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Impaired social brain network for processing dynamic facial expressions in autism spectrum disorders
ABSTRACT: BACKGROUND: Impairment of social interaction via facial expressions represents a core clinical feature of autism spectrum disorders (ASD). However, the neural correlates of this dysfunction remain unidentified. Because this dysfunction is manifested in real-life situations, we hypothesized that the observation of dynamic, compared with static, facial expressions would reveal abnormal brain functioning in individuals with ASD. We presented dynamic and static facial expressions of fear and happiness to individuals with high-functioning ASD and to age- and sex-matched typically developing controls and recorded their brain activities using functional magnetic resonance imaging (fMRI). Result Regional analysis revealed reduced activation of several brain regions in the ASD group compared with controls in response to dynamic versus static facial expressions, including the middle temporal gyrus (MTG), fusiform gyrus, amygdala, medial prefrontal cortex, and inferior frontal gyrus (IFG). Dynamic causal modeling analyses revealed that bi-directional effective connectivity involving the primary visual cortex-MTG-IFG circuit was enhanced in response to dynamic as compared with static facial expressions in the control group. Group comparisons revealed that all these modulatory effects were weaker in the ASD group than in the control group. CONCLUSIONS: These results suggest that weak activity and connectivity of the social brain network underlie the impairment in social interaction involving dynamic facial expressions in individuals with ASD. 相似文献
123.
Some trigonometric functions can be expressed by the infinite composition of polynomials. First we need to consider the convergence problem to study infinite compositions of functions. This article discusses the convergence of infinite compositions of entire functions whose constant terms are not necessarily zero. 相似文献
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Dillon T. Flood Xuejing Zhang Xiang Fu Zhenxiang Zhao Shota Asai Brittany B. Sanchez Emily J. Sturgell Julien C. Vantourout Paul Richardson Mark E. Flanagan David W. Piotrowski Dominik K. Kölmel Jinqiao Wan Mei-Hsuan Tsai Jason S. Chen Phil S. Baran Philip E. Dawson 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(19):7447-7453
DNA encoded libraries (DEL) have shown promise as a valuable technology for democratizing the hit discovery process. Although DEL provides relatively inexpensive access to libraries of unprecedented size, their production has been hampered by the idiosyncratic needs of the encoding DNA tag relegating DEL compatible chemistry to dilute aqueous environments. Recently reversible adsorption to solid support (RASS) has been demonstrated as a promising method to expand DEL reactivity using standard organic synthesis protocols. Here we demonstrate a suite of on-DNA chemistries to incorporate medicinally relevant and C−S, C−P and N−S linkages into DELs, which are underrepresented in the canonical methods. 相似文献
127.
A Core‐Expanded Subphthalocyanine Analogue with a Significantly Distorted Conjugated Surface and Unprecedented Properties
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Dr. Soji Shimizu Shota Nakano Ayaka Kojima Prof. Nagao Kobayashi 《Angewandte Chemie (International ed. in English)》2014,53(9):2408-2412
The introduction of a seven‐membered‐ring unit in the place of a five‐membered‐ring unit in the structure of subphthalocyanine resulted in significant distortion of the bowl‐shaped structure of the conjugated molecule as well as the following unprecedented properties: the preferential formation of the axially fluoro substituted species, the fluttering‐dynamic‐motion‐induced rapid exchange of P and M enantiomers, markedly split Q‐band absorption, and a clear difference in the ring‐current effects arising from the convex and concave surfaces. 相似文献
128.
Kentaro Takahama Asami Takada Shota Tada Mai Shimizu Kazutoshi Sayama Riki Kurokawa Takanori Oyoshi 《Chemistry & biology》2013,20(3):341-350
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129.
Hayato Inoue Takayuki Yamamoto Dr. Shota Kuwahara Prof. Dr. Kenji Katayama 《化学:亚洲杂志》2013,8(1):108-112
In‐situ extraction and condensation of various dyes were carried out in a phase‐separation region of a thermoresponsive polymer aqueous solution generated by near infrared (NIR) laser heating under a microscope. The NIR laser irradiation was directed at a chromium line deposited on a glass substrate, thereby causing local heating of the solution due to the photothermal effect. A phase‐separation region was formed by dehydration of the thermoresponsive polymer followed by ejection of water outside of the phase‐separation region. When various dyes were included in the solution, some dye molecules were extracted into the phase‐separation region, where they condensed. In the case of poly(N‐isopropylacrylamide) (PNIPAM, 10 wt % in an aqueous solution) as the thermoresponsive polymer and crystal violet (CV) as the dye (0.1 mM ), CV condensed by about 25 times. It was found that one of the necessary conditions for the extraction/condensation is the hydrophobicity of the dye molecule; however, the dominant cause for accumulating inside the PNIPAM chain is the molecular interaction between the amide group in the side chain of PNIPAM and the functional groups such as carbonyl or amino groups in the dye molecules. 相似文献
130.
Dillon T. Flood Xuejing Zhang Xiang Fu Zhenxiang Zhao Shota Asai Brittany B. Sanchez Emily J. Sturgell Julien C. Vantourout Paul Richardson Mark E. Flanagan David W. Piotrowski Dominik K. Klmel Jinqiao Wan Mei‐Hsuan Tsai Jason S. Chen Phil S. Baran Philip E. Dawson 《Angewandte Chemie (International ed. in English)》2020,59(19):7377-7383
DNA encoded libraries (DEL) have shown promise as a valuable technology for democratizing the hit discovery process. Although DEL provides relatively inexpensive access to libraries of unprecedented size, their production has been hampered by the idiosyncratic needs of the encoding DNA tag relegating DEL compatible chemistry to dilute aqueous environments. Recently reversible adsorption to solid support (RASS) has been demonstrated as a promising method to expand DEL reactivity using standard organic synthesis protocols. Here we demonstrate a suite of on‐DNA chemistries to incorporate medicinally relevant and C?S, C?P and N?S linkages into DELs, which are underrepresented in the canonical methods. 相似文献