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71.
Nile tilapia (Oreochromis niloticus) and silver carp (Hypophthalmichthys molitrix) held in timed-pulse feeding chambers were provided water dominated either by green algae (Scenedesmus, Ankistrodesmus and Tetraedron) or by cyanobacteria (Microcystis) to compare filtration rates (FRs). FRs were expressed as suspended particulate organic carbon (POC)/kg wet fish weight/h and as phytoplankton units filtered based on counts. Nile tilapia and silver carp filtration significantly reduced phytoplankton number of both taxonomic groups with the larger phytoplankton being filtered proportionally more than the smaller phytoplankton. Nile tilapia FR of green algae was significantly higher than silver carp; however, silver carp FR of cyanobacteria was higher than Nile tilapia. Ivlev's 90% saturation FRs (FR90) in green-algal and cyanobacterial water sources were 702 and 812 mgC/kg/h for Nile tilapia and 414 and 1028 mgC/kg/h for silver carp, respectively. Silver carp were observed to reach these FR90 values at lower POC concentrations than Nile tilapia with both green algae and cyanobacteria.  相似文献   
72.
To determine the most effective dose of arabinogalactan-protein (AGP) in regeneration medium, mature embryos of genotypes in three different ploidy levels (Triticum aestivum L. cv. Ikizce-96, Triticum durum Desf. cv. Mirzabey and Hordeum vulgare L. cv. Tokak) were used to establish an efficient plant regeneration system for cereals. Percentage of callus production, capacity of regeneration were calculated, and also culture effect, root, stem, and total plant length of regenerant plants were observed in six different regeneration media (MS control, MS+2, 5, 7, 10, 12 mg L-1 AGP) in these three different genotypes. According to the results, the highest amount of callus production was found in Ikizce-96 as 93.75% using 5 mg L-1 dicamba and 1 mg L-1 kinetin in induction medium. However, the most improved callus was observed in diploid barley Tokak as 179.95 mg in weight and 6.18 mm in diameter, respectively. The highest regeneration capacity was observed in the dose of 5 mg L-1 AGP in MS of all the genotypes and hexaploid wheat Ikizce-96 gave the best results with the highest regeneration capacity and culture effects (94.86 and 92.5%) in the same dose of AGP. These results indicated that effective dose of AGP in regeneration medium increase plant regeneration in calli derived from cereal mature embryos.  相似文献   
73.
74.
A study to determine and compare the sensitivities and specificities of the comparative cervical tuberculin (CCT) and gamma-interferon (IFN-) tests for the diagnosis of bovine tuberculosis was conducted on 30 zebu oxen. The results of the tests were compared with the presence of acid-fast bacilli found by bacteriological culturing and histopathological examinations. The sensitivity and specificity of CCT test were found to be 90.9% and 100%, respectively. Those of the commercial IFN- test were determined to be 95.5% and 87.7%, respectively. No significant differences were found between the sensitivities (Yates' corrected 2 = 0.32; p = 0.57) or the specificities (Yates' corrected 2 = 2.54; p = 0.11) of the two tests. Furthermore, a positive correlation (r = 0.76) was recorded between the increase in skin thickness following injection of bovine purified protein derivative (PPD) and the optical density in the gamma-interferon assay with bovine PPD. On the other hand, the correlation (r = 0.47) between the change in skin thickness following injection of avian PPD and the optical density in the gamma-interferon assay with avian PPD was relatively weak. On the basis of this preliminary investigation, it was concluded that the choice between the two tests depends on their cost and simplicity and on livestock management and time factors rather than on their respective diagnostic value.  相似文献   
75.
Nitric oxide (NO) has previously been shown to be responsible for nitrogen mustard (NM)-induced tissue toxicity. Excessive amounts of NO are known to be able to produce peroxynitrite, an important reactive nitrogen compound, by reacting with superoxide. Previous studies reported that NO synthase inhibitors are able to prevent NM toxicity. The aim of this study was to evaluate whether peroxynitrite is also responsible for NM-induced lung tissue damage in rats. Wistar rats were divided into four groups. NM was injected intratracheally and was treated with the selective inducible nitric oxide synthase (iNOS) inhibitor aminoguanidine (AG) (intraperitoneal) or the peroxynitrite scavenger ebselen (intragastric). Control animals were exposed to saline only. NM injection caused both oxidative and nitrosative stress, reflected by dramatically increased levels of the lipid peroxidation end product malondialdehyde (MDA), iNOS activation and urine nitrite-nitrate (NOx) values. Histopathological evaluation demonstrated lung damage with NM exposure. AG blocked iNOS activation and decreased urine NOx levels, and resulted in less histopathological changes in the lung. Although the histopathological outcome was found to be similar to AG, ebselen did not change urinary NOx or lung iNOS levels. Furthermore, ebselen was more able than AG to protect against MDA accumulation. In conclusion, the ability of ebselen to prevent against lung damage without blocking NO synthesis suggests that peroxynitrites may have an important role in the pathogenesis of NM toxicity in addition to NO.  相似文献   
76.
Mirza (Hac?zade) Gökgöl (1897–1981) was a leading agro-ecological plant scientist, agronomist and breeder in Turkey. Gökgöl carried out extensive breeding programmes extensively selecting from local plant genetic resources from across Turkey from 1925 till the 1950s. He collected and evaluated cultivars, landraces and wild relatives, predominantly of wheat, but also of barley, lentil and other crops in Turkey during 1929–1955. He published books on wheat and other cereals, potatoes, castor bean, sweet clover, poppy, and other crops. He was a hardworking pioneer utilizing wheat genetic resources for crop improvement. Since his ample work has hardly been accessible by the English-speaking scientific community today, we are providing an overview of his major work, mainly on wheat. The books he published can still be found in libraries, although with difficulties. However, his articles, leaflets etc., are hardly accessible. Some of them are: Turkish Wheats, vols. 1 and 2, Plant Breeding through Scientific Methods (1928, translation of a book by E. Baur), The Basics of Wheat Breeding (1954), and Agriculture and Breeding of Cool Season CerealsWheat, Rye, Barley, and Oats (1969). In addition to the summary of his books, we reviewed his views and discussions about the centres of origin and diversity, and compared with those of Vavilov.  相似文献   
77.
Human exposure to volatile organic compounds (VOCs) and residential indoor and outdoor VOC levels had hitherto not been investigated in Turkey. This study details investigations of indoor, outdoor, and personal exposure to VOCs conducted simultaneously in 15 homes, 10 offices and 3 schools in Kocaeli during the summer of 2006 and the winter of 2006–2007. All VOC concentrations were collected by passive sampling over a 24-h period and analyzed using thermal desorption (TD) and a gas chromatography/flame ionization detector (GC/FID). Fifteen target VOCs were investigated and included benzene, toluene, m/p-xylene, o-xylene, ethylbenzene, styrene, cyclohexane, 1,2,4-trimethylbenzene, n-heptane, n-hexane, n-decane, n-nonane, n-octane and n-undecane. Toluene levels were the highest in terms of indoor, outdoor, and personal exposure, followed by m/p-xylene, o-xylene, ethylbenzene, styrene, benzene and n-hexane. In general, personal exposure concentrations appeared to be slightly higher than indoor air concentrations. Both personal exposure and indoor concentrations were generally markedly higher than those observed outdoors. Indoor target compound concentrations were generally more strongly correlated with outdoor concentrations in the summer than in winter. Indoor/outdoor ratios of target compounds were generally greater than unity, and ranged from 0.42 to 3.03 and 0.93 to 6.12 in the summer and winter, respectively. Factor analysis, correlation analyses, indoor/outdoor ratios, microenvironment characteristics, responses to questionnaires and time activity information suggested that industry, and smoking represent the main emission sources of the VOCs investigated. Compared with the findings of earlier studies, the level of target analytes in indoor air were higher for several target VOCs, indicating a possible trend toward increased inhalation exposure to these chemicals in residential environments.  相似文献   
78.
Objective: To report a modified colostomy technique for permanent fecal diversion in calves with colonic atresia. Study Design: Prospective study. Animals: Calves (n=19) with colonic atresia. Methods: Clinical findings, white blood cell counts, radiologic, ultrasonographic, and intraoperative findings were recorded. Calves were randomly divided into 2 groups: group 1 (n=9) had conventional colostomy and group 2 (n=10) had a modified colostomy. Technique efficacy was evaluated by postoperative observation, owner satisfaction, and calf survival. Results: Fifteen (79%) calves were discharged from the hospital; 4 (21%) group 1 calves died within 24 hours after surgery. Two (40%) group 1 calves died 18 and 30 days after surgery and 5 (50%) group 2 calves died 2–60 days after surgery. Eight calves reached slaughter weight (120±10 kg); 5 group 2 calves grew normally but the 3 group 1 calves had lower weight gain. Owners of the calves with conventional colostomy reported that the evacuation of feces was continuous whereas owners of calves with the modified colostomy reported that feces were released through the stoma in intervals. Conclusion: Modification of conventional colostomy by forming an hourglass shaped stoma lessens fecal incontinence but there was no difference in survival rate. Clinical Relevance: Modified colostomy was considered advantageous because of intermittent fecal discharge from the stoma compared with continuous fecal release in conventional colostomy. The modified technique seemingly has a beneficial effect on growth of the calf.  相似文献   
79.
This study evaluated the nutritional quality of farmed and wild axillary seabream (Pagellus acarne R., 1827) focusing on amino acid profiles, with regards to possible interactions with wild fish aggregating around the cage facility. Total amino acids (∑AA), essential amino acids (∑EAA), non‐essential amino acids (∑NEAA) and neutral amino acids (∑NAA) in farmed fish were lower than those in the wild individuals (p > .05). Amino acid pattern in cage‐aggregated fish showed a slight decline from the wild populations, but still higher than the farmed fish. Based on the amino acid scores (AAS), lysine and leucine could be underlined as the ‘first limiting amino acids’, but all other AASs were over ‘1’, in accordance with reference amino acid contents of FAO/WHO (>1.00), showing that farmed axillary seabream provides high nutritional quality and can be considered as a favourable protein source. The ratios of ∑EAA/∑AA (44%–46%) and ∑EAA/∑NEAA (79%–86%) exceeded the minimum recommendation of 40% and >60% by FAO/WHO for all three groups. It can be concluded that axillary seabream either farmed, farm‐aggregated or distant wild fish presented high‐quality protein generating a healthy source for human food.  相似文献   
80.
This research was carried out to determine the effects of potassium [0, 40, 80, 120 kg potassium oxide (K2O) ha?1] and magnesium (0, 20, 40, 60 kg magnesium oxide (MgO) ha?1) applied into soil separately and together on the grain yield and yield components of sunflower for oil grown in two farmer fields in the semi-arid Central Anatolia in 2009 and 2010. The experiments were set as factorial experiment design in randomized blocks and 4 replicates. Potassium and Mg-fertilizers were used in the single time into base in the sowing. According to the results, K application in the increasing doses increased yield components more than that of Mg. Together giving of the K and Mg in certain combinations took the yield components to maximum levels. The highest grain yields were obtained by the K40Mg40 in the first year (7313 kg ha?1) and by the Mg60 in the second year (6510 kg ha?1).  相似文献   
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