全文获取类型
收费全文 | 310篇 |
免费 | 21篇 |
出版年
2022年 | 5篇 |
2021年 | 5篇 |
2019年 | 2篇 |
2018年 | 7篇 |
2016年 | 8篇 |
2015年 | 13篇 |
2014年 | 21篇 |
2013年 | 23篇 |
2012年 | 20篇 |
2011年 | 17篇 |
2010年 | 10篇 |
2009年 | 9篇 |
2008年 | 17篇 |
2007年 | 5篇 |
2006年 | 9篇 |
2005年 | 8篇 |
2004年 | 6篇 |
2003年 | 6篇 |
2002年 | 10篇 |
2001年 | 5篇 |
2000年 | 5篇 |
1999年 | 5篇 |
1998年 | 8篇 |
1997年 | 4篇 |
1996年 | 5篇 |
1995年 | 1篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1991年 | 5篇 |
1990年 | 5篇 |
1989年 | 9篇 |
1988年 | 7篇 |
1987年 | 6篇 |
1986年 | 1篇 |
1985年 | 5篇 |
1984年 | 5篇 |
1983年 | 9篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 5篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 4篇 |
1974年 | 9篇 |
1973年 | 1篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有331条查询结果,搜索用时 15 毫秒
11.
12.
13.
Theanne Schiros Gregor Kladnik Deborah Prezzi Andrea Ferretti Giorgia Olivieri Albano Cossaro Luca Floreano Alberto Verdini Christine Schenck Marshall Cox Alon A. Gorodetsky Kyle Plunkett Dean Delongchamp Colin Nuckolls Alberto Morgante Dean Cvetko Ioannis Kymissis 《Liver Transplantation》2013,3(7):894-902
While the demonstrated power conversion efficiency of organic photovoltaics (OPVs) now exceeds 10%, new design rules are required to tailor interfaces at the molecular level for optimal exciton dissociation and charge transport in higher efficiency devices. We show that molecular shape‐complementarity between donors and acceptors can drive performance in OPV devices. Using core hole clock (CHC) X‐ray spectroscopy and density functional theory (DFT), we compare the electronic coupling, assembly, and charge transfer rates at the interface between C60 acceptors and flat‐ or contorted‐hexabenzocorone (HBC) donors. The HBC donors have similar optoelectronic properties but differ in molecular contortion and shape matching to the fullerene acceptors. We show that shape‐complementarity drives self‐assembly of an intermixed morphology with a donor/acceptor (D/A) ball‐and‐socket interface, which enables faster electron transfer from HBC to C60. The supramolecular assembly and faster electron transfer rates in the shape complementary heterojunction lead to a larger active volume and enhanced exciton dissociation rate. This work provides fundamental mechanistic insights on the improved efficiency of organic photovoltaic devices that incorporate these concave/convex D/A materials. 相似文献
14.
Francesca Ripamonti Luisa Albano Anna Rossini Serena Borrelli Sonia Fabris Roberto Mantovani Antonino Neri Andrea Balsari Alessandra Magnifico Elda Tagliabue 《Journal of cellular physiology》2013,228(4):871-878
Many squamous cell carcinomas (SCCs) are characterized by high levels of EGFR and by overexpression of the ΔNp63α isoform. Here, we investigated the regulation of ΔNp63α expression upon EGFR activation and the role of the EGFR–ΔNp63α axis in proliferation of SCC tumor‐initiating cells (TICs). SCC cell lines A‐431, Cal‐27, and SCC‐25 treated with EGF showed a time‐dependent increase in ΔNp63α expression at the protein and mRNA levels, which was blocked by the tyrosine kinase inhibitor (TKI) Lapatinib. RNA interference experiments suggested the role of STAT3 in regulating ΔNp63α expression downstream of EGFR. Inactivation of EGFR by the monoclonal antibody Cetuximab and RNA interference against STAT3 or ΔNp63α impaired the TICs ability to grow under non‐differentiating conditions. Radiation treatment, which triggers EGFR activation, induced ΔNp63α accumulation without affecting TICs proliferation, whereas the combination Cetuximab plus radiation significantly reduced TICs growth under non‐differentiating conditions. Together, our findings provide evidence that ΔNp63α expression is regulated by EGFR activation through STAT3 and that the EGFR–ΔNp63α axis is crucial for proliferation of TICs present in SCCs. J. Cell. Physiol. 228: 871–878, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
15.
16.
C García-Vielma MI Dávila-Rodríguez F Hernández-Garza RM Cerda-Flores 《Biotechnic & histochemistry》2016,91(2):102-107
We performed a hospital-based, unmatched case-control study to investigate the association between progressive stages of cervical neoplasia and digital analysis of cell proliferation by silver stained nucleolus organizer region associated proteins (AgNORs). We measured cell proliferation levels in the cervical epithelial cells of 10 women with low grade squamous intraepithelial lesions (LG-SIL), eight with high grade squamous intraepithelial lesions (HG-SIL), 11 with cervical cancer (CC) and eight with no cervical lesions (controls) using the AgNORs technique. Cell proliferation was measured by digital image analysis (DIA). DIA revealed increased total areas of AgNORs in HG-SIL and CC compared to LG-SIL and control patients. AgNORs with a kidney or cluster shape exhibited greater areas than those with a spherical or long shape. We propose a cut-off of 118 pixels to differentiate benign (control and LG-SIL) from malignant (HG-SIL and CC) lesions. DIA of AgNORs is a simple and inexpensive method for studying proliferation. The increased total area of AgNORs in malignant lesions provides information regarding cell behavior and may be related to cervical carcinogenesis; however, further validation studies are required to establish its usefulness in cytological analysis. 相似文献
17.
Giulia Schiroli Anastasia Conti Samuele Ferrari Lucrezia della Volpe Aurelien Jacob Luisa Albano Stefano Beretta Andrea Calabria Valentina Vavassori Patrizia Gasparini Eralda Salataj Delphine Ndiaye-Lobry Chiara Brombin Julie Chaumeil Eugenio Montini Ivan Merelli Pietro Genovese Luigi Naldini Raffaella Di Micco 《Cell Stem Cell》2019,24(4):551-565.e8
18.
Brandi G Sisti M Giardini F Schiavano GF Albano A 《Letters in applied microbiology》1999,29(4):211-215
The ability of motile Aeromonas spp. to survive in drinking water (mineral and tap water) and in sea water was experimentally tested. Clinically isolated cytotoxic strains of A. hydrophila, A. caviae and A. sobria were selected for this study. After contamination of water samples, the survival of Aeromonas strains was studied for at least three months using viable counts. The results obtained show that the survival of the Aeromonas spp. varies considerably depending on species and water type. For all three species, the survival time was longest in mineral water, where viable bacteria of each strain were still detected after 100 d. Moreover, A hydrophila and A. caviae also re-grew on the first day. In tap water all strains showed marked survival, although to a lesser extent than in mineral water. Aeromonas cells showed a rapid decline in sea water (90% reduction in viable cells after about two d) and thus seem to be more sensitive to saline/marine stress than chlorination. 相似文献
19.
20.
Gellan gum biosynthesis in Sphingomonas paucimobilis ATCC 31461: genes,enzymes and exopolysaccharide production engineering 总被引:2,自引:0,他引:2
Sá-Correia I Fialho AM Videira P Moreira LM Marques AR Albano H 《Journal of industrial microbiology & biotechnology》2002,29(4):170-176
The commercial gelling agent, gellan, is an extracellular polysaccharide (EPS) produced by Sphingomonas paucimobilis ATCC 31461. In recent years, significant progress in understanding the relationship between gellan structure and properties
and elucidation of the biosynthesis and engineering of this recent product of biotechnology has been made. This review focuses
on recent advances in this field. Emphasis is given to identification and characterization of genes and enzymes involved,
or predicted to be involved, in the gellan biosynthetic pathway, at the level of synthesis of sugar-activated precursors,
of the repeat unit assembly and of gellan polymerization and export. Identification of several genes, biochemical characterization
of the encoded enzymes and elucidation of crucial steps of the gellan pathway indicate that possibilities now exist for exerting
control over gellan production at any of the three levels of its biosynthesis. However, a better knowledge of the poorly understood
steps and of the bottlenecks and regulation of the pathway, the characterization of the composition, structure and functional
properties of gellan-like polymers produced either by the industrial strain under different culture conditions or by mutants
are still required for eventual success of the metabolic engineering of gellan production. Journal of Industrial Microbiology & Biotechnology (2002) 29, 170–176 doi:10.1038/sj.jim.7000266
Received 11 February 2002/ Accepted in revised form 09 April 2002 相似文献