首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   155篇
  免费   6篇
  国内免费   8篇
  2023年   1篇
  2022年   3篇
  2021年   1篇
  2020年   3篇
  2019年   1篇
  2018年   10篇
  2017年   2篇
  2016年   3篇
  2015年   3篇
  2014年   5篇
  2013年   15篇
  2012年   7篇
  2011年   10篇
  2010年   10篇
  2009年   12篇
  2008年   12篇
  2007年   3篇
  2006年   10篇
  2005年   6篇
  2004年   9篇
  2003年   3篇
  2002年   1篇
  2001年   1篇
  2000年   3篇
  1999年   3篇
  1996年   3篇
  1994年   1篇
  1993年   1篇
  1992年   2篇
  1990年   1篇
  1987年   3篇
  1985年   2篇
  1983年   1篇
  1982年   1篇
  1981年   1篇
  1980年   1篇
  1979年   2篇
  1978年   3篇
  1977年   1篇
  1976年   2篇
  1975年   2篇
  1974年   1篇
  1973年   4篇
排序方式: 共有169条查询结果,搜索用时 15 毫秒
161.
HBNU/LSRC/F3, a Newcastle disease virus (NDV) strain stored in our lab, exhibited an anti-tumor ability in our previous studies. Nonetheless, very little is known about its genome sequence, which is vital for further study. Here, the complete HBNU/LSRC/F3 genome was fully sequenced and compared with other NDV sequences. Its genome contained 15,192 nucleotides (nt) consisting of two termini and six genes in the following order: 3′-Le-NP-P-M-F-HN-L-Tr-5′. Phylogenetic analysis indicated that this NDV strain belonged to the Class II genotype IX group. A multibasic amino acid (aa) sequence was found at the cleavage site (112RRQRR↓F117) within the fusion (F) protein, and a 6 nt insertion was present in the 5′ non-coding region of the NP gene. The whole genome sequence was highly similar to other genotype IX NDV genomes reported in China. Overall, this study provides insight into the sequence characteristics of genotype IX NDVs, which will be useful for subsequent investigations.  相似文献   
162.
Membrane fusion is an essential step of the internalization process of the enveloped animal viruses. Vesicular stomatitis virus (VSV) infection is mediated by virus spike glycoprotein G, which induces membrane fusion at the acidic environment of the endosomal compartment. In a previous work, we identified a specific sequence in VSV G protein, comprising the residues 145 to 164, directly involved in membrane interaction and fusion. Unlike fusion peptides from other viruses, this sequence is very hydrophilic, containing six charged residues, but it was as efficient as the virus in catalyzing membrane fusion at pH 6.0. Using a carboxyl-modifying agent, dicyclohexylcarbodiimide (DCCD), and several synthetic mutant peptides, we demonstrated that the negative charges of peptide acidic residues, especially Asp153 and Glu158, participate in the formation of a hydrophobic domain at pH 6.0, which is necessary to the peptide-induced membrane fusion. The formation of the hydrophobic region and the membrane fusion itself were dependent on peptide concentration in a higher than linear fashion, suggesting the involvement of peptide oligomerization. His148 was also necessary to hydrophobicity and fusion, suggesting that peptide oligomerization occurs through intermolecular electrostatic interactions between the positively-charged His and a negatively-charged acidic residue of two peptide molecules. Oligomerization of hydrophilic peptides creates a hydrophobic region that is essential for the interaction with the membrane that results in fusion.  相似文献   
163.
In this chapter we shall describe how to apply the hydrophobicity-at-interface scale, as proposed by Wimley and White [Wimley, W. C. and White, S. H. (1996) Nature Struct. Biol. 3:842–848], to the detection of amino acid sequences of viral envelope glycoproteins putatively engaged in interactions with the target membranes. In addition, a new approach will be briefly introduced to infer the bilayer location at equilibrium of membrane-partitioning sequences. The use of these new procedures may be important in describing the molecular mechanism leading to the formation of a fusion pore by viral glycoproteins.  相似文献   
164.
E De Cercq  M Luczak 《Life sciences》1975,17(2):187-194
Some recent studies relating the effects of individual housing (isolation) and group housing to behavior, physiology and neurochemistry in laboratory rats and mice are reviewed and these accounts related to comparable information derived from experiments employing “social stresses” e.g. subjecting the animal to defeat. The data is discussed in relation to the problem of whether individual housing constitutes a “stress” (in terms of adrenocortical and adrenal medullary functioning) in these species, as it appears to do in primates. In spite of the large number of papers which ascribe the behavioral and endocrine changes obtained in isolation versus grouping comparisons to the effects of “the isolation-induced stress syndrome”, it is concluded that, in terms of adrenal function, there is little evidence that isolation perse constitutes a stress in rats and mice, although there is some evidence that adrenocortical reactivity is increased by housing animals in this manner. It should be noted that the wild progenitor of the laboratory strains of house mouse often appears to evidence territoriality. The view is advanced that the isolated condition in male mice may result in changes characteristic of territorial dominance. This may represent a mechanism for inducing social or territorial stability in this species. It appears that experiments involving physical isolation in laboratory rodents are unlikely to provide good models for the effects of “social deprivation” in man. It is thought that more studies employing measurement of hormone titers in biological samples, obtained as a result of non-stressful procedures, will lead to a clearer understanding of the effects seen in isolation versus grouping studies. Organ weight studies often appear to be very misleading, particularly in female rodents. It is also hoped that other studies will concern themselves with effects of isolation with respect to other social cues in rodents including odors and ultrasound.  相似文献   
165.
doi:10.1111/j.1741‐2358.2009.00359.x
The prevalence of denture stomatitis and its predisposing conditions in an older Greek population Background: Pathology related to complete denture‐wearing will remain an important issue because of an increase in the ageing population. Objective: To investigate the prevalence and the risk factors for denture‐related stomatitis in the edentulous maxilla of older patients with a maxillary complete denture. Material and methods: One hundred and six patients treated in the Department of Prosthodontics of the Athens Dental School were interviewed and clinically examined. The results were analysed using chi‐square tests and multiple logistic regression. Results: Denture stomatitis was recorded in 39.6% of the sample (pinpoint hyperaemia: 17%, diffuse erythema: 16%, papillary hyperplasia: 6.6%). Chi‐square tests recorded significant associations between denture stomatitis and the continuous use of dentures (particularly the diffuse erythema type), the increased duration of denture experience and the poor retention of the maxillary denture. Other significant associations were recorded between the increased age of the current denture and pinpoint hyperaemia, and the reduced frequency of denture cleaning and papillary hyperplasia. Multiple logistic analysis revealed that the most important risk factor for denture stomatitis was the continuous use of the denture. Conclusion: The prevalence of denture stomatitis was high in denture users. Although many predisposing conditions were recorded, the most important risk factor was the continuous use of the denture. Therefore, appropriate advice on denture maintenance should be provided.  相似文献   
166.
Type I and III interferons induce expression of the “myxovirus resistance proteins” MxA in human cells and its ortholog Mx1 in murine cells. Human MxA forms cytoplasmic structures, whereas murine Mx1 forms nuclear bodies. Whereas both HuMxA and MuMx1 are antiviral toward influenza A virus (FLUAV) (an orthomyxovirus), only HuMxA is considered antiviral toward vesicular stomatitis virus (VSV) (a rhabdovirus). We previously reported that the cytoplasmic human GFP-MxA structures were phase-separated membraneless organelles (“biomolecular condensates”). In the present study, we investigated whether nuclear murine Mx1 structures might also represent phase-separated biomolecular condensates. The transient expression of murine GFP-Mx1 in human Huh7 hepatoma, human Mich-2H6 melanoma, and murine NIH 3T3 cells led to the appearance of Mx1 nuclear bodies. These GFP-MuMx1 nuclear bodies were rapidly disassembled by exposing cells to 1,6-hexanediol (5%, w/v), or to hypotonic buffer (40–50 mosm), consistent with properties of membraneless phase-separated condensates. Fluorescence recovery after photobleaching (FRAP) assays revealed that the GFP-MuMx1 nuclear bodies upon photobleaching showed a slow partial recovery (mobile fraction: ∼18%) suggestive of a gel-like consistency. Surprisingly, expression of GFP-MuMx1 in Huh7 cells also led to the appearance of GFP-MuMx1 in 20–30% of transfected cells in a novel cytoplasmic giantin-based intermediate filament meshwork and in cytoplasmic bodies. Remarkably, Huh7 cells with cytoplasmic murine GFP-MuMx1 filaments, but not those with only nuclear bodies, showed antiviral activity toward VSV. Thus, GFP-MuMx1 nuclear bodies comprised phase-separated condensates. Unexpectedly, GFP-MuMx1 in Huh7 cells also associated with cytoplasmic giantin-based intermediate filaments, and such cells showed antiviral activity toward VSV.  相似文献   
167.
doi: 10.1111/j.1741‐2358.2012.00661.x Treatment protocol for denture stomatitis, prior to anatomical molding Background: Microorganisms of the genus Candida have been recovered from complete dentures made of acrylic resin, with high numbers of colony forming units and species diversity, which can act as infectious agents causing chronic atrophic candidiasis (denture stomatitis). Objective: The objective of this paper is present a treatment protocol for chronic atrophic candidiasis (denture stomatitis). Materials and Methods: The work describes three cases of totally edentulous patients presenting palate stomatitis who were submitted for treatment associating denture rebasing with chemically‐activated acrylic resin, night immersion in 2.5% sodium hypochlorite and use of topical antifungals for two weeks. Results: In all cases, remission of the inflammatory process occurred. Conclusion: The proposed treatment protocol proved to be to be effective.  相似文献   
168.
169.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号