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91.
以2-噻吩甲酰三氟丙酮(TTA)为第一配体,邻菲罗啉(o-Phen)为第二配体,利用共沉淀法合成一系列钐钆共掺杂荧光配合物,并优化了该系列荧光配合物的合成条件(反应温度、体系pH、稀土离子相对含量).将最优条件合成的Sm0.5 Gd0.5 TTA3(o-Phen)荧光配合物粉末用于常见光滑非渗透性客体表面潜在手印的显现...  相似文献   
92.
The development of the anti-malaria vaccine holds a promising future in malaria control. One of the anti-malaria vaccine strategies known as the transmission-blocking vaccine (TBV) is to inhibit the parasite transmission between humans and mosquitoes by targeting the parasite gametocyte. Previously, we found that P48/45 included in the 6-Cysteine protein family shared by Plasmodium sp. We also detected vaccine properties possessed by all human-infecting Plasmodium and could be used as a cross-species anti-malaria vaccine. In this study, we investigated the efficacy of P48/45 through the ancestral and consensus reconstruction approach. P48/45 phylogenetic and time tree analysis was done by RAXML and BEAST2. GRASP server and Ugene software were used to reconstruct ancestral and consensus sequences, respectively. The protein structural prediction was made by using a psipred and Rosetta program. Each protein characteristic of P48/45 was analyzed by assessing hydrophobicity and Post-Translational Modification sites. Meanwhile, the Epitope sequence for B-cell, T-cell, and HLA was determined using an immunoinformatics approach. Lastly, molecular docking simulation was done to determine native binding interactions of P48/45-P230. The result showed a distinct protein characteristic of ancestral and consensus sequences. The immunogenicity analysis revealed the number of epitopes in the ancestral sequence is greater than the consensus sequence. The study also found a conserved epitope located in the binding site and consists of specific Post-Translational Modification sites. Hence, our research provides detailed insight into ancestral and consensus P48/45 efficacy for the cross-species anti-malaria vaccine.  相似文献   
93.
Putrajeevak (Putranjiva roxburghii Wall.; synonym Drypetes roxburghii (Wall.) Hurus) seeds have been used since ancient times in the treatment of infertility in the Ayurvedic system of medicine in India. In this study, the oil component of Putrajeevak seeds (PJSO) was extracted using the supercritical fluid extraction (SCFE) method using liquid CO2 and the constituents were analyzed using gas chromatography-flame ionized detectorand high-performance thin-layer chromatography. PJSO contained trace amounts of β-sitosterol with oleic and linoleic acids as the major fatty acid constituents. Male and female zebrafish were mutagenized with N-ethyl-N-nitrosourea (ENU) and fish that produced less than 20 viable embryos were selected for the study. SCFE oil extracts from the P. roxburghii seeds were used in this study to reverse fertility impairment. The mutant fish were fed with PJSO for a period of 14 days and the rates of fertility, conception, and fecundity were determined with wild-type healthy fish as a breeding partner. Treatment with PJSO increased the ovarian follicle count as well as the number of mature eggs, while reducing the number of ovarian cysts. Sperm count as well as sperm motility were greatly enhanced in the ENU-mutagenized male zebrafish when treated with PJSO. The results obtained in this study demonstrate the effectiveness of P. roxburghii seed oil in reversing impaired fertility in both male and female zebrafish models.  相似文献   
94.
新型螺环单体的合成和自由基聚合反应的研究王宏鲁剑涛冯品珍(中国科学技术大学研究生院化学部北京100039)关键词自由基聚合,新单体合成,螺环单体,自由基共聚虽然离子型开环聚合早已为人熟知,但是自由基开环聚合反应的研究和应用开发还刚刚起步....  相似文献   
95.
Four new stationary phases for HPLC were prepared by modifying silica gel with a trifrnctional aminoalkyl silane. A conjugated π-electron system was linked to the amino group either directly or with a carboxylic anhydride as a spacer in between. Characterization and dynamic measurements of the new stationary phases were performed by solid state NMR spectroscopy. The results of the 29si and 13C CP/MAS techniques were compared with the recently developed 1H MAS-only technique. Despite strong homonuclear dipole-dipole interactions it was possible to obtain well resolved 1H MAS spectra of those stationaru phases with a high degree of crosslinking. Limited mobility of the aromatic ligand fragments is common for all examined stationaryu phases. The chromatographic properties of the new phases were tested by their ability tio sepatate a mixture of eight PAHS. It could be shown that the π-π interaction mechanism is responsible for the separation of the eight PAHs, because the elution order of the PAHs did not changem despite the use of both a nonpolar mobile phase (n-heptane) and a polar mobile phase (methanol/ water mixture).  相似文献   
96.
Phospholipase A2 (PLA2) enzymes were first recognized as an enzyme activity class in 1961. The secreted (sPLA2) enzymes were the first of the five major classes of human PLA2s to be identified and now number nine catalytically-active structurally homologous proteins. The best-studied of these, group IIA sPLA2, has a clear role in the physiological response to infection and minor injury and acts as an amplifier of pathological inflammation. The enzyme has been a target for anti-inflammatory drug development in multiple disorders where chronic inflammation is a driver of pathology since its cloning in 1989. Despite intensive effort, no clinically approved medicines targeting the enzyme activity have yet been developed. This review catalogues the major discoveries in the human group IIA sPLA2 field, focusing on features of enzyme function that may explain this lack of success and discusses future research that may assist in realizing the potential benefit of targeting this enzyme. Functionally-selective inhibitors together with isoform-selective inhibitors are necessary to limit the apparent toxicity of previous drugs. There is also a need to define the relevance of the catalytic function of hGIIA to human inflammatory pathology relative to its recently-discovered catalysis-independent function.  相似文献   
97.
A rapid capillary electrochromatography (CEC) method was developed to separate five structurally related steroid compounds from the production line of steroid hormones. The separation was performed on a Hypersil C8 MOS and Unimicro C18 stationary phases using acetonitrile (ACN), methanol (MeOH), and tetrahydrofuran (THF) as organic modifiers and tris(hydroxymethyl)aminomethane (Tris) as buffer additive. The Hypersil C8 MOS stationary phase performed best together with ACN as organic modifier and Tris buffer. The method was extensively tested for ruggedness with respect to sensitivity to temperature, ACN composition, pH change, concentration of Tris buffer, injected plug length, and run‐to‐run and day‐to‐day repeatability. The minimal detectable concentration and amount were investigated for quantification purposes. The developed CEC method was shown to be fast, rugged, and well suited for quantification of the steroids under study.  相似文献   
98.
The antibiotic pipeline has failed to keep pace with the rise of multidrug resistant tuberculosis and extensively drug-resistant tuberculosis pathogens. Naturally occurring peptides provide a rich source of lead compounds for developing novel pharmaceuticals with high selectivity and potency. Given the vast number of naturally-occurring bioactive cyclic peptides identified so far, the following digest highlights several cyclic peptides, discovered in the preceding decade, that exhibit promising activity against Mycobacterium tuberculosis.  相似文献   
99.
以常规型飞行时间质谱仪为基础,通过配置移动平台、样品杆、工业相机、LED灯源、工业显示屏等部件,研制了一套飞行时间质谱仪用固体样品自动进样系统,实现了固体有机样品的直接进样分析。该装置具有一定的普适性,可为相关实验室设备升级改造提供借鉴和参考。该装置可进行难溶未知有机化合物的结构剖析,实现目标物的快速筛查,且操作人员可实时观测锥孔处样品状态并可软件操控进样位置,实现人机分离的自动化测试。  相似文献   
100.
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