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电针对APP/PS1转基因小鼠海马低密度脂蛋白受体相关蛋白-1及其mRNA表达的影响 被引量:1
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作者 李芙 王鑫 +7 位作者 范盎然 李丽君 加吾拉.阿不力孜 白杨 步青云 高堂珂 李丽娜 薛卫国 《针灸临床杂志》 2015年第5期57-61,F0003,共6页
目的:研究电针是否是通过影响LRP1mRNA水平、提高LRP1的表达,从而促进脑内Aβ清除。方法:将4月龄APP/PS1转基因鼠,随机分为模型组、电针治疗组,以同窝同背景转基因阴性小鼠为正常对照组。电针干预"涌泉"、"百会"0.1... 目的:研究电针是否是通过影响LRP1mRNA水平、提高LRP1的表达,从而促进脑内Aβ清除。方法:将4月龄APP/PS1转基因鼠,随机分为模型组、电针治疗组,以同窝同背景转基因阴性小鼠为正常对照组。电针干预"涌泉"、"百会"0.1 m A,15 min/次,隔日1次,治疗6周。治疗后,以免疫组化法观察脑组织LRP1阳性表达,以Western blotting法检测海马LRP1表达,以Real-time PCR法检测海马LRP1mRNA表达。结果:LRP1表达于脑微血管内皮细胞、胶质细胞、神经元等处。模型组海马LRP1蛋白、LRP1mRNA相对表达量低于正常对照组(P<0.05),电针治疗组海马LRP1及LRP1mRNA比模型组有上升趋势,但差异无统计学意义(P>0.05)。结论:电针干预可能影响5月龄APP/PS1转基因小鼠海马内所有细胞LRP1及LRP1mRNA表达,可能是电针干预AD发病的潜在靶点,但实验方案还需进一步完善。 展开更多
关键词 电针 阿尔兹海默病 Β淀粉样蛋白 度脂蛋白受相关蛋白-1mRNA
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Artificial intelligence models based on non-contrast chest CT for measuring bone mineral density
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作者 DUAN Wei YANG Guoqing +6 位作者 LI Yang SHI Feng YANG Lian XIONG Xin CHEN Bei LI Yong FU Quanshui 《中国医学影像技术》 CSCD 北大核心 2024年第8期1231-1235,共5页
Objective To observe the value of artificial intelligence(AI)models based on non-contrast chest CT for measuring bone mineral density(BMD).Methods Totally 380 subjects who underwent both non-contrast chest CT and quan... Objective To observe the value of artificial intelligence(AI)models based on non-contrast chest CT for measuring bone mineral density(BMD).Methods Totally 380 subjects who underwent both non-contrast chest CT and quantitative CT(QCT)BMD examination were retrospectively enrolled and divided into training set(n=304)and test set(n=76)at a ratio of 8∶2.The mean BMD of L1—L3 vertebrae were measured based on QCT.Spongy bones of T5—T10 vertebrae were segmented as ROI,radiomics(Rad)features were extracted,and machine learning(ML),Rad and deep learning(DL)models were constructed for classification of osteoporosis(OP)and evaluating BMD,respectively.Receiver operating characteristic curves were drawn,and area under the curves(AUC)were calculated to evaluate the efficacy of each model for classification of OP.Bland-Altman analysis and Pearson correlation analysis were performed to explore the consistency and correlation of each model with QCT for measuring BMD.Results Among ML and Rad models,ML Bagging-OP and Rad Bagging-OP had the best performances for classification of OP.In test set,AUC of ML Bagging-OP,Rad Bagging-OP and DL OP for classification of OP was 0.943,0.944 and 0.947,respectively,with no significant difference(all P>0.05).BMD obtained with all the above models had good consistency with those measured with QCT(most of the differences were within the range of Ax-G±1.96 s),which were highly positively correlated(r=0.910—0.974,all P<0.001).Conclusion AI models based on non-contrast chest CT had high efficacy for classification of OP,and good consistency of BMD measurements were found between AI models and QCT. 展开更多
关键词 OSTEOPOROSIS bone density tomography X-ray computed artificial intelligence
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章怀太子墓壁画《仪卫图》与“画圣”吴道子
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作者 石瑜 《唐都学刊》 2009年第1期52-54,共3页
章怀太子墓室壁画是唐人物画中的最具代表性作品之一。特别是《仪卫图》的绘画风格和绘画技法,有"吴带当风"独特性。笔者认为,有很多历史线索和证据都在向我们表明,该作品的作者很有可能就是我国唐朝最著名的"画圣"... 章怀太子墓室壁画是唐人物画中的最具代表性作品之一。特别是《仪卫图》的绘画风格和绘画技法,有"吴带当风"独特性。笔者认为,有很多历史线索和证据都在向我们表明,该作品的作者很有可能就是我国唐朝最著名的"画圣"吴道子。 展开更多
关键词 李贤墓室壁画 吴道子 “疏体” “密体” 新风格 技法
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Effect of additives on properties of aluminium titanate ceramics 被引量:7
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作者 姜澜 陈晓燕 +1 位作者 韩国明 孟宇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第7期1574-1579,共6页
The influence of some additives on bulk density,phase composition,mechanical strength and thermal shock resistance of aluminium titanate (AT) ceramics was investigated.AT ceramics with different additives of MgO,SiO... The influence of some additives on bulk density,phase composition,mechanical strength and thermal shock resistance of aluminium titanate (AT) ceramics was investigated.AT ceramics with different additives of MgO,SiO2 and Fe2O3 were prepared by reaction sintering.Properties of AT ceramics were tested by using Archimedes,three-point bending and thermal cycling tests.It was found that additives of MgO,SiO2 and Fe2O3 or their compound additives are favorable to reduce the porosities of AT,enhance mechanical strength and thermal shock resistance.The role of additives can be rationalized in terms of promotion of sintering process,formation of new phases and influence on lattice constant c of AT ceramics. 展开更多
关键词 aluminium titanate ceramics ADDITIVE bulk density mechanical properties
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Linear numerical calculation method for obtaining critical point,pore fluid,and framework parameters of gas-bearing media 被引量:3
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作者 牛滨华 孙春岩 +2 位作者 闫国英 杨维 刘畅 《Applied Geophysics》 SCIE CSCD 2009年第4期319-326,393,共9页
Up to now, the primary method for studying critical porosity and porous media are experimental measurements and data analysis. There are few references on how to numerically calculate porosity at the critical point, p... Up to now, the primary method for studying critical porosity and porous media are experimental measurements and data analysis. There are few references on how to numerically calculate porosity at the critical point, pore fluid-related parameters, or framework-related parameters. So in this article, we provide a method for calculating these elastic parameters and use this method to analyze gas-bearing samples. We first derive three linear equations for numerical calculations. They are the equation of density p versus porosity Ф, density times the square of compressional wave velocity p Vp^2 versus porosity, and density times the square of shear wave velocity pVs^2 versus porosity. Here porosity is viewed as an independent variable and the other parameters are dependent variables. We elaborate on the calculation steps and provide some notes. Then we use our method to analyze gas-bearing sandstone samples. In the calculations, density and P- and S-velocities are input data and we calculate eleven relative parameters for porous fluid, framework, and critical point. In the end, by comparing our results with experiment measurements, we prove the viability of the method. 展开更多
关键词 linear equation numerical calculation gas-bearing media critical point pore fluid and framework elastic parameters
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EFFECTS OF BODY TEMPERATURE ON ELECTROCARDIOGRAMS OF LIZARD Eremias multiocellata * 被引量:2
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作者 李仁德 陈强 刘晒发 《Zoological Research》 CAS CSCD 1998年第4期269-276,共8页
Electrocardiograms (ECG) of Eremias multiocellata were studied at 5-35℃ in body temperature. Electrocardiogram wave intervals (R-R,P-R,QRS,T-P,and R-T) shortened while heart rate increased with the increasing of bod... Electrocardiograms (ECG) of Eremias multiocellata were studied at 5-35℃ in body temperature. Electrocardiogram wave intervals (R-R,P-R,QRS,T-P,and R-T) shortened while heart rate increased with the increasing of body temperature. The average heart rate was 14.6/min at 5℃,whereas it was 201/min at 35℃. The duration of wave intervals of ECG and the heart rate were related significantly to the body temperature (P<0.001). Among the components of a cardiac cycle the cardiac rest period (TP intervals) and the atria-ventricular conduction time (PR interval) were affected mostly by body temperature. In the other hand the ventricular depolarization and repolarization (QRS and R-T intervals) were relatively less affected by the body temperature. The increasing of heart rate with body temperature was mainly caused by the shortening of ECG wave intervals,and the T-P interval (the cardiac rest period) was shortened more noticeably than other intervals. 展开更多
关键词 Eremias multiocellata ELECTROCARDIOGRAM Body temperature
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Security of Application System 被引量:1
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作者 李小平 钟宏 +5 位作者 丁俨 向智 胡海生 吴学林 张琦 朱建学 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期198-202,共5页
A safe and reliable application system frame based on Internet and Intranet for Stock Supervision and Administration Council of China is built up. An all sided, multi tier and multi technical security method has be... A safe and reliable application system frame based on Internet and Intranet for Stock Supervision and Administration Council of China is built up. An all sided, multi tier and multi technical security method has been adopted, which includes identity recognition, data encryption, digital signature, Domino and WWW servers, access control list, directory service, certificate authorization server, IC card and so on. The recognition system based on CA server is a high efficient, convenient and reliable system. The encryption technology and security method are proved to be reliable. The recognition system is of high security and is worthy of being popularized in some places where some special security requirements need meeting. Multi tier technology can improve the security of database. Double keys method is a useful data encryption method. 展开更多
关键词 INTERNET/INTRANET identity recognition data encryption digital signature security mechanism
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DISTRIBUTIONS OF TRIPLET CODONS IN MESSENGER RNA SECONDARY STRUCTURES 被引量:1
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作者 张静 顾宝洪 +1 位作者 彭守礼 刘次全 《Zoological Research》 CAS CSCD 1998年第5期350-358,共9页
Analysis of the secondary structures of mRNAs which encode mature peptides shows that the location of each codon in mRNA secondary structure has a trend, which appears to be in agreement with the conformational proper... Analysis of the secondary structures of mRNAs which encode mature peptides shows that the location of each codon in mRNA secondary structure has a trend, which appears to be in agreement with the conformational property of the corresponding amino acid to some extent. Most of the codons that encode hydrophobic amino acids are located in stable stem regions of mRNA secondary structures, and vice versa, most of the codons that encode hydrophilic amino acids are located in flexible loop regions. This result supports the recent conclusion that there may be the information transfer between the three dimensional structures of mRNA and the encoded protein. 展开更多
关键词 Triplet codon Amino acid mRNA secondary structure
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Bending properties and fracture mechanism of C/C composites with high density preform 被引量:9
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作者 张明瑜 苏哲安 +1 位作者 李建立 黄启忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第8期1795-1800,共6页
C/C composites with banded structure pyrocarbon were fabricated by fast chemical vapor infiltration(CVI),with C3H6 as carbon source,N2 as carrier gas,and three-dimensional(3D) 12K PAN-based carbon fabric with high... C/C composites with banded structure pyrocarbon were fabricated by fast chemical vapor infiltration(CVI),with C3H6 as carbon source,N2 as carrier gas,and three-dimensional(3D) 12K PAN-based carbon fabric with high density of 0.94 g/cm3 as preform.Experimental results indicated that the fracture characteristics of C/C composites were closely related to the frequency of high-temperature treatment(HTT) at the break of CVI process.According to the load?displacement curves,C/C composites showed a pseudoplastic fracture after twice of HTT.After three times of HTT,load?displacement curves tended to be stable with a decreasing bending strength at 177.5 MPa.Delamination failure and intrastratal fiber fracture were observed at the cross-section of C/C composites by scanning electronic microscope.Because the content of pyrocarbon and fibers has a different distribution in layers,the C/C composites show different fracture characteristics at various regions,which leads to good toughness and bending strength. 展开更多
关键词 C/C composites chemical vapor infiltration(CVI) high density preform bending properties fracture mechanism
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Study on the Changes of Physiological Indexes of Water Spinach in Eutrophication Water 被引量:1
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作者 李艳蔷 李兆华 +2 位作者 姜应和 宛晶 赵丽娅 《Agricultural Science & Technology》 CAS 2010年第11期73-76,共4页
[Objective] Effect of hypoxic water culture on physiological characteristic of water spinach and its hypoxia tolerance were studied.[Method] Water spinach was planted in soil and eutrophication water by means of float... [Objective] Effect of hypoxic water culture on physiological characteristic of water spinach and its hypoxia tolerance were studied.[Method] Water spinach was planted in soil and eutrophication water by means of floating bed,respectively,and the change of physiological indexes including chlorophyll,proline(Pro),malondialdehyde(MDA),soluble sugar and soluble protein in water spinach leaves at mature stage was researched,while the hypoxia tolerance of water spinach and the effect of plant density on water spinach growth were discussed in our paper.[Result] In the hypoxic eutrophication water,the content of total chlorophyll,malondialdehyde,soluble sugar and soluble protein in water spinach leaves was lower than that of soil culture,with higher proline content,which showed that water spinach had better tolerance to hypoxic eutrophication water;the higher the plant density,the lower the chlorophyll content in water spinach leaves,and there was no significant effect of plant density on proline and malondialdehyde content,while soluble protein content was higher under high plant density.[Conclusion] The best plant density of water spinach was 66 plants per floating bed with the area of 2 m2,which could provide theoretical basis for the application of water spinach in floating bed. 展开更多
关键词 Water spinach Eutrophication water Plant density Physiological index
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Construction and Expression of Tp0453 Recombinant Protein of Treponema pallidum and Development of Indirect ELISA for Diagnosinq Syphilis 被引量:1
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作者 刘双全 吴移谋 +1 位作者 赵飞骏 曾铁兵 《Chinese Journal of Sexually Transmitted Infections》 2005年第1期30-34,共5页
Objectives: To clone and express Tp0453 outer membrane protein of Treponema pallidum, and to evaluate its significance in the serodiagnosis of syphilis. Methods: The immuno-dominant epitope of Tp0453 gene was amplif... Objectives: To clone and express Tp0453 outer membrane protein of Treponema pallidum, and to evaluate its significance in the serodiagnosis of syphilis. Methods: The immuno-dominant epitope of Tp0453 gene was amplified from the complete genome of T.pallidum by polymerase chain reactions (PCR), subcloned into the expression vector Pqe32 to generate recombinant plasmid Pqe32/Tp0453, and was then expressed in E. coli M15. The fusion protein was purified with Ni-NTA affinity purification. Indirect ELISA was developed to detect human serum IgG antibody to T. pallidum. Results: The recombinant Tp0453 protein was successfully expressed and purified. The recombinant protein had a molecular weight of approximately 32KDa.Indirect ELISA to the recombinant protein was developed.Sixty control sera were tested by ELISA and yielded a sensitivity of 100% (30/30) and a specificity of 100% (30/30). While testing for T. pallidum in human sera, the sensitivity and specificity of ELISA were 96.8% and 100%, respectively, when compared with TPPA test results. The concordance of results between the ELISA test and the TPPA test was 98.2%. Conclusion: The recombinant Tp0453 outer membrane protein elicited a strong immunoreaction to anti-T.pallidum IgG antibody and has great potential use in ELISA for the serodiagnosis of syphilis. 展开更多
关键词 Treponema pallidum recombinant protein SERODIAGNOSIS enzyme link immunosorbent assay
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Effect of Different Sowing Dates and Densities on Individual Morphological Development of Super Short-season Insect-resistant Cotton 被引量:4
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作者 李金才 唐光雷 李存东 《Agricultural Science & Technology》 CAS 2011年第4期533-536,共4页
[Objective] The paper was to explore the effect of different sowing dates and densities on individual morphological development of super short-season insect-resistant cotton,confirm their effects on vegetative and rep... [Objective] The paper was to explore the effect of different sowing dates and densities on individual morphological development of super short-season insect-resistant cotton,confirm their effects on vegetative and reproductive growth of cotton,so as to provide theoretical and practical guidance for sowing date and density management of cotton planting in Jidong cotton growing region in Yellow River Basin.[Method] With super short-season insect-resistant cotton"546"as materials,the effects of different sowing dates(sowing dateⅠ:May 20;sowing dateⅡ:June 2;sowing date Ⅲ:June 14)and densities(low density:120 000 plants/hm2;middle density:150 000 plants/hm2;high density:180 000 plants/hm2)on individual morphological development of super short-season insect-resistant cotton were explored.[Result] Different sowing dates and density treatments significantly affected the individual morphological development of super short-season insect-resistant cotton"546".The effectiveness of sowing date was higher than the effectiveness of density,and the effectiveness of sowing date on development of number of individual fruit branches was higher than that on plant height and stem diameter.[Conclusion] The regulation of sowing date and density during the cultivation process of super short-season insect-resistant cotton "546" in Jidong cotton growing region in Yellow River Basin could effectively promote vegetative and reproductive growth of cotton,strengthening its production base. 展开更多
关键词 Sowing date DENSITY Super short-season insect-resistant cotton Individual morphological development
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Study on the Polyploid Induction of Lycium ruthenicum Murr.
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作者 李晶 姚航 +2 位作者 曹后男 张楠 王蕾 《Agricultural Science & Technology》 CAS 2016年第9期2012-2016,共5页
With apical leaves of Lycium ruthenicum Murr as experimental material, the polyploids of L. ruthenicum were induced with colchicine solution, and total four polyploidy plants were identified by chromosome courts. The ... With apical leaves of Lycium ruthenicum Murr as experimental material, the polyploids of L. ruthenicum were induced with colchicine solution, and total four polyploidy plants were identified by chromosome courts. The results showed that tetraploid plants of L. ruthenicum were successfully induced with 300 mg/L of colchicine solution after 7 and 21 d of induction, with 400 mg/L of colchicine solution after 14 days of induction, and with 500 mg/L of colchicine solution after 7 days of induction, respectively. 展开更多
关键词 POLYPLOID Stomatal density CHROMOSOME COLCHICINE
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Development and Clinical Application of a Single-tube Nested PCR Method to Amplify the DNA Polymerase Ⅰ Gene of Treponema Pallidum 被引量:2
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作者 曾铁兵 吴移谋 +1 位作者 黄澍杰 吴志周 《Chinese Journal of Sexually Transmitted Infections》 2004年第2期101-104,i004,共5页
Objective: To develop a sensitive, specific and simple method for detection of extremely low numbers of T. pallidum in clinical specimens, as a significant addition to the serologic tests for syphilis diagnosis. Metho... Objective: To develop a sensitive, specific and simple method for detection of extremely low numbers of T. pallidum in clinical specimens, as a significant addition to the serologic tests for syphilis diagnosis. Methods: Double-tube nested PCR(DN-PCR) and single-tube nested PCR(SN-PCR) assays were performed to amplify specific fragments of the DNA poly-merase I gene(polA) of T. pallidum. Sensitivity and specificity of the two PCR assays were tested. Eighty-six whole blood specimens from persons with suspected syphilis were detected by the two nested PCR methods. The TPPA test was used as a comparison for detecting syphilis in sera from corresponding patients. Results: Only specific amplicons could be obtained during amplification of the T. pallidum polA gene and the detection limit was approximately 1 organism when analyzed on gel by the two PCR methods. Of 86 clinical specimens, 62 were positive by TPPA. Of these, 54 and 51 were positive by the DN-PCR and SN-PCR, respectively, which does not represent a statistically significant difference between the two PCR tests. Of 24 TPPA-negative specimens, 5 were positive by both DN-PCR assay and SN-PCR assay. Conclusion: The SN- polA PCR method is extremely sensitive, specific and easy to perform for detecting low numbers of T. pallidum in clinical blood specimens as a complementary to serology for syphilis diagnosis. 展开更多
关键词 nested polymerase chain reaction(PCR) DNA polymerase gene(polA) Treponema pallidum whole blood
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Numerical simulation of two-phase flow field in underwater sealing device based on dynamic mesh 被引量:1
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作者 张学伟 李强 吕梦柔 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第3期253-257,共5页
In order to speed underwater launch of minor-caliber weapons,a sealing device can be set in front of underwater muzzle to separate water,preventing the muzzle from water immersion.By establishing and simplifying the m... In order to speed underwater launch of minor-caliber weapons,a sealing device can be set in front of underwater muzzle to separate water,preventing the muzzle from water immersion.By establishing and simplifying the model of underwater weapon sealing device and unstructured mesh computing domain model based on computational fluid dynamics(CFD),dynamic mesh and user defined function(UDF),the N-S equation is solved and the numerical analysis and calculation of the complex two-phase flow inside the sealing device are carried out.The results show that the gas discharged from the sealing device is conducive to the formation of the projectile supercavity.When the projectile is launched at 5munder water,the shock wave before and after the projectile has impact on the box body up to 100 MPa,therefore the sealing device must be strong enough.The research results have the vital significance to the design of underwater weapon sealing device and the formation of the projectile supercavitation. 展开更多
关键词 two-phase flow SUPERCAVITATION sealing device computational fluid dynamics(CFD) dynamic mech
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Property of Dual-purposed Maca Powder as Medicine and Food
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作者 徐天才 薛润光 +2 位作者 杨少华 赵菊 谭敬菊 《Agricultural Science & Technology》 CAS 2012年第11期2409-2414,共6页
[Objective] The aim was to research property of maca and three plants' powders and process parameters of compound maca direct compression. [Method] Based on analysis data from SAS, bulk density, tap density, angle of... [Objective] The aim was to research property of maca and three plants' powders and process parameters of compound maca direct compression. [Method] Based on analysis data from SAS, bulk density, tap density, angle of repose and swelling of powders were studied as per single factor method and orthogonal exper- imental design. [Result] The test indicated that fillibilities of plant A and B, and maca powders are better and flowability plays an important role in fractional close of compound maca powder; plant A and B powders have a significant effect on bulk density of maca (P=0.0125), an extremely significant effect on swelling volume ratio (P=0.008 9) and little effect on tap density (g/ml); the optimal process condition of compound maca powder is as follows: A at 0.15 share; B at 0.10 share; C at 0.05 share; the optimal swelling volume ratio is at 2.459. [Conclusion] The technology is reasonable in formulation and satisfactory in fillibility, swelling ability, flowability, and it could serve as theoretical basis for the industrial production of maca tablets. 展开更多
关键词 Natural plant auxiliary materials MACA 'Powder micromeritics Orthogonatexperimental design
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Treponema pallidum and Haemophilus ducreyi DNA detection by A Multi-Nested Polymerase Chain Reaction
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作者 郑和平 黄进梅 +2 位作者 吴兴中 SylviaBruisten 胡玉山 《Chinese Journal of Sexually Transmitted Infections》 2004年第2期89-91,i003,共4页
Objectives: To develop a multi-nested polymerase chain reaction in an assay to detect early Treponema pallidum and Haemophilius ducreyi DNA in the swabs of genital ulcers. Methods: Four pairs of outer and inner primer... Objectives: To develop a multi-nested polymerase chain reaction in an assay to detect early Treponema pallidum and Haemophilius ducreyi DNA in the swabs of genital ulcers. Methods: Four pairs of outer and inner primers, specific to the basic membrane protein gene of Treponema pallidum and to the 16s rRNA gene of H ducreyi were synthesized. The multi-nested PCR was developed and applied to detect Treponema pallidum and Haemophilus dicreyi in clinical swabs. Result: The two samples of standard strains of Haemophilus ducreyi and one Treponema pallidum were amplified and showed 309-bp rRNA gene of Haemophilus ducreyi and 506-bp DNA of Treponema palidum, respectively. Out of 51 samples of genital ulcer detected, 29 showed Treponema pallidum positive product and no Haemophilus ducreyi DNA was found. Conclusion: The multi-nested PCR for Treponema pallidum and Haemophilus ducreyi could be useful for early detection and distinguishing diagnosis between syphilis and chancroid. 展开更多
关键词 Multi-nested PCR Treponema pallidum Haemophilus ducreyi
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Hydrolysis Mechanism of the NAMI-A-type Antitumor Complex (HL)[trans-RuCl4L(dmso-S)] (L=1-methyl-l,2,4-triazole)
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作者 陈兰美 陈锦灿 +3 位作者 廖思燕 刘江琴 罗辉 郑康成 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第4期383-390,I0003,共9页
The hydrolysis process of Ru(III) complex (HL)[trans-RuC14L(dmso-S)] (L=l-methyl-l,2,4- triazole and dmso-S=S-dimethyl sulfoxide) (1), a potential antitumor complex similar to the well-known antitumor agent ... The hydrolysis process of Ru(III) complex (HL)[trans-RuC14L(dmso-S)] (L=l-methyl-l,2,4- triazole and dmso-S=S-dimethyl sulfoxide) (1), a potential antitumor complex similar to the well-known antitumor agent (Him)[trans-RuC14 (dmso-S)(im)] (NAMI-A, im=imidazole), was investigated using density functional theory combined with the conductor-like polarizable continuum model approach. Tile structural characteristics and the detailed energy profiles for the hydrolysis processes of this complex were obtained. For the first hydrolysis step, complex 1 has slightly higher barrier energies than the reported anticancer drug NAMI-A, and the result is in accordance with the experimental evidence indicating larger half-life for complex 1. For the second hydrolysis step, the formation of cis-diaqua species is thermodynamic preferred to that of trans isomers. In addition, on the basis of the analysis of electronic characteristics of species in the hydrolysis process, the trend in nucleophilic attack abilities of hydrolysis products by pertinent biomolecules is revealed and predicted. 展开更多
关键词 NAMI-A-type complex Anticancer activity HYDROLYSIS Density functional theory Conductor-like polarizable continuum model
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DENSE DISPARITY MAP ESTIMATION USING GENETIC ALGORITHMS 被引量:1
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作者 王彪 沈春林 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期184-191,共8页
An approach to addressing the stereo correspondence problem is presented using genetic algorithms (GAs) to obtain a dense disparity map. Different from previous methods, this approach casts the stereo matching as a mu... An approach to addressing the stereo correspondence problem is presented using genetic algorithms (GAs) to obtain a dense disparity map. Different from previous methods, this approach casts the stereo matching as a multi-extrema optimization problem such that finding the fittest solution from a set of potential disparity maps. Among a wide variety of optimization techniques, GAs are proven to be potentially effective methods for the global optimization problems with large search space. With this idea, each disparity map is viewed as an individual and the disparity values are encoded as chromosomes, so each individual has lots of chromosomes in the approach. Then, several matching constraints are formulated into an objective function, and GAs are used to search the global optimal solution for the problem. Furthermore, the coarse-to-fine strategy has been embedded in the approach so as to reduce the matching ambiguity and the time consumption. Finally, experimental results on synthetic and real images show the performance of the work. 展开更多
关键词 stereo correspondence disparity map genetic algorithms coarse-to-fine strategy
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Tempo-Spatial Variations in Stomatal Conductance, Aperture and Density of Ligustrum sinense Acclimated to Different Light Environments 被引量:5
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作者 张守仁 马克平 陈灵芝 《Acta Botanica Sinica》 CSCD 2002年第10期1225-1232,共8页
There was heterogeneous distribution in stomatal conductance (g-s) and stomatal aperture for both high- and low-light leaves of Ligustrum sinense Lour. in four designated positions within a leaf. Linear or exponential... There was heterogeneous distribution in stomatal conductance (g-s) and stomatal aperture for both high- and low-light leaves of Ligustrum sinense Lour. in four designated positions within a leaf. Linear or exponential or polynomial relationships between g-s and stomatal aperture were found when regression of g-s and stomatal aperture was established. Statistical analysis revealed that the relationship between g-s and stomatal aperture for high-light leaves was more significant than that of low-light leaves. A linear relationship between g-s and stomatal aperture existed in both positions 1 and 3 for both high- and low-light leaves. The stomatal density of the low-light leaves was much lower than that of the high-light leaves. The sensitivity of stomata to changing environment for high-light leaves was higher than that for low-light leaves, which may also relate to the higher stomatal density for the high-light leaves. 展开更多
关键词 ACCLIMATION gas exchange light environment MICROSCOPY stomatal heterogeneity
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