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401.
402.
Amey J. Bhide Sonal M. Channale Yashpal Yadav Kabita Bhattacharjee Pankaj K. Pawar V. L. Maheshwari Vidya S. Gupta Sureshkumar Ramasamy Ashok P. Giri 《Plant molecular biology》2017,94(3):319-332
The smallest 32 amino acid α-amylase inhibitor from Amaranthus hypochondriacus (AAI) is reported. The complete gene of pre-protein (AhAI) encoding a 26 amino acid (aa) signal peptide followed by the 43 aa region and the previously identified 32 aa peptide was cloned successfully. Three cysteine residues and one disulfide bond conserved within known α-amylase inhibitors were present in AhAI. Identical genomic and open reading frame was found to be present in close relatives of A. hypochondriacus namely Amaranthus paniculatus, Achyranthes aspera and Celosia argentea. Interestingly, the 3′UTR of AhAI varied in these species. The highest expression of AhAI was observed in A. hypochondriacus inflorescence; however, it was not detected in the seed. We hypothesized that the inhibitor expressed in leaves and inflorescence might be transported to the seeds. Sub-cellular localization studies clearly indicated the involvement of AhAI signal peptide in extracellular secretion. Full length rAhAI showed differential inhibition against α-amylases from human, insects, fungi and bacteria. Particularly, α-amylases from Helicoverpa armigera (Lepidoptera) were not inhibited by AhAI while Tribolium castaneum and Callosobruchus chinensis (Coleoptera) α-amylases were completely inhibited. Molecular docking of AhAI revealed tighter interactions with active site residues of T. castaneum α-amylase compared to C. chinensis α-amylase, which could be the rationale behind the disparity in their IC50. Normal growth, development and adult emergence of C. chinensis were hampered after feeding on rAhAI. Altogether, the ability of AhAI to affect the growth of C. chinensis demonstrated its potential as an efficient bio-control agent, especially against stored grain pests. 相似文献
403.
Extraction of Y2O3:Cr3+ nanophosphor by eco‐friendly approach and its suitability for white light‐emitting diode applications
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J. B. Prasanna Kumar G. Ramgopal D. V. Sunitha B. Daruka Prasad H. Nagabhushana Y. S. Vidya K. S. Anantharaju S. C. Prashantha S. C. Sharma K. R. Prabhakara 《Luminescence》2017,32(3):414-424
Cr3+‐doped Y2O3 (0.5–9 mol%) was synthesized by a simple solution combustion method using Aloe vera gel as a fuel/surfactant. The final obtained product was calcined at 750°C for 3 h, which is the lowest temperature reported so far for the synthesis of this compound. The calcined product was confirmed for its crystallinity and purity by powder X‐ray diffraction (PXRD) studies which showed a single‐phase nano cubic phosphor. The particles size estimated by Scherrer formula was in the range of 6–19 nm. The UV–vis spectra showed absorption bands at 198, 272 and 372 nm having band gap energy in the range 4.00–4.26 eV. In order to investigate the possibility of its use in white light emitting display applications, the photoluminescence properties of Cr3+‐doped Y2O3 nanophosphors were studied at an excitation wavelength in the near ultraviolet (UV) light region (361 nm). The emission spectra consisted of emission peaks in the blue (4F9/2 → 6H15/2), orange (4F9/2 → 6H13/2) and red (4F9/2 → 6H11/2) regions. The CIE coordinates (0.33, 0.33) lie in the white light region. Hence Y2O3:Cr3+ can be used for white light‐emitting diode (LED) applications. 相似文献
404.
Vav activation and function as a rac guanine nucleotide exchange factor in macrophage colony-stimulating factor-induced macrophage chemotaxis
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Signal transduction mediated by phosphatidylinositol 3-kinase (PI 3-kinase) is regulated by hydrolysis of its products, a function performed by the 145-kDa SH2 domain-containing inositol phosphatase (SHIP). Here, we show that bone marrow macrophages of SHIP(-/-) animals have elevated levels of phosphatidylinositol 3,4,5-trisphosphate [PI (3,4,5)P(3)] and displayed higher and more prolonged chemotactic responses to macrophage colony-stimulating factor (M-CSF) and elevated levels of F-actin relative to wild-type macrophages. We also found that the small GTPase Rac was constitutively active and its upstream activator Vav was constitutively phosphorylated in SHIP(-/-) macrophages. Furthermore, we show that Vav in wild-type macrophages is recruited to the membrane in a PI 3-kinase-dependent manner through the Vav pleckstrin homology domain upon M-CSF stimulation. Dominant inhibitory mutants of both Rac and Vav blocked chemotaxis. We conclude that Vav acts as a PI 3-kinase-dependent activator for Rac activation in macrophages stimulated with M-CSF and that SHIP regulates macrophage M-CSF-triggered chemotaxis by hydrolysis of PI (3,4,5)P(3). 相似文献
405.
406.
Reliable noninvasive genotyping: fantasy or reality? 总被引:9,自引:0,他引:9
Noninvasive genotyping has not gained wide application, due to the notion that it is unreliable, and also because remedial measures are time consuming and expensive. Of the wide variety of noninvasive DNA sources, dung is the most universal and most widely used in studies. We have developed collection, extraction, and amplification protocols that are inexpensive and provide a high level of success in amplifying both mitochondrial and nuclear DNA from dung. Here we demonstrate the reliability of genotyping from elephant dung using these protocols by comparing results from dung-extracted DNA to results from blood-extracted DNA. The level of error from dung extractions was only slightly higher than from blood extractions, and conducting two extractions from each sample and a single amplification from each extraction was sufficient to eliminate error. Di-, tri-, and tetranucleotide loci were equally reliable, and low DNA quantity and quality and PCR inhibitors were not a major problem in genotyping from dung. We discuss the possible causes of error in genotyping with particular reference to noninvasive samples and suggest methods of reducing such error. 相似文献
407.
Structure-function relationships of human C5a and C5aR 总被引:2,自引:0,他引:2
Huber-Lang MS Sarma JV McGuire SR Lu KT Padgaonkar VA Younkin EM Guo RF Weber CH Zuiderweg ER Zetoune FS Ward PA 《Journal of immunology (Baltimore, Md. : 1950)》2003,170(12):6115-6124
Using peptides that represent linear regions of the powerful complement activation product, C5a, or loops that connect the four alpha helices of C5a, we have defined the ability of these peptides to reduce binding of (125)I-C5a to human neutrophils, inhibit chemotactic responses of neutrophils to C5a, and reduce H(2)O(2) production in neutrophils stimulated with PMA. The data have defined likely sites of interaction of C5a with C5aR. The peptides had no functional activity per se on neutrophils and did not interfere with neutrophil responses to the unrelated chemotactic peptide, N-formyl-Met-Leu-Phe. Although previous data have suggested that there are two separate sites on C5a reactive with C5aR, the current data suggest that C5a interacts with C5aR in a manner that engages three discontinuous regions of C5a. 相似文献
408.
Kunjathoor VV Febbraio M Podrez EA Moore KJ Andersson L Koehn S Rhee JS Silverstein R Hoff HF Freeman MW 《The Journal of biological chemistry》2002,277(51):49982-49988
Modification of low density lipoprotein (LDL) can result in the avid uptake of these lipoproteins via a family of macrophage transmembrane proteins referred to as scavenger receptors (SRs). The genetic inactivation of either of two SR family members, SR-A or CD36, has been shown previously to reduce oxidized LDL uptake in vitro and atherosclerotic lesions in mice. Several other SRs are reported to bind modified LDL, but their contribution to macrophage lipid accumulation is uncertain. We generated mice lacking both SR-A and CD36 to determine their combined impact on macrophage lipid uptake and to assess the contribution of other SRs to this process. We show that SR-A and CD36 account for 75-90% of degradation of LDL modified by acetylation or oxidation. Cholesteryl ester derived from modified lipoproteins fails to accumulate in macrophages taken from the double null mice, as assessed by histochemistry and gas chromatography-mass spectrometry. These results demonstrate that SR-A and CD36 are responsible for the preponderance of modified LDL uptake in macrophages and that other scavenger receptors do not compensate for their absence. 相似文献
409.
Prabhu VP Simons AM Iwasaki H Gai D Simmons DT Chen J 《Journal of molecular biology》2002,316(5):1023-1032
The Holliday junction is the central intermediate in homologous recombination. Branch migration of this four-stranded DNA structure is a key step in genetic recombination that affects the extent of genetic information exchanged between two parental DNA molecules. Here, we have constructed synthetic Holliday junctions to test the effects of p53 on both spontaneous and RuvAB promoted branch migration as well as the effect on resolution of the junction by RuvC. We demonstrate that p53 blocks branch migration, and that cleavage of the Holliday junction by RuvC is modulated by p53. These findings suggest that p53 can block branch migration promoted by proteins such as RuvAB and modulate the cleavage by Holliday junction resolution proteins such as RuvC. These results suggest that p53 could have similar effects on eukaryotic homologues of RuvABC and thus have a direct role in recombinational DNA repair. 相似文献
410.
Amelioration of osmotic stress by brassinosteroids on seed germination and seedling growth of three varieties of sorghum 总被引:4,自引:0,他引:4
The effect of 28-homobrassinolide and 24-epibrassinolide on the germination and seedling growth of three varieties of sorghum, viz. CSH-14 and ICSV-745 (susceptible to water stress) and M-35-1 (resistant to water stress), under osmotic stress conditions was studied. Both the brassinosteroids were very effective in increasing the percentage of germination and seedling growth of all the three varieties of sorghum under osmotic stress, the growth promotion being associated with enhanced levels of soluble proteins and free proline. Brassinosteroid treatment enhanced the activity of catalase and reduced the activities of peroxidase and ascorbic acid oxidase. 相似文献