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51.
对早熟苹果辽伏喷布40%水胺硫磷1000倍液。喷后27d,果皮及果肉中残留量分别降至0.182mg·1~(-1)和0.028mg·1~(-1)。果皮中水胺硫磷残留含量一直呈下降趋势,但果肉中水胺硫磷含量在喷后前7d却在增加,第7天之后才呈下降。经对果皮及果肉中水胺硫磷含量的差比分析认为,果肉中水胺硫磷含量在喷后前7d增加,是果皮中农药向果肉中渗透大于果肉中农药消解所致。  相似文献   
52.
在牧草生长季节(5~9月)对小哨牧场放牧演替形成的5个草地型草地的牧草进行生长速率、牧草产量及养分的逐月观测,生长速率测定显示,白三叶+东非狼尾草和东非狼尾草+非洲狗尾草两个草地型草地均出现两个生长峰值,分别在6月和9月,其余3个草地型草地只有一个生长高峰。干物质产量和牧草养分测定结果表明,白三叶+东非狼尾草和白三叶+非洲狗尾草+画眉草两种草地型草地表现最好,可以在气候环境条件类似的地区推广种植利用;白三叶+画眉草和白三叶+非洲狗尾草两种草地型草地表现优良,可以在草地改良中,根据当地实际情况选择性地加以种植;东非狼尾草+非洲狗尾草型草地表现较差,不提倡种植。  相似文献   
53.
AIM: To investigate the contribution of angiotensin-converting enzyme inhibitor (ACEI) to the regulation of calpain system in infarcted myocardium. METHODS: Rat myocardial infarction (MI) model was established by permanent ligation of the left coronary artery. The treatment with the ACEI inhibitor rampril (1 mg·kg-1·d-1) was started 7 days prior to surgery. On day 1, 3, 7 and 14 after MI, protein levels of calpainⅠ, Ⅱ and calpastatin were determined in left ventricular free wall (LVFW), interventricular septum (IS) and right ventricule. RESULTS: CalpainⅠprotein level was increased in IS 14 d post MI, whereas the protein level of calpainⅡ was maximally increased in LVFW 3 d post MI. Rampril decreased protein up-regulation of calpainⅠ and Ⅱ, and reduced infarct size and interstitial fibrosis. Calpastatin protein expression was not affected by ACEI. CONCLUSIONS: CalpainⅠ is involved in cardiac remodelling in the late and calpainⅡ contributes to cardiac tissue damage in the early phase of MI. The heart protective effect of ACEI may be related to the inhibition of calpain system in the pathogenesis of myocardial infarction.  相似文献   
54.
浅谈蛋鸡开产体重对生产性能的影响   总被引:3,自引:0,他引:3  
吴忻 《中国家禽》2005,27(15):44-45
1、产蛋高峰短而低的问题。当养殖户遇到产蛋高峰不高或高峰上去后,又很快下降的问题时,往往将问题归咎到种鸡或饲料上,其实除了上面的问题外,还有一个重要的问题被忽视,这就是开产前的体重问题。根据国外各个品种的饲养要求,正常的鸡群在6周龄平均体重应达到标准上限或超标10%,均匀度达到90%以上;12周龄平均体重达标即可,均匀度应在85%以上;18周龄平均体重应达标或超标,均匀度达到80%以上。  相似文献   
55.
为了保持牛奶的新鲜程度,防止牛奶变酸和细菌数升高,各个规模牛场和收奶站均配备了牛奶冷却设备,同时还需要通过锅炉或电加热等方式生产大量的热水来清洗设备。利用锅炉或电加热生产热水不但浪费了大量的财力、物力和人力,还造成了环境污染。现介绍一种不额外消耗能源解决热水供应的方法,供大家参考。1原理冷冻机在制冷的同时,产生大于制冷量的热量。压缩机高压出来的温度一般超过90℃以上,这部分热量一般经过风冷的方式通过散热器散发到室外。特别是夏天,气温较高,散热器散热效率较低,需要浪费大量的冷却水冷却,即使这样,有时温度还是降不…  相似文献   
56.
鸡传染性腔上囊病病毒VP2基因在昆虫细胞中的表达   总被引:4,自引:0,他引:4  
为了深入研究鸡传染性腔上囊病病毒(IBDV)VP2基因的结构和功能,利用Bac-to-Bac系统研制出含有VP2基因的重组杆状病毒rBac-VP2,将rBac-VP2感染Sf9细胞,并用抗IBDV VP2特异性单克隆抗体经间接免疫荧光试验检测,证实感染重组病毒Sf9细胞能高效表达IBDV VP2基因产物;Western-blotting分析结果表明,VP2基因表达产物的分子质量约为40 ku.  相似文献   
57.
The morphological features of blood and milk neutrophils from peak lactating goats were compared using light microscopy, scanning electron microscopy and flow cytometry in order to investigate the cytological changes of neutrophils after migration into the mammary gland. The kinetics of reactive oxygen intermediates (ROI) generation and gelatinase release of blood and milk neutrophils, with or without stimulation of phorbol 12-myristate, 13-acetate ester (PMA), were used to characterize their responses to inflammatory stimuli. Neutrophils isolated from goat milk were highly segmented and contained multi-lobed nuclei. Ultrastructurally, milk neutrophils were more ruffled on the surface compared to blood neutrophils. Approximately 30% of milk neutrophils were undergoing cell death, either necrosis or apoptosis, in contrast to 8% of blood neutrophils. The ROI production of activated milk neutrophils peaked earlier than blood neutrophils, but the duration and the intensity were much less. Neutrophils from both sources augmented the release of gelatinase in response to PMA (1 ng/mL). However, the amount of gelatinase released from milk neutrophils was lower (P < 0.05) than that of blood neutrophils. In summary, more neutrophils become apoptotic and necrotic in the mammary gland, presumably due to spontaneous aging, the process of diapedesis, and the interaction with milk components. Milk neutrophils have impaired functionalities in comparison with blood neutrophils. The information is relevant when studying mammary gland immunity and related diseases, such as mastitis.  相似文献   
58.
番鸭在南京地区进行冬、夏两批饲养,均有较强的适应性。试验结果表明:冬、夏两 批饲养的番鸭只平均重量差异不显著(P>0.05)。夏季与冬季的料重比分别为1:2.62和1: 3.07,冬季饲养的鸭子饲料利用率低,料重比大于夏季。冬季在塑料大棚中饲养番鸭精饲料减 少1/3,添加青粗饲料能达到同样的增重效果。温度与增重无相关关系,相对湿度与番鸭的增 重呈负相关(P<0.01)。鸭舍内平均温度在11.05℃-30.93℃之间,相对湿度在76.28%以 下,番鸭能正常生长发育。环境温度在9.8℃以下,番鸭的生长发育受阻,饲料利用率降低。相 对湿度在77%以上,其增重受到影响。特别在低温高湿的环境中,严重地影响番鸭的生长。在 相同的饲养期内,周平均温度9.8℃,平均相对湿度91%,番鸭周平均增重22 g,周平均温度 27.42℃,平均相对湿度71.29%,番鸭周平均增重355 g,相差333 g(P<0.01)。  相似文献   
59.
AIM:To investigate the effects of Liucha extract on the growth of tumor cells in vitro and its possible mechanism.METHODS:The capability of colony forming of human leukemia K562 cell in vitro and the cells metabolism were studied by semi-solid agar culture and MTT staining. Then , the changes in morphology in the tumor cells were examined using electronic microscope.RESULTS:Semi-solid agar culture and MTT colorimetric analysis showed that Liucha extrats could significantly inhibit the growth of the tumor cells and their capability of colony forming. Also,under the electronic microscope,it was found that the tumor K562 cell had a narrower perinuclear space,condensation of chromatin and an enlarged mitochondria , in which the cristase disappeared.CONCLUSION:The extract from Liucha possesses an inhibitory effect on K562 cell growth in vitro through affecting the metabolism of the tumor cells.  相似文献   
60.
AIM and METHODS:To analysis the factor that involved in renal carcinogenesis, we used the bait gene AK001518 to screen GenBank. To understand the relationship between cell cycle related gene(CCRG) and p15, we did RT-PCR and Northern Blot experiments. Then we examined CCRG expression level in renal carcinogenesis. RESULTS:Gained a function unknown gene CCRG that was 67% a mino acid identical with the gene AK001518 that was regulated by p15. It was shown that the CCRG mRNA was dramatically decreased when p15 gene was over-expressed. CCRG expression level was much higher in tumor tissues and cells than normal tissues and cells. CONCLUSION:The novel gene CCRG expressed highly in the renal carcinoma, which might play a significant role in the renal carcinogenesis.  相似文献   
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