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311.
Leptin is thought to be not only a satiety factor but also a stimulator of angiogenesis. We examined leptin, PPARγ2, and vascular endothelial growth factor (VEGF) expression in bovine intramuscular preadipocyte (BIP) cells during proliferation. The cells were seeded at 0.85 × 104 cells/cm2 and collected every day until the fifth day after passage. Leptin mRNA was present in the cells between days 2 and 4, as indicated by RT-PCR analysis. Western blot analysis showed a band for leptin at approximately 16 kDa on all of the days during growth, and the cytoplasmic concentration of leptin was highest on day 2 and decreased gradually thereafter. A PPARγ2 band at approximately 54 kDa was also observed on all days. The concentration was highest on day 2 and decreased thereafter, which is similar to the expression pattern of leptin. In constant, the expression level of VEGF protein did not change while in culture. We have demonstrated that BIP cells can synthesize both leptin and PPARγ2, with maximal synthesis occurring during maximal proliferation. Given the role of leptin in angiogenesis, we speculate that leptin is involved in the neovascularization of adipose tissue, because new organization of adipose tissue requires the growth of new blood vessels. 相似文献
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Kazuki Saito Amadou Touré Aminou Arouna Rose Fiamohe Drissa Silué John Manful 《Plant Production Science》2013,16(4):428-442
ABSTRACTInformation on comprehensive evaluation of agricultural innovations is often limited. This study provides an overview of multidisciplinary evaluation of a lowland rice variety, WITA 9 (released in Côte d’Ivoire in 1998), with respect to its agronomic performance, grain quality, resistance to diseases, adoption by farmers, impact on productivity and farmers’ income, and marketability. WITA 9 had the highest paddy yield among the tested varieties including an international check (IR 64) and recently developed varieties adapted to this country. WITA 9 had a higher amylose content (26–28%) than others tested. This study confirmed its resistance to bacterial leaf blight, Rice yellow mottle virus (RYMV), and rice blast. A household survey showed that the adoption rate was 24%, its paddy yield advantage was 0.7 t ha–1, and its adoption increased farmer’s income by US$ 91 ha–1 per season. A market study showed that consumers’ willingness to pay was higher for WITA 9 than any other locally produced rice variety and comparable to imported rice in one of two markets. We conclude that WITA 9 is an ideal innovation for enhancing productivity and rice import substitution in Côte d’Ivoire. An effective seed delivery system and enhancing farmers’ and consumers’ awareness of this variety are vital for accelerating impact. 相似文献
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Williams PA English RJ Blanchard RL Rose SA Lyons L Whitehead M 《Pest management science》2008,64(5):497-504
BACKGROUND: Water-soluble polymers are increasingly added to herbicide and pesticide formulations at very low concentrations (100-1000 mg L(-1)) in order to control the spray characteristics, notably to reduce spray drift and influence droplet bounce. The incorporation of polymeric adjuvants improves the efficacy of the spray solutions, thus enabling crop growers to maximise the performance of agrochemical sprays at lower dose rates of active ingredient. It is important to establish a fundamental understanding of how polymers influence the processes involved in droplet deposition.RESULTS: The shear and extensional viscosities of a series of high molecular mass (M(w)) poly(acrylamides) (M(w) approximately 10(6)-10(7)) have been determined at very low concentrations (100-1000 mg L(-1)). The polymer solutions demonstrated typical shear thinning characteristics under shear, and strain hardening behaviour under extension above a critical strain rate. The presence of the polymers was shown to increase the size of droplets produced in atomisation using an agricultural spray nozzle, as measured by laser diffraction. This was attributed to the increase in the extensional viscosity at the strain rates generated under pressure in the spray nozzle and was a function of both polymer concentration and M(w). In addition, the presence of polymer was found to have a significant influence on droplet bounce.CONCLUSIONS: The presence of very low concentrations of high molecular mass poly(acrylamides) significantly influences the size of droplets formed on atomisation and subsequent bounce characteristics. Large extensional viscosities generated above a critical strain rate are responsible for both processes. 相似文献
315.
George E. Inglett Devin J. Rose David G. Stevenson Diejun Chen Atanu Biswas 《Cereal Chemistry》2009,86(6):661-664
The purpose of this study was to determine the efficacy of extracting phenolic compounds with antioxidant activity from distillers' dried grains with solubles (DDGS) with water, 50% aqueous ethanol, and absolute ethanol, using microwave irradiation or a water bath at various temperatures. DDGS was extracted for 15 min with each solvent while heating at 23, 50, 100, and 150°C by microwave irradiation or in a water bath at 23, 50, and 100°C. Phenolic content of extracts increased with increasing temperature to a maximum of 12.02 mg/g in DDGS extracts that were microwave irradiated in water or with 50% aqueous ethanol at 150°C. Antioxidant activity range was 1.49–6.53 μmol of Trolox equivalents/g of DDGS. Highest antioxidant activities were obtained from 50% aqueous ethanol extracts at all temperatures, and water extracts that were heated at 100 and 150°C. These data indicate that DDGS extracts with high phenolic content and antioxidant activity can be obtained from DDGS, particularly with the use of water or 50% ethanol and high temperature (100 or 150°C). This may be valuable to ethanol manufacturers, livestock producers, and food and nutraceutical companies. 相似文献
316.
Ismail M EI-Karran Y A 《饲料博览》2009,(7):44-44
试验旨在测定短期生长激素(bST)对奶牛产奶量与肾上腺素变化导致的非酯化脂肪酸(NEFA)的相关性。选择26头(58±5.4)日龄的经产荷斯坦奶牛,每日皮下注射盐溶液7d:然后皮下注射bST 20mg·d^-1 14d。分别在盐溶液处理的第7天及bST处理的第14天给奶牛静脉注射肾上腺素1.4μg·kg^-1体重。并在肾上腺素注射之前与之后分别采集血样。注射盐溶液的奶牛与注射bST2周的奶牛产奶量差异(MYR)显著(-0.4—+8.0kg·d^-1)。MYR不仅与经盐溶液处理和bST处理2周的非酯化脂肪酸基础浓度密切相关,而且也与肾上腺素导致的非酯化脂肪酸高于其原有值有关。负能量可反应出奶牛脂肪组织生理特性有着本质的不同,而MYR大的奶牛肾上腺素导致的非酯化脂肪酸的解脂作用是否能反应奶牛的更大负能量还有待于进一步研究。 相似文献
317.
Stable integration and expression of a cry1Ia gene conferring resistance to fall armyworm and boll weevil in cotton plants 下载免费PDF全文
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Diseases of the nasal cavity and sinuses can be frustrating problems for owners and veterinarians alike. Initial physical examination and routine blood work are often unrewarding in directing the clinician at a diagnosis. Diagnostic imaging can help characterize the disease process and direct treatment or further diagnostics. Radiographs of the skull are an excellent first-line diagnostic step in the analysis of nasal disease. The following article reviews basic techniques, positioning, and interpretation of radiographs of the nasal cavity and paranasal sinuses. 相似文献