全文获取类型
收费全文 | 46806篇 |
免费 | 4192篇 |
国内免费 | 1232篇 |
出版年
2023年 | 667篇 |
2022年 | 657篇 |
2021年 | 1120篇 |
2020年 | 1649篇 |
2019年 | 2151篇 |
2018年 | 1928篇 |
2017年 | 1345篇 |
2016年 | 1314篇 |
2015年 | 1504篇 |
2014年 | 2898篇 |
2013年 | 3380篇 |
2012年 | 2170篇 |
2011年 | 2833篇 |
2010年 | 2108篇 |
2009年 | 2354篇 |
2008年 | 2548篇 |
2007年 | 2466篇 |
2006年 | 2067篇 |
2005年 | 1900篇 |
2004年 | 1693篇 |
2003年 | 1439篇 |
2002年 | 1256篇 |
2001年 | 856篇 |
2000年 | 657篇 |
1999年 | 663篇 |
1998年 | 538篇 |
1997年 | 444篇 |
1996年 | 439篇 |
1995年 | 536篇 |
1994年 | 533篇 |
1993年 | 427篇 |
1992年 | 389篇 |
1991年 | 348篇 |
1990年 | 270篇 |
1989年 | 252篇 |
1988年 | 210篇 |
1987年 | 225篇 |
1986年 | 169篇 |
1985年 | 324篇 |
1984年 | 455篇 |
1983年 | 401篇 |
1982年 | 420篇 |
1981年 | 344篇 |
1980年 | 350篇 |
1979年 | 274篇 |
1978年 | 218篇 |
1977年 | 210篇 |
1976年 | 210篇 |
1975年 | 179篇 |
1974年 | 165篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
LncRNA MALAT1 is dysregulated in diabetic nephropathy and involved in high glucose‐induced podocyte injury via its interplay with β‐catenin 下载免费PDF全文
4.
Atomic Layer Deposition of Functional Layers for on Chip 3D Li‐Ion All Solid State Microbattery 下载免费PDF全文
Manon Létiche Etienne Eustache Jeremy Freixas Arnaud Demortière Vincent De Andrade Laurence Morgenroth Pascal Tilmant François Vaurette David Troadec Pascal Roussel Thierry Brousse Christophe Lethien 《Liver Transplantation》2017,7(2)
Nowadays, millimeter scale power sources are key devices for providing autonomy to smart, connected, and miniaturized sensors. However, until now, planar solid state microbatteries do not yet exhibit a sufficient surface energy density. In that context, architectured 3D microbatteries appear therefore to be a good solution to improve the material mass loading while keeping small the footprint area. Beside the design itself of the 3D microbaterry, one important technological barrier to address is the conformal deposition of thin films (lithiated or not) on 3D structures. For that purpose, atomic layer deposition (ALD) technology is a powerful technique that enables conformal coatings of thin film on complex substrate. An original, robust, and highly efficient 3D scaffold is proposed to significantly improve the geometrical surface of miniaturized 3D microbattery. Four functional layers composing the 3D lithium ion microbattery stacking has been successfully deposited on simple and double microtubes 3D templates. In depth synchrotron X‐ray nanotomography and high angle annular dark field transmission electron microscope analyses are used to study the interface between each layer. For the first time, using ALD, anatase TiO2 negative electrode is coated on 3D tubes with Li3PO4 lithium phosphate as electrolyte, opening the way to all solid‐state 3D microbatteries. The surface capacity is significantly increased by the proposed topology (high area enlargement factor – “thick” 3D layer), from 3.5 μA h cm?2 for a planar layer up to 0.37 mA h cm?2 for a 3D thin film (105 times higher). 相似文献
5.
A series of color‐tunable Ca3–2x‐y‐zSiO4Cl2 (CSC):xCe3+,xLi+,yMn2+,zEu2+ phosphors with low temperature phase structure was synthesized via the sol–gel method. An energy transfer process from Ce3+ to Mn2+ in CSC:0.01Ce3+,0.01Li+,yMn2+ (y = 0.03–0.09) and the mechanism was verified to be an electric dipole–dipole interaction. The Ce3+ and Mn2+ emission intensities were greatly enhanced by co‐doping Eu2+ ions into CSC:0.01Ce3+,0.01Li+,0.07Mn2+ phosphors due to competitive energy transfers from Eu2+/Ce3+ to Mn2+, and Ce3+ to Eu2+. Under 332 nm excitation, CSC:0.01Ce3+,0.01Li+,0.07Mn2+,zEu2+ (z = 0.0005–0.002) exhibited tunable emission colors from green to white with coexisting orange, green and violet‐blue emissions. These phosphors could have potential application in white light‐emitting diodes. 相似文献
6.
Spectroscopic and in silico study of binding mechanism of cynidine‐3‐O‐glucoside with human serum albumin and glycated human serum albumin 下载免费PDF全文
The drug–serum albumin interaction plays a dominant role in drug efficacy and disposition. The glycation of serum albumin that occurs during diabetes may affect its drug‐binding properties in vivo. In order to evaluate the interactivity characteristics of cyanidin‐3‐O‐glucoside (C3G) with human serum albumin (HSA) and glycated human serum albumin (gHSA), this study was undertaken using multiple spectroscopic techniques and molecular modeling analysis. Time‐resolved fluorescence and the thermodynamic parameters indicated that the quenching mechanism was static quenching, and hydrogen bonding and Van der Waals force were the main forces. The protein fluorescence could be quenched by C3G, whereas the polarity of the fluorophore was not obviously changed. C3G significantly altered the secondary structure of the proteins. Furthermore, the interaction force that existed in the HSA–C3G system was greater than that in the gHSA–C3G system. Fluorescence excitation emission matrix spectra, red edge excitation shift, Fourier transform infrared spectroscopy and circular dichroism spectra provided further evidence that glycation could inhibit the binding between C3G and proteins. In addition, molecular modeling analysis supported the experimental results. The results provided more details for the application of C3G in the treatment of diabetes. 相似文献
7.
8.
9.
L. Crispoltoni S. Porcellati A. M. Del Pino A. Orlacchio G. Coata S. Arnone E. Torlone B. Cappuccini G. C. Di Renzo A. Orlacchio 《Cell biochemistry and function》2014,32(1):87-95
Several epidemiological studies showed that gestational diabetes mellitus is the most frequent metabolic disorder of pregnancy, the pathogenesis of which has yet to be completely clarified. The aim of this study was to investigate the presence and processing of caspase 3 (Casp3) and poly(ADP‐ribose) polymerase 1 (PARP1) in cord blood lymphocytes as markers of apoptosis in relation to glycaemic control during intrauterine life. Our results showed a specific positive correlation between the levels of active Casp3 (17–19 kDa) and the inactive form of PARP1 (89 kDa) in lymphocytes isolated from newborn babies of diabetic women with unbalanced glycaemic control, with a direct correlation between the activation of casp3 and the inactivation of PARP1, that makes lymphocytes unresponsive towards lipopolysaccharide stimulation, highlighting an altered functional response. Besides more studies are required to fully correlate the activation of the apoptotic process during the intrauterine life with the foetal health later in life, our study indicates that a cord blood lymphocyte, an easily accessible source, is informative about the activation of apoptotic stimuli in circulating cells of newborn babies in relation to the glycaemic control reached by the mother during pregnancy. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
10.
The actin cortex is a thin layer of actin, myosin and actin-binding proteins that underlies the membrane of most animal cells. It is highly dynamic and can undergo remodelling on timescales of tens of seconds, thanks to protein turnover and myosin-mediated contractions. The cortex enables cells to resist external mechanical stresses, controls cell shape and allows cells to exert forces on their neighbours. Thus, its mechanical properties are the key to its physiological function. Here, we give an overview of how cortex composition, structure and dynamics control cortex mechanics and cell shape. We use mitosis as an example to illustrate how global and local regulation of cortex mechanics gives rise to a complex series of cell shape changes. 相似文献