Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

TÜBİTAK

Discipline
Keyword
Publication Year
Publication

Articles 9631 - 9660 of 10500

Full-Text Articles in Entire DC Network

Cover And Contents Jan 2003

Cover And Contents

Turkish Journal of Veterinary & Animal Sciences

No abstract provided.


Identification Of Common Aspergillus Species, Ahmet Asan Jan 2003

Identification Of Common Aspergillus Species, Ahmet Asan

Turkish Journal of Botany

No abstract provided.


Cover And Contents Jan 2003

Cover And Contents

Turkish Journal of Botany

No abstract provided.


Pioneering Biotechnological Works On Hordeum Vulgare L. Cvs Performed In Collaboration With The İstanbul University Biology Department And The Tübi̇tak Research Institute For Genetic Engineering And Biotechnology, Nermi̇n Gözükirmizi Jan 2003

Pioneering Biotechnological Works On Hordeum Vulgare L. Cvs Performed In Collaboration With The İstanbul University Biology Department And The Tübi̇tak Research Institute For Genetic Engineering And Biotechnology, Nermi̇n Gözükirmizi

Turkish Journal of Botany

Hordeum vulgare L. (barley) is an important cereal crop and is also an excellent model organism for biochemists, physiologists, geneticists and molecular biologists. H. vulgare cvs. have been used as a model system for almost 30 years at the Biology Department of İstanbul University, İstanbul-Turkey. The first studies on experimental mutagenesis were followed by tissue culture, gene transfers, DNA marker applications and finally DNA arrays which, progressed further after the 1990 when collaboration was established with the Plant Biotechnology group at the TÜBİTAK Research Institute for Genetic Engineering and Biotechnology in Gebze, Kocaeli-Turkey. This review article outlines the results of …


Cover And Contents Jan 2003

Cover And Contents

Turkish Journal of Botany

No abstract provided.


Cover And Contents Jan 2003

Cover And Contents

Turkish Journal of Botany

No abstract provided.


Correlation And Path Coefficient Analysis For Some Yield-Related Traits In Rice (Oryza Sativa L.) Under Thrace Conditions, Hali̇l Sürek, Necmi̇ Beşer Jan 2003

Correlation And Path Coefficient Analysis For Some Yield-Related Traits In Rice (Oryza Sativa L.) Under Thrace Conditions, Hali̇l Sürek, Necmi̇ Beşer

Turkish Journal of Agriculture and Forestry

The associations among yield components, and their direct and indirect influence on the grain yield of rice were investigated. For this purpose, 80 breeding lines derived from 11 different cross populations in the F_6 generation and their 10 parents were tested in a randomised complete block experiment design with two replications at the Thrace Agricultural Research Institute in 1995. According to the results from the first year, 49 breeding lines were selected, and they and their 10 parents were tested in a randomised complete block experiment design with three replications in the same institute in 1996. The phenotypic correlations among …


Cover And Contents Jan 2003

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Determining The Strength Properties Of The Dixired Peach Variety, Kubi̇lay K. Vursavuş, Faruk Özgüven Jan 2003

Determining The Strength Properties Of The Dixired Peach Variety, Kubi̇lay K. Vursavuş, Faruk Özgüven

Turkish Journal of Agriculture and Forestry

Peaches, like other fruits, are susceptible to different kinds of damage during and after harvest. Such damage is a major cause of quality loss in fruit. In order to reduce these losses, it is necessary to know the strength properties of fruit. Some strength properties of "Dixred" peaches are investigated in this paper. Peaches were stored at 0 ºC and 90% relative humidity for specified lengths of time. Impact treatment was applied by a pendulum impactor at four energy levels. Bruise volume was measured in the bruised peaches after impact, and bruise susceptibility was calculated from the linear regression line …


Improving The Mass Rearing Possibilities Of Serangium Montazerii Fürsch (Coleoptera: Coccinellidae) On Different Host Plants Of Bemisia Tabaci (Genn.) (Homoptera: Aleyrodidae), Gonca Vatansever, M. Rifat Ulusoy, Lerzan Bakircioğlu Erkiliç Jan 2003

Improving The Mass Rearing Possibilities Of Serangium Montazerii Fürsch (Coleoptera: Coccinellidae) On Different Host Plants Of Bemisia Tabaci (Genn.) (Homoptera: Aleyrodidae), Gonca Vatansever, M. Rifat Ulusoy, Lerzan Bakircioğlu Erkiliç

Turkish Journal of Agriculture and Forestry

The objectives of this study were to identify suitable plant species for mass rearing and to determine some biological characteristics of the predator Serangium montazerii Fürsch (Coleoptera: Coccinellidae) used in the biological control of Dialeurodes citri (Ashmead) (Homoptera: Aleyrodidae). The development time, mortality rate, preoviposition, oviposition and postoviposition periods and fecundity of S. montazerii were studied on various host plants using Bemisia tabaci (Genn.) (Homoptera: Aleyrodidae). Two cotton (Çukurova-1518 and Deltapine) and two eggplant (Pala and Çukurova topağı) cultivars were used at 25 ºC and 65 ± 5% RH in growth chambers. Additionally, life tables were constructed from the data …


Cover And Contents Jan 2003

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Electrophoretic Aspects Of Blood Serum Proteins Of The Genus Apodemus In The Black Sea Region, Reyhan Çolak Jan 2002

Electrophoretic Aspects Of Blood Serum Proteins Of The Genus Apodemus In The Black Sea Region, Reyhan Çolak

Turkish Journal of Biology

Globulin and albumin proteins of Apodemus populations in the Black Sea region were examined using SDS-PAGE (sodium dodecyl sulphate - polyacrylamide gel electrophoresis). There were 7-11 bands in the globulin region and 1-3 bands in the prealbumin zone. It was determined that there were variations in both the globulin region and the prealbumin zone in populations of this genus. A band was observed in the postalbumin zone with different electrophoretic mobilities including slow and fast. This different mobility in the postalbumin zone separated Apodemus specimens into two different populations in sympatry. These findings showed that at least two populations of …


Partial Purification Of Intestinal Triglyceride Lipase From Cyprinion Macrostomus Heckel, 1843 And Effect Of Ph On Enzyme Activity, Naci̇ Değerli̇, M. Ali̇ Akpinar Jan 2002

Partial Purification Of Intestinal Triglyceride Lipase From Cyprinion Macrostomus Heckel, 1843 And Effect Of Ph On Enzyme Activity, Naci̇ Değerli̇, M. Ali̇ Akpinar

Turkish Journal of Biology

Intestinal triglyceride lipase (TG) of Cyprinion macrostomus after precipitation with 30% polyethylene glycol (PEG), was partially purified by hydrophobic interaction chromatography on phenyl sepharose CL-4B, and the effect of pH on this enzyme activity was determined titrimetrically. Intestinal tissue homogenates were precipitated using 30% PEG-8000, and then applied onto a phenyl sepharose CL-4B column for hy-drophobic interaction chromatography. The lipase that bound to this hydrophobic resin and was partially purified by this single step application was then eluted from this resin with taurocholic acid and Triton X-100 elution. This purified enzyme effectively hydrolysed natural olive oil substrate under the experimental …


Hydroxyurea Induces P53 Accumulation And Apoptosis In Human Cervical Carcinoma Cells, Hakan Akça, Osman Ni̇dai̇ Özeş Jan 2002

Hydroxyurea Induces P53 Accumulation And Apoptosis In Human Cervical Carcinoma Cells, Hakan Akça, Osman Ni̇dai̇ Özeş

Turkish Journal of Biology

Cervical carcinoma is one type of cancer with a high mortality rate in women. In this research, we investigated the cytotoxic, antiproliferative and apoptosis-inducing effects of hydroxyurea on a human cervical carcinoma cell line, HeLa. We found that hydroxyurea has cytotoxic and antiproliferative effects on HeLa cells in a dose-dependent manner. We also found that hydroxyurea can increase cellular levels of p53 and p21, and induce DNA fragmentation in a dose-dependent manner. We concluded that the observed antiproliferative, cytotoxic and apoptosis inducing activities of hydroxyurea might be mediated by the induction of p53 and its transcriptional target, p21.


Analysis Of The Effects Of Hyperosmotic Stress On The Derepression Of Invertase Activities And The Growth Of Different Baker's Yeast Strains, Sezai̇ Türkel, Tülay Turgut Jan 2002

Analysis Of The Effects Of Hyperosmotic Stress On The Derepression Of Invertase Activities And The Growth Of Different Baker's Yeast Strains, Sezai̇ Türkel, Tülay Turgut

Turkish Journal of Biology

The growth of baker's yeast Saccharomyces cerevisiae in medium containing sucrose requires a high level of extracellular invertase enzyme activity. However, the expression of invertase is under the strict control of glucose repression in S. cerevisiae. In addition, invertase enzyme activity is also affected by physiological stress conditions that baker's yeast is exposed to during the various stages of industrial level production and downstream processing. We analyzed the effect of hyperosmotic stress on the derepression of invertase activities of a haploid laboratory yeast strain and three different industrial baker's yeast strains. Our results indicated that hyperosmotic stress interferes with the …


Effect Of Experimental Diabetes Mellitus On Plasma Lactate Dehydrogenase And Glutamic Oxaloacetic Transaminase Levels In Rabbits, İsmai̇l Çeli̇k, Eşref Yeği̇n, Fehmi̇ Odabaşoğlu Jan 2002

Effect Of Experimental Diabetes Mellitus On Plasma Lactate Dehydrogenase And Glutamic Oxaloacetic Transaminase Levels In Rabbits, İsmai̇l Çeli̇k, Eşref Yeği̇n, Fehmi̇ Odabaşoğlu

Turkish Journal of Biology

Hyperglycemia was induced in 20 male, white, New Zealand rabbits (2-3 kg) (Oryctolagus cuniculus huxley) by alloxan (100 mg/kg body weight, I.V.) and maintained for 16 weeks without insulin treatment. Blood samples were taken from both diabetic and non-diabetic rabbits at the same time for measurement of plasma enzymes. Levels of glutamic oxalacetic transaminase (GOT) and lactate dehydrogenase (LDH) were determined after treatment. The levels of LDH and GOT were 155.6 ± 41.9 U/L and 47.0 ± 20.4 U/L in the control group respectively. These parameters were 286.9 ± 142.9 U/L and 93.9 ± 62.5 U/L in the diabetic group …


Protoplast Fusion In Sugar Beet (Beta Vulgaris L.), Songül Gürel, Ekrem Gürel, Zeki̇ Kaya Jan 2002

Protoplast Fusion In Sugar Beet (Beta Vulgaris L.), Songül Gürel, Ekrem Gürel, Zeki̇ Kaya

Turkish Journal of Biology

In this study, attempts were made to fuse the suspension-derived protoplasts of a sugar beet breeding line (ÇBM315) with the mesophyll-derived protoplasts of three breeding lines (M114, ELK345 and M1017), which were obtained from our previous experiments. Combinations of three different PEG concentrations (20%, 25% or 30%) and three different treatment durations (15, 20 or 25 min) were tested. The fusion efficiency was determined by measuring the viability, heterokaryon frequency and plating efficiency (PE) of the fused protoplasts after four weeks of culture. In general, 25% PEG combined with 20 min treatment duration produced the highest fusion frequency, but the …


Accumulation Of Poly-\Beta-Hydroxybutyrate In Streptomyces Species During Growth With Different Nitrogen Sources, Aysel Uğur, Nuretti̇n Şahi̇n, Yavuz Beyatli Jan 2002

Accumulation Of Poly-\Beta-Hydroxybutyrate In Streptomyces Species During Growth With Different Nitrogen Sources, Aysel Uğur, Nuretti̇n Şahi̇n, Yavuz Beyatli

Turkish Journal of Biology

The accumulation of poly-\beta-hydroxybutyric acid (PHB) in 27 Streptomyces isolates with different taxonomical properties was investigated. The amount of synthesized PHB was determined as crotonic acid by spectrophotometry. Eighty percent of the tested isolates accumulated PHB between 0.3 and 7.6% of dry mycelial weight. PHB was produced by a selectant of Streptomyces isolates in media containing different nitrogen sources (KNO_3, glycine, peptone, proteose peptone, L-asparagine, tryptone and malt extract), each combined with 2 g/l glucose as the carbon source. The most effective PHB production was observed on glycine/glucose medium with a 7.6% dry mycelial weight. Nitrogen limiting conditions were inhibitory …


Embryo Culture In Barley (Hordeum Vulgare L.), Betül Bürün, Esi̇n Çoban Poyrazoğlu Jan 2002

Embryo Culture In Barley (Hordeum Vulgare L.), Betül Bürün, Esi̇n Çoban Poyrazoğlu

Turkish Journal of Biology

The effects of medium and sterilization on the mature embryo culture of barley (Hordeum vulgare L.) were studied. Among the different media used, the highest plantlet development from embryos was obtained in Randolph and Cox medium (92.1%), followed by Murashige and Skoog (MS) (91.3%), half-strength MS (1/2 MS) (87.7%) and B5 (85.7%). Among the sterilization methods studied, sodium hypochlorite sterilization followed by treatment of antibiotic solution and sterilization HgCl_2 application was found to be more effective than the other methods. However, no statistically significant negative effect of HgCl_2 on the plantlet development from embryos was observed.


Alkaliphilic Micro-Organisms And Habitats, Zeynep Ulukanli, Meti̇n Diğrak Jan 2002

Alkaliphilic Micro-Organisms And Habitats, Zeynep Ulukanli, Meti̇n Diğrak

Turkish Journal of Biology

Alkaline environments are typical extreme environments which include naturally occurring soda lakes, deserts, soils and artificially occurring industrial-derived waters. Micro-organisms that occupy extreme pH environments have resulted in the definition of an unusual group, termed alkaliphiles. In this review, the current status of the biodiversity of alkaliphilic micro-organisms in various environments and aspects of their biotechnological potential are summarised briefly.


Purification And Determination Of The Molecular Structure Of Hemolymph Lectin Of Agrotis Segetum (Denis And Schiff.), Nursel Gül, Cevat Ayvali Jan 2002

Purification And Determination Of The Molecular Structure Of Hemolymph Lectin Of Agrotis Segetum (Denis And Schiff.), Nursel Gül, Cevat Ayvali

Turkish Journal of Biology

A soluble lectin was purified from the hemolymph of Agrotis segetum by two methods, via affinity chromatography on a Sepharose-4B column and gel filtration on a Superdex-200 column. Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) showed a single protein band with a molecular weight of 69,000 in both the presence and absence of 2-Mercaptoethanol. Alternatively, the molecular weight of this lectin was estimated to be 69,000 by gel filtration on Superdex-200. Electron microscopic observation of the purified lectin was reticular in structure and consisted of tandem aligned spherical basic units.


Effects Of Subchronic Treatment Of Some Plant Growth Regulators On Serum Enzyme Levels In Rats, İsmai̇l Çeli̇k, Hanefi̇ Özbek, Yasi̇n Tülüce Jan 2002

Effects Of Subchronic Treatment Of Some Plant Growth Regulators On Serum Enzyme Levels In Rats, İsmai̇l Çeli̇k, Hanefi̇ Özbek, Yasi̇n Tülüce

Turkish Journal of Biology

The effects of a sublethal concentration of three plant growth regulators (PRGs) on serum enzymes in rats were investigated under laboratory conditions. 100-ppm of PRGs, indoleacetic acid (IAA), indolebutiric acid (IBA) and kinetin were administered orally to 8 rats ad libitum for 3 weeks. The hormon treatments caused different effects on the level of serum alanin aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), amylase and creatine phosphokinase (CPK) in comparison to those of control rats. According to the results, while the levels of LDH and CPK were increased significantly by IBA, the levels of AST, LDH and CPK were …


The Chronic Effects Of Teucrium Polium On Some Blood Parameters And Histopathology Of Liver And Kidney In The Rat, Khaled Khleifat, Jumah Shakhanbeh, Khaled A. Tarawneh Jan 2002

The Chronic Effects Of Teucrium Polium On Some Blood Parameters And Histopathology Of Liver And Kidney In The Rat, Khaled Khleifat, Jumah Shakhanbeh, Khaled A. Tarawneh

Turkish Journal of Biology

The effects of chronic treatment with small sublethal doses (20 mg/kg and 50 mg/kg) of Teucrium polium ethanolic extract were investigated on the hematological and biochemical composition of the blood, histopathology of the liver and kidney, and fertility in the rat. Hematological and biochemical parameters of the blood, as well as sperm count, morphology and motility were normal after 6 weeks of herbal treatment. However, blood urea (P < 0.05) and cholesterol (P < 0.005) were significantly increased, with marked cytoplasmic vacuolation of the liver and kidney cells after chronic treatment with 50 mg/kg of the plant. These results demonstrate some histopathological effects of T. polium on the liver and kidney under long-term administration conditions.


A New Molecular Technique For The Identification Of Micro-Organisms In Biological Treatment Plants: Fluorescent In Situ Hybridization, Gülnur Coşkuner Jan 2002

A New Molecular Technique For The Identification Of Micro-Organisms In Biological Treatment Plants: Fluorescent In Situ Hybridization, Gülnur Coşkuner

Turkish Journal of Biology

Wastewater treatment has gained increased importance worldwide due to increasing demand on fresh clean water supplies. Biological treatment achieved by the activities of micro-organisms, is one of the most widely used processes in the treatment of wastewater. High numbers and activities of some groups of micro-organisms are required to treat wastewater in biological processes. In contrast, some groups of micro-organisms must be absent from the system since their presence and activities cause problems in the treatment of wastewater. The structure and function of micro-organisms in wastewater treatment plants (WWTP) have been investigated for decades. However, the identification of both the …


Effects Of Photoperiod And Temperature On Growth And Reproductive Organ Mass In Adult Male Mongolian Gerbils, Meriones Unguiculatus, Bülent Gündüz Jan 2002

Effects Of Photoperiod And Temperature On Growth And Reproductive Organ Mass In Adult Male Mongolian Gerbils, Meriones Unguiculatus, Bülent Gündüz

Turkish Journal of Biology

Rates of growth and sexual maturation of Mongolian gerbils vary in response to photoperiod. Previous work has shown that the responses of the testes and body weight of juvenile and adult gerbils are influenced not only by the photoperiods but also by other factors. The present work sought to determine if Mongolian gerbils alter body mass, body composition and/or reproductive organ mass in response to different photoperiods and temperatures. Male Mongolian gerbils were raised under long (14L) or short (10L) photoperiods from 26 days of age. Photoperiods did not affect body mass and body length. Temperature affected body mass only …


Food Intake And Feed Conversion Ratios In Abant Trout (Salmo Trutta Abanticus T., 1954) And Rainbow Trout (Oncorhynchus Mykiss W., 1792) In Pond Culture, İrfan Uysal, Ati̇lla Alpbaz Jan 2002

Food Intake And Feed Conversion Ratios In Abant Trout (Salmo Trutta Abanticus T., 1954) And Rainbow Trout (Oncorhynchus Mykiss W., 1792) In Pond Culture, İrfan Uysal, Ati̇lla Alpbaz

Turkish Journal of Biology

This study was carried out at DSI-Gölköy Fish Production Station in Bolu and lasted for 350 days. Food consumption (FC) and feed conversion ratios (FCR) in Abant and rainbow trout in pond culture were compared. Abant trout larvae obtained from eggs of wild Abant trout broodstocks in Lake Abant and rainbow trout larvae obtained from eggs of the cultured broodstocks in Gölköy Fish Production Station were used in this study. Trial I involved 4 groups (2 Abant and rainbow trout experimental groups and 2 Abant and rainbow trout parallel groups). Two hundred and thirty-six larvae were in each group; a …


Increasing The Injured Area On Hypocotyl Explants Of Flax (Linum Usitatissimum L.) Leads To High Frequency Callus-Based Shoot Regeneration, Mustafa Yildiz, Celal Er Jan 2002

Increasing The Injured Area On Hypocotyl Explants Of Flax (Linum Usitatissimum L.) Leads To High Frequency Callus-Based Shoot Regeneration, Mustafa Yildiz, Celal Er

Turkish Journal of Biology

In this study, it was aimed to increase the frequency of shoots, which would be nominated to be transgenic after Agrobacterium inoculation, through expanding the wounding area by peeling the epidermis layer of hypocotyl explants of flax plants. Callus weight, percentage of hypocotyls producing shoots, shoot number per explant and total shoot number per petri dish were recorded as 0.8 g, 40%, 4.24 and 16.96, respectively in non-peeled explants. On the other hand, when the epidermis layer was peeled, callus weight, percentage of hypocotyls producing shoots, shoot number per explant and total shoot number per petri dish increased to 1.35 …


Effect Of Some Biocides On Glutathione-S-Transferase In Barley, Wheat, Lentil And Chickpea Plants, Gülseren Coşkun, Fi̇gen Zi̇hni̇oğlu Jan 2002

Effect Of Some Biocides On Glutathione-S-Transferase In Barley, Wheat, Lentil And Chickpea Plants, Gülseren Coşkun, Fi̇gen Zi̇hni̇oğlu

Turkish Journal of Biology

The conjugation of glutathione with herbicides and insecticides is considered to be one of the major detoxification mechanisms of plants. This conjugation is catalysed by a family of multifunctional proteins known as glutathione-s-transferases. Treatment of wheat (Triticum aestivum L. cv. Cumhuriyet-75), barley (Hordeum vulgare L. cv. Kaya), chickpea (Cicer arietinum L. cv. Ispanyol), and lentil (Lens culinaris Medik. cv. Kışlık-kırmızı-51) with the selective herbicides 2,4-D (2,4-Dichloro phenoxyacetic acid) and linuron (N-(3,4-dichlorophenyl)-N´-methoxy-N´-methyl urea), and insecticides parathion methyl (O,O-dimethyl O-(4-nitrophenyl) phosphorothioate) and malathion (S-1,2-bis(ethoxycarbonyl)ethyl O,O-dimethyl phosphorodithioate) caused a progressive increase in glutathione-s-transferase activity in roots and shoots. The maximum increase in enzyme …


The Effects Of Heavy Metals On Pollen Germination And Pollen Tube Length In The Tobacco Plant, A. Levent Tuna, Betül Bürün, İbrahi̇m Yokaş, Esi̇n Çoban Jan 2002

The Effects Of Heavy Metals On Pollen Germination And Pollen Tube Length In The Tobacco Plant, A. Levent Tuna, Betül Bürün, İbrahi̇m Yokaş, Esi̇n Çoban

Turkish Journal of Biology

This study was carried out to determine the effects of heavy metals (Ni, Fe, Pb, Co, Cd, Hg, Al, Zn and Cu) on pollen germination and pollen tube length in the tobacco plant (Nicotiana tabacum L.) cv. Karabağlar. The results showed that enhanced concentrations of heavy metals, except Fe, decreased the pollen germination rates and the pollen tube lengths. With Fe concentrations, on the other hand, first a positive, and then a negative relation was determined between the pollen characteristics examined. The most toxic effect on pollen germination was seen with the applications of Cu, Ni and Hg; on pollen …


Use Of Ram Horn Hydrolysate As Peptone For Bacterial Growth, Esabi̇ Başaran Kurbanoğlu, Ömer Faruk Algur Jan 2002

Use Of Ram Horn Hydrolysate As Peptone For Bacterial Growth, Esabi̇ Başaran Kurbanoğlu, Ömer Faruk Algur

Turkish Journal of Biology

Peptone from ram horn was compared with a casein and other peptones for bacterial growth. First, horns were ground and 35 g of horn flour was hydrolyzed chemically (acid hydrolysis). As a result of this process, 30 g of the 35 g horn flour (85.7%) could be hydrolyzed. Hydrolyzed material was completed to 400 ml with deionized water, and this resulting solution was termed ram horn hydrolysate (RHH). The contents of protein, nitrogen, ash, some minerals, total sugars, total lipids and amino acids of RHH were determined. It was found that it has both organic and inorganic materials sufficient for …