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321.
322.
Pharmacogenetics and disease genetics of complex diseases   总被引:4,自引:0,他引:4  
Advances in technologies and the availability of a single nucleotide polymorphism (SNP) map are beginning to show the true potential for the human genome project to affect patient healthcare. A whole genome scan, the use of 100,000–300,000 SNPs across the genome, is now possible. Use of traditional approaches and the whole genome scan will result in identification of disease susceptibility genes and development of many new treatments in the longer term. In the shorter term, the goal will be to predict those patients at risk to experience an adverse reaction or those with a high probability for improved efficacy (i.e. pharmacogenetics). As progress is made in the area of disease genetics and pharmacogenetics, our understanding of disease susceptibility and its interrelationship with drug response will improve, making targeted therapy (i.e. the right drug to the right patient) a reality.Received 19 December 2002; received after revision 14 February 2003; accepted 20 February 2003  相似文献   
323.
The torsion balance, an instrument that was first developed to demonstrate the high precision of physical science in the laboratory became a different sort of demonstration instrument in its brief vogue in the 1920s. This article considers intersecting stories of acquiring and testing the torsion balance as a field instrument in Canada, Britain and Australia. It examines the purchasing trip and fieldwork of A. H. Miller of the Dominion Observatory in 1928–1931, testing conducted by the British Geological Survey in 1926–1930, and finally the Imperial Geophysical Experimental Survey of 1928–1930 in Australia. These different stories produce a kind of collective biography, illustrating well the variety of material and textual records that accrete around instruments, especially expensive ones. But the trials and travels of the torsion balance also point to large themes. By comparing the different ways an instrument becomes valuable, and to whom, these micro-histories reveal significant features of the developing identity of geophysics. They also show the interaction of different forms of scientific internationalism in the inter-war period.  相似文献   
324.
Atmospheric carbon dioxide concentrations and climate are regulated on geological timescales by the balance between carbon input from volcanic and metamorphic outgassing and its removal by weathering feedbacks; these feedbacks involve the erosion of silicate rocks and organic-carbon-bearing rocks. The integrated effect of these processes is reflected in the calcium carbonate compensation depth, which is the oceanic depth at which calcium carbonate is dissolved. Here we present a carbonate accumulation record that covers the past 53 million years from a depth transect in the equatorial Pacific Ocean. The carbonate compensation depth tracks long-term ocean cooling, deepening from 3.0-3.5?kilometres during the early Cenozoic (approximately 55?million years ago) to 4.6 kilometres at present, consistent with an overall Cenozoic increase in weathering. We find large superimposed fluctuations in carbonate compensation depth during the middle and late Eocene. Using Earth system models, we identify changes in weathering and the mode of organic-carbon delivery as two key processes to explain these large-scale Eocene fluctuations of the carbonate compensation depth.  相似文献   
325.
326.
We described 15 Ruffed Grouse ( Bonasa umbellus ) drumming logs and adjacent habitat within Grand Teton National Park, Wyoming. Drumming logs and adjacent habitat differed from 30 random non-drumming sites. Drumming logs had fewer limbs (8; P = 0.003) and a smaller percentage of bark remaining (12%; P = 0.0001). These logs were in advanced stages of decay but were still firm to the touch. Additionally, drumming logs were found close to clearings but in areas with increased amounts of undergrowth and mature trees. Adjacent habitat analysis (0.04-ha circular plot centered on logs) indicated drumming locations had significantly greater average canopy height, more vegetative cover consisting of conifer and total canopy cover, and more vertical foliage between 0.3 m and 3.0 m in height. Adjacent habitat was in advanced stages of maturity as indicated by significant numbers of both large-diameter logs and largediameter lodgepole pine ( Pinus contorta ) and quaking aspen ( Populus tremuloides ) snags. Tree species dominating the canopy and subcanopy were large-diameter Engelmann spruce ( Picea engelmannii ), lodgepole pine, and quaking aspen. Subalpine fir ( Abies lasiocarpa ) and quaking aspen saplings were more numerous at used sites. Ruffed Grouse drummed in coniferous areas within close proximity of quaking aspen.  相似文献   
327.
Two groups of glabrous, narrow-leaved Chrysothamnus viscidiflorus (Asteraceae) are perceived, and appropriate taxonomic combinations are made, i.e., C. v. ssp. viscidiflorus var. stenophyllus and C. v. ssp. axillaris. The two are fairly distinct geographically, and they can be separated by floral morphology. A key to all species of section Chrysothamnus (to which C. viscidiflorus belongs) is given.  相似文献   
328.
Natural gas extraction and field development are pervasive throughout the sagebrush steppe of Wyoming. We conducted this study to determine how roads associated with natural gas extraction affect the distribution of breeding songbirds in sagebrush steppe habitat. The study encompassed dirt and paved roads in the Jonah Field II and Pinedale Anticline Project Area in Sublette County, Wyoming. Sites are dominated by Wyoming big sagebrush ( Artemisia tridentata ), and common passerines include sagebrush obligates: Brewer's Sparrows ( Spizella breweri ), Sage Sparrows ( Amphispiza belli ), and Sage Thrashers ( Oreoscoptes montanus ); and non-obligates: Horned Larks ( Eremophila alpestris ) and Vesper Sparrows ( Pooecetes gramineus ). Species relative density was measured using 50-m-radius point counts during spring 1999 and 2000. Four roads with low traffic volumes (700-10 vehicles per day) were surveyed and point counts were centered at variable distances from the road surface such that relative densities were measured 0-600 m from the road's edge. Density of sagebrush obligates, particularly Brewer's and Sage Sparrow, was reduced by 39%-60% within a 100-m buffer around dirt roads with low traffic volumes (700-10 vehicles per day). While a 39%-60% reduction in sagebrush obligates within 100 m of a single road may not be biologically significant, the density of roads created during natural gas development and extraction compounds the effect, and the area of impact can be substantial. Traffic volume alone may not sufficiently explain observed declines adjacent to roads, and sagebrush obligates may also be responding to edge effects, habitat fragmentation, and increases in other passerine species along road corridors. Therefore, declines may persist after traffic associated with extraction subsides and perhaps until roads are fully reclaimed.  相似文献   
329.
From 1984 through 1985 a study was made of the influence of a retained mine highwall on a wildlife community in south central Wyoming. Vegetation species richness and diversity were greater near the highwall compared with two adjacent sites 150 m in front of and behind the highwall. However, vegetation abundance (cover) was greater on the two adjacent sites. Small mammal abundance, richness, and diversity were greater on the highwall than on the two adjacent sites. Male bird abundance, richness, and diversity were greatest in front of the highwall (+ 50 m to + 350 m) compared with the highwall and the area behind the highwall.  相似文献   
330.
Long-billed curlew populations were studied in the upper Green River Basin of Wyoming. Sites were selected where curlew populations appear constant in numbers and declining in numbers. Results show that while few habitat differences were found between the two areas, disturbances such as grazing and dragging during nesting reduced productivity. Nest failures were also correlated with field fertilization and early season grazing. Within each area curlews nested successfully on field sites that were elevated and had adequate grass cover but not tall grass.  相似文献   
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