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1.
采用喷雾法和注射法分别测定了速灭杀丁对中华稻蝗成虫的毒力,结果表明:胃毒LC50为2.68μg/ml,LC90为16.11μg/ml,毒力回归方程为y=4.2982+1.6416x,相关系数r=0.9686;注射毒性LC50为0.13μg/ml,LC90为0.86μg/ml,毒力回归方程为y=3.2447+1.5677x,相关系数r=0.9806。同时观察了注射药剂及蒸馏水对照24h,48h后细胞分裂各期染色体的形态特征,结果未发现有明显的染色体畸变现象。  相似文献   

2.
比较单硝酸异山梨酯两种片剂在正常人体内药物动力学及相对生物利用度。8名健康志愿自身交叉口服单剂量(20mg)单硝酸弃山梨酯片剂,用气相色谱--电子捕获检测法测定单硝酸异山梨酯经时过程的血药浓度,其数据用3p87程序拟合,求得对照品和研制样品片剂的药动学参数。对照品和研制样品片剂的药动学参数分别为:Ka(2.4±0.8)h^-1和(2.1±0.3)h^-1;t2/2β(7.0±0.7)h和(7.2±0.6)h;Cmax(199.8±39.3)ng/nl^-1和(196.6±35.1)ng/ml^-1;Tmax(1.0±0.1)h和(1.0±0.1)h;AUC(1643.8±295.6)ng.h.ml^-1和(1666.7±264.3)ng.h.ml^-1,单硝酸异山梨酯研制品片剂相对于对照品片剂生物利用度为(1  相似文献   

3.
棒曲霉UA—2木聚糖酶的蔗渣固态发酵   总被引:3,自引:0,他引:3  
棒曲霉(Aspergilusclavatus)UA-2固态发酵蔗渣产木聚酶的培养基为每克蔗渣加营养液5ml,初始pH8.5.营养液的适宜组成为每升含:NH4NO310g、K2HPO46g、MgSO4·7H2O0.75g、CaCl20.75g、FeSO4·7H2O11.25mg、MnSO4·H2O3.75mg、ZnSO43.0mg、CoCl24.5mg.在上述培养基中接入其湿重10%(W/W)的新鲜的UA-2种子曲,28℃培养108h,其木聚糖酶,滤纸降解酶和羧甲基纤维素酶的活力分别为2695.6、28.5和42.7u/g蔗渣.酶反应的最适pH5.0,最适温度50℃;在pH4.0~11.0内酶活性十分稳定.50℃保温1h,酶活剩余55%,8℃下放置23d,活力几乎不变.磷酸盐,半胱氨酸对酶有激活作用,EDTA和对氯汞本甲酸对酶有抑制作用  相似文献   

4.
在pH〈6.2的NaCl介质中,Ce的荧光为核酸所猝灭。20℃时小牛胸腺DNA,鱼精子DNA和酵母RNA对Ce的荧光猝灭在0-6.0μg/ml的浓度范围内符合方程ln(F0/f)=kc+b,在3.0-8.0μg/ml范围内却符合主程F0/F=kc+b。  相似文献   

5.
两种有机磷农药及其混配农药的毒力测定   总被引:7,自引:0,他引:7  
以马拉硫磷(0.45g/ml)、敌百虫(0.9g/ml)以及由该两种杀虫剂混配的农药「敌-马乳油(0.40g/ml)」为供试药剂,采用腹部注射法对中华稻蝗龄若虫进行毒力测定。结果显示24h各药剂的半致死剂量分别为:马拉硫磷14.22μg/g;敌百虫39.267μg/g;敌-马乳油11.39μg/g。这表明混配农药敌-马乳油对敌百虫和马拉硫磷增效作用。  相似文献   

6.
氯化钠介质中核酸对铈(Ⅲ)的荧光猝灭特性及其分析应用   总被引:1,自引:0,他引:1  
在pH<6.2的NaCl介质中,Ce(Ⅲ)的荧光(λex254.0nm和λem350.0nm)为核酸所猝灭.20℃时小牛胸腺(ct)DNA、鱼精子(fs)DNA和酵母(y)RNA对Ce(Ⅲ)的荧光猝灭在0~6.0μg/ml的浓度范围内符合方程ln(F0/F)=kc+b,在3.0~8.0μg/ml范围内却符合方程F0/F=kc+b,而在3.0~6.0μg/ml浓度范围内同时遵守上述二方程.猝灭过程与碱基的摩尔吸光系数大小有关.应用核酸对Ce(Ⅲ)的这种荧光猝灭特性可以灵敏的测定各种核酸  相似文献   

7.
目的:探讨替硝唑在唾液浓度和血浆浓度的相关性。方法:8 名健康男性志愿者交叉口服2 g 的替硝唑胶囊和片剂,用 H P L C 法测定其在血浆中浓度经时过程及相应时间点的唾液中浓度。结果:替硝唑胶囊的血浆及唾液中的t1/2ka 分别为(047 ±024) 、(063 ±038)h ,t1/2ke 分别为(1371 ±152) 、(1378 ±337)h , ρmax 分别为(5207 ±911) 、(4810 ±801) μg/m L, A U C 分别为(1 09298 ±11183) 、(1 01128 ±11520)μg·h/m L;替硝唑片剂的血浆及唾液中的t1/2ka 分别为(086±067) 、(078 ±052)h ,t1/2ke 分别为(1419 ±195) 、(1300 ±207)h ,ρmax 分别为(5107 ±1032) 、(4909 ±927)μg/m L, A U C 分别为(1 12300 ±12825) 、(1 04415 ±17954)μg·h/m L。结论:替硝唑在唾液和血浆中的药代动力学参数相似,均无显著性差异,替硝唑唾液与血浆浓度呈显著正相  相似文献   

8.
本文研究了铅溴络合物在高氯酸-磷酸-草酸介质中的极谱行为。确定底液组成为5%NaBr-11%HClO4-5%H3PO4-0.8%H2C2O4。工作曲线线性范围为0-150μg/50ml检测下限达0.01μg/ml体系选择性好,应用于实际样品的测定,获得满意结果。  相似文献   

9.
利用细胞松驰素B抑制栉孔扇贝Chllamys(Azumapecten)farreri受精卵的第一极体的放出和第一次有丝分裂获得四倍体,在20℃条件下,卵子受精后10min,0.5μg/ml的CB持续处理10min,20min抑制第一极体排出,结果三倍体率和四倍体率分别为38.38%,39.75%和28.42%,30.24%,在20℃条件下,卵子受精后1h,0.5μg/ml的CB持续处理10,15,  相似文献   

10.
利用畜禽专用氟喹酮类抗菌药-恩诺沙星对禽源致病性大肠杆菌采用试管法和纸片法进行了体外药敏试验。结果表明,不同厂家生产的恩诺沙星药物:百病消,普杀平,恩诺沙星对大肠杆菌O2的MIC分别为0.1μg/ml、0.2μg/ml、0.2μg/ml;MBC分别为0.2μg/ml、0.4μg/ml、0.4μg/ml。对大肠杆菌O78的MBC均为0。恩诺沙星新配溶液和放置一月后的药液对大肠杆菌O2的MIC为0.2  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.
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   

19.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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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