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621.
622.
An extremely rapid assay technique for antibodies has been developed utilizing protein A or protein G bound to Perfusion Chromatography support matrices. Either dilute or concentrated samples are directly injected on a column that selectively binds antibody, which is quantitated directly by elution and UV absorbance. Due to the unique mass transport characteristics of the supports, total assay cycle times are typically 1 minute or less, with assays as short as 15 seconds possible. The assay system can accurately quantitate a 100,000:1 or greater dynamic range in sample concentration without sample dilution, is extremely repeatable and is easy to automate with conventional HPLC systems. Assay of antibodies in a wide range of sample types has been demonstrated. 相似文献
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There is an ongoing race between bacterial evolution and medical advances. Pathogens have the advantages of short generation times and horizontal gene transfer that enable rapid adaptation to new host environments and therapeutics that currently outpaces clinical research. Antibiotic resistance, the growing impact of nosocomial infections, cancer-causing bacteria, the risk of zoonosis, and the possibility of biowarfare all emphasize the increasingly urgent need for medical research focussed on bacterial pathogens. Bacterial glycoproteins are promising targets for alternative therapeutic intervention since they are often surface exposed, involved in host-pathogen interactions, required for virulence, and contain distinctive glycan structures. The potential exists to exploit these unique structures to improve clinical prevention, diagnosis, and treatment strategies. Translation of the potential in this field to actual clinical impact is an exciting prospect for fighting infectious diseases. 相似文献
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By growing cells in the presence of 3 mM thymidine and 5-azadeoxycytidine up to 20% of DNA cytosines have been substituted with azacytosine. No substitution was obtained on incubating with 5-methyldeoxycytidine. Azacytosine-substituted DNA has a very low level of 5-methylcytosine and cells, which survive azadeoxycytidine treatments maintain this low level of methylation in the absence of the drug. The DNA of such cells is undermethylated fairly evenly in all classes of DNA e.g., satellite and unique DNA. Incubation of cells in azadeoxycytidine leads to high cell mortality which is not related to the lack of DNA methylation but may be linked to the altered interactions of proteins with the substituted DNA. This effect, rather than reduced DNA methylation, may be the cause of differentiative changes observed on treatment of cells with 5-azacytidine. 相似文献
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C Fulton 《The Journal of protozoology》1983,30(2):192-198
629.
Takayo Ota Haruka Asahina Se-Hyung Park Qing Huang Takashi Minegishi Nelly Auersperg Peter CK Leung 《Reproductive biology and endocrinology : RB&E》2008,6(1):49
Background
HOX cofactors enhance HOX binding affinities and specificities and increase HOX's unique functional activities. The expression and the regulation of HOX cofactors in human ovaries are unknown. 相似文献630.