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1.
SALVIAFLASIDEANDSALVIAFLASIDEMETHYLESTERTWONEWDEPSIDICGLYCOSIDESFROMSALVIAFLAVA¥LiMinAHAO;WenYiHE;XiaoTianLIANGandLianNiangLI...  相似文献   

2.
INULOSIDE A AND B. TWO NEW DITERPENE GLYCOSIDES FROM INULA BRITANNICAL. VAR CHINENSISINULOSIDEAANDB.TWONEWDITERPENEGLYCOSIDES...  相似文献   

3.
ASTERYUNNANOSIDE E, A NEW TRITERPENOID SAPONIN FROM ASTER YUNNANENSIS FRANCHASTERYUNNANOSIDEE,ANEWTRITERPENOIDSAPONINFROMASTE...  相似文献   

4.
OPTICALLYACTIVEAMINOACIDSWITHHIGHLYBRANCHEDSIDECHAIN(Ⅱ):SYNTHESISANDRESOLUTIONOFRACEMIC2-ACETAMIDO-7,7-DIMETHYLOCTANOICACIDAN...  相似文献   

5.
A NOVEL IRIDOID GLUCOSIDE ISOLATED FROM LAMIOPHLOMIS ROTATAANOVELIRIDOIDGLUCOSIDEISOLATEDFROMLAMIOPHLOMISROTATA¥JinHaiYI;YanC...  相似文献   

6.
CHEMICAL INCORPORATING INSECTICIDES 1.SYNTHESIS OF NEWPYRETHROIDS WITH ORGANOPHOSPHATE AS POTENTIAL INSECTICIDESCHEMICALINCOR...  相似文献   

7.
α-AMIDOALKYLATION VIA SULFONES:TOWARDS THE SYNTHESIS OF ANT VENOM ALKALOIDSα-AMIDOALKYLATIONVIASULFONES:TOWARDSTHESYNTHESISOF...  相似文献   

8.
SYNTHESISANDANTI-LIPIDPEROXIDATIONACTIVITYOFAMINOACIDDERIVATIVESOFEBSELEN¥YiagXiaXIAO;XiuFangLIU;HanShengXU(DepartmentofChemi...  相似文献   

9.
7,2'-DIDESACETOXY AUSTROSPICATINE, A NEW TAXANOID FROM THE BARKS OF TAXUS WALLICHIANA ZUCC7,2'-DIDESACETOXYAUSTROSPICATINE,AN...  相似文献   

10.
SYNTHESIS OF STEREO-ISOMERS OF SECOCLAUSENAMIDE Ⅰ AND SECODEMETHYLCLAUSENAMIDE ⅡSYNTHESISOFSTEREO-ISOMERSOFSECOCLAUSENAMIDEⅠA...  相似文献   

11.
Aptamers have recently emerged as an excellent alternative to antibodies because of their inherent stability and ease of modification. In this paper, we describe the development of an aptamer-based surface for capture of cells expressing CD4 antigen. The glass or silicon surfaces were modified with amine-terminated silanes and then modified with thiolated RNA aptamer against CD4. Modification of the surface was first characterized by ellipsometry to demonstrate assembly of biointerface components and to show specific capture of recombinant CD4 protein. Subsequently, surfaces were challenged with model lymphocytes (cell lines) that were either positive or negative for CD4 antigen. Our experiments show that aptamer-functionalized surfaces have similar capture efficiency to substrates containing anti-CD4 antibody. To mimick capture of specific T-cells from a complex cell mixture, aptamer-modified surfaces were exposed to binary mixtures containing Molt-3 cells (CD4+) spiked into Daudi B cells (CD4-). 94% purity of CD4 cells was observed on aptamer-containing surfaces from an initial fraction of 15% of CD4. Given the importance of CD4 cell enumeration in HIV/AIDS diagnosis and monitoring, aptamer-based devices may offer an opportunity for novel cell detection strategies and may yield more robust and less expensive blood analysis devices in the future.  相似文献   

12.
Synthetic peptides for AIDS research   总被引:1,自引:0,他引:1  
  相似文献   

13.
We have developed a microfabricated biochip that enumerates CD4+ T lymphocytes from leukocyte populations obtained from human blood samples using electrical impedance sensing and immunoaffinity chromatography. T cell counts are found by obtaining the difference between the number of leukocytes before and after depleting CD4+ T cells with immobilized antibodies in a capture chamber. This differential counting technique has been validated to analyze physiological concentrations of leukocytes with an accuracy of ~9 cells per μL by passivating the capture chamber with bovine serum albumin. In addition, the counter provided T cell counts which correlated closely with an optical control (R(2) = 0.997) for CD4 cell concentrations ranging from approximately 100 to 700 cells per μL. We believe that this approach can be a promising method for bringing quantitative HIV/AIDS diagnostics to resource-poor regions in the world.  相似文献   

14.
External quality assessment (EQA) of CD4 testing is important for clinically monitoring of patients with HIV/AIDS. EQA materials are limited to blood samples from normal blood donors with normal CD4+ T-lymphocyte levels. This study aimed to develop low-CD4+ T-lymphocyte blood samples for CD4 EQA. CD4+ T-lymphocyte-depleted blood samples were prepared using a magnetic bead separation technique. These CD4+ T-lymphocyte-depleted blood samples were mixed with undepleted whole blood samples to obtain low-CD4+ T-lymphocyte blood samples. The percentage and the number of CD4+ T-lymphocytes were determined using a flow cytometer. An evaluation study of this low-CD4+ T-lymphocyte blood sample was performed by sending to participating laboratories to investigate the potential use as CD4 EQA material. Our results showed that a magnetic separation technique could be used to prepare low-CD4+ T-lymphocyte blood samples. CD4+ T-lymphocytes in the low-CD4+ T-lymphocyte blood samples ranged from 15 % to 18 % and 160–300 cell/μl, respectively. In addition, CD4 testing of our low-CD4+ T-lymphocyte blood samples could be achieved following both the single- and the dual-platform flow cytometric approaches. A pilot EQA investigation revealed that the CV values of the number and percentage of CD4+ T-lymphocytes were 14 % and 10 %, respectively. Having the low-CD4+ T-lymphocyte blood samples in our CD4 EQA program should ensure reliability and credibility of CD4 testing in Thailand and other resource-poor countries.  相似文献   

15.
本文对AIDS 病毒抗原及其靶细胞(CD+4 ) 检测方法的研究进展作了较系统的评述。深入分析了gp 120、CD4 受体分子与小肽的相互作用。并给出了抗A IDS 病毒药物分析方法的最新研究动向。  相似文献   

16.
Yun H  Bang H  Min J  Chung C  Chang JK  Han DC 《Lab on a chip》2010,10(23):3243-3254
A portable flow cytometer has been recognized as an important tool for many clinical applications such as HIV/AIDS screening in developing countries and regions with limited medical facilities and resources. Conventional flow cytometers typically require multiple detectors for simultaneous identification of multiple subsets of immune cell. To minimize the number of detectors toward portable flow cytometry or to analyze multi-parametric cellular information with minimum number of detectors in conventional flow cytometers, we propose a versatile multiplexed cell-counting method using functional silica nanoparticles (SiNPs). FITC-doped SiNPs, which are 100 times brighter than the FITC molecules itself, were used as new intensity-based fluorescent dye complexes to simultaneously measure two subsets of leukocytes using a single detector. CD45(+)CD4(+) cells tagged with these FITC-doped SiNPs were 50 times brighter than CD45(+)CD4(-) cells tagged only with FITC. To make the overall system compact, a disposable microchip flow cytometer that does not require sheath flow was developed. Combining these dye-doped SiNPs based detection schemes and the sheathless microchip flow cytometer scheme, we successfully identified and counted two subsets of leukocytes simultaneously (R(2) = 0.876). These approaches can be the building blocks for a truly portable and disposable flow cytometer for various clinical cytometry applications.  相似文献   

17.
微量元素与艾滋病相关标志物   总被引:3,自引:2,他引:1  
人类免疫缺陷病毒(HIV)感染病程监督是防治艾滋病的重要措施和手段。阐述了微量元素在HIV病变进程中的变化及与其它相关标志物的关系,内容包括:微量元素与HIV病变、微量元素与CD4淋巴细胞、微量元素与谷胱甘肽、微量元素与HIV消瘦综合征,以及微量元素与炎性反应标志等5个方面。迄今的研究表明,微量元素可以作为反映HIV感染疾病进展的一种新的替代标志物。  相似文献   

18.
Human immunodeficiency virus (HIV) diagnostics are urgently needed in resource-scarce settings. Monitoring of HIV-infected patients requires accurate counting of CD4+ T lymphocytes. However, the current methods for enumeration of CD4+ T lymphocytes are of high cost, technically complex and time-consuming. In this paper, we developed a simple, rapid and inexpensive one-step immunomagnetic method for separating and counting CD4+ T lymphocytes on microfluidic devices with enlarged reaction chambers. CD4+ T lymphocytes were successfully separated and captured from the cell suspension obtained from mouse thymus. CD4 counts were determined under an optical microscope in a rapid and simple format. In order to acquire the maximum efficiency of cell capture, relative parameters were investigated, including section area of the reaction chamber and injection flow rate of the cell suspension. The enlarged reaction chamber with two symmetrical cone-shaped ends was helpful for cell capture, and the maximum capability of captured CD4+ T lymphocytes was about 700 cells μL−1. Our investigations avoided the complex sample pre-treatment, and the entire analysis time was significantly reduced to 15 min. This CD4 counting microdevice had the potential to reduce the cost for HIV diagnosis in resource-limited settings.  相似文献   

19.
Structural features (orientation of the carboxyl group, ring puckering), electronic absorption, and circular dichroism spectra of 4-alkyl- and 4-aryl-dihydropyrimidones 1-5 are calculated by semiempirical (AM1, INDO/S), ab initio (HF/6-31G, CIS/6-31G, RPA/6-31G), and density functional theory (B3LYP/6-31G) methods. These calculations allow an assignment of the absolute configuration by comparison of simulated and experimental CD spectra. Although the ab initio methods greatly overestimate electronic transition energies, the general appearance of the experimental CD spectra is quite nicely reproduced by these calculations. Thus, comparison of experimental with calculated CD spectra is a reliable tool for the assignment of the absolute configuration. For 4-methyl derivatives 1, the first enantiopure DHPM examples with no additional aromatic substituent, the stereochemistry at C4 provided by the theoretical results is confirmed by X-ray structure determination of the diastereomeric salt 6. Additional support is the consistent HPLC elution order found for all investigated DHPMs on a cellulose-derived chiral stationary phase.  相似文献   

20.
Quick and accurate direct and indirect circular dichroism (CD) spectrometric methods were developed for the simultaneous determination of ethisterone (17alpha-ethinyl-17-hydroxy-4-androstene-3-one) and its delta(5)-isomer (delta(5)-ethisterone). The direct method is based on the selective negative Cotton effect of the delta(4)-3-oxo group in ethisterone (negative maximum at 348 nm in dioxan) and measurement of the ellipticity at 296 nm (positive maximum of delta(5)-ethisterone), where the measured ellipticity is the sum of those of the two isomers. In the indirect procedure delta(5)-ethisterone is transformed to ethisterone by base-catalysed isomerization and the ellipticities are measured at 339 nm in ethanol before and after isomerization. Preliminary experiments show the usefulness of CD detector in the HPLC determination of the mixture of the isomers. A major advantage of the direct CD spectrometric and the HPLC/CD methods is that the delta(5)-isomer with extremely low UV activity can also be directly measured with high sensitivity.  相似文献   

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