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91.
AE Clarke S Bernatsky KH Costenbader MB Urowitz DD Gladman PR Fortin M Petri S Manzi DA Isenberg A Rahman D Wallace C Gordon C Peschken MA Dooley EM Ginzler C Aranow SM Edworthy O Nived S Jacobsen G Ruiz-Irastorza E Yelin SG Barr L Criswell G Sturfelt L Dreyer I Blanco L Gottesman CH Feldman R Ramsey-Goldman 《Arthritis research & therapy》2012,14(Z3):A16
92.
Phylogeny of Psephenidae (Coleoptera: Byrrhoidea) based on larval, pupal and adult characters 总被引:1,自引:0,他引:1
CHI-FENG LEE MASATAKA SATÔ WILLIAM D. SHEPARD MANFRED A. JÄCH 《Systematic Entomology》2007,32(3):502-538
Abstract. We conducted the first comprehensive phylogenetic analysis of Psephenidae, based on 143 morphological characters of adults, larvae and pupae and coded for 34 taxa, representing three outgroups and 31 psephenid genera, including four undescribed ones. A strict consensus tree calculated (439 steps, consistency index = 0.45, retention index = 0.75) from the two most-parsimonious cladograms indicated that the monophyly of the family and subfamilies is supported, with the exception of Eubriinae, which is paraphyletic when including Afroeubria . Here a new subfamily, Afroeubriinae ( subfam.n. ), is formally established for Afroeubria . The analysis also indicated that the 'streamlined' larva is a derived adaptive radiation. Here, suprageneric taxonomy and the evolution of some significant characters are discussed. Keys are provided to the subfamilies and genera of Psephenidae considering larvae, adults and pupae. 相似文献
93.
Konidala Sathish Kumar Vijay Kotra CH.B. Praveena Devi Nutakki Anusha Bollikolla Hari Babu Syed Farooq Adil Mohammed Rafi Shaik Mujeeb Khan Abdulrahman Al-Warthan Osamah Alduhaish M. Mujahid Alam 《Saudi Journal of Biological Sciences》2021,28(1):386-394
A new series of coumarin-yl-chalcone derivatives (3a-m) had been designed and synthesized through different reactions such as aromatic addition, cyclization and Claisen-Schmidt reactions in good yields (54–78%). 5-acetyl-4-(2-hydroxyphenyl) -6-methyl-3, 4-dihydropyrimidin-2(1H) -one (1) has been synthesized by multi-component one pot reaction of salicylaldehyde, methyl acetoacetate and urea, which was further reacted with malonic acid employing ZnCl2 catalyst to yield 5-acetyl-4-(4-hydroxy-2-oxo-2H-chromen-8-yl) -6-methyl-3, 4-dihydropyrimidin-2(1H) -one (2). The title compounds (3a-m) were synthesised by reacting 5-acetyl-4-(4-hydroxy-2-oxo-2H-chromen-8-yl) -6-methyl-3, 4-dihydropyrimidin-2(1H)-one (2) with different aromatic aldehydes in the presence of potassium hydroxide. In silico studies, a preliminary screening method for predicting the anti-cancer activity was performed for the synthesized compounds (3a-m) against Src, Alb tyrosine kinase and homology model protein (PDB ID: 4csv). The derivatives 3h and 3m showed moderate binding energies. The in vitro cytotoxic activity was evaluated for the compounds 3h and 3m by using human cancer cell-line morphology and MTT assay against three human cell-lines A549 (Lung), Jurkat (Leukemia) and MCF-7 (Breast). The results indicate that the derivatives 3h and 3m display significant anti-cancer activity, however it was found to be less cytotoxic when compared to the standard used i.e. Imatinib. 相似文献
94.
95.
The nucleotide sequences of the cow epsilon 2 and epsilon 4 globin genes
were determined. The sequences were 95% identical. These genes arose via a
four-gene block duplication that also gave rise to the bovine fetal (gamma)
and adult (beta) genes. Their deduced amino acid sequences are unlike any
previously reported fetal or adult globins; rather, comparison to other
mammalian globin genes indicates that they are embryonic in nature. The
sequence data indicate that these two genes have converted each other
during evolution. Pairwise comparison to the corresponding goat genes shows
greater similarity between paralogues than between more directly related
orthologues. This is in direct contrast to the situation between the cow
and goat fetal and adult genes. These observations suggest that the
frequency of DNA conversion or the fixation of conversion events may vary
in different locations of the cow beta-globin cluster.
相似文献
96.
Chromium VI Induced Structural and Ultrastructural Changes in Bush Bean Plants (Phaseolus vulgaris L.) 总被引:3,自引:0,他引:3
The effect of a growth reducing chromium VI concentration (9.6x 105M Cr as Na2CrO4) on the structure and ultrastructureof different organs of bush bean plants (Phaseolus vulgarisL.) grown on perlite was studied using light, transmission electronand scanning electron microscopy. The structural and ultrastructuralalterations observed were quite different in the various organsanalysed and did not always stay in direct relation to the averageCr content of the whole organ. The primary toxicity effect seemedto be membrane damage, due to the high oxidation power of CrVI. It is suggested that chromium is retained in vacuoles andcell walls of roots, and that the chromium reaching the leavesmay be principally Cr III and present in cell walls. The alterationsobserved in the upper plant parts seemed principally due toindirect Cr effects on the content of essential mineral nutrients. Phaseolus vulgaris L., bush bean, chromium VI toxicity, structure, ultranstructure, light microscopy, transmission electron microscopy, scanning electron microscopy 相似文献
97.
JIÍ NEDOMA PETRA PORCALOVA JAROSLAVA KOMÁRKOVÁ VOJTCH VYHNÁLEK 《Freshwater Biology》1993,30(3):369-376
- 1 Seston elemental composition (C, N, P) and the orthophosphate uptake rate constant, k(upt), were measured in the epilimnion of the eutrophic ?ímov Reservoir in the period March-August 1989.
- 2 Seasonal series of log C/P, log N/P and log [k(upt)] values were highly correlated (r2 in the range 0.84–0.93), but, based on literature-derived criteria, k(upt) values indicated stronger P deficiency than did the C/P values.
- 3 The results showed moderate to strong phosphorus deficiency in summer, moderate deficiency at the end of the spring peak of phytoplankton, and no deficiency early in the spring or during the spring clear-water period.
98.
A NOVEL method for the phosphorylation of sugars by orthophosphate in the presence of cyanogen in dilute aqueous neutral or slightly alkaline solutions has been described, suggesting a plausible model of the prebiotic phosphorylation of sugars1–3. This reaction has now been applied to the synthesis of glucose 1,6-diphosphate, starting either from α-D-glucose 1-phosphate or from D-glucose 6-phosphate. The formation of α-D-glucose 1,6-diphosphate from α-D-glucose 1-phosphate would indicate a possible route for the synthesis of this compound on the primitive Earth. It is known that α-D-glucose 1,6-diphosphate is the coenzyme in the inter-conversion of α-D-glucose 1-phosphate with glucose 6-phosphate catalysed by phosphoglucomutase*. The formation of α-D-glucose 1,6-diphosphate seems to be interesting in view of our model for the chemical evolution of the metabolism of sugars5, as it may connect α-D-glucose 1-phosphate with the glycolytic pathway. 相似文献
99.
100.