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To characterise some traits of the life strategies of Polycheles typhlops, a deep-sea small lobster usually encountered as by-catch within deep trawls in the Southern Tyrrhenian Sea (Mediterranean Sea), we analysed the biochemical composition of the caudal muscles of 49 specimens collected in March and April 2007. Differences in the biochemical composition between females and males were weak, but relevant differences in protein (>90% of the organic C) and lipid (4–6%) contents were observed between developmental stages both in females and males. These differences are likely to be related to different food items and/or to the metabolic shifts associated with their reproduction. We argue that this deep-sea lobster could cover a relevant role in the meso-pelagic food webs and attract future commercial interest.  相似文献   
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In this paper we report the fetal loss rate in relation to both maternal and gestational age in 1764 pregnant women who underwent transabdominal chorionic villus sampling (TA-CVS) between January 1986 and August 1990. The fetal loss rate, considered as a proportion of continuing pregnancies, decreased with advancing gestational age at sampling from 4.3 per cent before 9 weeks to 0.4 per cent at or after 13 weeks, the difference being statistically significant (p <0.025). The fetal loss rate increased from 1.6 per cent in women under 30 to 2.4 per cent in women of 40 years or over, but the difference was not statistically significant. Considering that the total fetal loss rate before 28 weeks' gestation was on average 1.91 percent (1.3 per cent under 35 years and 2.8 per cent in women of 35 or over), we believe that TA-CVS is a safe and effective technique for prenatal diagnosis of genetic diseases.  相似文献   
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The water-soluble fraction (WSF) of petroleum contains a mixture of polycyclic aromatic hydrocarbons, volatile hydrocarbons, phenols, and heterocyclic compounds, considered deleterious to aquatic biota. Marine “pejerrey” Odontesthes argentinensis (Teleostei: Atherinopsidae) has a great commercial importance in local fisheries and a high potential for aquaculture. The aim of this study was to evaluate the histopathological effects in “pejerrey” larvae exposed to different concentrations of petroleum WSF. The chronic toxicity test was conducted with newly hatched larvae exposed for 21 days to sublethal concentrations of WSF (2.5, 5, 10, and 20 % of WSF), plus one control. Survival and growth were significantly lower in the highest concentration. Several histopathological changes were found in the gills (e.g., hyperplasia, aneurisms, edema, and necrosis), kidney (e.g., nuclear alterations, decrease in the hematopoietic cells), and liver (e.g., hypertrophy, karyorrhexis, and karyopyknosis). An index of branchial lesion was proposed to standardize gill lesions to different pollutants.  相似文献   
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Genuine fossils with exquisitely preserved plumage from the Late Jurassic and Early Cretaceous of northeastern China have recently revealed that bird-like theropod dinosaurs had long pennaceous feathers along their hindlimbs and may have used their four wings to glide or fly. Thus, it has been postulated that early bird flight might initially have involved four wings (Xu et al. Nature 421:335–340, 2003; Hu et al. Nature 461:640–643, 2009; Han et al. Nat Commun 5:4382, 2014). Here, we describe Serikornis sungei gen. et sp. nov., a new feathered theropod from the Tiaojishan Fm (Late Jurassic) of Liaoning Province, China. Its skeletal morphology suggests a ground-dwelling ecology with no flying adaptations. Our phylogenetic analysis places Serikornis, together with other Late Jurassic paravians from China, as a basal paravians, outside the Eumaniraptora clade. The tail of Serikornis is covered proximally by filaments and distally by slender rectrices. Thin symmetrical remiges lacking barbules are attached along its forelimbs and elongate hindlimb feathers extend up to its toes, suggesting that hindlimb remiges evolved in ground-dwelling maniraptorans before being co-opted to an arboreal lifestyle or flight.  相似文献   
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Petroleum hydrocarbons are considered one of the main organic chemicals found in water bodies. In the present study, the median lethal concentration (LC50) was estimated for mullet Mugil liza after acute exposure to petroleum water-soluble fraction (PWSF). Furthermore, histopathological studies and micronuclei frequency were also performed in order to observe deleterious effects of medium-term exposition to PWSF. Mullets (25?±?2.3 g) were exposed to chronic concentrations (1.7, 3.5 and 7 % of PWSF), plus the control group, for 14 and 7 days of clearance time. Throughout the experimental period (1, 4, 14 and 21 days), blood samples were collected for analysis of micronucleus (MN) and liver and gills for histopathological study. For these procedures, seven fish were sampled per concentration tested. The LC50-96 h was estimated at 37.5 % of the PWSF. The time required for MN induction was 96 h of exposure. The time of clearance was sufficient to achieve a MN frequency similar to that of the control group. Histopathological studies showed severe changes in the gill and liver tissues. The most relevant histopathology in the gills was telangiectasia. Hepatic histopathology such as cholestasis, dilated sinusoids and inflammatory infiltrates were commonly described. The MN test and histological study effectively detected damages caused by medium-term exposition to the PWSF, and despite the toxicity, a few days without exposure can minimize PWSF genotoxicity in juveniles of M. liza.  相似文献   
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In the isolated Aluoi Valley of central Viet Nam, very high levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were measured in soil, fish fat, duck fat, pooled human blood and breast milk samples collected from A So village between 1996 and 1999. The village was situated on a former military base occupied by US Special Forces between 1963 and 1966. TCDD was a contaminant of the herbicide "Agent Orange", aerially sprayed in the valley between 1965 and 1970, and stored at the A So base. Measured levels were lower near the sites of two other former US bases in the valley which had been occupied for shorter periods of time. In areas where Agent Orange had been applied by low-flying aircraft, levels of TCDD in soil, food and human samples were elevated, but lower than those near the three former US bases. We confirm the apparent food chain transfer of TCDD from contaminated soil to cultured fish pond sediments to fish and duck tissues, then to humans as measured in whole blood and breast milk. We theorize that the Aluoi Valley is a microcosm of southern Viet Nam, where numerous reservoirs of TCDD exist in the soil of former military installations south of the former demilitarized zone. Large quantities of Agent Orange were stored at many sites, used in ground and aerial applications, and spilled. TCDD, through various forms of soil disturbance, can be mobilized from these reservoirs after decades below the surface, and subsequently, introduced into the human food chain.  相似文献   
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Due to the bad state of conservation, “Palazzo Governi”, a seventeenth-century building located in the old town district of “Stampace” in Cagliari (Sardinia, Italy), was subjected to restoration. Thus, according to the Italian Law n. 1089, the main façade colour must be reproduced, and therefore, its identification was required. The available samples looked fairly degraded, in particular as an easy plaster to crumble; so, some other analyses able to identify the degradation cause were performed. Two different approaches were adopted to attain the first goal, the visual colour assessment by a sensory panel (subjective) and the instrumental measurement by colorimetry (objective). Ion chromatography and inductively coupled plasma–optical emission spectroscopy analyses, as well as conductivity and pH measurements, were performed to evaluate the presence of water-soluble salts inside the plaster, as possible cause of degradation; the binder/aggregate ratio was also evaluated. A full mineralogical and petrographic characterisation of the materials constituting the samples, as well as the identification of their stratigraphy and some other morphologic and structural features suitable to highlight eventual forms of degradation, were performed by optical microscopy. Scanning electron microscopy coupled to X-ray microanalysis was been also used in order to confirm and/or to integrate data obtained by optical microscopy. The samples have been compared with two samples coming from two other buildings, also located in Sardinia, that looked in good conservation state. The results evidenced that the causes of degradation come from a high salt (especially sulphate) content and a scarce presence of binder in the plaster that can be imputed to a wrong initial composition and/ or to a leaching by acidic rain.  相似文献   
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Atlantic blue fin tuna (Thunnus thynnus) is a species of great importance for Mediterranean Sea area, from both ecological and commercial points of view. The scientific literature reports few data on the contamination of this fish by emerging organic compounds such as perfluorinated alkylated substances(PFASs) and phthalates, being the latter never been studied in tuna. This study therefore investigated the presence of the PFASs perfluorooctane sulphonate (PFOS) and perfluoroctanoic acid (PFOA) and the phthalate di-2-ethylhexyl phthalate (DEHP), also monitored by its metabolite mono-2-ethylhexyl phthalate(MEHP), to assess both the state of contamination of Atlantic bluefin tuna specimen and the risk due to the toxicity of these compounds for human consumption. While PFOA was never found, detectable levels of PFOS (0.4–1.88 ng/g), DEHP (9–14.62 ng/g) and MEHP (1.5–6.30 ng/g) were found. The results were elaborated relating the accumulation to the size and age of the individuals and showed a correlation between the levels of different pollutants investigated.  相似文献   
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