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排序方式: 共有127条查询结果,搜索用时 15 毫秒
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CHFR (Checkpoint with Forkhead-associated and RING finger domains) has been implicated in a checkpoint regulating entry into mitosis. However, the details underlying its roles and regulation are unclear due to conflicting lines of evidence supporting different notions of its functions. We provide here an overview of how CHFR is thought to contribute towards regulating mitotic entry and present possible explanations for contradictory observations published on the functions and regulation of CHFR. Furthermore, we survey key data showing correlations between promoter hypermethylation or down-regulation of CHFR and cancers, with a view on the likely reasons why different extents of correlations have been reported. Lastly, we explore the possibilities of exploiting CHFR promoter hypermethylation status in diagnostics and therapeutics for cancer patients. With keen interest currently focused on the association between hypermethylation of CHFR and cancers, details of how CHFR functions require further study to reveal how its absence might possibly contribute to tumorigenesis.  相似文献   
85.
Through genome-wide association meta-analyses of up to 133,010 individuals of European ancestry without diabetes, including individuals newly genotyped using the Metabochip, we have increased the number of confirmed loci influencing glycemic traits to 53, of which 33 also increase type 2 diabetes risk (q < 0.05). Loci influencing fasting insulin concentration showed association with lipid levels and fat distribution, suggesting impact on insulin resistance. Gene-based analyses identified further biologically plausible loci, suggesting that additional loci beyond those reaching genome-wide significance are likely to represent real associations. This conclusion is supported by an excess of directionally consistent and nominally significant signals between discovery and follow-up studies. Functional analysis of these newly discovered loci will further improve our understanding of glycemic control.  相似文献   
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Operculariidae includes sessile ciliate species mainly attached to diverse substrates, but records are scarce for their attachment to aquatic true bugs. The goal of this contribution is to provide new cytological data with optical and scanning electron microscopy of Orbopercularia lichtensteini, and some notes about their distribution on a Mexican corixid. We manually collected the corixids in a pond in Mexico during a six-month period, and all individuals were revised to observe the peritrichids. We calculated the abundance and prevalence, with an emphasis on the specific micro-location of the epibiotic peritrich on the host Corisella edulis. A total of 36,205 peritrichids were recorded in 158 corixids. The colonies with fine striated zooids were dichotomously branched and mostly attached to left eyes, but also on other body regions, i.e. left wings and rostrum. We conclude that some morphological colony traits bring some advantages for food particle capture, and aspects of the biology and morphology of Corisella edulis play an important role in determining the spatial distribution of O. lichtensteini.  相似文献   
88.
Exercise has beneficial effects on human health, including protection against metabolic disorders such as diabetes. However, the cellular mechanisms underlying these effects are incompletely understood. The lysosomal degradation pathway, autophagy, is an intracellular recycling system that functions during basal conditions in organelle and protein quality control. During stress, increased levels of autophagy permit cells to adapt to changing nutritional and energy demands through protein catabolism. Moreover, in animal models, autophagy protects against diseases such as cancer, neurodegenerative disorders, infections, inflammatory diseases, ageing and insulin resistance. Here we show that acute exercise induces autophagy in skeletal and cardiac muscle of fed mice. To investigate the role of exercise-mediated autophagy in vivo, we generated mutant mice that show normal levels of basal autophagy but are deficient in stimulus (exercise- or starvation)-induced autophagy. These mice (termed BCL2 AAA mice) contain knock-in mutations in BCL2 phosphorylation sites (Thr69Ala, Ser70Ala and Ser84Ala) that prevent stimulus-induced disruption of the BCL2-beclin-1 complex and autophagy activation. BCL2 AAA mice show decreased endurance and altered glucose metabolism during acute exercise, as well as impaired chronic exercise-mediated protection against high-fat-diet-induced glucose intolerance. Thus, exercise induces autophagy, BCL2 is a crucial regulator of exercise- (and starvation)-induced autophagy in vivo, and autophagy induction may contribute to the beneficial metabolic effects of exercise.  相似文献   
89.
磁控溅射是一项成熟的技术,可用在各种基体上沉积高质量金属及陶瓷涂层。然而,此项技术一般并不适于涂镀微粒粒度为nm或μm到100μm的细微粒涂层。本文详述了一种可涂镀微粒粒径在上述范围的均匀功能薄膜的技术。在磁场下面安放的一个碗状容器内放有微粒子,容器可以振动可使粒子均匀地振出碗边沉落到真空腔,薄膜沉积工艺为反应或非反应脉冲磁控溅射。Ti,Ti O2,Sn及Sn O2从单磁场源沉积,而Bi/W的氧化物从双磁场源沉积。用SEM,TEM和EDX,以及其它与应用相关的技术表征所沉积的微粒,以表明此项技术的潜在功能。  相似文献   
90.
Systemic risk in banking ecosystems   总被引:3,自引:0,他引:3  
Haldane AG  May RM 《Nature》2011,469(7330):351-355
In the run-up to the recent financial crisis, an increasingly elaborate set of financial instruments emerged, intended to optimize returns to individual institutions with seemingly minimal risk. Essentially no attention was given to their possible effects on the stability of the system as a whole. Drawing analogies with the dynamics of ecological food webs and with networks within which infectious diseases spread, we explore the interplay between complexity and stability in deliberately simplified models of financial networks. We suggest some policy lessons that can be drawn from such models, with the explicit aim of minimizing systemic risk.  相似文献   
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