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151.
152.
鲜枣的贮藏   总被引:2,自引:0,他引:2  
鲜枣营养丰富 ,含有比一般水果高一倍多的糖分及较多的蛋白质、脂肪、铁、磷、钙等物质 ,有很高的营养价值和食疗功能。但鲜枣采后在自然条件下存放 ,仅有几天的鲜脆期 ,果肉会很快软化变褐 ,失去商品价值。研究表明 ,通过控制适宜的贮藏环境 ,可使鲜枣贮藏期在60天以上 ,有的品种在贮藏90天以上时 ,脆果率仍超过70%。现将适宜鲜枣贮藏的主要条件介绍如下。1.采收时间和外观采收成熟度对贮藏寿命影响显著 ,成熟度越低越耐贮 ,但果实失水率要快于成熟度高的果实。全红果(100%着色)、半红果(约50%着色)、初红果(着色25 %…  相似文献   
153.
Milrinone, a therapeutic agent for acute congestive heart failure, has both inotropic and vasodilatory effects, but investigations of these effects of milrinone were almost all conducted under normoxia, and few reports have investigated how milrinone affects the hemodynamics and redistribution of regional blood flow under severe hypoxia. By using colored microspheres, we investigated how milrinone affects hemodynamics and the redistribution of regional blood flow under severe hypoxia. Twelve healthy mongrel dogs were divided into 2 groups. The milrinone group was infused with milrinone cumulatively at 25, 75 and 250 microg/kg for 5 min each. The intact group was infused with saline instead of milrinone. We measured the hemodynamics and cerebrum, cerebellum and kidney blood flow in both groups. Both groups were inspired with 10% oxygen. Milrinone induced significant decrease in mean pulmonary artery and pulmonary vascular resistance, compared with the intact group. In both groups slight decreases in mean arterial pressure, systemic vascular resistance and double-product were seen. In regional blood flow, milrinone-induced increases in blood flow were seen in the cerebrum, cerebellum, and especially in the kidneys. Milrinone's vasodilatory effects were sufficient even under hypoxia. And milrinone increased regional blood flow slightly in the cerebrum and cerebellum, and significantly in the kidneys. These results suggested that milrinone protects against hypoxia-induced organ damage especially in the kidneys. In addition, milrinone is very potent in improving severe congested hemodynamics which complicates hypoxic pulmonary vasoconstriction.  相似文献   
154.
中国葡萄的气候区划研究(英文).   总被引:2,自引:0,他引:2       下载免费PDF全文
葡萄是中国的主要果树之一,1997年生产葡萄203万吨.本文讨论了中国葡萄的地理分布与气候区划.应用地图叠置法,将全国划分为8个农业气候区.为了防御和减轻气象灾害对葡萄栽培造成的损失,应当选择对葡萄栽培最适宜(Ⅰ),适宜(Ⅱ,Ⅲ)或较适宜(Ⅳ,Ⅴ)的区域种植适宜的葡萄品种.  相似文献   
155.
Following a sustained spill-over event from dogs to foxes, fox rabies spread rapidly in the Aegean region, Turkey. In order to control the outbreak a program of oral vaccination of foxes against rabies was introduced. In the selected vaccination area three annual campaigns between 2008 and 2010 were undertaken during the winter months whereby the vaccine baits were distributed exclusively by plane using a density of 18 baits per km2. Subsequently, fox rabies cases were reported only from locations bordering the non-vaccinated areas. Hence, it was shown that fox rabies control by means of oral rabies vaccination is feasible in Turkey. However, for the progress towards the elimination of fox-mediated rabies in Turkey to be maintained, it is necessary that political and financial support is secured to extend oral vaccination where infected foxes remain.  相似文献   
156.
Milled wood and milled wood lignin (MWL) samples were subjected to DFRC and thioacidolysis. Despite the fact that both methods selectively cleave aryl ether bonds, substantial differences in results were obtained. Lignin thioacidolysis gave total molar yields of degradation monomer products in the range of 3.5-7 mol % higher than DFRC. GPC analysis showed that the thioacidolysis-treated lignin was degraded to a lower average molecular weight than that treated by DFRC. Contrary to results reported for lignin model compounds, these results indicate that the DFRC method does not completely or efficiently degrade the lignin polymer. In fact, the DFRC-degraded lignin retained much of the characteristics of the original MWL. Elemental analysis revealed the presence of bromine in the DFRC-treated lignin, and two-dimensional (1)H-(13)C HMQC NMR spectroscopy showed the presence of beta-O-4 linkages in the DFRC-treated lignin. No beta-O-4 interunit linkages were detected in the thioacidolysis-treated lignin. These results are consistent with the lower monomer yields and the higher average molecular weight of the DFRC-treated lignin and indicate inefficiency in the chemistry of the method, probably due to steric constraints of the polymeric nature of lignin.  相似文献   
157.
沛县杨屯镇大山湾村有位年近五旬的农民叫王新佳,全家8口人,劳力4人,靠发展养殖乌鱼率先脱贫致富,在当地传为佳话。1995年,王新佳和妻子、儿女们在种好责任田的同时,凭着靠近日出斗金的微山湖自然资源丰富的优势,于当年筹集资金2万元,在湖滩地上开挖2个鱼池,面积...  相似文献   
158.
Heterologous conjugates of wheat arabinoxylan and beta-casein were prepared via enzymatic cross-linking, using sequential addition of the arabinoxylan to a mixture of beta-casein, peroxidase, and hydrogen peroxide. The maximal formation of adducts between the beta-casein and the feruloylated arabinoxylan was reached at a protein-to-arabinoxylan ratio of 10:1, in combination with a molar ratio hydrogen peroxide to substrate of 2:1 and a molar protein-to-enzyme ratio between 10(2) and 10(4). The protein-arabinoxylan adducts were separated from the arabinoxylan homopolymers by size exclusion and anion exchange chromatography. The molar ratio protein:arabinoxylan in the purified conjugates varied between 0.1 and 5.6. This is the first report on the large-scale enzymatic preparation of heterologous protein-arabinoxylan conjugates.  相似文献   
159.
The effect of pH on the thermal stability of potent roasty odorants, 3-mercapto-3-methylbutyl esters, in coffee drinks was investigated. The concentration of 3-mercapto-3-methylbutyl formate in the coffee drink was drastically decreased during the heat processing. However, the residual ratio of this compound in the coffee drink adjusted to pH 5.0 was higher than that of pH 6.5. On the other hand, the residual ratios of 3-mercapto-3-methylbutyl acetate showed high values in the coffee drinks adjusted to both pHs. In the pH range of 3-7, the residual ratios of 3-mercapto-3-methylbutyl formate in aqueous model solutions varied depending on the pH value. It had a thermal stability maximum at pH 4.0, while 3-mercapto-3-methylbutyl acetate showed stability during heat processing over all the pH values tested. In addition, the residual ratios of the formate and acetate esters, which were composed of various alcohol derivatives, showed the same tendency as that of the 3-mercapto-3-methylbutyl esters. These results suggested that the low thermal stability and pH dependence of 3-mercapto-3-methylbutyl formate are based on the structure of the formate ester.  相似文献   
160.
近来,Matthews阐述了用小鼠制备抗血清的优缺点。主要优点是实验所用的自交系小鼠很易大量饲养。缺点是从每只鼠身上只能获得很少量(1毫升或更少)的血浆,而且不能象在兔子身上那样有效地产生抗体。这是用芜菁黄花叶病毒(Turnip yellowmosaic virus)分别免疫鼠、兔进行比较得出的结论。但是应该指出,一只鼠只要用10—100微克病毒免疫就能制备出滴度为1/256  相似文献   
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