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1.
Immunoprecipitation of NP-40 lysates of 125I-labeled lymph-node cells with different anti-H-2 sera and with anti-Qa-2 serum has shown that the BALB/cByA strain (H-2d, Qa-2-negative) expresses, besides H-2Ld, another molecule that is not detectable in the BALB/c-H-2dm2 strain. Electrophoresis in SDS polyacrylamide gels indicated that this molecule, provisionally designated Lq, has an apparent molecular weight of 41000 daltons, in contrast to approximately 49000 daltons for H-2Kd and H-2Ld, and 47000 daltons for H-2Dd molecules. The anti-Qa-2 serum precipitated from the Qa-2-positive strains BALB/cHeA but not from the Qa-2-negative strains BALB/cByA and BALB/c-H-2dm2 a protein that gave a very strong band corresponding to the molecular weight 41000 daltons in the gel electrophoresis. The biochemical characteristics of the Lq molecule are thus more similar to those of Qa-2 than of H-2 antigens. 相似文献
2.
Daris R. Swindler 《American journal of physical anthropology》1968,28(2):234-236
3.
Andreas H. Kottmann Gerhard H. A. Seemann H. Detlef Guessow Marleen H. Roos 《Immunogenetics》1986,23(6):396-400
An HLA-B44 cDNA clone was identified in a cDNA library constructed from an HLA-B44 homozygous cell line. The DNA sequence was determined and was found to contain the complete coding sequence but for (probably) the three N-terminal codons. Comparisons of the derived amino acid sequence with other HLA-A and -B locus amino acid sequences revealed four HLA-B44-specific substitutions including a new polymorphic site. Regions of strong sequence conservation for HLA-B-locus products were found at the nucleotide and amino acid levels. 相似文献
4.
Summary Two unrelated patients were found to be mosaic for an extra chromosome 9 (46,XX/47,XX,+9). The first patient showed a prominent nose, deep set eyes, carp shaped mouth and complex congenital cardiac anomalies. She died of congestive cardiac failure at the age of 10 days. The second patient, was a 7 1/2 year old female who had persistent alacrimia and mental retardation. 相似文献
5.
6.
Fossil ceboid evidence is reviewed with reference to the origins and affinities of the New World monkeys. This evidence indicates that the ceboids evolved from a North American primate of omomyid-like form. The events of continental drift apparently had little to do with the origin and dispersion of the New World monkeys and direct relationships to the Old World monkeys are not indicated. Three of the five extant New World monkey subfamilies are represented in late Miocene deposits of South America and it appears that evolutionary events leading to extant Ceboidea occurred within the South American continent. 相似文献
7.
Marleen Perseke Anja Golombek Martin Schlegel Torsten H. Struck 《Molecular phylogenetics and evolution》2013,66(3):898-905
Deuterostomia, one of the three major lineages of Bilateria, comprises many well-known animals such as vertebrates, sea squirts, sea stars and sea urchins. Whereas monophyly of Deuterostomia and several subtaxa is well supported, the relationships of these to each other and, hence, deuterostome relationships are still uncertain. To address these issues in deuterostome phylogeny we analyzed datasets comprising more than 300 complete deuterostome mitochondrial genomes. Based on sequence information, the results revealed support for several relationships such as a basal position of Xenoturbella within Deuterostomia or for taxa like Craniota or Ambulacraria, but yielded also problems in some taxa, e.g. Tunicata, Pterobranchia and Ophiuroidea, due to long-branch artifacts. However, within tunicates the relationships are well supported. Variation in the genetic code was also informative and, e.g., supported the taxon Ambulacraria including Pterobranchia. 相似文献
8.
Forest-to-rubber plantation conversion is an important land-use change in the tropical region, for which the impacts on soil carbon stocks have hardly been studied. In montane mainland southeast Asia, monoculture rubber plantations cover 1.5 million ha and the conversion from secondary forests to rubber plantations is predicted to cause a fourfold expansion by 2050. Our study, conducted in southern Yunnan province, China, aimed to quantify the changes in soil carbon stocks following the conversion from secondary forests to rubber plantations. We sampled 11 rubber plantations ranging in age from 5 to 46 years and seven secondary forest plots using a space-for-time substitution approach. We found that forest-to-rubber plantation conversion resulted in losses of soil carbon stocks by an average of 37.4±4.7 (SE) Mg C ha−1 in the entire 1.2-m depth over a time period of 46 years, which was equal to 19.3±2.7% of the initial soil carbon stocks in the secondary forests. This decline in soil carbon stocks was much larger than differences between published aboveground carbon stocks of rubber plantations and secondary forests, which range from a loss of 18 Mg C ha−1 to an increase of 8 Mg C ha−1. In the topsoil, carbon stocks declined exponentially with years since deforestation and reached a steady state at around 20 years. Although the IPCC tier 1 method assumes that soil carbon changes from forest-to-rubber plantation conversions are zero, our findings show that they need to be included to avoid errors in estimating overall ecosystem carbon fluxes. 相似文献
9.
Christopher I. Cazzonelli Marleen Vanstraelen Sibu Simon Kuide Yin Ashley Carron-Arthur Nazia Nisar Gauri Tarle Abby J. Cuttriss Iain R. Searle Eva Benkova Ulrike Mathesius Josette Masle Ji?í Friml Barry J. Pogson 《PloS one》2013,8(7)
Plant-specific PIN-formed (PIN) efflux transporters for the plant hormone auxin are required for tissue-specific directional auxin transport and cellular auxin homeostasis. The Arabidopsis PIN protein family has been shown to play important roles in developmental processes such as embryogenesis, organogenesis, vascular tissue differentiation, root meristem patterning and tropic growth. Here we analyzed roles of the less characterised Arabidopsis PIN6 auxin transporter. PIN6 is auxin-inducible and is expressed during multiple auxin–regulated developmental processes. Loss of pin6 function interfered with primary root growth and lateral root development. Misexpression of PIN6 affected auxin transport and interfered with auxin homeostasis in other growth processes such as shoot apical dominance, lateral root primordia development, adventitious root formation, root hair outgrowth and root waving. These changes in auxin-regulated growth correlated with a reduction in total auxin transport as well as with an altered activity of DR5-GUS auxin response reporter. Overall, the data indicate that PIN6 regulates auxin homeostasis during plant development. 相似文献
10.
Ping Wang Paul P.C.A. Menheere Arne Astrup Malene R. Andersen Marleen A. van Baak Thomas M. Larsen Susan Jebb Anthony Kafatos Andreas F.H. Pfeiffer J. Alfredo Martinez Teodora Handjieva‐Darlenska Petr Hlavaty Nathalie Viguerie Dominique Langin Wim H.M. Saris Edwin C.M. Mariman Diogenes consortium 《Obesity (Silver Spring, Md.)》2013,21(10):1997-2006