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1.
Sign language studies of cross-fostered chimpanzees measure the effect of special rearing conditions on the development of very young chimpanzees. Cross-fostered chimpanzees, like human children, develop gradually in a process that takes many years. Here we discuss details of the procedure, the overlap between human and chimpanzee infants in the contents of the first 50-item vocabularies, and the ways in which the signs of the chimpanzees exhibit the fuzziness of natural language categories. We also compare the cross-fostering approach with more traditional modular approaches to the study of language-like behavior in nonhuman animals. Project Washoe was originally supported by grants MH-12154 from the National Institute of Mental Health and GB-7432 from the National Science Foundation. We gratefully acknowledge this support and the support that later sign language studies of chimpanzees have received since then from NIH, NSF, the National Geographic Society, the Grant Foundation, the Spencer Foundation, the University of Nevada, and the UNR Foundation.  相似文献   
2.
ObjectivesBrain neoplasms or intracranial tumors, which are more common in older adults, can affect individuals of any age including pediatric and children. Exposure to carcinogenic agents including ionizing radiation and family history is one of the main causes of the disease. Early diagnosis is crucial to avoid prolonged. patients' suffering. The aim of the study was to efficiently recognize the brain tumors from the other brain tissues which include grey and white matter as well as cerebrospinal fluid (CSF).Materials and methodsThis study was performed using axial, sagittal and coronal views for fifty brain tumor patients randomly selected from a set of 200 patients, with a “control” set consisting of images showing no sign of disease; and the “test” brain MRI images for patients diagnosed with brain tumor. The study includes both genders with age ranging from 18 years to 83 years old, (56.5 ± 17.2). The brain images were acquired using a standard head coil Philips Intera 1.5 Tesla machine (USA). The thickness of each section in the entire sequence was 8 mm. Acquisition of T2-weighted and T1-weighted were performed. Interactive Data Language software was used to analyze the data.ResultsThe results of this study showed that: the overall accuracy of classification process was 94.8%, and for the tumor; the sensitivity was 97.3%. White matter and grey matter showed a classification accuracy of 95.7% and 89.7% and for CSF the accuracy was 94.3%.ConclusionThe results showed that brain tumor can be classified successfully and delineated using texture analysis with minimum efforts and with high accuracy for brain tumors.  相似文献   
3.
Bioinformatics tools have facilitated the reconstruction and analysis of cellular metabolism of various organisms based on information encoded in their genomes. Characterization of cellular metabolism is useful to understand the phenotypic capabilities of these organisms. It has been done quantitatively through the analysis of pathway operations. There are several in silico approaches for analyzing metabolic networks, including structural and stoichiometric analysis, metabolic flux analysis, metabolic control analysis, and several kinetic modeling based analyses. They can serve as a virtual laboratory to give insights into basic principles of cellular functions. This article summarizes the progress and advances in software and algorithm development for metabolic network analysis, along with their applications relevant to cellular physiology, and metabolic engineering with an emphasis on microbial strain optimization. Moreover, it provides a detailed comparative analysis of existing approaches under different categories.  相似文献   
4.
The master circadian pacemaker emits signals that trigger organ-specific oscillators and, therefore, constitutes a basic biological process that enables organisms to anticipate daily environmental changes by adjusting behavior, physiology, and gene regulation. Although circadian rhythms are well characterized on a physiological level, little is known about circadian modulations of higher cognitive functions. Thus, we investigated circadian repercussions on language performance at the level of minimal syntactic processing by means of German noun phrases in ten young healthy men under the unmasking conditions of a 40 h constant-routine protocol. Language performance for both congruent and incongruent noun phrases displayed a clear diurnal rhythm with a peak performance decrement during the biological night. The nadirs, however, differed such that worst syntactic processing of incongruent noun phrases occurred 3 h earlier (07:00 h) than that of congruent noun phrases (10:00 h). Our results indicate that language performance displays an internally generated circadian rhythmicity with optimal time for parsing language between 3 to 6 h after the habitual wake time, which usually corresponds to 10:00–13:00 h. These results may have important ramifications for establishing optimal times for shiftwork changes or testing linguistically impaired people.  相似文献   
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6.
目的:探讨体外反搏联合言语训练治疗脑性瘫痪并语言发育迟缓儿童的临床疗效。方法:选择2015年12月至2017年12月在上海市儿童医院康复科普通门诊确诊的脑瘫并语言发育迟缓患儿52例,按照随机数字表法将其随机分为治疗组和对照组,每组26例。对照组仅给予言语训练治疗,治疗组给予体外反搏联合言语训练治,以4周1个疗程,两组均治疗3个疗程。治疗前后,采用中国康复研究中心汉语版儿童语言发育评定法s-s法、Gesell发育评分法评价和比较患儿言语发育商和认知发育商的变化。结果:治疗后,两组言语发育商和认知发育商均显著高于治疗前,且治疗组言语发育商和认知发育商均显著高于对照组,差异均有统计学意义(均P0.01)。结论:体外反搏联合言语训练较单纯言语训练可更有效改善脑瘫并语言发育迟缓患儿的言语发育和认知发育。  相似文献   
7.
Human language is unique among the communication systems of the natural world. The vocabulary of human language is unique in being both culturally transmitted and symbolic. In this paper I present an investigation into the factors involved in the evolution of such vocabulary systems. I investigate both the cultural evolution of vocabulary systems and the biological evolution of learning rules for vocabulary acquisition. Firstly, vocabularies are shown to evolve on a cultural time-scale so as to fit the expectations of learners-a population's vocabulary adapts to the biases of the learners in that population. A learning bias in favour of one-to-one mappings between meanings and words leads to the cultural evolution of communicatively optimal vocabulary systems, even in the absence of any explicit pressure for communication. Furthermore, the pressure to conform to the biases of learners is shown to outweigh natural selection acting on cultural transmission. Human language learners appear to bring a one-to-one bias to the acquisition of vocabulary systems. The functionality of human vocabulary may therefore be a consequence of the biases of human language learners. Secondly, the evolutionary stability of genetically transmitted vocabulary learning biases is investigated using both static and dynamic models. A one-to-one learning bias, which leads to the cultural evolution of optimal communication, is shown to be evolutionarily stable. However, the evolution de novo of this bias is complicated by the cumulative nature of the cultural evolution of vocabulary systems. This suggests that the biases of human language learners may not have evolved specifically and exclusively for the acquisition of communicatively functional vocabulary.  相似文献   
8.
The human ventral premotor cortex overlaps, at least in part, with Broca's region in the dominant cerebral hemisphere, that is known to mediate the production of language and contributes to language comprehension. This region is constituted of Brodmann's areas 44 and 45 in the inferior frontal gyrus. We summarize the evidence that the motor related part of Broca's region is localized in the opercular portion of the inferior frontal cortex, mainly in area 44 of Brodmann. According to our own data, there seems to be a homology between Brodmann area 44 in humans and the monkey area F5. The non-language related motor functions of Broca's region comprise complex hand movements, associative sensorimotor learning and sensorimotor integration. Brodmann's area 44 is also a part of a specialized parieto-premotor network and interacts significantly with the neighbouring premotor areas. In the ventral premotor area F5 of monkeys, the so called mirror neurons have been found which discharge both when the animal performs a goal-directed hand action and when it observes another individual performing the same or a similar action. More recently, in the same area mirror neurons responding not only to the observation of mouth actions, but also to sounds characteristic to actions have been found. In humans, through an fMRI study, it has been shown that the observation of actions performed with the hand, the mouth and the foot leads to the activation of different sectors of Broca's area and premotor cortex, according to the effector involved in the observed action, following a somatotopic pattern which resembles the classical motor cortex homunculus. On the other hand the evidence is growing that human ventral premotor cortex, especially Brodmann's area 44, is involved in polymodal action processing. These results strongly support the existence of an execution-observation matching system (mirror neuron system). It has been proposed that this system is involved in polymodal action recognition and might represent a precursor of language processing. Experimental evidence in favour of this hypothesis both in the monkey and humans is shortly reviewed.  相似文献   
9.
Xiao Y  Xu C  Xu L  Guan J  Ping Y  Fan H  Li Y  Zhao H  Li X 《Gene》2012,499(2):332-338
The development of heart failure (HF) is a complex process that can be initiated by multiple etiologies. Identifying common functional modules associated with HF is a challenging task. Here, we developed a systems method to identify these common functional modules by integrating multiple expression profiles, protein interactions from four species, gene function annotations, and text information. We identified 1439 consistently differentially expressed genes (CDEGs) across HF with different etiologies by applying three meta-analysis methods to multiple HF-related expression profiles. Using a weighted human interaction network constructed by combining interaction data from multiple species, we extracted 60 candidate CDEG modules. We further evaluated the functional relevance of each module by using expression, interaction network, functional annotations, and text information together. Finally, five functional modules with significant biological relevance were identified. We found that almost half of the genes in these modules are hubs in the weighted network, and that these modules can accurately classify HF patients from healthy subjects. We also identified many significantly enriched biological processes that contribute to the pathophysiology of HF, including two new ones, RNA splicing and vesicle-mediated protein transport. In summary, we proposed a novel framework to analyze common functional modules related to HF with different etiologies. Our findings provide important insights into the complex mechanism of HF. Further biological experimentations should be required to validate these novel biological processes.  相似文献   
10.
The one-third law of evolutionary dynamics [Nowak et al. 2004. Emergence of cooperation and evolutionary stability in finite populations. Nature 428, 246-650] describes a robustness criterion for evolution in a finite population: If at an A-frequency of 1/3, the fitness of an A player is greater (smaller) than the fitness of a B player, then a single A mutant that appears in a population of otherwise all B has a fixation probability greater (smaller) than the neutral threshold 1/N, the inverse population size. We examine the case where at an A-frequency of 1/3, the fitness of an A player is exactly equal to the fitness of a B player. We find that in this case the relative magnitude of the cross payoffs matters: If the payoff of A against B is larger (smaller) than the payoff of B against A, then a single A mutant has a fixation probability larger (smaller) than 1/N. If the cross payoffs coincide, we are in the special case of a partnership game, where the deviation cost from an inefficient equilibrium is exactly balanced by the potential gain of switching to the payoff dominant equilibrium. We show that in this case the fixation probability of A is lower than 1/N. Finally, we illustrate our findings by a language game with differentiated costs of signals.  相似文献   
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