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11.
Research has suggested that race, gender, and menthol cigarette use influence tobacco-smoke exposure measures and smoking-related disease risk. For example, a high proportion of Black smokers prefer menthol cigarettes and, despite smoking fewer cigarettes per day (CPD) than do Whites, tend to have higher cotinine levels. Additionally, Black males are more at risk for smoking-related lung cancer. High cotinine levels and smoking menthol cigarettes may lead to higher toxin intake, which contributes to increased disease risk. We explored the relationship between tobacco exposure variables (i.e., cotinine, CPD, carbon monoxide [CO], nicotine content, and nicotine dependence) with respect to race, gender, and menthol content in a sample of 307 smokers recruited from the greater Boston area to participate in a smoking cessation treatment trial. The pattern of correlations between tobacco exposure measures and cotinine showed a consistently positive correlation between cotinine and CO in all smokers and a correlation between cotinine and CPD in those who smoked nonmenthol cigarettes. Cotinine and CPD correlations varied by gender and race among menthol cigarette smokers. Consistently, we found a significant gender x race x menthol interaction on salivary cotinine level as well as cotinine/CPD ratio. These findings suggest that the relationship between number of cigarettes consumed and salivary cotinine is more complex than previously believed. It is not sufficient to look at race alone; researchers and clinicians need to look at race and gender concurrently, as well as type of cigarette consumed.  相似文献   
12.
The Port of Kotka is situated by the Baltic Sea and the river Kymi. The river transports into the estuary sediments containing pollutants. The dredging and dumping of the polluted sediments are challenging tasks, which are strictly monitored by the environmental authorities. In this study, we show how a former dumping area was converted into a car storage area in an innovative way. The construction on wetland base was extremely challenging. The field was built by using tyre scrap, which weighs only a quarter of the stone material's weight. The advantage of frost season was used during the construction phase, which reduces the costs. The Port of Kotka's solution to use polluted dredged material and waste material, in order to economically reclaim new land, sets a good example that can be used in other ports as well.  相似文献   
13.
This study provides new knowledge about the factor structure of the 12-item General Health Questionnaire (GHQ-12; D. Goldberg, 1972) through the application of confirmatory factor analysis to longitudinal data, thereby enabling investigation of the factor structure, its invariance across time, and the rank-order stability of the factors. Two community-based longitudinal adult samples with 1-year (n = 640) and 6-year (n = 330) follow-up times were studied. As a result, the correlated 3-factor model (i.e., Anxiety/Depression, Social Dysfunction, and Loss of Confidence) showed a better fit with both samples than the alternative models. The correlated 3-factor structure was also relatively invariant across time in both samples, indicating that the scale has good construct validity. The rank-order stabilities of the factors were low across time, which suggests that the GHQ-12 measures temporal mental state. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
14.
This was the first randomized, controlled smoking cessation trial assessing the efficacy of an exercise intervention as an adjunct to nicotine gum therapy in comparison with both equal contact control and standard care control conditions. Sedentary female smokers aged 18-55 years were provided with nicotine gum treatment along with brief behavioral counseling and were randomized into one of these three behavioral adjunct conditions. In the "intent-to-treat" sample (N = 182), at end of treatment and at 1-year follow-up, there were clear, but nonsignificant, trends in univariate analyses in which the exercise and equal contact control conditions both had higher rates of abstinence than the standard care control. However, when adjusting for other predictors of relapse in a multiple logistic regression, both exercise and equal contact control showed an advantage over standard care control in avoiding early relapse (i.e., after 1 week). In a multivariate survival model adjusting for other predictors, the equal contact condition had a significantly lower likelihood of relapse compared with the standard care condition and there was a near significant trend in which exercise offered an advantage over standard care as well. While these findings suggest a slightly improved likelihood of abstinence with exercise compared with standard care, exercise did not differ from equal contact control in its efficacy. Potential explanations for these equivalent levels of efficacy and implications for the findings are discussed.  相似文献   
15.
Lactoferrin (LF) is an iron-binding glycoprotein exerting several physiological functions such as antimicrobial activity, modulatory effects on lipid metabolism and anti-inflammatory properties. We examined whether LF prevents diet-induced obesity and development of fatty liver formation in C57Bl/6J mice. Lactoferrin (15% of dietary casein replaced by LF) enhanced weight loss and decreased body fat content during energy restriction compared to casein without influencing energy intake. During the ad libitum feeding after weight loss, LF suppressed weight regain and protected against the development of fatty liver formation compared to casein without influencing energy intake or fecal fat excretion. During the weight regain phase LF also improved glucose tolerance, decreased skeletal muscle leptin mRNA expression, and ameliorated adipose tissue inflammation. In conclusion, LF supplementation enhances the outcome of weight loss and subsequent weight regain, ameliorates fatty liver formation, and exerts beneficial effects on glucose tolerance and adipocyte tissue inflammation without interfering energy intake.  相似文献   
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"An experiment was conducted to test the hypothesis that photographs of positively valent faces would be set nearer the subject than negative faces, in ostensibly objective distance judgments… . Several examples of valent faces were compared, e.g., popular vs. unpopular figures from public life, an authority figure vs. peers, and self vs. peers. The responses of women… bore out the predictions, those of the men did not do so uniformly." From Psyc Abstracts 36:04:4GD20B. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
18.
This paper describes the synthesis and characterization of a novel mesostructured solid electrolyte composite material, denoted meso‐SiO2–C12EO10OH–CF3SO3H. A lyotropic non‐ionic surfactant–triflic acid–silicate liquid crystal is used as a supramolecular template for a “one‐pot” synthesis of the material. Within this structure, the oligoethyleneoxide head groups of the non‐ionic surfactant that is imbibed within the channels of hexagonal mesoporous silica act in a crown‐ether‐like fashion towards the protons. The structure and dynamics of the silicate–oligo(ethylene oxide)surfactant–triflic acid co‐assembly has been studied via several analytical techniques. These methods include polarized optical microscopy (POM), powder X‐ray diffraction (PXRD), transmission electron microscopy (TEM), multinuclear nuclear magnetic resonance (NMR) spectroscopy, thermogravimetric analysis (TGA), and Fourier transform (FT) Raman spectroscopy. Together these results imply that the protons coordinate to the oxygen atoms of the ethylene oxide units on the non‐ionic surfactant and the compound has the structural integrity of the silicified liquid crystal. AC impedance spectroscopy was used to determine the proton conductivity of the meso‐SiO2–C12EO10OH–CF3SO3H composite material at different relative humidity values giving some insight into its potential utility as a proton conducting solid electrolyte in a proton‐exchange membrane fuel cell.  相似文献   
19.
The aim of the present study was to improve the quality of fibre-enriched wheat breads by enzymic treatment of the fibre fraction. The suitability of different enzymes in fibre-enriched baking and their effects on the dietary fibre content and the ratio of insoluble: soluble fibre content of the breads were studied. The enzyme preparations used were a hemicellulolytic culture filtrate of Trichoderma reesei, a specific (pI 9) xylanase of T reesei and Fermizyme, an α-amylase preparation containing a standardised level of hemicellulase activity. Rye bran was extracted in water (10% (w/w) suspension) to determine the solubilities of the β-glucans and pentosans. Addition of T reesei culture filtrate significantly increased the amount of extractable pentosan obtained from nonautoclaved rye bran. Rye bran supplementation (5%) of wheat flour increased the farinograph absorption and dough development time, but had little or no effect on stability and softening of the dough. The added enzymes decreased dough stability and increased softening. Addition of enzymes caused significant differences in the stickiness of the wheat doughs both with (P<0·003) and without (P<0·001) rye bran. Fermizyme significantly increased the stickiness of wheat doughs both with and without rye bran. The baking results of the fibre-enriched breads were improved by the added enzymes. Addition of T reesei culture filtrate increased the specific volume of the wheat breads both with and without rye bran by almost 20%. Enzyme mixtures were more efficient than individual xylanase in softening the bread crumb and reducing the staling rate of wheat breads both with and without rye bran. Incorporation of enzymes reduced the total dietary fibre content of the breads, but at least doubled the amount of soluble pentosan. The proportions of fluorescent cell walls in the breads were detected by microscopical image analysis. Enzyme addition caused the surface area of insoluble cell walls originating from wheat flours to decrease, suggesting that the enzymes exert more effects on wheat endorsperm cell walls than on bran particles. © 1998 SCI.  相似文献   
20.
Water-free pure-silica-core fibre has been developed for the first time. It exhibits ultra-low loss of 0.247 dB/km at 1383 nm and 0.170 dB/km at 1550 nm, representing the lowest-loss G.652D fibre. Excellent durability against hydrogen ageing owing to pure-silica-core has also been verified.  相似文献   
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