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991.
Graphs allowing interconversion between various physical chemical parameters are presented for five Artemia habitats in the western USA. Both the mean osmosity and its typical yearly range differ greatly among habitats. Consequently, Artemia populations provide an interesting opportunity to study physiological and life history adaptations to differing degrees of habitat stability. 相似文献
992.
Loran C. Anderson 《西北部美国博物学家》2011,40(4)
The new, presumably extinct species, Chrysothamnus pulchelloides, is formally described and illustrated. The plant materials came from Holocene packrat middens. Anatomical and phyletic relationships of the fossil species to extant taxa are discussed. 相似文献
993.
C. Rose Broome 《西北部美国博物学家》2011,41(2)
An expression of Centaurium namophilum (Gentianaceae), long confused with C. exaltatum in the Great Basin of the western United States, is described and designated as var. nevadense. It may be separated from the Death Valley region endemic, var. namophilum, by its broader leaves, its diffuse corymbose cyme, the ultimate peduncles that are longer than the flowers, its medium to deep rose pink corolla, and its stamens that equal or exceed the style and are only slightly exserted from the corolla-tube. The var. nevadense occurs from eastern California to western Utah, and from southeastern Oregon and adjacent Idaho south to the northern Mojave Desert of southeastern California. Centaurium exaltatum may be distinguished from the new variety by its broader, more elliptical leaves, dichotomous peduncles, paler pink or bluish and generally four-merous flowers, shorter and more blunt corolla lobes, and a thicker, more included style and stigma. 相似文献
994.
Reproduction in L. pyromelana infralabialis Tanner is reported. Eggs were measured and weighed and incubation time and hatching reported. Hatchlings were measured and weighed, and feeding was observed. 相似文献
995.
996.
Sceloporus megalepidurus halli, subsp. nov., is described from San José Lachiguiri, Oaxaca, Mexico, from one adult male. 相似文献
997.
Three condition models for wintering Northern Pintails ( Anas acuta ) were tested for their ability to predict fat mass, logarithm of fat mass, or a condition index (CI) incorporating fat mass. Equations generated to predict fat mass and the logarithm of fat mass accounted for more than 69% of the variation in these dependent variables. Log transformations of body mass, wing length, and total length explained at least 60% of the variation in CI. All models performed better on an independent data set. Mean prediction error was minimal (≤8% of measured variables) and negative for all models. Regression models apply to live and dead pintails and thus represent tools that have utility in a wide variety of studies on pintail condition. 相似文献
998.
Stems bearing egg masses of the western tent caterpillar ( Malacosoma californicum ), collected in Arizona and northern New Mexico during 1977–1980, had mean diameters between 2.9 and 4 mm. Mean lengths of the egg masses were consistently between 11 and 14 mm. 相似文献
999.
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* 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;} Past observations and ongoing population surveys indicate daily and yearly vertical movement of the Devil’s Hole pupfish, Cyprinodon diabolis Wales, within the upper 27 m of the water column in Devil’s Hole, Nevada. This movement involves occupying and leaving a 5 by 3.5 m rock shelf during daily and yearly periods of maximum light intensity. 相似文献
1000.
van de Laar IM Oldenburg RA Pals G Roos-Hesselink JW de Graaf BM Verhagen JM Hoedemaekers YM Willemsen R Severijnen LA Venselaar H Vriend G Pattynama PM Collée M Majoor-Krakauer D Poldermans D Frohn-Mulder IM Micha D Timmermans J Hilhorst-Hofstee Y Bierma-Zeinstra SM Willems PJ Kros JM Oei EH Oostra BA Wessels MW Bertoli-Avella AM 《Nature genetics》2011,43(2):121-126
Thoracic aortic aneurysms and dissections are a main feature of connective tissue disorders, such as Marfan syndrome and Loeys-Dietz syndrome. We delineated a new syndrome presenting with aneurysms, dissections and tortuosity throughout the arterial tree in association with mild craniofacial features and skeletal and cutaneous anomalies. In contrast with other aneurysm syndromes, most of these affected individuals presented with early-onset osteoarthritis. We mapped the genetic locus to chromosome 15q22.2-24.2 and show that the disease is caused by mutations in SMAD3. This gene encodes a member of the TGF-β pathway that is essential for TGF-β signal transmission. SMAD3 mutations lead to increased aortic expression of several key players in the TGF-β pathway, including SMAD3. Molecular diagnosis will allow early and reliable identification of cases and relatives at risk for major cardiovascular complications. Our findings endorse the TGF-β pathway as the primary pharmacological target for the development of new treatments for aortic aneurysms and osteoarthritis. 相似文献