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991.
Haq Shamshad Ul Kumari Deepa Dhingra Prerna Kothari S. L. Kachhwaha Sumita 《Journal of Crop Science and Biotechnology》2021,24(3):279-292
Journal of Crop Science and Biotechnology - India has a diverse range of agro-ecological conditions which support the cultivation of different rice varieties differing in the adaptation which is so... 相似文献
992.
Jeanne L. Nel Dirk J. Roux Robin Abell Peter J. Ashton Richard M. Cowling Jonathan V. Higgins Michele Thieme Joshua H. Viers 《水产资源保护:海洋与淡水生态系统》2009,19(4):474-485
- 1. Freshwater ecosystems and their associated biota are among the most endangered in the world. This, combined with escalating human pressure on water resources, demands that urgent measures be taken to conserve freshwater ecosystems and the services they provide. Systematic conservation planning provides a strategic and scientifically defensible framework for doing this.
- 2. Pioneered in the terrestrial realm, there has been some scepticism associated with the applicability of systematic approaches to freshwater conservation planning. Recent studies, however, indicate that it is possible to apply overarching systematic conservation planning goals to the freshwater realm although the specific methods for achieving these will differ, particularly in relation to the strong connectivity inherent to most freshwater systems.
- 3. Progress has been made in establishing surrogates that depict freshwater biodiversity and ecological integrity, developing complementarity‐based algorithms that incorporate directional connectivity, and designing freshwater conservation area networks that take cognizance of both connectivity and implementation practicalities.
- 4. Key research priorities include increased impetus on planning for non‐riverine freshwater systems; evaluating the effectiveness of freshwater biodiversity surrogates; establishing scientifically defensible conservation targets; developing complementarity‐based algorithms that simultaneously consider connectivity issues for both lentic and lotic water bodies; developing integrated conservation plans across freshwater, terrestrial and marine realms; incorporating uncertainty and dynamic threats into freshwater conservation planning; collection and collation of scale‐appropriate primary data; and building an evidence‐base to support improved implementation of freshwater conservation plans.
993.
甘蔗光合性状的遗传分析和高光效亲本评价研究 总被引:24,自引:0,他引:24
作物光合作用遗传研究是作物遗传育种研究的一个重要课题和研究方向 ,在水稻、玉米、烟草、大豆等作物上这方面的研究已有不少报道。近年来 ,由于便携式光合作用测定系统的发展和应用使得对甘蔗 F1 代庞大的变异群体在田间快速正确地进行活体测定成为可能。本试验利用 CI-30 1 PS便携式 CO2 气体分析系统活体测量净光合速率 ( Pn)等光合参数 ,探讨甘蔗不同杂交组合的光合遗传特性 ,以评价亲本和指导组合选配 ,为甘蔗高光效育种提供理论依据1 材料与方法1 .1 试验设计以 YN73-2 0 4、CP67-4 1 2和 CP72 -1 2 1 0为母本 ( P1 ) ,Ya71… 相似文献
994.
Daune L. Crankshaw Matthew Zabik Steven D. Aust 《Pesticide biochemistry and physiology》1977,7(6):564-572
The low mixed-function oxidase activity of house fly microsomes has been associated with low cytochrome P-450 content and NADPH-cytochrome c reductase activity. The microsomal cytochrome P-450 content and NADPH-cytochrome c reductase activity could be decreased by the addition of catechol and increased by the addition of cyanide to the homogenates. Similar results were obtained with rat liver microsomes treated with tyrosinase and catechol. During the inactivation of rat liver microsomal enzymes by tyrosinase and catechol, crosslinking of microsomal proteins occurred. These results suggest that the instability of house fly microsomal mixed-function oxidase may be due in part to the action of contaminating tyrosinase on endogenous substrates. 相似文献
995.
Judith G. Makombu Pius M. Oben Benedicta O. Oben Guillaume L. P. Gaudin Isabelle S. Motto Ndelle Makoge 《Journal Of Applied Aquaculture》2013,25(4):310-328
The African River prawn Macrobrachium vollenhovenii is the largest of the local Palaemonidae prawns along the Cameroonian coast and an important target species for fisheries and aquaculture. A preliminary study on larviculture of this species was carried out at the IRAD-AQUASOL hatchery in Kribi, Cameroon. Berried females M. vollenhovenii were obtained from the Lobe and Lokoundje Rivers in the Southern Region, typical Lower Guinea rainforest streams. The larval rearing system consisted of a single recirculation system of four 65 L cylindrical plastic containers connected to a submerged biological filter container (65 L). Experiments were conducted three times in the same condition, with two batches of larvae reared separately in duplicate per experiment, at a density of 40/L, temperature 26°C, and salinity 16%. Larvae were fed from 1 day after hatching until metamorphosis to postlarvae (PL) with newly hatched Artemia nauplii, three times daily at the rate of 5 nauplii per mL water. The number of newly hatched larvae per female body weight unit was not affected by the female size and ranged between 531 to 1349 larvae g?1. The six batches succeeded from hatching to metamorphosis, and the 11 distinct larval stages described for M. rosenbergii were found. Larvae in all the batches developed more or less at the same pace up to stage V. However, a clear difference in the timing of appearance of the developmental stages was observed between batches and individuals of the same batch during the subsequent stages. The transition from stage V to stage VI and from stage IX to stage X was longer than the passage to other stages and seems to be the critical rearing period of M. vollenhovenii. From day 20 onward to sampling, the larval stage index (LSI) showed that larval development of the batch 1 was significantly faster than for all other batches. The time for first appearance of postlarvae was variable between batches (41–74 days), and batch 1 larvae passed through metamorphosis within a shorter span of time (41 days). Survival up to postlarvae was variable among batches, ranging between 3%–9%, and was better in batch 1 (9.31 ± 1.09). The general poor performance in terms of survival and metamorphosis rates of larvae seems to be related to the wild condition of broodstock. To improve performance of larvae, domestication of stock may be necessary. This result is the first recorded success in larviculture of M. vollenhovenii in Cameroon. 相似文献
996.
Traditionally and when using objective gait analysis, horses with and without lameness are most frequently assessed trotting in straight lines in hand. Valuable information can be gained from assessment on the lunge and ridden in walk, trot and canter. No studies have quantified lameness during all aforementioned conditions and gaits at once, despite the rapid recent development in equine gait analysis methods. Objective methodologies, previously confined to gait laboratories, are currently being expanded to field technologies using accelerometers and inertial measurement units (IMUs). This publication aims to describe normal gait and the spectrum of pain-related gait abnormalities and other musculoskeletal adaptations to pain that can be observed in walk, trot and canter during in hand and ridden assessment in straight lines and on a circle on hard and soft surfaces. In addition, it aims to describe briefly how IMUs have been used and areas for further research in the light of what we know from subjective lameness examinations and what is possible with IMUs. 相似文献
997.
Mary E. Gordon PhD Michael L. Jerina BS Randel H. Raub PhD Karen E. Davison PhD J. Kathleen Young PhD 《Journal of Equine Veterinary Science》2008,28(5):289-294
This study tested the hypothesis that feeding an identically formulated, low sugar and starch concentrate in three forms (5-mm extruded [E], 4-mm pellet [P], and 19-mm oval [O]) would affect consumption rate and glucose or insulin responses, or both. Horses received 1.8 kg treatment feed in a randomized, crossover design, with samples taken every 30 minutes for 6 hours for blood glucose and insulin response. Pearson's correlation compared consumption time, insulin and glucose peak, and time to peak insulin and glucose. The pellet (P) elicited a lower (P = .01) glucose concentration at 2.5 hours than O. The pellet also elicited a lower (P = .03) insulin concentration at 5.5 hours than E and O. There were no differences (P > .05) in area under the curve (AUC) insulin, peak insulin, and time to peak insulin for the three treatments. Average insulin concentration was lower (P = .01) for P versus O. There were no differences (P > .05) in average insulin between P and E, nor between O and E. There were no differences (P > .05) in AUC and peak glucose concentration. Time to peak glucose was longer (P = .04) for P versus E. Average glucose concentration was lower (P = .02) for P versus O. Consumption time was longer (P = .03) for O versus P. There was a positive correlation between consumption time and time to peak insulin (r = 0.46, P = .029). Further research on feeding practices, feed forms, and consumption times that affect glycemic response is necessary. 相似文献
998.
我国农产品加工业的发展方向 总被引:7,自引:0,他引:7
论述了我国农产品加工的意义、现状以及今后发展的方向。指出我国当前农产品加工的重点是抓好大宗农产品的加工,并就小麦等九大作物加工发展提出了一些具体的观点与建议 相似文献
999.
使用荧光定量PCR方法,分析了中棉所41、中棉所44、中棉所49和中棉所79等4种不同遗传背景的棉花品种在受到苗蚜为害时,编码类受体蛋白激酶(LRR-RLK)、ATP合酶β亚基(Atpβ)和捕光蛋白复合物Ⅱ(Lhcb2)等3种代谢相关基因的变化情况。在4种棉花品种中,LRR-RLK的表达量变化情况差异较大,该类LRR-RLK的表达量变化与蚜虫的为害有关;Lhcb2基因在中棉所41的子叶和真叶中、中棉所49的真叶中、中棉所44和中棉所79的子叶中对棉蚜的为害应答比较强烈;Atpβ基因在中棉所41和中棉所49真叶中、中棉所44子叶和真叶中应答反应比较强烈,在中棉所79中应答反应较弱。以上试验结果暗示不同的棉花品种应对苗蚜为害可能存在不同的代谢途径。 相似文献
1000.
Evaluation of concentration of voriconazole in aqueous humor after topical and oral administration in horses 总被引:2,自引:0,他引:2
Clode AB Davis JL Salmon J Michau TM Gilger BC 《American journal of veterinary research》2006,67(2):296-301
OBJECTIVE: To determine penetration of topically and orally administered voriconazole into ocular tissues and evaluate concentrations of the drug in blood and signs of toxicosis after topical application in horses. ANIMALS: 11 healthy adult horses. PROCEDURE: Each eye in 6 horses was treated with a single concentration (0.5%, 1.0%, or 3.0%) of a topically administered voriconazole solution every 4 hours for 7 doses. Anterior chamber paracentesis was performed and plasma samples were collected after application of the final dose. Voriconazole concentrations in aqueous humor (AH) and plasma were measured via high-performance liquid chromatography. Five horses received a single orally administered dose of voriconazole (4 mg/kg); anterior chamber paracentesis was performed, and voriconazole concentrations in AH were measured. RESULTS: Mean +/- SD voriconazole concentrations in AH after topical administration of 0.5%, 1.0%, and 3.0% solutions (n = 4 eyes for each concentration) were 1.43 +/- 0.37 microg/mL, 2.35 +/- 0.78 microg/mL, and 2.40 +/- 0.29 microg/mL, respectively. The 1.0% and 3.0% solutions resulted in significantly higher AH concentrations than the 0.5% solution, and only the 3.0% solution induced signs of ocular toxicosis. Voriconazole was detected in the plasma for 1 hour after the final topically administered dose of all solutions. Mean +/- SD voriconazole concentration in AH after a single orally administered dose was 0.86 +/- 0.22 microg/mL. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that voriconazole effectively penetrated the cornea in clinically normal eyes and reached detectable concentrations in the AH after topical administration. The drug also penetrated noninflamed equine eyes after oral administration. Low plasma concentrations of voriconazole were detected after topical administration. 相似文献