全文获取类型
收费全文 | 190篇 |
免费 | 5篇 |
专业分类
电工技术 | 4篇 |
化学工业 | 44篇 |
金属工艺 | 7篇 |
机械仪表 | 18篇 |
建筑科学 | 2篇 |
矿业工程 | 1篇 |
能源动力 | 13篇 |
轻工业 | 4篇 |
无线电 | 14篇 |
一般工业技术 | 50篇 |
冶金工业 | 7篇 |
自动化技术 | 31篇 |
出版年
2022年 | 4篇 |
2021年 | 5篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 3篇 |
2017年 | 9篇 |
2016年 | 11篇 |
2015年 | 1篇 |
2014年 | 11篇 |
2013年 | 28篇 |
2012年 | 15篇 |
2011年 | 19篇 |
2010年 | 10篇 |
2009年 | 20篇 |
2008年 | 5篇 |
2007年 | 9篇 |
2006年 | 2篇 |
2005年 | 2篇 |
2004年 | 2篇 |
2003年 | 5篇 |
2002年 | 2篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有195条查询结果,搜索用时 15 毫秒
191.
Madalina Gabriela Barbu Dana Claudia Thompson Nicolae Suciu Silviu Cristian Voinea Dragos Cretoiu Dragos Valentin Predescu 《International journal of molecular sciences》2021,22(6)
MicroRNAs applications were vastly studied throughout the years, spanning from potential cancer biomarkers to targeted therapies for various diseases. Out of these utilizations, this paper focuses on their role in male infertility. Approximately 10–15% of worldwide couples are affected by infertility. Out of these, 50% are due to male determinants. The majority of cases still have an undetermined cause. Previous studies have found that the aberrant expression of microRNAs could be linked to certain reproductive dysfunctions in males. Further on, this study looked into the most recent literature published on this subject in order to assess the connection between the up-/down-regulation of various microRNAs and the roles they play in male infertility. MicroRNAs were found to be abundant and stable in the seminal liquid, which led to a facile identification using regular RNA detection methods. It was observed that the concentration of microRNAs in semen was modified in the case of patients suffering from asthenozoospermia and azoospermia. Moreover, idiopathic male infertility was associated with a single nucleotide polymorphism of the microRNA binding site. Future studies should focus their attention on discovering future treatments against male infertility targeting specific microRNAs and also on developing new and improved contraceptive methods. 相似文献
192.
Carmen Elena Condrat Valentin Nicolae Varlas Florentina Duic Panagiotis Antoniadis Cezara Alina Danila Dragos Cretoiu Nicolae Suciu Sanda Maria Creoiu Silviu Cristian Voinea 《International journal of molecular sciences》2021,22(8)
Extracellular vesicles (EVs) are small vesicles ranging from 20–200 nm to 10 μm in diameter that are discharged and taken in by many different types of cells. Depending on the nature and quantity of their content—which generally includes proteins, lipids as well as microRNAs (miRNAs), messenger-RNA (mRNA), and DNA—these particles can bring about functional modifications in the receiving cells. During pregnancy, placenta and/or fetal-derived EVs have recently been isolated, eliciting interest in discovering their clinical significance. To date, various studies have associated variations in the circulating levels of maternal and fetal EVs and their contents, with complications including gestational diabetes and preeclampsia, ultimately leading to adverse pregnancy outcomes. Furthermore, EVs have also been identified as messengers and important players in viral infections during pregnancy, as well as in various congenital malformations. Their presence can be detected in the maternal blood from the first trimester and their level increases towards term, thus acting as liquid biopsies that give invaluable insight into the status of the feto-placental unit. However, their exact roles in the metabolic and vascular adaptations associated with physiological and pathological pregnancy is still under investigation. Analyzing peer-reviewed journal articles available in online databases, the purpose of this review is to synthesize current knowledge regarding the utility of quantification of pregnancy related EVs in general and placental EVs in particular as non-invasive evidence of placental dysfunction and adverse pregnancy outcomes, and to develop the current understanding of these particles and their applicability in clinical practice. 相似文献
193.
The rheological behaviour of aqueous solutions of two commercial anionic hydrophobically modified alkali-swellable emulsions (HASE), Acrysol TT615 and RM5, was studied. These polymeric systems, initially in the form of low-viscosity latices at low pH, tend to swell and increase their viscosity when neutralised with base. The steady-shear and dynamic properties of these polymers were measured over a wide range of concentration, at constant pH=9 and temperature of 20°C. The intrinsic and zero-shear viscosities were used to identify the concentration regimes of the polymer solutions. In the case of Acrysol TT615, the solution exhibited shear-thinning characteristics at a concentration above 500 ppm. The Carreau model described well the viscosity function of the 1000 and 2000 ppm solutions. Considerable viscosity enhancement and a change in the flow curve profile were observed at concentrations above 2000 ppm. At high polymer concentration. the zero-shear viscosity was not detectable, and the power law model was adequate to characterize these solutions. By contrast, the RM5 solutions exhibited nearly Newtonian behaviour over the whole concentration range considered. Elasticity measured from the first normal stress difference indicated that Acrysol TT615 was more elastic than Acrysol RM5. Dynamic measurements revealed that both storage (G′) and loss (G″) moduli increased with polymer concentration. In the higher frequency and concentration regions, G′ > G″ was obseved for TT615, whereas G″ > G′ for RM5. 相似文献
194.
Nicolae Enaki 《Journal of Low Temperature Physics》2010,160(5-6):157-178
The behavior of an electronic subsystem in strong interaction with phonon subsystem, or quantified electromagnetic field (QEF) is discussed. In this case the correlation effect between first and second order electron–phonon interaction (or atom–QEF interaction) takes place. It is shown that the temperature dependence of two-quanta exchange between Fermi sub-system and thermal reservoir gives a non-linear behavior of the order parameter in superconductivity and super-radiance, accompanied by an increase of the electron correlations with increasing temperature. The same effect is considered for two-quanta scattering processes, in which one quantum is absorbed and another is emitted. It is demonstrated, that the order parameter in such a system firstly increases with temperature achieving the maximal value. After that it decreases as in traditional phase transition effects. 相似文献
195.
Surface properties,thermal, and mechanical characteristics of poly(vinyl alcohol)–starch‐bacterial cellulose composite films 下载免费PDF全文
Ioana Chiulan Adriana Nicoleta Frone Denis Mihaela Panaitescu Cristian Andi Nicolae Roxana Trusca 《应用聚合物科学杂志》2018,135(6)
Nanocomposite films for food packaging applications were developed using bacterial cellulose (BC) nanofibers in different amount in a poly(vinyl alcohol)/starch (PVA/St) matrix. In search of a better method to reduce the harmful ingredients in food packaging, the cellulose nanofibers were obtained by the mechanical defibrillation of BC pellicles thus avoiding the addition of chemicals in the final packaging material. Improved mechanical performances were obtained starting from just 1% BC nanofibers in PVA/St. Atomic force microscopy images showed a uniform dispersion of BC nanofibers on the surface of nanocomposites. A twofold increase of both tensile strength and modulus was obtained for 2 wt % BC in the composite. BC nanofibers have greatly improved the barrier properties of PVA/St matrix, a twofold increase of water vapor permeability being obtained for only 2 wt % BC nanofibers in the composite film. PVA/St/2BC was proposed as a high potential material for food packaging applications. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45800. 相似文献