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401.
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利用柔性垫网接触式间歇干燥单板的方法对毛白杨单板进行干燥。中间试验结果表明,此方法提高了单板干燥质量,生产工艺可行。 相似文献
403.
通过对SLHY0.125型混合机配套设备的简化、优化设计,使之能够适应中、小型饲料加工厂的现实生产条件。 相似文献
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Xiaodong Yang Weilong Wang Xufeng Su Siyu Ren Qiying Ran Jianlong Wang Jianhong Cao 《Growth and change》2023,54(1):101-134
Under the system of political centralization and economic decentralization, the expanding scale of land finance and the increasingly severe environmental pressure have jointly become crucial features of China's urban development. Therefore, it is of great practical significance to study the intrinsic mechanism of land finance on haze pollution for China's economy to achieve kinetic energy transformation and green development. This paper empirically analyzes the impact of land finance on haze pollution using a dynamic spatial Durbin model based on panel data of 269 prefecture-level cities in China from 2004 to 2017. The statistical results show that haze pollution has a significant “snowball effect” and space spillover effect. Land finance has a significant positive effect on haze pollution. Land transfer both by agreement and by bid invitation, auction, and listing have significant positive effect on haze pollution. However, the promoting effect of land transfer by agreement on haze pollution is significantly higher than that of land sale by bid invitation, auction, and listing. Furthermore, regional heterogeneity implies that for cities in the eastern region, land finance is conducive to alleviating haze pollution. In contrast, for cities in the central and western regions, land finance significantly promotes haze pollution. 相似文献
406.
Xiongfei Wu Chenggang Li Guozhen Xing Xinming Qi Jin Ren 《Journal of toxicologic pathology》2013,26(4):385-392
Cyp2e1 plays an important role in chemically induced hepatocarcinogenesis. Resveratrol (REV) is known to prevent diethylnitrosamine (DEN)-induced hepatocarcinogenesis, but its effects on this process induced by DEN and 2-acetylaminofluorene (2-AAF) and the role of Cyp2e1 remain unclear. In this study, glutathione S-transferase placental form (GST-P)-positive foci were used as a marker of hepatocarcinogenesis. REV or diallyl disulfide (DADS, an inhibitor of Cyp2e1) significantly reduced both the area and number of GST-P-positive foci induced by DEN and 2-AAF. Treatment with REV or DADS also markedly decreased the expression of Cyp2e1 in the rat liver. By immunohistochemical staining of serial liver sections, we found that the expression of Cyp2e1 in GST-P-positive foci showed three distinct patterns: decreased in GST-P foci, increased in GST-P foci when compared with surrounding liver tissue and mixed type. The number of GST-P foci with increased Cyp2e1 expression was greater than the number of GST-P foci with decreased Cyp2e1. Protein levels of GST-P and Cyp2e1 were also higher in foci compared with surrounding liver tissue. REV or DADS significantly reduced the expression of GST-P and Cyp2e1 in both foci and surrounding liver tissue. Taken together, these results suggested that REV has a significant inhibitory effect on chemically induced hepatocarcinogenesis, which may be attributed to downregulation of Cyp2e1. 相似文献
407.
耐高温植酸酶用于颗粒饲料对肉鸡生产性能及钙、磷利用率的影响 总被引:3,自引:0,他引:3
试验旨在研究肉仔鸡低磷日粮颗粒饲料中添加耐高温植酸酶对肉鸡生产性能及钙、磷利用率的影响。选取1日龄AA+肉仔鸡,随机分为6个处理,分别饲喂处理1(正对照,正常磷水平)、处理2(负对照,低于正常磷水平)、处理3(负对照+500U植酸酶)、处理4(高磷替代+500U植酸酶)、处理5(负对照+1000U植酸酶)和处理6(高磷替代+1000U植酸酶)试验日粮。试验结果表明:在制粒饲料中添加耐高温植酸酶是可行的。在相同有效磷水平下,随着植酸酶添加水平的提高,出栏体重有增加的趋势;在相同植酸酶添加量的条件下,随着有效磷替代水平的提高,出栏体重有降低的趋势。添加植酸酶有增加胫骨灰分和磷含量的趋势。在正常替代水平下,植酸酶的添加量以500~1000U/kg为宜。在本试验条件下,日粮添加500~1000U/kg植酸酶的情况下,进行磷酸氢钙的高水平替代也是可行的。 相似文献
408.
Xiaohui Zhang Shangzhong Xu Xue Gao Hongyan Ren Jinbao Chen 《Frontiers of Agriculture in China》2008,2(4):493-497
The cDNA of cattle Smad4 gene was cloned by RT-PCR, 3′ RACE and 5’t RACE and got a 3503-bp full-long cDNA sequence. The cloned cattle Smad4 cDNA sequence had been send to GenBank and got an accession number: DQ494856. Cattle Smad4 gene consists of 12 exons and codes 553 amino acids. Cattle Smad4 cDNA shares 99%, 96%, 95%, 91% and 91% similarity in nucleic acid sequences, and 99%, 98%, 98%, 99% and 98% similarity in
amino acid sequences with sheep, pig, human, rat and mouse, respectively. Smad4 cDNA was found in the testes, pancreas, liver, small intestine, ovary, lymph, cardiac muscle, skeleton muscle and thymus
gland, which indicated that Smad4 was broadly expressed in cattle.
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Translated from Acta Veterinaria et Zootechnica Sinica, 2007, 38(4): 321–325 [译自: 畜牧兽医学报] 相似文献
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