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51.
52.
Craig Guyer Christopher Murray Henry L. Bart Brian I. Crother Ryan E. Chabarria Mark A. Bailey 《Journal of Natural History》2020,54(1-4):15-41
ABSTRACT Recent data from the mitochondrial genome reveal six lineages of Gulf Coast Waterdogs traditionally classified as Necturus beyeri. Here, we use patterns of colour and body size, along with previously published data, to reveal a large, heavily spotted phenotype with an unstriped larva possessing numerous white spots; we re-describe N. beyeri to correspond to this phenotype. We also reveal a small, weakly spotted phenotype possessing an unstriped larva lacking numerous white spots. This phenotype characterises the Apalachicola and Escambia lineages, which current evidence suggests are paraphyletic. We reject taxonomies that place these two lineages in N. lodingi because the type specimen of this species appears to be a melanistic member of N. beyeri. Therefore, we describe the Apalachicola and Escambia lineages as independent new species. http://ww.zoobank.org/urn:lsid:zoobank.org:act:C8508CCB-F54F-4DC8-B61D-56966A3F1CC8 http://www.zoobank.org/urn:lsid:zoobank.org:act:F044B2CC-55F0-4FFA-A312-9CAD9E73CD69 相似文献
53.
Damian Miles Bailey Peter Bärtsch Michael Knauth Ralf W. Baumgartner 《Cellular and molecular life sciences : CMLS》2009,66(22):3583-3594
Acute mountain sickness (AMS) is a neurological disorder that typically affects mountaineers who ascend to high altitude.
The symptoms have traditionally been ascribed to intracranial hypertension caused by extracellular vasogenic edematous brain
swelling subsequent to mechanical disruption of the blood–brain barrier in hypoxia. However, recent diffusion-weighted magnetic
resonance imaging studies have identified mild astrocytic swelling caused by a net redistribution of fluid from the “hypoxia-primed”
extracellular space to the intracellular space without any evidence for further barrier disruption or additional increment
in brain edema, swelling or pressure. These findings and the observation of minor vasogenic edema present in individuals with
and without AMS suggest that the symptoms are not explained by cerebral edema. This has led to a re-evaluation of the relevant
pathogenic events with a specific focus on free radicals and their interaction with the trigeminovascular system. (Part of
a multi-author review.) 相似文献
54.
Evershed RP Payne S Sherratt AG Copley MS Coolidge J Urem-Kotsu D Kotsakis K Ozdoğan M Ozdoğan AE Nieuwenhuyse O Akkermans PM Bailey D Andeescu RR Campbell S Farid S Hodder I Yalman N Ozbaşaran M Biçakci E Garfinkel Y Levy T Burton MM 《Nature》2008,455(7212):528-531
The domestication of cattle, sheep and goats had already taken place in the Near East by the eighth millennium bc. Although there would have been considerable economic and nutritional gains from using these animals for their milk and other products from living animals-that is, traction and wool-the first clear evidence for these appears much later, from the late fifth and fourth millennia bc. Hence, the timing and region in which milking was first practised remain unknown. Organic residues preserved in archaeological pottery have provided direct evidence for the use of milk in the fourth millennium in Britain, and in the sixth millennium in eastern Europe, based on the delta(13)C values of the major fatty acids of milk fat. Here we apply this approach to more than 2,200 pottery vessels from sites in the Near East and southeastern Europe dating from the fifth to the seventh millennia bc. We show that milk was in use by the seventh millennium; this is the earliest direct evidence to date. Milking was particularly important in northwestern Anatolia, pointing to regional differences linked with conditions more favourable to cattle compared to other regions, where sheep and goats were relatively common and milk use less important. The latter is supported by correlations between the fat type and animal bone evidence. 相似文献
55.
56.
This is the second of two articles describing the revision of The ONS classification of local and health authorities of Great Britain to take account of area changes in the 1990's. It presents local authorities in Great Britain as at April 1999 in terms of Families, Groups and Clusters, based on 37 socio-economic and demographic variables from the 1991 Census. Health authorities are presented in terms of Families and Groups only, based on the same variables. The previous article (in Population Trends 98) presented, for each local and health authority, up to four other authorities to which it is 'most similar'. 相似文献
57.
Williams ES Stap J Essers J Ponnaiya B Luijsterburg MS Krawczyk PM Ullrich RL Aten JA Bailey SM 《Nature genetics》2007,39(6):696-8; author reply 698-9
58.
Multilayers of phospholipid bimolecular leaflets 总被引:8,自引:0,他引:8
59.
Zusammenfassung Nachweis, dass die Aminosäure-Zusammensetzung der Hämolymphe vonSimuliumvenustum-Larven total 39.3±1.3 mg Amino N pro 100 ml enthält, wobei als hauptsächliche Ninhydrinpositive Bestandteile der Hämolymphe Alanin, Asparagin, Asparaginsäure, Dioxyphenylalanin, Äthanolanin, Glutaminsäure, Glutamin, Glycin, Histidin, Phenylalanin und Serin gefunden wurden, während nur kleine Mengen von Tyrosin, Halb-Cystin und Cystathion festgestellt wurden. 相似文献
60.
Summary Hypertrophy of nucleoli is associated with DNA synthesis in the hepatocytes of untreated rats just as it is in stimulated animals. Nucleolar enlargement is not a sufficient change to ensure that the parenchymal liver cell can make DNA.This work was supported by a grant from the National Cancer Institute. 相似文献