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991.
Although up to 25% of children with autism are non-verbal, there are very few interventions that can reliably produce significant improvements in speech output. Recently, a novel intervention called Auditory-Motor Mapping Training (AMMT) has been developed, which aims to promote speech production directly by training the association between sounds and articulatory actions using intonation and bimanual motor activities. AMMT capitalizes on the inherent musical strengths of children with autism, and offers activities that they intrinsically enjoy. It also engages and potentially stimulates a network of brain regions that may be dysfunctional in autism. Here, we report an initial efficacy study to provide 'proof of concept' for AMMT. Six non-verbal children with autism participated. Prior to treatment, the children had no intelligible words. They each received 40 individual sessions of AMMT 5 times per week, over an 8-week period. Probe assessments were conducted periodically during baseline, therapy, and follow-up sessions. After therapy, all children showed significant improvements in their ability to articulate words and phrases, with generalization to items that were not practiced during therapy sessions. Because these children had no or minimal vocal output prior to treatment, the acquisition of speech sounds and word approximations through AMMT represents a critical step in expressive language development in children with autism.  相似文献   
992.
The equine herpesvirus 1 glycoprotein 14 (EHV-1 gp14) gene was cloned, sequenced, and expressed by vaccinia virus recombinants. Recombinant virus vP613 elicited the production of EHV-1-neutralizing antibodies in guinea pigs and was effective in protecting hamsters from subsequent lethal EHV-1 challenge. Coexpression of EHV-1 gp14 in vaccinia virus recombinant vP634 along with EHV-1 gp13 (P. Guo, S. Goebel, S. Davis, M. E. Perkus, B. Languet, P. Desmettre, G. Allen, and E. Paoletti, J. Virol. 63:4189-4198, 1989) greatly enhanced the protective efficacy in the hamster challenge model over that obtained with single recombinants. The inoculum doses (log10) required for protection of 50% of hamsters were 6.1 (EHV-1 gp13), 5.2 (EHV-1 gp14), and less than 3.6 (vaccinia virus recombinant expressing both EHV-1 glycoproteins [gp13 and gp14]).  相似文献   
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Nickerson , Norton H. (Washington U., St. Louis, Missouri.) Sustained treatment with gibberellic acid of maize plants carrying one of the dominant genes Teopod and Corn-grass. Amer. Jour. Bot. 47(10): 809–815. Illus. 1960.—Groups of field-grown plants of 2 dominant maize mutants, Corn-grass (Cg), and Teopod (Tp), were treated with either distilled water or with 1 of 3 concentrations of aqueous gibberellic acid (GA) every 3 days from the seedling stage until tassel emergence. Both dominant mutants were found to respond to GA in such manner that certain treated plants became essentially normal in phenotype. The role of GA in modifying expression of specific genes is briefly discussed.  相似文献   
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The polypeptide omega-conotoxin GVIA (GVIA) is an N-type calcium channel blocker from the venom of Conus geographus, a fish-hunting cone shell. Here we describe a high-resolution solution structure of this member of the 'inhibitor cystine knot' protein family. The structure, based on NMR data acquired at 600 MHz, has mean pairwise RMS differences of 0.25 +/- 0.06 and 1.07 +/- 0.14 A over the backbone heavy atoms and all heavy atoms, respectively. The solvent-accessible side chains are better defined than in previously published structures and provide an improved basis for docking GVIA with models of the calcium channel. Moreover, some side chain interactions important in GVIA folding in vitro and in stabilizing the native structure are defined clearly in the refined structure. Two qualitatively different backbone conformations in the segment from Thr11 to Asn14 persisted in the restrained simulated annealing calculations until a small number of lower bound constraints was included to prevent close contacts from occurring that did not correspond with peaks in the NOESY spectrum. It is possible that GVIA is genuinely flexible at this segment, spending a finite time in the alternative conformation, and this may influence its interaction with the calcium channel.  相似文献   
999.
Co-gels of potato maltodextrin Paselli SA-6 with gelatin were prepared by rapid quenching of mixed solutions from 90°C. At fixed setting temperature and fixed concentration of gelatin, the time required to form a self-supporting network showed an initial steady decrease with increasing concentration of SA-6 (as expected from polymer exclusion), but then increased dramatically before again decreasing. The interpretation of this behaviour as phase inversion from a gelatin-continuous network with SA-6 inclusions to a (more slowly-forming) SA-6 network with gelatin inclusions was confirmed by differential scanning calorimetry (showing both components melting separately, with no evidence of specific interaction), mechanical spectroscopy (showing that the mixed gel network was destroyed completely by melting of the gelatin component at low concentrations of SA-6, but only weakened at SA-6 concentrations above the inversion point) and by light microscopy (showing the expected changes in distribution of the two polymers).

In similar studies using the faster-gelling potato maltodextrin Paselli SA-2, microscopy and gel-melting profiles again showed phase-inversion from a gelatin-continuous network at low concentrations of SA-2 to a maltodextrin-continuous network at higher concentrations. Inversion, however, occurred at a lower concentration of maltodextrin than in the gelatin/SA-6 systems, and the accompanying change in gelation rate was confined to a sharp decrease in the dependence of gel-time on SA-2 concentration.  相似文献   

1000.
Efficacy of cancer chemotherapy is generally believed to be the result of direct drug killing of tumor cells. However, increased tumor cell killing does not always lead to improved efficacy. Herein, we demonstrate that the status of antitumor immunity at the time of chemotherapy treatment is a critical factor affecting the therapeutic outcome in that tumor-bearing mice that possess preexisting antitumor immunity respond to chemotherapy much better than those that do not. Enhancing antitumor immunity before or at the time of chemotherapy-induced antigen release increases subsequent response to chemotherapy significantly. By in vitro and in vivo measurements of antitumor immunity, we found a close correlation between the intensity of antitumor immunity activated by chemotherapy and the efficacy of treatment. Immune intervention with interleukin-12 during the early phase of chemotherapy-induced immune activation greatly amplifies the antitumor response, often resulting in complete tumor eradication not only at the chemo-treated local site, but also systemically. These findings provide additional evidence for an immune-mediated antitumor response to chemotherapy. Further, our results show that timely immune modification of chemotherapy-activated antitumor immunity can result in enhanced antitumor-immune response and complete tumor eradication.  相似文献   
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