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81.
82.
?smühan Poto?lu Erkara Yavuz Bülent K?se Kadir Osoydan Ersin Yücel 《Plant Systematics and Evolution》2012,298(6):1111-1117
In this study, the detailed pollen morphological structures of some endemic Turkish species of Centaurea amaena Boiss., C. antalyense H. Duman & A. Duran, C. aphrodisea Boiss., C. hierapolitana Boiss., C. luschaniana Heimerl, C. lycia Boiss., C. tossiensis Freyn. Et Sint., and C. wagenitzii Hub.-Mor. (Asteraceae, section Phaloletis) were studied under light microscopy (LM) and scanning electron microscopy (SEM) for the first time. LM and SEM investigations showed that the pollen grains of eight taxa are more or less spheroidal-subprolate, the amb triangular and tricolporate. The exine sculpture is tectate, microechinate-scabrate in the pollen of Centaurea taxa. Spinules are less dense in Centaurea amaena, C. antalyense, C. hierapolitana, and C. lycia, but they are more dense in C. aphrodisea, C. luschaniana, C. tossiensis, and C. wagenitzii. Spinule dimensions are different from each other. The exine has one layer of columellae beneath the spines. We determined all taxa that have the Helianthoid type. Exine sctructure and sculpture as well as spine density and dimensions in Asteraceae are the most reliable characteristics for discriminating taxa. 相似文献
83.
Alev?AtisEmail author Yavuz?Aydin Filiz?Ciftci Damlanur?Sak?z Abdullah?Arslan Ak?n?S?Toklu Melahat?Donmez Nimet?Goker 《Reproductive biology and endocrinology : RB&E》2012,10(1):11
Background
In this study, we investigated the effect of hyperbaric oxygen therapy (HBOT) on the morphology of estradiol valerate (EV) induced polycystic ovary (PCO) to find a new treatment modality for improvement of PCO. 相似文献84.
Gecit İ Kavak S Meral I Güneş M Pirinççi N Sayir F Demir H Ceylan K 《Cell biochemistry and function》2012,30(4):303-308
This study was designed to investigate whether the short-term extracorporeal shockwave lithotripsy (ESWL) exposure to kidney produces an oxidative stress and a change in some trace element levels in liver and diaphragm muscles of rats. Twelve male Wistar albino rats were divided randomly into two groups, each consisting of six rats. The animals in the first group did not receive any treatment and served as control group. The right-side kidneys of animals in group 2 were treated with two-thousand 18 kV shock waves while anesthetized with 50 mg kg(-1) ketamine. The localization of the right kidney was achieved after contrast medium injection through a tail vein under fluoroscopy control. The animals were killed 72 h after the ESWL treatment, and liver and diaphragm muscles were harvested for the determination of tissue oxidative stress and trace element levels. Although the malondialdehyde level increased, superoxide dismutase and glutathione peroxidase enzyme activities decreased in the livers and diaphragm muscles of ESWL-treated rats. Although glutathione level increased in liver, it decreased in diaphragm muscles of ESWL-treated animals. Fe, Mg and Mn levels decreased, and Cu and Pb levels increased in the livers of ESWL-treated animals. Fe and Cu levels increased, and Mg, Pb, Mn and Zn levels decreased in the diaphragm muscles of ESWL-treated animals. It also causes a decrease or increase in many mineral levels in liver and diaphragm muscles, which is an undesirable condition for the normal physiological function of tissues. 相似文献
85.
In this study, we aimed to investigate the distribution pattern of ubiquitin and p97/VCP in the rat retina during postnatal
development. Eyeballs from 1-, 4-, 10-, 36- and 72-week-old rats were examined by immunohistochemistry, and protein colocalization
was determined by immunofluorescence microscopy. In the 1-week-old rat retina, p97/VCP was strongly expressed in the neuroblast
layer, however no ubiquitin immunoreactivity was observed. p97/VCP immunoreactivity was present in the ganglion cell layer
(GCL), inner nuclear layer (INL), outer nuclear layer (ONL), inner segment (IS) of the photoreceptor layer, and retinal pigment
epithelium in the 4- and 10-week-old rat retinas. p97/VCP immunoreactivity increased significantly in the 10-week-old rat
retinas. Ubiquitin was barely seen in the 4-week-old rat retinas, and ubiquitin expression was weak in the GCL and the IPL
of the 10-week-old rat retinas. In the 36- and 72-week-old rats, the presence of ubiquitin was remarkable in the IS, INL,
IPL and GCL, however, p97/VCP immunoreactivity was significantly decreased. Colocalization of ubiquitin and p97/VCP was also
observed in the INL, IS, GCL and ONL of 36- and 72-week-old rat retinas. Our results indicate that p97/VCP immunoreactivity
in the retina significantly decreases after rats reach 10 weeks of age, whereas ubiquitin immunoreactivity increases with
aging. These results suggest that an altered expression pattern of p97/VCP and ubiquitin in the developing rat retina may
associate with age-related retinal degeneration. 相似文献
86.
Walckenaeria aksoyi sp. n. (Araneae: Linyphiidae) is described based on males from Marmaris Province in Turkey. 相似文献
87.
Lale Donbak Eyyup Rencuzogullar Ayse Yavuz Mehmet Topaktas 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2005,588(2):82-87
A cytogenetic monitoring study was carried out on a group of workers from a bituminous coal mine in Zonguldak province of Turkey, to investigate the genotoxic risk of occupational exposure to coal mine dust. Cytogenetic analysis, namely sister chromatid exchanges (SCEs), chromosomal aberrations (CAs) and micronucleus (MN) tests were performed on a strictly selected group of 39 workers and compared to 34 controls matched for gender, age, and habit. Smoking and age were considered as modulating factors. Both SCE and CA frequencies in coal miners appeared significantly higher than in controls. Similarly, there was a significant increase in the frequency of total micronuclei in exposed group as compared to control group. The effect of smoking on the level of SCE and MN was significant in the control group. A positive correlation between the age and the level of SCE was also found in controls. The frequencies of both SCE and CA were significantly enhanced with the years of exposure. The results of this study demonstrated that occupational exposure to coal mine dust leads to a significant induction of cytogenetic damage in peripheral lymphocytes of workers engaged in underground coal mining. 相似文献
88.
Phyto/zooplankton composition, chlorophyll a, and some water quality parameters were investigated in a spring-originated pond in Central Anatolia between February 2001
and January 2002. Water temperature, pH, dissolved oxygen, Secchi depth, total and calcium hardness, nitrate-nitrogen, nitrite-nitrogen,
ammonia-nitrogen, total phosphorus, and soluble reactive phosphorus levels were analyzed. A total of 49 species belonging
to Bacillariophyceae, Chlorophyceae, Cyanophyceae, Cryptophyceae, and Dinophyceae were identified. The highest phytoplankton
abundance was found in August, whereas the lowest was determined in January. Phytoplankton abundance increased from February
to August and declined in the following months. The Bacillariophyceae were dominant in the phytoplankton community. A total
of 21 species of Rotifera, 2 species of Cladocera, and 1 genus of Copepoda were found. The zooplankton community was dominated
by Rotifera. The highest abundance of zooplankton was recorded in July and the lowest value in November. The annual mean concentration
of chlorophyll a was measured as 1.90 μg l−1. In spite of these eutrophic levels (mean values of total phosphorus and nitrate-nitrogen: 0.069 mg P l−1 and 0.68 mg N l−1), phytoplankton cannot grow satisfactorily because of the short water retention time (0.6 day−1). The shallowness of the pond together with the low phytoplankton biomass and the high concentrations of nutrients are discussed. 相似文献
89.
Elif Yavuz Hatice Gunes Sebnem Harsa Cisem Bulut A. Fazil yenidunya 《World journal of microbiology & biotechnology》2004,20(8):871-874
Although thermophilic members of the genus Bacillus are known to tolerate extreme environmental conditions, they appeared to be readily damaged upon mechanical manipulations. This fact was evidenced in genotyping of some strains of thermophilic Bacillus by pulsed field gel electrophoresis (PFGE). Consequently, a new procedure for the preparation of agarose plugs was developed. The procedure produced interpretable genomic DNA restriction profiles. 相似文献
90.
A total of 190 Campylobacter spp. isolates, of which 34 gave the result of very weak activity, and 156 gave the negative activity in the test for hippurate
hydrolysis were characterized. The genomic DNA was isolated from a fresh culture of each isolate and the real-time PCR, targeting
the hipO gene, was used to confirm the species distribution of Campylobacter isolates. The hipO gene was detected in 17 isolates (11%) within the total of 156 negative isolates for hippurate hydrolysis. Out of 34 isolates
with very weak activity, 19 isolates (56%) were also found to be positive for hipO gene and characterized as C. jejuni. The real-time PCR assay used in this study could be employed for more accurate diagnosis of Campylobacter infections at species level after the biochemical characterization based on hippuricase activity of the isolates. This could
also provide important data for the epidemiology of infections associated with these zoonotic pathogens. 相似文献