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1.
The objectives of this study were to examine the free radical scavenging activity and the protective effects against macromolecular oxidation as well as the cytotoxic activity of Aphanes arvensis aqueous and methanolic extracts. Free radical scavenging activity was determined by DPPH method. The methanolic extract showed a scavenging activity nearly equivalent to Trolox and Vitamin C and has an IC50 value of 4.54 μg/mL. Total antioxidant capacity was determined by CUPRAC method. The antioxidant capacity of aqueous and methanolic extract was 0.792 and 1.550 mmol TE/g DWE, respectively. The protective effect of A. arvensis extracts against lipid peroxidation was evaluated using a liposome oxidation system. The methanolic extract was more active than the aqueous extract. The aqueous extract possessed protective effect against protein oxidation in a dose dependent manner. Both extracts showed inhibitory effect on DNA oxidation as measured by plasmid relaxation assay. Results presented here indicate that A. arvensis possess strong antioxidant activity and protective effects with very little cytotoxic effect, and they can therefore be used as a natural additive in food, cosmetic and pharmaceutical industries.  相似文献   
2.
The aim of this study was to evaluate the effects of Roswell Park Memorial Institute (RPMI) 1,640 medium on chilled storage of eggs and spermatozoa of rainbow trout (Oncorhynchus mykiss). After 3 days of storage, eggs in RPMI 1,640 media (pH 8.2, 9 and 10), Cortland medium and coelomic fluid were inseminated with fresh spermatozoa (Experiment 1). Eggs in RPMI 1,640 medium at pH 8.2 shown the lowest thiobarbituric acid‐reactive substances (TBARS, 0.053 ± 0.003 nmol/ml) and pH changes (from 8.20 ± 0.01 to 8.18 ± 0.01), the highest fertilization rate (82 ± 3%). Undiluted and diluted spermatozoa at ratios of 1:2 and 1:9 with RPMI 1,640 media (pH 8.2, 9 and 10) and Cortland medium were inseminated with fresh eggs (Experiment 2). Spermatozoa in RPMI 1,640 medium at pH 9 (1:9) caused the lowest TBARS content (0.037 ± 0.002 nmol/ml) and pH changes (from 9.00 ± 0.01 to 8.98 ± 0.01), the highest fertilization rate (77 ± 2%) and motility parameters. Based on Experiments 1 and 2, eggs and spermatozoa were stored for another 3 days in RPMI 1,640 medium at pH 8.2 and 9 (1:9) respectively (Experiment 3). Fertilization rate of storage eggs and spermatozoa in Experiment 3 was 79 ± 5%, showing successfully storage of rainbow trout gametes with the same medium.  相似文献   
3.
The effects of environmental enrichment and transport stress on the immune system were investigated in laying hens. A total of 48 1‐day‐old chickens were used, half of the chickens were reared in conventional cages (RCC) and the rest in enriched cages (REC). Transport stress was applied in the 17th week. Liver weight decreased, spleen and bursa of Fabricius weights, white blood cell count, CD4+ and CD8+ cell proportions increased due to the transport. Environmental enrichment significantly increased antibody production and tended to increase monocyte percentage and CD8+ cell proportion. The effect of transport on, heterophil (H) and lymphocyte (L) percentages was not significant in RCC chickens. While heterophil percentage and H:L ratio increased, lymphocyte percentage decreased in REC chickens subjected to transport. Transport stress increased heterophil functions both in REC and RCC chickens, but the increase was higher in REC hens than in RCC hens. In conclusion, although environmental enrichment did not neutralize the effect of transport on lymphoid organs, it activated the non‐specific immune system, cellular and the humoral branches of the specific immune system by increasing heterophil functions, CD8+ cells and antibody production, respectively. Therefore, environmental enrichment suggested for improving animal welfare may also be beneficial to improve the immune system of birds exposed to stress.  相似文献   
4.
Onay-Uçar E  Karagöz A  Arda N 《Fitoterapia》2006,77(7-8):556-560
Methanolic extracts of Viscum album ssp. album (mistletoe) grown on different host trees were investigated for their potential antioxidant activity. Scavenging activity was tested by 1,1­diphenyl­2­picrylhydrazyl (DPPH) method and the inhibitory effect on lipid peroxidation was examined by ferric thiocyanate and thiobarbituric acid methods. The extract from mistletoe grown on lime tree in summer showed the highest activity. It was found that antioxidant capacity of the plant differed according to the harvesting time as well as the host tree.  相似文献   
5.
Buyukcekmece Reservoir, located in the western outskirts of Istanbul, is one of the major water resources of Istanbul, and supplies drinking water to about 4 million people. Erosion in the catchment of the reservoir is an important problem in terms of its longer-term sustainability for water supply. There is an urgent need to obtain reliable quantitative data regarding erosion and deposition rates within the catchment to assess the magnitude of the problem and to plan catchment management strategies. In the absence of existing data, attention has focussed on the potential for using 137Cs measurements to provide retrospective estimates of medium-term soil erosion rates within the catchment over the past ca. 40 years. To date, the 137Cs approach has not been used to document soil redistribution rates in Turkey and this contribution reports an attempt to confirm the viability of the approach and the results of a preliminary investigation of rates of soil loss from uncultivated areas within the catchment. The soil redistribution rates estimated using the profile distribution conversion model varied from − 16.11 (erosion) to 4.59 (deposition) t/ha/year.  相似文献   
6.
In the present study, 12 microsatellite loci (ETH10, ETH225, ETH03, TGLA122, TGLA227, BM1824, BM2113, INRA23, SPS115, TGLA126, RM006 and BM1818) were evaluated for their possible use to confirm selected pedigree relationships between 7 bulls, their 21 male offspring, and their 64 second-generation female offspring within the progeny test started in Turkey. The nine loci (BM1824, INRA23, BM2113, SPS115, ETH10, TGLA122, ETH225, TGLA126 and TGLA227) recommended by ISAG displayed high values for the measures of informativeness (allele numbers, heterozygosity, polymorphic information content, frequency of the most common allele, and power of discrimination). When both parents are known calculated combined probability of exclusion was at least 0.999. Range of probability of paternity (POP) values were 0.814–0.9999. Except 3 cases (4.7%), the alleged paternity relationships were confirmed. To have a higher confidence in POP values new loci must be integrated into the set of 9 loci used.  相似文献   
7.
We evaluated fungal decay and mold resistance, leaching, and water absorption of nano-compounds and Paraloid B72® (PB72) in treated wood specimens to develop new methods of consolidation by combining nano-particles and consolidants. Scots pine wood specimens were treated with dispersions of nano-CuO, nano-ZnO, nano-B2O3, nano-TiO2, and nano-CeO2. PB72 treatments of nano-particle-treated wood specimens were then carried out by either vacuum or immersion for 24 h. Previously, decayed wood specimens were also consolidated with the nano-compounds and PB72. PB72 treatments reduced element release from treated wood specimens. Nearly all nano-compounds + PB72 treatments increased the biological performance of treated wood specimens against decay fungi tested. PB72-only treated wood specimens had the highest weight losses in decay tests. No improvements were obtained in mold resistance tests when the nano-compounds and PB72 were combined. In nano-compound-only treatments, unleached specimens showed slightly lower water absorption values compared to untreated control specimens. Incorporation of PB72 into nano-compound-treated wood specimens resulted in considerably lower water absorption and volumetric swell. In previously decayed specimens treated with the nano-compounds and PB72 solution, water absorption after 2-h immersion declined compared to control specimens.  相似文献   
8.
The effects of body and meals sizes on gastric evacuation (GE) of the endangered Siberian sturgeon (Acipenser baerii) were parameterized (at temperatures ranging from 16.8 to 17.6°C) using radiography technique. GE experiments were performed using different body sizes A. baerii ranged from 1.5 kg to 5 kg fed on meal sizes of 4.6 g to 47.6 g composed of either commercial pellets or live food (fish prey, whiting). The commercial pellets used in these experiments had barium sulphate at concentrations of 20%, while the same amount was injected into the body of live food for radiography technique monitoring. The course of GE in A. baerii was best described by the square root model independently of meal size. The effects of body mass and temperature on GE rates were described by power model and simple exponential model respectively. GE rates of A. baerii fed on live food could be summarized by (g/hr), while for commercial pellets, where St is the stomach contents mass (g), W is fish wet weight (cm), T is temperature (°C), and t is time (hr). These summarized models could estimate the time required for a meal to be evacuated from the stomach of A. baerii or determine the stomach fullness at postprandial time t. These results will assess the planning of feeding regime for A. baerii to avoid their overfeeding and underfeeding.  相似文献   
9.
Azithromycin, an azalide subclass macrolide antibiotic, is an effective, well-tolerated and safe therapeutic option for treatment of papillomatosis in humans. This study reports the clinical and histopathological results from a prospective, randomized, double-blinded, placebo-controlled trial of 17 dogs of various breeds with diagnosis of oral ( n = 12) and cutaneous papillomatosis ( n = 5) treated with azithromycin. Papillomas appeared as whitish, verrucous, hyperkeratotic papules 1–2.7 mm in size. The cases were randomly assigned to azithromycin ( n = 10) and placebo treatment groups ( n = 7). Both owners and investigators were blinded to the allocation to the groups. Azithromycin (10 mg/kg) was administered per os every 24 h for 10 days. Clinical evaluations were done by the same investigator throughout the trial. Azithromycin treatment significantly decreased clinical scores ( P  < 0.001), whereas there was no change seen in the placebo group. In the azithromycin treatment group, skin lesions disappeared in 10–15 days. One case in the placebo had spontaneous regression of its papillomas by day 41, but lesions were still evident at day 50 in the remaining six cases. There was no recurrence of papillomatosis in the azithromycin treated dogs (follow up 8 months). No adverse effects were seen in either group. In conclusion, azithromycin appears to be a safe and effective treatment for canine papillomatosis.  相似文献   
10.
Selenium (Se), regarded as an antioxidant, has been found beneficial for plants growing under stressed conditions. To investigate whether the Se application helps to improve stress tolerance, sodium selenite (Na2SeO3 · 5H2O, 5–15 μM) was hydroponically applied to Zea mays variety OSSK-713-roots under heat and/or PEG-induced osmotic stress (25% PEG-6000) for 8 h. The individual/combined stress caused accumulation of reactive oxygen species (ROS). While only superoxide dismutase (SOD) increased with heat stress alone, the activities of SOD, catalase (CAT) and ascorbate peroxidase (APX) increased under PEG exposure. The combination of these stresses resulted in an induction of both SOD and CAT activities. Lipid peroxidation (TBARS) levels were also high in all the stress treatments, especially under the combination treatment. Addition of Se not only improved the activities of SOD, APX and glutathione reductase (GR) in stress-treated roots, but it also changed the activities of monodehydroascorbate reductase (MDHAR) and dehydroascorbate reductase (DHAR). The findings reveal that Se has a positive effect on heat and/or osmotic stress mitigation mainly by regulating the ascorbate-glutathione cycle, especially in PEG-treated plants. Under the combined stress treatment, addition of 5 µM of exogenous Se was most effective.  相似文献   
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