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Alan Coulson Yoko Kozono Bart Lutterbach Ratna Shownkeen John Sulston Robert Waterston 《BioEssays : news and reviews in molecular, cellular and developmental biology》1991,13(8):413-417
During the past decade, it has become apparent that it is within our grasp to understand fully the development and functioning of complex organisms. It is widely accepted that this undertaking must include the elucidation of the genetic blueprint – the genome sequence – of a number of model organisms. As a prelude to the determination of these sequences, clonebased physical maps of the genomes of a number of multicellular animals and plants are being constructed. Yeast artificial chromosome (YAC) vectors, by virtue of their relatively unbiased cloning capabilities and capacity to carry large inserts, have come to play a central role in the construction of these maps. The application of YACs to the physical map of the Caenorhabditis elegans genome has enabled cosmid clone ‘islands’ to be linked together in an efficient manner. The long-range continuity has improved the linkage between the genetic and physical maps, greatly increasing its utility. Since the genome can be represented by a relatively small number of YACs, it has been possible to make replica filters of genomically ordered YACs available to the community at large. 相似文献
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Wulan T. Wahyuni Tribidasari A. Ivandini Endang Saepudin Yasuaki Einaga 《Analytical biochemistry》2016
Gold nanoparticles-modified boron-doped diamond (AuNPs–BDD) electrodes, which were prepared with a self-assembly deposition of AuNPs at amine-terminated boron-doped diamond, were examined for voltammetric detection of neuraminidase (NA). The detection method was performed based on the difference of electrochemical responses of zanamivir at gold surface before and after the reaction with NA in phosphate buffer solution (PBS, pH 5.5). A linear calibration curve for zanamivir in 0.1 M PBS in the absence of NA was achieved in the concentration range of 1 × 10−6 to 1 × 10−5 M (R2 = 0.99) with an estimated limit of detection (LOD) of 2.29 × 10−6 M. Furthermore, using its reaction with 1.00 × 10−5 M zanamivir, a linear calibration curve of NA can be obtained in the concentration range of 0–12 mU (R2 = 0.99) with an estimated LOD of 0.12 mU. High reproducibility was shown with a relative standard deviation (RSD) of 1.14% (n = 30). These performances could be maintained when the detection was performed in mucin matrix. Comparison performed using gold-modified BDD (Au–BDD) electrodes suggested that the good performance of the detection method is due to the stability of the gold particles position at the BDD surface. 相似文献
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The spontaneous activity of the brain is dynamic even at rest and the deviation from this normal pattern of dynamics can lead to different pathological states. EEG microstate analysis of resting-state neuronal activity in Parkinson’s disease (PD) could provide insight into altered brain dynamics of patients exhibiting dementia. Resting-state EEG microstate maps were derived from 128 channel EEG data in 20 PD without dementia (PDND), 18 PD with dementia (PDD) and 20 Healthy controls (CON) using Cartool and sLORETA softwares. Microstate map parameters including global explained variance, mean duration, frequency of occurrence (TF) and time coverage were compared statistically among the groups. Eight maps that explained 72% of the topographic variance were identified and only three maps differed significantly across the groups. TF of Map1 was lower in both PDND and PDD (p < 0.001) and that of Map3 (p = 0.02) in PDND compared to control. Cortical sources showed higher activation in precuneus, cuneus and superior parietal lobe (Threshold: Log-F = 1.74, p < 0.05) with maximum activity in the precuneus region (MNI co-ordinates: − 25, − 75, − 40; Log-F = 1.9) in PDND compared to control only for Map1. Lower TF of Map1 (prototypical microstate D) may potentially serve as a biomarker for PD with or without dementia whereas higher activation of precuneus, cuneus and superior parietal lobe at resting-state could favour signal processing, lack of which could be associated with dementia in Parkinson’s disorder. 相似文献
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Biocompatibility and Conductometric Property of Sol-Gel Derived ZnO/PVP Nanocomposite Biosensor Film
Nanocrystalline ZnO and ZnO/PVP nanocomposite films have been prepared by the sol-gel dip-coating technique from zinc acetate precursor on silicon wafer and Pyrex glass substrates. The films were characterized using atomic force microscopy for morphology, and X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy for chemical analysis. Thermally untreated and annealed films were studied in order to analyze the influence of temperature on the formation and properties of the films. The films have a uniform void-free surface and the grain size increases with the annealing temperature. The cell viability assays indicate that the growth rate of BPH cells incubated in the presence of ZnO was significantly reduced (35% of the control) compared to that of untreated controls, indicating antibacterial activity of ZnO as a result of the generation of hydrogen peroxide. The sensor characteristic of ZnO/PVP nanocomposite was also demonstrated by measuring the change in conductivity upon exposure to superoxide anion radical. 相似文献
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The open nature of communication medium in wireless networks becomes easy for the attackers to indulge in jamming attack. Jamming blocks the communication channel with the intent of preventing the flow of useful information. Jammers effectively and stealthy corrupts the packet by injecting high level of noise thereby keeping the channel busy so that the legitimate traffic gets completely blocked, resulting in packet loss at the receiver side. Securing the information from the jammers has become very important. Therefore an effective approach is needed to prevent this attack and this paper proposes Discriminate based Misbehavior Prevention DMP scheme to identify and to detach the jammer that corrupts the packet in wireless network. The proposed scheme consists of three modules. In module one, the log files are analyzed and using the trusting mechanism the suspected traces are identified. In module two, three reshuffling algorithms has been developed for reshuffling and identifying doubtful traces. In module three, the jammer nodes are identified and detached from the network. By simulation studies, it is observed that the proposed scheme attains higher throughput and packet delivery ratio while attaining lower delay. 相似文献
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