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Wilson JA Heath AC Stringfellow L Haack NA Clark AG 《New Zealand veterinary journal》1996,44(5):185-187
Four groups of five Romney lambs were treated by plunge dipping with one of four registered organophosphorus flystrike preventatives. Untreated lambs acted as controls. The sheep were challenged at weekly intervals with larval implants of organophosphate-susceptible and -resistant strains of Lucilia cuprina. All four treatments provided 19-21 weeks protection against susceptible larvae but chlorfenvinphos provided the longest protection (16-17 weeks), followed by propetamphos (15-16 weeks), dichlofenthion (10-13 weeks) and diazinon (9-13 weeks), against the resistant strain. 相似文献
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Two cats with chronic eosinophilic skin disease were investigated. The clinical investigation of the skin disease in one cat was limited and inflammatory bowel disease was diagnosed post mortem. A history of weight loss and a palpably thickened bowel in the second cat suggested concurrent gastrointestinal disease. Diagnosis of inflammatory bowel disease was confirmed on biopsy. Treatment with azathioprine and methylprednisolone acetate resolved the signs of gastrointestinal disease, the pruritus and 95% of the skin lesions. The concurrence of eosinophilic papulocrustous dermatitis and eosinophilic bowel disease raises the possibility of their being linked bv a common aetiology or pathophysiology. 相似文献
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Kaneps AG 《Science (New York, N.Y.)》1979,204(4390):297-301
Biostratigraphic analysis of seven piston cores from the southeastern Blake Plateau suggests that the upper Miocene to Recent sedimentary section at this location represents a history of deposition of calcareous ooze alternating with current-induced nondeposition or erosion. This record is primarily a result of long-term fluctuations in the velocity of the western boundary current or Gulf Stream, which sweeps the plateau. High-velocity phases of this current system, as signaled by hiatuses in the section, lie within the time limits 4.8 to 6.1, 3.9 to 4.4, 2.3 to 2.9, and 0 to 1.5 million years before present (B.P.). These time intervals are coeval with dated episodes of climatic decline and glaciation. The most intense acceleration of the Gulf Stream, as indicated by deep erosion of the Blake Plateau, occurred in the latest Miocene to earliest Pliocene (4.8 to 6.1 million years B.P.) in conjunction with a major expansion of the Antarctic ice cap. Subsequent accelerations of the Gulf Stream coincide with early Pliocene cooling in the Southern Hemisphere, worldwide expansion of high-altitude-high-latitude glaciers in the late Pliocene, and the classical glaciations of the Pleistocene. An additional, protracted increase in the average velocity of the Gulf Stream, which began in the late Miocene and culminated in the mid-Pliocene (about 3.8 million years B.P.), can be attributed to the gradual emergence of the Central American isthmus. 相似文献
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近两年水果获大丰收 ,价格一跌再跌 ,销售形势愈显严峻。困扰我们的“卖果难”话题 ,又一次摆到面前来。与此同时 ,在我国一些大城市的超市或水果市场的进口洋水果 ,不论是苹果、柑橘、梨、葡萄 ,还是猕猴桃、香蕉、芒果、布朗李等 ,不但比国产同类水果价格高出很多 ,而且卖得快。国产水果比洋水果到底差在哪里呢 ?除了品种、品质等因素外 ,还有一个易被大多数果品生产者和中间商忽略的环节 ,那就是采后处理。国外的水果多在采前 7天~ 10天 ,喷 1次杀菌剂 ,成熟采收 ,然后进行清洗、打蜡、分级和包装外运或入库。这就是洋水果光洁耐贮的秘… 相似文献
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菌类蔬菜 :指在各种作物秸秆等农业副产品上接入不同食用菌种后 ,生产出的各种鲜活食用菌产品。菌类产品 ,不施用化肥、农药 ,纯属绿色食品 ,其营养高、疗效好的食用价值 ,被国际上公认为健康食品 ,有关人士预言 ,未来的餐桌消费 ,将是“无菌不成食” ,市场前景极好。野生蔬菜 :营养丰富 ,具有一定药用价值 ;且远离工业污染 ,又不施用化肥、农药等 ,纯属天然食品 ,如蕨菜、荠菜、苦菜、刺儿菜、蒲公英、野苋菜、曲曲牙以及蒲菜等。花卉蔬菜 :鲜花内含蛋白质、淀粉、脂肪、氨基酸和微量元素等 ,经常食用 ,其保健作用明显 ,如韭菜花、梅花、桂… 相似文献
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Began G Sudharshan E Udaya Sankar K Appu Rao AG 《Journal of agricultural and food chemistry》1999,47(12):4992-4997
Curcumin [1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3, 5-dione], the main constituent of the rhizomes of the plant Curcume longa L. (turmeric), is a powerful antioxidant in both enzymatic and nonenzymatic systems. The interactions of curcumin with egg and soy phosphatidylcholine were followed by fluorescence spectroscopy. Curcumin had very weak fluorescence in aqueous system, which was enhanced in apolar environments. Curcumin emitted at 490 nm after being excited at 451 nm in phosphatidylcholine micelles. The equilibrium constants for the interaction of curcumin with egg and soy phosphatidylcholine were (3.26 +/- 0.2) x 10(5) and (2.64 +/- 0.2) x 10(5) M(-1), respectively. From the Scatchard plot of the fluorometric data, it was inferred that one molecule of curcumin could bind six molecules of phosphatidylcholine. The equilibrium constant for the phosphatidylcholine-curcumin interaction decreased with temperature, indicating the amphiphilic nature of curcumin. The DeltaG, DeltaH, and DeltaS values obtained for the interaction of egg phosphatidylcholine-curcumin were -7.8 +/- 0.3 kcal/mol, -9.6 +/- 0.4 kcal/mol, and -6.8 +/- 0.2 cal/mol/K, respectively. The fluorescence anisotropy measurements of curcumin with phosphatidylcholine suggested that the anisotropy of the curcumin molecule did not change in phosphatidylcholine. The interaction of divalent metal ions with phosphatidylcholine-curcumin in comparison with phosphatidylcholine-1-anilino-8-naphathalenesulfonic acid complex suggested the strong binding of curcumin to metal ions. 相似文献