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51.

Background

The genus Micronycteris is a diverse group of phyllostomid bats currently comprising 11 species, with diploid number (2n) ranging from 26 to 40 chromosomes. The karyotypic relationships within Micronycteris and between Micronycteris and other phyllostomids remain poorly understood. The karyotype of Micronycteris hirsuta is of particular interest: three different diploid numbers were reported for this species in South and Central Americas with 2n?=?26, 28 and 30 chromosomes. Although current evidence suggests some geographic differentiation among populations of M. hirsuta based on chromosomal, morphological, and nuclear and mitochondrial DNA markers, the recognition of new species or subspecies has been avoided due to the need for additional data, mainly chromosomal data.

Results

We describe two new cytotypes for Micronycteris hirsuta (MHI) (2n?=?26 and 25, NF?=?32), whose differences in diploid number are interpreted as the products of Robertsonian rearrangements. C-banding revealed a small amount of constitutive heterochromatin at the centromere and the NOR was located in the interstitial portion of the short arm of a second pair, confirmed by FISH. Telomeric probes hybridized to the centromeric regions and weakly to telomeric regions of most chromosomes. The G-banding analysis and chromosome painting with whole chromosome probes from Carollia brevicauda (CBR) and Phyllostomus hastatus (PHA) enabled the establishment of genome-wide homologies between MHI, CBR and PHA.

Conclusions

The karyotypes of Brazilian specimens of Micronycteris hirsuta described here are new to Micronycteris and reinforce that M. hirsuta does not represent a monotypic taxon. Our results corroborate the hypothesis of karyotypic megaevolution within Micronycteris, and strong evidence for this is that the entire chromosome complement of M. hirsuta was shown to be derivative with respect to species compared in this study.
  相似文献   
52.
Sulphate uptake and its distribution within plants depend on the activity of different sulphate transporters (SULTR). In long‐living deciduous plants such as trees, seasonal changes of spatial patterns add another layer of complexity to the question of how the interplay of different transporters adjusts S distribution within the plant to environmental changes. Poplar is an excellent model to address this question because its S metabolism is already well characterized. In the present study, the importance of SULTRs for seasonal sulphate storage and mobilization was examined in the wood of poplar (Populus tremula × P. alba) by analysing their gene expression in relation to sulphate contents in wood and xylem sap. According to these results, possible functions of the respective SULTRs for seasonal sulphate storage and mobilization in the wood are suggested. Together, the present results complement the previously published model for seasonal sulphate circulation between leaves and bark and provide information for future mechanistic modelling of whole tree sulphate fluxes.  相似文献   
53.
The effect of price information on hedonic and use intention responses to a chocolate bar was investigated in the absence and presence of a health claim related to energy, satiety value and cholesterol content. First, Finnish students (n = 79) tasted and rated blind three chocolate bars (one regular, two containing functional ingredients). Second, one group (“Informed,” n = 40) evaluated the samples with the health claim and price information, the other group (“Control,” n = 39) as a regular bar with price information only. A separate focus group (n = 6) interview was conducted to obtain further views of the claim and samples. Neither the health claim nor the price affected pleasantness ratings, while the increasing price significantly reduced the likelihood of buying and preferred frequency of eating the chocolate bar in both groups. Price affected the likelihood of buying more strongly among females than among males, and involvement with chocolate bars affected the likelihood of buying in the control, but not in the informed group. The focus group interview indicated that healthfulness might be irrelevant for chocolate products. Overall, price heavily affected the likelihood of buying the target product, but price and the health claim were incapable of altering hedonic responses to it.  相似文献   
54.
Ion channel mapping techniques are described and the results for two fungal organisms, Saprolegnia ferax and Neurospora crassa, are presented. In these species, two channel types have been characterized, stretch-activated channels exhibiting significant calcium permeability and spontaneous channels having significant potassium permeability. Two distinct analyses of patch clamp data, analysis of channel self-clustering and association between different channel types, and localization along the hyphae, reveal significant differences between the two organisms. S. ferax maintains a tip-high gradient of both channel types which is lost after disruption of the actin cytoskeleton. There is significant self-clustering of the channels, as well as interactions between channel types. N. crassa on the other hand does not maintain tip-high gradients, and clustered distributions are observed only for the stretch-activated channels. In terms of physiological roles, evidence is quite strong that the stretch-activated channels function as a growth sensor in S. ferax, but have an unknown function in N. crassa. In both organisms, the potassium permeable channels presumably function in potassium uptake. The differences between these two organisms may be due, in part, to differences in their normal environment: aquatic versus terrestrial. Copyright 1998 Academic Press.  相似文献   
55.
To establish the likelihood of purchase and acceptability level of new fresh-cut apples, the responses of two categories of consumers, children and adults, were evaluated. The effect of storage time on acceptability was investigated and the shelf life of fresh-cut apples was determined by using a Weibull hazard model.
The samples were distributed at different storage time (from second to fifth day) at the Science Museum of Naples as part of an educational program for children to evaluate the likelihood of buying and the acceptability level of the product. The data were collected over 5 weeks, and the test was performed in 2,421 children and 224 adults. The product was distributed at the University of Naples at different storage time (time 0 to 10 days) to perform the Weibull test using 63 consumers.
The adults and children appreciated the product, and the adults were generally willing to buy it. The Weibull analysis proved an appropriate method to evaluate product shelf life, which was estimated at 7.5 days at 4C.

PRACTICAL APPLICATIONS


This study contributes to enhance the competitiveness of a traditional food as Protected Geographical Indication Annurca apples. In fact, an attractive way to improve the consumption of this variety of apple is to market it as a ready-to-eat product. Also, the research allows for a better understanding of the children's acceptability level of new fresh-cut apples in order to improve the intake of apples among primary schoolchildren. In fact, an interesting way to increase the children's consumption of fruit is to distribute it at school level and also to increase the convenience for children. Finally, the fact that the product was distributed to the Science Museum of Naples can be considered as a premarket test for a new product launch.  相似文献   
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