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51.
Persian Gulf cuttlefish mantles were hydrolyzed (CPH) using alcalase, and the optimal hydrolysis parameters were obtained for the highest degree of hydrolysis (DH) and strongest antioxidant (based on their ability to quench 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals) activity using response surface methodology (RSM). The predicted optimal parameters of DH and quenching DPPH radicals was: pH of 7.88, 50.2°C, 150 min, and enzyme to substrate ratio of 1.5%. The reducing power (RP) and ability of optimized peptides to quench ABTS radicals in a gastro-intestinal track model system increased during the intestinal stage, while scavenging ability against DPPH radicals dropped (P < 0.05). The oxidation of lipid was retarded in a lecithin-liposome model added with optimized CPH in a concentration dependent response. Ultrafiltration of optimized CPH showed that the 3–10 KDa fraction had the greatest DPPH radical scavenging activity, the 10–30 KDa fraction had the highest reducing power, and the <3 KDa fraction had the greatest ABTS radical scavenging activity.  相似文献   
52.
This study aimed to evaluate the antilisterial and antioxidative effects of chitosan nanocomposites and rosemary extract coating on the fillet of Huso huso inoculated with Listeria monocytogenes during refrigerated storage (4°C). Fish fillets were subjected as control (without coating), 0.5% rosemary extract (RE), 1% chitosan (CS), and combination of chitosan and rosemary extract as chitosan nanocomposite (CS/RE). Then, samples were inoculated with L. monocytogenes. Subsequently, the chemical parameters (total volatile basic nitrogen (TVB-N), peroxide value (PV), pH, and thiobarbituric acid (TBA)) and antilisterial effects of coatings were monitored during 16 days of storage at 4°C. According to the results, CS/RE demonstrated a significant (p < 0.05) ability to inhibit the growth of L. monocytogenes from 4.14 log cfu/g to 2.23 log cfu/g at the end of the storage period, followed by CT and RET treatments, respectively, compared to the control. Even though samples coated with CS/RE had the lowest pH and TVB-N values (p < 0.05), this coating was not able to pause the protein denaturation after 8 days of storage (p > 0.05) compared to the other treatments. On the other hand, CS/RE coating retarded lipid oxidation by decreasing PV and TBA production in the samples compared to the control up to the end of refrigerated storage (p < 0.05).  相似文献   
53.
Tildipirosin is a semi‐synthetic macrolide antibiotic commonly used in cattle and swine to treat bacterial pneumonia. The objective of this study was to investigate the pharmacokinetic profile of tildipirosin after a single intravenous (i.v.) and subcutaneous (s.c.) administration in healthy lambs. Eighteen lambs were randomly divided into three groups (n = 6 each). Lambs received a single s.c. dose of tildipirosin at 4 and 6 mg/kg b.w. in group 1 and 2, respectively. Lambs in group 3 received a single i.v. dose of tildipirosin at 4 mg/kg b.w. Blood samples were collected at 0, 0.5, 0.75, 1.5, 2, 3, 4, 6, 8, 10, 24, 36, 48 hr, and every 24 hr to day 21, and thereafter at day 28 posttildipirosin administration. The plasma concentrations of tildipirosin were determined using high‐performance liquid chromatography with tandem mass spectrometry detection (LC?MS?MS). All lambs appeared to tolerate both the intravenous and subcutaneous injection of tildipirosin. Following i.v. administration, the elimination half‐life (T1/2), mean residence time (MRT), volume of distribution (Vd/F), and total body clearance (Cl/F) were 119.6 ± 9.0 hr, 281.9 ± 25.7 hr, 521.1 ± 107.2 L, and 2.9 ± 0.5 L/hr, respectively. No significant differences in Cmax (657.0 ± 142.8 and 754.6 ± 227.1 ng/ml), Tmax (1.21 ± 0.38 and 1.35 ± 0.44 hr), T1/2 (144 ± 17.5, 156.5 ± 33.4 hr), and MRT (262.0 ± 30.2 and 250.6 ± 54.5 hr) were found in tildipirosin after s.c. dosing at 4 and 6 mg/kg b.w., respectively. The absolute bioavailability (F) of tildipirosin was 71.5% and 75.3% after s.c. administration of 4 and 6 mg/kg b.w., respectively. In conclusion, tildipirosin was rapidly absorbed and slowly eliminated after a single s.c. administration in healthy lambs. Tildipirosin could be used for the treatment and prevention of respiratory bacterial infections in sheep. However, further in vitro and in vivo studies to determine the efficacy and safety are warranted. To our knowledge, this is the first study to determine the tildipirosin pharmacokinetic parameters in sheep plasma.  相似文献   
54.
Two experiments were conducted to investigate the effects of oral supplementation of the lactic-acid-producing bacterium Enterococcus faecium EF212 alone or in combination with Saccharomyces cerevisiae (yeast) on mediators of the acute phase response in feedlot steers. Eight fistulated steers were used to study the effects of E. faecium alone or with yeast in a crossover design with 2 Latin squares, 4 steers within each square, and 2 periods. The length of each period was 3 wk, with a 10-d adaptation and an 11-d measurement period. The experimental diet contained 87% steam-rolled barley, 8% whole-crop barley silage, and 5% supplement (DM basis). In Exp. 1, treatments were control vs. the lactic-acid-producing bacterium E. faecium (6 x 10(10) cfu/d). In Exp. 2, treatments were control vs. E. faecium (6 x 10(10) cfu/d) and S. cerevisiae (6 x 10(10) cfu/d). The bacteria and yeast supplements were blended with calcium carbonate to supply 6 x 10(10) cfu/d when top-dressed into the diet once daily at the time of feeding (10 g/d). Steers fed the control diet received only carrier (10 g/d). Blood samples were collected from the jugular vein on d 17 and 21 of each period, and serum amyloid A (SAA), lipopolysaccharide binding protein (LBP), haptoglobin, and alpha1-acid glycoprotein (alpha1-AGP) were measured. Supplementation of feed with E. faecium had no effect on concentrations of SAA, LBP, haptoglobin, or alpha1-AGP in plasma compared with those of controls. However, feeding E. faecium and yeast increased (P = 0.02) plasma concentrations of SAA, LBP, and haptoglobin but had no effect on plasma alpha1-AGP. In conclusion, oral supplementation of E. faecium alone had no effect on the mediators of the acute phase response that were measured, whereas feeding of E. faecium and yeast induced an inflammatory response in feedlot steers fed high-grain diets. Further research is warranted to determine the mechanism(s) by which E. faecium and yeast stimulated production of acute phase proteins in feedlot steers.  相似文献   
55.
The present study was conducted to investigate the effects of fenugreek seed meal (FKSM) on growth performance, blood haematological and biochemical factors, survival and stress resistance of the common carp (2.46 ± 0.06 g) fingerlings. Four practical diets containing 0 (control), 0.5%, 1% and 1.5% FKSM were used to feed fish. Fish were fed on the tested diets at a rate of 3% of body weight for 8 weeks. Results indicated that fish fed the control diet had a significantly lower weight gain, specific growth rate and condition factor compared to the other treatments (P < 0.05). Feed conversion ratio decreased significantly in fish fed diets containing FKSM. There were no significant differences in glucose levels, red blood cell count, haematocrit and haemoglobin between treatment groups and the control group (P > 0.05). Significantly lower white blood cells count was observed in fish treatment with FKSM when compared with the control group (P < 0.05). The cholesterol level in group fed supplemented diet by 1% fenugreek significantly lower than other groups (P < 0.05). Total protein levels were significantly higher in all treatments compared to the control (P < 0.05). No mortality was recorded during the feeding trial. In salinity stress experiment, highest survival rate belong to fish fed supplemented diet by 1% fenugreek. These results indicate that FKSM can be considered as a beneficial dietary supplement for improving the growth performance and blood indices of common carp fingerling.  相似文献   
56.
An investigation was accomplished to find the effects of different sizes as a social stress on physiological responses and growth performance of Siberian sturgeon. Juvenile Siberian sturgeon were separated into two sizes (860.88 ± 22.32 g as larger fish and 427.28 ± 2.97 g as smaller fish). Three treatments including large size (L), small size (S), and mixed size (M) were considered. There were equal numbers of large and small fish in the M treatment. Sampling was carried out at 1st week (as a short‐term sampling) and 8th week (as a long‐term sampling) of the experiment. At the end of each sampling, haematocrit, glucose, cholesterol, triglyceride, total protein, lactate, and cortisol were measured. All growth parameters and feed utilization in large fish were not affected in the M treatment compared with the L treatment and also small fish in the M treatment compared with the S treatment. The final biomass in the S treatment was significantly higher than those in the L and M treatments. Haematocrit, glucose, cholesterol, triglyceride, total protein, lactate, and cortisol in the 1st week showed no significant difference with different sizes. However, in the 8th week, only haematocrit increased (by time not size) in the S treatment. Fish in the M treatment in both sizes did not experience the stress condition. Larger and smaller sizes had a positive social interaction; therefore, different sizes of Siberian sturgeon can maintain together without decreasing growth rate and also adverse physiological responses.  相似文献   
57.
The comparative effects of Freund's and Aloe vera gel as adjuvants on the expression of IL‐1β and TNF‐α genes were studied in vaccinated common carp (Cyprinus carpio) with Aeromonas hydrophila bacterin. Fishes were intraperitoneally immunized with A. hydrophila bacterin in combination with Aloe vera gel or Freund's and also without any adjuvant. At day 28 after immunization, all groups were challenged by lethal dose of A. hydrophila (107 cells/fish). Changes in the expression of IL‐1β and TNF‐α genes were evaluated in anterior kidney before challenge and 12, 24, 72 and 7 days postchallenge using quantitative real‐time PCR. Higher expression levels of both genes were observed in all vaccinated groups compared with non‐immunized group. Fishes which received Aloe vera gel showed higher expression of IL‐1β and TNF‐α in relation to animals which vaccinated with or without Freund's adjuvant. We concluded that Aloe vera gel in compared with Freund's adjuvant had a more stimulatory effect on the expression of immune‐related genes in vaccinated common carp and it can use as a novel adjuvant in aquaculture.  相似文献   
58.
Freezing injury is one of the most restrictive dynamics issues that commercial fig producers are fronting. This study was aimed to compare cold hardiness among seven commercial fig cultivars at three different developmental stages. We investigated the association between freezing tolerance and soluble carbohydrate and proline fluctuations during acclimation in the one-year-old fig shoots. Using both electrolyte leakage measurement and tetrazolium stain test LT50 values were calculated, which differentiate freezing tolerance among the studied cultivars. The results showed significant differences among the cultivars at three evaluation stages of dormancy. The average of cold winter resistance in studied cultivars in November, January, and March, were ?16.89, ?20.23, and ?21.35?°C, respectively. LT50 electrolyte leakage, cold hardiness index, significantly varied among the fig cultivars. In November to January, ‘Atabaki’ and ‘Kashki’ cultivars showed the maximum of ?0.11?°C/per day, and the minimum of ?0.01?°C/per day of adaptation rate, respectively. Soluble carbohydrate (sugars) concentrations of shoot samples increased during cold acclimation from November (49?mg/g dry weight (DW)) to January (130?mg/g DW) and then decreased in March (93?mg/g DW). Proline content varied significantly among the cultivars in November and January. High correlations were observed between LT50 values and the soluble carbohydrates content compared with proline. Soluble sugars content might be a better indication of cold hardiness than proline content in fig trees. ‘Atabaki’ cultivar showed a very good resistance to winter freezing in comparison to others cultivars, although it seems to be very sensitive to fall freezing. The outcome of this study can be considered for sustainable production and breeding programs in common figs.  相似文献   
59.
ABSTRACT

The effects of drying parameters on moisture content, water activity, bulk density, water binding capacity (WBC), oil absorption, and color parameters (L*,a*, b*) of foam-mat dried shrimp powders were investigated. Shrimp purees were dried as a foam mat at different drying temperatures (50ºC, 60ºC, and 70ºC) and thicknesses of the foam layer (4 and 8 mm). The experimental results showed that as the temperature increased, the moisture content, water activity, and oil absorption of the samples decreased. However, their solubility increased significantly (P ?0.05). Bulk density of shrimp powder increased with increasing the thickness of the foam layer. Increasing temperature led to increased and decreased WBC with 4 and 8 mm thickness, respectively. Furthermore, the a*, b*, and L* (at 8 mm thickness) decreased with increasing temperature; however, L* increased at 4 mm thickness. Fourier transform infrared (FTIR) spectra showed some major shifts, such as in the region of 1000–1700 cm?1, related to C–O, C–O–C, and C–H band stretching. The differential scanning calorimetry thermograms showed a large peak with a denaturation peak around 72ºC for shrimp proteins.  相似文献   
60.
Spirogyra is commonly found as accessible algae in freshwater areas all over the world. Some medical uses have been reported from this genus. Biological activities of Spirogyra singularis were investigated employing eight in vitro assays. The extract showed different antioxidant activity. IC50 for DPPH radical-scavenging was 4.71 ± 0.11 μg mL?1. The extract showed very strong nitric oxide-scavenging activity with IC50 = 77.3 ± 2.07 μg mL?1, but its Fe2+ chelating ability was weak. The extract also exhibited high antioxidant activity in hemoglobin-induced linoleic acid peroxidation tests and scavenging of hydrogen peroxide. The extract also showed good antihemolytic activity. The total amount of phenolic content in the extract was determined as gallic acid equivalents, and total flavonoid content was calculated as quercetin equivalents. Biological activities may be attributed, at least in part, to the presence of phenol and flavonoid contents in the extract.  相似文献   
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