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61.
肿瘤淋巴管生成是肿瘤转移过程的必要环节,肿瘤细胞可以通过表达淋巴管生成的调控因子VEGF-C和VEGF-D诱导淋巴管生成,并且促进肿瘤细胞的淋巴道转移。肿瘤淋巴管生成及其对抗研究是当前肿瘤研究的热点,并有可能成为治疗肿瘤淋巴道转移的靶点。两者之间关系密切,并且相互作用,相互影响。  相似文献   
62.
Functional analysis suggested that the problem behavior of an 8-year-old girl with autism was maintained by escape from demands and access to edible items. Noncontingent delivery of an edible item was sufficient to increase compliance and reduce the rate of problem behavior without the use of escape extinction in a demand context. Leaner and richer schedules of noncontingent reinforcement were equally effective, and there were minimal differences between noncontingent reinforcement and differential reinforcement of compliance.  相似文献   
63.
This paper presents a systematic approach for obtaining results from the area of quantitative investigations in logic and type theory. We investigate the proportion between tautologies (inhabited types) of a given length n against the number of all formulas (types) of length n. We investigate an asymptotic behavior of this fraction. Furthermore, we characterize the relation between number of premises of implicational formula (type) and the asymptotic probability of finding such formula among the all ones. We also deal with a distribution of these asymptotic probabilities. Using the same approach we also prove that the probability that randomly chosen fourth order type (or type of the order not greater than 4), which admits decidable lambda definability problem, is zero. Presented by Jacek Malinowski  相似文献   
64.
采用两个实验探讨同音字密度对于汉字识别的影响。实验一采用命名任务,结果发现高同音字密度的汉字的加工时间短于低同音字密度的汉字,说明在汉字识别中,同音字密度起促进作用;实验二运用眼动分析的方法,考察在句子阅读中的同音字密度效应。结果发现,读者对高、低同音字密度汉字的加工在各眼动指标上均没有显著差异,说明在正常句子阅读中,同音字密度的效应消失。  相似文献   
65.
Statistics of Intuitionistic versus Classical Logics   总被引:2,自引:1,他引:1  
Kostrzycka  Zofia  Zaionc  Marek 《Studia Logica》2004,76(3):307-328
For the given logical calculus we investigate the proportion of the number of true formulas of a certain length n to the number of all formulas of such length. We are especially interested in asymptotic behavior of this fraction when n tends to infinity. If the limit exists it is represented by a real number between 0 and 1 which we may call the density of truth for the investigated logic. In this paper we apply this approach to the intuitionistic logic of one variable with implication and negation. The result is obtained by reducing the problem to the same one of Dummett's intermediate linear logic of one variable (see [2]). Actually, this paper shows the exact density of intuitionistic logic and demonstrates that it covers a substantial part (more than 93%) of classical prepositional calculus. Despite using strictly mathematical means to solve all discussed problems, this paper in fact, may have a philosophical impact on understanding how much the phenomenon of truth is sporadic or frequent in random mathematics sentences.  相似文献   
66.
This paper introduces a two‐parameter family of distributions for modelling random variables on the (0,1) interval by applying the cumulative distribution function of one ‘parent’ distribution to the quantile function of another. Family members have explicit probability density functions, cumulative distribution functions and quantiles in a location parameter and a dispersion parameter. They capture a wide variety of shapes that the beta and Kumaraswamy distributions cannot. They are amenable to likelihood inference, and enable a wide variety of quantile regression models, with predictors for both the location and dispersion parameters. We demonstrate their applicability to psychological research problems and their utility in modelling real data.  相似文献   
67.
The phonological complexity of dysfluencies in those who clutter and/or stutter may help us better understand phonetic factors in these two types of fluency disorders. In this preliminary investigation, cases were three 14-year-old males, diagnosed as a Stutterer, a Clutterer, and a Stutterer–Clutterer. Spontaneous speech samples were transcribed, coded for dysfluent words which were then matched to fluent words on grammatical class (i.e., function vs. content), number of syllables and word familiarity. An Index of Phonological Complexity was determined per word, and word frequency, density and phonological neighborhood frequency were derived from an online database. Results showed that compared to fluent words, dysfluent words were more phonologically complex and ‘sparser’, implying that they have fewer phonological neighbors or words in which a single phoneme is added, deleted or substituted. Interpretations and future directions for research regarding phonological complexity in stuttering and cluttering are offered.Educational objectives: 1. The reader can list three key symptoms of cluttering. 2. The reader will define phonological neighborhood density and neighborhood frequency. 3. The reader can calculate the Index of Phonological Complexity (IPC) for a given word. 4. The reader can state two findings from the current study and how each relates to other studies of phonological complexity and fluency disorders.  相似文献   
68.
High traffic density may lead to more traffic accidents because of more frequent lane change and overtaking behaviors, but drivers with different characteristics may exhibit different driving behaviors. The present study explored the difference in driving behaviors between drivers with a high/low prosocial attitude under high/low traffic density. In this study, a 2 (high/low prosocial attitude) *2 (high/low traffic density) mixed design was used to investigate the interaction between prosocial attitude and traffic density on lane change and overtaking behavior. The implicit association test paradigm was used to measure prosocial attitude, and drivers were divided into two groups. Forty subjects were asked to complete simulated driving tasks under the two conditions of high and low traffic density, and driving behaviors were recorded by driving simulators. The results show that high traffic density leads to more lane change and overtaking behavior. Drivers with a high prosocial attitude have better driving performance under both high and low traffic density, but drivers with a low prosocial attitude maintain a smaller transverse distance from adjacent vehicles in high traffic density, which may increase risk. This study provides support for the selection, training and intervention of professional drivers.  相似文献   
69.
Language research has come to rely heavily on large-scale, web-based datasets. These datasets can present significant methodological challenges, requiring researchers to make a number of decisions about how they are collected, represented, and analyzed. These decisions often concern long-standing challenges in corpus-based language research, including determining what counts as a word, deciding which words should be analyzed, and matching sets of words across languages. We illustrate these challenges by revisiting “Word lengths are optimized for efficient communication” (Piantadosi, Tily, & Gibson, 2011), which found that word lengths in 11 languages are more strongly correlated with their average predictability (or average information content) than their frequency. Using what we argue to be best practices for large-scale corpus analyses, we find significantly attenuated support for this result and demonstrate that a stronger relationship obtains between word frequency and length for a majority of the languages in the sample. We consider the implications of the results for language research more broadly and provide several recommendations to researchers regarding best practices.  相似文献   
70.
High risk of vulnerable road users (VRUs) injuries and fatalities have received higher interest nowadays in Tunisia. By using VRUs crash record (from January 1, 2001 to December 31, 2013), we describe the spatial pattern of VRUs collisions according to different temporal scales such as (a.m. vs p.m. rush hours VRUs collisions, working days vs non-working days VRUs collisions, daytime vs nighttime VRUs collisions) and investigate the influence of personal and environmental factors for VRUs injuries severity within the Center-East region in Tunisia. The empirical results are of great variety: spatial clustering pattern of each subtype of VRUs collisions according to temporal scale were clearly observed with the exception of daytime VRUs collisions, which shows a random tendency. All time-based subtypes of VRUs collisions also were found to be clustered along the national highways and regional highways especially in the regions of Sousse and Sfax. Results from VRUs severity model suggest that the degree of injury severity is higher for male than for female victim. The Tunisian VRUs are more likely to be involved in severe collision than non-Tunisian VRUs. Among driver contributory factors, the change of direction and hazardous overtaking increase the probability of sustaining fatal accidents compared to other driver contributory factors. The season factor shows that accident severity during the summer season is higher. From a policy view point, this kind of analysis can certainly help Tunisian public authorities to develop appropriate safety measures that can possibly reduce the number of VRUs injuries and fatalities.  相似文献   
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