Seismic evidence for water deep in Earth's upper mantle     

van der Meijde M  Marone F  Giardini D  van der Lee S 《Science (New York, N.Y.)》2003,300(5625):1556-1558

Water in the deep upper mantle can influence the properties of seismic discontinuities in the mantle transition zone. Observations of converted seismic waves provide evidence of a 20- to 35-kilometer-thick discontinuity near a depth of 410 kilometers, most likely explained by as much as 700 parts per million of water by weight.  相似文献   

Natural selection favors a newly derived timeless allele in Drosophila melanogaster     

Tauber E  Zordan M  Sandrelli F  Pegoraro M  Osterwalder N  Breda C  Daga A  Selmin A  Monger K  Benna C  Rosato E  Kyriacou CP  Costa R 《Science (New York, N.Y.)》2007,316(5833):1895-1898

Circadian and other natural clock-like endogenous rhythms may have evolved to anticipate regular temporal changes in the environment. We report that a mutation in the circadian clock gene timeless in Drosophila melanogaster has arisen and spread by natural selection relatively recently in Europe. We found that, when introduced into different genetic backgrounds, natural and artificial alleles of the timeless gene affect the incidence of diapause in response to changes in light and temperature. The natural mutant allele alters an important life history trait that may enhance the fly's adaptation to seasonal conditions.  相似文献   

Safety of percutaneous ultrasound-guided fine-needle aspiration of adrenal lesions in dogs: Perception of the procedure by radiologists and presentation of 50 cases     

Pascaline Pey  Alessia Diana  Federica Rossi  Jeremy Mortier  Ulrike Kafka  Stefanie Veraa  Anna Groth  Megan MacLellan  Chiara Marin  Federico Fracassi 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(2):626-635

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Ketamine‐dexmedetomidine combination and controlled mild hypothermia for the treatment of long‐lasting and super‐refractory status epilepticus in 3 dogs suffering from idiopathic epilepsy     

Daniela Gioeni  Federica Di Cesare  Elisa Silvia D'Urso  Vanessa Rabbogliatti  Giuliano Ravasio 《Journal of Veterinary Emergency and Critical Care》2020,30(4):455-460

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A brachiopod biotope associated with rocky bottoms at the shelf break in the central Mediterranean Sea: Geobiological traits and conservation aspects     

Lorenzo Angeletti  Simonepietro Canese  Frine Cardone  Giorgio Castellan  Federica Foglini  Marco Taviani 《水产资源保护:海洋与淡水生态系统》2020,30(2):402-411

1. In the Recent, brachiopods only seldom occur in benthic communities. A biotope dominated by Megerlia truncata was identified in 2013 by exploration of the south‐easternmost Adriatic margin by Remotely Operated Vehicle (ROV).
2. Emerging rocky substrates next to the shelf break at approximately 120 m appear intensively exploited by this eurybathic rhynchonelliformean brachiopod, attaining a population of more than 300 individuals per m².
3. Calcareous red algae are almost ubiquitous at this site and preferentially encrust sectors of the substrate where brachiopods are minimal.
4. This Megerlia biotope is a novel finding for this part of the Mediterranean Sea, similar to a situation previously observed in the Western Basin, off the Mediterranean French coast.
5. It is proposed that this remarkable brachiopod biotope and the adjacent rhodolith bed are considered important for conservation management.

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Anti-inflammatory, antioxidant and antifungal furanosesquiterpenoids isolated from Commiphora erythraea (Ehrenb.) Engl. resin     

Fraternale D  Sosa S  Ricci D  Genovese S  Messina F  Tomasini S  Montanari F  Marcotullio MC 《Fitoterapia》2011,82(4):654-661

The topical anti-inflammatory, free radical scavenging and antifungal activities of essential oils and extracts of Commiphora erythraea (Ehrenb.) Engl. resin were investigated. The hexane extract significantly inhibited oedema when applied topically in Croton oil-induced ear oedema assay in mice. The same extract showed antioxidant activity in DPPH radical scavenging assay. A bioguided separation of the hexane extract led to the isolation of furanosesquiterpenoids 1 and 2 that showed a weak antifungal activity, while compounds 3-5 resulted to be antioxidant (EC₅₀ 4.28, 2.56 and 1.08 mg/mL, respectively) and anti-inflammatory (30, 26 and 32% oedema reduction, respectively).  相似文献   

Putative embryonic stem cell lines from pig embryos   总被引：2，自引：0，他引：2  

Vackova I  Ungrova A  Lopes F 《The Journal of reproduction and development》2007,53(6):1137-1149

Embryonic stem cells (ES cells) were first established in the mouse, and they represent a population of pluripotent, undifferentiated cells derived from early embryos that is capable of proliferating without any limitation in an undifferentiated state. These cells retain the ability to differentiate in vitro or in vivo into derivates of all three germ layers, and when injected into blastocysts, they can participate in the formation of all tissues, including gonads (germ-line chimeras). It is possible to transfect them with a gene of interest, and the resulting transgenic cell lines can also be used for production of chimeras. Unfortunately, mammalian germ-line chimeras that can carry an inserted gene into their progeny have only been produced in the mouse. Logically, before application of stem cell therapies into a human medicine, it is necessary to verify the efficiency and safety of these methods with an acceptable animal model. The pig is currently used as a very convenient animal for pre-clinical applications, and therefore establishment of porcine ES cell lines is highly needed; unfortunately, no convincing ES cell lines have been produced in this species (and other domestic animals) to date. In this article, we discuss the recent advances in this field, especially oriented on possible reasons and obstacles why derivation of porcine ES cell lines is still unsuccessful.  相似文献   

What is your diagnosis? Metastatic bone tumor     

James DC  Morandi F  Marioni-Henry K 《Journal of the American Veterinary Medical Association》2007,230(10):1463-1464

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COMPUTED TOMOGRAPHIC FEATURES OF PHARYNGEAL NEOPLASIA IN 25 DOGS          下载免费PDF全文

Gregorio Carozzi  Alessandro Zotti  Monica Alberti  Federica Rossi 《Veterinary radiology & ultrasound》2015,56(6):628-637

Computed tomography (CT) is commonly used to investigate head tumors in dogs, however little information is available for lesions of the pharyngeal area. The purpose of this multicentric, retrospective, cross‐sectional study was to describe the CT findings in a sample of dogs with pathologically confirmed pharyngeal neoplasia and determine whether any CT features allowed differentiation of tumor type. Location of lesions, size and shape, margins, relationship with surrounding structures and vessels, attenuation characteristics and enhancement pattern, regional lymph node changes, and presence of metastasis were recorded by three observers (1 DECVDI). The effect of final diagnosis on each CT feature was tested. A total of 25 dogs were included: 15 with carcinomas, five sarcomas, four melanomas, and one lymphoma. The oropharynx and laryngopharynx were more frequently involved. Among tumor groups, lesions were of similar size, irregularly shaped, had ill‐defined margins, and had moderate‐to‐marked heterogeneous contrast enhancement. Lysis of hyoid bones was recorded in two carcinomas and infiltration of the lingual artery occurred in one case. Marked medial retropharyngeal lymphoadenomegaly was recorded in 11 of 14 carcinomas, in all sarcomas and in two of four melanomas. The single lymphoma case showed ill‐defined thickening of the oropharyngeal and laryngeal wall with retropharyngeal and mandibular lymphadenomegaly. Lung metastases were found in two of five sarcomas and two of four melanomas. Findings from the current study did not support the hypothesis that CT features could be used to predict pharyngeal tumor type in dogs. However, CT was helpful for determining mass extension, lymph node involvement, and distant metastatic spread.  相似文献   

High human density in the irreplaceable sites for African vertebrates conservation     

Carlo Rondinini  Federica Chiozza 《Biological conservation》2006,133(3):358-363

The identification of priority sites that ensure the achievement of conservation goals is key to direct conservation efforts. An estimation of the level of vulnerability of each priority area allows the identification of sites that need urgent conservation action. We present a systematic reserve selection for 1654 African mammals and amphibians that uses habitat suitability models as estimates of the area occupied by each species. These are based on the geographic range and habitat preferences for each species, which we collected in the framework of the World Conservation Union (IUCN) Global Amphibian Assessment and IUCN Global Mammal Assessment. Our results showed that in addition to existing protected areas, approximately 2.8 million km² of land is irreplaceable to achieve the protection of 10% of the area occupied by all amphibians and mammals. This figure is higher than previous estimates from other studies. Most irreplaceable sites are located in the sub-Saharan region. More than half (55%) of the irreplaceable sites have high human population density; for only 17% the human population density is low. African amphibians and mammals have therefore to be conserved in densely populated areas where innovative management policies will be required to accommodate conservation successfully.  相似文献