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231.
Developed tools to quantify and examine the Color-Your-Life (CYL) technique. Two hurdles were overcome in researching the CYL: (1) standardizing administration and (2) quantifying the drawings. 173 ethnically diverse children, aged 6–13 yrs, were instructed to name various emotions until 8 different emotions were written on the blackboard. A piece of paper with the names of 8 standard crayon colors was handed to each S. Ss then paired an emotion from the board with the color they associated it with on the paper. Findings show some ethnic differences in the pairings. Based on the results the following color-affect pairings were selected: RED-mad, ORANGE-excited, YELLOW-happy, GREEN-lonely, BLUE-sad, BROWN-bored, BLACK-scared, and PURPLE-choice. Standard instructions for giving the CYL were developed and inter-rater reliability was found to be 99.5%. A quantification system was devised using computer graphics which allowed for the measurement of percent of color. A brief report on a pilot study of the use CYL in 80 normal Ss, aged 6–12 yrs, revealed age, gender, and ethnic group differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
232.
Natural dentitions of elderly people are often reduced and the remaining teeth are heavily restored. It is unknown whether they are satisfied or dissatisfied with this situation. To get more insight into this phenomenon 320 dentate non-institutionalized elderly subjects were clinically examined and interviewed by means of a questionnaire. Analysis of the data showed that only 13% of the subjects had at least a complete dentition from the right first molar to the left first molar; 50% had less than four occlusal units, 39% of the subjects were wearing a removable partial denture. Ninety per cent of the subjects was satisfied with the dental state and nearly all subjects mentioned they could chew well (97%), despite the fact that 91% of the subjects mentioned they had to deal with one or more dental discomforts. Satisfaction decreased significantly when the number of the occlusal units was reduced or a removable partial denture was present. The conclusion is drawn that although the dentitions of the elderly are often reduced they are, in general, satisfied with their dental state.  相似文献   
233.
A modulation scheme for varying the data rate and transmitted power in accordance with received signal strengths in a fading channel is discussed. The system, using ideal feedback, performs better than one using only rate control with the same constraint on bandwidth.  相似文献   
234.
Although courts have increasingly required that adolescent defendants be competent to proceed with adjudication, the legal standard for competence in juvenile court is not yet settled. As a first step toward obtaining greater clarification in legal standards, in this study the authors surveyed 338 judges and defense attorneys regarding their beliefs about competence standards. Judges and defense attorneys believe that it is particularly important for juveniles to have competence-related legal capacities, compared to adults. However, lower levels of competence were considered necessary for juveniles adjudicated in juvenile court than for juveniles adjudicated in criminal court. Developmental immaturity was seen as moderately important to juveniles' competence, although it was rated as less important than mental disorders or cognitive impairments. Furthermore, relatively few judges appear to agree that adolescents should be found incompetent on the basis of developmental immaturity alone. The implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
235.
Although sleep disturbances in children are common, little is known about the relationship between children's sleep disruptions and maternal sleep and daytime functioning. Forty-seven mothers completed measures of sleep, depression, parenting stress, fatigue, and sleepiness. Significant differences in maternal mood and parenting stress were found between mothers of children with and without significant sleep disturbances. Regression analyses showed that the quality of the children's sleep significantly predicted the quality of maternal sleep. In addition, maternal sleep quality was a significant predictor of maternal mood, stress, and fatigue. Results from this pilot study support the need for future research examining the relationship between child sleep disturbances and maternal daytime functioning, and they highlight the importance of screening for and treating pediatric sleep disruptions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
236.
Mammalian females are endowed with a finite number of primordial follicles at birth or shortly thereafter. Immediately following the formation of the primordial follicle pool, cohorts of these follicles are recruited to begin growth, and this recruitment continues until the primordial follicle population is depleted. Once recruited, a follicle will either grow and ovulate or undergo atresia. Follicle atresia results from the apoptotic death of follicular cells. Members of the BCL-2 family of proteins are important regulators of apoptosis in most cells including in the ovary. Here, we tested the hypothesis that the proapoptotic BAX is an important regulator of follicle survival. We used a variety of histological and biochemical techniques to investigate the impact of Bax deletion on follicle growth and death. We observed that the Bax deletion results in delayed vaginal opening and altered follicular growth. Young adult Bax-deficient ovaries contained increased numbers of primordial follicles and a trend towards reduced numbers of growing follicles. Bax deficiency led to a reduction in average litter size, and also a reduction in the number of oocytes ovulated in response to exogenous gonadotropins. In contrast, Bax deficiency did not alter follicle atresia. In conclusion, BAX appears to be an important regulator of follicle growth, but is dispensable for follicle atresia in mice.  相似文献   
237.
Protein-based biopharmaceuticals are becoming increasingly widely used as therapeutic agents, and the characterization of these biopharmaceuticals poses a significant analytical challenge. In particular, monitoring posttranslational modifications (PTMs), such as glycosylation, is an important aspect of this characterization because these glycans can strongly affect the stability, immunogenicity, and pharmacokinetics of these biotherapeutic drugs. Raman spectroscopy is a powerful tool, with many emerging applications in the bioprocessing arena. Although the technique has a relatively rich history in protein science, only recently has Raman spectroscopy been investigated for assessing posttranslational modifications, including phosphorylation, acetylation, trimethylation, and ubiquitination. In this investigation, we develop for the first time Raman spectroscopy combined with multivariate data analyses, including principal components analysis and partial least-squares regression, for the determination of the glycosylation status of proteins and quantifying the relative concentrations of the native ribonuclease (RNase) A protein and RNase B glycoprotein within mixtures.  相似文献   
238.
The budding yeast, Saccharomyces cerevisiae, responds to changes in external osmolarity through the activation of an osmosensing signal transduction pathway. Using lacZ-reporter gene fusions, clonal cell lines were screened for levels of beta-galactosidase activity in the presence or absence of osmotic stress. A screen of 9,000 transformants displayed 663 (7%) gene fusions that were active in rich medium. Each of the transformants were also assayed for gene activity 24 h following a transfer to high osmolarity medium (0.6 M NaCl) and of the 9,000 clonal cell lines, 86 (1%) displayed a decrease in expression, and seven (0.1%) displayed a reproducible increase in gene expression during primary screening. The chromosomal loci of the lacZ insertions were determined, and the gene(s) associated with that site was examined for osmotically induced expression using RNA blot analysis. Five stress-activated genes were analysed by RNA blot: YDL222C, NMD2, PTC7, FAA4 and YRF1. The genes identified by this screen encompass cellular adaptations to stress including signal transduction, protein myristoylation and fatty acid/sphingolipid content in the cell membrane.  相似文献   
239.
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   
240.
Many alternatives to human donor corneas are being developed to meet the global shortage of donated tissues. However, corneal transplantation remains the gold standard for diseases resulting in thinning corneas. In this study, transparent low energy photoactivated extracellular matrix-mimicking materials are developed for intrastromal injection to restore stromal thickness. The injectable biomaterials are comprised of short peptides and glycosaminoglycans (chondroitin, hyaluronic acid) that assemble into a hydrogel when pulsed with low-energy blue light. The dosage of pulsed-blue light needed for material activation is minimal at 8.5 mW cm−2, thus circumventing any blue light cytotoxicity. Intrastromal injection of these light-activated biomaterials in rat corneas shows that two iterations of the formulations remain stable in situ without stimulating significant inflammation or neovascularization. The use of low light intensities and the ability of the developed materials to stably rebuild and change the curvature of the cornea tissue make these formulations attractive for clinical translation.  相似文献   
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