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31.
Biocalcium powders, Bio-cal-H, and Bio-cal-A, obtained from non-alkaline treated and alkaline treated salmon frame were characterized. Glycine was the dominant amino acid (216.45–321.80 mg/g), followed by glutamic acid (102.52–110.38 mg/g), proline (72.96–96.10 mg/g), and hydroxyproline (72.98–83.75 mg/g) in both biocalcium powders. Bio-cal-H possessed a high abundance of volatile compounds such as 2-propanone, acetonitrile, and 2-butanone than Bio-cal-A. Bio-cal-A had a higher solubility in in vitro simulated gastrointestinal tract than Bio-cal-H and CaCO3 (P < .05). However, transportation of calcium across Caco-2 cell monolayer of Bio-cal-H was higher than Bio-cal-A and CaCO3 (P < .05). Overall, biocalcium could serve as a promising source of calcium supplementation.  相似文献   
32.
There is a renewed interest in research and use of glandless (free of gossypol) Upland cotton (Gossypium hirsutum L.) that can produce edible seeds for human food and animal feed. However, there was a lack of information on yield potential of existing glandless germplasm since intermittent breeding activities for glandless cotton were stopped in the U.S. before 2000. The objectives of the present study were to test obsolete and exotic glandless germplasm for possible production and evaluate progress in direct pedigree selection within the existing glandless germplasm in eight field tests. In multiple tests, the glandless cotton Acala GLS yielded only 65–80 % lint of the glanded control Acala 1517-08 and 46–75 % lint of commercial transgenic cultivars. Most of obsolete glandless germplasm and their selections yielded <70 % of Acala 1517-08 and only three selections yielded 82–89 % of the control. Genetic variation in yield and fiber quality traits was seen from significant differences between selections within the same glandless germplasm, indicating the existence of residual genetic variation. Most importantly, three selections from exotic glandless germplasm out-yielded Acala 1517-08 by 4–9 %, one of which had desirable fiber quality traits. These promising glandless lines with comparable yields to commercial cotton make it possible to revitalize the glandless cotton industry. More field tests will be needed to evaluate their yield potential and adaptability in the U.S. Cotton Belt.  相似文献   
33.
Glandless cotton can be grown for cottonseed free of toxic gossypol to be used as food and feed for non-ruminant animals. However, one of the most important limiting factors preventing its commercial production is its higher insect damage than conventional glanded cotton. Thrips is the one of the most important insect pests in the early growing season that may cause yield losses. In this study, 28, 29, 26, and 2 glandless cotton lines were compared with glanded control Acala 1517-08 and other glanded lines for resistance to the Western flower thrips, Frankliniella occidentalis (Pergande) in four replicated field tests each containing 32 genotypes. In the same field, 28 glanded commercial cultivars and 78 glanded breeding lines were compared with Acala 1517-08 and Acala 1517-99 in three other tests with 32 genotypes each. The experimental layouts allowed a comprehensive comparative analysis of thrips resistance within and between glandless and glanded cotton. Overall, glandless cotton had similar or lower thrips damages than glanded cotton, indicating that the glandless trait may serve as a genetic factor for suppressing thrips damage. As compared with Acala 1517-08 which represented one of the most thrips resistant genotypes among glanded cotton tested, glandless Acala GLS and many selections from glandless germplasm were more resistant, while some were similar to Acala 1517-08, indicating that genetic factors other than the glandless trait also affect thrips resistance in cotton. The estimates for broad-sense heritability for thrips resistance were moderate, indicating that thrips resistance is selectable. This is corroborated by the identification of many thrips resistant lines from a cross between Acala 1517-08 and Acala GLS. This study has laid a foundation for a more detailed study using most resistant lines with desirable agronomic traits in multiple environments.  相似文献   
34.
Spindle movements, including spindle migration from the center to the cortex of oocytes during first meiosis and spindle rotation during second meiosis, are required for asymmetric meiotic divisions in many species. However, little is currently known in relation to the rat oocyte. To explore how spindles move and the mechanism controlling spindle movements in rat oocytes, we observed the spindle dynamics during the two meiotic divisions in the rat oocyte by confocal microscopy. Drugs that depolymerize microtubules or microfilaments were employed to further determine the roles of these two cytoskeletons in spindle movements. The results showed that peripheral spindle migration took place during first meiosis and spindle rotation took place during second meiosis in the rat oocytes. Microfilament inhibitor inhibited both spindle migration and spindle rotation, and depolymerization of microtubules inhibited spindle rotation. Severe depolymerization of microtubules inhibited spindle migration, while migration was achieved by partial but not complete depolymerization of microtubules. We thus conclude that microfilaments are important for both spindle migration and spindle rotation and that spindle microtubules are essential for spindle movements in rat oocytes.  相似文献   
35.
This study examines the socio-economic and financial performances of irrigation projects under the Ogun-Oshun River Basin and Rural Development Authority (O-ORBRDA) in Nigeria. Primary data on the farming activities of the project farmers during the 2001/02 seasons and the projects' records for the period of 1995/96 to 2001/02 were summarised into socio-economic and financial performance indicators. In the Sepeteri Project, a revenue recovery level of 96% was estimated. The project is not financially viable as only 29% of its recurrent expenditure is covered. The farmers do not show commitment to making the project successful. An approximate 67% social capacity level was estimated. The relative irrigation cost and profit indexes do not show sufficient evidence that farmers would prefer irrigation farming to rain-fed farming. The Itoikin Project records a lower revenue recovery level of 75%. The project covers about 50% of its recurrent expenditure. In addition, the farmers do not appear to have a commitment to making the project successful, with a 33% social capacity level. A number of problems may be the causes of unprofitable irrigated cropping. If government increases the subvention, the O-ORBRDA prioritises irrigation service in disbursing the subvention to the projects, and the project manages the risks in the project sites, conscientises and incorporates the intended beneficiaries into managing the projects, the projects would be equipped to supply more irrigation services thereby making it more profitable and encouraging more participation of the intended beneficiaries. This would improve the socio-economic and financial performance of the projects.  相似文献   
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