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131.
结直肠癌是常见的恶性肿瘤,近年来其发病率和病死率都很高,因此做到早发现、早诊断、早治疗很有必要,肿瘤标志物在结直肠癌的诊治中发挥了重要作用,但癌胚抗原等传统肿瘤标志物远远不能满足临床需要,代谢组学的出现解决了这一难题.代谢组学是近年来新发展起来的一门组学技术,随着各种代谢组学分析技术的发展和联用,使其在结直肠癌中有着越来越深入的研究,可用此技术在结直肠癌患者的组织、血液和尿液中寻找差异性代谢产物作为新的肿瘤标志物,在结直肠癌的诊断和治疗上有很大优势.本文将对代谢组学的概况及其在结直肠癌中的研究进展做一综述. 相似文献
132.
Ji Hoon Ryoo 《Multivariate behavioral research》2013,48(4):598-624
Model building or model selection with linear mixed models (LMMs) is complicated by the presence of both fixed effects and random effects. The fixed effects structure and random effects structure are codependent, so selection of one influences the other. Most presentations of LMM in psychology and education are based on a multilevel or hierarchical approach in which the variance-covariance matrix of the random effects is assumed to be positive definite with nonzero values for the variances. When the number of fixed effects and random effects is unknown, the predominant approach to model building is a step-up method in which one starts with a limited model (e.g., few fixed and random intercepts) and then additional fixed effects and random effects are added based on statistical tests. A model building approach that has received less attention in psychology and education is a top-down method. In the top-down method, the initial model has a single random intercept but is loaded with fixed effects (also known as an “overelaborate” model). Based on the overelaborate fixed effects model, the need for additional random effects is determined. There has been little if any examination of the ability of these methods to identify a true population model (i.e., identifying the model that generated the data). The purpose of this article is to examine the performance of the step-up and top-down model building approaches for exploratory longitudinal data analysis. Student achievement data sets from the Chicago longitudinal study serve as the populations in the simulations. 相似文献
133.
Two self-paced reading experiments using a paraphrase decision task paradigm were performed to investigate how sentence complexity contributed to the relative clause (RC) attachment preferences of speakers of different working memory capacities (WMCs). Experiment 1 (English) showed working memory effects on relative clause processing in both offline RC attachment preferences and in online reading time measures, but no effects of syntactic complexity. In Experiment 2 (Korean), syntactic complexity due to greater distance between integrating heads, as measured by the dependency locality theory (Gibson in Cognition 68:1–76, 1998), significantly increased the proportion of attachment to NP1. However, no effects of working memory were found. The difference in results between English and Korean is proposed to be due to head-directionality effects. The results of our study support the conclusion that working memory-based accounts provide a better explanation than previous language-dependent accounts for differences in RC attachment preferences. We propose that previous language dependent-accounts of cross-linguistic differences in RC processing have overlooked the interaction between individual WMC and a language’s general structure, which is a central factor in RC attachment. 相似文献
134.
Denisa Bártková Miroslav Šmíd Bohuslav Mašek Jiří Svoboda 《Philosophical Magazine Letters》2017,97(10):379-385
A nearly abrupt coarsening of grains is observed in a newly developed Fe–Al–O ultra-fine-grained nanocomposite with a significant volume fraction (4%) of alumina nano-precipitates. The microstructure of the alloy was analysed in different states (as-received and annealed) by means of scanning electron microscopy, transmission electron microscopy (TEM) and hardness. The initial grain size 150–200 nm increases up to 50 μm during annealing 1000 °C/8 h and thereafter demonstrates saturation. A linear correlation between volume fraction of coarse grains and hardness was found. It was identified by TEM that alumina nano-precipitates stabilize the dislocation microstructure against recovery very effectively and the grain coarsening is due to fast growth of very few dislocation free grains. Thus, the observed grain coarsening has the attributes of static recrystallization. 相似文献
135.
Literature concerning group ethical decision making in a business setting has traditionally focused on directly comparing group versus individual decisions and then investigating differences. Analysis of the interactive process of group ethical decision making appears sparse. This study addresses the gap by investigating group decision making from a social decision scheme (SDS) perspective in a Chinese cultural setting. A cohort of Chinese accountancy students evaluated ethical business scenarios individually and then in a group context. Group responses could be explained in terms of both the SDS and the Chinese cultural perspective (zhongyong). Specifically, groups did not select the most ethical choice but rather the most moderate of all choices advocated by the majority (zhongyong). These results show the application of SDS theory in a culturally specific (Chinese) environment and note the impact of culturally specific factors (zhongyong) on business decision making. The implications are significant for business. If ethical decisions are entrusted to groups, the impact of culturally specific factors must be fully appreciated in evaluating the final decision. 相似文献
136.
Previous studies have demonstrated that humans have a remarkable capacity to memorise a large number of scenes. The research on memorability has shown that memory performance can be predicted by the content of an image. We explored how remembering an image is affected by the image properties within the context of the reference set, including the extent to which it is different from its neighbours (image-space sparseness) and if it belongs to the same category as its neighbours (uniformity). We used a reference set of 2,048 scenes (64 categories), evaluated pairwise scene similarity using deep features from a pretrained convolutional neural network (CNN), and calculated the image-space sparseness and uniformity for each image. We ran three memory experiments, varying the memory workload with experiment length and colour/greyscale presentation. We measured the sensitivity and criterion value changes as a function of image-space sparseness and uniformity. Across all three experiments, we found separate effects of 1) sparseness on memory sensitivity, and 2) uniformity on the recognition criterion. People better remembered (and correctly rejected) images that were more separated from others. People tended to make more false alarms and fewer miss errors in images from categorically uniform portions of the image-space. We propose that both image-space properties affect human decisions when recognising images. Additionally, we found that colour presentation did not yield better memory performance over grayscale images. 相似文献
137.
Using tournament theory as a guiding theoretical framework, in this study, we assess the organizational implications of pay dispersion and other pay system characteristics on the likelihood of turnover among individual executives in organizational teams. Specifically, we estimate the effect of these pay system characteristics on executive turnover decisions. We use a multi-industry, multilevel data set composed of executives in publicly held firms to assess the effects of pay dispersion at the individual level. Consistent with previous findings, we find that pay dispersion is associated with an increased likelihood of executive turnover. In addition, we find that other pay characteristics also affect turnover, both directly and through a moderating effect on pay dispersion. Turnover is more likely when executives receive lower portions of overall top management team compensation and when they have more pay at risk. These conditions also moderate the relationship between pay dispersion and individual turnover decisions, as does receiving lower compensation relative to the market. 相似文献
138.
Sex Roles - Over the last four decades, as China has transitioned from a socialist centralized economy to a productivity-and-efficiency-oriented market economy, so too have the country’s... 相似文献
139.
Juye Ji Penelope K. Trickett Sonya Negriff 《Journal of psychopathology and behavioral assessment》2010,32(2):203-214
This study investigated the multiple dimensions of self-perception in a sample of sexually abused and nonabused comparison
girls (n = 140), with particular attention to self-perception in the scholastic, social, athletic, physical (appearance), and behavioral
conduct domains. First, this study examined whether the five dimensions of self-perception were psychologically discrete.
Second, the relationships between the self-perception factors and childhood sexual abuse were investigated using structural
equation modeling. The results supported the multidimensionality of self-perception and suggested the presence of two distinct
second-order self-perception factors: academic- and social-self. While the sexually abused girls indicated less positive perception
for the academic-self than the comparison group, the two groups did not differ regarding the social-self. The findings highlight
the importance of a multidimensional approach to self-perception in assessing and treating sexually abused children. 相似文献
140.
消化性溃疡的中医病机为本虚标实,虚、瘀、毒为其最基本的病理特点,治疗应抓住虚、瘀、毒的病理实质,采取健脾和胃补虚、活血通络止痛、解毒导滞和胃的治疗方法,并结合脾胃脏腑的功能特点,灵活运用调达肝木、升清降逆之法以调畅脾胃的功能,从而达到治愈消化性溃疡的目的。 相似文献