized test of body sway, a rapid judgment task and brake latency measurement in a driving simulator, critical flicker fusion (CFF), and a choice reaction time task (CRT). Self-report ratings of 'high' and 'drug potency' increased comparably following both active doses. The high, but not the low, dose significantly increased body sway. The high dose also marginally increased brake latency by a mean of 55 ms (P < 0.10), which is comparable to an increase in stopping distance of nearly 5 feet at 60 mph Judgment, CFF, and CRT scores did not differ across dose conditions. The equilibrium and brake latency data with 3.95% THC are similar to prior results in our laboratory in participants with breath alcohol concentrations near 0.05%. 相似文献
994.
995.
996.
RA Lew F Tomoda RG Evans L Lakat JH Boublik LA Pipolo AI Smith 《Canadian Metallurgical Quarterly》1996,118(5):1269-1277
1. The role of the metalloendopeptidase EC 3.4.24.15 (EP 24.15) in peptide metabolism in vivo is unknown, in part reflecting the lack of a stable enzyme inhibitor. The most commonly used inhibitor, N-[1-(R,S)-carboxy-3-phenylpropyl]-Ala-Ala-Tyr-p-aminobenzoate (cFP-AAY-pAB, Ki = 16 nM), although selective in vitro, is rapidly degraded in the circulation to cFP-Ala-Ala, an angiotensin converting enzyme (ACE) inhibitor. This metabolite is thought to be generated by neutral endopeptidase (NEP; EC 3.4.24.11), as the Ala-Tyr bond of cFP-AAY-pAB is cleaved by NEP in vitro. In the present study, we have examined the role of NEP in the metabolism of cFP-AAY-pAB in vivo, and have tested a series of inhibitor analogues, substituted at the second alanine, for both potency and stability relative to the parent compound. 2. Analogues were screened for inhibition of fluorescent substrate cleavage by recombinant rat testes EP 24.15. D-Ala or Asp substitution abolished inhibitory activity, while Val-, Ser- and Leu-substituted analogues retained activity, albeit at a reduced potency. A relative potency order of Ala (1) > Val (0.3) > Ser (0.16) > Leu (0.06) was observed. Resistance to cleavage by NEP was assessed by incubation of the analogues with rabbit kidney membranes. The parent compound was readily degraded, but the analogues were twice (Ser) and greater than 10 fold (Leu and Val) more resistant to cleavage. 3. Metabolism of cFP-AAY-pAB and the Val-substituted analogue was also examined in conscious rabbits. A bolus injection of cFP-AAY-pAB (5 mg kg-1, i.v.) significantly reduced the blood pressure response to angiotensin I, indicating ACE inhibition. Pretreatment with NEP inhibitors, SCH 39370 or phosphoramidon, slowed the loss of cFP-AAY-pAB from the plasma, but did not prevent inhibition of ACE. Injection of 1 mg kg-1 inhibitor resulted in plasma concentrations at 10 s of 23.5 microM (cFP-AAY-pAB) and 18.0 microM (cFP-AVY-pAB), which fell 100 fold over 5 min. Co-injection of 125I-labelled inhibitor revealed that 80-85% of the radioactivity had disappeared from the circulation within 5 min, and h.p.l.c. analysis demonstrated that only 25-30% of the radiolabel remained as intact inhibitor at this time. Both analogues were cleared from the circulation at the same rate, and both inhibitors blunted the pressor response to angiotensin I, indicative of ACE inhibition. 4. These results suggest that both NEP and other clearance/degradation mechanisms severely limit the usefulness of peptide-based inhibitors such as cFP-AAY-pAB. To examine further EP 24.15 function in vivo, more stable inhibitors, preferably non-peptide, must be developed, for which these peptide-based inhibitors may serve as useful molecular templates. 相似文献
997.
998.
Meteorology is often thought of as a field with highly developed techniques for forecasting rare and severe events. Risk assessment of another type of rare and severe event—violence to others—occurs in mental health law. The analogy between these 2 forms of risk assessment is explored in this article. How meteorologists go about assessing the risk of harmful weather is described. Implications from the meteorological analogy are drawn for 1 aspect of violence prediction that is routinely ignored in mental health law: the communication of risk "forecasts." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
1000.
GA Velders JC Kluin-Nelemans CJ De Boer J Hermans EM Noordijk E Schuuring MH Kramer WA Van Deijk JB Rahder PM Kluin JH Van Krieken 《Canadian Metallurgical Quarterly》1996,14(4):1269-1274
PURPOSE: From a population-based non-Hodgkin's lymphoma (NHL) registry, 41 patients with mantle cell lymphoma (MCL) -- a recently defined distinct B-cell NHL -- were selected and compared with patients with low- or intermediate-grade NHL from the same registry. PATIENTS AND METHODS: The incidence and behavior of MCL in the area of the Comprehensive Cancer Center West (CCCW) from 1981 to 1989 were analyzed. Age, performance, tumor bulk, extranodal localization, stage, response to therapy, and survival were registered. Expression of cyclin D1 protein and Ki-67 were measured in 29 patients. RESULTS: MCL made up 3.7% of NHLs. The median age was 68 years, and the male-to-female ratio was 1.6:1. Seventy-eight percent presented with stage IV, with the majority having bone marrow involvement. The complete response (CR) rate was 32% (13 of 41), with a median duration of 25 months. The median overall survival time was 31.5 months. The International Prognostic Index identified five patients with a low-risk score and a median survival time of 93+ months. In 23 of 29 patients, cyclin D1 overexpression was present, without any relation to overall or disease-free survival. In contrast, a proliferative index less than 10% was significantly related to a better overall survival time (50 v 24 months). CONCLUSION: MCL is a disease of the elderly, who present with widespread disease and with a poor response to therapy. Although it harbors features of an indolent NHL, it behaves clinically as an aggressive NHL with a short overall survival time. 相似文献