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研究肉仔鸡成长过程中行为变化对产热量的影响 ,将 2日龄肉仔鸡 36只分为自由摄食、 50 %摄食和绝食 3组进行观测。立位行为集中在明期 ,特别是摄食 30min前后 ,暗期几乎没有出现立体行为。 2日龄时 ,每天约有 70 0min是立位的 ,其后 ,随着日龄的增加而减少。在自由采食区 ,公雏比母雏摄食时间长。 50 %摄食区较自由采食区的摄食时间少。在绝食区 ,随着日龄的增加 ,公母的立位时间呈现减少倾向。 2 1日龄之前随着日龄的增加其摄食时间也增加 ,其后呈现相反倾向。产热 (HP ,kJ/kg0 75)与摄食时间有相同倾向。在 2 1日龄前公雏的HP比母雏低 ,2 1日龄后母雏比公雏低。 1天中各个区的HP活动规律是摄食后 1h内最高 ,暗期降低 ;限制摄食量后 ,HP降低 ,明期和暗期的HP差也随之减小 相似文献
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AIM: To explore the variation of blood biochemistry and arterial blood gas of patients with systemic inflammatory response syndrome (SIRS) in the early time after trauma and improve the diagnosis and first aid. METHODS: Eighty-eight patients with trauma from August 2003 to February 2004 were divided into two groups by their AIS-ISS90 score. The data of temperature, pulse, respiratory rate, white blood cell counts, Hb, blood glucose and arterial blood gas (PaO2, PaCO2, HCO3-, AG) were collected and compared with each group by statistic methods. RESULTS: Of the 88 patients, 49 underwent SIRS, 12 in light trauma group (ISS≥16) and 37 in severe trauma group (ISS<16). Compared with light trauma group, the data of pulse, respiratory rate, white blood cell counts, blood glucose, AG and rate of SIRS of severe trauma group were higher, PaO2 and HCO3- were lower and the cases of PaCO2>45 mmHg or <35 mmHg were more (P<0.01). The data of temperature and Hb had not significant difference between two groups (P>0.05). 13 patients had MODS in severe trauma group and 2 died while none had MODS or died in light trauma group. CONCLUSION: Application of AIS-ISS90 and SIRS-related blood biochemistry and arterial blood gas is beneficial for the diagnosis and treatment of patients in the early time after trauma. 相似文献
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AIM: To investigate inhibition of K562 cell growth by antisense drug targeted VEGF mRNA. METHODS: X7, 20-mer antisense sequences were selected, synthesized and modified with phosphorothioate. The drug was transfected into K562 cells in the present of lipofection. Cell growth was assayed by trypan blue dye exclusion assay and MTT. The level of VEGF protein in the media was determined by ELISA. The morphology of apoptotic cells were observed by Giemsa staining, and the propotion of apoptotic cells was detected by flow cytometry. RESULTS: The antisense drug inhibited growth of K562 and downregulated expression of VEGF protein significantly, compared with Scrambed control group and showed dose-dependent relation. Signs of apoptosis of K562 cells were not observed. CONCLUSION: Inhibition of K562 cell proliferation, but not cells apoptosis induction is the mechanism of inhibing growth of K562 cells by antisense drug targeted VEGF mRNA. At same time, VEGF has function of promoting K562 cell proliferation, and VEGF mRNA may be a new target attached by drugs. 相似文献
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安婀珍蝶Actinote anteas(Doubleday & Hewitson)是薇甘菊的天敌,取食薇甘菊Mikania micrantha Kunth.的叶片,能有效的控制薇甘菊的蔓延和生长。在广州市和深圳龙岗进行的观察表明,在实验室条件下,安婀珍蝶一年生长3代~4代。世代平均历期为112.44±1.18天;卵期平均为11.44±1.18天;幼虫期平均为82.54±4.05天;蛹期平均为12.98±1.31天;成虫期平均为7.33±0.80天。本文还记述了该蝶各虫态的形态特征、生活习性及其天敌等。 相似文献
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引诱剂在综合防治桔小实蝇作用中的评估 总被引:5,自引:1,他引:5
以使用引诱剂为主 ,坚持在杨桃园挂引诱笼 2 - 3年后 ,大量降低田间桔小实蝇BactroceradorsalisHendel雄虫数量和卵的受精率 ,配合其它的综防措施 ,防效逐年提高。三个综防点试验实践表明 :杨桃每果虫口数 ,卵孵化率及受害果率大大降低 ,防效达 92 5%。对桔小实蝇的防治初见成效。 相似文献
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AIM: To examine the effects of inhibition of Kupffer cell and splenectomy on intestinal endotoxemia and hepatic injury. METHODS: The hepatic injury model was established by treatment with thioacetamide (TAA). At the same time, inhibition of Kupffer cells by intravenous GdCl3 and splenectomy were performed. Serum alanine aminotransferase (ALT), TNF-α, endotoxin content and phagocytic index were observed. RESULTS: In the TAA+GdCl3 group, and TAA+splenectomy group, the endotoxin content was significently higher than that in normal and TAA group (P<0.05). The plasma TNF-α, ALT and total bilirubin were significantly lower than those in TAA group (P<0.05). CONCLUSION: Inhibition of Kupffer cells and splenectomy increase plasma endotoxin level, but decreases the plasma TNF-α levels and alleviates the hepatic injury induced by TAA. 相似文献
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秀丽纤杆线虫 (Caenorhabditis elegans)是一种模式线虫 ,目前广泛应用于寄生性线虫基因的功能研究 ,并且还被用于捻转血矛线虫等寄生性线虫疫苗侯选抗原基因的表达和耐药性产生机制方面的研究 相似文献