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81.
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Secretion of concentrated salt solutions from the nasal region was observed in several terrestrial birds and reptiles. In the secreted fluid potassium usually exceeded sodium concentrations, with chloride and bicarbonate as the major anions. It is suggested that the extrarenal excretion of salts is related to the reabsorption of water in the cloaca, that it is necessary for the production of urine with a particularly low water content, and perhaps was prerequisite for the evolution of efficient cloacal water conservation. 相似文献
83.
ABSTRACT Owing to its competitive labor costs, its open‐market policy, and a substantial amount of capital investments, China has become a global manufacturing pole and an export‐based economy replicating the conventional Asian model but on a much wider scale. This is creating acute competition on other Asian export‐based economies such as Korea that have to adapt to the “China effect.” Consequently, many Korean manufacturing companies have repositioned their capital and equipment in China to enlarge their market potential as well as to reduce their production costs. Because Korea is adjacent to China—both are sharing the Yellow Sea Rim—this shift is creating a unique geographical dimension with a high level of functional integration of Sino‐Korean manufacturing supply chains. This transition has also brought substantial changes in the regional logistic network by organizing new flows of raw materials, parts, and final products, most of them along the Yellow Sea Rim. New logistic flows have given substantial influences on regional port competition by creating diverse links. These changes are bringing a reorientation of the regional maritime industry and of the port system. 相似文献
84.
(1)稻田轮种棉花期间,土壤有机质含量有减低的趋势,但土壤代换性盐基总量及速效磷的合量均增高。轮种水稻期间,土壤有机质又有增加的趋向,而代换性盐基总量及速效磷则渐次减低。此外,土壤中铵态氮则有增多的趋势。(2)稻棉轮种能增强水稻的生长势,提高水稻的产量。根据对比试验及统计资料,一般比连种区增产9%左右。(3)稻田轮种棉花后,冬作绿肥生长良好, 鲜草产量比一般连种稻田增加70%以上。(4)在保证增产的前提下,轮种区的水稻基肥用量,一般可比连作稻区节省40%左右,而轮种区的绿肥产量又能增加,因此可自轮种田内割出60%的绿肥鲜草,作为其他稻田的基肥,而达到全面增产的目的,这在目前肥料普遍不足的情况下有其重要意义。 相似文献
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86.
Jin HUR Seong Kug EO Sang-Youel PARK Yoonyoung CHOI John Hwa LEE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1693-1696
Salmonella Typhimurium strain expressing the Actinobacillus
pleuropneumoniae antigens, ApxIA, ApxIIA, ApxIIIA and OmpA, was previously
constructed as a vaccine candidate for porcine pleuropneumonia. This strain was a live
attenuated (∆lon∆cpxR∆asd)Salmonella as a delivery host
and contained a vector containing asd. An immunological study of
lymphocyte proliferation, T-lymphocyte subsets and cytokines in the splenocytes of a mouse
model was carried out after stimulation with the candidate Salmonella
Typhimurium by intranasal inoculation. The splenic lymphocyte proliferation and the levels
of IL-4, IL-6 and IL-12 of the inoculated mice were significantly increased, and the T-
and B-cell populations were also elevated. Collectively, the candidate may efficiently
induce the Th1- and Th2-type immune responses. 相似文献
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88.
华南热带区及亚热带区的成土作用,直到现在还有许多没有解决的问题,例如,现代生物气候条件下土壤的发育方向;红壤和黄壤的关系及其基本特性的差异;红壤中校普遍存在的鐵子、鐵盤及网状斑纹的成因等,都有不少的争论[1-8]。 相似文献
89.
Son Hai VU Bomin KIM Alisha Wehdnesday Bernardo REYES Tran Xuan Ngoc HUY John Hwa LEE Suk KIM Hyun-Jin KIM 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(3):482
To better understanding Brucella abortus infection, serum metabolites of B. abortus-infected and -uninfected mice were analyzed and twenty-one metabolites were tentatively identified at 3 and 14 days post-infection (d.p.i.). Level of most lysophosphatidylcholines (LPCs) was found to increase in infected mice at 3 d.p.i., while it was decreased at 14 d.p.i. as compared to uninfected mice. In contrast, acylcarnitines were initially reduced at 3 d.p.i then elevated after two-weeks of infection, while hydroxysanthine was increased at 14 d.p.i. in infected mice. Our findings suggest that the significant changes in LPCs and other identified metabolites may serve as potential biomarkers in acute phase of B. abortus infection. 相似文献
90.