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41.
42.
The frequency of antibiotic resistance was compared inAeromonas spp. isolated from fresh and brackish water in Southern Turkey. A total of 97Aeromonas spp. strains were isolated from four zones (three from fresh and one from brackish water). Most of the strains isolated from all samples wereAeromonas hydrophila (79.4%), while the amount ofAeromonas sobria andAeromons caviae, were rather lower in the samples examined (17.5% and 3.1% respectively). A high proportion of isolates from all water sources showed resistance to cephalotin (86.6%) and trimethoprim-sulphamethoxazole (69%). On the other hand, a low proportion of bacteria showed resistance to tetracycline (14.4%), chloramphenicol (11.3%), gentamicin (7.2%) and nitrofurantoin (6.8%). Only one strain showing resistance to amikacin was found. Multiple Antibiotic Resistance Index (MARI) to at least two antibiotics was highest in brackish water (zone 4), followed by fresh water (zone 3). MARI values ranging from 0.2 to 0.8 for the bacteria isolated from brackish water. This study suggest that, multiple antibiotic resistantAeromonas spp., especiallyA. hydrophila, can be easily recovered from fresh and brackish water sources in Turkey and these sources may play as a reservoirs responsible for disease pathogen aeromonads. 相似文献
43.
Priya Ravikumar Cuneyt Yilmaz D Merrill Dane Robert L Johnson Aaron S Estrera Connie C W Hsia 《Journal of applied physiology》2007,102(3):1170-1177
Mechanical forces imposed on lung tissue constitute major stimuli for normal lung development and postpneumonectomy (PNX) compensatory growth and remodeling. Superimposing developmental signals on PNX signals augments compensatory alveolar growth but exaggerates airway-parenchymal dissociation (i.e., dysanaptic lung growth); the latter tends to offset benefits derived from the former. In adult dogs after PNX, lobar expansion and growth of the remaining lobes were markedly non-uniform (Ravikumar et al. J Appl Physiol 97:1567-1574, 2004). We hypothesized that superimposing developmental and post-PNX signals further accentuates nonuniformity of lobar growth. We used high-resolution computed tomography (HRCT) to follow regional lung expansion and growth in foxhounds undergoing right PNX at 2.5 mo of age compared with litter-matched control (Sham) animals; scans were performed 4 and 10 mo following surgery, i.e., before and after somatic maturity. Air and tissue volumes were measured in each lobe; tissue volume estimated by HRCT includes air-free tissue and blood in small vessels <1 mm. Interlobar nonuniformity of tissue volume was absent at 4 mo but evident 10 mo after PNX; growth of the remaining left lower lobe gradually lagged behind other lobes. At maturity, nonuniformity of lobar growth in pneumonectomized puppies was similar to that previously reported in pneumonectomized adults. We conclude that superimposing developmental and post-PNX signals enhances some aspects of compensatory lung growth and remodeling without altering its nonuniform spatial distribution. 相似文献
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45.
Davut Turan Cüneyt Kaya Gökhan Kalayci Esra Bayçelebi İsmail Aksu 《Journal of fish biology》2019,94(3):458-468
Oxynoemacheilus cemali sp. nov. is described from the Çoruh River drainage in the eastern Black Sea basin. One molecular marker (coI), 25 morphometric and four meristic characters were analysed. Oxynoemacheilus cemali is distinguished from O. kosswigi, O. banarescui, O. samanticus and O. angorae in the Black Sea basin by having a suborbital groove in males, an axillary lobe at the pelvic-fin base, no dorsal adipose crest on the caudal peduncle, a slightly-forked caudal fin and 7–15 dark grey dorsal saddles. Morever, Oxynoemacheilus cemali is distinguished by commonly having 9–15 irregularly-shaped dark-grey bars on the flank posterior to the dorsal-fin origin or, rarely having a mottled pattern or 4–6 irregularly shaped dark-grey bars on the flank posterior to the dorsal-fin origin. Oxynoemacheilus cemali is also distinguished from the closely related species O. araxensis and O. cyri, distributed outside the Black Sea basin, by having 15 and 31 diagnostic nucleotide substitutions in the coI barcode region, respectively. 相似文献
46.
The use of biological means for ground improvement have become popular, which generally works through the process called microbially-induced calcium carbonate precipitation (MICP). Many studies indicate successful application of MICP based improvement with multiple bacteria and on several soils. Given the proven performance of MICP, this study aims to examine the MICP process by comparing the calcium carbonate precipitation ability of widely studied bacteria, i.e., Sporosarcina pasteurii and relatively under-recognized bacteria, i.e., Bacillus licheniformis to outline the formation success. For this purpose, two different sands were tested for observing precipitation behavior using a series of syringe tests. Furthermore, the effect of concentration and inclusion of calcium chloride for nutrition of bacteria, saturation with water, and hybrid use of two bacteria were investigated in some tests for diversification. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive x-ray spectroscopy (EDS) were used for the interpretation of results. Results indicated that Sporosarcina pasteurii had performed superior over Bacillus licheniformis when achieving calcium carbonate precipitation in tests for both sands. In addition, many intriguing SEM images contributed to the literature of MICP monitoring, highlighting the effects of the variables investigated. 相似文献
47.
Assessment of DNA strand breakage by comet assay in diabetic patients and the role of antioxidant supplementation 总被引:7,自引:0,他引:7
Diabetes patients often show increased production of reactive oxidative species (ROS) together with vascular complications. The presence of these ROS may lead to increased DNA damage in peripheral blood lymphocytes that may be revealed by the comet assay. To test whether DNA is damaged in diabetes, peripheral blood samples were taken from 30 control individuals and 63 diabetic patients (15 insulin dependent (IDDM) and 48 non-insulin dependent (NIDDM)) and the alkaline comet assay was used to evaluate background levels of DNA damage. Significant differences were detected between control and diabetic patients in terms of frequencies of damaged cells. The extend of DNA migration was greater in NIDDM patients by comparison with IDDM patients which might indicate that IDDM patients are handling more oxidative damage on a regular basis. Smoker individuals had higher frequencies of cells with migration by comparison with the non-smokers in both groups. Also, clear differences between patients on placebo and on Vitamin E supplementation for 12 weeks were observed on the basis of the extend of DNA migration during single cell gel electrophoresis. 相似文献
48.
We investigated the effect of PON 55 and PON 192 polymorphisms on serum PON1 activity and lipid profiles in 213 non-insulin dependent diabetes mellitus (NIDDM) individuals and 116 non-diabetic controls among Turkish subjects. The distribution of PON 55/192 gene polymorphism was determined by polymerase chain reaction-based restriction fragment length polymorphism. Serum lipid levels were measured enzymically. PON activity was measured by spectrophotometric assay of p-nitrophenol production following addition of paraoxon. We found that PON 55 and 192 genotype distribution was similar in patients and controls and paraoxonase activity was generally lower in diabetics than in control subjects. We showed that PON 55 and 192 genotypes have a major effect on serum PON activity. PON 192 BB homozygotes had significantly higher PON activity than AA and AB genotypes among the control and NIDDM populations (p<0.001). PON 55 MM homozygotes had significantly lower PON activity than did LL and LM genotypes in control and NIDDM populations (p<0.05). The PON1 55 and 192 polymorphisms did not consistently influence the serum lipid profiles in either population. In conclusion, our results suggest that the paraoxonase activities are affected by PON1 genetic variability in Turkish NIDDM patients and controls. 相似文献
49.
Yilmaz HR Songur A Ozyurt B Zararsiz I Sarsilmaz M 《Prostaglandins, leukotrienes, and essential fatty acids》2004,71(2):131-135
In this experimental study, the effect of fish n-3 fatty acids was studied on the some important enzymes of carbohydrate metabolism, hexokinase (HK), glucose-6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD), lactate dehydrogenase (LDH), and malate dehydrogenase (MDH) in rat liver. Wistar albino rats of experimental group (n= 9) were supplemented fish omega-3 fatty acids (n-3 PUFA) as 0.4 g/kg bw. by gavage for 30 days in addition to their normal diet. Isotonic solution was given to the control group (n= 8) by the same way. At 30th day, the rats were killed by decapitation under ether anesthesia, autopsied and liver was removed. Spectrophotometric methods were used to determine the activities of above-mentioned enzymes in the liver. The n-3 PUFA caused increases in the activities of HK, G6PD, LDH, and MDH in comparison with control. These increases were statistically significant (P < 0.01) except 6PGD activity. As a result, n-3 PUFA may regulate the metabolic function of liver effectively by increasing HK, G6PD, 6PGD, LDH, and MDH enzyme activities of rat liver when added in enough amounts to the regular diet. 相似文献
50.