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41.
Capillaria (Procapillaria) navoneae n. sp. is described from the congrid fish Conger orbignianus from waters off Mar del Plata, Argentina (38 degrees 08'S, 57 degrees 32'W) (prevalence 29.17%, mean intensity +/- SD 6.07 +/- 6.59). The new species is assigned to the subgenus Procapillaria Moravec, 1987, despite the absence of vulvar appendages in gravid females. Of the 3 species so far known in the subgenus, the new one most closely resembles C. (P.) margolisi, from which it is distinguished by lacking a medial expansion in the spicule and a slightly elevated anterior lip of vulva, and by having a shorter esophagus, a larger number of stichocytes, and a shorter tail. 相似文献
42.
In total, 17 specimens of Conger orbignianus Valenciennes, 1847 from waters off Mar del Plata, Argentina (38 degrees 08'S, 57 degrees 32'W) were examined for parasitic nematodes. A new nematode species, Cucullanus pedroi n. sp., is described (prevalence 76.5%, x intensity +/- SD = 3.8 +/- 2.7). The new species closely resembles some species parasitizing other anguilliform fishes; however, it can be distinguished from most of its congeners by the distribution pattern of caudal papillae (particularly fourth and eight pairs) and phasmids. Those congeners with similar pattern of papillae differ from the new species by the length of the spicules and gubernaculum and by the position of the excretory pore and deirids. 相似文献
43.
Sigot-Luizard M. F. Lanfranchi M. Duval J. L. Benslimane S. Sigot M. Guidoin R. G. King M. W. 《In vitro cellular & developmental biology. Plant》1986,22(5):234-240
Summary To avoid the need to preclot porous polyester (Dacron) vascular prostheses, we have proposed the use of a protein coating
that will promote the growth and adhesion of endothelial cells. This study assessed the relative advantages of coating woven,
knitted, and velour polyester fabrics with albumin, collagen, and a albumin-collagen mixture after preservation in saline
or drying by a commercial dehydration process. Preclotted fabrics were used as controls. The cytocompatibility of these biopolymers
was measured by an organotypic culture technique which relies on the migration of chick embryonic endothelial cells. After
7 d of culture the cytocompatibility was quantified by counting the cells in the area of migration and the morphology of the
endothelial cells was observed by scanning electron microscopy. In general, the knitted and velour fabrics showed superior
compatibility than the woven one. The results confirmed that collagen, either alone or combined with albumin, provides in
most cases a more cytocompatible surface than albumin alone. A cell morphology most closely resembling that of natural arterial
endothelial cells was observed on the albumin-collagen substrate.
This study was supported by INSERM Grant C. R. L. 82 30 16, the Medical Research Council of Canada, and the Canadian Heart
Foundation. 相似文献
44.
45.
A new species, Paracapillaria argentinensis n. sp., is described from the pinguipedid fish Pinguipes brasilianus Cuvier, 1829 from waters off Mar del Plata, Argentina (38 degrees 08'S, 57 degrees 32'W) (prevalence 22.2%; mean intensity +/- SD, 4.42 +/- 5.19). The new species is assigned to the subgenus Paracapillaria Moravec, 1987. Of the 10 species so far known in the subgenus, the new species more closely resembles P. (P.) plectroplites, from which it is distinguished by having a spicule with an expanded anterior end and a slender medial section. A similar spicular morphology is observed in P. (P.) epinephell; however, it shows shorter spicules and a highly reduced caudal bursa. This is the first record of Paracapillaria in the southwestern Atlantic Ocean. 相似文献
46.
47.
48.
Age-dependent genetic effects on a secondary sexual trait in male Alpine ibex, Capra ibex 总被引:1,自引:0,他引:1
Von Hardenberg A Bassano B Festa-Bianchet M Luikart G Lanfranchi P Coltman D 《Molecular ecology》2007,16(9):1969-1980
Secondary sexual traits, such as horns in ungulates, may be good indicators of genetic quality because they are costly to develop. Genetic effects on such traits may be revealed by examining correlations between multilocus heterozygosity (MLH) and trait value. Correlations between MLH and fitness traits, termed heterozygosity-fitness correlations (HFC), may reflect inbreeding depression or associative overdominance of neutral microsatellite loci with loci directly affecting fitness traits. We investigated HFCs for horn growth, body mass and faecal counts of nematode eggs in wild Alpine ibex (Capra ibex). We also tested if individual inbreeding coefficients (f') estimated from microsatellite data were more strongly correlated with fitness traits than MLH. MLH was more strongly associated with trait variation than f'. We found HFC for horn growth but not for body mass or faecal counts of nematode eggs. The effect of MLH on horn growth was age-specific. The slope of the correlation between MLH and yearly horn growth changed from negative to positive as males aged, in accordance with the mutation accumulation theory of the evolution of senescence. Our results suggest that the horns of ibex males are an honest signal of genetic quality. 相似文献
49.
Mario Chiari Nicola Ferrari Daniele Giardiello Dominga Avisani Mariagrazia Zanoni Giovanni Loris Alborali Paolo Lanfranchi Vittorio Guberti Capucci Lorenzo Lavazza Antonio 《European Journal of Wildlife Research》2014,60(6):891-896
The progressive decline in the hare population across Europe has been associated with the occurrence of European brown hare syndrome (EBHS), a highly contagious disease considered endemic in all European countries. This study aimed to evaluate the in-field temporal dynamics of European brown hare syndrome virus (EBHSV) infection in wild European brown hares (Lepus europaeus) and to test the influence of population density on EBHS seroprevalence. A total of 512 blood samples were collected from free ranging hares captured for restocking in seven different areas of the province of Brescia (Northern Italy) during seven consecutive years (2006–2013) and tested using a competitive ELISA. A generalized linear mixed model estimated the yearly effects of population density on EBHS prevalence. Of the 512 tested, 344 (67.2 %) tested positive for EBHSV antibodies, with the annual seroprevalence ranging from 94.3 to 35.8 %. The prevalence was 3.303 times higher in areas with a density of over 15 hares/km2 and declined over the years. The results indicate the ongoing transmission of the virus in the tested brown hare population. Since the eradication of EBHS in a wild population is not feasible, a strategy aimed at promoting the endemic stability of the virus through density-dependent mechanisms could be applied; however, this seems more difficult in practice than in theory and would most likely require a very high density of brown hares. 相似文献
50.
During the period 1987-1999, 119 wolf cadavers were examined and checked for the presence of Echinococcus granulosus. All the animals were retrieved along the whole Apennines range of distribution of the species in Italy and most of them were illegally killed. Eighteen wolves resulted positive (15%). The mean intensity was 697.5. The force of infection for prevalence was 8.2 year(-1). The prevalence of the parasite was significantly and positively influenced by the local prevalence of cystic echinococcosis (CE) in sheep. Mean intensity was significantly and positively influenced by both the age of the wolf and the prevalence of CE in sheep. A deterministic model was used in order to simulate a purely theoretical sylvatic cycle of the parasites having the wolf as the only definitive host with 15% of prevalence. The expected prevalence of CE in wild intermediate species ranges between 10% and 25%. This prevalence overlaps the one observed in sheep. Even if both the wolf and the wild ungulate populations are increasing, the wolf still acts as a part of the main dog-sheep cycle of the parasite. 相似文献