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1.
The present study was undertaken to determine in vivo and in vitro effects of some plant growth regulators on rat erythrocyte carbonic anhydrase (CA) and glucose-6-phosphate dehydrogenase (G6PD) activities. Both in vivo and in vitro, spermidine and kinetin did not affect enzymatic activities of CA and G6PD, whereas putrescine decreased these activities, and abscisic acid increased them. Since plants use such growth regulators, their effects should be considered on mammals consuming them since they may possess important biological effects.  相似文献   
2.
The changes in fatty acid compositions during nutritional interaction among almond Amygdalus communis Linnaeus (Rosales: Rosaceae) (host plant), lacebug Monosteria unicostata (Mulsant and Rey) (Heteroptera: Tingidae) and its predator Piocoris luridus Fieber (Heteroptera: Lygaeidae) were determined by gas chromatography and gas chromatography-mass spectrometry analyses. The fatty acid profiles of phospholipids and triacylglycerols were substantially different. Unlike the general observations for virtually most terrestrial insects, arachidonic and eicosapentaenoic acids were detected in high proportions of phospholipid fractions in both insects, especially in P. luridus. Also the almond tissues provide very little oleic acid to the herbivore diet, yet both insect species developed high proportions of this component. Our data reveals instances of specific accumulation of fatty acid biosynthesis, elongation/desaturation, and not incorporating selected fatty acids into cellular lipids.  相似文献   
3.
The object was to determine the influence of dietary vitamin E, selenium and their combination on the fatty acid con-tent of erythrocytes, bone marrow and spleen lipids of Akkaraman lambs. After supplementation for 15 days, the amount of all fatty acids was slightly higher (p < 0·05) in the vitamin E as compared to the control group, whereas the amount of longer fatty acids was significantly higher (p < 0·01, p < 0·001) in the selenium and combination groups. On the thirtieth day, the amount of all fatty acids was slightly high (p < 0·5) in all the supplemented groups in comparison with the control group. In the bone marrow lipids, the amount of longer fatty acids was decreased (p < 0·05, p < 0·01, p < 0·001) in the vitamin E and combination groups as compared to the control. Although the amount of some fatty acids was high (p < 0·05, p < 0·01) in the selenium group compared to the control, linoleic (18:2), linolenic (18:3) and the polyunsaturated fatty acids (PUFA) were lower (p < 0·05, p < 0·001). In the spleen lipids, the amount of longer fatty acids was slightly decreased (p < 0·05) in the vitamin E group as compared with the control; however the amount of longer fatty acids was significantly higher (p < 0·05, p < 0·01) in the selenium and combination groups in comparison to the control group. Thus dietary supplementation with selenium was more effective than dietary vitamin E supplementation in altering the fatty acid content of the erythrocyte, bone marrow and spleen lipids. © 1997 John Wiley & Sons, Ltd.  相似文献   
4.

Background

Several methods to cultivate limbal epithelial stem cells (LESCs) in vitro with the support of feeder layers and different growth medium formulations have been established for several years. The initial green medium consists of various ingredients that exhibit a non-optimal level of biosafety, therefore, different modifications have been made to suit it to safe clinical applications. However, the question of which formulation is the most appropriate remains to be answered.

Aims

This study evaluated the outgrowth kinetics and stemness of cells cultured from human limbal explants with the aim of preserving LESC characteristics in the human-derived platelet-rich fibrin (HPRF)–conditioned medium with no feeder cell layer or carrier for the first time. The final composition of the cell culture system included only human-derived products without any xenobiotic or chemical substances to minimize the potential risk for human health, which will be useful for clinical purposes.

Methods

To test our hypothesis, limbal explants were incubated with either Dulbecco's Modified Eagle's Medium (DMEM)/F12-10% human serum (HS), human-derived amniotic membrane (HAM)-conditioned DMEM/F12-10% HS or HPRF-conditioned DMEM/F12-10% HS to determine whether outgrowth kinetics and stemness of cells show any differences among groups.

Results

The results showed that the HPRF-conditioned medium showed higher concentration levels of growth factors, which may be involved in the promotion of LESC expansion while preserving the stem cell characteristics. HPRF-conditioned medium had significantly superior capacity to enhance the cell growth rate, the stem/progenitor cell phenotype and the expressions of putative stem cell markers.

Conclusion

This novel xeno-feeder-chemical-free, completely human-derived and biologically safe culture system including HPRF and HS would be of interest to replace conventional cell culture strategies to meet safety requirements mandatory for clinical use in humans.  相似文献   
5.
Astragalus bahcesarayensis H. Akan, M. Fırat & M. Ekici (Leguminosae-Papilionoideae) from Turkey is described and illustrated. It is compared with A. dipsaceus Bunge and A. panduratus Bunge. The geographical distributions of the new species and related species are mapped.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 439–444.  相似文献   
6.
The effects of foliar sprays of gibberellic acid (GA) on thegrowth of tomato plants cv. Potentate were studied in growthrooms and a glasshouse. Four sprays of GA (5 ppm) increasedleaf area and whole plant weight relative to water controlsgrown at constant temperatures (7, 17, 22, and 27 °C) for12 days, the largest plants being obtained with 5 ppm. Experimentsmade at four photoperiods (5, 10, 15, and 20 h) and at two lightintensities (7000 and 10 750 lx) showed that GA increased leafand whole plant weight at 15 h, leaf area at 10 and 15 h andstem height at all photoperiods; area, height, and weight increaseswere obtained at both light intensities, leaf growth being increasedmore by GA at 7000 lx and stem growth more at 10 750 lx. Four foliar sprays of GA (5 ppm) were combined with N supplementsapplied via leaf and/or root to plants in sand culture. Withlow supply to the roots (20 ppm N) GA failed to increase growth,but increased it at higher levels. Total N in leaf and stemwas increased by GA or by NH4NO3 (10 sprays 280 ppm N) at alllevels of N supplied to roots, but when applied together theeffect on total leaf N was more than additive except at thehighest level (540 ppm) GA increased the concentration of N(as per cent dry matter) in leaf and stem at all levels of Nsupplied to roots. GA and NH4NO3 together resulted in a greateramount and a higher concentration of N in the shoots (and usuallyalso in roots) than did NH4NO3 alone. Leaf thickness (as freshweight/unit area) could only be increased appreciably by sprayingwith a complete nutrient solution which reduced leaf area butnot dry weight. Growth increases induced by GA were detectable 43 days afterthe first of four sprays in the glasshouse and after 30 daysin the growth room. The persistence of GA effects was comparedwith those induced by sprays of NH4NO3.  相似文献   
7.
Previous allozyme and DNA nucleotide sequence studies of the mealybug genus Ferrisia Fullaway (Hemiptera: Pseudococcidae), although limited, have suggested greater species diversity than is recognized by the current morphology‐based taxonomy. Here we analyse nucleotide sequence data from one mitochondrial (cytochrome oxidase I) and two nuclear (EF‐1α and 28S D2D3) genes and recover ten well‐supported groups that allow us to reassess the taxonomic utility of morphological characters used for species recognition. We report on previously used morphological characters for which states are highly variable within genetic groups and identify new characters (of the wax‐exuding cuticular ducts and pores) with taxonomically informative states. The widespread pest species F. virgata (Cockerell), commonly called the striped mealybug, should be diagnosed more narrowly. From samples identified as F. virgata, we recover six clades that we equate with species and that can be distinguished with the newly identified morphological characters. We determine that five of the ‘electrophoretic species' identified informally by the late Uzi Nur based on electrophoretic mobility of 20 enzymes correlate with four of our genetic groups. This matching of Nur's putative species with ours was possible only because some of Nur's slide‐mounted voucher specimens were deposited in a museum and thus available for morphological study. Species confused with F. virgata are either new to science or were placed erroneously in synonymy with F. virgata by earlier authors: they will be described elsewhere. The most important characters of the adult female for distinguishing these species from F. virgata are the positions and characteristics of minute discoidal pore(s) associated both with the ventral oral‐collar tubular ducts and with the sclerotized area surrounding each dorsal enlarged tubular duct, and the number of sizes of the ventral oral‐collar tubular ducts. In addition, we determine that adult females of F. gilli Gullan from different populations on different host plants vary substantially in the number and size of clusters of small ventral oral‐collar ducts on the body margins – features previously suspected to indicate distinct species.  相似文献   
8.
Ferula mervynii M. Sağıroğlu & H.Duman, sp. nov. from north-east Anatolia in Turkey (A8: Artvin & Erzurum) is described and illustrated. It is closely related to F. coskunii H.Duman & M.Sağıroğlu, from which it differs mainly in its habit, basal leaves, umbel, and mericarp features. Diagnostic morphological characters are discussed. Notes are also presented on its ecology and conservation status, together with scanning electron micrographs of the surface of the mericarps and of a somatic metaphase plate showing the chromosome number.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 357–362.  相似文献   
9.
Ferula coskunii H. Duman & M. Sağıroğlu sp. nov. from the Amanos Mountains (C6: Hatay-Turkey) is described and illustrated. It is closely related to F. drudeana Korovin, from which it differs mainly in habit, basal leaves, stem and mericarp features.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 357–361.  相似文献   
10.
Although differential selective pressures on males and females of the same species may result in sex‐specific evolutionary trajectories, comparative studies of adaptive radiations have largely neglected within‐species variation. In this study, we explore the potential effects of natural selection, sexual selection, or a combination of both, on bite performance in males and females of 19 species of Liolaemus lizards. More specifically, we study the evolution of bite performance, and compare evolutionary relationships between the variation in head morphology, bite performance, ecological variation and sexual dimorphism between males and females. Our results suggest that in male Liolaemus, the variation in bite force is at least partly explained by the variation in the degree of sexual dimorphism in head width (i.e. our estimate of the intensity of sexual selection), and neither bite force nor the morphological variables were correlated with diet (i.e. our proxy for natural selection). On the contrary, in females, the variation in bite force and head size can, to a certain extent, be explained by variation in diet. These results suggest that whereas in males, sexual selection seems to be operating on bite performance, in the case of females, natural selection seems to be the most likely and most important selective pressure driving the variation in head size. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 461–475.  相似文献   
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