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Although no precise figures are available, many congenital brain lesions arise from intrauterine disruption, frequently due to obstetric complications. The most common entities include intracranial hemorrhage, ischemic lesions, thrombosis of venous vessels and infections. Accurate prenatal diagnosis is possible in many of these cases. However, the findings may be subtle, particularly in the early stage of the disruptive process. Identification of these conditions requires therefore specific expertise, the combination of fetal neurosonography and magnetic resonance, and frequently there is a need for serial examinations. Targeted diagnostic imaging should be offered to obstetric patients with conditions predisposing to prenatal cerebral insults. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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Food and Environmental Virology - Kinetics of hepatitis A virus (HAV) accumulation and depuration from mussels (Mytilus galloprovincialis) was studied in an experimental depuration system....  相似文献   
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Congenital ovarian cysts are a pathological condition which can be diagnosed in utero by ultrasound. We report 14 consecutive diagnoses of fetal ovarian cysts, obtained in the second and third trimesters of pregnancy. Congenital ovarian cysts have almost invariably a good prognosis, and no change in the standard obstetrical management is required. However, the evolution of the disease in utero is extremely variable. The cyst may increase in size, decrease or even disappear, or undergo complications such as torsion and rupture, which may carry some risks to the fetus. When a fetal ovarian cyst is detected, serial ultrasound examinations should be performed. If one of the above complications is suspected, the option of prompt caesarean section should be considered.  相似文献   
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Sardinia hosts 186 endemic plant species and represents an important centre for Mediterranean biodiversity. In view of the threats facing its flora, 27 terrestrial vascular plants have been listed in international regulations and 124 sites designated for species and habitat conservation. This study analyses gaps in the Natura 2000 network and the current and future distribution of four representative plants. Each plant population was georeferenced and the effectiveness of the Natura 2000 network was compared according to conservation status and distribution. Future species distributions were modelled by considering current climatic conditions and future scenarios. In apparent discordance with other results, we found that the Natura 2000 network represents most plant species well. This research shows a forward-looking survey on the regional effectiveness of protection measures which led us to confirm the need to enhance the current state of the Natura 2000 network by implementing local legislation and regulations.  相似文献   
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To understand the consequences of the invasion of the nonnative rainbow trout Oncorhynchus mykiss on the native marble trout Salmo marmoratus, we compared two distinct headwater sectors where marble trout occur in allopatry (MTa) or sympatry (MTs) with rainbow trout (RTs) in the Idrijca River (Slovenia). Using data from field surveys from 2002 to 2009, with biannual (June and September) sampling and tagging from June 2004 onwards, we analyzed body growth and survival probabilities of marble trout in each stream sector. Density of age-0 in September over the study period was greater for MTs than MTa and very similar between MTs and RTs, while density of trout ≥age-1 was similar for MTa and MTs and greater than density of RTs. Monthly apparent survival probabilities were slightly higher in MTa than in MTs, while RTs showed a lower survival than MTs. Mean weight of marble and rainbow trout aged 0+ in September was negatively related to cohort density for both marble and rainbow trout, but the relationship was not significantly different between MTs and MTa. No clear depression of body growth of sympatric marble trout between sampling intervals was observed. Despite a later emergence, mean weight of RTs cohorts at age 0+ in September was significantly higher than weight of both MTs and MTa. The establishment of a self-sustaining population of rainbow trout does not have a significant impact on body growth and survival probabilities of sympatric marble trout. The numerical dominance of rainbow trout in streams at lower altitudes seem to suggest that while the low summer flow pattern of Slovenian streams is favorable for rainbow trout invasion, the adaptation of marble trout to headwater environments may limit the invasion success of rainbow trout in headwaters.  相似文献   
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Nowadays, high-time resolved aerosol studies are mandatory to better understand atmospheric processes, such as formation, removal, transport, deposition or chemical reactions. This work focuses on PM10 physical and chemical characterisation with high-time resolution: elements (from Na to Pb), ions and OC/EC fractions concentration were determined during two weeks in summer and two in winter 2006 with 4-hours resolution. Further measurements aimed at hourly elemental characterisation of fine and coarse fractions and at the determination of particles number concentration in the 0.25-32 microm size range in 31 bins. The chemical mass closure was carried out in both seasons, enhancing intra-day differences in PM10 composition. In Milan, the highest contribution came from organic matter (34% and 33% in summer and winter, respectively); other important contributors were secondary inorganic compounds (16% and 24% in summer and winter, respectively) and, in summer, crustal matter (14%). Temporal trends showed strong variations in PM10 composition during contiguous time-slots and diurnal variations in different components contribution were identified. Moreover, peculiar phenomena, which would have hardly been detected with 24-hours samplings, were evidenced. Particles removal due to precipitations, aerosol local production and long range transport were studied in detail.  相似文献   
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A significant percentage of bisphenol A and nonylphenol removal in municipal wastewater treatment plants relies on biodegradation. Nonetheless, incomplete information is available concerning their degradation pathways performed by microbial communities in activated sludge systems. Hydroquinone dioxygenase (HQDO) is a specific degradation marker enzyme, involved in bisphenol A and nonylphenol biodegradation, and it can be produced by axenic cultures of the bacterium Sphingomonas sp. strain TTNP3. Proteomics, a technique based on the analysis of microbial community proteins, was applied to this strain. The bacterium proteome map was obtained and a HQDO subunit was successfully identified. Additionally, the reliability of the applied proteomics protocol was evaluated in activated sludge samples. Proteins belonging to Sphingomonas were searched at decreasing biomass ratios, i.e. serially diluting the bacterium in activated sludge. The protein patterns were compared and Sphingomonas proteins were discriminated against the ones from sludge itself on 2D-gels. The detection limit of the applied protocol was defined as 10?3 g TTNP3 g?1 total suspended solids (TSSs). The results proved that proteomics can be a promising methodology to assess the presence of specific enzymes in activated sludge samples, however improvements of its sensitivity are still needed.  相似文献   
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