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1.
The aim of this study was to determine the synergistic effects of centrifuged egg yolk (EY) and soybean lecithin on post-thaw Caspian horse sperm motility, morphological abnormalities, and assessment of membrane integrity. The centrifuged EY (CEY) was added at concentrations of 2% and 4% to a defined INRA plus 1.25% soybean lecithin extender used to freeze Caspian horse semen. In this experiment, ejaculates collected from each Caspian horse (n = 4) were divided into three equal aliquots and diluted in CEY 2% (INRA2), 4% (INRA4) supplemented, and without any CEY (INRA0) in INRA plus 1.25% soybean lecithin extender, respectively. Thereafter, samples were frozen and thawed following a standard protocol. Sperm cryosurvival was evaluated in vitro by microscopy assessments of post-thaw sperm motility (by means of computer-assisted semen motility analysis [CASA]), acrosomal and other abnormalities (head, mid-pieces, and tail) and plasma membrane integrity (evaluated by HOST). In Caspian stallion, semen extended with INRA2 had significantly higher CASA motility and CASA progressive motility than those extended with the rest of extenders after freezing and thawing (P < .001). There was no significant difference in path velocity (VAP), VCL, and ALH among three groups (P > .05). For straight line velocity (P < .01) and LIN (P < .001), the highest values were obtained from the INRA4 group. The highest percentages of acrosomal and other abnormalities were found in semen diluted in INRA4 (P < .001). In the group frozen INRA2, the percentage of membrane integrity was significantly higher than that of the other groups (P < .001). The use of CEY 2% in combination with soybean lecithin significantly improved Caspian horse semen freezability.  相似文献   
2.
The aim of this study was to evaluate the long‐term effects (7‐month experiment) of diets consisting of fish oil (Kilka fish) and vegetable oil (rapeseed) on the reproductive performance of sterlet sturgeon (Acipenser ruthenus) broodstock. Forty‐five broodstock (990.3 ± 20.05 g) were randomly allocated to three different diet treatments. Three experimental diets were formulated with graded levels of fish oil (100% FO), vegetable oil (100% VO), and a combination of fish and vegetable oil (50% FO + 50% VO). At the end of the 7‐month feeding trial period, the weight gain and final weight were changed significantly different between the treatments (p < 0.05). Broodstock fed the FO + VO diet had higher growth than those fed the only FO or VO diets (p < 0.05). The highest germinal vesicle migration percentage was observed in FO + VO treatment (p < 0.05). The DHA/EPA, DHA/ARA and EPA/ARA ratios in oocyte exhibited a significant difference in the different treatments (p < 0.05). This study indicates that nutrition of broodstock with diet including FO + VO (p < 0.05) can positively affect the growth performance of larvae compared with only FO or VO diets. Furthermore, the high levels of 18:1n‐9, AL and ALA contents in oocytes from broodstock fed VO and the lowest ALA content in oocytes from broodstock fed FO underlined the important role of broodstock diets in the reproductive process and embryonic and/or larval developments of sterlet.  相似文献   
3.
A field study was conducted over two years on maize at Islam Abad Research Station at 34°7′42′′N and 46°27′23′′E and elevation of 1348 m a.s.l in Kermanshah Province, western Iran in order to compare the effects of different irrigation methods and treatments on irrigation water use efficiency, crop yield, yield response factor, pan and seasonal crop coefficients, and other maize parameters. The experiment was a complete randomized block design with three replicates. During the study, irrigation water was applied at 40, 60, 80 and 100% of the maize seasonal water requirement for different surface drip tape (SDT) treatments, and 100% only for conventional furrow irrigation treatments with and without soil and water monitoring. The results showed that by using the above-mentioned different drip tape and surface treatments with soil and water monitoring, maize seasonal irrigation water use savings of 81, 71, 61, 52 and 36% were achieved compared with local conventional furrow irrigation without any soil, water and root monitoring, respectively. The yield response factor (K y), seasonal crop (K c) and pan coefficient (K p) for maize were 0.80, 0.76 and 0.97, respectively.  相似文献   
4.
Crop coefficients of some plants have been provided by the Food and Agricultural Organization albeit crop coefficients for different medicinal plants such as black cumin (Nigella sativa L.) have not been determined so far. Experiments were carried out during 2 years (2010 and 2011) to determine the water requirements, single and dual crop coefficients of black cumin using drainable lysimeter in a semi-arid region. In this study, black cumin water requirement was determined to be 724 mm by water balance method. The reference evapotranspiration was estimated by Penman–Monteith method. Finally, single and base crop coefficients for initial, development, middle and final stages of black cumin growth were determined to be as 0.59, 0.91, 1.29, 0.78 and 0.24, 0.71, 1.09 0.78, respectively. In order to estimate black cumin evapotranspiration by meteorological parameters, multiple regression models were presented. The results of the study showed that the determination of black cumin water requirements with dual crop coefficients had a less difference as compared to the results obtained from regression model. The total dry matter produced was 9.48 kg/ha per mm of irrigation water applied, seed yield was 3.10 kg/ha per mm of irrigation water applied, and oil content was 31 %.  相似文献   
5.
Crossing experiments in Fragaria have frequently resulted in some matroclinal progeny. These have been attributed to either accidental selfing and/or pollen contamination, or apomixis. In this study 202 carefully controlled intra and interspecific crosses in Fragaria were made. No progeny were produced from 164 interploid crosses made between diploids, hexaploids and octoploids but 38 intraploid crosses resulted in 904 F1 plants, of which 42 (4.6%) were found to be morphologically matroclinal. All matroclinal progeny subsequently studied by RAPDs were found to be hybrids and not apomicts. The absence of apomixis among matroclinal progeny in this study casts doubt on previous reports of apomixis in Fragaria. Our results showed that the complete morphological similarity of progeny to the seed parent, even in recessive characteristics, cannot therefore be taken as evidence of apomixis, and may rather indicate the heterozygosity of the pollen parent, emphasising the need to use DNA markers for confirmation of apomixis.  相似文献   
6.
IpaA, IpaB, IpaC, and IpaD are Shigella dysenteriae Ipa operon genes which collectively contribute in invasion to the epithelial cells of the human gut. Among them, IpaD has been demonstrated to play the most crucial role in shigellosis. Noteworthy, due to the more efficient, cost-effective and no need for advanced equipment in comparison with traditional systems, plant-based expression systems are considered as a novel strategy for production of recombinant proteins. As an aim of this research, attempts were carried out to examine and compare IpaD antigen production in three different plant-based platforms, including transgenic tobacco hairy roots and leaves as well as a transient based expression. Furthermore, different signal peptides (i.e. Zera® and Extensin) were also employed in order to improve the production level. Based on TAS-ELISA result, the highest yield of IpaD acquired by ER-derived protein bodies (Zera® ) which was more than 1.29-fold higher as compared with apoplastic space based on TSP% in both transgenic tobacco hairy roots and leaves. Furthermore, transgenic tobacco hairy roots were more abundant than transgenic leaves averaging 0.52 ng of IpaD per μg TSP and with a maximum of 0.94 ng IpaD per μg TSP in the best-performing construct of pBI-ZeCIpaD. Totally, the results of quantitative RT-PCR and TAS-ELISA indicated that the best time point for the production of IpaD using agroinfiltration was 72 h post infiltration and during 72 to 96 hpi, expression levels descended rapidly. To the best of our knowledge, this is the first report representing and combining the potential effects of signal peptides and plant-based expression platforms on stably production of IpaD antigen in transgenic tobacco leaves and hairy roots.  相似文献   
7.
Two-year lysimeter experiments were conducted to determine groundwater contributions by safflower (Carthamus tinctorius L.) crop. The plants were grown in twenty columns each with a diameter of 0.40 m packed with Silty Clay soil. The experiments were carried out in a complete randomized blocks design with four replicates. In each experiment, five treatments were applied by maintaining groundwater salinity to a control treatment with EC 1 dS/m, while the groundwater salinity of the other treatments was 2, 5, 8 and 10 dS/m, and 0.8 m water table level, respectively. The use of groundwater as a part of crop evapotranspiration was characterized by using daily measurements of the water level in Mariotte tubes. The extra magnitude of irrigation water requirement for each treatment was applied by water with EC of 1 dS/m. The results of experiments showed that for different control treatments with 1 dS/m, 2, 5, 8 and 10 dS/m, the groundwater contributions were achieved as 59, 51, 38, 32 and 19% of the total plant water requirements, respectively.  相似文献   
8.
Laboratory and field experiments were conducted to determine the influence of different priming techniques on the germination characteristics and competition of weeds in sugar beet in 2008–2009. Three priming times and four priming methods were used in a laboratory study, and four priming treatments and four redroot pigweed densities (0, 4, 8 and 12 plants m?2) were used in a field study. Sugar beet seeds were treated with polyethylene glycol (PEG 8000), NaCl (1.5 N) and HCl (0.1 N) for 2, 4 and 6 h. Seed characteristics were significantly affected by HCl (0.1 N) treatment for 6 h. In this treatment, the germination percentage was 25 and 9% higher than control and NaCl (1.5 N) treatments after a similar time. An intermediate and low effect has been shown with NaCl (1.5 N) and PEG 8000 seed priming, respectively. Sugar beet root yield was reduced by 13, 54 and 89% compared with control treatment (without weed) at redroot pigweed densities of 4, 8 and 12 plants m?2, respectively. Sugar beet seeds primed with HCl (0.1 N) for 6 h gave a higher root yield than unprimed seeeds and the other primed seeds treatments. Overall, the results showed that weed control can significantly increase sugar beet yield and the seed priming technique can be used for weed control.  相似文献   
9.
Lysimetric experiments were conducted to determine the contribution made by groundwater to the overall water requirements of safflower (Carthamus tinctorius L.). The plants were grown in 24 columns, each having a diameter of 0.40 m and packed with silty clay soil. The four replicate randomized complete block factorial experiments were carried out using different treatment combinations. Six treatments were applied during each experiment by maintaining groundwater, with an EC of 1 dS m?1, at three different water table levels (0.6, 0.8 and 1.10 m) with and without supplementary irrigation. The uptake of groundwater as a part of crop evapotranspiration was measured by taking daily readings of the water levels found in Mariotte tubes. The supplementary irrigation requirement for each treatment was applied by adding water (EC of 1 dS m?1). The average percentage contribution from groundwater for the treatments (with and without supplementary irrigation under water table levels of 0.6, 0.8 and 1.10 m) were found to be 65, 59, 38% and 72, 70, 47% of the average annual safflower water requirement (6,466 m3 ha?1). The increase in groundwater depths under supplementary irrigation treatments from 0.6 to 0.80 and 1.10 m caused seed and oil yield reductions of (7, 23.10%) and (48.23, 65.40%), respectively.  相似文献   
10.
Thyme (Thymus vulgaris) is a subshrub from the lamiaceae family with plants that are rich in essential oils and antioxidative phenolic substances. The aim of the study was to investigate the effect of dietary thyme and fish oil supplementation on the semen characteristics of miniature Caspian horse. Sixteen stallions were randomly allocated into four groups and received four different diets: unsupplemented control diet, supplemented with fish oil at 2.5% dry matter intake (DMI), supplemented with fish oil (2.5% DMI), and thyme (0.02% DMI), and supplemented with thyme (0.02% DMI). All experimental diets were formulated according to National Research Council (1998). Semen was collected at 0, 30, 60, and 90 days. The semen samples were cooled and preserved at 5°C. Cooled diluted semen samples were evaluated in vitro by microscopic assessments of chilled sperm motility, acrosomal and other abnormalities (head, midpieces, and tail), viability (evaluated by Eosin–nigrosin), and plasma membrane integrity (evaluated by hypo osmolarity swelling test), and the level of malondialdehyde (MDA) was determined during cool storage 0, 24, and 48 hours after collection. The results showed that total and progressive sperm motility and plasma membrane integrity and functionality in all groups were significantly decreased with increasing storage time. On the other hand, the level of MDA in all groups was significantly increased with increasing storage time. Also, the results showed that most sperm quality parameters in this study were significantly higher in fish oil–thyme and fish oil group compared with thyme and control groups after 24 and 48 hours of storage at 5°C. We concluded that dietary supplementation of fish oil and thyme can improve sperm quality in miniature Caspian stallions during storage in cool condition via increasing total and progressive motility and plasma membrane integrity and functionality. More advances in vitro evaluations and artificial insemination are required to reveal the exact effects of thyme on miniature Caspian stallion sperm quality and its fertilizing ability.  相似文献   
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