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1.
Summary Growth chamber experiments with sunflower in nutrient solution were performed to investigate the effect of phosphorus and bicarbonate in inducing iron chlorosis.Iron chlorosis as proved by lower dry matter yield and reduced chlorophyll content was induced by bicarbonate alone and more pronounced by a combination of bicarbonate and phosphate, but not by phosphate alone.Iron content of roots and aerial plant parts was reduced by bicarbonate in all experiments, but only in one experiment by phosphate alone.Bicarbonate in the nutrient medium increased the pH of the cytoplasm in leaf cells, while phosphate had no effect.A daily adjustment of the pH in the nutrient medium to a value comparable to that in the bicarbonate trial, did not affect the pH of the cytoplasm.It is concluded that the pH of the cytoplasm plays an important role in establishing plant resistance or susceptibility to Fe chlorosis.  相似文献   
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International Journal of Biometeorology - Epidemiological studies have suggested an association between particulate air pollution, increased temperatures, and morbidity related to pregnancy...  相似文献   
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A new series of 6, 7-dihydroxy-3-(methylphenyl) chromenones, including three new derivatives, i.e. 6,7-dihydroxy-3-(2-methylphenyl)-2H-chromen-2-one (OPC); 6,7-dihydroxy-3-(3-methylphenyl)-2H-chromen-2-one (MPC); 6,7-dihydroxy-3-(4-methylphenyl)-2H-chromen-2-one (PPC) and one previously described, namely 6,7-dihydroxy-3-phenyl-2H-chromen-2-one (DPC), were synthesized. These compounds were investigated as inhibitors of human carbonic anhydrase I (hCA-I) and human carbonic anhydrase II (hCA-II) which had been purified from human erythrocytes on an affinity gel comprised of L-tyrosine-sulfonamide-Sepharose 4B.  相似文献   
4.
The enzyme carbonic anhydrase (E.C. 4.2.1.1) has a stimulatory effect on glaucoma, an eye disease that has a risk to dogs, which are models for the human eye disease, that is similar to that in humans.

In this study, some sulfonamide derivatives, 2-(3-cyclohexene-1-carbamido)-1,3,4-thiadiazole-5-sulfonamide (CCTS), 4-(3-cyclohexene-1-carbamido) methyl-benzenesulfonamide (CCBS), 2-(9-octadecenoylamido)-1,3,4-thiadiazole-5-sulfonamide (ODTS), 2-(4,7,10-trioxa-tetradecanoylamido)-1,3,4-thiadiazole-5-sulfonamide (TDTS), and 2-(8-methoxycoumarine-3-carbamido)-1,3,4-thiadiazole-5-sulfonamide (MCTS), as well as some anionic compounds (perchlorate and chloride) and existing medicines (dorzolamide-HCl, gentamicine sulphate, tropicamide, and procaine-HCl) were assayed for their inhibition of dog carbonic anhydrase (dCA), which was purified from erythrocytes on an affinity gel of L-tyrosine-sulfonamide-Sepharose 4B. ODTS showed the highest potency amongst the synthetic compounds with IC50 value 1.18 × 10? 5 M. Amongst the medicines tested, only dorzolamide showed inhibition with IC50 value 5.05 × 10? 4 M. Procaine and tropicamide actually showed an activatory effect, whereas gentamicine sulfate had no significant effect. The inhibitory effects of anionic compounds such as perchlorate and chloride were also investigated; whereas perchlorate showed inhibition, chloride did not.  相似文献   
5.
The present article is a taxonomic study of all spongy spumellarian radiolarian taxa with three and four coplanar spines or spongy arms occurring in the middle Carnian from the Köseyahya section, near the town of Elbistan, SE Turkey. This fauna is characteristic of the Tetraporobrachia haeckeli radiolarian Zone, and comes from an 8 m thick succession of clayey-cherty limestones occurring at the lower part of the section. In addition, a few species from the Middle and Upper Triassic from other areas have been also included in this study to improve some generic diagnoses, and to better comprehend the diversity and evolutionary trends of some genera, subfamilies and families. The taxonomy at the generic and suprageneric levels is based primarily on the types of microsphere. This new approach allowed new taxonomic arrangements of genera and suprageneric units, and suggested new phylogenetic relationships among these radiolarians and between them and younger radiolarians. The authors discuss and describe 69 species, of which 37 are new, and 14 genera, of which three are new (Paraparonaella, Pseudangulobracchia, and Ropanaella). The genus Triassoastrum and others are reinterpreted. All genera studied are assigned to five subfamilies, of which two are new (Tetrapaurinellinae and Triassocrucellinae), and two families (Tritrabidae and Veghicycliidae). Nine species in open nomenclature are also illustrated.  相似文献   
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The genus Centaurea L. is one of the largest and important genera of Asteraceae family. Centaurea species have been widely used as herbal remedies in folk medicine for their antidandruff, antidiarrheic, antirheumatic, anti‐inflammatory, choleretic, diuretic, digestive, stomachic, astringent, antipyretic, cytotoxic, and antibacterial properties. Centaurea baseri Kose & Alan is a recently described local endemic species in Turkey and this is the first study on the chemical composition and bioactivity of its hydrodistilled essential oil and the crude extract. According to chromatospectral analysis, hexadecanoic acid (42.3%), nonacosane (8.2%), and heptacosane (8.0%) were the main compounds of the essential oil, while 16 compounds were determined in the MeOH extract using LC/MS. Furthermore, antimicrobial, antioxidant, and cytotoxic effects of the essential oil and the extract were evaluated in comparison with the standard agents. The extract showed strong antifungal effect against Candida utilis at the concentration of 60 μg/ml (MIC) where the EO showed growth inhibition at the concentration of 47.00 μg/ml (MIC) against pathogen Bacillus cereus. Both the essential oil and the extract did not show any selective antioxidant properties. The extract showed remarkably selective cytotoxic properties against MCF‐7, PANC‐1, A549, and C6 glioma cells.  相似文献   
9.
New secondary benzenesulphonamide-substituted coumarylthiazole derivatives were synthesized and their inhibitory effects on purified carbonic anhydrase I and II were evaluated using CO2 as a substrate. The result showed that all the synthesized compounds exhibited inhibitory activity on both hCA I and hCA II with N-(4-(2-oxo-2H-chromen-3-yl)thiazol-2-yl)naphthalene-2-sulphonamide (5f, IC50 value of 5.63 and 8.48?µM, against hCA I and hCA II, respectively) as the strongest inhibitor revealed from this study. Structure–activity relationship revealed that the inhibitory activity of the synthesized compounds is related to the type of the halogen and bulky substituent on the phenyl ring. In addition, the cupric reducing antioxidant capacities (CUPRAC) and ABTS cation radical scavenging abilities of the synthesized compounds were assayed. 4-methoxy-N-(4-(2-oxo-2H-chromen-3-yl)thiazol-2-yl)benzenesulphonamide (5e) exhibited the strongest ABTS and CUPRAC activity with IC50 value of 48.83?µM and A0.50 value of 23.29?µM, respectively.  相似文献   
10.
The purpose of this study was to investigate the anti-hyaluronidase activities of honeys from different botanical origins honeys in order to determine their anti-inflammatory properties. The total phenolic contents, total flavonoids and total tannin levels of six types of honey, chestnut, oak, heather, pine, buckwheat and mixed blossom, were determined. Concentration-related inhibition values were tested turbidimetrically on bovine testis hyaluronidase (BTHase) as IC50 (mg/mL). All honeys exhibited various concentration-dependent degrees of inhibition against BTHase. Inhibition values varied significantly depending on honeys’ levels of phenolic contents, flavonoid and tannin. The honeys with the highest anti-hyaluronidase activity were oak, chestnut and heather. In conclusion, polyphenol-rich honeys have high anti-hyaluronidase activity, and these honeys have high protective and complementary potential against hyaluronidase-induced anti-inflammatory failures.  相似文献   
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