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排序方式: 共有398条查询结果,搜索用时 15 毫秒
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作者于1983年开始将以葡萄糖—钠泵学说为理论的口服补液盐(ORS)技术引入我国畜牧兽医领域,经过几年的临床研究;先后在防治犊牛、猪、雏鸡和犬的腹泻脱水等获得86~98.7%的成功率。健康绵羊ORS液吸收实验和与静脉输液、口服蒸溜水吸收比较实验证明,ORS液的各种成分在服后2小时内,不仅能被胃肠粘膜吸收,极显著改善红细胞压积(P<0.01),而且初步观察到促水分吸收的葡萄糖—钠泵现象。 相似文献
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This paper introduces a method of solving the problem of leather cavity measurement in shoe CAD/CAM by industrial CT technology. Concentrating on peculiarity and requirement of leather cavity measurement, this paper presents a X-ray industrial CT system scheme, which not only satisfy the requirement of leather cavity measurement but also can achieve general industrial CT. measurement. The achievement on data collection system and motion control of stepping motor is emphasized. 相似文献
7.
The cavity induced by top-blow gas jets impinging on the bath surface is one of most important parameters, which has overwhelming influence on the rate of slag formation and metallurgical performance. Water model experiments are conducted through a 1/10 scaled-down top-blown convertor. Effects of lance height and gas flow rate on penetration behavior are studied, and also the influence mechanism of liquid surface tension on penetration depth is addressed based on the experiments and theory analysis. An energy utilization index (EUI) is defined to reflect how much the impinging kinetic energy of gas jets are transferred into bath for formation of cavity, and an improved model is proposed to predict penetration depth of jets. The results show that penetration depth increases with lowering lance height and increasing gas flow rate, and impact diameter increases with increasing lance height, but is little affected by gas flow rate. Influence of liquid surface tension on penetration depth is enhanced with increasing surface tension and penetration depth. The EUI increases with increasing lance height, and a function relationship of it with lance height is obtained based on the experiments. 相似文献
8.
定向井螺杆泵抽油杆柱力学分析及防磨损措施 总被引:2,自引:0,他引:2
由于定向井井身结构特殊,利用螺杆泵进行抽油时如不采取任何措施势必造成杆柱严重磨损甚至卡死。为消除这种现象降低杆管磨损,提出在造斜点处的抽油杆柱上安装导向器以及在杆体上合理布置扶正器的技术措施。建立抽油杆柱有限元模型,利用ANSYS有限元软件进行分析计算,从而给出扶正器及导向器的合理配置原则。现场应用效果表明该方法实用、合理。 相似文献
9.
Passive immunisation of fish against vibriosis, comparison of intraperitoneal, oral and immersion routes 总被引:2,自引:0,他引:2
M. Akhlaghi 《Aquaculture (Amsterdam, Netherlands)》1999,180(3-4):191-205
Passive immunisation of fish was conducted to determine whether anti-Vibrio anguillarum whole sera (AVA) and affinity-purified AVA raised in sheep, rabbits and rainbow trout (Oncorhynchus mykiss) were persistent when injected and orally administered into rainbow trout. These responses were compared with active immunisation by immersion in, and intraperitoneal (i.p.) injection with, formalin-killed V. anguillarum cells. Sheep and rabbit AVA were detected in rainbow trout sera for up to 70 days (half-life 21 days) after i.p. injection as determined by an enzyme-linked immunosorbent assay (ELISA). The relative percentage survival (RPS) of passively immunised rainbow trout challenged with virulent V. anguillarum after an injection was comparable to that of active immunisation by immersion after 1 month post-immunisation (p.i). Affinity-purified sheep and rabbit AVA exhibited the same protective potential as whole serum in rainbow trout. Rabbit and sheep immune sera diluted 1:8 and 1:50, respectively, provided equivalent protection as undiluted fish immune serum. An active immune response against passively acquired heterologous immunoglobulins was demonstrated by ELISA, with responses against sheep AVA being less than those against rabbit AVA. Rainbow trout given purified sheep AVA conjugated to LTB (the GM-1-binding subunit of Escherichia coli heat-labile toxin) and administered orally had an RPS of 37.5% at 15 days and 27% at 1 month p.i. In contrast, fish given sheep AVA conjugated to TraT (an internal membrane of E. coli) or in micellar form with Quil-A had RPSs of only 18.7 and 6.2%, respectively, after 15 days, and 13.3 and 0% after 1 month, respectively. The protection conferred by immune sera was shown to be due to the immunoglobulin component alone. Heat inactivation of the complement in sera had no effect on the potency of immune sera. 相似文献
10.
Seung-Taek Oh Oh-Jin Kwon Byoung-Chul Chun Jae-Whan Cho Jong-Shin Park 《Fibers and Polymers》2009,10(1):21-26
We produced a protein loaded, pH-sensitive alginate-bentonite hydrogel for wound dressings. Alginate is a nontoxic polysaccharide
with favorable pH-sensitive properties that make it useful for the intestinal delivery of protein drugs. However, the use
of alginate for drug delivery is limited by drug leaching and rapid dissolution of alginate at the higher pH, which may result
in lower entrapment efficiency and a burst in the release of entrapped protein drugs. To overcome these problems, we created
a novel cross-linked alginate-bentonite hydrogel by combining mineral-rich bentonite with the alginate matrix along with an
additive to ensure controlled release. We analyzed the gel in the drug loading process in an aqueous environment by looking
at the release profiles of a model protein drug (BSA) from the hydrogel at pH values of 4.5, 5.2 (skin area) and 7.4, 9.2
(wound area). The swelling ratio decreased with bentonite concentration, but did not fall below 6. The rate of drug release
was slowest at a pH value of 4.5 and fastest at a pH value of 9.2. The rate of drug release decreased with bentonite concentration.
The presence of bentonite prevents the rapid dissolution of alginate at the higher pH, ensuring the controlled release of
the entrapped drug. 相似文献