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121.
Christine A. Howell Julian K. Wood Mark D. Dettling Kenneth Griggs Codie C. Otte Linette Lina Thomas Gardali 《西北部美国博物学家》2011,70(1)
The Least Bell’s Vireo ( Vireo bellii pusillus ) was listed as state endangered in 1980 and federally endangered in 1986 in response to a sharp population decline and range reduction. This vireo commonly bred in riparian forests throughout the Central Valley of California, but prior to 2005, no nesting pairs had been confirmed in the region in over 50 years. On 29 June 2005, a Least Bell’s Vireo nest was located in a 3-year-old riparian restoration site at the San Joaquin River National Wildlife Refuge in Stanislaus County, California. In 2006, a Least Bell’s Vireo pair returned to the refuge to successfully breed, followed by an unsuccessful attempt in 2007 by an unpaired female. These records are approximately 350 km from the nearest known breeding population and appear to be part of a growing number of sightings outside of the species’ current southern California breeding range. These nesting attempts lend credence to the idea that extirpated species can recolonize restored habitat by long-distance dispersal. 相似文献
122.
The hydrological simulation program FORTRAN (HSPF) is a comprehensive watershed model designed to simulate water quantity and quality processes.It is used widely throughout the world.Calculating discharge from a stream reach by HSPF is based mainly on function tables (FTABLEs),which describe the relationship between surface area,stream stage,volume,and discharge.The traditional method of FTABLE generation (using general stream cross-sections and the Manning equation or other discharge relationships) can be time-consuming and inaccurate when there are limited calibration stations and survey data.Recent insights into generalized coupled stage/storage and stage/discharge relationships,however,offer the potential to improve both the speed and accuracy of compiling FTABLEs and thus HSPF models.This study tested the application of these insights in generating FTABLEs.The study domain included 18 gauging stations in a coastal plain environment on the Peace River watershed in West-Central Florida.In the calibration of this model,wetlands were treated as reaches in HSPF with storage-attenuation characteristics.Over the simulation period,the modeled daily flow and stage correlated well with observed data at all ganging stations along the Peace River.The Nash-Sutcliffe efficiency and correlation coefficient computed using observed and simulated daily flows were 0.90 and 0.91,respectively,at the Peace River outlet.Rigorous testing found that the new system for calibrating the FTABLEs improved the model predictive ability and efficiency.Uncertainty in un-calibrated station performance was also reduced.The model parameters obtained in this study could potentially serve as reference values for model application in similar climatic regions.They may also have particular relevance in disaster management,as the simulation period extended over the hurricane season of 2004,and the model domain was within a high hurricane impact zone.The possible effects of hurricanes on discharge are also briefly discussed. 相似文献
123.
We describe the synthesis of some new derivatives of benzo(4, 5)cyclohepta(1, 2-b)thiophene which inhibit ovulation and the secretion of luteinizing hormone (LH) in the rat. We also describe the relationship between the structure and activity of these compounds. 相似文献
124.
H Lesot K von der Mark J V Ruch 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(10):765-768
The different types of collagen synthesized by embryonic Mouse tooth germs were analysed using an immunohistiological method. The tooth germs were shown to synthesize at least three genetically distinct collagen types: I, III and IV. 相似文献
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Summary The effects of the novel and selective dopamine D-1 agonist CY 208-243 on the rat hypothalamo-hypophyseal-gonadal (HHG) axis were studied. CY 208-243 did not modify the concentration of luteinizing hormone (LH) in serum from female or male rats, and had no effect upon opiate antagonist-induced stimulation of LH secretion in male rats. CY 208-243 did not inhibit ovulation in cycling female rats. Thus, D-1 receptor activation by systemic drug administration does not alter HHG function in rats. 相似文献
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Monsuur AJ de Bakker PI Alizadeh BZ Zhernakova A Bevova MR Strengman E Franke L van't Slot R van Belzen MJ Lavrijsen IC Diosdado B Daly MJ Mulder CJ Mearin ML Meijer JW Meijer GA van Oort E Wapenaar MC Koeleman BP Wijmenga C 《Nature genetics》2005,37(12):1341-1344
Celiac disease is probably the best-understood immune-related disorder. The disease presents in the small intestine and results from the interplay between multiple genes and gluten, the triggering environmental factor. Although HLA class II genes explain 40% of the heritable risk, non-HLA genes accounting for most of the familial clustering have not yet been identified. Here we report significant and replicable association (P = 2.1 x 10(-6)) to a common variant located in intron 28 of the gene myosin IXB (MYO9B), which encodes an unconventional myosin molecule that has a role in actin remodeling of epithelial enterocytes. Individuals homozygous with respect to the at-risk allele have a 2.3-times higher risk of celiac disease (P = 1.55 x 10(-5)). This result is suggestive of a primary impairment of the intestinal barrier in the etiology of celiac disease, which may explain why immunogenic gluten peptides are able to pass through the epithelial barrier. 相似文献
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