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101.
The study aimed to determine the reproductive characteristics of the broad‐snout Chondrostoma holmwoodii population (spawning season, number of eggs and first age of sexual maturity) in order to assess the population status in the Tahtal? Dam Lake reservoir. A total of 1208 specimens were examined of which 72.1% were females and 27.9% males (female:male ratio = 1 : 0.40); the percentage of males, however, declined in the higher age classes (IV and V). The monthly determined gonadosomatic index indicated that the peak reproduction period of the species is in April and early May. The study covered age classes I–V, with specimens at age II reaching maturity. The total number of eggs per female varied from 8000 to 41 700, the mean number of eggs increasing proportionally with age of the spawner. Egg diameters also increased during the 5‐month ripening period from December to April.  相似文献   
102.
Carbonic anhydrase (CA; EC 4.2.1.1) was purified from the gill of the teleost fish Dicentrarchus labrax (European seabass). The purification procedure consisted of a single step affinity chromatography on Sepharose 4B-tyrosine-sulfanilamide. The enzyme was purified 84.9-fold with a yield of 58%, and a specific activity of 838.9 U/mg proteins. It has an optimum pH at 8.0; an optimum temperature at 10°C. The kinetic parameters of this enzyme were determined for its esterase activity, with 4-nitrophenyl acetate (NPA) as substrate. The following anions, H?NSO??, I?, SCN?, NO??, NO??, N??, Br?, Cl?, SO?2?, and F? showed inhibitory effects on the enzyme. Sulfamic acid, iodide, and thiocyanate exhibited the strongest inhibitory action, in the micromolar range (K(i)s of 87-187 μM). NO??, NO?? and N?? were moderate inhibitors, whereas other anions showed only weak actions. All tested anions inhibited the enzyme in a competitive manner. Our findings indicate that these anions inhibit the fish enzyme in a similar manner to other α-CAs from mammals investigated earlier, but the susceptibility to various anions differs significantly between the fish and mammalian CAs.  相似文献   
103.
Venlafaxine is an approved antidepressant that is an inhibitor of both serotonin and norepinephrine transporters. Medical treatment with oral venlafaxine can be beneficial to depression due to reducing free radical production in the brain and medulla of depression- induced rats because oxidative stress may a play role in some depression. We investigated the effect of venlafaxine administration and experimental depression on lipid peroxidation and antioxidant levels in cortex brain, medulla and erythrocytes of rats. Thirty male wistar rats were used and were randomly divided into three groups. Venlafaxine (20 mg/kg) was orally supplemented to depression-induced rats constituting the first group for four week. Second group was depression-induced group although third group was used as control. Depressions in the first and second groups were induced on day zero of the study by chronic mild stress. Brain, medulla and erythrocytes samples were taken from all animals on day 28. Depression resulted in significant decrease in the glutathione peroxidase (GSH-Px) activity and vitamin C concentrations of cortex brain, glutathione (GSH) value of medulla although their levels were increased by venlafaxine administration to the animals of depression group. The lipid peroxidation levels in the three tissues and nitric oxide value in cortex brain elevated although their levels were decreased by venlafaxine administration. There were no significant changes in cortex brain vitamin A, erythrocytes vitamin C, GSH-Px and GSH, medulla vitamin A, GSH and GSH-Px values. In conclusion, cortex brain within the three tissues was most affected by oxidative stress although there was the beneficial effect of venlafaxine in the brain of depression-induced rats on investigated antioxidant defenses in the rat model. The treatment of depression by venlafaxine may also play a role in preventing oxidative stress. Abstract of the paper was submitted in 1st Ion Channels and Oxidative Stress Congress, 14–16 September 2006, Isparta, Turkey.  相似文献   
104.
Journal of Plant Biochemistry and Biotechnology - Wheat is the second important cereal crop worldwide due to nutritional composition and role in meeting daily energy needs. Salinity is an abiotic...  相似文献   
105.
In Vitro Cellular & Developmental Biology - Plant - Gentiana species belonging to the Gentianaceae family are medicinal plants rich in glycosides and phenolics. Gentiana lutea L. is a highly...  相似文献   
106.
Reactive oxygen species can bind protein, DNA, lipids, and carbohydrates and thus cause an oxidation reaction that induces various syndromes such as cardiovascular diseases, degenerative disease, and cancer types in the human body. Bioactive compounds, such as PUFA, EPA, DHA, and carotenoids in algae, have a chain ring and protect the tissue from chemical damage and reverse the symptoms of some diseases. Algal bioactives also have various biological properties such as anticoagulants, antiviral, antiangiogenic, antitumor, anti-inflammatory, antioxidant, antiproliferative, and immune modulation properties. This study aimed to show in vitro cytotoxic activity effect of Chlorella protothecoides and Nannochloropsis oculata microalgal extracts loaded nano–microparticles on A-172 (Homo sapiens brain glioblastoma) and HCT-116 (H. sapiens colon colorectal carcinoma) cell lines because of the increasing importance of algal biotechnology. MTT viability tests were performed on HUVEC, A172, and HCT 116 cells with particles obtained at optimum process parameters. The cell viability rates of encapsulated particles were also compared with pure algae extracts. Microalgal extracts loaded nano–micro particles showed very promising results for cytotoxic effect on cancer cells.  相似文献   
107.
Amsonia orientalis Decne. (Apocynaceae), is a rare and threatened plant species which is located only in a constricted area in northeast of Greece and northwest of Turkey in the world. Although phylogenetic analysis depending on nucleotide sequences of genes from different sources (nucleus, mitochondria and chloroplast) became a major tool for classification of plant species, there is still a big lack of information about A. orientalis in the international molecular data bases such as NCBI. In the current study, we phylogenetically analyzed three commonly used molecular markers (18S rDNA, 18S-28S rDNA-ITS region and trnL-F intergenic spacer) from A. orientalis samples collected from Turkey to determine the genetic diversity and also to question the systematic position of A. orientalis. As a result, A. orientalis samples clearly showed close relation with Alyxieae tribe rather than Vinceae. And this result brings the necessity to reconsider the morphological characters that have used to delimit the tribes of Rauvolfioideae.  相似文献   
108.

Aim

The objective of this study was to examine whether MT plays a protective role against the damage in the liver by administering carbontetrachloride (CCl4) to rats.

Main method

28 male Wistar albino (n = 28, 8 weeks old) rats have been used in the study. The rats were distributed into 4 groups according to their live weights. The groups were: (i) negative control (NC): normal water consuming group to which no CCl4 and milk thistle (MT) is administered; (ii) positive control (PC): normal water consuming group to which no CCl4 is administered but MT is administered; (iii) CCl4 group: normal water consuming and group to which CCl4 is administered (2 ml/kg live weight, ip); and (iv) CCl4 + MT group: CCl4 and MT administered group (2 ml/kg live weight, ip). Caspase-3, caspase-9, bax, and bcl-2 protein syntheses were examined via western blotting. MDA determination in liver tissue was made using spectrophotometer.

Key findings

MDA amount has decreased in the CCl4 + MT group in comparison to CCl4 group whereas caspase-3 and caspase-9 has increased and bax and bcl-2 has decreased.

Significance

These results show that MT protects the liver against oxidative damage.  相似文献   
109.
Genetic stability of plants during in vitro propagation and conservation is one of the important aspects of plant biotechnology. In the present study, micropropagated P. lentiscus L. shoot cultures, which are cultivated for the mastic resin, have been cold stored up to 12 months at 4 °C in the dark for different durations (2, 4, 6, 8, 10 and 12 months) and genetic alterations in cold storage conditions were evaluated. Growth parameters such as proliferation rate, shoot numbers per explant, shoot lengths and shoot forming capacity were also calculated. Since the highest proliferation rate (100 %) was obtained in 6?month-stored shoot cultures without any severe influence of cold stress on proliferation ability, amplified fragment length polymorphism (AFLP) and inter-retrotransposon amplified polymorphism (IRAP) marker systems were used to determine genetic stability in the plantlets after this storage period. Totally, 702 scorable bands were produced by 10 AFLP primer pairs. Genetic similarity value of the non-stored (control) plant and cold-stored clones ranged from 0.66 to 0.84 with a mean of 0.74. In the case of IRAP, 159 bands were produced by 8 IRAP primers. Genetic similarity value of the non-stored plant and cold-stored clones varied from 0.65 to 0.83 and the average genetic similarity value was determined as 0.72. The genetic similarity indices revealed that genetic variability was similar in both techniques. Our results showed that tissue culture and especially cold storage of P. lentiscus L. may result transposons activation, thus could cause genetic instability.  相似文献   
110.
This study aims to research the effect of streptozotocin (STZ) at different doses on the serum micronutrients and oxidative stress status in diabetic rat models. Twenty male rats averaged 250 g and 3–4 months old were used as experimental models. They were put in four groups composed of five rats each. Diabetic was induced by administering STZ 55 and 65 mg/kg intraperitonally. The serum micronutrients including minerals and vitamins (Cu, Zn, Mg, Fe, vitamins D, E, and C) and oxidative stress (malondialdehyde, MDA) were determined. Cu, Zn, and Vitamin D3 levels were found to increase significantly in STZ groups (p < 0.005). Retinol levels decreased significantly in STZ groups (p < 0.005). In the groups administered 55 mg/kg STZ ferrum and vitamin C levels were found significantly lower than the other groups (p < 0.005). In the group given 65 mg/kg STZ α-tocopherol levels were highest (p < 0.005) among other groups. There was not any difference between the groups for MDA, Cu/Zn, and Mg. For both doses, oxidative stress status was not significantly affected within 48 h of the application, however, some micronutritents were affected significantly.  相似文献   
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