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41.
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   
42.
Staphylococcus aureus in home environments may serve as a reservoir for human colonization, making sampling of indoor surfaces relevant to exposure assessment. Using laboratory experiments and application to homes of asthmatic children in Barbados, we characterize microbiological methods adapted for settings with transportation delays between sampling and initiation of culture.  相似文献   
43.

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   
44.
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   
45.
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   
46.
We have analyzed 7,137 samples from 125 different caste, tribal and religious groups of India and 99 samples from three populations of Nepal for the length variation in the COII/tRNA(Lys) region of mtDNA. Samples showing length variation were subjected to detailed phylogenetic analysis based on HVS-I and informative coding region sequence variation. The overall frequencies of the 9-bp deletion and insertion variants in South Asia were 1.9 and 0.6%, respectively. We have also defined a novel deep-rooting haplogroup M43 and identified the rare haplogroup H14 in Indian populations carrying the 9-bp deletion by complete mtDNA sequencing. Moreover, we redefined haplogroup M6 and dissected it into two well-defined subclades. The presence of haplogroups F1 and B5a in Uttar Pradesh suggests minor maternal contribution from Southeast Asia to Northern India. The occurrence of haplogroup F1 in the Nepalese sample implies that Nepal might have served as a bridge for the flow of eastern lineages to India. The presence of R6 in the Nepalese, on the other hand, suggests that the gene flow between India and Nepal has been reciprocal.  相似文献   
47.
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   
48.
The use of maize microsatellite markers as a potential cost-effective method for molecular analysis of sugarcane was evaluated. Of the 34 primer pairs obtained from maize genomic libraries, 14 showed repeatable amplifications in Saccharum species clones, commercial hybrids, and the related genera Erianthus, accounting for 41.17% cross transferability. Complex banding patterns were encountered in sugarcane with the number of amplified fragments ranging from 7 to 14 with an average of 10 per primer, indicating the high polyploidy and heterozygosity existing in sugarcane. Phenetic analysis of the SSR polymorphisms produced by nine primers could clearly differentiate the different species of Saccharum and Erianthus and revealed the relationships that existed between them. Genetic similarity co-efficient indicated low diversity existing among the S. officinarum clones (82%) and a relatively higher level of diversity in the S. spontaneum clones (69.7%). Higher level of divergence of Erianthus from Saccharum was also clearly estabilished. Five primers produced genus- and species-specific fragments for Erianthus, S. spontaneum, S. officinarum, and S. barberi. The polymorphic primers, when tested on a panel of 30 commercial sugarcane cultivars, revealed a broad range (32.4-83.3%) of pair-wise similarity values, indicating their ability to detect high levels of polymorphism. A combination of two primers could differentiate all the varieties, further emphasizing their potential in fingerprinting and varietal identification.  相似文献   
49.
Nonenzymatic glycation of tissue and plasma proteins may stimulate the production of oxidant and carbonyl stress in diabetes. The aim of this study was to evaluate the effects of aminoguanidine (AG) on lipid peroxidation, protein oxidation and nitric oxide (NO) release in diabetic rat kidneys. After induction of diabetes with streptozotocin, female Wistar rats were divided into 2 groups. Group DAG (n=9) rats were given AG hydrogen carbonate (1 g/L) in drinking water and group D (n=8) was diabetic control rats given only tap water. Group H (n=8) was followed as healthy controls. At the end of an 8 week period, NO release, lipid and protein oxidation were determined in kidney tissues. NO release was significantly lower in diabetic rats compared with healthy controls (p<0.05). Lipid peroxidation was significantly high in group D (3.9 ± 0.3 nmol MDA/g tissue) compared with the group DAG (2.6 ± 0.1 nmol MDA/g tissue, p<0.01) and group H (2.4 ± 0.2 nmol MDA/g tissue). Protein oxidation was significantly higher in diabetics than healthy controls (563.8 ± 23.9, 655.8 ± 7.2 , 431.5 ± 8.8 mmol carbonyl / g tissue for group DAG, D and H, respectively, p< 0.05). A positive correlation between albuminuria and thiobarbituric acid reactive substance (TBARS) levels (r= 0.54,p<0.005) and carbonyl content (r=0.70, p<0.0005) in kidney homogenate were observed. Although AG treatment had no effect on NO release, it significantly decreased lipid peroxidation in diabetic rat cortices. Consequently increased lipid peroxidation -as well as- protein oxidation could be involved in the pathogenesis of diabetic albuminuria.  相似文献   
50.
Poly(2-hydroxyethylmethacrylate) (pHEMA) based flat sheet membrane was prepared by UV-initiated photopolymerization technique. The membrane was then grafted with -histidine. Catalase immobilization onto the membrane from aqueous solutions containing different amounts of catalase at different pH was investigated in a batch system. The maximum catalase immobilization capacity of the pHEMA–histidine membrane was 86 μg cm−2. The activity yield was decreased with the increase of the enzyme loading. It was observed that there was a significant change between Vmax value of the free catalase and Vmax value of the adsorbed catalase on the pHEMA–histidine membrane. The Km value of the immobilized enzyme was higher 1.5 times than that of the free enzyme. Optimum operational temperature was 5°C higher than that of the free enzyme and was significantly broader. It was observed that enzyme could be repeatedly adsorbed and desorbed without loss of adsorption capacity or enzyme activity.  相似文献   
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