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1.
The accumulation of heavy metals in Typha latifolia L. grown in a stream carrying secondary effluent
Typha latifolia L. from aquatic plants is widely found throughout Kehli Stream (Elazig, Turkey). This study examined the uptake of some metals by T. latifolia and the transfer from roots to other plant parts. The accumulation of Mn in T. latifolia L. can be suggested as a tolerance strategy due to its transfer factor higher than 1.0. The enrichment coefficients in the leaves of T. latifolia L. were higher than 1.0 for Zn and Mn and often lower than 1.0 for other metals. Similarly, the enrichment coefficients of all metals, except for Cr, in roots of T. latifolia L. were higher than 1.0. This study demonstrated that T. latifolia L. could be considered as either a bio-indicator or a bio-accumulator for sediments and water polluted by metals. 相似文献
2.
Allopatric isolation in glacial refugia has caused differentiation and speciation in many taxa globally. In this study, we investigated the nuclear and mitochondrial genetic differentiation of the long fingered bat, Myotis capaccinii during the ice ages in south-eastern Europe and Anatolia. The mitochondrial DNA (mtDNA) analyses indicated a suture zone similar to those recorded in other animal species, including bats, suggesting the association of more than one refugium with the region. Contrary to most of the other species where a suture zone was seen in Anatolia, for M. capaccinii the geographical location of the genetic break was in south-eastern Europe. This mitochondrial differentiation was not reflected in the nuclear microsatellites, however, suggesting that the lack of contact during the ice ages did not result in reproductive isolation. Hence taxonomically, the two mitochondrial clades cannot be treated as separate species. 相似文献
3.
Zusammenfassung Die Fortpflanzungsperiode der Palmtaube (Streptopelia s. senegalensis L.) fängt in Diyarbakir/Türkei (37°55N/40°12E) schon Anfang Februar an und kann bis Mitte November dauern. In diesem Zeitraum kann ein Paar bis zu sieben Bruten beginnen (Tab. 1). Nach der Paarbildung fangen die Kopulationen an, die vor allem in der Woche vor der Eiablage stark zunehmen. Während des Brütens und der ersten Woche der Jungenaufzucht sind sie dagegen nicht zu beobachten. Sie werden vom im allgemeinen mit sog. Flügeltippen bzw. Scheinputzen eingeleitet. Nach der Begattung paradiert das um das , das auf der Stelle verharrt. Vor dem Tretakt fällt das dagegen in infantiles Verhalten und bettelt unter Flügelzittern den Partner um Futter an. Es bekommt auch tatsächlich Futter. Die Palmtauben sind zumindest für eine Fortpflanzungssaison monogam. U. a. spielen wechselseitige Gefiederpflege und Anschlußbruten sowie die Fütterung des durch das eine wichtige Rolle für das Zusammenleben und -bleiben der Partner. Der Nistplatz wird vom gezeigt, aber vom gewählt. Das Nistmaterial wird vom eingetragen und im allgemeinen vom alleine in das Nest eingefügt. Nur während des Brutwechsels bringt auch das hin und wieder Nistmaterial, das aber wahrscheinlich nur für den Partner, nicht für das Nest dient. In den späteren Phasen des Brütens gilt dies wahrscheinlich auch für das . 1–4 Tage nach dem Nestbaubeginn wird gegen Abend das erste Ei gelegt, womit auch das Brüten anfängt. Das zweite Ei folgt dann rund 38 Stunden später.
On the reproductive behaviour of the Laughing Dove (Streptopelia senegalensis): pair-formation to egg-laying
Summary In Diyarbakr/Turkey, the reproductive season of the Laughing Dove begins in early February and lasts til mid November. One pair may start with breeding up to seven times a year. The frequency of copulations which could be observed only after pair formation increased considerably in the week before incubation starts. During incubation and during the first week of the nestling period no copulations could be observed. Usually copulations are initiated by the male pecking behind its folded wings (displacement-preening). Before mating, the female turns into infantile behaviour begging food from its partner by wing-twitching. Food is then delivered by the male. After mating the female parades around the male which stays motionless. Paired birds stay together at least during one reproductive season. Reinforcement of the pair bond will be achieved by mutual preening, courtship feeding of the female by the male, and successive broods. The male indicates the nest site which is successively chosen by the female. The nest material is brought by the male and usually placed by the female at the nest site. Only during change-overs the female sometimes brings nesting material, too. However, this material probably is for the partner, not actually for the nest. The same may be true for similar behaviour of the male in late stages of incubation. One to four days after nest building has started the first egg is laid, mostly in late afternoon. Incubation starts with the first egg; the second egg is laid about 38 hours later.相似文献
4.
A new dihydroflavonol, pallasiin, together with kaempferol, quercetin, isorhamnetin, mearnsetin, aromadendrin, eriodictyol and taxifolin, has been isolated from the bark of Rhamnus pallasii and its structure elucidated as 2,3-dihydromyricetin 4′-O-methyl ether. 相似文献
5.
I. Alteraş M. D. 《Mycopathologia》1966,28(4):361-367
Summary
Trichophyton quinckeanum was isolated from a spontaneous infection in rabbit. The hairs were also invaded by the fungus, exibiting a yellowish fluorescence in Wood's light. White mice inoculation of the isolate produced typical scutula with hair penetration fluorescing in green colour. The type of animal hair invasion is also discussed. The morphologic features ofTr. quinckeanum, together with its ability of producing scutula while inoculating the white mice, must be emphasized, when proving its separate identity. 相似文献
6.
The protective effect of arbutin against potassium bromate-induced oxidative damage in the rat brain
H. Turan Akkoyun Ahmet Uyar Mahire Bayramoglu Akkoyun Aydın Şükrü Bengü Şule Melek Fatma Karagözoğlu Sevinç Aydın Suat Ekin Sinem Aslan Erdem 《Journal of biochemical and molecular toxicology》2023,37(2):e23248
This study aimed to investigate the protective effects of arbutin (ARB) against brain injury induced in rats with potassium bromate (KBrO3). The rats were divided into four groups as Group 1: Control (0.9% NaCl ml/kg/day p.), Group 2: KBrO3 (100 mg/kg (gavage), Group 3: ARB (50 mg/kg/day p.), and Group 4: KBrO3 + ARB (100 mg/kg (gavage) + 50 mg/kg/day p.). At the end of the fifth day of the study, the rats in all groups were killed, and their brain tissues were collected. In the collected brain tissues, malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) levels were measured, and routine histopathological examinations were made. The MDA levels in the group that was exposed to KBrO3 were significantly higher than those in the control group (p ˂ 0.001). In comparison to the KBrO3 group, the MDA levels in the KBrO3 + ARB group were significantly lower (p ˂ 0.001). It was observed that SOD and CAT enzyme activity levels were significantly lower in the KBrO3 group compared to the control group (p ˂ 0.001), while these levels were significantly higher in the KBrO3 + ARB group than in the KBrO3 group (p ˂ 0.001). Additionally, the group that was subjected to KBrO3 toxicity, as well as ARB administration, had much lower levels of histopathologic signs than the group that was subjected to KBrO3 toxicity only. Consequently, it was found that KBrO3 exposure led to injury in the brain tissues of the rats, and using ARB was effective in preventing this injury. 相似文献
7.
H. Yasemin Yenilmez Nazli Farajzadeh Nilgün Güler Kuşçulu Dilek Bahar Sadin Özdemir Gülşah Tollu Mithat Güllü Zehra Altuntaş Bayır 《化学与生物多样性》2023,20(4):e202201167
In this study, three new axially disubstituted silicon phthalocyanines ( SiPc1–3 ) and their quaternized phthalocyanine derivatives ( QSiPc1–3 ) were prepared and characterized. The biological properties (antioxidant, antimicrobial, antibiofilm, and microbial cell viability activities) of the water-soluble silicon phthalocyanines were examined, as well. A 1 % DMSO diluted with pure water was used as a solvent in biological activity studies. All the compounds exhibited high antioxidant activity. They displayed efficient antimicrobial and antimicrobial photodynamic therapeutic properties against various microorganisms, especially Gram (+) bacteria. Additionally, they demonstrated high antibiofilm activities against S. aureus and P. aeruginosa. In addition, 100 % bacterial reduction was obtained for all the studied phthalocyanines against E. coli viable cells. Besides, the DNA cleavage and binding features of compounds ( QSiPc1–3 ) were studied using pBR322 DNA and CT-DNA, respectively. Furthermore, the human topoisomerase I enzyme inhibition activities of compounds QSiPc1 – 3 were studied. Anticancer properties of the water-soluble compounds were investigated using cell proliferation MTT assay. They exhibited anticarcinogenic activity against the human colon cancer cell line (DLD-1). Compounds QSiPc1 and QSiPc3 displayed a high anticarcinogenic effect on the DLD-1 cell line. The obtained results indicated that all the studied compounds may be effective biological agents and anticancer drugs after further investigations. 相似文献
8.
9.
10.
The Concanavalin A agglutinating system of cell membranes. 总被引:1,自引:0,他引:1
Nejat Düzgüneş 《Bio Systems》1975,6(4):209-216
The hopes raised by the finding of differential Concanavalin A (Con A) agglutinability of normal and transformed cells in efforts to quantify differences between these cell lines seem not to have been justified. In this paper, the development of information on the mechanism of action of Con A on the cell surface, as well as the theories put forward at each stage of this development are surveyed. In this respect, investigations on Con A constitute a case history in biological research. The involvement of glycoproteins and galactosyltransferases in cell-cell interactions and their relations to Con A are also reviewed. 相似文献