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561.
DN Reddy PG Reddy W Xue HC Minocha MJ Daley F Blecha 《Canadian Metallurgical Quarterly》1993,37(1):25-38
Three experiments, using 85 crossbred beef calves, were conducted to evaluate the adjuvanticity of single, multiple, and combined doses of recombinant bovine IL-1 beta (rBoIL-1 beta) and recombinant bovine IL-2 (rBoIL-2), with a modified-live bovine herpesvirus-1/parainfluenza-3 (BHV-1/PI-3) virus vaccine and a killed bovine viral diarrhea (BVD) virus vaccine. Cytokines were administered intramuscularly at vaccination but at different injection sites. All cytokine treatments increased non-major histocompatibility complex (MHC)-restricted cytolytic capability of peripheral blood mononuclear cells (PBMC) against virus-infected target cells and serum neutralizing (SN) antibody titers to BHV-1 and BVD virus. Multiple, consecutive injections of rBoIL-2 generally showed the greatest adjuvant effect, and no additive effect was observed when rBoIL-1 beta and rBoIL-2 were administered together. In a challenge experiment, calves were vaccinated with a modified-live BHV-1/PI-3 vaccine and infected with BHV-1 on Day 21. Cytokine-treated calves had higher SN antibody titers to BHV-1 than did the control calves at the time of challenge. Calves that were administered rBoIL-2 on 5 consecutive days shed less BHV-1 and had the highest SN antibody titer to BHV-1 (Day 28). These data suggest that rBoIL-1 beta and rBoIL-2 may be useful immunoadjuvants for bovine respiratory disease virus vaccines. 相似文献
562.
Eighteen male social drinkers underwent four training sessions during which they ingested two colour-coded drinks (red or blue, balanced for drink type); one containing alcohol (aliquots of 0.1 g/kg) and the other placebo (aliquots of orangeade). Following the training sessions, subjects were presented with both drinks, and instructed to choose the drink they felt like consuming and to indicate their preference for their chosen drink over the other drink. In addition, they were instructed to consume the first drink but that all subsequent drinks (total of six drinks), offered at 10-min intervals, were optional. A number of trait characteristics were assessed including alcohol outcome expectancies, drinking habits and personality traits. The acute effects of alcohol on mood was also evaluated by comparing subjective ratings following alcohol and placebo during the training sessions. Of the 18 subjects, 12 chose alcohol at least once ('samplers'), whereas six never chose alcohol ('non-samplers'). Over the three sessions, however, alcohol and placebo were chosen equally. When alcohol was chosen, subjects drank significantly more than when placebo was chosen, which may be consistent with a priming effect of drinking alcohol. The amount of alcohol drunk was seen to correlate with the alcohol expectancy factor 'sociability'. Subjective reports of feeling 'alert', 'clear-headed', 'quick-witted', and 'attentive' all showed a main effect of choosing behaviour (i.e. 'samplers'/'non-samplers'). Further analysis indicated that this effect was due to 'samplers' reporting increased subjective ratings of these mood states following the ingestion of alcohol compared to 'non-samplers'. These increased subjective ratings were also positively correlated with the amount of alcohol consumed by the subjects during the choice procedure. No other relationships were found between the amount of alcohol consumed and any of the other state or trait measures. These data suggest that social drinkers who sample alcohol in a laboratory setting can be primed by alcohol to consume more. The results also indicated that the amount drunk was related to the degree to which subjects expected alcohol to increase sociability and to reports of subjective stimulant effects of alcohol (e.g., 'alert', 'clear-headed', 'quick-witted', and 'attentive'). 相似文献
563.
JV Selkirk C Scott M Ho MJ Burton J Watson LM Gaster L Collin BJ Jones DN Middlemiss GW Price 《Canadian Metallurgical Quarterly》1998,125(1):202-208
The vasoactive hormone angiotensin II (Ang II) can stimulate vascular smooth muscle cell (SMC) hypertrophy and proliferation; thus, it may have an important role in the pathogenesis of hypertension, atherosclerosis and restenosis. Several studies have indicated that Ang II bioactivity on SMC may depend, at least in part, on its ability to induce the expression of polypeptide growth factors that can function in an autocrine manner. Here we report that Ang II treatment of rat aortic SMC increases fibroblast growth factor-2 (FGF-2) but not FGF-1 mRNA levels. Increased FGF-2 mRNA expression is first detectable at 30 min after Ang II addition and maximal levels are present at 8 hr. Ang II induction of FGF-2 mRNA levels is dependent on de novo RNA and protein synthesis. The Ang II effect can be blocked by treatment with either the Ang II type 1 receptor-selective antagonist CI-996 or the tyrosine kinase inhibitor genistein. The potent vasoconstrictor and SMC mitogen endothelin-1 can also induce FGF-2 mRNA levels in rat aortic SMC. These results indicate that FGF-2 gene expression is up-regulated by two distinct vasoactive peptides implicated in vascular SMC growth control in vivo. 相似文献
564.
565.
L Cao DL Chen C Lee CM Chan KM Chan N Vanittanakom DN Tsang KY Yuen 《Canadian Metallurgical Quarterly》1998,36(10):3028-3031
The disseminated and progressive fungal disease Penicillium marneffei penicilliosis is one of the most common infectious diseases in AIDS patients in Southeast Asia. To diagnose systemic penicilliosis, we developed an enzyme-linked immunosorbent assay (ELISA)-based antibody test with Mp1p, a purified recombinant antigenic mannoprotein of P. marneffei. Evaluation of the test with guinea pig sera against P. marneffei and other pathogenic fungi indicated that this assay was specific for P. marneffei. Clinical evaluation revealed that high levels of specific antibody were detected in two immunocompetent penicilliosis patients. Furthermore, approximately 80% (14 of 17) of the documented penicilliosis patients with human immunodeficiency virus tested positive for the specific antibody. No false-positive results were found for serum samples from 90 healthy blood donors, 20 patients with typhoid fever, and 55 patients with tuberculosis, indicating a high specificity of the test. Thus, this ELISA-based test for the detection of anti-Mp1p antibody can be of significant value as a diagnostic for penicilliosis. 相似文献
566.
Primase and helicase activities of bacteriophage T7 are present in a single polypeptide coded by gene 4. Because the amino terminal region of the gene 4 protein contributes to primase activity, we constructed a truncated gene 4 encoding the N-terminal 271-aa residues. The truncated protein, purified from cells overexpressing the protein, is a dimer in solution; the full-length protein is a hexamer. Although the fragment is devoid of dTTPase and helicase activities, it catalyzes template-directed synthesis of di-, tri-, and tetranucleotides. The rates for tetraribonucleotide synthesis and for dinucleotide extension on a 20-nucleotide template are similar for the full-length and truncated proteins. However, the activity of the primase fragment is unaffected by dTTP whereas the primase activity of the full-length protein is stimulated >14-fold. The primase fragment is defective in the interaction with T7 DNA polymerase in that primer synthesis cannot be coupled to DNA synthesis. 相似文献
567.
568.
569.
The vitamin-K-dependent serine proteinases of coagulation have evolved by a process of gene duplication and divergence, acquiring along the way a considerable degree of functional diversity that has equipped them for their different roles in haemostasis. The cDNA sequences encoding the catalytic domains of the early mammalian ancestors of five vitamin-K-dependent factors (factors VII, IX and X, protein C and prothrombin) were reconstructed by employing cDNA sequence data from a range of extant mammals and by using established phylogenies. The cDNA sequence of the putative common ancestor of these early mammalian proteins was then reconstructed from the five sequences by using a deduced phylogeny that was different in a number of respects from those previously proposed. Factor IX is proposed to have branched off early on, followed by protein C and prothrombin and finally factors VII and X. Significant differences in mutation rates were observed between proteins within a species; factor IX exhibited a lower mutation rate than the other proteins, consistent with its early emergence. Differences in mutation rates were also observed between species for a given protein and these exhibited an inverse correlation with generation time. A biophysically plausible structure for the ancestral vitamin-K-dependent factor protein was constructed by comparative methods. Studies of the functional architecture of this model provide new insights into the evolution of protein-binding specificity in this family of proteins. 相似文献
570.
Paulo Moreira Vermelho Flávio Henrique Baggio Aguiar André Figueiredo Reis 《The Journal of Adhesion》2013,89(12):1148-1166
This study evaluated the bond strength and ultramorphology of the resin-dentin interfaces produced by current dental adhesive systems. Nine dentin bonding agents were investigated. Restored teeth were vertically, serially sectioned to obtain bonded slices for interfacial TEM analysis or to produce bonded beams for the microtensile bond strength test. The one-step self-etching adhesives (Futurabond® NR and Hybrid Bond®) showed lower bond strength values than the three-step etch-&-rinse adhesive system All-Bond 3. Most bonding agents presented statistically similar mean bond strength values, which ranged from 41.3 ± 17.9 to 35.0 ± 5.3 MPa. The thickness of the hybrid layer varied according to the type of adhesive system used. While the etch and rinse adhesives with alcohol as organic solvent showed bond strength means higher than 40 MPa, the self-etching systems showed bond strength lower than 40 MPa. Resin-dentin interdifusion zone and resin tags were noted in all bonded interfaces. 相似文献