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Group System (group + system)
Kinds of Group System Selected AbstractsFloristics and Plant Biogeography in ChinaJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 7 2008De-Zhu Li Abstract In 1998, a revolutionary system of angiosperm classification, the Angiosperm Phylogeny Group system was published. Meanwhile, another new system of classification of angiosperms, the eight-class system was proposed by C. Y. Wu and colleagues based on long term work on the flora of China. The Flora Reipublicae Popularis Sinicae project was initiated in 1959 and completed by 2004. It is the largest Flora so far completed in the world, including 31 228 species of vascular plants, or one-eighth of the global plant diversity. The English-language and updated Flora of China (FOC) is an international joint effort initiated in 1988 and accelerated in 1998. Up to now, 15 of the 24 volumes of the FOC have been published. Based on the floristic data, the composition, characteristics, floristic divisions and affinities of the flora of China have been studied by Wu and colleagues since 1965. In the past 10 years, analyses of the available floristic data have been very productive. The East Asiatic Floristic Kingdom was proposed in 1998. All 346 families of angiosperms in China, according to the eight-class system of classification, were comprehensively discussed by using knowledge of current and historical distribution of seed plants in the world, together with some morphological and molecular data. A scheme of distribution patterns or areal-types of families and genera of seed plants in China was modified and elucidated, together with a proposed scheme of areal-types of the world. Molecular phylogenetic and biogeographical studies of angiosperms in China in the past 10 years also witnessed a progressive development. Integration of morphological and molecular data and fossil evidence revealed some significant results. Eastern Asia, which used to be regarded as an important center of survival during the ice age, is likely an important center of diversification of angiosperms. [source] Rural-Urban Differences in Health Risks, Resource Use and Expenditures Within Three State Medicaid Programs: Implications for Medicaid Managed CareTHE JOURNAL OF RURAL HEALTH, Issue 1 2002Janet M. Bronstein Ph.D. This study uses Medicaid claims data for income-eligible enrollees in California, Georgia and Mississippi to compare expenditures, resource usage and health risks between residents of rural and urban areas of the states. Resource use is measured using the Resource Based Relative Value Scale (RBRVS) system for professional services, hospital days and outpatient facility visits; it also is valued at private insurance reimbursement rates for the states. Health risks are measured using the diagnosis-based Adjusted Clinical Group system. Resource use is compared on a risk-adjusted basis with the use of urban Medicaid enrollees as the benchmark. We find that actual expenditures for rural care users are lower than for urban care users. However, because the proportion of Medicaid enrollees who use care is higher in rural than in urban areas in all three states, expenditures per rural enrollee are not consistently lower. Case mix is more resource intensive for rural compared to urban residents in all three states. Although resource usage is not systematically lower owerall for rural enrollees, on a risk-adjusted basis they tend to use less hospital resources than urban enrollees. Capitation rates based on historical per enrollee expenditures would not appear to under-reimburse managed care organizations for the care of rural as opposed to urban residents in the study states. [source] Improving blood donor screening by nucleic acid technology (NAT)ISBT SCIENCE SERIES: THE INTERNATIONAL JOURNAL OF INTRACELLULAR TRANSPORT, Issue n1 2010M. Schmidt The description of the ABO blood group system by Landsteiner and coworkers marked a sea change in making blood transfusions feasible and safe for a broad range of indications. Nevertheless, with an increase in blood transfusions, side-effects such as transfusion-transmitted infections (TTIs) became more and more important. A major challenge in transfusion medicine was (and is) to develop screening assays with maximum analytical sensitivity and analytical specificity to reduce the diagnostic window period as much as possible. Until the late 1990s, blood screening for TTIs depended entirely on serological assays. Except for HBV, where the virus can be detected using HBs-antigen assays, tests for the detection of other TTIs relied almost exclusively on antibody detection. These tests, however, are associated with a relatively long diagnostic window period because they detect the response of the immune system to an infection. [source] A Newly Recognized Blood Group in Domestic Shorthair Cats: The Mik Red Cell AntigenJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 2 2007Nicole M. Weinstein Background:Naturally occurring alloantibodies produced against A and B red cell antigens in cats can cause acute hemolytic transfusion reactions. Blood incompatibilities, unrelated to the AB blood group system, have also been suspected after blood transfusions through routine crossmatch testing or as a result of hemolytic transfusion reactions. Hypothesis:Incompatible crossmatch results among AB compatible cats signify the presence of a naturally occurring alloantibody against a newly identified blood antigen in a group of previously never transfused blood donor cats. The associated alloantibody is clinically important based upon a hemolytic transfusion reaction after inadvertent transfusion of red cells expressing this red cell antigen in a feline renal transplant recipient that lacks this red cell antigen. Methods: Blood donor and nonblood donor cats were evaluated for the presence of auto-and alloantibodies using direct antiglobulin and crossmatch tests, respectively, and were blood typed for AB blood group status. Both standard tube and novel gel column techniques were used. Results: Plasma from 3 of 65 cats and 1 feline renal transplant recipient caused incompatible crossmatch test results with AB compatible erythrocytes indicating these cats formed an alloantibody against a red cell antigen they lack, termed Mik. The 3 donors and the renal transplant recipient were crossmatch-compatible with one another. Tube and gel column crossmatch test results were similar. Conclusions and Clinical Importance: The absence of this novel Mik red cell antigen can be associated with naturally occurring anti- Mik alloantibodies and can elicit an acute hemolytic transfusion reaction after an AB-matched blood transfusion. [source] Isolation of a porcine UDP-GalNAc transferase cDNA mapping to the region of the blood group EAA locus on pig chromosome 1ANIMAL GENETICS, Issue 3 2001E. Meijerink In our studies of the genes constituting the porcine A0 blood group system, we have characterized a cDNA, encoding an ,(1,3)N-acetylgalactosaminyltransferase, that putatively represents the blood group A transferase gene. The cDNA has a 1095-bp open reading frame and shares 76.9% nucleotide and 66.7% amino acid identity with the human ABO gene. Using a somatic cell hybrid panel, the cDNA was assigned to the q arm of pig chromosome 1, in the region of the erythrocyte antigen A locus (EAA), which represents the porcine blood group A transferase gene. The RNA corresponding to our cDNA was expressed in the small intestinal mucosae of pigs possessing EAA activity, whereas expression was absent in animals lacking this blood group antigen. The UDP-N-acetylgalactosamine (UDP-GalNAc) transferase activity of the gene product, expressed in Chinese hamster ovary (CHO) cells, was specific for the acceptor fucosyl- ,(1,2)galactopyranoside; the enzyme did not use phenyl- , - D -galactopyranoside (phenyl- , -D-Gal) as an acceptor. Because the ,(1,3)GalNAc transferase gene product requires an ,(1,2)fucosylated acceptor for UDP-GalNAc transferase activity, the ,(1,2)fucosyltransferase gene product is necessary for the functioning of the ,(1,3)GalNAc transferase gene product. This mechanism underlies the epistatic effect of the porcine S locus on expression of the blood group A antigen. Abbreviations: CDS: coding sequence; CHO: Chinese Hamster Ovary; EAA: erythrocyte antigen A; FCS: foetal calf serum; Fuc,(1,2)Gal: fucosyl- ,(1,2)galactopyranoside; Gal: galactopyranoside; GGTA1: Gal,(1,3)Gal transferase; PCR: polymerase chain reaction; phenyl- , -D-Gal: phenyl- , - D -galactopyranoside; R: Gal,1-4Glc,1-1Cer; UDP-GalNAc: uridine diphosphate N-acetylgalactosamine [source] Sequence variation at the human ABO locusANNALS OF HUMAN GENETICS, Issue 1 2002S. P. YIP The ABO blood group is the most important blood group system in transfusion medicine. Since the ABO gene was cloned and the molecular basis of the three major alleles delineated about 10 years ago, the gene has increasingly been examined by a variety of DNA-based genotyping methods and analysed in detail by DNA sequencing. A few coherent observations emerge from these studies. First, there is extensive sequence heterogeneity underlying the major ABO alleles that produce normal blood groups A, B, AB and O when in correct combination with other alleles. Second, there is also extensive heterogeneity underlying the molecular basis of various alleles producing ABO subgroups such as A2, Ax and B3. There are over 70 ABO alleles reported to date and these alleles highlight the extensive sequence variation in the coding region of the gene. A unifying system of nomenclature is proposed to name these alleles. Third, extensive sequence variation is also found in the non-coding region of the gene, including variation in minisatellite repeats in the 5, untranslated region (UTR), 21 single nucleotide polymorphisms (SNPs) in intron 6 and one SNP in the 3, UTR. The haplotypes of these variations reveal a specific relationship with the major ABO alleles. Fourth, excluding the common alleles, about half of the remaining alleles are due to new mutations and the other half can better be explained by intragenic recombination (both crossover and gene conversion) between common alleles. In particular, the recombination sites in hybrid alleles can be quite precisely defined through haplotype analysis of the SNPs in intron 6. This indicates that recombination is equally as important as point mutations in generating the genetic diversity of the ABO locus. Finally, a large number of ABO genotyping methods are available and are based on restriction analysis, allele specific amplification, mutation screening techniques or their combinations. [source] A male bovine linkage map for the ADR granddaughter designJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 5 2000H. Thomsen Summary The aim of this paper is to present the construction of a male genetic linkage map as a result of the bovine genome mapping project, which is a common effort of the German cattle breeding federation (ADR), four animal breeding institutes, three blood group laboratories and two animal data and breeding value evaluation centres. In total 20 grandsires with 1074 sires were provided from the German cattle population as reference families, 16 of these paternal half-sib groups are German Holstein families (DH), three are German Simmental (ST) families, and one is a Brown Swiss family (BS). Of 265 markers included in the linkage map, 248 were microsatellite markers, five were bovine blood group systems, eight SSCP markers and four proteins and enzymes. More than 239 000 genotypes resulted from typing the offspring for the respective markers and these were used for the construction of the map. On average 478 informative meioses were provided from each marker of the map. The summarized map length over all chromosomes was 3135.1 cM with an average interval size of 13.34 cM. About 17, 35.7 and 79.1% of the map intervals showed a maximum genetic distance between the adjacent markers of 5, 10 and 20 cM, respectively. The number of loci ranged from two (pseudoautosomal region of the sex chromosome, BTAY) to 15 (BTA23) with an average of 8.8 markers per chromosome. Comparing the length of the chromosomes shows variation from 49.6 cM for BTA26 to 190.5 cM for BTA1 with a mean of 107.7 cM for all autosomes of the genetic linkage map. It was possible to identify chromosomal discrepancies in locus order and map intervals by comparison with other published maps. The map provided sufficient marker density to serve as a useful tool for a scan of segregating quantitative trait loci. Zusammenfassung Im vorliegenden Artikel wird die Erstellung der genetischen Markerkarten für das Rindergenom im Rahmen des Genomanalyseprojektes der Arbeitsgemeinschaft Deutscher Rinderzüchter (ADR) vorgestellt. Auf der Basis des ,Granddaughter Designs' wurde ein Familienmaterial bestehend aus 20 väterlichen Halbgeschwistergruppen mit 1074 Söhnen für die Typisierung mit genetischen Markern bereitgestellt. Insgesamt 16 dieser paternalen Halbgeschwisterfamilien lassen sich der Rasse Deutsche Holsteins zuordnen, drei Familien entstammen der Rasse Deutsches Fleckvieh, und eine Familie gehört der Rasse Deutsches Braunvieh an. Dabei variiert die Anzahl der Söhne von 19,128 pro Vater. Für die Typisierung wurden 248 Mikrosatellitenmarker aus bereits publizierten Karten ausgewählt. Zusätzlich konnten 8 SSCP-und RFLP Marker, 5 Blutgruppensysteme und 4 Proteinmarker zur Entwicklung der genetischen Karte herangezogen werden. Die Anzahl der Marker variierte von 2 (pseudoautosomaler Bereich des Geschlechtschromosoms) bis 15 (Chromosom 23), wobei durchschnittlich 8.8 genetische Marker pro Chromosom typisiert wurden. Im Durchschnitt lieferten die genetischen Marker 478 informative Meiosen pro Marker. Alle Typisierungsergebnisse wurden in die Kieler Markerdatenbank übertragen und auf etwaige Fehler geprüft. Als Ergebnis konnten die genetischen Karten für alle 29 Autosomen und den pseudoautosomalen Bereich des Geschlechtschromosoms erstellt werden. Dabei wurde ein Bereich von 3135.1 cM des Rindergenoms abgedeckt, wobei die Länge des durchschnittlichen Markerintervalls 13.34 cM beträgt. Die Längen der Chromosomen zeigten eine Variation von 49.6 cM für Chromosom 26 bis zu 190.5 cM für Chromosom 1. Aufgrund der Anzahl informativer Meiosen und der Markerdichte bildet diese genetische Markerkarte in gutes Instrument für eine genomweite Suche nach segregierenden Genorten, die für die Variation von quantitativen Merkmalen verantwortlich sind. [source] Canine Dal Blood Type: A Red Cell Antigen Lacking in Some DalmatiansJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 2 2007Marie-Claude Blais Background:Based upon alloantibodies produced after sensitizing dogs with transfused blood, more than a dozen blood group systems have been recognized thus far, and some have been classified as dog erythrocyte antigens (DEA). Hypothesis:A new canine red cell antigen was suspected, based on the development of specific alloantibodies in a Dalmatian previously sensitized by blood transfusions. Animals:Twenty-six Dalmatians (including 1 Dalmatian in need of blood compatibility studies); 55 canine blood donors. Methods:Serologic tests, including blood typing, crossmatching, and direct Coombs' test were performed by standard tube techniques and a novel gel column technology adapted from human blood banking. Results:By day 40 after transfusion of an anemic Dalmatian, all major crossmatch tests to 55 non-Dalmatian dogs were incompatible. The 2 initial donors, who were compatible before transfusion, were also now incompatible, suggesting the development of an alloantibody to a common red cell antigen. No siblings were available, but 4 of 25 unrelated Dalmatians were crossmatch compatible, suggesting that they were missing the same red cell antigen. The patient was blood typed DEA 1.1, 3, 4, and 5 positive, but DEA 7 negative. Further blood typing and crossmatching results did not support an association to any of these known blood types. The alloantibodies produced were determined to be of the immunoglobulin G class. Conclusions and Clinical Importance: Based upon the identification of an acquired alloantibody in a Dalmatian, a presumably new common blood type named Dal was identified. Dalmatians lacking the Dal antigen are likely at risk of delayed and acute hemolytic transfusion reactions. [source] Peer Group Formation in an Adverse Selection ModelTHE ECONOMIC JOURNAL, Issue 465 2000Beatriz Armendariz De Aghion This paper develops an adverse selection model where peer group systems are shown to trigger lower interest rates and remove credit rationing in the case where borrowers are uninformed about their potential partners and ex post state verification (or auditing) by banks is costly. Peer group formation reduces interest rates due to a ,collateral effect', namely, cross subsidisation amongst borrowers acts as collateral behind a loan. By uncovering such a collateral effect, this paper shows that peer group systems can be viewed as an effective risk pooling mechanism, and thus enhance efficiency, not just in the full information set up. [source] Tissue distribution of histo-blood group antigens.APMIS, Issue 1 2000Vibeke Ravn The introduction of immunohistochemical techniques and monoclonal antibodies to specific carbohydrate epitopes has made it possible to study in detail the tissue distribution of histo-blood group antigens and related carbohydrate structures. The present paper summarizes the available data concerning the histological distribution of histo-blood group antigens and their precursor structures in normal human tissues. Studies performed have concentrated on carbohydrate antigens related to the ABO, Lewis, and TTn blood group systems, i.e. histo-blood group antigens carried by type 1, 2, and 3 chain carrier carbohydrate chains. Histo-blood group antigens are found in most epithelial tissues. Meanwhile, several factors influence the type, the amount, and the histological distribution of histo-blood group antigens, i.e. the ABO, Lewis, and saliva-secretor type of the individual, and the cell-and tissue type. Oligosaccharides with blood-group specificity are synthesized by the stepwise action of specific gene-encoded glycosyltransferases. In general, this stepwise synthesis of histo-blood group antigens correlates with cellular differentiation. The H and the Se genes both encode an ,1,2fucosyltransferase, which is responsible for the synthesis of blood group antigen H from precursor disaccharides. A new model for the participation of the Se/H-gene-encoded glycosyl transferases in synthesis of terminal histo-blood group antigens in human tissues is proposed; the type and degree of differentiation rather than the embryologic origin determines whether it is the H or the Se gene-encoded transferases that influence expression of terminal histo-blood group antigens in tissues. 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