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High-performance anion-exchange chromatography with pulsed amperometric detection (HPAE-PAD) is an established technique for the carbohydrate analysis of glycoproteins. HPAE-PAD is routinely used for determinations of monosaccharide, sialic acid, mannose-6-phosphate (M-6-P), and oligosaccharide contents of a glycoprotein. This is true for both the initial investigation of a glycoprotein and routine assays of recombinant therapeutic glycoproteins. This contribution reviews the fundamentals of HPAE-PAD, recent technological improvements, and advances in the last ten years in its application to carbohydrate analysis of glycoproteins. The application areas reviewed include monosaccharide determinations, sialic acid determinations, M-6-P determinations, sugar alcohol determinations, analysis of polysialic acids, neutral and charged oligosaccharide analysis, following glycosidase and glycosyltransferase reactions, and coupling HPAE-PAD to mass spectrometry (MS).  相似文献   
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Low-input dry meadows are habitats of high nature value. More and more, less time-consuming harvesting techniques replace different steps of the traditional hay making process. The use of leaf blowers instead of rakes for hay making became popular in the last ten years in Switzerland. Thus, we set up a case study to test effects on the conservation value. The studied dry meadow of high nature value is located in the municipality of Stans (Switzerland). After five years no significant differences between blown and raked plots in species richness, richness of target an indicator species, medium plant-indicator values, i.e. nutrients, humidity, light or in the species assemblages were observed. From 2010 until 2014 the moss cover increased in all plots. The differences between raked and blown plots were not significant. In 2015, however, the difference between the two treatments increased to 13%. While the moss cover of the blown plots remained at 20%, the moss cover of the raked plots dropped to 7%. These results from only one case study and only a short observation period of five years do not allow a generalization, but they give a first impression of the short-term effects. We recommend managers of dry meadows with high nature values to keep an eye on the change of moss cover and potential changes of conservation values when leaf blowers instead of rakes are used for hay harvesting.  相似文献   
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To identify and analyse precursor cells of neuronal and glial cell lineages during the early development of the chick peripheral nervous system, monoclonal antibodies were raised against a population of undifferentiated cells of E6 dorsal root ganglia (DRG). Non-neuronal cells of E6 DRG express surface antigens that are recognized by four monoclonal antibodies, G1, G2, GLI 1 and GLI 2. The proportion of non-neuronal cells in DRG that express the GLI 1 antigen is very high during ganglion formation (80% at E4) and decreases during later development (15% at E14). GLI 2 antigen is expressed only on a minority of the cells at E6 and increases with development. The G1 and G2 antigens are expressed on about 60-80% of the cells between E6 and E14. All cells that express the established glia marker O4 are also positive for the new antigens. In addition, it was demonstrated that GLI 1-positive cells from early DRG, which are devoid of O4 antigen, could be induced in vitro to express the O4 antigen. Thus, the antigen-positive cells are considered as glial cells or glial precursor cells. Surprisingly, the antigen expression by satellite cells of peripheral ganglia is dependent on the type of ganglion: antigens G1, G2 and GLI 1 were not detectable on glial cells of lumbosacral sympathetic ganglia and GLI 2 was expressed only by a small subpopulation. These results demonstrate an early immunological difference between satellite cells of sensory DRG and sympathetic ganglia.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Recent advances in the use of microsatellite markers and the development of comparative gene mapping techniques have made the construction of high resolution genetic maps of livestock species possible. Framework and comprehensive genetic linkage maps of porcine chromosome 6 have resulted from the first international effort to integrate genetic maps from multiple laboratories. Eleven highly polymorphic genetic markers were exchanged and mapped by four independent laboratories on a total of 583 animals derived from four reference populations. The chromosome 6 framework map consists of 10 markers ordered with high local support. The average marker interval of the framework map is 15.1 cM (sex averaged). The framework map is 135, 175 and 109 cM in length (for sex averaged, female and male maps, respectively). The comprehensive map includes a total of 48 type I and type II markers with a sex averaged interval of 3.5 cM and is 166, 196 and 126 cM (for sex averaged, female and male maps, respectively). Additional markers within framework map marker intervals can thus be selected from the comprehensive map for further analysis of quantitive trait loci (QTL) located on chromosome 6. The resulting maps of swine chromosome 6 provide a valuable tool for analysing and locating QTL.  相似文献   
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Remarkably high estrogenic activity was observed for 3-hydroxy93-estra-1,3,5 (10)-triene-ll,17-dione despite its unusual bent conformation. The 9α epimer of this compound has markedly less activity despite the fact that its overall shape is nearly identical to that of estrone. The potency of these compounds in enhancing uterine weight in Fischer rats and reducing ovarian weight in parabiosed rats was compared with that of estrone, and the structures were unambiguously identified by X-ray crystallographic study. The results underscore the importance of the phenolic ring A to estrogenic activity, and suggest a tolerance of the putative estrogenic receptor to flexibility in overall molecular shape.  相似文献   
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It has recently been demonstrated that mutations in the gene for Bruton's tyrosine kinase (BTK) are responsible for X-linked agammaglobulinemia. Southern blot analysis and sequencing of cDNA were used to document deletions, insertions, and single base pair substitutions. To facilitate analysis ofBTK regulation and to permit the development of assays that could be used to screen genomic DNA for mutations inBTK, we determined the genomic organization of this gene. Subcloning of a cosmid and a yeast artificial chromosome showed thatBTK is divided into 19 exons spanning 37 kilobases of genomic DNA. Analysis of the region 5' to the first untranslated exon revealed no consensus TATAA or CAAT boxes; however, three retinoic acid binding sites were identified in this region. Comparison of the structure ofBTK with that of other nonreceptor tyrosine kinases, includingSRC,FES, andCSK, demonstrated a lack of conservation of exon borders. Information obtained in this study will contribute to our understanding of the evolution of nonreceptor tyrosine kinases. It will also be useful in diagnostic studies, including carrier detection, and in studies directed towards gene therapy or gene replacement.  相似文献   
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