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Current study was carried out to examine the protective effects of quercetin against toxicity induced by hydrogen peroxide in rooster semen in vitro. Semen samples were collected from ten roosters (Ross 308 broiler breeder males, 32 weeks old) twice a week by abdominal massage method. Samples with ≥70% progressive motility were selected, pooled, diluted and used for the study. Experimental groups consisted of negative control, control that received solvent of quercetin, H2O2 (40 μM) and combination groups which incubated with constant dose of H2O2 (40 μM) plus various levels of quercetin (20, 40 and 80 μM). Measurement of total hydroperoxide (HPO), malondialdehyde (MDA), nitric oxide (NO), total antioxidant capacity (TAC) and superoxide dismutase activity as well as routine sperm tests were done at 0, 24 and 48 hr of storage at 4°C. Results revealed that exposure to hydrogen peroxide significantly increased HPO (138.43 ± 7.32 vs. 66.08 ± 3.97 μmol/g protein), MDA (7.21 ± 0.08 vs. 5.71 ± 2.16 μmol/g protein) and NO (0.367 ± 0.013 vs. 0.215 ± 0.011 μmol/g protein) levels and decreased sperm progressive motility (27.28 ± 1.21 vs. 47.49 ± 1.29%), and amounts of TAC (11.49 ± 0.39 vs. 15.70 ± 0.79 mmol/g protein) compared to control at 24 hr (p < 0.05). Changes at mentioned variables were repeated at 48 hr of storage. Also, co‐administration of quercetin (especially at 40 and 80 μM) with hydrogen peroxide restored the toxic effects of hydrogen peroxide on rooster semen parameters such as primary and secondary lipid peroxidative indicators and other evaluated variables. The study concluded that rooster semen enrichment with quercetin would protect lipid peroxidative and nitrosative hydrogen peroxide‐mediated damage during cold liquid storage of rooster semen.  相似文献   
3.
Spermatozoa concentration, ionic composition, osmolality, glucose and total protein contents of seminal plasma and sperm motility were determined in Barbus sharpeyi (Cyprinidae, Teleosotei). Spermatozoa concentration ranged from 9.77 to 20.20 × 109 spermatozoa mL?1. Osmolality (mOsmol kg?1) and ionic contents (mM L?1) of the seminal plasma were 274.5±9.0, 70.0±3.4 Na+, 28.8±0.9 K+, 101.7±3.1 Cl?, 0.9±0.1 Mg2+ and 2.1±0.1 Ca2+ respectively. Total protein and glucose were 5.3±0.2 g L?1 and 76.7±4.3 mM L?1 respectively. Sperm motility was initiated in a hypo‐osmotic condition, composed of either an ionic (KCl or NaCl) or a non‐ionic (sucrose) activation medium. Duration of sperm motility was very short: <2 min after activation in distilled water. Percentage of motile spermatozoa was significantly higher in an activation medium containing NaCl compared with that of distilled water. An activating medium containing NaCl or KCl higher than 150 mM or sucrose higher than 275 mM totally inhibited the activation of sperm motility. Immediately after sperm activation, wave(s) propagated along the flagellum, but waves were restricted to the proximal part of the flagellum (close to the head) at 1 min post activation. Studied characteristics in the present study were compared with those of other cyprinids for understanding inter‐species differences.  相似文献   
4.
Background: Pseudomonas aeruginosa is one of the opportunistic pathogens causing frequent hospital-acquired life-threatening infections in mechanically ventilated patients. The most significant virulence factor of P. aeruginosa is T3SS. PcrV is an important structural protein of the T3SS. Methods:In the current investigation, a recombinant scFv mAb against the PcrV protein was expressed in EnBase® (fed-batch) cultivation mode. The pETiteTM N-His SUMO Kan vector, including anti-PcrV scFv gene, was transformed into Escherichia coli (BL21) cells. The expression and solubility of anti-PcrV scFv protein were investigated at two different temperatures (25 °C and 30 °C) and at different induction times (4, 6, 8, 12, and 24 hours). Results:Increased efficiency was achieved by EnBase® compared to LB broth; owing to the slow release of glucose, the maximum level of solubility and total protein expression was observed in EnBase® cultivation system at 30 °C and 24 h post induction. Furthermore, IC50 for anti-PcrV scFv protein was determined to be approximately 7 μg/mL. Conclusion:Anti-PcrV scFv produced in this study showed promising in vitro results, protecting RBC from lysis by P. aeruginosa (exoU+). Key Words: Fed Batch, recombinant protein, Pseudomonas aeruginosa, scFv  相似文献   
5.
Changing climatic conditions in north-western Europe are accompanied by occasional extreme weather conditions. This requires breeding of winter oilseed rape cultivars which are resilient to diverse abiotic stress factors, e.g. frost, drought and heat. The degree of vernalization requirement of winter oilseed rape has been found to be related to frost tolerance and winter hardiness. Shoot elongation before winter in particular has been identified as one decisive factor for frost tolerance in winter oilseed rape. However, the relationship between vernalization requirement and shoot elongation before winter is not known. In the present study the genetic variation for shoot elongation before winter and vernalization requirement of 19 genetic diverse breeding lines and cultivars were analyzed. Autumn and spring sown field experiments in multiple environments were performed to determine shoot elongation before winter and vernalization requirement, respectively. In spring sown field experiments, genotypes with a low vernalization requirement were characterized by the occurrence of long bolting plants with flower buds. Large and significant genotypic variation was found for shoot length in the autumn sown and spring sown environment. Broad sense heritability was quite high for shoot length in the spring sown environment (h2?=?97%), whereas it was only of medium size for shoot length before winter (h2?=?62%). Although the correlation between shoot length before winter and shoot length in the spring sown environment was positive (Spearman’s rank rS?=?0.48*), a number of genotypes with reduced shoot elongation before winter and low vernalization requirement were identified. Results indicate that genotypes with a reduced shoot elongation before winter independent of their vernalization requirement can be selected in breeding programs.  相似文献   
6.
The mucoadhesive Chitosan (CS) nanofibers as a drug delivery system were developed. Chitosan was modified via the immobilization of thiol groups from L-cysteine as a mucoadhesive reagent. The mucoadhesive properties of the chitosan nanofibers were evaluated by tensiometer set and via tensile studies. Drug and mucoadhesive agent loading lead to decrease diameters and increased porous of nanofibers. The release of Tetracycline (Tet) and Triamcinolone (Tri) were increased with increasing immersion time and it became constant at long immersion times. Mucoadhesion studies were done at pH 2–7 and in pH 6 maximum mucoadhesive properties observed. Release studies demonstrated a sustained release of both drug continued up to 48 hours. Microbial studies were performed on the nanofibers. The drug delivery system represented a novel tool for improve the therapeutic efficacy of various drugs that are poorly absorbed from the gastrointestinal tract. Also it is an efficient system for treatment of oral ulceration.  相似文献   
7.
This study was undertaken to assess the effects of feeding European seabass (Dicentrarchus labrax) canola oil-added diets on growth, health status and liver and intestine histomorphology. Seabass (56.18 ± 0.16 g initial body weight) were fed one of three fish meal-based diets with ~48 % crude protein and ~16.0 % lipid, combining fish oil (FO) and canola oil (CO) for 12 weeks. The diets contained: zero (control, CTRL), 45 (CO50) or 63 (CO70) g CO kg?1 assigned in triplicates to three dietary groups. The results indicated that neither dietary oil type (FO or CO) nor CO level adversely affected (P > 0.05) the growth, feed utilization or major blood constituents’ composition as an indicator of the overall health status of fish. Despite the CO diets influence on head kidney macrophage activity being unappreciable (P > 0.05), there was a reducing trend with an increase in CO level incorporation. The CO70 diet induced a minor fat infiltration in hepatocytes and leucocytes infiltration, hyperplasia of the basal nuclei and supranuclear vacuolization of the enterocytes of the distal intestine. The present observations suggest that it is possible to incorporate up to 63 g CO Kg?1 in the feed for European seabass juveniles without major negative effects on growth, health status or liver and intestinal histomorphology.  相似文献   
8.

Background:

In previous studies, the neuroprotective effect of 17β-estradiol in diffuse traumatic brain injury has been shown. This study used ICI 182,780, a non-selective estrogen receptor antagonist, to test the hypothesis that the neuroprotective effect of 17β-estradiol in traumatic brain injury is mediated by the estrogen receptors.

Methods:

The ovariectomized rats were divided into eight groups. Brain injury was induced by Marmarou’s method. Estrogen was injected 30 minutes after traumatic brain injury, and ICI 182,780 was injected before traumatic brain injury and also before estrogen treatment. In one group only ICI 182,780 was injected. The brain water content and Evans blue dye content were measured 24 and 5 hours after traumatic brain injury, respectively. The neurologic outcomes and intracranial pressure were assessed before, 4, and 24 hours after traumatic brain injury.

Results:

Brain water content and Evans blue content were less in estrogen-treated group comparison to vehicle group. ICI 182,780 eliminated the effects of estrogen on brain edema and brain blood barrier permeability. Intracranial pressure was increased significantly after trauma, and estrogen decreased intracranial pressure at 4 and 24 hours after traumatic brain injury in comparison to vehicle. This inhibitory effect was also eliminated by treatment with ICI182,780. ICI 182,780 also inhibited the estrogen induced increase in neurologic outcomes following traumatic brain injury. However, the use of ICI 182,780 alone had no neuroprotective effect after traumatic brain injury.

Conclusion:

The results suggest that classical estrogen receptors have probably a role in the neuroprotective function of estrogen following traumatic brain injury.Key Words: Estrogens, Intracranial pressure (ICP), Brain edema  相似文献   
9.
18 soybean genotypes were examined to investigate the relationships between some principal attributions of morphology with seed yield per soybean, by Random Complete Block Design (RCBD) study. This study was also carried out three replicates to gain reliable results. The results of variance analysis indicated that, there were significance differences among all soybean genotypes. Moreover, the results of correlated analysis revealed that biological yield (0.96), harvest index (0.92), and number of branches (0.92) had the uttermost correlation with seed yield. To data factor analysis, four independent variables justified 99 percent of all data. The first variable, seed yield, justified 96 percent of entire variance. Multiple-Regression Model with method Analytical Regression Model (step-by-step) was utilized to examine soybean seed yield. This model proved that biological yield, thousand seed weight, and harvest index entered into model respectively and justified 98.85 percent of variation of seed yield. Correlated coefficients of considered attributions were equal to 0.96, 0.78, and 0.92, respectively. All of these indexes had significant at 1% in statistical process. Therefore, these traits can be notability used in soybean breeding programs. Also, accordance to cluster analysis, the sample was divided into three groups.  相似文献   
10.
This investigation was conducted to explore the effects of salt types with different concentrations on germination and growth parameters of flax seeds. The experiment was set out as a factorial experiment based on a completely randomized design with three replications. We used six kinds of salts (NaCl, CaCl2, CaCO3, Na2SO4, Na2CO3 and KCl) with concentrations of 0, 50, 100 and 200 mM. According to the results, the inhibitory effects of the five salt types differed substantially, especially in the case of CaCO3, Na2CO3 and Na2SO4. Inhibitory effects of these salts were very strong compared to those of NaCl and CaCl2. Germination of flax seeds by various salts was in the order of NaCl > CaCl2 > KCl > Na2CO3 > Na2SO4 > CaCO3. The effect of salt concentration was obvious, too. Seeds of flax were able to germinate even in 200 mM NaCl, but they only germinated in distilled water or at very low CaCO3, Na2CO3 and Na2SO4 concentrations (50 mM).  相似文献   
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