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71.

Introduction

Recent studies have demonstrated that inactivated seasonal influenza vaccines (IIV) may elicit production of heterosubtypic antibodies, which can neutralize avian H5N1 virus in a small proportion of subjects. We hypothesized that prime boost regimens of live and inactivated trivalent seasonal influenza vaccines (LAIV and IIV) would enhance production of heterosubtypic immunity and provide evidence of cross-protection against other influenza viruses.

Methods

In an open-label study, 26 adult volunteers were randomized to receive one of four vaccine regimens containing two doses of 2009-10 seasonal influenza vaccines administered 8 (±1) weeks apart: 2 doses of LAIV; 2 doses of IIV; LAIV then IIV; IIV then LAIV. Humoral immunity assays for avian H5N1, 2009 pandemic H1N1 (pH1N1), and seasonal vaccine strains were performed on blood collected pre-vaccine and 2 and 4 weeks later. The percentage of cytokine-producing T-cells was compared with baseline 14 days after each dose.

Results

Subjects receiving IIV had prompt serological responses to vaccine strains. Two subjects receiving heterologous prime boost regimens had enhanced haemagglutination inhibition (HI) and neutralization (NT) titres against pH1N1, and one subject against avian H5N1; all three had pre-existing cross-reactive antibodies detected at baseline. Significantly elevated titres to H5N1 and pH1N1 by neuraminidase inhibition (NI) assay were observed following LAIV-IIV administration. Both vaccines elicited cross-reactive CD4+ T-cell responses to nucleoprotein of avian H5N1 and pH1N1. All regimens were safe and well tolerated.

Conclusion

Neither homologous nor heterologous prime boost immunization enhanced serum HI and NT titres to 2009 pH1N1 or avian H5N1 compared to single dose vaccine. However heterologous prime-boost vaccination did lead to in vitro evidence of cross-reactivity by NI; the significance of this finding is unclear. These data support the strategy of administering single dose trivalent seasonal influenza vaccine at the outset of an influenza pandemic while a specific vaccine is being developed.

Trial Registration

ClinicalTrials.gov NCT01044095  相似文献   
72.
Digital reconstruction of three-dimensional (3D) neuronal morphology from light microscopy images provides a powerful technique for analysis of neural circuits. It is time-consuming to manually perform this process. Thus, efficient computer-assisted approaches are preferable. In this paper, we present an innovative method for the tracing and reconstruction of 3D neuronal morphology from light microscopy images. The method uses a prediction and refinement strategy that is based on exploration of local neuron structural features. We extended the rayburst sampling algorithm to a marching fashion, which starts from a single or a few seed points and marches recursively forward along neurite branches to trace and reconstruct the whole tree-like structure. A local radius-related but size-independent hemispherical sampling was used to predict the neurite centerline and detect branches. Iterative rayburst sampling was performed in the orthogonal plane, to refine the centerline location and to estimate the local radius. We implemented the method in a cooperative 3D interactive visualization-assisted system named flNeuronTool. The source code in C++ and the binaries are freely available at http://sourceforge.net/projects/flneurontool/. We validated and evaluated the proposed method using synthetic data and real datasets from the Digital Reconstruction of Axonal and Dendritic Morphology (DIADEM) challenge. Then, flNeuronTool was applied to mouse brain images acquired with the Micro-Optical Sectioning Tomography (MOST) system, to reconstruct single neurons and local neural circuits. The results showed that the system achieves a reasonable balance between fast speed and acceptable accuracy, which is promising for interactive applications in neuronal image analysis.  相似文献   
73.
A halotolerant bacterium, strain SMB34T, was isolated from a naphthalene-utilizing bacterial consortium obtained from primitive technogeneous soil (Verkhnekamsk salt deposit, Perm region, Russia) by enrichment procedure. The strain itself was unable to degrade naphthalene and grew at NaCl concentrations up to 11% (w/v). The 16S rRNA-based phylogenetic analysis showed that the strain belongs to the genus Thalassospira. The DNA-DNA hybridization values between SMB34T and the type strains of phylogeneti-cally closest species (T. xiamenensis, T. profundimaris and T. tepidiphila) did not exceed 50%. The novel strain could be distinguished from the above species by the cell motility, MALDI/TOF mass spectra of whole cells and a range of physiological and biochemical characteristics. SMB34T also considerably differs from the recently described species T. xianhensis, with the most striking differences in the DNA G + C content (53. ± 1.0 vs. 61.2 ± 1.0 mol %) and predominant ubiquinones (Q-10 vs. Q-9). The data obtained suggest strain SMB34T (=VKM B-2527T = NBRC 106175T), designated as the type strain, represents a novel species, named Thalassospira permensis sp. nov.  相似文献   
74.
云南松SSR-PCR反应体系的建立与优化   总被引:1,自引:0,他引:1  
为了建立适宜云南松SSR-PCR的反应体系和扩增程序,利用近缘种火炬松的引物,采用正交设计L16(45)对云南松SSR-PCR反应体系的5因素(Taq酶、Mg2+、模板DNA、dNTP、引物)在4个水平上进行优化,筛选出各反应因素的最佳水平,建立了适于云南松的SSR反应体系.在10μL的反应体系中,模板DNA的用量为30.0 ng,Taq DNA聚合酶的用量为1.0 U,Mg2+的浓度为2.0 mmol/L,dNTPs浓度为0.4 mmol/L,引物的浓度为0.2 μmol/L.扩增程序为:94℃预变性4 min;94℃变性45 s,48℃退火30 s,72℃延伸30 s,30个循环;72℃延长10 min,4℃保存.最后利用1个居群对该体系进行稳定性验证,结果可用于云南松SSR标记的研究.  相似文献   
75.
Biodiesel-contaminated wastewater was used to screen for PHAs-producing bacteria by using crude glycerol as the sole carbon source. A gram-negative THA_AIK7 isolate was chosen as a potential PHAs producer. The 16S rRNA phylogeny indicated that THA_AIK7 isolate is a member of Novosphingobium genus which is supported by a bootstrap percentage of 100% with Novosphingobium capsulatum. The 1,487 bp of 16S rRNA gene sequence of THA_AIK7 isolate has been deposited in the GenBank database under the accession number HM031593. Polymer content of 45% cell dry weight was achieved in 72 h with maximum product yield coefficient of 0.29 g PHAs g?1 glycerol. Transmission electron micrograph results exhibited the PHAs granules accumulated inside the bacterial cell. PHAs polymer production in mineral salt media supplemented with 2% (w/v) of crude glycerol at initial pH 7 was extracted by the sodium hypochlorite method. Polymer film spectrographs from Nuclear magnetic resonance displayed a pattern of signal virtually identical to spectra of commercial PHB. Thermal analysis by Differential scanning calorimeter showed a melting temperature at 179°C. Molecular weight analysis by Gel permeation chromatography showed two main peaks of 133,000 and 700 g mol?1 with weight-average molecular weight value of 23,800 and number-average molecular weight value of 755. Endotoxinfree of PHAs polymer was preliminarily assessed by a negative result of the gel-clot formation, Pyrotell? Single test vial, at sensitivity of 0.25 EU ml?1. To our knowledge, this is the first reported test of endotoxin-free PHAs naturally produced from gram-negative bacteria which could be used for biomedical application.  相似文献   
76.
The compartmentalization of cell cycle regulators is a common mechanism to ensure the precise temporal control of key cell cycle events. For instance, many mitotic spindle assembly factors are known to be sequestered in the nucleus prior to mitotic onset. Similarly, the essential cytokinetic factor anillin, which functions at the cell membrane to promote the physical separation of daughter cells at the end of mitosis, is sequestered in the nucleus during interphase. To address the mechanism and role of anillin targeting to the nucleus in interphase, we identified the nuclear targeting motif. Here, we show that anillin is targeted to the nucleus by importin β2 in a Ran-dependent manner through an atypical basic patch PY nuclear localization signal motif. We show that although importin β2 binding does not regulate anillin''s function in mitosis, it is required to prevent the cytosolic accumulation of anillin, which disrupts cellular architecture during interphase. The nuclear sequestration of anillin during interphase serves to restrict anillin''s function at the cell membrane to mitosis and allows anillin to be rapidly available when the nuclear envelope breaks down to remodel the cellular architecture necessary for successful cell division.  相似文献   
77.
We have isolated cDNA clones of the mRNA for rat UDP-glucuronosyltransferase that catalyzes the glucuronidation of 4-nitrophenol, by using synthetic oligonucleotides as hybridization probes. The complete nucleotide sequence of the 1,927-base pairs cDNA insert has been determined. With untranslated sequences of 124 and 216 base pairs in the 5'- and 3'-terminal regions, respectively, the cDNA insert contained 1,587 base pairs that encode a complete primary structure of a putative precursor form of 4-nitrophenol UDP-glucuronosyltransferase with a calculated molecular weight of 60,114. The cDNA sequence also indicates the presence of 25 amino acids preceding the sequence determined by microsequence of the isolated protein. This extrapeptide, for the most part, consists of hydrophobic amino acids which are characteristic of the signal peptides as found for secretory proteins and most transmembrane proteins. Furthermore, the deduced amino acid sequence contains a putative halt transfer signal of a hydrophobic segment (residues 487-510), which is flanked on both sides by the peptide segments of highly charged amino acid residues (residues 463-486 and 511-529). These features are consistent with the properties of transmembrane proteins. Specific cDNA probes were used to analyze the induction of the enzyme in rat tissues by treatment with 3-methylcholanthrene. RNA blot analysis showed that 3-methylcholanthrene increased 10- to 15-fold the amount of hybridizable mRNA in liver. The livers and kidneys from 3-methylcholanthrene-treated rats were found to contain almost the same amount of hybridizable mRNA, although the basal level in the kidney was much higher than that of the liver, and the amounts in the lung were much lower than that of the liver and kidney.  相似文献   
78.
Morphofunctional characteristics of industrial microorganisms belonging to different genera, species, and strains were investigated after 15 to 20 years of storage in liquid nitrogen. The taxonomic position of microorganisms, the cell physiological state prior to storage, and the cryoconservation regime were found to affect microbial cryoresistance. Protective media, density of cell suspensions, freezing rate, and heating temperature are the parameters important for development of efficient technologies for cryoconservation of industrial microorganisms at ?196°C.  相似文献   
79.
80.
Results are presented from experimental studies of the dynamics and parameters of the plasma generated by megampere (up to 2.3 MA) currents flowing through X-pinches formed from crossed wires made of various materials. The experiments were performed with different numbers of wires and different wire diameters. The X-ray yield in neon-like molybdenum lines (in the 2.5- to 3-keV photon energy range) from a <20 μm hot spot was larger than 10 J, and the soft X-ray power emitted from this spot reached 120 GW. The hot-spot lifetime estimated by comparing the measured and calculated emission intensities and line profiles of helium-like Fe and Cr ions was ~10 ps. Hard X-ray emission in the photon energy range ≥800 keV was also detected.  相似文献   
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