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71.
Killen Joel D.; Fortmann Stephen P.; Schatzberg Alan F.; Hayward Chris; Sussman Lisa; Rothman Micol; Strausberg Laura; Varady Ann 《Canadian Metallurgical Quarterly》2000,68(5):883
Smokers (N?=?224) were randomized to 1 of 3 groups: (a) transdermal system (TNS) + placebo; (b) TNS + paroxetine (20 mg); (c) TNS + paroxetine (40 mg). Assignment to treatment was double-blind. Nicotine patch (TNS) treatment was provided for 8 weeks; paroxetine or placebo was provided for 9 weeks. Abstinence rates at Weeks 4, 10, and 26 were as follows: (a) TNS + placebo: 45%, 36%, and 25%; (b) TNS + paroxetine (20 mg): 48%, 33%, and 21 %; (c) TNS + paroxetine (40 mg): 57%, 39%, and 27%. The differences were not statistically significant. The combined treatment was more effective in reducing both craving and depression symptoms associated with smoking cessation. A subgroup analysis comparing compliant participants was also conducted. Abstinence rates at Weeks 4, 10, and 26 were as follows: (a) TNS + placebo: 46%, 35%, and 24%; (b) TNS + paroxetine (20 mg): 64%, 43%, and 33%; (c) TNS + paroxetine (40 mg): 74%, 51%, and 38%. The differences between paroxetine groups and placebo at Week 4 were statistically significant. Although paroxetine may add value to the current standard of care in excess of potential risk, more conclusive evidence is needed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
N6-(p-Azidobenzyl)adenosine (ABA) and nitrobenzylthioinosine (NBMPR) were employed as covalent probes of the nucleoside transport mechanism in human erythrocytes. NBMPR, a potent inhibitor of nucleoside transport, binds tightly (KD 0.3-1 nM) to specific sites on nucleoside transporter elements. ABA, a less potent inhibitor of uridine influx, competitively inhibited NBMPR binding (Ki 15 nM). [3H]ABA was bound tightly (KD 13.4 nM) but reversibly to sites on erythrocytes which appeared to be those which bind NBMPR. ABA binding was inhibited by uridine and adenosine. Irradiation with UV light caused site-bound [3H]ABA on erythrocyte membranes to become covalently bound and, similarly, photoactivation resulted in covalent attachment of membrane-bound [3H]NBMPR. In the presence of dithiothreitol, a free radical scavenger, photoactivation of the site-bound 3H-ligand on membranes depleted of extrinsic membrane proteins resulted in selective incorporation of 3H into band 4.5 of the membrane polypeptides which were resolved on sodium dodecyl sulfate-polyacrylamide gel electropherograms. This result, when considered with previous findings, indicates that the NBMPR-binding component of the nucleoside transport mechanism (or the entire mechanism, if the NBMPR site is an integral part) is a band 4.5 polypeptide. 相似文献
73.
A group of public health scientists from the United States and The Netherlands met at a Bicentennial Round Table Conference December 1-2, 1982, to discuss the latest developments in immunization against infectious diseases, focusing on pertussis, poliomyelitis, measles, and rubella. The major differences in immunization practices in the two countries are: (a) In The Netherlands, inactivated polio vaccine is used exclusively; in the United States, the oral polio vaccine is used. Polio-myelitis has virtually disappeared from both countries. (b) In The Netherlands, the pertussis component of DTP (diphtheria, tetanus, pertussis) is not given to children over the age of 1 year, whereas in the United States, it is given to children up to their seventh birthday. (c) Rubella vaccine is given only to girls at ages 11-12 years in The Netherlands, but to all children at ages 12-15 months in the United States. (d) Mumps vaccine is not administered to children in The Netherlands, but in the United States it is given routinely to children at 12-15 months (in combination with measles and rubella vaccine). The participants concluded that both the United States and The Netherlands have effective immunization programs that have significantly reduced the impact of these diseases. 相似文献
74.
In situ, High-Resolution Measurement of Dissolved Sulfide Using Diffusive Gradients in Thin Films with Computer-Imaging Densitometry 总被引:6,自引:0,他引:6
The technique of diffusive gradients in thin films (DGT) has been developed for the measurement of dissolved sulfide. Sulfide species from the sampled waters diffuse through a polyacrylamide hydrogel and then react with pale yellow AgI((s)), incorporated at the surface of a second gel, to form black Ag(2)S((s)). The accumulated sulfide can be measured with a conventional purge-and-trap method followed by colorimetry (methylene blue). This enables the dissolved-sulfide concentration to be calculated under suitable conditions. Alternatively, the color change in the accumulating gel can be used to measure sulfide. A conventional flat-bed scanner, allied to imaging software, provided a densitometric measurement that was quantitatively related to the amount of sulfide accumulated. DGT measurements on synthetic solutions accurately determined the sulfide concentration (95% recovery), thereby confirming the unobstructed diffusion of HS(-) through the gel. The accumulated mass was inversely proportional to the diffusion-layer thickness as theoretically predicted. With the selected geometry, the limit of detection of the densitometric procedure for a 24-h deployment was 0.13 μmol L(-)(1), and the maximum concentration measurable was 60 μmol L(-)(1). When used in anoxic lacustrine waters, DGT provided sensible concentrations. It was also used to measure depth profiles at submillimeter resolution in estuarine surface sediments. 相似文献
75.
76.
The relative optical reflectance and electrical resistivity have been measured of thick films (~1μm) deposited by sputtering Al in a planar magnetron using Ar and Ar + O2 mixtures. The results obtained have a practical value in indicating the power input and related deposition rate required for given discharge conditions to obtain Al-films with a high reflectance and bulk resistivity. 相似文献
77.
Bradley R O'Toole DT Wells DE Anderson PH Hartley P Berrett S Morris JE Insch CG Hayward EA 《Meat science》1987,19(1):39-51
Ten healthy beef cattle in a commercial abbatoir were treated intravenously before slaughter with a commercial papain-based tenderising injection (Pro Ten). Animals were observed for behavioural and clinical abnormalities following treatment. Serum enzyme activities were measured pre-treatment and post-treatment immediately pre-slaughter < 6 min later to detect liver and muscle damage. Carcases were examined grossly post mortem. Histological examination of liver, kidney and muscle followed. Nine contemporary, age-matched controls were similarly examined. It was concluded that ProTen treatment did not cause any detectable hepatocellular or renal damage and there was no significant difference in the parameters examined between treated and untreated cattle. A decision to ban the use of ProTen in cattle could not therefore be based on the premise that it interfered with the animal's welfare in the period following injection under the conditions pertaining in this experiment. 相似文献
78.
Mouse BC3H1 myogenic cells and a bi-functional chemical cross linking reagent were utilized to investigate the polymerization of newly-synthesized vascular smooth muscle (alpha-actin) and non-muscle (beta- and gamma-actin) actin monomers into native F-actin filament structures during myogenesis. Two actin dimer species were identified by SDS-PAGE analysis of phenylenebismaleimide-cross linked fractions of BC3H1 myoblasts and myocytes. P-dimer was derived from the F-actin-enriched, detergent-insoluble cytoskeleton. Pulse-chase analysis revealed that D-dimer initially was associated with the cytoskeleton but then accumulated in the soluble fraction of lysed muscle cells that contained a non-filamentous or aggregated actin pool. Immunoblot analysis indicated that non-muscle and smooth muscle actins were capable of forming both types of dimer. However, induction of smooth muscle alpha-actin in developing myoblasts coincided with an increase in D-dimer level which may facilitate actin stress fiber assembly. Smooth muscle alpha-actin was rapidly utilized in differentiating myoblasts to assemble extraction-resistant F-actin filaments in the cytoskeleton whereas non-muscle beta- and gamma-actin filaments were more readily dissociated from the cytoskeleton by an extraction buffer containing ATP and EGTA. The data indicate that cytoarchitectural remodeling in developing BC3H1 myogenic cells is accompanied by selective actin isoform utilization that effectively segregates multiple isoactins into different sub-cellular domains and/or supramolecular entities. 相似文献
79.
Weems Carl F.; Hayward Chris; Killen Joel; Taylor C. Barr 《Canadian Metallurgical Quarterly》2002,111(3):471
This investigation sought to expand existing knowledge of anxiety sensitivity in a sample of high school students (N = 2,365) assessed over 4 years. The stability of anxiety sensitivity levels across assessment periods was examined, and cluster analyses were used to identify different developmental pathways in levels of anxiety sensitivity. Groups of adolescents with stable low, stable high, and escalating anxiety sensitivity levels were identified. Adolescents with stable high or escalating anxiety sensitivity were significantly more likely to report experiencing a panic attack than individuals with stable low anxiety sensitivity. Results also indicated that Asian and Hispanic adolescents tended to report higher anxiety sensitivity but that their anxiety sensitivity was less strongly associated with panic than that of Caucasian adolescents. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.