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41.
A highly sensitive, simple and rapid spectrofluorimetric method was developed for the determination of lacidipine (LCP) in tablets. The proposed method is based on the investigation of the fluorescence spectral behavior of LCP in both sodium dodecyl sulphate (SDS) and the tween‐80 micellar system. In aqueous solutions of acetate buffer (pH 4.5), the fluorescence intensities of LCP were greatly enhanced (ca. 2.4 and 4.3 folds) in the presence of either SDS or tween‐80, respectively. The fluorescence intensity was measured at 444 nm after excitation at 277 nm using either SDS or tween‐80 as a surfactant. The fluorescence–concentration plots were rectilinear over the ranges of 50.0–500.0 ng/ml and 5.0–200.0 ng/ml with lower detection limits of 5.11 and 2.06 ng/ml and lower quantification limits of 17 and 6.87 ng/ml using SDS and tween‐80, respectively. The method was successfully applied to the analysis of LCP in commercial tablets and the results were in good agreement with those obtained with the comparison method. Furthermore, content uniformity testing of pharmaceutical tablets was also conducted. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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Shoot apices of Spinacia oleracea plants have been induced toflower either by: (a) subjecting leaves to 24 h long day, or(b) exposure to a short photoperiod but displaced by 8 h (displacedshort day) in the usual 24 h short-day cycle, or (c) exposureto low temperature (5 °C) during the dark period of thenormal short day. A quantitative cytochemical assay of pentosephosphate pathway activity during floral induction indicatesan approximate doubling of the rate of activity when comparedto that of vegetative apices (short day) (21 °C). Exposure to either low temperature, or a displaced short photoperiodstimulates pentose phosphate pathway activity in the shoot apexin a manner similar to that seen by long-day induction. Thischange in metabolic activity is accompanied by changes in theshape of the shoot apex which resembles that seen at an earlystage during floral induction. Spinacia oleracea, pentose phosphate pathway, shoot apex, glucose-6-phosphate dehydrogenase, floral induction, chilling, displaced short day  相似文献   
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Cell-penetrating peptides (CPPs) are membrane permeable vectors recognized for their intrinsic ability to gain access to the cell interior. The hydrophobic counter-anion, pyrenebutyrate, enhances cellular uptake of oligoarginine CPPs. To elucidate CPP uptake mechanisms, the effect of pyrenebutyrate on well-recognized CPPs with varying hydrophobicity and arginine content is investigated. The cellular CPP uptake and CPP-mediated oligonucleotide delivery is analyzed by fluorescence activated cell sorting, confocal microscopy, and a cell-based splice-switching assay. The splice-switching oligonucleotide is a mixmer of 2′-O-methyl RNA and locked nucleic acids delivered as a non-covalent complex with 10-fold molar CPP excess. CPP-induced membrane perturbation on large unilamellar vesicles is investigated in calcein release experiments. We observed that pyrenebutyrate facilitates cellular uptake and translocation of oligonucleotide mediated by oligoarginine nonamer while limited effect of pyrenebutyrate on more hydrophobic CPPs was observed. By combining the different experimental results we conclude that the pathway for cellular uptake of oligoarginine is dominated by direct membrane translocation, whereas the pathway for oligoarginine-mediated oligonucleotide translocation is dominated by endocytosis. Both mechanisms are promoted by pyrenebutyrate and we suggest that pyrenebutyrate has different sites of action for the two uptake and translocation mechanisms.  相似文献   
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The total antioxidant activity (TAA) and the accumulation of small heat shock proteins (sHsps) were analysed under field conditions in Quercus ilex with regard to organ ontogeny and the physiological state of the plant. The results point toward the participation of sHsps and an increase of TAA in the general adaptation syndrome (GAS) of woody Mediterranean evergreens. In leaves and stems, there was a definite TAA seasonal pattern but no effect from diurnal variations or from the current stage of organ ontogeny. TAA was about twice as large in summer as in spring and winter and the hydrophilic antioxidant content was about 16 times greater than that of lipophilic antioxidants. The accumulation of sHsps in leaves also showed a seasonal pattern, but no effect from diurnal variations or from leaf ontogeny. In summer days, the sHsps content remained invariable even during the daylight hours in which the leaves were physiologically recovered. However, the accumulation of sHsps in stems did vary in relation to organ ontogeny. Old stems had a high accumulation of sHsps throughout the year, whereas in young stems, accumulation of sHsps was detected only in summer. This is probably due to a higher quantity of lignified and suberized tissues in the older stems. Using two‐dimensional immunodetection for leaves and stems, two sets of Hs protein species (17 and 10 kDa regions) were observed. In stems, there was an increase in 10 kDa proteins from winter to summer. These results are discussed and the possible role of the two types of polypeptides in the face of environmental and endogenous oxidative stress are considered.  相似文献   
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Biology Bulletin - Erodium glaucophyllum, Erodium hirtum and Erodium guttatum were medicinal herbs from a southern Mediterranean known for its health benefits. There is a strong demand for the find...  相似文献   
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Abstract: Among the new dental remains from the late Early Eocene of Chambi (Kasserine area, Tunisia) is a large‐sized upper molar of a new bat species, Witwatia sigei nov. sp. (Chiroptera, Vespertilionoidea, Philisidae), described herein. The locality of Chambi has revealed evidence for an early appearance of two modern microchiropteran superfamilies in Africa: Dizzya exsultans, a Philisidae, which is considered to be an archaic Vespertilionoidea, and an indeterminate Rhinolophoidea. In addition to D. exsultans, the new species, W. sigei, is the second representative of the Philisidae in this locality. W. sigei extends back to the late Early Eocene the occurrence of the genus Witwatia, which was previously only reported from the early Late Eocene of the Fayum (BQ‐2, Egypt). By analogy with the largest extant microbats, the large size of Witwatia suggests a tendency to the opportunistic diet of this taxon, thereby contrasting with the strict insectivory characterizing primitive bats found in other continents in the same epoch.  相似文献   
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Jach, R., Machaniec, E. & Uchman, A. 2011: The trace fossil Nummipera eocenica from the Tatra Mountains, Poland: morphology and palaeoenvironmental implications. Lethaia, Vol. 45, pp. 342–355. The tubular trace fossil Nummipera eocenica Hölder 1989 occurs in a single stratigraphical horizon in Eocene nummulitic limestones of the Tatra Mountains, Poland. The wall of N. eocenica is built of Discocyclina and Nummulities (larger foraminifera) tests, very rarely of the Ditrupa (Polychaeta) tube fragments, bivalve shell fragments, echinoid spines and coralline algae. Morphotype are distinguished on the basis of wall composition and structure. Morphotype A is dominated by fusiform Discocyclina tests, which were preferentially selected by the trace makers for construction of a well‐constructed and resistant wall. Morphotype B contains more robust tests of Nummulites, while morphotype C is dominated by saddle‐shaped tests of Discocyclina. Nummipera eocenica was produced during a period of seafloor stabilization caused by a deepening. The succession of the morphotypes B, A reflects diminishing energy and increasing water depth. Probably morphotype C represents even lower energy environment than morphotype A. The trace fossil is interpreted as a domichnion, which wall was constructed for protection. The trace maker can be considered between polychaetes and crustaceans; however, comparisons to the closest recent analogues, the polychaete Diopatra cuprea or alpheid shrimps, are not satisfactory. □Bartonian, burrow, Carpathians, large foraminifera, trace fossils.  相似文献   
50.
Ginger is used as one of the important ingredients in traditional as well as modern medicine besides as a spice. It boosts immunity and is a rich source of many biologically active substances and minerals. Although it is a medicinally important crop, its productivity is, however, affected due to poor nutrient management and therefore it requires an adequate supply of nutrients in the form of inorganic fertilizers or organic manuring, or a mixture of both. In this context, the present study was aimed to investigate the effect of mineral fertilizers on the content of mineral elements in the ginger rhizome, on soil enzyme activity, and soil properties. Lysimeter experiments were conducted at the Institute of Genetics and Plant Experimental Biology, Kibray, Tashkent region, Uzbekistan. The experiment comprised of four treatments T1 – Control, T2 - N75P50K50 kg/ha, T3 - and T4 - N100P75K75 + B3Zn6Fe6 kg/ha. The results showed that the application of N125P100K100 kg/ha increased rhizome K content by 49%, P content by 20%, and Na content by 58% as compared to control without fertilizer. While the application of N100P75K75 + B3Zn6Fe6 kg/ha showed a significant enhancement in rhizome K, Ca, P, Mg, Na, Fe, Mn, Zn, Cu, Cr, Mo, and Si contents over the control. This treatment also improved active P content by 29%, total P content by 80%, total K content 16%, and N content by 33% content, and the activities of urease, invertase, and catalase activities as compared to control of without mineral fertilizer and control respectively. Thus the application of NPK + BZnFe at the rate of 100:75:75:3:6:6 kg/ha helps in improving macroelements and microelements in the ginger rhizome and activities of soil enzymes that helps in mineral nutrition of the rhizome.  相似文献   
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