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1.
稀土钕制剂(RE-33,RE-41)的 LD_(50)如及经皮肤给药对心血管系统、造血功能和肝、肾功能影响的实验结果表明:RE-33的毒性小于RE-41。腹腔给药的LD_(50)分别比口服给药的 LD_(50)小4或3.5倍,提示稀土钕口服吸收并不完全。经皮肤给药的亚急性毒性试验结果表明:皮肤不论有无破损,对心血管系统、造血功能和肝、肾功能的影响与对照组相比,均无显著性差异(P>0.05),提示临床使用稀土钕作为外用药是安全的。实验还证明稀土钕制剂对感染性炎症有抗菌消炎作用。  相似文献   

2.
对热轧Nicalon SiC纤维/LD_2铝合金复合材料的显微组织进行了研究。文中对几种不同热轧工艺下制备的SiC/LD_2复合材料进行了金相显微镜、扫描电镜及透射电子显微镜分析和比较。测定了SiC/LD_2预制丝、热轧SiC/LD_2板材中的孔洞体积分数。结果表明,热轧SiC/LD_2板材中的孔洞含量远小于SiC/LD_2预制丝中的孔洞含量。利用电子探针分析技术分别对预制丝和热轧板材中纤维与基体之间界面附近的成份进行了分析,发现在热轧板材的界面附近出现了Mg元素富集。经研究得出:只要热轧工艺参数选择适当,就可以制备出结合良好的SiC/LD_2复合材料。  相似文献   

3.
本文对小白鼠口服云芝多糖制剂,按简化机率单位法,求得LD_(50)为11450±1190.8毫克/公斤体重,腹腔给药是1965±582.3毫克/公斤体重。亚急性毒性试验共设三组:最低致死剂量6850毫克/公斤体重,LD_(50)的1/10剂量1427毫克/公斤体重,LD50的1/20剂量572.2毫克/公斤体重。口服投药,隔天一次,25天内的小鼠生长率、血象、嚣官系数、主重器官病理切片、血清谷丙转氨酶、血中N.P.N,未出现明显差异。  相似文献   

4.
为了研究用气相色谱保留指数(Ⅰ)估算饱和脂肪酸酯类化合物的活性参数,为活性参数的烦琐测定,寻找简单的预测方法,对饱和脂肪酸酯类化合物的LD_(50)、LC_(50)与Ⅰ值的相关关系进行了研究。分别建立了用Ⅰ值估算饱和脂肪酸酯类化合物对大鼠LD_(50)和蝌蚪LC_(50)的一元线性回归方程。大鼠LD_(50)、蝌蚪LC_(50)与不同极性固定相上Ⅰ值的相关系数均值分别为0.914和0.990,均属显著相关(P0.05),回归标准误差均值分别为0.150 1和0.082 2,估算相对百分误差分别为7.68%和9.00%,且估算方程的相关性基本不受受试物种和固定相极性影响。  相似文献   

5.
红丝线草对哇巴因所致豚鼠心律失常及LD100的影响   总被引:1,自引:0,他引:1  
本研究主要探讨红丝线草的醇提水转溶物(简称01—w)对哇巴因致豚鼠心律失常和LD_(100)的影响。给药组采用三种不同浓度的01—w并分别与0.0125%的哇巴因同速(0.034ml/min)经豚鼠双侧颈外静脉灌注,对照组单用哇巴因,其浓度及灌注速度同给药组。实验结果表明:0.2g(生药)/ml组能显著提高哇巴因致豚鼠心律失常和LD_(10)的剂量(P<0.01),其它剂量组虽略能提高哇巴因致豚鼠心律失常及LD_(100)的剂量,但无统计学显著性。关于ol—w对抗强心甙毒性作用的机制正在深入研究中,可能与它的心肌保护作用有关。  相似文献   

6.
用Schauder不动点定理, 研究二阶迭代微分系统满足边界条件x(a)=y(a)=a, x(b)=y(b)=b或x(a)=y(a)=b, x(b)=y(b)=a时解的存在唯一性, 其中x[2](t)=x(x(t)).  相似文献   

7.
本实验观察生脉注射液对豚鼠Ouabain LD_(100)、致室性纤维颤动、室性心动过速剂量的影响。预先给生脉注射液0.1ml/100g体重Ⅳ(相当于生药0.0415g),5分钟后静脉恒速灌注0.025%Ouabajn,测得Ouabain LD_(100)剂量为0.4mg/kg体重(P<0.01),致室颤剂量为0.29mg/kg体重(P<0.01),致室性心动过速剂量为0.28mg/kg体重(P<0.01)。预先给单方五味子和人参根提取液各为20mg/100g体重(生药)Ⅳ,其Ouabain LD_(100)为0.43mg/kg(P<0.01)和0.34mg/kg(P<0.05)。生脉注射液、五味子提取液、人参根提取液对豚鼠Ouabain LD_(100)剂量都有增加作用,与对照组比较有非常显著和显著意义。生脉注射液还增加Ouabain致室颤和室性心动过速剂量,与对照组比较有非常显著的意义。结果提示,生脉注射液对强心甙的心脏毒性有保护作用。  相似文献   

8.
高活力饲用复合酶制剂的制备   总被引:3,自引:0,他引:3  
以粮油加工副产品为原料,经黑曲霉、米曲霉混合固态发酵,制备了有较高酶活和较全酶系的饲用复合酶制剂.发酵物料中m(麸皮):m(豆粕)=4:6,m(水):m(干料)=0.8:1,w(Zn^2 )=0.2%和w(Mg^2 )=0.02%能提高蛋白酶的活力,45℃烘干发酵料,各种酶活损失最小.  相似文献   

9.
在边值条件y(0)=y(1)=y″(0)=y″(1)=y(4)(0)=y(4)(1)=0或y(0)=y′(1)=y″(0)=y (1)=y(4)(0)=y(5)(1)=0下,研究方程d6y/dx6 h(x)f(y(x))=0的多个正解的存在性,在假定f满足在无穷远处超线性而在零点次线性的条件下获得至少有两个正解的结果.  相似文献   

10.
利用正交实验设计方法对复合水泥中各组分对强度的影响进行了研究,结果表明,在适当配比条件下,复合水泥的强度高于硅酸盐水泥型水泥,最佳配比范围为:w(石灰)=21%~24%;m(钢渣)∶m(粉煤灰)=10∶10~14∶14;w(沸石)=8%~12%;w(石膏)=4%~6%;w(矿渣)=15%~19%  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.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
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   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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