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The island fox is listed as a threatened species in California. A serologic survey of 194 island foxes (Urocyon littoralis) was conducted over the entire range of the species on the Channel Islands (California, USA). Antibody prevalence against canine adenovirus and canine parvovirus reached 97% and 59%, respectively, in some populations sampled. Antibody prevalence of canine herpesvirus, canine coronavirus, leptospirosis and toxoplasmosis were low. Antibodies against canine distemper virus were not detected.  相似文献   

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In 1945, Earl Sutherland (1915-1975) and associates began studies of the mechanism of hormone-induced glycogen breakdown in the liver. In 1956, their efforts culminated in the identification of cyclic AMP, an ancient molecule generated in many cell types in response to hormonal and other extracellular signals. Cyclic AMP, the original "second messenger," transmits such signals through pathways that regulate a diversity of cellular functions and capabilities: metabolic processes such as lipolysis and glycogenolysis; hormone secretion; the permeability of ion channels; gene expression; cell proliferation and survival. Indeed, it can be argued that the discovery of cyclic AMP initiated the study of intracellular signaling pathways, a major focus of contemporary biomedical inquiry. This review presents relevant details of Sutherland's career; summarizes key contributions of his mentors, Carl and Gerti Cori, to the knowledge of glycogen metabolism (contributions that were the foundation for his own research); describes the experiments that led to his identification, isolation, and characterization of cyclic AMP; assesses the significance of his work; and considers some aspects of the impact of cyclic nucleotide research on clinical medicine.  相似文献   

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We describe a new species of chondrophorine hydrozoan,Palaelophacmaea valentinei sp. nov., from the early Middle Cambrian part of the Cadiz Formation of the Marble Mountains of southeastern California. This find extends the stratigraphic range of this genus into the early Middle Cambrian and its geographic range into the western United States. We review various chondrophorine-like fossils and present a tentative chondrophorine phylogeny in light of this find.  相似文献   

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In the Namur-Dinant Basin (Belgium), the last Atrypida and Pentamerida originate from the top of the Upper Palmatolepis rhenana Zone (Late Frasnian). Within this biozone, their representatives belong to the genera Costatrypa, Desquamatia (Desquamatia), Radiatrypa, Spinatrypa (Spinatrypa), Spinatrypina (Spinatrypina?), Spinatrypina (Exatrypa), Waiotrypa, Iowatrypa and Metabolipa. No representative of these orders occurs within the Palmatolepis linguiformis Zone. The disappearance of the last pentamerids, mostly confined to reefal ecosystems, is clearly related to the end of the edification of the carbonate mounds; it precedes shortly the atrypid one. This event, resulting from a transgressive episode, which induces a progressive and dramatic deterioration of the oxygenation conditions, takes place firstly in the most distal zones of the Namur-Dinant Basin (southern border of the Dinant Synclinorium; Lower P. rhenana Zone). It is only recorded within the Upper P. rhenana Zone in the Philippeville Anticlinorium, the Vesdre area, and the northern flank of the Dinant Synclinorium. It would seem that the terebratulids were absent during the Famennian in this basin, probably due to inappropriate facies. Among the 13 species described or briefly discussed (Palmatolepis hassi to Upper P. rhenana zones), Pseudoatrypa godefroidi nov. sp. and Spinatrypina (Exatrypa) marmoris nov. sp. are proposed as new.  相似文献   

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A small hipparion from the Vallesian (early Late Miocene) of Northern Greece is studied. It is coming from the locality “Ravin de la Pluie” of the lower Axios valley, near Thessaloniki. Its characteristics as the small size, the short symphysis, the long snout, the high enamel plication, the well developed protostylid, the large m3 and the elongated m1-m3 series distinguish it from the other known eurasiatic small hipparions, allowed us to derive a new species,Hipparion macedonicum. It lived during Vallesian and can be used as a stratigraphic species for this period.  相似文献   

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Twelve microsatellite loci are presented for the biological control agent Chiasmia assimilis (Warren, 1899). These microsatellite loci were obtained through the construction of an enriched library, overcoming previous reported difficulties with obtaining microsatellites from other Lepidoptera due to the low frequency of microsatellites in their genomes.  相似文献   

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A new genus and species of catshark (Neoselachii, Carcharhiniformes, Scyliorhinidae) —Bavariscyllium tischlingeri n. gen. n. sp. — is described from the Late Jurassic (Tithonian) Plattenkalke of South Germany. The new taxon is known from a single articulated skeleton having the skull, the trunk and all of the fins preserved. The position of the first dorsal fin in relation to the pelvic fins and the dental morphology shows that the specimen belongs into the neoselachian family Scyliorhinidae. Two isolated tooth crowns from the Kimmeridgian of North Germany are identified asBavariscyllium sp. and represent the oldest unambigious fossil record of the Scyliorhinidae known so far.  相似文献   

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