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81.
The misuse of anabolic androgenic steroids (AAS) seems to produce profound effects on the central nervous system, leading to aggressive behavior and increased sensitivity to other drugs of abuse. The present study addresses the effect on the enzymatic transformation, here called dynorphin converting enzyme-like activity. The formation of the mu/delta opioid peptide receptor-preferring Leu-enkephalin-Arg(6) from the kappa opioid peptide receptor-preferring dynorphin A was measured in rats treated with nandrolone decanoate. Significant variations in enzymatic transformation were observed in several brain regions. An altered receptor activation profile in these regions may be one contributory factor behind AAS-induced personality changes. 相似文献
82.
We describe Tischeria gouaniae sp. n. from the tropical forests of Belize. The new species is a leaf-miner of Gouania polygama (Rhamnaceae). Together with the related T. bifurcata Braun, it is among the most striking representatives of Tischeria. Both species possess a pseudognathos and very broad aedeagus fused with extremely long lateral processes of the juxta. The new species differs from T. bifurcata in the broadly rounded vinculum, spiny juxta, and slender apical processes of the aedeagus, and in its host plant. The external features and male genitalia of Tischeria gouaniae sp. n. are figured and described. A checklist and distribution map for all nine currently known Tischeria species from North and South America are given. Most American species are known from USA, but others are now known from tropical forest habitats of Central America, the Caribbean, and Guyana. Host-plants are known for five of the nine species reviewed here, belonging to four genera and two plant families (Fagaceae and Rhamnaceae). 相似文献
83.
Recharacterization of ancient DNA miscoding lesions: insights in the era of sequencing-by-synthesis 总被引:9,自引:1,他引:8
Gilbert MT Binladen J Miller W Wiuf C Willerslev E Poinar H Carlson JE Leebens-Mack JH Schuster SC 《Nucleic acids research》2007,35(1):1-10
Although ancient DNA (aDNA) miscoding lesions have been studied since the earliest days of the field, their nature remains a source of debate. A variety of conflicting hypotheses exist about which miscoding lesions constitute true aDNA damage as opposed to PCR polymerase amplification error. Furthermore, considerable disagreement and speculation exists on which specific damage events underlie observed miscoding lesions. The root of the problem is that it has previously been difficult to assemble sufficient data to test the hypotheses, and near-impossible to accurately determine the specific strand of origin of observed damage events. With the advent of emulsion-based clonal amplification (emPCR) and the sequencing-by-synthesis technology this has changed. In this paper we demonstrate how data produced on the Roche GS20 genome sequencer can determine miscoding lesion strands of origin, and subsequently be interpreted to enable characterization of the aDNA damage behind the observed phenotypes. Through comparative analyses on 390 965 bp of modern chloroplast and 131 474 bp of ancient woolly mammoth GS20 sequence data we conclusively demonstrate that in this sample at least, a permafrost preserved specimen, Type 2 (cytosine→thymine/guanine→adenine) miscoding lesions represent the overwhelming majority of damage-derived miscoding lesions. Additionally, we show that an as yet unidentified guanine→adenine analogue modification, not the conventionally argued cytosine→uracil deamination, underpins a significant proportion of Type 2 damage. How widespread these implications are for aDNA will become apparent as future studies analyse data recovered from a wider range of substrates. 相似文献
84.
Dennis Hasselquist ?rjan ?stman Jonas Waldenstr?m Staffan Bensch 《Journal of Ornithology》2007,148(4):401-409
We studied the prevalence and intensity of the haemosporidian blood parasite Haemoproteus payevskyi in great reed warblers at Lake Kvismaren (6 years) and Lake Segersj? (3 years) in Sweden. Based on microscopic inspection
of slides from 282 adult birds, 20.6% showed infection of H. payevskyi in circulating red blood cells in at least 1 year. For parasite prevalence, there was no difference between years, sex, and
age classes. However, parasite intensity was higher in females than in males, and this was most pronounced in 1-year-old birds.
Individuals scored to carry parasites in year
n
were more likely to show parasite infection year
n + 1 than birds scored to be parasite-free in year
n
. None of 99 juvenile birds examined at the breeding site in late summer, 4–9 weeks after hatching, showed infection of H. payevskyi. Parasite intensity in infected adult birds decreased in the course of the breeding season and no new or relapse infections
were observed during this period. Thus, our data imply that in the great reed warbler, a long-distance migrant to tropical
Africa, transmission of H. payevskyi occurs on wintering sites or at stopover sites during migration. 相似文献
85.
PrepMS: TOF MS data graphical preprocessing tool 总被引:1,自引:0,他引:1
Karpievitch YV Hill EG Smolka AJ Morris JS Coombes KR Baggerly KA Almeida JS 《Bioinformatics (Oxford, England)》2007,23(2):264-265
We introduce a simple-to-use graphical tool that enables researchers to easily prepare time-of-flight mass spectrometry data for analysis. For ease of use, the graphical executable provides default parameter settings, experimentally determined to work well in most situations. These values, if desired, can be changed by the user. PrepMS is a stand-alone application made freely available (open source), and is under the General Public License (GPL). Its graphical user interface, default parameter settings, and display plots allow PrepMS to be used effectively for data preprocessing, peak detection and visual data quality assessment. AVAILABILITY: Stand-alone executable files and Matlab toolbox are available for download at: http://sourceforge.net/projects/prepms 相似文献
86.
Identification of six putative human transporters with structural similarity to the drug transporter SLC22 family 总被引:2,自引:0,他引:2
The solute carrier family 22 (SLC22) is a large family of organic cation and anion transporters. These are transmembrane proteins expressed predominantly in kidneys and liver and mediate the uptake and excretion of environmental toxins, endogenous substances, and drugs from the body. Through a comprehensive database search we identified six human proteins not yet cloned or annotated in the reference sequence databases. Five of these belong to the SLC22 family, SLC22A20, SLC22A23, SLC22A24, SLC22A25, and SPNS3, and the sixth gene, SVOPL, is a paralog to the synaptic vesicle protein SVOP. We identified the orthologs for these genes in mouse and rat and additional homologous proteins and performed the first phylogenetic analysis on the entire SLC22 family in human, mouse, and rat. In addition, we performed a phylogenetic analysis which showed that SVOP and SV2A-C are, in a comparison with all vertebrate proteins, most similar to the SLC22 family. Finally, we performed a tissue localization study on 15 genes on a panel of 30 rat tissues using quantitative real-time polymerase chain reaction. 相似文献
87.
Jonas BA Varlakhanova N Hayakawa F Goodson M Privalsky ML 《Molecular endocrinology (Baltimore, Md.)》2007,21(8):1924-1939
88.
The two faces of the 15-lipoxygenase in atherosclerosis 总被引:1,自引:0,他引:1
Chronic inflammation plays a major role in atherogenesis and understanding the role of inflammation and its resolution will offer novel approaches to interfere with atherogenesis. The 15(S)-lipoxygenase (15-LOX) plays a janus-role in inflammation with pro-inflammatory and anti-inflammatory effects in cell cultures and primary cells and even opposite effects on atherosclerosis in two different animal species. There is evidence for a pro-atherosclerotic effect of 15-LOX including the direct contribution to LDL oxidation and to the recruitment of monocytes to the vessel wall, its role in angiotensin II mediated mechanisms and in vascular smooth muscle cell proliferation. In contrast to the pro-atherosclerotic effects of 15-LOX, there is also a broad line of evidence that 15-LOX metabolites of arachidonic and linoleic acid have anti-inflammatory effects. The 15-LOX arachidonic acid metabolite 15-HETE inhibits superoxide production and polymorphonuclear neutrophil (PMN) migration across cytokine-activated endothelium and can be further metabolized to the anti-inflammatory lipoxins. These promote vasorelaxation in the aorta and counteract the action of most other pro-inflammatory factors like leukotrienes and prostanoids. Anti-atherogenic properties are also reported for the linoleic acid oxidation product 13-HODE through inhibition of adhesion of several blood cells to the endothelium. Furthermore, there is evidence that 15-LOX is involved in the metabolism of the long-chain omega-3 fatty acid docosahexaenoic acid (DHA) leading to a family of anti-inflammatory resolvins and protectins. From these cell culture and animal studies the role of the 15-LOX in human atherosclerosis cannot be predicted. However, recent genetic studies characterized the 15-LOX haplotypes in Caucasians and discovered a functional polymorphism in the human 15-LOX promoter. This will now allow large studies to investigate an association of 15-LOX with coronary artery disease and to answer the question whether 15-LOX is pro- or anti-atherogenic in humans. 相似文献
89.
Spatial distribution patterns of plague hosts: point pattern analysis of the burrows of great gerbils in Kazakhstan 总被引:1,自引:0,他引:1 下载免费PDF全文
90.
Enzymatic degradation of lignin‐carbohydrate complexes (LCCs): Model studies using a fungal glucuronoyl esterase from Cerrena unicolor 下载免费PDF全文