全文获取类型
收费全文 | 754篇 |
免费 | 53篇 |
出版年
2022年 | 7篇 |
2021年 | 12篇 |
2020年 | 7篇 |
2018年 | 10篇 |
2017年 | 8篇 |
2016年 | 14篇 |
2015年 | 21篇 |
2014年 | 20篇 |
2013年 | 38篇 |
2012年 | 50篇 |
2011年 | 47篇 |
2010年 | 27篇 |
2009年 | 27篇 |
2008年 | 32篇 |
2007年 | 36篇 |
2006年 | 31篇 |
2005年 | 24篇 |
2004年 | 36篇 |
2003年 | 31篇 |
2002年 | 22篇 |
2001年 | 31篇 |
2000年 | 24篇 |
1999年 | 19篇 |
1998年 | 8篇 |
1996年 | 10篇 |
1995年 | 7篇 |
1994年 | 10篇 |
1993年 | 4篇 |
1992年 | 15篇 |
1991年 | 17篇 |
1990年 | 5篇 |
1989年 | 9篇 |
1988年 | 14篇 |
1987年 | 9篇 |
1986年 | 11篇 |
1985年 | 10篇 |
1984年 | 5篇 |
1983年 | 8篇 |
1981年 | 5篇 |
1980年 | 7篇 |
1978年 | 6篇 |
1977年 | 11篇 |
1976年 | 5篇 |
1975年 | 6篇 |
1974年 | 7篇 |
1973年 | 5篇 |
1972年 | 8篇 |
1971年 | 4篇 |
1970年 | 6篇 |
1969年 | 4篇 |
排序方式: 共有807条查询结果,搜索用时 218 毫秒
91.
Kumar R Ramachandran U Khanna S Bharatam PV Raichur S Chakrabarti R 《Bioorganic & medicinal chemistry》2007,15(3):1547-1555
A novel series of l-tyrosine derivatives have been reported with potential PPARalpha/gamma dual agonistic activity. In vitro cell based PPARalpha/gamma transactivation studies have shown compound 4a and compound 4f to be the most potent PPARgamma and PPARalpha activators, respectively. Molecular docking studies performed on these series of compounds have complemented the experimental results and have led to interesting inferences. 相似文献
92.
93.
Trager EH Khanna R Marrs A Siden L Branham KE Swaroop A Richards JE 《Bioinformatics (Oxford, England)》2007,23(14):1854-1856
The Madeline 2.0 Pedigree Drawing Engine (PDE) is a pedigree drawing program for use in linkage and family-based association studies. The program is designed to handle large and complex pedigrees with an emphasis on readability and aesthetics. For complex pedigrees, we use a hybrid algorithm in which consanguinous loops are drawn as cyclic graphs whenever possible, but we resort to acyclic graphs when matings can no longer be connected without line crossings. A similar hybrid approach is used to avoid line crossings for matings between distant descendants of different founding groups. Written in object-oriented C++ and released under the GNU General Public License (GPL), Madeline 2.0 PDE reads input files specified on the command line and generates pedigree drawings without user interaction. Pedigree output in scalable vector graphics (SVG) format can be viewed in browsers with native SVG rendering support or in vector graphics editors. We provide an easy-to-use public web service, which is experimental and still under development. Availability: http://kellogg.umich.edu/madeline. 相似文献
94.
Kumar Khanna V 《Biotechnology advances》2007,25(1):85-98
The current status and research trends of detection techniques for DNA-based analysis such as DNA finger printing, sequencing, biochips and allied fields are examined. An overview of main detectors is presented vis-à-vis these DNA operations. The biochip method is explained, the role of micro- and nanoelectronic technologies in biochip realization is highlighted, various optical and electrical detection principles employed in biochips are indicated, and the operational mechanisms of these detection devices are described. Although a diversity of biochips for diagnostic and therapeutic applications has been demonstrated in research laboratories worldwide, only some of these chips have entered the clinical market, and more chips are awaiting commercialization. The necessity of tagging is eliminated in refractive-index change based devices, but the basic flaw of indirect nature of most detection methodologies can only be overcome by generic and/or reagentless DNA sensors such as the conductance-based approach and the DNA-single electron transistor (DNA-SET) structure. Devices of the electrical detection-based category are expected to pave the pathway for the next-generation DNA chips. The review provides a comprehensive coverage of the detection technologies for DNA finger printing, sequencing and related techniques, encompassing a variety of methods from the primitive art to the state-of-the-art scenario as well as promising methods for the future. 相似文献
95.
Pai S O'Sullivan B Abdul-Jabbar I Peng J Connoly G Khanna R Thomas R 《Immunology and cell biology》2007,85(5):370-377
Sequence variation in the Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) oncogene structure may affect antigen-presenting cell (APC) function of infected B cells and immune escape by EBV-specific T cells and thus contribute to the development of malignancy. Normal B cell-associated LMP1 (B-LMP1) upregulates B cell APC function through activation of the necrosis factor (NF)-kappaB subunit, RelB. We examined the ability of B-LMP1 and a nasopharyngeal carcinoma-associated LMP1 (NPC-LMP1) to modulate B cell APC function and T-cell responses. B lymphoma cells transfected with NPC-LMP1 stimulated resting T cells in mixed lymphocyte reaction less efficiently than B-LMP1 transfectants. Unexpectedly, antigen presentation to CD4(+) T helper cells was reduced owing to potentiation of regulatory T-cell function by NPC-LMP1 transfectants, which produce increased levels of interleukin-10, rendering CD4(+) T cells hyporesponsive. Thus, after primary EBV infection, T cells may escape activation by NPC-LMP1. These observations have important implications for the establishment of EBV-associated malignancy in the context of infection with tumour-associated EBV LMP1 variants. 相似文献
96.
Saima Khanam Pilankatta Rajendra Navin Khanna Sathyamangalam Swaminathan 《BMC biotechnology》2007,7(1):10
Background
Dengue is a public health problem of global significance for which there is neither an effective antiviral therapy nor a preventive vaccine. It is a mosquito-borne viral disease, caused by dengue (DEN) viruses, which are members of the Flaviviridae family. There are four closely related serotypes, DEN-1, DEN-2, DEN-3 and DEN-4, each of which is capable of causing disease. As immunity to any one serotype can potentially sensitize an individual to severe disease during exposure to a heterologous serotype, the general consensus is that an effective vaccine should be tetravalent, that is, it must be capable of affording protection against all four serotypes. The current strategy of creating tetravalent vaccine formulations by mixing together four monovalent live attenuated vaccine viruses has revealed the phenomenon of viral interference leading to the manifestation of immune responses biased towards a single serotype. 相似文献97.
Thein M Cheng A Khanna P Zhang C Park EJ Ahmed D Goodrich CJ Asphahani F Wu F Smith NB Dong C Jiang X Zhang M Xu J 《Biosensors & bioelectronics》2011,27(1):25-33
We developed a new instrumental method by which human melanoma cells (LU1205) are sonoporated via radiation pressures exerted by highly-confined ultrasonic waves produced by high lateral-resolution ultrasonic micro-transducer arrays (UMTAs). The method enables cellular-level site-specific sonoporation within the cell monolayer due to UMTAs and can be applicable in the delivery of drugs and gene products in cellular assays. In this method, cells are seeded on the biochip that employs UMTAs for high spatial resolution and specificity. UMTAs are driven by 30-MHz sinusoidal signals and the resulting radiation pressures induce sonoporation in the targeted cells. The sonoporation degree and the effective lateral resolution of UMTAs are determined by performing fluorescent microscopy and analysis of carboxylic-acid-derivatized CdSe/ZnS quantum dots passively transported into the cells. Models representing the transducer-generated ultrasound radiation pressure, the ultrasound-inflicted cell membrane wound, and the transmembrane transport through the wound are developed to determine the ultrasound-pressure-dependent wound size and enhanced cellular uptake of nanoparticles. Model-based calculations show that the effective wound size and cellular uptake of nanoparticles increase linearly with increasing ultrasound pressure (i.e., at applied radiation pressures of 0.21, 0.29, and 0.40 MPa, the ultrasound-induced initial effective wound radii are 150, 460, and 650 nm, respectively, and the post-sonoporation intracellular quantum-dot concentrations are 7.8, 22.8, and 29.9 nM, respectively) and the threshold pressure required to induce sonoporation in LU1205 cells is ~0.12 MPa. 相似文献
98.
Brittain JM Duarte DB Wilson SM Zhu W Ballard C Johnson PL Liu N Xiong W Ripsch MS Wang Y Fehrenbacher JC Fitz SD Khanna M Park CK Schmutzler BS Cheon BM Due MR Brustovetsky T Ashpole NM Hudmon A Meroueh SO Hingtgen CM Brustovetsky N Ji RR Hurley JH Jin X Shekhar A Xu XM Oxford GS Vasko MR White FA Khanna R 《Nature medicine》2011,17(7):822-829
99.
100.
Michelle L North Hajera Amatullah Nivedita Khanna Bruce Urch Hartmut Grasemann Frances Silverman Jeremy A Scott 《Respiratory research》2011,12(1):19