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51.
A. Gaylon Cook 《西北部美国博物学家》2011,44(4)
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} The Common Loon, White Pelican, Double-crested Cormorant, recurvirostrids, and most grebes, waterfowl, gulls, and terns have become more abundant in Uintah County, Utah, since 1937 (Twomey 1942) due to the establishment of Pelican Lake and adjacent water bodies and the ponds and marshes at Ouray National Wildlife Refuge and Pariette Wetlands Wildlife Management Area. The incidence of herons, egrets, thrushes, nuthatches, and icterids has generally remained about the same since 1937. Diurnal raptors have largely declined in abundance in the desert region of Uintah County since Twomey’s (1942) study. Plovers, sandpipers, phalaropes, and the White-faced Ibis were generally less common in 1977–1982 than in 1937, perhaps chiefly due to their displacement from wintering grounds by human population expansion and agricultural and industrial development. The incidence of owl species remains constant. Most flycatchers, swallows, warblers, vireos, orioles, and emberizids have diminished in number since 1937, probably because of the shrinkage of their winter habitats in Latin America and the southwestern U.S. The Blue Grosbeak and Black-throated Sparrow were not recorded in Uintah County in 1937 but were found there during this study and may represent a range extension northward since 1937. The Blue-gray Gnatcatcher is more common now than in 1937 due to the northward extension of its range. The Starling and Rock Dove and, more recently, the Common Grackle, Great-tailed Grackle, and Cattle Egret have invaded Uintah County due to the expansion of their ranges. It is not clear why the Pine Siskin, House Finch, and most corvids are presently less common than in 1937. 相似文献
52.
D E Cook 《Experientia》1978,34(3):315-316
2 months after bilateral vasectomy the metabolism of aniline but not aminopyrine was increased in rat liver homogenates, whereas vasectomy did not affect the metabolism of either compound in guinea-pig liver homogenates. 相似文献
53.
Quantitative structure activity relationships suggest that the binding of quinoline and phenanthroline analogs to D-lactate dehydrogenase from the barnacle, Balanus nubilus Darwin, does not involve primarily hydrophobic effects. This phenomenon appears to exist also for other lactate dehydrogenases. 相似文献
54.
R.库克 《国外科技新书评介》2006,(12):24-25
2002年6月在西班牙的特内里费岛(Tenerife)举行了规模最大的“第四届国际线虫学大会”,有500多位代表参加。此次会议分为23个分会场,与会特邀代表交流了近年在线虫学研究的进展,特别是在植物线虫致病性基因、线虫寄主信号识别的分子机制、巴氏杆菌的人工培养、线虫的分子诊断等方面取得突出进展,本书是这次会议的论文集。内容涵盖线虫流行和检疫、利用线虫多样性作为指示生物、利用抗性和育种防治植物线虫病害、集约化和精准农业中的线虫治理方法、有机改良剂和线虫生防因子的市场开发等所有线虫学方面的研究进展,具有很高的科学价值和参考价值。 相似文献
55.
Locke DP Hillier LW Warren WC Worley KC Nazareth LV Muzny DM Yang SP Wang Z Chinwalla AT Minx P Mitreva M Cook L Delehaunty KD Fronick C Schmidt H Fulton LA Fulton RS Nelson JO Magrini V Pohl C Graves TA Markovic C Cree A Dinh HH Hume J Kovar CL Fowler GR Lunter G Meader S Heger A Ponting CP Marques-Bonet T Alkan C Chen L Cheng Z Kidd JM Eichler EE White S Searle S Vilella AJ Chen Y Flicek P Ma J Raney B Suh B Burhans R Herrero J Haussler D Faria R Fernando O Darré F Farré D Gazave E Oliva M 《Nature》2011,469(7331):529-533
'Orang-utan' is derived from a Malay term meaning 'man of the forest' and aptly describes the southeast Asian great apes native to Sumatra and Borneo. The orang-utan species, Pongo abelii (Sumatran) and Pongo pygmaeus (Bornean), are the most phylogenetically distant great apes from humans, thereby providing an informative perspective on hominid evolution. Here we present a Sumatran orang-utan draft genome assembly and short read sequence data from five Sumatran and five Bornean orang-utan genomes. Our analyses reveal that, compared to other primates, the orang-utan genome has many unique features. Structural evolution of the orang-utan genome has proceeded much more slowly than other great apes, evidenced by fewer rearrangements, less segmental duplication, a lower rate of gene family turnover and surprisingly quiescent Alu repeats, which have played a major role in restructuring other primate genomes. We also describe a primate polymorphic neocentromere, found in both Pongo species, emphasizing the gradual evolution of orang-utan genome structure. Orang-utans have extremely low energy usage for a eutherian mammal, far lower than their hominid relatives. Adding their genome to the repertoire of sequenced primates illuminates new signals of positive selection in several pathways including glycolipid metabolism. From the population perspective, both Pongo species are deeply diverse; however, Sumatran individuals possess greater diversity than their Bornean counterparts, and more species-specific variation. Our estimate of Bornean/Sumatran speciation time, 400,000?years ago, is more recent than most previous studies and underscores the complexity of the orang-utan speciation process. Despite a smaller modern census population size, the Sumatran effective population size (N(e)) expanded exponentially relative to the ancestral N(e) after the split, while Bornean N(e) declined over the same period. Overall, the resources and analyses presented here offer new opportunities in evolutionary genomics, insights into hominid biology, and an extensive database of variation for conservation efforts. 相似文献
56.
McDermott-Roe C Ye J Ahmed R Sun XM Serafín A Ware J Bottolo L Muckett P Cañas X Zhang J Rowe GC Buchan R Lu H Braithwaite A Mancini M Hauton D Martí R García-Arumí E Hubner N Jacob H Serikawa T Zidek V Papousek F Kolar F Cardona M Ruiz-Meana M García-Dorado D Comella JX Felkin LE Barton PJ Arany Z Pravenec M Petretto E Sanchis D Cook SA 《Nature》2011,478(7367):114-118
Left ventricular mass (LVM) is a highly heritable trait and an independent risk factor for all-cause mortality. So far, genome-wide association studies have not identified the genetic factors that underlie LVM variation, and the regulatory mechanisms for blood-pressure-independent cardiac hypertrophy remain poorly understood. Unbiased systems genetics approaches in the rat now provide a powerful complementary tool to genome-wide association studies, and we applied integrative genomics to dissect a highly replicated, blood-pressure-independent LVM locus on rat chromosome 3p. Here we identified endonuclease G (Endog), which previously was implicated in apoptosis but not hypertrophy, as the gene at the locus, and we found a loss-of-function mutation in Endog that is associated with increased LVM and impaired cardiac function. Inhibition of Endog in cultured cardiomyocytes resulted in an increase in cell size and hypertrophic biomarkers in the absence of pro-hypertrophic stimulation. Genome-wide network analysis unexpectedly implicated ENDOG in fundamental mitochondrial processes that are unrelated to apoptosis. We showed direct regulation of ENDOG by ERR-α and PGC1α (which are master regulators of mitochondrial and cardiac function), interaction of ENDOG with the mitochondrial genome and ENDOG-mediated regulation of mitochondrial mass. At baseline, the Endog-deleted mouse heart had depleted mitochondria, mitochondrial dysfunction and elevated levels of reactive oxygen species, which were associated with enlarged and steatotic cardiomyocytes. Our study has further established the link between mitochondrial dysfunction, reactive oxygen species and heart disease and has uncovered a role for Endog in maladaptive cardiac hypertrophy. 相似文献
57.
A distinct Hox code for the branchial region of the vertebrate head. 总被引:20,自引:0,他引:20
P Hunt M Gulisano M Cook M H Sham A Faiella D Wilkinson E Boncinelli R Krumlauf 《Nature》1991,353(6347):861-864
The branchial region of the vertebrate head forms through complex interactions involving rhombomeric segments, neural crest and branchial arches. It is though that aspects of their patterning mechanisms are linked and involve Hox-2 genes, whose overlapping and spatially restricted expression domains represent a combinatorial code for generating regional diversity. Vertebrates possess four Hox clusters of Antennapedia class homeobox genes, related to each other by duplication and divergence from a common ancestral complex. In consequence, at equivalent positions in different clusters there are highly related genes known as subfamilies or paralogous groups. As Hox-2 genes cannot fully account for patterning individual rhombomeres, we investigated whether offsets in expression limits of paralogous genes could account for the generation of regional diversity. We report here that, with the exception of the labial subfamily, paralogues show identical expression limits in rhombomeres, cranial ganglia and branchial arches, providing a combinatorial Hox code for the branchial region that seems to be different in organization to that of the trunk. 相似文献
58.
59.
N. D. Cook 《Cellular and molecular life sciences : CMLS》1978,34(4):419-421
Summary By stipulating that like-fermions adjacent in space must be singlet paired, geometric considerations alone produce closed electron shells at the 6 noble gases and, similarly, closed nucleon shells and subshells isomorphic with those of the harmonic oscillator used in nuclear theory. 相似文献
60.
John S. Cook 《Cellular and molecular life sciences : CMLS》1956,12(9):349-350
Zusammenfassung Die marklosen Nerven-Einzelfasern vonCarcinus maenas wurden mit monochromatischem Ultraviolett bestrahlt. Zuerst tritt bei Bestrahlung ein langsamer Abfall der Reizschwelle, dann ein rascher Abfall, gefolgt von einem steilen Anstieg auf. Der Abfall rührt von einer Depolarisation her, deren Zunahme dann zu Unerregbarkeit führt. Durch Verbesserung der Ableitungstechnik konnten die elektrischen Veränderungen lokalisiert an der bestrahlten Stelle gemessen werden. Anstieg der Reizschwelle, Abfall der Steilheit und Abfall der Höhe des Spitzenpotentials wurden auch bei diesen marklosen Fasern beobachtet, aber nicht so ausgeprägt wie bei der Bestrahlung markhaltiger Fasern.
This work was carried out during the tenure of a Postdoctoral fellowship from the United States Public Health Service. 相似文献
This work was carried out during the tenure of a Postdoctoral fellowship from the United States Public Health Service. 相似文献