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排序方式: 共有143条查询结果,搜索用时 15 毫秒
31.
Riyaj S. Tamboli Rajani Giridhar Hardik P. Gandhi Ashish M. Kanhed Hemant M. Mande 《Journal of enzyme inhibition and medicinal chemistry》2016,31(5):704-713
The aim of this research work was to investigate a series of novel 5,6-diaryl-1,2,4-triazines (3a–3q) containing 3-morpholinoethylamine side chain, and to address their antiplatelet activity by in vitro, ex vivo and in vivo methods. All compounds were synthesized by environment benign route and their structures were unambiguously confirmed by spectral data. Compounds (3l) and (3m) were confirmed by their single crystal X-ray structures. Out of all the synthesized compounds, 10 were found to be more potent in vitro than aspirin; six of them were found to be prominent in ex vivo assays and one compound (3d) was found to have the most promising antithrombotic profile in vivo. Moreover, compound (3d) demonstrated less ulcerogenicity in rats as compared to aspirin. The selectivity of the most promising compound (3d) for COX-1 and COX-2 enzymes was determined with the help of molecular docking studies and the results were correlated with the biological activity. 相似文献
32.
We have isolated the delta-globin gene of the New-World spider monkey,
Ateles geoffroyi, and compared its nucleotide sequence with those of other
primate delta- and beta-globin genes. Among primate delta-globin genes, the
rate of nonsynonymous substitutions is much less than the rate of
synonymous substitutions. This suggests that primate delta- globin genes
may remain under evolutionary conservation, perhaps because hemoglobin A2
has an as yet unknown physiological importance.
相似文献
33.
J. E. Friedman P. I. Lelkes E. Lavie K. Rosenheek F. Schneeweiss RA. S. Schneider† 《Journal of neurochemistry》1985,44(5):1391-1402
Changes in plasma membrane potential of isolated bovine adrenal chromaffin cells were measured independently by two chemical probe methods and related to corresponding effects on catecholamine secretion. The lipophilic cation tetraphenylphosphonium (TPP+) and the carbocyanine dye 3,3'-dipropylthiadicarbocyanine [DiS-C3-(5)] were used. The necessity of evaluating the subcellular distribution of TPP+ among cytoplasmic, mitochondrial, secretory granule, and bound compartments was demonstrated and the resting plasma membrane potential determined to be -55 mV. The relationship between membrane potential and catecholamine secretion was determined in response to variations in extracellular K+ and to the presence of several secretagogues including cholinergic receptor ligands, veratridine, and ionophores for Na+ and K+. The dependence of potential on K+ concentration fit the Goldman constant field equation with a Na/K permeability ratio of 0.1. The dependence of both K+- and veratridine-evoked catecholamine secretion on membrane potential exhibited a potential threshold of about -40 mV before a significant rise in secretion occurred. This is likely related to the threshold for opening of voltage-sensitive Ca2+ channels. Acetylcholine and nicotine evoked a large secretory response without a sufficiently sustained depolarization to be detectable by the relatively slow potential sensitive chemical probes. Decamethonium induced a detectable depolarization of the chromaffin cells. Veratridine and gramicidin evoked both membrane depolarization and catecholamine release. By contrast the K ionophore valinomycin evoked significant levels of secretion without any depolarization. This is consistent with its utilization of an intracellular source of Ca2+ and the independence of its measured secretory response on extracellular Ca2+. 相似文献
34.
Asif?S.?Tamboli Pradnya?B.?Yadav Aatiya?A.?Gothe Shrirang?R.?Yadav Sanjay?P.?GovindwarEmail author 《Plant Systematics and Evolution》2018,304(2):205-217
Capparis (Capparaceae) has been used as a medicinal plant since ancient time. Capparis species were divided into Old World and New World taxa as described by the sectional division of Capparis. However, plastid DNA sequence data of Indian Capparis species were not analyzed in previous phylogenetic studies. Here, we have added Indian Capparis data in previous phylogeny and analyzed the relationship of Indian Capparis with Old World and New World taxa. The plastid phylogeny presented here includes Capparis taxa from its major distribution areas, New World and African capparoids. The presented phylogeny is used for the determination of biogeographic history of Capparis and recently segregated genera. Phylogenetic analyses of the combined plastid data revealed that the Indian Capparis are more closely related to Old World taxa and have connections with African, Australian and Eastern Asian species. Sectional classification of Old World and Indian Capparis considered in this study is reflected from the presented plastid phylogeny. The ancestral area reconstruction using Bayesian Binary Markov Chain Monte Carlo method strongly supports for the Africa as the ancestral region for both Old World and New World Capparis. Molecular marker-based genetic diversity studies on Indian Capparis are scarce. This work also includes the genetic diversity study of Indian Capparis species. Utility and efficacy of ISSR markers to study inter- and intraspecies variation in Capparis is evident from the AMOVA results. 相似文献
35.
There are gaps in existing understanding of fungal pellet growth dynamics. We used scanning electron microscopy (SEM) for morphological characterization of the biomass organization of Termitomyces pellets for seven species: T. microcarpus (TMI1), T. albuminosus (TAL1, TAL2), T. striatus (TSTR), T. aurantiacus (TAUR), T. heimii (THE1, THE2), T. globulus (TGLO) and T. clypeatus (TCL1, TCL2, TCL3, TCL4, TCL5). We assessed the utility of SEM for morphological and structural characterization of Termitomyces spp. in three dimensional (3D) pellet form to identify ideal pellet morphology for industrial use. Typological classification of Termitomyces species was based on furrows, isotropy, total motifs and fractal dimensions. The pellets formed were entangled and exhibited highly compacted mycelial mass with microheterogeneity and microporosity. The mean density of furrows of Termitomyces species was between 10,000 and 11,300 cm/cm2, percentage isotropy was 30?80 and total motifs varied from 300 to 2500. TGLO exhibited the highest furrow mean density, 11243 cm/cm2, which indicated a compact, cerebroid structure with complex ridges and furrows, whereas TAL2 exhibited the lowest furrow density. TMI1a exhibited a high percentage isotropic value, 74.6, TSTR exhibited the lowest, 30.9. Total motif number also was used as a typological classification parameter. Fractal values were 2.64?2.78 for various submerged conditions of Termitomyces species. TAL1 exhibited the highest fractal dimension and TAL2 the lowest, which indicates the complexity of branching patterns. Three-dimensional SEM image analysis can provide insight into pellet micromorphology and is a powerful tool for exploring topographical details of pellets. 相似文献
36.
Sea urchin Hox genes: insights into the ancestral Hox cluster 总被引:3,自引:0,他引:3
We describe the Hox cluster in the radially symmetric sea urchin and
compare our findings to what is known from clusters in bilaterally
symmetric animals. Several Hox genes from the direct-developing sea urchin
Heliocidaris erythrogramma are described. CHEF gel analysis shows that the
Hox genes are clustered on a < or = 300 kilobase (kb) fragment of DNA,
and only a single cluster is present, as in lower chordates and other
nonvertebrate metazoans. Phylogenetic analyses of sea urchin, amphioxus,
Drosophila, and selected vertebrate Hox genes confirm that the H.
erythrogramma genes, and others previously cloned from other sea urchins,
belong to anterior, central, and posterior groups. Despite their radial
body plan and lack of cephalization, echinoderms retain at least one of the
anterior group Hox genes, an orthologue of Hox3. The structure of the
echinoderm Hox cluster suggests that the ancestral deuterostome had a Hox
cluster more similar to the current chordate cluster than was expected Sea
urchins have at least three Abd-B type genes, suggesting that Abd-B
expansion began before the radiation of deuterostomes.
相似文献
37.
Photoluminescence and electron paramagnetic resonance properties of a potential phototherapic agent: MMgF4:Gd3+ (M = Ba,Sr) sub‐microphosphors
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Novel narrow band UVB‐emitting phosphors, BaMgF4:Gd3+ and SrMgF4:Gd3+ phosphors, were synthesized using a co‐precipitation synthesis method. X‐Ray diffraction analysis was carried out to confirm compound formation, phase purity and crystallinity of the phosphor. At 274 nm excitation, phosphors show a sharp narrow band emission at 313 nm that can be assigned to 6P7/2 → 8S7/2 transition of the Gd3+ ion. With increasing dopant concentration, intensity enhances and then decreases after a certain concentration, which is an indication of concentration quenching taking place in the phosphor. Scanning electron microscopy images of the phosphor show agglomerated particles in the sub‐micron range. Particles range in size from 600 to 800 nm. Electron paramagnetic resonance studies of the phosphors were carried out to detect radicals present in the prepared phosphor. With narrow band UVB emission, phosphor seems to be a good candidate for UV phototherapy application. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
38.
Incorporating the Gd3+ rare earth ion in the LiCaBO3 host lattice resulted in narrow‐band UV‐B emission peaking at 315 nm, with excitation at 274 nm. The LiCaBO3:Gd3+ phosphor was synthesized via the solid‐state diffusion method. The structural, morphological and luminescence properties of this phosphor were characterized by X‐ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and photoluminescence (PL) spectroscopy. Electron paramagnetic resonance (EPR) characterization of the as‐prepared phosphors is also reported here. XRD studies confirmed the crystal formation and phase purity of the prepared phosphors. A series of different dopant concentrations was synthesized and the concentration‐quenching effect was studied. Critical energy transfer distance between activator ions was determined and the mechanism governing the concentration quenching is also reported in this paper. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
39.
40.
Tamboli Y Lazzarato L Marini E Guglielmo S Novelli M Beffy P Masiello P Fruttero R Gasco A 《Bioorganic & medicinal chemistry letters》2012,22(11):3810-3815
We describe a new class of NO-donor hypoglycemic products obtained by joining tolbutamide, a typical hypoglycemic sulfonylurea, with a NO-donor moiety through a hard link. As NO-donors we chose either furoxan (1,2,5-oxadiazole 2-oxide) derivatives or the classical nitrooxy function. A preliminary biological characterization of these compounds, including stimulation of insulin release from cultured rat pancreatic β-cells and in vitro vasodilator and anti-aggregatory activities, is reported. 相似文献