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401.
Background
The urokinase plasminogen activator receptor associated protein (uPARAP)/Endo180 is a novel endocytic receptor that mediates collagen uptake and is implicated to play a role in physiological and pathological tissue-remodelling processes by mediating intracellular collagen degradation. 相似文献402.
403.
Abstract 1 Based on climate data from a network of agrometeorological stations in Norway, the effects of current and future climate regimes on the spatial and temporal distribution of the Codling moth (Cydia pomonella) and the establishment potential of the Colorado potato beetle (Leptinotarsa decemlineata) were investigated. 2 The study was accomplished using climex , a dynamic climate matching‐ and climate response estimation model, which predicts potential distribution of an organism based on its known geographical distribution. 3 Validation of the climex model predictions for C. pomonella against field data on spatial distribution of the species in Norway resulted in a refined set of climate response parameters for C. pomonella. Temporal occurrence of C. pomonella seems to be affected by climate (temperature) and insecticide treatment against the Apple fruit moth (Argyresthia conjugella) in the previous season. 4 Climate change scenarios (0.1 °C increase per degree in latitude in daily maximum and minimum temperatures) indicated an extension of the potential geographical range for C. pomonella, and 23 new locations were found favourable for its long‐term survival. The abundance and pest status of C. pomonella could increase dramatically in those locations where the species is already established. 5 Leptinotarsa decemlineata would only temporarily find suitable climate conditions in Norway and hence only be able to establish interim populations in a few regions under current climate conditions. Climate change scenarios for L. decemlineata indicated that the species would be able to establish as far north as 64°N, mainly in the inland of eastern Norway. 6 In general, the methods applied support the process of decreasing the uncertainty both in our knowledge about the pests themselves and about the environment, which are crucial elements in predicting whether a species is able to establish in a new area. 相似文献
404.
51 species of agaricoid, clavarioid, and heterobasidiomycetous fungi are recorded from Thailand. 40 species are new to the area. Hohenbuehelia panelloides Hoiland sp. nov. is described and Leccinum intusrubens (Corner) Hoiland comb. nov. is proposed. Comments are given on vernacular names. 相似文献
405.
Food limitation in asynchronous bluethroat broods: effects on food distribution, nestling begging, and parental provisioning rules 总被引:2,自引:0,他引:2
Scramble competition models of begging predict that junior nestlingswill be more affected by food limitation than seniors. Thesemodels assume that food allocation is under offspring controland, hence, predict that this change in food distribution iscaused by a differential behavioral response by seniors andjuniors. By using the bluethroat (Luscinia svecica svecica)as our model species, we induced food limitation by removingthe male parent temporarily. We found that, as predicted, fooddistribution became more biased in disfavor of juniors whenfood was limited. However, there was no significant differencein the behavioral responses of seniors and juniors (i.e., positioningin the nest or begging postures) to food limitation that couldexplain the change in food distribution. Hence, there was noevidence that seniors controlled food distribution. As predictedif parents preferentially fed seniors, nestling rank affectedfood distribution when controlling for variation in nestlingbehaviors. Furthermore, as expected if the increased skew infood distribution under food limitation was caused by activefood allocation by parents, nestling rank had a greater effecton food distribution under food limitation than under normalconditions. The present study suggests that food distributionin passerine birds is determined not only by nestling behaviors(begging posture and positioning) alone but also by parentalpreferences for seniors based on nonsignaling cues, such asbody size. 相似文献
406.
407.
Helge Tolleshaug Trond Berg Kari Holte 《Biochimica et Biophysica Acta (BBA)/General Subjects》1982,714(1):114-121
The effects of local anesthetics, including procaine and dibucaine, and some related amine compounds, such as dansyl-cadaverine, were studied with respect to their effects on the uptake and degradation of asialo-glycoproteins in isolated hepatocytes 0.5 mM of either dibucaine or dansyl-cadaverine reduced the rates of uptake to 18–19% of control values; other amines were less effective. Dibucaine and dansyl-cadaverine both acted by reducing the surface binding capacity of the cells as well as by reducing the rate of internalization of surface-bound asialo-glycoprotein. All of the compounds that affected the uptake, including dansyl-cadaverine, also reduced the rate of degradation. This effect could be studied separately from their effect on uptake. The concentrations that were required in order to reduce degradation were, in general, 0.5-0.25 of those which caused a reduction in the uptake. Even though dibucaine, lidocaine and dansyl-cadaverine were found to accumulate in the lysosomes, it was concluded from studies with isopycnic centrifugation in sucrose gradients that all three compounds inhibited the rate of transfer of endocytosed protein from endocytic vesicles to lysosomes. This effect could be due to a reduced rate of fusion between endocytic vesicles and lysosomes. 相似文献
408.
Parakiefferiella lagorum spec. nov. from central Chile is described and figured as male, female and pupa; P. hernandezi spec. nov. from south Chile and P. strixinorum spec. nov. from southeast Brazil as males and pupae; and P. wardorum spec. nov. from south Chile, as male only. In addition, an unassociated pupa from south Chile is described and figured. Keys to the Parakiefferiella males and pupae from South America are provided. 相似文献
409.
Reference gene selection for quantitative real-time PCR normalization in tomato subjected to nitrogen, cold, and light stress 总被引:3,自引:0,他引:3
We examined eight putative consistently expressed genes—actin (ACT), β-tubulin, elongation factor 1α (EF1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), phosphoglycerate kinase (PGK), ribosomal protein L2 (RPL2), ubiquitin (UBI), and a catalytic subunit of protein phosphatase 2A (PP2Acs)—for their potential as references for the normalization of gene expression in tomato leaves. Expression stability of candidate reference genes was tested during growth conditions of nitrogen (N) starvation, low temperature, and suboptimal light. The geNorm algorithm, using reciprocal cross-validation among a larger group of candidate references, was applied for this purpose. The widely used reference genes GAPDH and PGK were top ranked during light stress but poorly ranked during N and cold stress. In contrast, EF1 was top ranked during N and cold stress but poorly ranked during light stress. The novel references RPL2 and PP2Acs, as well as the traditional references ACT and UBI, appeared to be stably expressed when looking at the data set as a whole. No gene was identified that exhibited such a constant level of expression as to outperform the other candidates under all experimental conditions. Thus, the results highlight the need for normalizing gene expression in tomato using the geometric average of multiple carefully selected reference genes. 相似文献
410.