全文获取类型
收费全文 | 1852篇 |
免费 | 138篇 |
国内免费 | 2篇 |
出版年
2023年 | 10篇 |
2022年 | 11篇 |
2021年 | 52篇 |
2020年 | 33篇 |
2019年 | 23篇 |
2018年 | 45篇 |
2017年 | 39篇 |
2016年 | 48篇 |
2015年 | 75篇 |
2014年 | 87篇 |
2013年 | 115篇 |
2012年 | 144篇 |
2011年 | 130篇 |
2010年 | 68篇 |
2009年 | 56篇 |
2008年 | 94篇 |
2007年 | 65篇 |
2006年 | 72篇 |
2005年 | 65篇 |
2004年 | 57篇 |
2003年 | 63篇 |
2002年 | 41篇 |
2001年 | 39篇 |
2000年 | 32篇 |
1999年 | 25篇 |
1998年 | 14篇 |
1997年 | 17篇 |
1995年 | 10篇 |
1994年 | 13篇 |
1992年 | 36篇 |
1991年 | 24篇 |
1990年 | 23篇 |
1989年 | 22篇 |
1988年 | 15篇 |
1987年 | 23篇 |
1986年 | 13篇 |
1985年 | 24篇 |
1984年 | 29篇 |
1983年 | 17篇 |
1982年 | 17篇 |
1981年 | 18篇 |
1979年 | 24篇 |
1978年 | 14篇 |
1977年 | 13篇 |
1975年 | 12篇 |
1974年 | 14篇 |
1973年 | 10篇 |
1969年 | 13篇 |
1968年 | 10篇 |
1966年 | 10篇 |
排序方式: 共有1992条查询结果,搜索用时 218 毫秒
71.
Aparna Sarkar Dinesh Kumar Pyne Tuyan Biswas Rumpa Das Gandhi K. Kar Arnab Halder 《Luminescence》2020,35(5):709-720
The synthesis is described of a luminescent furophenanthraquinone derivative, 9‐methoxyphenanthro[4,3‐b]furan‐4,5‐dione (MPFD). The biological importance of tetracyclic furophenanthraquinones was considered and the tunable luminescence of MPFD in different solvents was studied to explore the nature of the specific interactions between MPFD and solvents. Observation of dual emission bands and identical nature of the fluorescence excitation spectra of MPFD monitored at the emission wavelength in polar solvents indicated the formation of two different types of species in the excited state, probably due to proton transfer from the solvent to MPFD. Luminescence intensity due to anionic species was found to be increased and the corresponding peak was red shifted with increase in the proton‐donating ability of the solvents, acting as an acid with respect to MPFD. Availability of more acidic protons in the solvent facilitated this phenomenon occurring in the excited state. MPFD also interacted with halogen‐containing solvents by forming electron donor–acceptor charge transfer (CT) complexes. This CT complex formation was dependent on the number of chlorine atoms; the position of the corresponding luminescence band varied with the polarity of the solvent. Extent of the CT increased with increase in the number of chlorine atoms in the dichloro, trichloro and tetrachloro solvents, whereas the luminescence peak due to the CT complex was found to be blue shifted with decrease in solvent polarity. Interaction of the synthesized bioactive MPFD with different solvents deserves biological importance as proton transfer and CT play pivotal roles in biology. 相似文献
72.
73.
74.
Kumar Ritesh Khungar Lisha Shimphrui Rinchuila Tiwari Lalit Dev Tripathi Gayatri Sarkar Neelam K. Agarwal Surekha-Katiyar Agarwal Manu Grover Anil 《Journal of plant biochemistry and biotechnology.》2020,29(4):715-732
Journal of Plant Biochemistry and Biotechnology - Caseinolytic protease (Clp)/Hsp100 proteins are members of the AAA+ (ATPase associated with a variety of cellular activities) family of proteins... 相似文献
75.
Shrivastava Vineeta Savarimuthu Arockiasamy Patil Manoj Sarkar Purbasha Hadole Sainath Dasgupta Santanu 《Plant Cell, Tissue and Organ Culture》2021,144(2):359-370
Plant Cell, Tissue and Organ Culture (PCTOC) - Jatropha curcas is an undomesticated crop and its plantations did not meet commercial expectation due to absence of high yielding commercial line with... 相似文献
76.
Sarkar Monaj Kumar Kar Amrita Jayaraman Adithyan Shanmugam Karthi Vadivel Vellingiri Mahapatra Santanu Kar 《Molecular biology reports》2021,48(6):5327-5334
Molecular Biology Reports - Myricitrin, a naturally occurring flavonoid in Madhuca longifolia, possesses several medicinal properties. Even though our earlier work revealed its role against the... 相似文献
77.
Chettri Dixita Verma Ashwani Kumar Sarkar Lija Verma Anil Kumar 《Extremophiles : life under extreme conditions》2021,25(3):203-219
Extremophiles - Technological advances in the field of life sciences have led to discovery of organisms that live in harsh environmental conditions referred to as extremophiles. These organisms... 相似文献
78.
Debashis Roy Gautam Chakraborty Abhisek Biswas Pijush Kanti Sarkar 《Journal of Asia》2021,24(1):448-460
Twenty-six rice landraces from West Bengal, India were evaluated for antixenosis and tolerance against brown planthopper (BPH) biotype 4 at the Bidhan Chandra Krishi Viswavidyalaya (BCKV), West Bengal. High levels of resistance were observed in six landraces, namely Badshabhog, Gamra, Haldichuri, Janglijata, Kalabhat and Khara. These phenotypically resistant rice landraces including Ptb33 exhibited lowest feeding rate, fecundity, nymphal and adult preference, survival, plant dry weight loss per mg of BPH dry weight produced (PDWL), and higher functional plant loss index (FPLI), more days to wilt and unhatched eggs compared with the susceptible check Swarna. All the landraces were classified into four major clusters at 10 unit distance by the scale of similarity during genetic diversity analysis through 21 gene-linked SSR markers of BPH resistance. Some phenotypically resistant landraces were gathered under the major cluster I indicating their analogous genetic history, while some were grouped with susceptible landraces exhibiting their genetic variation. The resistant landraces can be used as potential donors in the breeding programme for the development of rice varieties with resistance to BPH. 相似文献
79.
Takahashi Yumiko Sarkar Juli Yamada Jumpei Matsunaga Yutaka Nonaka Yudai Banjo Mai Sakaguchi Ryo Shinya Terunaga Hatta Hideo 《Journal of physiology and biochemistry》2021,77(3):469-480
Journal of Physiology and Biochemistry - To identify factors that influence post-exercise muscle glycogen repletion, we compared the glycogen recovery after level running with downhill running, an... 相似文献
80.
Oindrila Raha Biswanath Sarkar Bhaskar VKS Lakkakula Veerraju Pasumarthy Sudhakar Godi Subhankar Chowdhury Pradip Raychaudhuri Raghavendra Rao Vadlamudi 《Journal of biomedical science》2013,20(1):12