全文获取类型
收费全文 | 348篇 |
免费 | 27篇 |
国内免费 | 1篇 |
专业分类
376篇 |
出版年
2024年 | 1篇 |
2023年 | 1篇 |
2022年 | 5篇 |
2021年 | 9篇 |
2020年 | 6篇 |
2019年 | 3篇 |
2018年 | 16篇 |
2017年 | 7篇 |
2016年 | 19篇 |
2015年 | 20篇 |
2014年 | 21篇 |
2013年 | 27篇 |
2012年 | 28篇 |
2011年 | 32篇 |
2010年 | 23篇 |
2009年 | 13篇 |
2008年 | 26篇 |
2007年 | 13篇 |
2006年 | 8篇 |
2005年 | 16篇 |
2004年 | 8篇 |
2003年 | 12篇 |
2002年 | 7篇 |
2001年 | 6篇 |
2000年 | 8篇 |
1999年 | 4篇 |
1998年 | 9篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有376条查询结果,搜索用时 15 毫秒
61.
Jasmonic acid induced changes in protein pattern, antioxidative enzyme activities and peroxidase isozymes in peanut seedlings 总被引:1,自引:0,他引:1
G. J. Kumari A. M. Reddy S. T. Naik S. G. Kumar J. Prasanthi G. Sriranganayakulu P. C. Reddy Chinta Sudhakar 《Biologia Plantarum》2006,50(2):219-226
Protein pattern, ammonia content, glutamine synthetase activity, lipid peroxidation, superoxide dismutase, catalase, peroxidase
and peroxidase isoforms were studied in the leaves and roots of 7-d-old peanut (Arachis hypogaea L. cv. JL-24) seedlings treated by 25, 100 and 250 μM jasmonic acid (JA). SDS-PAGE protein profile of leaves and roots after
JA application showed a significant increase in 18, 21, 30, 45, 47 and 97.4 kDa proteins and significant decrease in 22 and
36 kDa proteins. Pathogenesis related PR-18 was specific in leaves at 250 μM JA and PR-21 have cross reacted differently with
21 and 30 kDa proteins in leaves and roots treated by all JA concentrations. Further, the immunoblot analysis with glutamine
synthetase, GS-45 antibodies revealed a specific cross reaction with 45 and 47 kDa proteins of both control and JA treated
leaves, however, higher at 100 and 250 μM JA treated leaves than control ones. Further, the malondialdehyde (MDA) content
significantly increased in leaves and roots treated with JA, indicated membrane damage with JA treatments that led to the
generation of peroxidation products. The peroxidase isozymic pattern showed two specific isoforms. Besides, the activities
of SOD and catalase were significantly elevated in JA treated leaves. 相似文献
62.
Sudhakar Baluchamy Ye Zhang Prabakaran Ravichandran Vani Ramesh Ayodotun Sodipe Joseph C. Hall Olufisayo Jejelowo Daila S. Gridley Honglu Wu Govindarajan T. Ramesh 《Molecular and cellular biochemistry》2010,341(1-2):207-215
Exposure of living systems to radiation results in a wide assortment of lesions, the most significant of is damage to genomic DNA which alter specific cell functions including cell proliferation. The radiation induced DNA damage investigation is one of the important area in biology, but still the information available regarding the effects of proton is very limited. In this report, we investigated the differential gene expression pattern of DNA damage signaling genes such as damaged DNA binding, repair, cell cycle arrest, checkpoints and apoptosis using quantitative real-time RT-PCR in proton exposed mouse brain tissues. The expression profiles showed significant changes in DNA damage related genes in 2 Gy proton exposed mouse brain tissues as compared to control brain tissues. Furthermore, we also show that significantly increased levels of apoptotic related genes, caspase-3 and 8 activities in these cells, suggesting that in addition to differential expression of DNA damage genes, the alteration of apoptosis related genes may also contribute to the radiation induced DNA damage followed by programmed cell death. In summary, our findings suggest that proton exposed cells undergo severe DNA damage which in turn destabilize the chromatin stability. 相似文献
63.
Emission analysis of Tb3+‐and Sm3+‐ion‐doped (Li2O/Na2O/K2O) and (Li2O + Na2O/Li2O + K2O/K2O + Na2O)‐modified borosilicate glasses 下载免费PDF全文
B. Naveen Kumar Reddy S. Sailaja K. Thyagarajan Young Dahl Jho B. Sudhakar Reddy 《Luminescence》2018,33(3):486-494
Four series of borosilicate glasses modified by alkali oxides and doped with Tb3+ and Sm3+ ions were prepared using the conventional melt quenching technique, with the chemical composition 74.5B2O3 + 10SiO2 + 5MgO + R + 0.5(Tb2O3/Sm2O3) [where R = 10(Li2O /Na2O/K2O) for series A and C, and R = 5(Li2O + Na2O/Li2O + K2O/K2O + Na2O) for series B and D]. The X‐ray diffraction (XRD) patterns of all the prepared glasses indicate their amorphous nature. The spectroscopic properties of the prepared glasses were studied by optical absorption analysis, photoluminescence excitation (PLE) and photoluminescence (PL) analysis. A green emission corresponding to the 5D4 → 7F5 (543 nm) transition of the Tb3+ ions was registered under excitation at 379 nm for series A and B glasses. The emission spectra of the Sm3+ ions with the series C and D glasses showed strong reddish‐orange emission at 600 nm (4G5/2 →6H7/2) with an excitation wavelength λexci = 404 nm (6H5/2→4F7/2). Furthermore, the change in the luminescence intensity with the addition of an alkali oxide and combinations of these alkali oxides to borosilicate glasses doped with Tb3+ and Sm3+ ions was studied to optimize the potential alkali‐oxide‐modified borosilicate glass. 相似文献
64.
65.
Sanjay Kumar Singh Nitin Nage Hitesh Jagani Mukul Maiti Ranjit Sudhakar Ranbhor 《Reproductive biology》2018,18(4):380-384
In humans, regulation of reproductive functions are carried out mainly by glycoprotein hormones namely follicle stimulating hormone (FSH), thyroid stimulating hormone (TSH), luteinizing hormone (LH) and chorionic gonadotropin (CG). Since glycans play an important role in binding of gonadotropins with their respective receptors, it is important to identify associated glycans and their pharmacological properties not only for the disease manipulation but also for making more efficacious and safer recombinant versions. With the advancement of mass spectrometry, it is possible to identify minute quantity of associated glycans. Here, we studied the N-glycans of the FSH based on mass spectrometry and report one more complex glycan species in addition to twenty four previously reported glycans. The new glycan was a tetra antennary species that may have important role in binding of FSH with receptor with higher biological activity as well as lower clearance rate and higher half-life. 相似文献
66.
67.
P. Sudhakar Babu A. N. Vaidya A. S. Bal Rajesh Kapur Asha Juwarkar P. Khanna 《Biotechnology letters》1996,18(3):263-268
Summary Batch kinetic studies were carried out on rhamnolipid biosurfactant production from synthetic medium, industrial wastes viz. distillery and whey waste as substrates. The results indicated that the specific growth rates ( max) and specific product formation rates (V max) from both the wastes are comparatively better than the synthetic medium, revealing that both the industrial wastes (distillery and whey) can be successfully utilized as substrates for biosurfactant production. 相似文献
68.
T. Sudhakar Johnson G. A. Ravishankar L. V. Venkataraman 《Plant Cell, Tissue and Organ Culture》1996,46(2):117-121
Plant tissue culture medium which contained FeEDTA as sole iron source was incubated aseptically in light (16-h photoperiod, 100 mol m-2 s-1 PAR) at 20°C without plant tissue. Soluble iron dropped from an initial concentration of 4 mg 1-1 to less than 0.1 mg 1-1 in 4 weeks. This occurred in both glass and plastic culture vessels. No loss occurred when medium was incubated at 20°C in darkness. A further experiment showed that soluble iron concentration fell to <0.2 mg 1-1 in only 4 days but the loss was slower at lower irradiances.Effects of the loss of soluble iron on plantlet growth were assessed by culturing single node stem segments of in vitro potato (Solanum tuberosum L. cv. Arran Banner) plantlets on medium previously exposed to light. Pre-exposure sufficient to reduce soluble iron concentration to <0.1 mg 1-1 had no inhibitory effect on plantlet development in solidified medium or in liquid medium, except when the liquid medium had been centrifuged before inoculation to remove iron precipitated during pre-exposure to light. The plantlets then became chlorotic. 相似文献
69.
S Prasad A Mathur M Jaggi R Sharma N Gupta V R Reddy G Sudhakar S U Kumar S K Kumar A C Kunwar T K Chakraborty 《The journal of peptide research》2005,66(2):75-84
In this study we describe the development of peptidomimetic analogs of the potent vasoactive intestinal peptide receptor binding inhibitor, Leu(1) -Met(2) -Tyr(3) -Pro(4) -Thr(5) -Tyr(6) -Leu(7) -Lys(8) -OH 1, by incorporating furanoid sugar amino acids (SAAs) 2-4 into the molecule. The furanoid SAAs 2-4 were used as dipeptide isosteres to replace Tyr(3) -Pro(4) or Pro(4) -Thr(5) in sequence 1. The resulting analogs 5-9 were tested for their anti-cancer activities in vitro, following the standard MTT assay on a panel of human cancer cell lines. One of the potent analogs, 6a was tested in vivo for tumor regression on primary colon tumor xenografted nude mice. Our experimental results suggest that many of these analogs show either retention or enhancement of biological activity. 相似文献
70.
A promising RVO4:Eu3+,Li+@SiO2 (R = Gd,Y and Gd/Y) red‐emitting phosphor with improved luminescence (cd/m2) and colour purity for optical display applications 下载免费PDF全文
Urlagaddala Rambabu Nagegownivari Ramachandra Munirathnam Busireddy Sudhakar Reddy Sandip Chatterjee 《Luminescence》2016,31(1):141-151
Red emission intensity was optimized in three stages, by investigating the effects of: (i) host composition (Gd, Y and Gd/Y), (ii) codoping Li+ as a sensitizer and, finally, (iii) with a SiO2 shell coating as a protecting layer. Lanthanide vanadate powder phosphors were synthesized using a modified colloidal precipitation technique. The effects of SiO2 coating on phosphor particles were characterized using scanning electron microscopy (SEM)‐EDAX, transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and photoluminescence (PL) measurements. An improvement in the PL intensity on Li codoping was due to improved crystallinity, which led to higher oscillating strengths for the optical transitions, and also a lowering of the inversion symmetry of Eu3+ ions. Red emission intensity due to 5D0 → 5D2 transition of the phosphor Y0.94VO4:Eu3+0.05,Li+0.01 was enhanced by 22.28% compared with Y0.95VO4:Eu3+0.05, and was further improved by 58.73% with SiO2 coating. The luminescence intensity (I) and colour coordinates (x, y) of the optimized phosphor Y0.94VO4:Eu3+0.05,Li+0.01@SiO2, where I = 13.07 cd/m2 and (x = 0.6721, y = 0.3240), were compared with values for a commercial red phosphor (Y2O2S:Eu3+), where I = 27 cd/m2 and (x = 0.6522, y = 0.3437). The measured colour coordinates are superior to those of the commercial red phosphor, and moreover, match well with standard NTSC values (x = 0.67, y = 0.33). Copyright © 2015 John Wiley & Sons, Ltd. 相似文献