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The elevated plus-maze (EPM) is an anxiety model thought to assess different types of emotional states depending on whether or not the animals have been previously exposed to the test apparatus. Accordingly, benzodiazepine-treated rodents generally differ from controls in the first but not in the second EPM trial. Inbred Lewis and SHR rats of both sexes (N = 10) were submitted twice (test and retest) to the EPM with a 24 h interval between trials. Overall strain differences (Lewis < SHR) were observed in both males and females concerning anxiety-related measures (time spent and percent of entries in the open arms) regardless of previous maze experience. Moreover, prior exposure to the test apparatus produced an overall decrease in the approach towards the open arms in both strains and sexes. The fact that genetic differences did not diminish or disappear in the second trial, suggests that test and retest in the EPM are likely to share some common emotional components and that differences between naïve LEW and SHR rats are not similar to those observed between control and benzodiazepine-treated animals.  相似文献   
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Pervaporation proved to be one of the best methods to remove solvents out of a solvent producing Clostridium acetobutylicum culture. By using an ionic liquid (IL)-polydimethylsiloxane (PDMS) ultrafiltration membrane (pore size 60 nm), we could guarantee high stability and selectivity during all measurements carried out at 37°C. Overall solvent productivity of fermentation connected with continuous product removal by pervaporation was 2.34 g l−1 h−1. The supported ionic liquid membrane (SILM) was impregnated with 15 wt% of a novel ionic liquid (tetrapropylammonium tetracyano-borate) and 85 wt% of polydimethylsiloxane. Pervaporation, accomplished with the optimized SILM, led to stable and efficient removal of the solvents butan-1-ol and acetone out of a C. acetobutylicum culture. By pervaporation through SILM, we removed more butan-1-ol than C. acetobutylicum was able to produce. Therefore, we added an extra dose of butan-1-ol to run fermentation on limiting values where the bacteria would still be able to survive its lethal concentration (15.82 g/l). After pervaporation was switched off, the bacteria died from high concentration of butan-1-ol, which they produced.  相似文献   
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Caatinga Ethnobotany: Anthropogenic Landscape Modification and Useful Species in Brazil’s Semi-Arid Northeast This study explores the contribution of anthropogenic landscapes in providing useful botanical resources to a Caatinga community in Pernambuco, Brazil. Ethnobotanical data were collected through semi-structured interviews using the checklist-interview method and by means of a “field herbarium” of the most abundant species in the anthropogenic zones. We recorded 119 species distributed in 36 families, of which 79 were found to be useful. Forage was the most prominent use category, containing 84% of the citations, followed by medicinals (36.70%), foods (10.12%), and wood (8.86%). Herbaceous species predominated (63.29%), followed by shrubs (3.79%), sub-shrubs (21.51%), trees (8.86%), and creepers (2.53%). Trees exhibited a greater number of uses than other life-forms (p < 0.05). Significant differences in richness were found, with the highest richness of species (χ2 = 60.28, p < 0.05), genera (χ2 = 49.03, p < 0.05), and families (χ2 = 20.16, p < 0.05) appearing in the rainy season. We concluded that fodder use was the most important category in our anthropogenic research areas, accounting for a higher number of species, genera, and families. The next most important categories were medicinal, timber, and food plants, respectively.  相似文献   
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Studies undertaken in the Atlantic Coastal Forest have revealed a notable floristic heterogeneity within this vegetation type in NE Brazil. However, there is still a great need for detailed comparisons of the floristic relationships between the various forest types found there. This work presents an analysis of the floristic similarity (at the species level) of these forest as revealed by floristic surveys, with the aim of better understanding and defining this vegetation. Using a binary matrix, grouping, ordering, and TWINSPAN analysis were performed on 742 tree/shrub species listed in 35 different plant surveys. These tree/shrub species were divided by these analysis into two large floristic groups – ombrophilous and semideciduous. The semideciduous group was formed, in general, by forest areas located at altitudes above 700 m (montane forests), and could itself be divided into two subgroups. The first subgroup was located more inland (Pernambuco), while the second subgroup was located nearer the coast (within the states of Pernambuco and Ceará). The ombrophilous group was quite heterogeneous, but could also be divided into two floristic subgroups: i) lowland forests (below 100 m a.s.l) in the states of Pernambuco, Paraíba, and in two areas of Bahia, as well as some montane forests (in Pernambuco, between 640 and 900 m a.s.l.); ii) lowlands forests in the states of Alagoas and Bahia. This latter subgroup is the largest and best defined, and has the highest degree of internal similarity. Nonetheless, it can be further subdivided into two smaller classes, one in Alagoas and the other in Bahia State. The results of this study demonstrate that the concept of the Atlantic Coastal Forest could also include montane ombrophilous forests in Pernambuco State, as these forests form a single floristic unit together with lowland forests in that state. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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The behavioral characterization of rodent strains in different studies and laboratories can provide unreplicable results even when genotypes are kept constant and environmental control is maximized. In the present study, the influence of common laboratory environmental variables and their interaction with genotype on the results of behavioral tests of anxiety/emotionality were investigated. To this end, the inbred rat strains Lewis (LEW) and spontaneously hypertensive rats (SHR), which are known to differ for numerous emotionality-related behaviors, were tested in the open field (OF), elevated plus maze (EPM) and black/white box (BWB), while three environmental factors were systematically controlled and analyzed: (1) the experimenter handling the animal (familiar or unfamiliar); (2) the position of the home cage (top or bottom shelf of the rack) and (3) the behavioral state of the animal immediately before the test (arousal or rest). Experimenter familiarity did not alter the behavior of rats in the OF. Cage position, on the other hand, influenced the behavior in the OF and BWB, with rats housed in top cages appearing less anxious than those housed in the bottom. In the BWB (but not in the OF), these effects were genotype dependent. Finally, the behavioral state of the animals prior to testing altered the results of the EPM in a strain-dependent manner, with some anxiety-related genotypic differences being found only among rats that were aroused in their home cages. This study showed that common variations in the laboratory environment interact with genotype in behavioral tests of anxiety/emotionality. Recognizing and understanding such variations can help in the design of more effective experiments.  相似文献   
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Iz. de Haan 《Protoplasma》1935,22(1):395-404
Zusammenfassung PrÄparate der Innenepidermis der Zwiebelschuppen vonAllium cepa wurden 5 Minuten in eine NaNO3-Lösung (123 M. aeq.) gelegt. Sodann erfolgten Plasmolyse in einer 0,646 GM Rohrzuckerlösung und Deplasmolyse in einer 0,20 GM Rohrzuckerlösung. In dem Augenblick, da die mit NaNO3 behandelten PrÄparate in das Deplasmolytikum übertragen werden, erfolgt Kappenplasmolyse.Es zeigt sich, da\ diese Protoplasten eine geringe WasserpermeabilitÄt besitzen.Wird dasselbe mit einer Ca(NO3)2-Lösung (123 M. aeq.) ausgeführt, so erfolgt keine Kappenplasmolyse; die WasserpermeabilitÄt wird nicht beeinflu\t.Wird das NaNO3 (123 M. aeq.) dem Plasmolytikum sowie dem Deplasmolytikum zugefügt (wÄhrend man darauf achtet, da\ diese mit den oben angewandten 0,646 GM und 0,20 GM Rohrzuckerlösungen isotonisch bleiben), so erfolgt keine Kappenplasmolyse und die WasserpermeabilitÄt ist erhöht.Die morphologischen VerÄnderungen des Protoplasmas verschwinden wieder nach ca. 10 Stunden Aufenthalt in einer Rohrzuckerlösung.Schlie\lich werden die erhaltenen Resultate an der Hand der Literatur besprochen.

Die Hauptergebnisse dieser Arbeit wurden in der Natuurwetenschappelyk Tydschrift (Flämisch) No. 2–5, 1934, mitgeteilt.  相似文献   
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The inbred rat strains Lewis (LEW) and Spontaneously Hypertensive Rats (SHR) differ with respect to several emotionality- and ethanol intake-related behaviors, one of which (inner locomotion in the open field; OF) is strongly influenced by a locus (Anxrr16) on chromosome (Chr) 4. We aimed to further investigate the influence of Chr 4 on these behaviors and to evaluate the role of the estrous cycle in QTL expression. LEW females and SHR males were intercrossed to produce F1 and F2 rats (96?C97/sex), which were then tested in the OF, light?Cdark box (LDB), forced swimming test (FST), and an ethanol consumption procedure (ECP). In addition, another group of 96 F2 females were tested in the OF and LDB according to their estrous cycle phase. All animals were genotyped for microsatellite markers located on Chr 4 and two QTL analyses were performed. A factor analysis of the F2 population produced five factors reflecting different behavioral dimensions. QTL analysis revealed five significant loci in males, some of which with pleiotropic effects on behaviors measured in the OF, LDB, and ECP. The second QTL analysis revealed two significant loci in females in diestrous?Cproestrous and one in females in estrous?Cmetestrous that influence behaviors in the OF and LDB. Results revealed that Anxrr16 and four other new QTL influence emotionality- and ethanol-related behaviors in male rats, whereas Anxrr16 attained suggestive levels only in females in diestrous?Cproestrous, which raises the need for taking into account factors related to the sex and estrous cycle in behavioral QTL analysis.  相似文献   
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