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941.
The effects of three monomethoxyamphetamines, dl-para-methoxyamphetamine (dl-PMA), dl-meta-methoxyamphetamine (dl-MMA) and dl-ortho-methyoxyamphetamine (dl-OMA), and d-amphetamine (d-A) on the myoclonic twitch activity (MTA) of PMA, MMA and d-A were found to increase the MTA but OMA was ineffective. The increased MTA induced by d-A was not influenced by the blockade of 5-hydroxytryptamine (5-HT) receptor by methysergide or inhibition of 5-HT synthesis by para chlorophenylalamine (PCPA) but was reduced by haloperidol which blocked the dopamine receptor. On the other hand, the increased MTA produced by PMA was not influenced by haloperidol but was reduced by methysergide and PCPA. The increased MTA induced by MMA was not effectively blocked by either PCPA or haloperidol but was blocked by the combination of both PCPA and haloperidol. The results indicate that whereas the increased MTA produced by d-A is not dependent on the availability of 5-HT, PMA exerts by a release of 5-HT and that the MMA effect is due to a release of both 5-HT and dopamine. High doses of PMA and MMA increased the locomotor activity arevious biochemical findings that PMA releases 5-HT in brain tissue and suggests that PMA exerts its pharmacological effects by releasing 5-HT. 相似文献
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V R Katti S K Gupta A K Debnath N C Jaydeven L C Gupta MK Gupta 《Bulletin of Materials Science》1991,14(2):423-427
The deposition of yttria-stabilized zirconia (YSZ) as buffer layer on (100) silicon has been studied by rf sputtering with
a view to subsequently preparing superconducting films of YBa2Cu3O
x
on it. As-deposited films were found to be (100) oriented. The thermal mismatch and reaction between Si and YSZ at high temperatures
were found to give rise to cracks in the films. Grain growth of buffer layer on annealing helped in the formation of superconducting
phase. 相似文献
945.
The contribution R
s of a superconductor S to the resistance of a superconductor-normal metal (S-N) system is calculated. The case when the characteristics of metals S and N are different (different mean free path, density of states, etc.) is considered. It is shown that the value and temperature dependence of R
s differ from those obtained earlier. The resistance of the S-N-S system and of a system consisting of alternating S-N layers is calculated. The excess current I
exc in contacts S1-c-S2 (S1,2 are different superconductors, c denotes a narrow constriction) is determined. The influence of magnetic field and of paramagnetic impurities on the value of the I
exc is found. 相似文献
946.
JC Borleffs M Bosschaert HM Vrehen MM Schneider J van Strijp MK Small KM Borkett 《Canadian Metallurgical Quarterly》1998,20(4):722-736
The safety profile, tolerability, pharmacodynamics, and pharmacokinetics of four doses of recombinant human granulocyte colony-stimulating factor (filgrastim) were assessed in healthy volunteers in a double-masked, placebo-controlled, parallel-group trial. Healthy subjects received subcutaneous injections of filgrastim 75 microg (n = 8), 150 microg (n = 4), 300 microg (n = 4), 600 microg (n = 8), or placebo (n = 6) daily for 10 consecutive days. Blood samples were drawn daily immediately before the injection and on days 1 and 10 serially throughout the day. Increased absolute neutrophil counts (ANCs) were seen within 90 minutes of drug administration in subjects in all dose groups, peaking approximately 12 hours after administration. This increase was dose related in subjects in the three lower dose groups. The time to peak ANC on day 10 was approximately 9 hours, with a daily ANC profile in all four dose groups that was similar to the profile on day 1. In all dose groups, ANCs were near baseline within 48 hours of discontinuation of filgrastim. Mild, reversible thrombocytopenia was reported in 4 of 10 subjects in the highest dose group. Two subjects in the filgrastim 600-microg group were withdrawn for adverse events. Filgrastim had a good safety profile and caused dose-related increases in ANC when administered to healthy volunteers for up to 10 days. 相似文献
947.
Responding to demands that nursing leaders conduct business in creative proactive ways, the authors of this department share the work of The Robert Wood Johnson Foundation's national program, Colleagues in Caring: Regional Collaboratives for Nursing Work Force Development. The purpose of this initiative is to enhance regional and state collaborative planning and implement actions and policies to address the rapid changes occurring in the United States nursing labor market. This department, edited by Mary Fry Rapson, PhD, RN, CS, National Program Director and Rebecca B. Rice, EdD, RN, National Deputy Director, presents the ongoing work of the program, highlighting the work of the 20 individual collaboratives. Regional approaches to the expected program outcomes and specific challenges and opportunities that are unique to each region's environment are included. 相似文献
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This article describes a method of determining the long-term strength of plastics under a combined influence of mechanical loads (uniaxial tension), temperature, and aggressive media. Data are reported on the time-to-rupture of polypropylene in air, water, sulfuric and hydrochloric acids, and a 10% NaOH solution at 20–140° C at stresses of up to 0.6 UTS. 相似文献