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101.
The teleostean immune system is variable between and within taxa in terms of morphology. Accordingly, in the current study, the histology of some immune organs (thymus, kidney and spleen) of Lake Van fish (Alburnus tarichi) was investigated. For this purpose, the tissues from eight mature fish were fixed and embedded in paraffin wax, and then the sections were stained with haematoxylin and eosin, Mallory’s triple, periodic acid-Schiff and Alcian blue (pH of 2.5) for histologic examinations. In the thymus, no clear discrimination of the cortex and medulla was observed. Lymphoid cells within a reticulo-epithelial network were the predominant cell type in the thymus. The other components in the thymus were macrophages and myoid, mast-like, plasma-like, cystic cells, Hassall’s corpuscles, and single or multiple epithelial cystic structures. In the kidney, the head kidney, a major haematopoietic site, consisted of lymphoid and non-lymphoid zones within a reticular network. Cells exhibiting mitotic figures were also detected in the haematopoietic tissue of the head kidney. Haematopoietic tissue was also found in the trunk kidney dispersed amongst the excretory components. The spleen was composed of red and white pulp. The red pulp comprised abundant erythrocytes, whilst the white pulp contained leucocytes with a reticular network. Ellipsoids were also determined in the white pulp. Melanomacrophage centres were found in all of the examined lymphoid tissues of the fish. These findings, which were reported, herein, for the first time will provide reference knowledge for future studies of this anadromous fish.  相似文献   
102.
This analysis measures trade-offs between soil loss and food production costs. It is made by means of multigoal interregional programming model. The trade-off curve is derived by means of the prior weighing technique. The results indicate that soil loss from agricultural land can be decreased considerably with very little increase in costs and decrease in efficiency in food production. However, the trade-off curve has a ‘corner’ in it, and further reductions in soil loss give rise to sharp increases in food production costs. As higher costs are assigned soil loss, important shifts take place in the interregional patterns of crop production and land use. Also, further decreases in soil loss and increases in food production costs raise food prices for consumers.  相似文献   
103.
Sorption of anionic surfactants Aerosol-OT (AOT) and Sodium Dodecyl Sulfate (SDS), as well as cationic surfactant Hyamine1622 on two soil surfaces were investigated. Batch equilibriumtechniques were used under laboratory conditions to observe the amount of surfactant adsorbed and desorbed to and from thesoil surfaces. Data obtained were fitted to two sorption isotherms in order to characterise the sorption process. The nature of the sorbate (i.e. the surfactant) was found to be important in the sorption process. Anionics adsorbed via hydrophobic bonding, whereas `cation-exchange' mechanism was dominant in the sorption of cationic Hyamine 1622. Anionic AOT,with a double chain, and hence a higher critical packing parameter, adsorbed more strongly onto the surface compared tothe singly-chained SDS.  相似文献   
104.
Horses, donkeys, and mules have been important in Turkey for agriculture, transport, and the military for hundreds of years. Equids number more than 0.5 million in Turkey. Most horses are local types but emphasis is now on Thoroughbreds and Arabians for racing and competitions. New roles have not materialized for donkeys and mules that continue to perform their traditional activities. Disease control is assured mainly by public services acting within laws governing diseases and welfare. African horse sickness, glanders, dourine, equine infectious anemia, vesicular stomatitis, equine encephalomyelitis, anthrax, and rabies are notifiable diseases but none of the mainly equine diseases has been reported in Turkey for many years. Several zoonoses, including toxoplasmosis, brucellosis, listeriosis, and Rhodococcus infections, have been identified by serodiagnosis over wide areas, but animals carrying antibodies rarely exhibit clinical symptoms. Among other diseases in Turkish Equidae are piroplasmosis, respiratory infections, contagious equine metritis and equine influenza. Other viral and bacterial pathogens have been identified in isolated investigations. Internal and external parasites are a major cause of economic loss. Much research on equine diseases has been undertaken in the last decade of the 20th and first decade of the 21st centuries, perhaps because of Turkey's possible accession to the European Union and the goal to harmonize identification and control procedures and also because of the country's increasing participation in international equine events. This paper reviews animal health services and provides a bibliography of more than 100 references covering horse, donkey, and mule diseases in Turkey.  相似文献   
105.
During 2003 and 2005, plant growth promoting effects of two Bacillus strains OSU-142 (N2-fixing) and M3 (N2-fixing and phosphate solubilizing) were tested alone or in combinations on organically grown primocane fruiting raspberry (cv. Heritage) plants in terms of yield, growth, nutrient composition of leaves and variation of soil nutrient element composition in the province of Erzurum, Turkey. The results showed that Bacillus M3 treatment stimulated plant growth and resulted in significant yield increase. Inoculation of raspberry plant roots and rhizosphere with M3 and/or OSU-142 + M3, significantly increased yield (33.9% and 74.9%), cane length (13.6% and 15.0%), number of cluster per cane (25.4% and 28.7%) and number of berries per cane (25.1% and 36.0%) compared with the control, respectively. In addition, N, P and Ca contents of raspberry leaves with OSU-142 + M3 treatment, and Fe and Mn contents of the leaves of raspberry with M3 and OSU-142 + M3 applications significantly improved under organic growing conditions. Bacterial applications also significantly effected soil total N, available P, K, Ca, Mg, Fe, Mn, Zn contents and pH. Available P contents in soil was determined to be increased from 1.55 kg P2O5/da at the beginning of the study to 2.83 kg P2O5/da by OSU-142, to 5.36 kg P2O5/da by M3 and to 4.71 kg P2O5/da by OSU-142 + M3 treatments. The results of this study suggest that Bacillus M3 alone or in combination with Bacillus OSU-142 have the potential to increase the yield, growth and nutrition of raspberry plant under organic growing conditions.  相似文献   
106.
Turkey is an important producer of cornelian cherries (Cornus mas L.), especially in northern Anatolia. Seed propagation and long-term human selection has given rise to a great diversity of trees. Twenty-six cornelian cherry genotypes (CC1–CC26) from the Coruh Valley in northern Anatolia were evaluated for genetic relationships by using Randomly Amplified Polymorphic DNA (RAPD) markers, based on 56 decamer random primers, seven of which showed reliable polymorphisms. These seven primers generated 80 markers, with 77 (96.25%) displaying polymorphisms. Cluster analysis of the cornelian cherry genotypes was performed based on data from polymorphic RAPD bands, by using Jaccard’s similarity coefficient and the Unweighted pair-group method with arithmetic average (UPGMA) clustering method. A similarity matrix showed that the highest genetic similarity (0.913) was between CC15 and CC16 and the least (0.129) was between CC4 and CC16. The cophenetic correlation coefficient between the similarity matrix and the cophenetic matrix of the dendrogram was relatively high (r = 0.87), supporting the validity of the dendrogram. Based on these results, RAPD analysis can be used for the characterization and grouping of cornelian cherry genotypes. Genetically divergent genotypes identified in this study may be useful for future breeding programs. This is the first study demonstrating that RAPD analyses can be used to differentiate and classify cornelian cherry genotypes.  相似文献   
107.
The aim of this study is to determine the effect of levamisole and levamisole-trichlorfon combination on isolated sheep trachea. Contraction was achieved with levamisole concentrations (10(-8)-10(-3) M) on tracheal strips of adult sheep (> 1 year of age). Pretreatment with trichlorfon (10(-7) M)-levamisole (10(-7) M) decreased the pD2 and E(max) of Ach when compared to levamisole pretreatment (p < or = 0.01). Pretreatment with levamisole (10(-7) M), decreased the E(max) (p < or = 0.01) and pD2 (p < 0.05) of bethanechol concentrations (10(-8)-10(-3) M) significantly. Pretreatment with atropine (10(-6) M) decreased the E(max) of levamisole (10(-4) M) significantly (p < 0.05). To conclude, levamisole acted mainly on the muscarinic receptors of the sheep trachea and this effect was partly inhibited by atropine. Adverse interaction was present between levamisole and trichlorfon.  相似文献   
108.
Weed control is a major concern for organic farmers around the world and non-chemical weed control methods are now the subject of many investigations. Field studies were conducted in tomato (Solanum lycopersicum L.) from 2004 to 2006 at the Black Sea Agricultural Research Institute experiment field to determine the weed suppressive effects of winter cover crops. Treatments consisted of ryegrass (Lolium multiflorum L.), oat (Avena sativa L.), rye (Secale cereale L.), wheat (Triticum aestivum L.), gelemen clover (Trifolium meneghinianum Clem.), Egyptian clover (Trifolium alexandrinum L.), common vetch (Vicia sativa L.), hairy vetch (Vicia villosa Roth.) and a control with no cover crop. Treatments were arranged in a randomized complete block design with four replications. To determine the weed suppressive effects of the cover crops, weed density and total weed dry biomass were assessed at 14, 28, and 56 days after termination (DAT) of the cover crops from all plots using a 50 × 50 cm quadrat placed randomly in each plot. After cover crop kill and incorporation into soil, tomato seedlings variety ‘H2274’ were transplanted. Broadleaved weed species were the most prominent species in both years. Total weed biomass measured just prior to cover crop incorporation into the soil was significantly lower in S. cereale plots than in the others. The number of weed species was lowest at 14 DAT and later increased at 28 and 56 DAT, and subsequently remained constant during harvest. This research indicates that cover crops such as L. multiflorum, S. cereale, V. sativa and V. villosa could be used in integrated weed management programs to manage some weeds in the early growth stages of organic tomato.  相似文献   
109.
Liriomyza cicerina (Diptera: Agromyzidae) is an important pest on chickpea in Turkey. The objective of this study was to determine the parasitoids and rates of parasitism ofL. cicerina on chickpea (Cicer arietinum L.) during the 2005 and 2006 seasons in ?anl?urfa province, Turkey. Leaves with mines were sampled weekly and kept in the laboratory to observe and count emerging leafminer and parasitoid adults. Eight parasitoid species were collected: the braconidsOpius monilicornis Fischer andOpius tersus Foerster and the eulophidsDiaulinopsis arenaria (Erdös) andNeochrysocharis formosa (Westwood), which occurred in both the winter and summer seasons;Diglyphus crassinervis Erdös,Neochrysocharis ambitiosa Hansson,Neochrysocharis sericea (Erdös) andPediobius metallicus (Nees), which occurred only in the summer growing areas.Diaulinopsis arenaria was the predominant parasitoid with 4–7.7% parasitism rate whileN. ambitiosa andO. monilicornis were the second and third most predominant species. The results of these trials show that sinceDia. arenaria occurred throughout every season, it could potentially be used for control of the leafminerL. cicerina.  相似文献   
110.
Avena sativa L. (Poaceae) has been reported to have traditional utilization against skin diseases and inflammation. Therefore, in this study, the n-hexane, ethyl acetate, ethanol, and water extracts of A. sativa were investigated for their wound healing and antioxidant activities. Total phenol and flavonoid contents of the extracts were established spectrophotometrically. For the wound healing activity, linear incision and circular excision models on rats and mice were evaluated with a standard ointment Madecassol®. Antioxidant activity was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferrous ion-chelating, and ferric-reducing antioxidant power (FRAP) assays. Significant wound healing activity was observed with the ointment formulation of the ethanol extract at 1% concentration. The histopathological examination results also supported the outcome of both linear incision and circular excision wound models. All of the extracts exerted low antioxidant activity in the applied assays. The present study provides a scientific evidence for the traditional usage of A. sativa in the management of wound healing.  相似文献   
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