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51.
Robert D. Dorn 《Brittonia》1998,50(2):193-210
Salix section Longifoliae occurs from Alaska to Guatemala and from the Atlantic to the Pacific. Nine taxa are here accepted as five species with one of the species including two subspecies and four varieties. the holotype of Salix taxifolia Humb., Bonpl. & Kunth represents the same taxon as the lectotype of Salix microphylla Schltdl. & Cham. Material recently called S. taxifolia is given a new name. Salix exilifolia Dorn. The name Salix fluviatilis Nutt is considered to be synonymous with S. melanopsis Nutt. One new variety is described and two new combinations are made under Salix exigua Nutt. 相似文献
52.
Yuanqing Tang Sergio Wittlin Susan A. Charman Jacques Chollet Francis C.K. Chiu Julia Morizzi Lisa M. Johnson Josefina Santo Tomas Christian Scheurer Chistopher Snyder Lin Zhou Yuxiang Dong William N. Charman Hugues Matile Heinrich Urwyler Arnulf Dorn Jonathan L. Vennerstrom 《Bioorganic & medicinal chemistry letters》2010,20(2):563-566
Thirty-three N-acyl 1,2,4-dispiro trioxolanes (secondary ozonides) were synthesized. For these ozonides, weak base functional groups were not required for high antimalarial potency against Plasmodium falciparum in vitro, but were necessary for high antimalarial efficacy in Plasmodium berghei-infected mice. A wide range of Log P/DpH 7.4 values were tolerated, although more lipophilic ozonides tended to be less metabolically stable. 相似文献
53.
Apple volatiles emitted at early phenological stages are little investigated, although they may influence behavior of early‐season pests. The apple blossom weevil Anthonomus pomorum is a herbivore pest of orchards in Europe. It colonizes apple trees in early season and oviposits into developing flower buds, often leading to economic damage. Using in situ radial diffusive sampling and thermal desorption, followed by GC/MS analysis, headspace volatiles from apple twigs with flower buds at three early phenological tree stages were identified and quantified. The volatile blend consisted of 13 compounds for the first, and increased to 15 compounds for the third phenological stage sampled. These blends included benzenoids, terpenes, and derivatives of fatty acids. A recombined synthetic blend served as the odor source in a still‐air dual‐choice olfactometer bioassay, in which individual male and female weevils were tested. Results from this behavioral test document an attraction of both sexes to odors of their host plant, suggesting that apple volatiles emitted in early season serve as olfactory cues for host location of A. pomorum in the field. 相似文献
54.
Dorn Watthanakulpanich Jitra Waikagul Wanna Maipanich Supaporn Nuamtanong Surapol Sanguankiat Somchit Pubampen Rangson Praevanit Srisuchat Mongkhonmu Yukifumi Nawa 《The Korean journal of parasitology》2010,48(3):225-229
The aim of this study is to clarify the clinical features of Haplorchis taichui infection in humans in Nan Province, Thailand, and to correlate the clinical features with irritable bowel syndrome (IBS)-like symptoms. In this study area, only H. taichui, but neither other minute intestinal flukes nor small liver flukes were endemic. The degree of infection was determined by fecal egg counts and also by collecting adult worms after deworming. The signs and symptoms of individual patients together with their hematological and biochemical laboratory data were gathered to evaluate the relationship between the clinical features and the severity of infection. Special emphasis was made to elucidate the possible similarities of the clinical features of H. taichui infection and IBS-like symptoms. The results showed useful clinical information and the significant (> 50%) proportion of haplorchiasis patients complained of abdominal pain, lassitude, and flatulence, which were the important diagnostic symptoms of IBS. This study has reported a possible link between H. taichui and IBS, and H. taichui might probably play a role in the etiology of these IBS-like symptoms. 相似文献
55.
Background
In species with single locus complementary sex determination (sl-CSD), the sex of individuals depends on their genotype at one single locus with multiple alleles. Haploid individuals are always males. Diploid individuals are females when heterozygous, but males when homozygous at the sex-determining locus. Diploid males are typically unviable or effectively sterile, hence imposing a genetic load on populations. Diploid males are produced from matings of partners that share an allele at the sex-determining locus. The lower the allelic diversity at the sex-determining locus, the more diploid males are produced, ultimately impairing the growth of populations and jeopardizing their persistence. The gregarious endoparasitoid wasp Cotesia glomerata is one of only two known species with sl-CSD and fertile diploid males. 相似文献56.
van Beers JJ Raijmakers R Alexander LE Stammen-Vogelzangs J Lokate AM Heck AJ Schasfoort RB Pruijn GJ 《Arthritis research & therapy》2010,12(6):R219
Introduction
Rheumatoid arthritis (RA) frequently involves the loss of tolerance to citrullinated antigens, which may play a role in pathogenicity. Citrullinated fibrinogen is commonly found in inflamed synovial tissue and is a frequent target of autoantibodies in RA patients. To obtain insight into the B-cell response to citrullinated fibrinogen in RA, its autoepitopes were systematically mapped using a new methodology. 相似文献57.
Programmed cell elimination is an important pathological mediator of disease. Multiple pathways to programmed cell death have been delineated, including apoptosis, autophagy and programmed necrosis. Cross-talk between the signaling pathways mediating each process has made it difficult to define specific mechanisms of in vivo programmed cell death. For this reason, many “apoptotic” diseases may involve other death signaling pathways. Recent advances in genetic complementation using mouse knockout models are helping to dissect apoptotic and necrotic cell death in different pathological states. The current state of research in this area is reviewed, focusing upon new findings describing the role of programmed necrosis induced by the mitochondrial permeability transition in mouse models of heart failure and diabetes.Key words: apoptosis, necrosis, mitochondrial permeability transition pore 相似文献
58.
Anne S. Jürgens Mateusz Kolanczyk Dietrich C. C. Moebest Tomasz Zemojtel Urs Lichtenauer Marlena Duchniewicz Melanie P. Gantert Jochen Hecht Uwe Hattenhorst Stefan Burdach Annette Dorn Mark P. Kamps Felix Beuschlein Daniel Räpple Jürgen S. Scheele 《In vitro cellular & developmental biology. Animal》2009,45(5-6):252-263
Experimentation with PBX1 knockout mice has shown that PBX1 is necessary for early embryogenesis. Despite broad insight into PBX1 function, little is known about the underlying target gene regulation. Utilizing the Cre–loxP system, we targeted a functionally important part of the homeodomain of PBX1 through homozygous deletion of exon-6 and flanking intronic regions leading to exon 7 skipping in embryonic stem (ES) cells. We induced in vitro differentiation of wild-type and PBX1 mutant ES cells by aggregation and retinoic acid (RA) treatment and compared their profiles of gene expression at the ninth day post-reattachment to adhesive media. Our results indicate that PBX1 interactions with HOX proteins and DNA are dispensable for RA-induced ability of ES to express neural genes and point to a possible involvement of PBX1 in the regulation of imprinted genes. 相似文献
59.
60.
Tang Y Dong Y Wittlin S Charman SA Chollet J Chiu FC Charman WN Matile H Urwyler H Dorn A Bajpai S Wang X Padmanilayam M Karle JM Brun R Vennerstrom JL 《Bioorganic & medicinal chemistry letters》2007,17(5):1260-1265
Thirty weak base 1,2,4-dispiro trioxolanes (secondary ozonides) were synthesized. Amino amide trioxolanes had the best combination of antimalarial and biopharmaceutical properties. Guanidine, aminoxy, and amino acid trioxolanes had poor antimalarial activity. Lipophilic trioxolanes were less stable metabolically than their more polar counterparts. 相似文献