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981.
982.
Physiological and transcriptional characterization of Escherichia coli strains lacking interconversion of phosphoenolpyruvate and pyruvate when glucose and acetate are coutilized 下载免费PDF全文
983.
Tajvur P Saber CT Ng Guillaume Renard Bernadette M Lynch Eliza Pontifex Ceara AE Walsh Alexia Grier Marian Molloy Barry Bresnihan Oliver FitzGerald Ursula Fearon Douglas J Veale 《Arthritis research & therapy》2010,12(3):1-6
Introduction
Since remission is now possible in psoriatic arthritis (PsA) we wished to examine remission rates in PsA patients following anti tumour necrosis factor alpha (TNFα) therapy and to examine possible predictors of response.Methods
Analysis of a prospective patient cohort attending a biologic clinic, between November 2004 and March 2008, was performed prior to commencing therapy and at regular intervals. Baseline clinical characteristics including demographics, previous disease-modifying antirheumatic drug (DMARD) response, tender and swollen joint counts, early morning stiffness, pain visual analogue score, patient global assessment, C reactive protein (CRP) and health assessment questionnaire (HAQ) were collected.Results
A total of 473 patients (152 PsA; 321 rheumatoid arthritis (RA)) were analyzed. At 12 months remission, defined according to the disease activity score using 28 joint count and CRP (DAS28-CRP), was achieved in 58% of PsA patients compared to 44% of RA patients, significant improvement in outcome measures were noted in both groups (P < 0.05). Analysis of a subgroup of PsA and RA patients matched for DAS28-CRP at baseline also showed higher numbers of PsA patients achieving remission. Linear regression analysis identified the HAQ at baseline as the best predictor of remission in PsA patients (P < 0.001).Conclusions
DAS28 remission is possible in PsA patients at one year following anti-TNF therapy, at higher rates than in RA patients and is predicted by baseline HAQ. 相似文献984.
985.
Reduction of conjugal transfer efficiency by three restriction activities of Anabaena sp. strain PCC 7120. 总被引:7,自引:0,他引:7 下载免费PDF全文
J Elhai A Vepritskiy A M Muro-Pastor E Flores C P Wolk 《Journal of bacteriology》1997,179(6):1998-2005
The efficiency of conjugal transfer of plasmids from Escherichia coli to the cyanobacterium Anabaena sp. strain PCC 7120 was quantitated as a function of the number of restriction sites for the restriction enzymes carried by the recipient. In addition to the previously recognized isoschizomers of AvaI and AvaII, PCC 7120 was found to possess an isoschizomer of AvaIII. Plasmids modified in E. coli with methylases that protect in vitro against restriction by the three enzymes were transferred with high efficiency, nearly independent of the number of restriction sites on the plasmid. Plasmids left unprotected against one of the three restriction enzymes were transferred with lower efficiencies. For low numbers of sites, the efficiency of conjugal transfer decreased as an exponential function of the number of unprotected sites. The methods presented may be used to increase the efficiency of conjugal transfer into restriction-competent bacteria. 相似文献
986.
A comparative analysis on cranial ontogeny of South American fur seals (Otariidae: Arctocephalus) 下载免费PDF全文
Bárbara A. Tarnawski David Flores Guillermo Cassini Luis H. Cappozzo 《Zoological Journal of the Linnean Society》2015,173(1):249-269
We analysed the cranial ontogeny of male Arctocephalus australis (Zimmermann, 1783) (N = 116), Arctocephalus gazella (Peters, 1875) (N = 69), and Arctocephalus tropicalis (Gray, 1872) (N = 51) to study skull growth and its allometric patterns in the genus. We used 15 metric variables with bivariate and multivariate approaches to detect interspecific similarities and differences between growth trends, which we discussed in the context of phylogeny and life history. We found common trajectories in 20% of variables, detecting that the differences between adults were associated with size. We detected higher growth rates in A. gazella than in A. australis and A. tropicalis, which were associated with shape differences. Amongst the three species, A. tropicalis was morphologically intermediate, showing additional common trends with A. gazella and A. australis, and an intermediate position in the multivariate morphospace. Allometric patterns were also compared with growth trends described for Otaria byronia (Péron, 1816) and Mirounga leonina (Linnaeus, 1758). We detected positive allometry in Arctocephalus for the mastoid width (MW) but negative allometry in O. byronia and M. leonina. This could indicate that males of Arctocephalus exhibited a delayed development of MW. Finally, the presence of common growth trends for the skull length and the postorbital constriction could indicate a conservative pattern within otariids. © 2014 The Linnean Society of London 相似文献
987.
Parasites component community in wild population of Pterophyllum scalare Schultze, 1823 and Mesonauta acora Castelnau, 1855, cichlids from the Brazilian Amazon 下载免费PDF全文
W. M. Farias Pantoja L. Vargas Flores M. Tavares‐Dias 《Zeitschrift fur angewandte Ichthyologie》2015,31(6):1043-1048
The aim of the present study was to compare the component parasite communities of the Pterophyllum scalare and Mesonauta acora cichlids in the Amazon River system in northern Brazil. From September to December 2012, 42 specimens of P. scalare and 38 specimens of M. acora were captured using hand nets and gillnets in the Igarapé Fortaleza basin, a tributary of the Amazon River in the state of Amapá. Of the P. scalare specimens examined, 97.6% were parasitized by Ichthyophthirius multifiliis, Tripartiella sp., Trichodina nobilis, Gussevia spiralocirra, Posthodiplostomum sp., Capillaria pterophylli, Ichthyouris sp. and Gorytocephalus spectabilis. Similarly, all specimens of M. acora were parasitized by I. multifiliis, Tripartiella sp, T. nobilis, Sciadicleithrum joanae, Posthodiplostomum sp., Pseudoproleptus sp., Ichthyouris sp. and G. spectabilis. However, for both hosts the dominance was of I. multifiliis and with an overdispersion of parasites. Parasite communities of P. scalare and M. acora were similar and only Pseudoproleptus sp. and Posthodiplostomum sp. were larvae. Brillouin diversity, parasite species richness and evenness were higher for M. acora than for P. scalare, which presented a negative correlation of parasite abundance with body size. Both cichlid species had parasite communities characterized by low diversity and low species richness, with a predominance of ectoparasite species and greatest richness of helminth species, with a low abundance of endoparasites. This was the first study on the parasite diversity in wild P. scalare and M. acora. 相似文献
988.
989.
Benjamin Gilbert Andrew S. MacDougall Taku Kadoya Munemitsu Akasaka Joseph R. Bennett Eric M. Lind Habacuc Flores‐Moreno Jennifer Firn Yann Hautier Elizabeth T. Borer Eric W. Seabloom Peter B. Adler Elsa E. Cleland James B. Grace William Stanley Harpole Ellen H. Esch Joslin L. Moore Johannes Knops Rebecca McCulley Brent Mortensen Jonathan Bakker Philip A. Fay 《Global Ecology and Biogeography》2020,29(7):1177-1188
990.