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91.
Interfacial polymerization chemistry has been employed to produce robustly structured supported films of sensor materials. Thin-film materials that incorporate several metalloporphyrins (M = Co(II), Cu(II) and Zn(II)) to use as colorimetric sensors for volatile organic compounds (VOCs) including alcohols, ketones and chlorocarbons have been synthesized. Upon exposure to these VOCs, the sensors’ absorption spectra undergo reversible changes that can be monitored to discriminate amongst analyte species. Sensor sensitivity and selectivity is affected by the metal identity.  相似文献   
92.
The orexin system consists of two G‐protein‐coupled receptors, the orexin 1 and orexin 2 receptors, widely expressed in diverse regions of the brain, and two peptide agonists, orexin A and orexin B, which are produced in a small assembly of neurons in the lateral hypothalamus. The orexin system plays an important role in the maintenance of wakefulness. Several compounds (almorexant, SB‐649868, suvorexant) have been in advanced clinical trials for treating primary insomnia. ACT‐462206 is a new, potent, and selective dual orexin receptor antagonist (DORA) that inhibits the stimulating effects of the orexin peptides at both the orexin 1 and 2 receptors. It decreases wakefulness and increases non‐rapid eye movement (non‐REM) and REM sleep while maintaining natural sleep architectures in rat and dog electroencephalography/electromyography (EEG/EMG) experiments. ACT‐462206 shows anxiolytic‐like properties in rats without affecting cognition and motor function. It is therefore a potential candidate for the treatment of insomnia.  相似文献   
93.
The subset of plasma extracellular vesicles (EVs) that coprecipitate with low-density lipoprotein (LDL-EVs) carry coagulation and fibrinolysis pathway proteins as cargo. We investigated the association between LDL-EV hemostatic/fibrinolysis protein ratios and post-acute myocardial infarction (post-AMI) left ventricular (LV) remodeling which precedes heart failure. Protein concentrations of von Willebrand factor (VWF), SerpinC1 and plasminogen were determined in LDL-EVs extracted from plasma samples obtained at baseline (within 72 h post-AMI), 1 month and 6 months post-AMI from 198 patients. Patients were categorized as exhibiting adverse (n = 98) or reverse (n = 100) LV remodeling based on changes in LV end-systolic volume (increased or decreased ≥15) over a 6-month period. Multiple level longitudinal data analysis with structural equation (ML-SEM) model was used to assess predictive value for LV remodeling independent of baseline differences. At baseline, protein levels of VWF, SerpinC1 and plasminogen in LDL-EVs did not differ between patients with adverse versus reverse LV remodeling. At 1 month post-AMI, protein levels of VWF and SerpinC1 decreased whilst plasminogen increased in patients with adverse LV remodeling. In contrast, VWF and plasminogen decreased whilst SerpinC1 remained unchanged in patients with reverse LV remodeling. Overall, compared with patients with adverse LV remodeling, higher levels of SerpinC1 and VWF but lower levels of plasminogen resulted in higher ratios of VWF:Plasminogen and SerpinC1:Plasminogen at both 1 month and 6 months post-AMI in patients with reverse LV remodeling. More importantly, ratios VWF:Plasminogen (AUC = 0.674) and SerpinC1:Plasminogen (AUC = 0.712) displayed markedly better prognostic power than NT-proBNP (AUC = 0.384), troponin-I (AUC = 0.467) or troponin-T (AUC = 0.389) (p < 0.001) to predict reverse LV remodeling post-AMI. Temporal changes in the ratios of coagulation to fibrinolysis pathway proteins in LDL-EVs outperform current standard plasma biomarkers in predicting post-AMI reverse LV remodeling. Our findings may provide clinical cues to uncover the cellular mechanisms underpinning post-AMI reverse LV remodeling.  相似文献   
94.
Although previous studies have examined characteristics of children selected as friends, little research has examined the role played by characteristics of the selecting child. In 2 experimental studies that examined the role of self-perceptions in peer selection, participants (91 seventh graders in Study 1 and 83 third graders in Study 2) viewed various evaluations of themselves. Participants either believed evaluations were written by unfamiliar peers (Study 1) or were asked to imagine that the views of puppets were views of unfamiliar peers (Study 2). Participants were asked to select the pees they wished to meet and interact with. When evaluations were related to specific competence domains, 7th graders preferred positive peers to negative peers, whereas 3rd graders selected peers who viewed them as they viewed themselves. When evaluations were related to global self-worth, children's selections were unrelated to views of their own global worth. Selection of a globally negative peer was associated with attachment-insecurity/maternal-rejection and depressive symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
95.
Various Brassica species accumulate Se into the thousands of ppm. This suggests some of them as candidates for Se phytoremediation. Brassica juncea (Indian mustard) was used to accumulate selenium by growing with sodium selenite as the selenium source under hydroponic conditions resulting in Se accumulation of up to hundreds of ppm in various parts of the plant. To date, few selenium speciation studies have been done in plants, with most studies reporting total selenium concentration in various parts of the plant. Se species extraction was evaluated by several digestion/extraction procedures, including the use of HCl, Tris-HCl buffer, and enzymatic hydrolysis (using proteinase K and protease XIV). The best extraction was obtained with proteinase K (extracting approximately 75% of the total Se present in the plant). Some of the species produced by the plant, such as selenomethionine, can be identified at ppb levels by RP-HPLC-ICPMS, since standards are readily available. Others needed to be further characterized by ES-MS. Enzymatic hydrolysis releases mostly Se-methionine from juncea leaves, although other Se-containing species can also be observed by HPLC-ICPMS. In this initial study, the possible identification (by ES-MS) of a small chromatographic peak containing a Se-S bridged seleno amino acid with a structure similar to cystine is suggested.  相似文献   
96.
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98.

Scope

Dietary flavan-3-ols are known to mediate cardiovascular benefits. Currently, it is assumed that the levels of flavan-3-ol catabolites detected in humans, 5-(3ʹ,4ʹ-dihydroxyphenyl)-γ-valerolactone (γVL) and 5-(3ʹ,4ʹ-dihydroxyphenyl)-γ-valeric acid (γVA), and their corresponding phase II metabolites, are determined exclusively by the action of the gut microbiome. However, a family of human proteins, paraoxonase (PON), can theoretically hydrolyze γVL metabolites into the corresponding γVAs. This study aims to determine if PON is involved in γVL and γVA metabolism in humans.

Methods and results

A rapid conversion of γVL into γVA is detected in serum ex vivo (half-life = 9.8 ± 0.3 min) that is catalyzed by PON1 and PON3 isoforms. Phase II metabolites of γVL are also reacted with PON in serum. Following an intake of flavan-3-ol in healthy males (n = 13), the profile of γVA metabolites detected is consistent with that predicted from the reactivity of γVL metabolites with PON in serum. Furthermore, common PON polymorphisms are evaluated to assess the use of γVL metabolites as biomarkers of flavan-3-ol intake.

Conclusion

PONs are involved in flavan-3-ol metabolic pathway in humans. PON polymorphisms have a minor contribution to inter-individual differences in the levels of γVL metabolites, without affecting their use as a nutritional biomarker.  相似文献   
99.
This study examined the relation between individual and composite measures of child competence with family background and adult ratings of psychopathology. A battery of psychological tests, generally considered to reflect competent functioning, was administered to 180 children, aged 6–12 years, who were consecutively referred to a psychiatric outpatient clinic. Generally, children who scored high on a composite competence index were rated by parents and teachers as showing fewer problems, which is consistent with observations in nonclinical samples. Moreover, analysis of the composite competence index supported the view that children with even a moderate degree of competence have an advantage. Two findings of this study differed from those observed in nonclinical samples. First, a composite measure of child competence was more likely than single measures to be related to parent and teacher ratings of competence and problems. Second, girls were generally less competent than boys. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
Recently drivers have greatly benefited from new vehicular technologies such as in-car navigation systems, but at the same time they can be easily distracted from those technologies. Consequently, creating displays that balance the communication of information with the attentional demand imposed on the driver is of increasing importance. A set of research has been conducted to minimize the driver’s attentional cost toward the navigational displays while driving. However, accurate evaluation methods to assess the effects of these displays in realistic environments are not yet available. This article introduces the backseat driving technique for high-fidelity, safe, and inexpensive evaluation of interaction with in-car displays. This technique makes use of a real vehicle driving on a real road. As a result it allows for the exploration of some types of research questions using audio, visual, and kinesthetic stimulus at least equal in fidelity to very high-end driving simulators, without requiring such a specialized and expensive facility. Further, it allows for the employment of detailed and fine-grained measures of attentional demand, which cannot be safely used with subjects who are actually driving. Although the backseat driving technique can address only some types of questions and so is not a full replacement for high-realism driving simulators, it may offer a new approach, which augments laboratory, simulator, and real driving for many studies. As a part of the work presented here, the backseat driving technique is used to evaluate a previously developed in-car navigation display—the MOVE system. The technique allowed for new questions to be asked, which were not able to be considered in previous laboratory studies, and for the use of study measures that were only previously able to be used in the laboratory due to driving safety concerns. Specifically, the display was shown to work well when real-world stimulus are used to navigate along a real route, reducing the navigation error rate nearly threefold, and up to sixfold when compared to displays providing more or less contextual information. In addition the display was shown to cut total display fixation time (which is time spent looking away from the road) almost in half in both cases.  相似文献   
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