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41.
Shu-Biao Wu Iraj Tavassolian Gholamreza Rabiei Peter Hunt Michelle Wirthensohn John P. Gibson Christopher M. Ford Margaret Sedgley 《Molecular genetics and genomics : MGG》2009,282(3):273-281
Peach and almond have been considered as model species for the family Rosaceae and other woody plants. Consequently, mapping
and characterisation of genes in these species has important implications. High-resolution melting (HRM) analysis is a recent
development in the detection of SNPs and other markers, and proved to be an efficient and cost-effective approach. In this
study, we aimed to map genes corresponding to known proteins in other species using the HRM approach. Prunus unigenes were searched and compared with known proteins in the public databases. We developed single-nucleotide polymorphism
(SNP) markers, polymorphic in a mapping population produced from a cross between the cloned cultivars Nonpareil and Lauranne.
A total of 12 SNP-anchored putative genes were genotyped in the population using HRM, and mapped to an existing linkage map.
These genes were mapped on six linkage groups, and the predicted proteins were compared to putative orthologs in other species.
Amongst those genes, four were abiotic stress-responsive genes, which can provide a starting point for construction of an
abiotic resistance map. Two allergy and detoxification related genes, respectively, were also mapped and analysed. Most of
the investigated genes had high similarities to sequences from closely related species such as apricot, apple and other eudicots,
and these are putatively orthologous. In addition, it was shown that HRM can be an effective means of genotyping populations
for the purpose of constructing a linkage map. Our work provides basic genomic information for the 12 genes, which can be
used for further genetic and functional studies. 相似文献
42.
Shadab Gharaati Shahram Tangestaninejad Valiollah Mirkhani Iraj Mohammadpoor-Baltork Farshid Kosari 《Inorganica chimica acta》2010,363(9):1995-646
An efficient and selective method for methoxymethylation of alcohols and phenols with formaldehyde dimethyl acetal (FDMA) catalyzed by electron deficient tin(IV)tetraphenylporphyrinato trifluoromethanesulfonate, [SnIV(TPP)(OTf)2], is reported. A variety of primary, secondary and tertiary alcohols as well as phenols were converted to their corresponding methoxymethyl ethers with FDMA in the presence of a high-valent tin(IV) porphyrin. This catalyst can be used for selective methoxymethylation of primary, secondary and tertiary alcohols in the presence of phenols or tertiary alcohols. The present method offers several advantages such as short reaction times, high yields, simple procedure, selectivity and applicability for both alcohols and phenols. 相似文献
43.
44.
Effector binding to liganded hemoglobin (Hb) provides a new understanding of structural determinants of Hb function. L35, a bezafibrate-related compound, is one of the more potent synthetic regulators of Hb oxygen (O(2)) affinity. In the presence of inositol hexaphosphate and bezafibrate (or derivatives), liganded Hb at low pH (pH approximately 6.5) exhibits extremely low O(2) affinity and very low cooperativity. In this study, the nature of L35 binding to COHbA at pH 6.35, an altered R-state, is presented. Solution-active site-specific spectroscopic probings by front-face fluorescence and circular dichroism reveal that L35 induces a global heterogeneous conformation in COHbA at pH 6.35 that includes: a T-like structural feature at the alpha1beta2 interface; an R-like structural feature within the heme environment; and an intermediate-like state at the central cavity. These long-range structural perturbations appear to stem from L35 binding to two classes of binding sites: the central cavity (primarily at the alphaalpha cleft) and the surface. These results indicate that L35 induces an allosteric transition species, characterized by domain-specific tertiary and quaternary-like conformation within a global R-quaternary structure. 相似文献
45.
EPIYA motif is a membrane-targeting signal of Helicobacter pylori virulence factor CagA in mammalian cells 总被引:11,自引:0,他引:11
Higashi H Yokoyama K Fujii Y Ren S Yuasa H Saadat I Murata-Kamiya N Azuma T Hatakeyama M 《The Journal of biological chemistry》2005,280(24):23130-23137
Helicobacter pylori contributes to the development of peptic ulcers and atrophic gastritis. Furthermore, H. pylori strains carrying the cagA gene are more virulent than cagA-negative strains and are associated with the development of gastric adenocarcinoma. The cagA gene product, CagA, is translocated into gastric epithelial cells and localizes to the inner surface of the plasma membrane, in which it undergoes tyrosine phosphorylation at the Glu-Pro-Ile-Tyr-Ala (EPIYA) motif. Tyrosine-phosphorylated CagA specifically binds to and activates Src homology 2-containing protein-tyrosine phosphatase-2 (SHP-2) at the membrane, thereby inducing an elongated cell shape termed the hummingbird phenotype. Accordingly, membrane tethering of CagA is an essential prerequisite for the pathogenic activity of CagA. We show here that membrane association of CagA requires the EPIYA-containing region but is independent of EPIYA tyrosine phosphorylation. We further show that specific deletion of the EPIYA motif abolishes the ability of CagA to associate with the membrane. Conversely, reintroduction of an EPIYA sequence into a CagA mutant that lacks the EPIYA-containing region restores membrane association of CagA. Thus, the presence of a single EPIYA motif is necessary for the membrane localization of CagA. Our results indicate that the EPIYA motif has a dual function in membrane association and tyrosine phosphorylation, both of which are critically involved in the activity of CagA to deregulate intracellular signaling, and suggest that the EPIYA motif is a crucial therapeutic target of cagA-positive H. pylori infection. 相似文献
46.
The essential oils from Thymus eriocalyx and Thymus X-porlock obtained by hydrodistillation were analyzed by GC/MS. The major components of T. eriocalyx and T. X-porlock oils were thymol (63.8, 31.7%), beta-phellandrene (13.30, 38.7%), cis-sabinene hydroxide (8.1, 9.6%), 1,8-cineole (2, 1.7%), and beta-pinene (1.31, 2%), respectively. Antifungal activities of the oils were studied with special reference to the inhibition of Aspergillus parasiticus growth and aflatoxin production. Minimal inhibitory (MIC) and minimal fungicidal (MFC) concentrations of the oils were determined. Static effects of the above oils against A. parasiticus were at 250 ppm and lethal effects of T. eriocalyx and T. X-porlock were 500 and 1000 ppm of the oils, respectively. Aflatoxin production was inhibited at 250 ppm of both oils with that of T. eriocalyx being stronger inhibitor. Transmission electron microscopy (TEM) of A. parasiticus exposed to MIC level (250 ppm) of the oils showed irreversible damage to cell wall, cell membrane, and cellular organelles. It is concluded that the essential oils could be safely used as preservative materials on some kinds of foods at low concentrations to protect them from fungal infections. 相似文献
47.
48.
Simple chemiluminescence determination of ketotifen using tris(1,10 phenanthroline)ruthenium(II)‐ Ce(IV) system
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Ali Mokhtari Mehrgan Ghazaeian Mahdieh Maghsoudi Mohsen Keyvanfard Iraj Emami 《Luminescence》2015,30(7):1094-1100
A new method using chemiluminescence (CL) detection has been developed for the simple determination of ketotifen fumarate (KF). The method is based on the catalytic effect of KF in the CL reaction of tris(1,10 phenanthroline)ruthenium(II), Ru(phen)32+, with Ce(IV) in sulfuric acid medium. The CL response was detected using a lab‐made chemiluminometer. Effects of chemical variables were investigated and under optimum conditions, the CL intensity was proportional to the concentration of the drug over the range 0.34‐34.00 µg mL?1 KF. The limit of detection (S/N=3) was 0.09 µg mL?1. Effects of common ingredients were investigated and the method was applied successfully for determining KF in pharmaceutical formulations and human plasma. The percent of relative standard deviation (n=11) at level of 3.4 µg mL?1 of KF was 4.6% and the minimum sampling rate was 70 samples per hour. The possible CL mechanism is proposed based on the kinetic characteristic of the CL reaction, CL spectrum, UV‐Vis and phosphorescence spectra. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
49.
Ghazaleh Jahanshah Iraj Nahvi Sayyed Hamid Zarkesh-Esfahani Hossein Ghanavati Hanif Khodaverdi Morteza Barani 《Annals of microbiology》2013,63(1):91-100
Wild screening of bacterial strains from compost materials was performed. Several biosurfactant-producer strains were isolated and then cultured in whey as a low-cost medium for biosurfactant production. Two strains, identified as Bacillus sp. and Streptomyces sp., were the best biosurfactant producers and were selected for determination of compost quality enhancing. The effect of cell biomass, cell-free supernatant, and a consortium of these two strains on compost quality were determined and specific parameters of compost were analyzed. The results showed that using these bacteria (or supernatants) in compost processing have slight stimulatory effect on bacterial population (8.08 log10 CFU/g), surface tension reduction (to 42.6 mN/m at 24 h), and heavy metal bioremediation (>50 % in most treatments), speeding up the decomposition rate of organic matter (42.3 % OM at the end of experiment), accelerating the stabilization process by reduction of NH 4 + to NO 3 ? ratio (reduced from 0.2 to 0.026), decreasing the biotoxicity (tested by seed germination and root length of germinated seed), and also reduction of pathogens (reduced from 2100 to 120 MPN/g in fecal coliform). 相似文献