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31.
A survey of all PhD programs in psychology in the US and Canada assessed the extent to which advances in statistics, measurement, and methodology have been incorporated into doctoral training. In all, 84% of the 222 departments responded. The statistical and methodological curriculum has advanced little in 20 yrs; measurement has experienced a substantial decline. Typical 1st-yr courses serve well only those students who undertake traditional laboratory research. Training in top-ranked schools differs little from that in other schools. New PhDs are judged to be competent to handle traditional techniques, but not newer and often more useful procedures, in their own research. Proposed remedies for these deficiencies include revamping the basic required quantitative and methodological curriculum, culling available training opportunities across campus, and training students in more informal settings, along with providing retraining opportunities for faculty. These strategies require attention to the human capital needs that support high-quality quantitative and methodological training and practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A multicomponent intervention to increase condom use in sexually active young women was designed, implemented, and evaluated in a randomized experiment. Participants were 198 unmarried female college students (mean age = 18.6 years) who received a 1-session condom promotion intervention or a control (stress management) intervention. The condom promotion intervention led to increased self-reported condom use up to 6 months following intervention as well as positive changes in perceived benefits of condom use, affective attitudes toward condom use and condom users, perceived acceptance of sexuality, control over the sexual encounter, perceived self-efficacy for condom use, and intentions to use condoms. Mediational analysis illustrated the mechanisms of the condom promotion intervention effects, linking psychological constructs affected by the intervention (perceived benefits, acceptance of sexuality, control over the sexual encounter, attitudes toward condoms, and self-efficacy for condom use) to condom use intentions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Atmospheric aerosol samples were collected during different prevailing wind directions from a site located close to a busy motorway, a major steelworks, and the town of Port Talbot (Wales, UK). A high-volume collector was used (1100 l/min), enabling relatively large amounts of particulate matter (PM(10-2.5) and PM(2.5)) samples to be obtained on a polyurethane foam [PUF, H(2)N-C(O)O-CH(2)CH(3)] substrate over periods of 2-7 days. Four samples were chosen to exemplify different particle mixtures: SE- and NE-derived samples for particles moving along and across the motorway, a NW-derived sample from the town, and a mixed SW/SE-derived sample containing a mixture of particles from both steelworks and motorway. The latter sample showed the highest average collection rate (0.9 mg/h, 13 microg/m(3)) and included a prominent pollution episode when rainy winds were blowing from the direction of the steelworks. Both NW and SE samples were collected under dry conditions and show the same collection rate (0.7 mg/h, 10 microg/m(3)), whereas the NE sample was collected during wetter weather and shows the lowest rate (0.3 mg/h, 5 microg/m(3)). Scanning electron microscopy (SEM) and energy-dispersive X-ray microanalysis system (EDX) analyses show all samples are dominated by elemental and organic carbon compounds (EOCC) and nitrates, with lesser amounts of sulphates, felsic silicates, chlorides and metals. ICP-MS analyses show the SW/SE sample to be richest in metals, especially Fe, Zn, Ni, and Mn, these being attributed to an origin from the steelworks. The SE sample, blown along the motorway corridor, shows enhanced levels of Pb, V, Ti, As, and Ce, these metals being interpreted as defining a traffic-related chemical fingerprint. The NW sample shows a very low metal content. DNA plasmid assay data on the samples show TM(50) values varying from 66 to 175 microg/ml for the adjusted whole sample and 89 to 203 microg/ml for the soluble fraction. The SW/SE-mixed metalliferous sample is the most bioreactive (both whole and soluble) and the soluble fraction of the metal-depleted NW sample is the least bioreactive. The metal content of the aerosol samples, especially soluble metals such as Zn, is suggested to be the primary component responsible for oxidative damage of the DNA, and therefore most implicated in any health effects arising from the inhalation of these particulate cocktails.  相似文献   
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Chronic liver disease is generally widespread, and a test for screening fibrotic subjects in a large population is needed. The ability of Wisteria floribunda agglutinin-positive mac-2 binding protein (WFA+-M2BP) to detect significant fibrosis was investigated in health checkup subjects in this research. Of 2021 health checkup subjects enrolled in this prospective cross-sectional study, those with WFA+-M2BP ≥ 1.0 were defined as high risk. Liver fibrosis was evaluated using magnetic resonance elastography (MRE) in subjects with high risk. The primary outcome was the positive predictive value (PPV) of WFA+-M2BP for significant fibrosis (liver stiffness ≥ 2.97 kPa by MRE). This trial was registered with the UMIN clinical trial registry, UMIN000036175. WFA+-M2BP ≥ 1.0 was observed in 5.3% of the 2021 subjects. The PPV for significant fibrosis with the threshold of WFA+-M2BP at ≥1.0, ≥1.1, ≥1.2, ≥1.3, ≥1.4, and ≥1.5 was 29.2%, 36.4%, 43.5%, 42.9%, 62.5%, and 71.4%, respectively. A WFA+-M2BP of 1.2 was selected as the optimal threshold for significant fibrosis among high-risk subjects, and the PPV, negative predictive value, sensitivity, and specificity for significant fibrosis were 43.5%, 84.0%, 71.4%, and 61.8%, respectively. WFA+-M2BP ≥ 1.2 was significantly associated with significant fibrosis, with an odds ratio (OR) of 4.04 (95% confidence interval (CI): 1.1–16, p = 0.04), but not FIB-4 ≥ 2.67 (OR: 2.40, 95%CI: 0.7–8.6, p-value = 0.2). In conclusion, WFA+-M2BP is associated with significant fibrosis and could narrow down potential subjects with liver fibrosis. The strategy of narrowing down fibrosis subjects using WFA+-M2BP may be used to screen for fibrotic subjects in a large population.  相似文献   
36.
Altogether 114 samples of alcoholic and non‐alcoholic bottled beer produced in 28 breweries in the Czech Republic were monitored for levels of biogenic amines (BA) and polyamines (PA). The beers were analysed immediately after purchase and then at the end of the best‐before period (storage temperature 8 ± 1 °C). The concentrations of histamine, phenylethylamine and tryptamine in the studied samples were very low (mostly under 30 mg L?1). The studied PA spermine and spermidine also occurred in small amounts. Nevertheless, the levels of tyramine, putrescine and cadaverine reached significant values, especially in alcoholic beers. In almost 25% of the tested samples of alcoholic beers (at the end of the best‐before period), the total amount of all the monitored BA and PA exceeded the ‘healthy’ level of 100 mg L?1, which is considered toxicologically significant, especially in alcoholic beverages. Copyright © 2012 The Institute of Brewing & Distilling  相似文献   
37.
The effect of elevated temperature on ripening of Dutch type cheese   总被引:1,自引:0,他引:1  
The aim of this study was to explore the effect of elevated temperature (16 °C) on ripening of Dutch-type cheese. Three slices of each cheese block were further divided into three layers. The processes in the control samples of cheese ripening at 10 °C were also monitored. The contents of free amino acids in accelerated cheese were two times higher than were those in control samples. The highest contents of free amino acids were observed in the cores of all slices of cheeses ripening at both temperatures. The contents of tyramine, in layers of the studied slices, reached almost 500 mg kg−1 during 56 days of the experiment. The contents of biogenic amines in the edges grew even higher. Accelerated cheese showed faster equalisation of hardness than did control samples. The increase of temperature by 6 °C can reduce the ripening time in cellars by approximately one half.  相似文献   
38.
Confirmatory factor analysis was used to explore a 3-factor model of expressed emotion (Criticism, Emotional Overinvolvement, and Positivity) in a sample of 104 outpatients with agoraphobia or obsessive-compulsive disorder and 104 relatives of these patients. Multiple methods of measurement included the Camberwell Family Interview, observation of verbal and nonverbal behaviors during patient–relative problem-solving interactions, and ratings of relatives' behavior made by patients and by relatives. The convergent validity of the 3 individual constructs was demonstrated through single-factor models fitted to Criticism, Positivity, and Emotional Overinvolvement measures. A 3-factor model was then estimated and determined to provide adequate fit to the data, thus demonstrating the distinctiveness of the constructs. Criticism and Positivity were strongly and negatively correlated, whereas Emotional Overinvolvement bore little relationship to the other 2 factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
39.
Biogenic amines (BAs) represent a considerable toxicological risk in some food products. Putrescine is one of the most common BAs in food. Its increased occurrence in food may lead to alimentary poisoning, due to enhancement of the toxic effects of other BAs, and also to lower quality of food, this amine is potentially carcinogenic. Increased occurrence of putrescine in food is mainly due to the bacterial metabolism of the Gram‐negative as well as Gram‐positive bacteria present. The bacterial metabolism of putrescine is very specific due to its complexity (in comparison with the metabolism of other BAs). There are 3 distinct known pathways leading toward the formation of putrescine, in some splices involving up to 6 different enzymes. The existence of more metabolic pathways and the possibility of their simultaneous use by different bacteria complicate the specification of the best conditions for food production and storage, which could lead to a lower content of putrescine. This review provides a summary of the existing knowledge about putrescine production and detection (mainly detection of specific genes for different enzymes using polymerase chain reaction) in both starter and contaminating microorganisms. Thus, this comprehensive review gives a useful overview for further research.  相似文献   
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