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1.
采用自选单胞藻代替小球藻调节育苗池水质和对轮虫,卤虫营养强化;控制水温15-20℃,光照4400Lux以上,换水20-30%等培养轮虫;以及按卤虫总量的2.5-3.0%的浓鱼油胶丸营养强化卤虫等技术措施,使仔稚幼鱼从0龄至47日龄存活率达到64.80%以上,47日龄至90日龄存活率达到80.71%。  相似文献   

2.
2000-2001年研究了化学物A、B、C、D及其混配剂对白肋烟烟碱合成、烟叶产量、产值及评吸质量的影响,结果表明:化学物A、B及化学物B+C能显著降低白肋烟烟碱含量,改善评吸质量;与对照相比,上部叶烟碱下降0.89-3.42个百分点,降幅达12.95%-49.785;中部叶烟碱下降1.77-3.81个百分点,降幅达24.25%-52.19%;化学物A+C及化学物C单用能降碱,但幅度不大。所有处理对烟叶产值、产量无明显不利影响。通过这一研究,基本确定了降低白肋烟烟碱含量、提高其可用性的有效化学调控技术。  相似文献   

3.
目的 比较3种方法治疗高能量Pilon骨折的临床效果。方法自1995年~2004年共收治高能量Pilon骨折患者95例,均属Ruedi和AllgouerⅡ,Ⅲ型。按治疗方法不同分为3组:即采用AO苜蓿叶形钢板内固定32例为A组;有限内固定结合“T”形超关节外固定架治疗30例为B组;短期外固定架固定后改用钢板内固定33例(即两阶段法)为C组。结果 经10个月-8年的随访(平均2.4年),按Teeny和Wiss评分系统,A组临床疗效优良率为65.63%,并发症发生率为26.5%;B组临床疗效优良率为60.00%,并发症发生率为30.5%;C组临床疗效优良率为84.85%,并发症发生率为22.5%.结论三种方法可用于高能量Pilon骨折的治疗,其中两阶段治疗法疗效较佳。  相似文献   

4.
目的:评价帕落西汀文拉法辛西酞普兰治疗抑郁症的成本、效果。方法:90例门诊抑郁症患者随即分为A.B.C组三组,分为帕落西汀组,文拉法辛组,西酞普兰组,并进行成本一效果分析。结果:A,B,C组成本分别为7454.70,8086.40,9970.80元。显效率分别为90%,83%,80%。成本效果比为82.83,97.43,124.64,不良反映率分别为10%,17%,20%。结论为A组药效最佳。  相似文献   

5.
异丙酚及米索前列醇应用于人流术的临床观察   总被引:3,自引:0,他引:3  
目的:探讨异丙酚及米索前列醇对人流术并发症的影响,旨在寻找一种安全、有效的无痛人工流产术。方法:按知情自愿原则将429名孕妇分为3组:异丙酚麻醉人流组176例(A组)、异丙酚麻醉 米索前列醇人流组173例(B组)、普通人流组为对照80例(C组)。比较3组孕妇术中出血量、手术时间、术后阴道流血时间、宫颈松弛度、子宫收缩及人流并发症的发生情况等。结果:A组的术中出血量明显多于B组和C组,差异有统计学意义(P=0);B组与C组之间的差别无统计学意义(P=0.59)。宫颈松弛度,B组宫颈松弛度明显高于A组及C组,术中宫颈松弛,能直接通过7号扩宫器的孕妇在B组占35.9%(62/173),A组占5.6%(10/176),C组占8.8%(7/80)。术后阴道流血大于7d的发生率:A组28.4%(50/176),高于B组的18.4%(32/173)及C组的12.5%(10/80)。术中子宫不收缩,官腔较术前增大的发生率:A组为35.80A,(63/176),而B组为0(0/173),C组为0(0/80)。其余项目在3组无明显差别。结论:异丙酚麻醉抑制子宫收缩,因而增加术中出血量。术前加服米索前列醇促进子宫收缩,能有效减少术中出血。  相似文献   

6.
通过等标污染负荷的评价方法,按评价流域内污染物和污染源的等标污染负荷比从大到小排列,将累计百分比大于80%左右的污染物和污染源确定为开孔河流域的主要污染物和污染源。  相似文献   

7.
矿物中的包裹体是成岩成矿流体(含气液的流体或硅酸岩熔融体)在矿物结晶生长过程中,被包裹在矿物或晶格缺陷或穴窝中的、至今尚在主矿物中封存并与主矿物有着相的界限的那部分物质。矿物中的包裹体按物理状态分主要分为以下两类:Ⅰ、流体包裹体,又可根据组成的不同分为七个亚类:ⅠA.纯液体包裹体;ⅠB.纯气体包裹体;ⅠC.液体包裹体;ⅠD.气体包裹体;ⅠE.含子矿物包裹体;ⅠF.含液体CO2包裹体;ⅠG.油气包裹体;Ⅱ、熔融包裹体,又可根据相态特征分为三个亚类:ⅡA.非晶质熔融包裹体;ⅡB.结晶质熔融包裹体;ⅡC.晶质一流体熔融包裹体。本文从综述的角度对矿物包裹体的定义、分类、研究方法及现状进行了详细的阐述,指出其新的研究方法和应用前景。  相似文献   

8.
从科睿唯安InCites数据库中抽取人工智能文献数据,将被引次数累计百分比处于前10%的文献的作者界定为基础研究人才,以1‰、1%、10%为标线将其划分为A、B、C 3个层次,构建基础研究人才指数;比较中国与主要发达国家人工智能基础研究人才的发展趋势,分析A、B、C层人才之间的相互关系,运用回归分析方法,探讨中国人工智...  相似文献   

9.
三种不同内固定方法治疗髌骨骨折及对膝关节功能的影响   总被引:2,自引:0,他引:2  
目的评价三种髌骨骨折内固定治疗效果及对膝关节功能的影响。方法手术治疗髌骨骨折120例,其中A组38例采用粗丝线或可吸收粗线环形缝合固定,B组44例采用A0改良张力带固定,C组38例采用镍钛聚髌器(NTPC)固定。结果A、B、C三组膝关节活动度分别为71.05%、81.82%、89.47%;膝关节功能恢复优良率分别为84.21%、90.91%、97.37%。结论三种不同内固定方法可用于髌骨骨折的治疗,而后二种方法更佳,且缝合固定法由于不可避免的外固定,而在治疗近期可对膝关节造成一定的影响。  相似文献   

10.
在大量采集涠西南凹陷烃源岩和原油饱和烃色谱、色谱-质谱、碳同位素等资料基础上,对涠西南凹陷烃源岩特征进行分析,根据地球化学特征差异划分为A、B、C等3类烃源岩。系统分析原油有机地球化学特征差异性,对不同层系原油物性进行统计梳理,依据甾、萜烷、饱和烃组成等进行原油成因类型划分,将涠西南凹陷原油分为A、B1、B2、C1和C2等3大类5亚类。通过油源精细对比和原油空间分布特征分析,A类原油来源于A类源岩,主要分布在1号、2号和3号断裂附近及东南部的斜坡部位;B1和B2类原油来源于B类源岩,其中B1类原油主要分布在2号断裂附近,B2类原油主要在3号断裂附近;C1和C2类原油来源于C类源岩,C1类原油分布在与B1类原油相近的区域,C2类原油主要集中分布在2号断裂与3号断裂接近交互的部位。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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