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41.
Teodora Barbalata Alina I. Scarlatescu Gabriela M. Sanda Laura Toma Camelia S. Stancu Maria Dorobantu Miruna M. Micheu Anca V. Sima Loredan S. Niculescu 《International journal of molecular sciences》2022,23(17)
Myocardial infarction is one of the leading causes of death worldwide, despite numerous efforts to find efficient prognostic biomarkers and treatment targets. In the present study, we aimed to assess the potential of six microRNAs known to be involved in cardiovascular diseases, cell-free DNA (cfDNA), and mitochondrial DNA (mtDNA) circulating in plasma to be used as prognostic tools for the occurrence of unfavorable outcomes such as major adverse cardiovascular events (MACE) after acute ST-segment elevation myocardial infarction (STEMI). Fifty STEMI patients were enrolled and monitored for 6 months for the occurrence of MACE. Plasma was collected at three time points: upon admission to hospital (T0), at discharge from hospital (T1), and 6 months post-STEMI (T6). Plasma levels of miR-223-3p, miR-142-3p, miR-155-5p, miR-486-5p, miR-125a-5p, and miR-146a-5p, as well as of cfDNA and mtDNA, were measured by RT-qPCR. Results showed that the levels of all measured miRNAs, as well as of cfDNA and mtDNA, were the most increased at T1, compared to the other two time points. In the plasma of STEMI patients with MACE compared to those without MACE, we determined increased levels of miRNAs, cfDNA, and mtDNA at T1. Hence, we used the levels of all measured parameters at T1 for further statistical analysis. Statistical analysis demonstrated that all six miRNAs and cfDNA plus mtDNA levels, respectively, were associated with MACE. The minimal statistical model that could predict MACE in STEMI patients was the combination of mtDNA and miR-142-3p levels, as evidenced by ROC analysis (AUC = 0.97, p < 0.001). In conclusion, the increased plasma levels of mtDNA, along with miR-142-3p, could be used to predict unfavorable outcomes in STEMI patients. 相似文献
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43.
The lipophilic fluorescent probe diphenylhexatriene (DPH) has been shown previously to behave as a marker of plasma membrane in living cell systems, and it is therefore been widely used in membrane fluidity studies via fluorescence anisotropy measurements. The anisotropic coefficient, which is inversely related to the rotational motion of the probe in membrane phospholipids, was significantly higher at 37 degrees C than at 23 degrees C for 9 series of red blood cells ghosts obtained from three healthy subjects. We also have studied the importance of the nature of two different polaroid films which permits the observation of fluorescence polarization. 相似文献
44.
We discuss some relationships between probability theory and statistics on one hand, and the theory of fuzzy sets on the other hand. We develop various statistical techniques for the analysis of imprecise data and for inference based on imprecise data. We study the estimation of fuzzy parameters, testing problems with fuzzy probabilities, and confidence estimation under uncertainty. Finally, we indicate some possible applications to the assessment of credibility in expert systems. 相似文献
45.
Lambertus M. van der Heijdt Fridolin van der Lecq Anand Lachmansingh Kees Versluis Anca van der Kerk-van Hoof Gerrit A. Veldink Johannes F. G. Vliegenthart 《Lipids》1993,28(9):779-782
The aim of this investigation was to determine whether the regioselectivity found for lipoxygenases in the formation of fatty
acid hydroperoxides from linoleic acid is reflected in the formation of dimeric products in secondary reactions involving
linoleic acid, product hydroperoxide and lipoxygenase. A method was therefore developed for the separation and identification
of dimers formed by fusion of two linoleic acid radicals or a linoleic acid radical and linoleate. The method includes solid-phase
extraction, preparative separation of products by thin-layer chromatography, derivatization to the corresponding fully hydrogenated
methyl esters and capillary gas chromatography (GC) coupled with electron impact mass spectrometry. We present evidence that
the formation of octadecadienoate dimers, during the secondary reaction of soybean lipoxygenase-1 or lipoxygenase-3, is a
nonenzymic process that can be envisaged by nonspecific association of intermediate fatty acid radicals (L*) that have dissociated from the enzyme. We could show that the relative amounts of different octadecadienoate dimers formed
remain unaltered, regard-less of pH and type of soybean isoenzyme used. Quantitative analysis by GC showed that under the
reaction conditions used, the formation of dimers branching at the 13-position is preferred. 相似文献
46.
47.
A review of M. Horner's (1968) study and subsequent research using the fantasy-based measure of fear of success suggested the following conclusions: Horner's results do not support the hypothesis that high-fear-of-success females perform poorly under competitive conditions; there are no reliable age or sex differences in motivation to avoid success; fear of success and sex role orientation appear to be unrelated; it is not clear whether the fear-of-success measure taps a motive or taps cultural stereotypes; there are no consistent relationships between fear of success and achievement-related variables; the reliability of the fear-of-success measure is low (probably in the .30-.40 range); and there are no consistent relationships between fear of success and any behavioral measures. It is suggested that future research will have to use new measures of fear of success. 3 such measures and preliminary findings are presented. (43 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
Five experiments examined the effects of attribution, salience, and representativeness of a target person's behavior on consensus bias—the tendency to generalize from the target's behavior to the behavior of the group. Ss were 762 undergraduates. Exp I showed that actors and observers induced to make a situational attribution for a behavior perceived this behavior as more common than did those induced to make a dispositional attribution. Exps II and III showed that observers perceived salient behavior as more common in the group than nonsalient behavior. Exps IV and V showed that observers were more likely to generalize from the behavior of a representative target than from the behavior of a nonrepresentative target. It is concluded that attributes of the target's behavior exercise strong influence on consensus estimates. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
Although long-chain fatty acyl-coenzyme A (LCFA-CoA) thioesters are specific high-affinity ligands for hepatocyte nuclear
factor-4α (HNF-4α) and peroxisome proliferator-activated receptor-α (PPARα), X-ray crystals of the respective purified recombinant
ligand-binding domains (LBD) do not contain LCFA-CoA, but instead exhibit bound LCFA or have lost all ligands during the purification
process, respectively. As shown herein: (i) The acyl chain composition of LCFA bound to recombinant HNF-4α reflected that
of the bacterial LCFA-CoA pool, rather than the bacterial LCFA pool. (ii) Bacteria used to produce the respective HNF-4α and
PPARα contained nearly 100-fold less LCFA-CoA than LCFA. (iii) Under conditions used to crystallize LBD (at least 3 wk at
room temperature in aqueous buffer), 16∶1-CoA was very unstable in buffer alone. (iv) In the presence of the respective nuclear
receptor (i.e., HNF-4α and PPARα), LBD 70–75% of 16∶1-CoA was degraded after 1 d at room temperature in the crystallization
buffer, whereas as much as 94–97% of 16∶1-CoA was degraded by 3 wk. (v) Cytoplasmic LCFA-CoA binding proteins such as acyl-CoA
binding protein, sterol carrier protein-2, and liver-FA binding protein slowed the process of 16∶1-CoA degradation proportional
to their respective affinities for this ligand. Taken together, these data for the first time indicated that the absence of
LCFA-CoA in the crystallized HNF-4α and PPARα was due to the paucity of LCFA-CoA in bacteria as well as to the instability
of LCFA-CoA in aqueous buffers and the conditions used for LBD crystallization. Furthermore, instead of protecting bound LCFA-CoA
from autohydrolysis like several cytoplasmic LCFA-CoA binding proteins, these nuclear receptors facilitated LCFA-CoA degradation. 相似文献
50.
Discusses several methodological, statistical, and interpretative problems in a study of interpersonal stress, facial expressivity, and physiological reactivity conducted by C. I. Notarius et al (see record 1983-05644-001). (2 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献