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1.
In three experiments, the effects of exposure to melodies on their subsequent liking and recognition were explored. In each experiment, the subjects first listened to a set of familiar and unfamiliar melodies in a study phase. In the subsequent test phase, the melodies were repeated, along with a set of distractors matched in familiarity. Half the subjects were required to rate their liking of each melody, and half had to identify the melodies they had heard earlier in the study phase. Repetition of the studied melodies was found to increase liking of the unfamiliar melodies in the affect task and to be best for detection of familiar melodies in the recognition task (Experiments 1, 2, and 3). These memory effects were found to fade at different time delays between study and test in the affect and recognition tasks, with the latter leading to the most persistent effects (Experiment 2). Both study-to-test changes in melody timbre and manipulation of study tasks had a marked impact on recognition and little influence on liking judgments (Experiment 3). Thus, all manipulated variables were found to dissociate the memory effects in the two tasks. The results are consistent with the view that memory effects in the affect and recognition tasks pertain to the implicit and explicit forms of memory, respectively. Part of the results are, however, at variance with the literature on implicit and explicit memory in the auditory domain. Attribution of these differences to the use of musical material is discussed.  相似文献   
2.
Forty-eight heifers (3 mo old) were subjected for 35 wk to twice daily s.c. injections of saline or human somatotropin-releasing factor (5 microgram.kg-1 BW) and photoperiod of 8 h (short day) or 16 h (long day) of light daily according to a 2 X 2 factorial design. There was no treatment effect on slaughter weight, withers height, and carcass length. Somatotropin-releasing factor increased thymus weight, metacarpal length, and protein content of the carcass but decreased carcass fat content. Long day photoperiod increased chest girth, pituitary weight, and carcass yield. Effects of somatotropin-releasing factor and photoperiod were not additive on volume of mammary parenchymal tissue; there was also a treatment interaction on liver and lung weights. However, extraparenchymal mammary tissue was decreased by human somatotropin-releasing factor and short day photoperiod. In conclusion, use of somatotropin-releasing factor and photoperiod treatments affected carcass parameters and composition and mammary growth.  相似文献   
3.
The N terminus of the R1 subunit of herpes simplex virus type 2 ribonucleotide reductase is believed to be a protein kinase domain mainly because the R1 protein was phosphorylated in a protein kinase assay on blot. Using Escherichia coli and adenovirus expression vectors to produce R1, we found that, whereas the reductase activity of both recombinant proteins was similar, efficient phosphorylation of R1 and casein in the presence of Mg2+ was obtained only with the R1 purified from eukaryotic cells. Phosphorylation of this R1, in solution or on blot, results mainly from the activity of casein kinase II (CKII), a co-purifying protein kinase. Labeling on blot occurs from CKII leakage off the membrane and its subsequent high affinity binding to in vivo CKII-phosphorylated R1. CKII target sites were mapped to an acidic serine-rich segment of the R1 N terminus. Improvement in purification of the R1 expressed in eukaryotic cells nearly completely abolished its phosphorylation potential. An extremely low level of phosphorylation observed in the presence of Mn2+ with the R1 produced in E. coli was probably due to an unidentified prokaryotic protein kinase. These results provide evidence that the herpes simplex virus type 2 R1 does not possess an intrinsic protein kinase activity.  相似文献   
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5.
Young Holstein male calves, fitted with re-entrant duodenal fistulae, were fed 25% fat milk replacers containing either butter oil, lard, or corn oil in a 3 X 3 Latin square experiment. Proteins were supplied by skim milk powder. Patterns of changes with time after feeding were observed for the composition and pH of duodenal digesta, recovery rates of fresh and dry matter, rates of abomasum emptying for fresh and dry matter, gastric proteolysis, and diarrhea. The composition and pH of duodenal digesta changed markedly with time after feeding, but the only notable differences between milk replacers were for contents of protein nitrogen and total nitrogen. Recovery rates of fresh matter were higher than 100%, presumably due to salivary and gastric secretions. Dry matter was recovered at a rate averaging 100% suggesting that the method used to measure the flow rate and sample duodenal digesta was adequate. The highest flow rates of fresh matter were during the first 3 h after feeding. Differences were marked among the flow rates of constituents of dry matter. Gastric proteolysis was not influenced by the nature of dietary fats. Fecal dry matter, a measure of the severity of diarrhea, was markedly lower for the milk replacer filled with corn oil than for the other two milk replacers.  相似文献   
6.
Coagulase-negative staphylococci (CNS) are considered to be commensal bacteria in humans and animals, but are now also recognized as etiological agents in several infections, including bovine mastitis. Biofilm formation appears to be an important factor in CNS pathogenicity. Furthermore, some researchers have proposed that CNS colonization of the intramammary environment has a protective effect against other pathogens. The mechanisms behind the protective effect of CNS have yet to be characterized. The aim of this study was to evaluate the effect of CNS isolates with a weak-biofilm phenotype on the biofilm formation of other staphylococcal isolates. We selected 10 CNS with a weak-biofilm phenotype and 30 staphylococcal isolates with a strong-biofilm phenotype for this study. We measured biofilm production by individual isolates using a standard polystyrene microtiter plate assay and compared the findings with biofilm produced in mixed cultures. We confirmed the results using confocal microscopy and a microfluidic system with low shear force. Four of the CNS isolates with a weak-biofilm phenotype (Staphylococcus chromogenes C and E and Staphylococcus simulans F and H) significantly reduced biofilm formation in approximately 80% of the staphylococcal species tested, including coagulase-positive Staphylococcus aureus. The 4 Staph. chromogenes and Staph. simulans isolates were also able to disperse pre-established biofilms, but to a lesser extent. We also performed a deferred antagonism assay and recorded the number of colony-forming units in the mixed-biofilm assays on differential or selective agar plates. Overall, CNS with a weak-biofilm phenotype did not inhibit the growth of isolates with a strong-biofilm phenotype. These results suggest that some CNS isolates can negatively affect the ability of other staphylococcal isolates and species to form biofilms via a mechanism that does not involve growth inhibition.  相似文献   
7.
Eighteen multiparous Holstein cows in the second half of their lactation were used to determine the effect of human growth hormone-releasing factor (1-44)NH2 and a fragment of growth hormone-releasing factor (1-29)NH2 on lactational performance and feed intake. Saline, the 44-amino acid peptide or the 29-amino acid fragment, at the same dose per injection (.2 nmol.kg-1) was injected intravenously at 4-h intervals for 10 d. Average milk yield, milk composition, feed intake, and feed efficiency were compared for the second half of each 10-d preinjection, injection, and post-injection period. Injections of the 44-amino acid peptide and the 29-amino acid fragment increased milk yield 18.6 and 14.6%, respectively. Feed intake was not changed, but feed efficiency was increased 23.9 and 18.8% over control following 44-amino acid peptide and the 29-amino acid fragment injection, respectively. The lactational response was not different between the two peptides for any of the variables measured. This study demonstrates the feasibility of using a growth hormone-releasing factor fragment as an alternative method of elevating milk yield in cattle via somatotropins.  相似文献   
8.
The main goal of this study was to examine an integrative model in which academic motivation was hypothesized to mediate the relationships between dispositional optimism and pessimism and coping utilization during the preparation for midterm exams. A sample of 299 undergraduate students completed measures of optimism and academic motivation two weeks prior to midterm exams and measures of academic motivation and coping two weeks after midterm exams. Results of structural equation modeling indicated that self-determined motivation mediated the relationship between dispositional optimism and task-oriented coping, whereas non-self-determined motivation mediated the relationship between dispositional pessimism and disengagement-oriented coping. Furthermore, task-oriented coping was associated with an increase in self-determined motivation from Time 1 to Time 2, whereas disengagement-oriented coping related to an increase in non-self-determined motivation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
The aim of this study was to investigate the influence of food odorant names on feelings through the verbal measurement of emotions. Two experiments were conducted. In the first experiment, 88 participants were asked to report their feelings about 17 food odorants, randomly presented in six sensory booth sessions and in three conditions. In two conditions, an actual odorant was presented blind or in association with its name. In a third condition, only the odorant name was presented. Feeling measurements were conducted by using the ScentMoveTM questionnaire (Porcherot et al., 2010). Participants also rated the familiarity, acceptability, and typicality of the odorants. Results indicated that the odorant name information may influence the reported feelings, as already observed by several authors for traditional liking assessments, with differences among feeling dimensions and odorants. The odorants could be gathered into four groups, with either matches between expected feelings from the odorant name and experienced feelings from the smell evaluation for eight odorants (e.g., caramel, citrus, and mint), or discrepancies between expected and experience feelings for nine odorants, and with no effect of the odorant name information (e.g., strawberry, vanilla), few, or high positive effects of the odorant name information (e.g., cola, chicken). Typicality scores did not differ between the different groups, showing that higher odorant typicality would not systematically result in a match between expectation and experience, or in a positive effect of the name information. It was therefore investigated in a second experiment if the group constitution could be explained by the odorant recognition scores that were measured from a free recognition task for the 17 odorants presented in the blind condition. The results of the two experiments are discussed in relation to dissimilarities between smell and food experiences and to lack of context.  相似文献   
10.
Polychlorinated biphenyls (PCBs) are ubiquitously present in the environment and suspected of carcinogenic, neurological, and immunological effects. Our purpose was to identify predictors of adipose tissue levels of mono-, di-, and tri-ortho-substituted PCBs experienced by a general population and to establish whether predictors vary according to substitution group. In this study of 245 randomly selected persons from a prospective Danish cohort of 57,053 persons, we examined geographical area, age, lactation, BMI, and intake of eight major dietary groups as potential determinants of adipose concentrations of mono-, di-, and tri-ortho-substituted PCBs by linear regression analyses. Lactation, BMI, and intake of fruit, vegetables, and dairy products showed negative associations with PCB concentrations in adipose tissue in all models, and living in Copenhagen city, age, and consumption of fish (particularly fatty fish) were positively associated. The associations between several of the predictors and mono-ortho-substituted PCBs tended to differ from the associations found for di- and tri-ortho-substituted PCBs. In conclusion, geography, age, lactation, BMI, and consumption of fatty fish consistently predicted the concentration of PCBs in adipose tissue. Our results indicate that predictors of PCBs varied according to substitution group, suggesting that ortho-substituted groups should be analyzed separately.  相似文献   
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