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Serum Antiotensin Converting Enzyme Activity In Streptozotocin-Induced Diabetic Rats, Mustafa Vakur Bor, Esra Seval Elmali, Ni̇lgün Altan Jan 2000

Serum Antiotensin Converting Enzyme Activity In Streptozotocin-Induced Diabetic Rats, Mustafa Vakur Bor, Esra Seval Elmali, Ni̇lgün Altan

Turkish Journal of Medical Sciences

No abstract provided.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Medical Sciences

No abstract provided.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Dessiccation Using Saturated Salt Solutions And Improvement Germination Rate Of Walnut (Juglans Regia L.) Somatic Embryos, Hati̇ce Dumanoğlu Jan 2000

Dessiccation Using Saturated Salt Solutions And Improvement Germination Rate Of Walnut (Juglans Regia L.) Somatic Embryos, Hati̇ce Dumanoğlu

Turkish Journal of Agriculture and Forestry

Desiccation of somatic embryos under different air humidities conditioned by saturated salt solutions for different dura-tions; relationships between desiccation and germination or root formation in the dark; and effects of desiccation and gibberellic acid on germinating of 'Su-2' walnut somatic embryonic embryo line were investigated. Survival of embryos was low (about 10%) or zero when loss of fresh weight was about 90% and dry matter was about 70%. The highest germinating percentages (13.3-23.3%) were obtained with about 40.4-77.3% of loss of fresh weight and 9.1-34.6% of dry matter of desiccated embryos in covered plates over saturated MgCl 2 .6H 2 …


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Mathematics

No abstract provided.


Effects Of Different Media, Type And Concentrations Of Auxin On Callus Induction And Plant Regeneration From Young Inflorescences Of Yellow Bluestem (Bothriochloa Ischaemum(L.) Keng), Ersi̇n Can, Rüştü Hati̇poğlu Jan 2000

Effects Of Different Media, Type And Concentrations Of Auxin On Callus Induction And Plant Regeneration From Young Inflorescences Of Yellow Bluestem (Bothriochloa Ischaemum(L.) Keng), Ersi̇n Can, Rüştü Hati̇poğlu

Turkish Journal of Agriculture and Forestry

This study was conducted to determine the effects of different media, auxin types and concentrations on callus induction and plant regeneration from young inflorescences of 15 ecotypes of yellow bluestem ( Bothriochloa ischaemum). The young inflorescences were cultured on two different basal media (LS and SH) containing different concentrations (2, 4, 6, and 8 mg/l) of two different auxins (2, 4-D and Dicamba). The results showed that the ecotypes were significantly different from each other in callus induction rate, callus weight per dish and regenerate number per inflorescence segment. Depending on the ecotypes, mean callus induction rate varied from 9.7% …


A Quantitative And Qualitative Study On The Phytoplankton Of Palandöken Pond, Hasan Gürbüz, Zekeri̇ya Altuner Jan 2000

A Quantitative And Qualitative Study On The Phytoplankton Of Palandöken Pond, Hasan Gürbüz, Zekeri̇ya Altuner

Turkish Journal of Biology

In this research, the phytoplankton community of Palandöken pond was investigated quantitatively and qualitatively in samples taken vertically from the surface to 10 m depth between October 1990 and October 1992. The physical and chemical properties of the pond water were also determined. 99 taxa were determined in the phytoplankton and the proportions of them were as follows: Bacillariophyta 79%, Chlorophyta 10%, Cynophyta 6%, Euglenophyta 5%. The phytoplankton generally increased in the spring and early fall whereas in the summer and late fall it decreased. Physical factors had the greatest effect on phytoplankton growth.


The Effect Of Calcium Concentration Of Water Onchloride Cell Density In Gill Of Brown Trout(Salmo Trutta L.) Larvae, Meti̇n Çalta Jan 2000

The Effect Of Calcium Concentration Of Water Onchloride Cell Density In Gill Of Brown Trout(Salmo Trutta L.) Larvae, Meti̇n Çalta

Turkish Journal of Biology

The effects of the calcium concentration on chloride cell (mitochondria-rich cell) density in the gills of brown trout ( Salmo trutta L.) larvae were studied. For this purpose, animals were divided into 3 groups 2 weeks after hatching and each groups was exposed to different calcium concentrations of water for two weeks. The results showed that the number of chloride cells in gill arch epithelia of larval fish increased with decreased calcium concentration.This increase was statistically significant in the gills of larvae kept in zero-Ca 2+ freshwater (ZCWF) ( P< 0.001 ) and of those kept in low-Ca 2+ freshwater (LCFW) ( P< 0.05) in comparision with the gills of larvae kept in normal freshwater (NFW).


Study Of Adventitious Shoot Formation In Leaves Of Grape (Vitis Spp.), Ni̇lgün Göktürk Baydar Jan 2000

Study Of Adventitious Shoot Formation In Leaves Of Grape (Vitis Spp.), Ni̇lgün Göktürk Baydar

Turkish Journal of Biology

The effects of genotype, source of explant and nutrient medium on adventitious shoot formation were examined in the leaves of 5 grape cultivars (Atasarisi, Çavus, Kalecik Karasi, Sultani çekirdeksiz and Yapincak), 2 rootstocks (Kober 5BB ( V. berlandieri x V. riparia) and 41 B M.G. (Chasselas x V. berlandieri)) by organogenesis. In this study, petioles and laminae isolated from in vitro shoots were used as the sources of explant. The highest rates of adventitious shoot formation were obtained from petiole explants. Leaf explants were cultured on MS- and NN- based regeneration media containing different concentrations of BAP and NAA. It …


Agronomic And Technological Properties Of Coriander ( Coriandrum Sativum L.) Populations Planted On Different Dates, Nermi̇n Kaya, Güngör Yilmaz, İsa Telci̇ Jan 2000

Agronomic And Technological Properties Of Coriander ( Coriandrum Sativum L.) Populations Planted On Different Dates, Nermi̇n Kaya, Güngör Yilmaz, İsa Telci̇

Turkish Journal of Agriculture and Forestry

This research was conducted to determine suitable sowing dates and the potential productivity of coriander (Coriandrum sativumL.), grown in the Mardin, Denizli and Erzurum districts, at Tokat ecological conditions in 1997 and 1998 vegetation periods. Three local populations from Mardin, Denizli and Erzurum were sown on four different dates (1 November, 1 March, 15 March and 1 April). The highest seed yield was obtained from the Erzurum population as 908 kg/ha. The greatest essential oil ratio was recorded from the Denizli population with 0.39%. Linalool which is main component of coriander essential oil varied from 50.52- 92.52. Plant height (48.6-73.2 …


Effects Of Some Plant Residues On Nitrogen Mineralization And Biological Activity In Soils, Emi̇ne Erman Kara Jan 2000

Effects Of Some Plant Residues On Nitrogen Mineralization And Biological Activity In Soils, Emi̇ne Erman Kara

Turkish Journal of Agriculture and Forestry

The objective of this experiment was to determine the rate of decomposition and nitrogen mineralization of plant residues in soil under laboratory conditions. The experiment consisted of six treatments: control, industrial tobacco residues, rice straw, rice straw + mineral nitrogen, rice husks and rice husks+mineral nitrogen. The plant materials were added at a rate of 2000 mg/kgC and the amount of NH 4 + -N completed the C:N ratio of the added materials to 12.5. After adding the plant material the following measurements were carried out: soil respiration measurements 14 times, dehydrogenase activity 14 times, mineral nitrogen (ammonium and nitrate). …


Relationship Between Leaf Area Index At Anthesis And Yield In Wheat Under Çukurova Conditions, Müjde Koç, Celaleddi̇n Barutçular Jan 2000

Relationship Between Leaf Area Index At Anthesis And Yield In Wheat Under Çukurova Conditions, Müjde Koç, Celaleddi̇n Barutçular

Turkish Journal of Agriculture and Forestry

Wheat yields are closely related to leaf area index (LAI) at anthesis. The optimum leaf area index differs according to genotype and location conditions. Three field experiments were conducted to determine the pattern of the relationship between LAI at anthesis and yield in Çukurova , a region with an acclerated ear and grain growth. Different genotypes, seeding density and nitrogen doses were used to create a range of LAI. Biological yield (BY) and grain yield (GY) increased quadratically in response to LAI values, with greater responses for BY (R 2 =0.46**) than for GY (R 2 =0.35**). As LAI increased …


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


A Local Zero-Two Law And Some Applications, Radu Zaharopol Jan 2000

A Local Zero-Two Law And Some Applications, Radu Zaharopol

Turkish Journal of Mathematics

In the paper we obtain a local zero-two law for positive contractions of $L^1$-spaces, which we use in order to offer new proofs of a theorem of Orey concerning Markov chains, and of the strong asymptotic stability of certain Markov operators that have appeared in the study of the Tjon-Wu equation and in connection with the Hannsgen and Tyson model of the cell cycle.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Mathematics

No abstract provided.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Mathematics

No abstract provided.


Stereoselective Synthesis Of Butenolide And Butyrolactone Derivatives, Abdulkadi̇r Sirit Jan 2000

Stereoselective Synthesis Of Butenolide And Butyrolactone Derivatives, Abdulkadi̇r Sirit

Turkish Journal of Chemistry

Optically active butenolide and $\gamma$-butyrolactone derivatives were prepared by removing (R)-phenyl glycinol and (1R, 2R)-norpseudoephedrine used as chiral auxiliaries from butenolides and \gamma-butyrolactones in two steps. The structures of these products were determined using ^1H NMR, ^{13}C NMR, Mass spect., IR and microanalysis.


The Cytogenetic Effects Of Npyr On Mice, Mehmet Korkmaz, Ahmet Çolak Jan 2000

The Cytogenetic Effects Of Npyr On Mice, Mehmet Korkmaz, Ahmet Çolak

Turkish Journal of Biology

The effects of N-nitrosopyrrolidine (NPYR) on mice chromosomes and micronucleus induction were investigated in order to evaluate its genotoxic effects. Twenty 10-12 week old mice and 40 8- 10 week old male mice ( Mus musculus var. albinos) were used for chromosome analysis without sex discrimination and micronucleus tests respectively. Mice were intraperitoneally treated in single injections with three dose levels (100, 200 and 300 mg/kg) of NPYR with isotonic saline as the solvent vehicle. Bone marrow was sampled at 24 and 48 h postinjection. Examination of the mice bone marrow chromosomes at the metaphase (24 h) showed that in …


A Quantitative And Qualitative Study On The Benthic Algal Floraof Palandöken Pond, Hasan Gürbüz Jan 2000

A Quantitative And Qualitative Study On The Benthic Algal Floraof Palandöken Pond, Hasan Gürbüz

Turkish Journal of Biology

In this study, the composition and density of the benthic algae and seasonal variations of the benthic algae of Palandöken Pond were determined between September 1990 and September 1992. Samples were collected from two previously selected sampling sites. It was found that Bacillariophyta was the dominant benthic algal group in this pond. During our investigation a total of 160 taxa were identified and 135 them were composed of epipelic algae. The percentages of algal groups were as follows: Bacillariophyta 57%, Cholorphyta 11% and Euglenophyta5%. It was found that there were plenty of epipelic algal species living together with epiphytic and …


The Monthly Variations Of Blood Glucose Level Of Capoeta Tinca Capoeta(Heckel, 1843) In Çoruh Basin-Oltu Stream, Ayhan Yildirim, Mustafa Türkmen, İrfan Altuntaş Jan 2000

The Monthly Variations Of Blood Glucose Level Of Capoeta Tinca Capoeta(Heckel, 1843) In Çoruh Basin-Oltu Stream, Ayhan Yildirim, Mustafa Türkmen, İrfan Altuntaş

Turkish Journal of Biology

In this study, the monthly variation of blood glucose level of Capoeta tinca caught from in Çoruh Basin - Oltu Stream, between Augist 1995 and June 1996 was determined. It was determined that the average blood glucose level was 86.19±3.86 mg/dl in males and 83.58±3.77 mg/dl in females. The blood glucose level was highest (116.36±8.58 mg/dl) in April, and lowest (51.00±7.10 mg/dl) in June.


Detection Of Mutagenic Effects Of 2, 4, 5 Tri (Sübstitüe) Phenyl Imidazole And Its Derivatives In Ames/Salmonella/Test System, Ayşe Mercangöz, Berri̇n Ayaz Tüylü Jan 2000

Detection Of Mutagenic Effects Of 2, 4, 5 Tri (Sübstitüe) Phenyl Imidazole And Its Derivatives In Ames/Salmonella/Test System, Ayşe Mercangöz, Berri̇n Ayaz Tüylü

Turkish Journal of Biology

The mutagenic effects of 2, 4, 5 tri-phenylimidazole and its nine different derivatives, which are aimed at producing medicine as a primary substance, were investigated by the Ames Salmonella/Microsome plate assay. The test compounds were directly effective, especially in the TA 98 strain. A relationship was found between the mutagenic effect and the positions of the methyl and methoxy groups.


The Inhibition Effect Of Yoghurt Starter Culture Metabolites, Belma Aslim, Yavuz Beyatli, Kadi̇r Halkman Jan 2000

The Inhibition Effect Of Yoghurt Starter Culture Metabolites, Belma Aslim, Yavuz Beyatli, Kadi̇r Halkman

Turkish Journal of Biology

In this study effect of some separate and combined metabolic compounds produced by lactic acid were tested on food pathogenic and contaminant microorgnasms. For this study, five strains of each Lactobacillus bulgaricus and Streptococcus thermophilus were used. The inhibition effects of the metabolic products (lactic acid, hydrogen peroxide, acetaldehyde, diacetyl) produced by the stains on test bacteria ( Staphylococcus aureus, Escherichia coli) were determined. Also, a random combinations of the strains were prepared and the metabolic compounds produced by these cultures and their antimicrobial activities on tested bacteria were determined. By regarding the metabolic products mainly, the samples of lactic …


Investigation Of Selected Industrially Important Enzymatic Activities Of Turkish Agricultural Mycoflora-I: Amylase, Lipase, Protease, Şemi̇nur Topal, Ceyda Pembeci̇, Mehli̇ka Borcakli, Mehmet Batum, Özlem Çelti̇k Jan 2000

Investigation Of Selected Industrially Important Enzymatic Activities Of Turkish Agricultural Mycoflora-I: Amylase, Lipase, Protease, Şemi̇nur Topal, Ceyda Pembeci̇, Mehli̇ka Borcakli, Mehmet Batum, Özlem Çelti̇k

Turkish Journal of Biology

In this context, fungi being a rich source in from metabolites point of view, their utilization possibilities in various area are investigated. Primary metabolites of the fungi representing Turkish agricultural mycoflora which belongs to our culture collections are determined and their importance with respect to industry will be evaluated. It is assumed that enzymes such as, protease, amylase, lipase, cellulase, xylanase, b-glucanase, pectinase of these moulds represent a potential source for food industry. In this context, qualitative screening three of these enzymes producing abilities of relevant moulds are carried out. Methods used for enzyme determination cover, "Opacity Capacities in Deep …


The Population Structure And Growth Properties Of Chalcalburnusmossulensis (Heckel, 1843) Caught From Askale Region Of River Karasu, Mustafa Türkmen, İhsan Akyurt Jan 2000

The Population Structure And Growth Properties Of Chalcalburnusmossulensis (Heckel, 1843) Caught From Askale Region Of River Karasu, Mustafa Türkmen, İhsan Akyurt

Turkish Journal of Biology

In this study, the population structure and growth properties of Chalcalburnus mossulensis (Heckel, 1843) caught from Askale Region of River Karasu betwen February 1996 and January 1997 were examined. The age composition of population varied between I and VI ages, and the most abundant age group was the third age group (42.13%). The population was composed of 51.74% females and 48.26% males. The fork length and the body weights of males and females varied between 8.9-18.1 cm, 3.6-67.9 g and 8.5-18.5 cm, 5.1-79.5 g respectively. The specific and relative growth for length and weight were maximum in the second age. …


The Effects Of Malt Extract And Corn Strach On The Vegetativedevelopment And Morphology Of The Pleurotus Floridafovose Mycelia, Abdunnasir Yildiz Jan 2000

The Effects Of Malt Extract And Corn Strach On The Vegetativedevelopment And Morphology Of The Pleurotus Floridafovose Mycelia, Abdunnasir Yildiz

Turkish Journal of Biology

No statistical differences were determined in the effects of malt extract (ME) and corn strach (CS) doses on the vegetative development of mycelia (P>0.05). The mycelia in all gropus covered 9.0 cm agar plates in 9.0 days and some characteristic differences, development from (vertical or horizontal), cluster formation, tickening and tissue formations, were observed. In the group containing 2% CS, the mycelia formed a sparse development horizontally on the surface and center of the agar plate, whereas clustering, thickening and tissue formation wereobserved in the form of a thick zone on the edges of the petri dishes. In 1.5% …


Changes In Liver Cytoplasmic Glutathione-S-Transferase And Microsomalnitrosodimethylamine Demethylase Activities In Chicks Obtainedfollowing Daminozide Treatment, Yavuz Si̇li̇ğ, V. Kenan Çeli̇k, Ati̇lla Atalay Jan 2000

Changes In Liver Cytoplasmic Glutathione-S-Transferase And Microsomalnitrosodimethylamine Demethylase Activities In Chicks Obtainedfollowing Daminozide Treatment, Yavuz Si̇li̇ğ, V. Kenan Çeli̇k, Ati̇lla Atalay

Turkish Journal of Biology

In this study, microsomal nitrosodimethylamine demethylase (NDMAd) and cytoplasmic glutathione-s-tarnsferase (GST) activities in the livers of chicks obtained from the LD 10 (3 mg/ml) and LD 30 (9 mg/ml) doses of daminozide (Succinic acid 2,2-Dimethylhydrazide) injected Ross-Pm-3 fertilized chicken eggs were investigated. Spectrophotometric determination of NDMAd activity was performed at 412 nm by the detection of yellow coloured compound formed as a product of the reaction of formaldehyde with Nash reagent. No significant increase was observed in NDMAd activity (P>0.05) of the group treated with LD 10 dose although NDMAd activity was found to be significantly increased (P


The Effect Of Olive Oil Mill Effluent On The Mitotic Cell Division And Total Protein Amount Of The Root Tips Of Triticum Aestivuml., Mehmet Aybeke, Göksel Olgun, Uğur Sidal, Dürdane Kolankaya Jan 2000

The Effect Of Olive Oil Mill Effluent On The Mitotic Cell Division And Total Protein Amount Of The Root Tips Of Triticum Aestivuml., Mehmet Aybeke, Göksel Olgun, Uğur Sidal, Dürdane Kolankaya

Turkish Journal of Biology

In this work sitotoxic and mutagenic effects Olive Oil Mill Effluent (OOME) on the root tips of Triticum aestivumL. were investigated. In this purpose, germination rate of seeds, mitotic division abnormalities and total protein amounts were evaluated. The seeds kept in various OOME concentrastions, it was determinated that germination rate decreased, whilst mitotic abnormalities and mitotic cell division frequency increased. Especially, the increased cell division frequency was of significance, almost several times higher than the control group. The cells having multinucleus or fragmented nucleus and numerical or sutructural mutations were also found. Furthermore it was observed that total protein amounts …