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991.
Millar M 《Journal of behavioral medicine》2005,28(5):425-432
This study examined the impact of perceived stress on responses to messages that encouraged the performance of health promotion
and disease detection behaviors. It was hypothesized that increases in perceived stress would be associated with decreased
processing of messages encouraging disease detection behaviors, and that increases in perceived stress would not effect the
processing of messages encouraging health promotion behaviors. To test these hypotheses participants completed a perceived
stress measure and then read a message that encouraged the performance of either a health promotion or a disease detection
behavior. Then the participants were asked to indicate their agreement with the message and to attempt to recall the message.
The results indicated that participants experiencing higher levels of perceived stress spent less time reading and recalled
less of the messages about detection behaviors than of the messages about promotion behaviors. When participants were experiencing
lower levels of perceived stress these differences disappeared.
相似文献
相似文献
992.
993.
Rice as a model for centromere and heterochromatin research 总被引:2,自引:0,他引:2
Rice (Oryza sativa) has become an important model plant species in numerous research projects involving genome, molecular and evolutionary biology.
In this review we describe the reasons why rice provides an excellent model system for centromere and heterochromatin research.
In most multicellular eukaryotes, centromeres and heterochromatic domains contain long arrays of repetitive DNA elements that
are recalcitrant to DNA sequencing. In contrast, three rice centromeres and the majority of the cytologically defined heterochromatin
in the rice genome have been sequenced to high quality, providing an unparalleled resource compared to other model multicellular
eukaryotes. Most importantly, active genes have been discovered in the functional domains of several rice centromeres. The
centromeric genes and sequence resources provide an unprecedented opportunity to study function and evolution of centromeres
and centromere-associated genes. 相似文献
994.
995.
Laura Cerni Giancarlo Biancotto Adriana Tondolo Paolo Bogoni 《Food and Agricultural Immunology》1998,10(4):307-315
A fast and simple extraction procedure was developed for simultaneous determination in bovine liver of two veterinary drugs, widely used as growth promoters in meat production: dexamethasone (a synthetic corticosteroid drug) and clenbuterol (a beta2‐adrenergic agonist drug). Liver samples were extracted by acetonitrile, without any clean‐up step. Two different ELISAs, specific for the two classes of drugs, were used to determine the residue concentration in the extracts. The intra‐ and inter‐extraction variability was determined at different concentrations: the intra‐extraction coefficients of variation (CVs) were between 2.5 and 17.7% for dexamethasone and between 0.9 and 9.8% for clenbuterol; the inter‐extraction CVs were between 2.0 and 16.8% for dexamethasone and between 0.5 and 10.8% for clenbuterol. Recovery ranged from 92 to 154% for dexamethasone and from 78 to 105% for clenbuterol. The limit of detection was 1.43 ng g?1 and 0.43 ng g?1, respectively. The limit of quantification for dexamethasone was 2.09 ng g?1 and for clenbuterol was 0.72 ng g?1. The combination of the new extraction procedure with an ELISA detection permitted the rapid semi‐quantitative determination of both dexamethasone at its maximum residue level (MRL: 2.5 ng g?1 in liver tissue), and clenbuterol at low concentration level. 相似文献
996.
Ana J. Alarcos Jorge A. Etchegoin Florencia Cremonte 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2008,53(4):365-368
In this paper Steringotrema microacetabularis (Suriano et Martorelli, 1983) is redescribed and transferred to Bacciger Nicoll, 1924 in the Faustulidae Poche, 1926 based on newly collected material from the type-host, Paralichthys orbignyanus Valenciennes, 1839 and the type-locality, Mar Chiquita coastal lagoon, Buenos Aires Province, Argentina. A careful re-examination
of the new specimens shows that some anatomical characteristics were ignored or incompletely described by the previous authors
and they are included herein. The species is tentatively transferred to Bacciger with which it appears to have closest affinity. Despite the anatomical differences detailed in this paper, confirmation of
this proposal must await further work, including molecular studies. 相似文献
997.
Watkins LH Sahakian BJ Robertson MM Veale DM Rogers RD Pickard KM Aitken MR Robbins TW 《Psychological medicine》2005,35(4):571-582
BACKGROUND: Cognitive performance was compared in the genetically and neurobiologically related disorders of Tourette's syndrome (TS) and obsessive-compulsive disorder (OCD), in three domains of executive function: planning, decision-making and inhibitory response control. METHOD: Twenty TS patients, twenty OCD patients and a group of age- and IQ-matched normal controls completed psychometric and computerized cognitive tests and psychiatric rating scales. The cognitive tests were well-characterized in terms of their sensitivity to other fronto-striatal disorders, and included pattern and spatial recognition memory, attentional set-shifting, and a Go/No-go set-shifting task, planning, and decision-making. RESULTS: Compared to controls, OCD patients showed selective deficits in pattern recognition memory and slower responding in both pattern and spatial recognition, impaired extra-dimensional shifting on the set-shifting test and impaired reversal of response set on the Go/No-go test. In contrast, TS patients were impaired in spatial recognition memory, extra-dimensional set-shifting, and decision-making. Neither group was impaired in planning. Direct comparisons between the TS and OCD groups revealed significantly different greater deficits for recognition memory latency and Go/No-go reversal for the OCD group, and quality of decision-making for the TS group. CONCLUSIONS: TS and OCD show both differences (recognition memory, decision-making) and similarities (set-shifting) in selective profiles of cognitive function. Specific set-shifting deficits in the OCD group contrasted with their intact performance on other tests of executive function, such as planning and decision-making, and suggested only limited involvement of frontal lobe dysfunction, possibly consistent with OCD symptomatology. 相似文献
998.
Charles R. Bursey Stephen R. Goldberg Fred Kraus 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2007,52(2):142-145
Falcaustra papuensis sp. nov. (Ascaridida, Kathlaniidae) from the large intestine of Sphenomorphus simus (Squamata, Sciencidae) is described and illustrated. Falcaustra papuensis represents the 4th Australo-Papuan species assigned to this genus and is distinguished from other Australo-Papuan species
by the distribution pattern of caudal papillae (6 precloacal, 6 adcloacal, 8 postcloacal, and 1 median), length of spicules
(561–714 μm) and presence of a pseudosucker. Sphenomorphus simus was found to harbor 2 additional species of nematodes, Meteterakis crombiei and Oswaldocruzia bakeri. Sphenomorphus simus represents a new host record for each of these nematode species. 相似文献
999.
Anthony J Sharp Paul E Polak Vittoria Simonini Shao X Lin Jill C Richardson Ernesto R Bongarzone Douglas L Feinstein 《Journal of neuroinflammation》2008,5(1):33
Background
The purinergic receptor P2x7 is expressed on myeloid cells as well as on CNS glial cells, and P2x7 activation has been shown to increase both glial and T-cell activation. These properties suggest a role in the development of autoimmune disease including multiple sclerosis. 相似文献1000.
Mannelli A Nebbia P Tramuta C Grego E Tomassone L Ainardi R Venturini L De Meneghi D Meneguz PG 《Journal of medical entomology》2005,42(2):168-175
Birds belonging to 59 species (n = 1,206) were live captured in Piemonte, northwestern Italy, in 2001. Ixodes ricinus (L.) larvae were collected from 59 birds belonging to nine species, and nymphs were recovered on 79 birds belonging to 10 species. Eurasian blackbirds, Turdus merula L., had significantly higher levels of infestation by ticks than other passerine species. Larval I. ricinus of blackbirds peaked in summer, when prevalence was 39% (95% confidence interval 24.2-55.5) and mean number of ticks per host was 3.3 (1.6-7.2), whereas nymphs peaked in spring, when prevalence was 72.2% (54.8-85.8) and mean number of ticks per host was 6.9 (4.4-10.7). Immature I. ricinus were coincidentally aggregated on blackbirds, with 15 blackbirds feeding 67.4% of nymphs and 40.3% of larvae, and coinfestation by both stages was relatively high in summer: Kappa = 0.64 (0.40-0.88). Borrelia burgdorferi sensu lato was identified by polymerase chain reaction (PCR) in 58.3% (35.9-78.5) of larvae with engorgement ratio > or = 3 that were collected from blackbirds. Larvae that were collected from other passerine species gave negative PCR results. Sixteen of 21 PCR-positive samples belonged to B. garinii (76.2%), and five (23.8%) were Borrelia valaisiana. Results of this study suggest that blackbirds play an important role as hosts for immature I. ricinus and as reservoir of Borrelia garinii in northwestern Italy. 相似文献