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661.
The nuclear 28S rRNA and the mitochondrial COII gene were used to establish phylogenetic relationships among species of the family Neanuridae, with special emphasis on species of the subfamily Neanurinae. Phylogenetic analysis was conducted using genetic distances, parsimony and likelihood methods. The D3-D5 fragment of the rRNA gene was very conserved, both in sequence and in secondary structure features. This fragment supplied little information on relationships at this level. The phylogenetic reconstruction based on 1st and 2nd codon positions of the COII gene was partly in accordance with morphological data, but it was discordant for the placement of some species. Relationships among the subfamilies Frieseinae, represented by the Antarctic species Friesea grisea, Pseudachorutinae and Neanurinae were uncertain. The subfamily Neanurinae and its tribes Neanurini and Paleonurini were shown as monophyletic taxa. Relationships between three species of the genus Bilobella were in accordance with morphological and biochemical data. Relationships between genera within the Neanurini were more controversial. In accordance with morphological hypotheses, a basal position of Thaumanura was suggested, but the molecular data placed Neanura muscorum in a derived position, in sharp contrast with morphological evidence. A close relationship was suggested between Deutonura conjuncta, Cansilianura malatestai and Lathriopyga longiseta. The disagreement between molecular and morphological data suggests that one or both data sets might be affected by a certain degree of homoplasy and that these data should be interpreted with caution in phylogenetic reconstructions. 相似文献
662.
Vanhaereny M d'Errico F Stringer C James SL Todd JA Mienis HK 《Science (New York, N.Y.)》2006,312(5781):1785-1788
Perforated marine gastropod shells at the western Asian site of Skhul and the North African site of Oued Djebbana indicate the early use of beads by modern humans in these regions. The remoteness of these sites from the seashore and a comparison of the shells to natural shell assemblages indicate deliberate selection and transport by humans for symbolic use. Elemental and chemical analyses of sediment matrix adhered to one Nassarius gibbosulus from Skhul indicate that the shell bead comes from a layer containing 10 human fossils and dating to 100,000 to 135,000 years ago, about 25,000 years earlier than previous evidence for personal decoration by modern humans in South Africa. 相似文献
663.
Habashi JP Judge DP Holm TM Cohn RD Loeys BL Cooper TK Myers L Klein EC Liu G Calvi C Podowski M Neptune ER Halushka MK Bedja D Gabrielson K Rifkin DB Carta L Ramirez F Huso DL Dietz HC 《Science (New York, N.Y.)》2006,312(5770):117-121
Aortic aneurysm and dissection are manifestations of Marfan syndrome (MFS), a disorder caused by mutations in the gene that encodes fibrillin-1. Selected manifestations of MFS reflect excessive signaling by the transforming growth factor-beta (TGF-beta) family of cytokines. We show that aortic aneurysm in a mouse model of MFS is associated with increased TGF-beta signaling and can be prevented by TGF-beta antagonists such as TGF-beta-neutralizing antibody or the angiotensin II type 1 receptor (AT1) blocker, losartan. AT1 antagonism also partially reversed noncardiovascular manifestations of MFS, including impaired alveolar septation. These data suggest that losartan, a drug already in clinical use for hypertension, merits investigation as a therapeutic strategy for patients with MFS and has the potential to prevent the major life-threatening manifestation of this disorder. 相似文献
664.
Fogassi L Ferrari PF Gesierich B Rozzi S Chersi F Rizzolatti G 《Science (New York, N.Y.)》2005,308(5722):662-667
Inferior parietal lobule (IPL) neurons were studied when monkeys performed motor acts embedded in different actions and when they observed similar acts done by an experimenter. Most motor IPL neurons coding a specific act (e.g., grasping) showed markedly different activations when this act was part of different actions (e.g., for eating or for placing). Many motor IPL neurons also discharged during the observation of acts done by others. Most responded differentially when the same observed act was embedded in a specific action. These neurons fired during the observation of an act, before the beginning of the subsequent acts specifying the action. Thus, these neurons not only code the observed motor act but also allow the observer to understand the agent's intentions. 相似文献
665.
Paolo Guidetti Piero Addis Fabrizio Atzori Simona Bussotti Antonio Cal Alessandro Cau Jean‐Michel Culioli Giuseppe De Lucia Antonio Di Franco Manfredi Di Lorenzo Maria Cristina Follesa Vittorio Gazale Giorgio Massaro Francesco Mura Augusto Navone David Pala Pier Augusto Panzalis Antonio Pusceddu Alberto Ruiu Angelo Cau 《水产资源保护:海洋与淡水生态系统》2019,29(4):537-545
666.
Modelling giant red shrimp larval dispersal in the Sardinian seas: density and connectivity scenarios 下载免费PDF全文
Francesco Palmas Antonio Olita Piero Addis Roberto Sorgente Andrea Sabatini 《Fisheries Oceanography》2017,26(3):364-378
The connectivity and three‐dimensional (3D) dispersion of the larvae of giant red shrimp, potentially released from known spawning areas along the Sardinia slope in the western Mediterranean Sea, were assessed using Lagrangian simulations forced by a 3D submesoscale permitting a regional ocean model. Biophysical simulations using the hydrodynamic conditions of the year 2012 were run to track propagules released from known spawning areas during the spawning period (May to September). Passive transport (PT) and vertical migration (VM) scenarios were tested, each with two possible pelagic larval durations (PLDs) of 21 or 42 days. Dispersion of propagules in the PT and VM scenarios differed in terms of travelled distance, export out of the domain (larger for VM), and depth distribution (shallower and bimodal for VM due to the larger variability of encountered currents). Connectivity patterns were investigated among eight release areas, and four predetermined Eco‐Regions, and results showed strong connectivity among the North‐Western (NW), Western (W), and Southern (S) regions of Sardinia, whereas the Eastern region was more segregated. Differences in connectivity patterns among scenarios were related mainly to the tendency of greater retention of propagules in the release area for the PT scenarios. This finding, together with existing hypotheses of vertical migration likely occurring during first egg‐larval phases, suggest that the VM scenarios are the most probable of the two hypotheses tested. Strong connectivity between the W and S sides of Sardinia and the relative isolation of the E side could have significant implications for the protection of this important resource. 相似文献
667.
Siotto Michela Tosin Maurizio Degli Innocenti Francesco Mezzanotte Valeria 《Water, air, and soil pollution》2011,217(1-4):245-254
Water, Air, &; Soil Pollution - In the last 20&;nbsp;years, a new generation of materials was developed: the biodegradable plastics. They reduce the accumulation of plastic in the environment... 相似文献
668.
Polygalacturonase inhibiting proteins (PGIPs) are leucine-rich repeat glycoproteins, localized in the cell wall of most plant species, capable of countering the activity of endo-polygalacturonases (endo-PGs) produced by phytopathogenic fungi. The PGIP from Allium porrum leaves was analysed to ascertain the presence of different molecular forms of PGIP. Leek PGIP was separated into two fractions: a soluble and an ionically wall-bound PGIP, each of which was then purified by cation-exchange chromatography. Two and three peaks of PGIP activity were obtained, respectively. PGIP isoforms contained in each peak were separated by isoelectrofocusing (IEF) on a polyacrylamide gel. Following the separation, the gel was first overlaid with sodium polygalacturonate and then treated with the endo-PG from either Sclerotinia sclerotiorum, Fusarium moniliforme or Botrytis aclada. The endo-PG(s) hydrolyse the overlaid substrate except where active inhibitors are present. The presence of PGIPs is revealed by ruthenium red staining of the nonhydrolysed substrate. Each PGIP peak following IEF separation revealed several PGIP isoforms with pIs between 5.0 and 7.0. More than 20 isoforms were detected in total, with considerable differences in their inhibitory activity. While similar PGIP isoform patterns were obtained by developing the IEF gels with the endo-PGs of S. sclerotiorum and B. aclada, less intense PGIP bands were observed with the endo-PG from B. aclada, consistent with inhibition assays performed in solution. The endo-PG from F. moniliforme, which is not inhibited at all by leek PGIP in solution, consistently showed no PGIP band on the gel assay. 相似文献
669.
Barbara Lamagna Orlando Paciello† Manuela Ragozzino Serenella Papparella† Serena Montagnaro‡ Francesco Lamagna 《Veterinary ophthalmology》2009,12(2):97-101
Objective To describe a case of a conjunctivo-corneal mass in a cat associated with acid-fast bacilli.
Methods A 2-year-old female black European Short-Hair cat, living outdoors in a suburban environment in Italy, was referred for evaluation of a nodular, vascularized mass of 2 weeks duration. The mass involved the dorsal bulbar conjunctiva at the temporal canthus of OS and invaded the sclera and cornea. Routine ophthalmic and systemic examination, serologic testing, cytology and histology of the mass were performed. Mycobacterium specific polymerase chain reaction (PCR) of variable regions 1, 2 and 3 of the 16S ribosomal RNA (rRNA) gene was also performed.
Results Neutrophils, lymphocytes, macrophages and giant cells with intracytoplasmic acid-fast bacilli were seen on cytological examination. The histological examination confirmed the presence of a granulomatous lesion with acid-fast bacilli within macrophages. Bacteriological culture of the material from the lesion was negative for Mycobacterium spp. Mycobacterium 16S rRNA gene specific PCR was positive.
A diagnosis of feline leprosy was made. The owners refused any treatment, and 1 year later the lesion was still present.
Conclusions Veterinary ophthalmologists should be aware of conjunctivo-corneal leproma as an unusual symptom of leprosy. 相似文献
Methods A 2-year-old female black European Short-Hair cat, living outdoors in a suburban environment in Italy, was referred for evaluation of a nodular, vascularized mass of 2 weeks duration. The mass involved the dorsal bulbar conjunctiva at the temporal canthus of OS and invaded the sclera and cornea. Routine ophthalmic and systemic examination, serologic testing, cytology and histology of the mass were performed. Mycobacterium specific polymerase chain reaction (PCR) of variable regions 1, 2 and 3 of the 16S ribosomal RNA (rRNA) gene was also performed.
Results Neutrophils, lymphocytes, macrophages and giant cells with intracytoplasmic acid-fast bacilli were seen on cytological examination. The histological examination confirmed the presence of a granulomatous lesion with acid-fast bacilli within macrophages. Bacteriological culture of the material from the lesion was negative for Mycobacterium spp. Mycobacterium 16S rRNA gene specific PCR was positive.
A diagnosis of feline leprosy was made. The owners refused any treatment, and 1 year later the lesion was still present.
Conclusions Veterinary ophthalmologists should be aware of conjunctivo-corneal leproma as an unusual symptom of leprosy. 相似文献
670.
Mannina L Dugo G Salvo F Cicero L Ansanelli G Calcagni C Segre A 《Journal of agricultural and food chemistry》2003,51(1):120-127
The aim of this research is to find if there is direct evidence relating the fatty acid composition of olive oils to specific cultivars grown within a well-limited geographical region. To group olive oils according to their own cultivars,(13)C high-field nuclear magnetic resonance (NMR) and gas chromatography (GC) were used to analyze 60 extra virgin olive oils from the same Italian region (southwestern Sicily) obtained from four monovarietal cultivars. The (13)C NMR spectrum provides information about glycerol triesters of olive oils, i.e., about the acyl composition of major components and about the fatty acids' positional distribution on the glycerol moiety. GC gives the complete fatty acid profile of olive oil samples. Selection of NMR and GC peaks on the basis of their sensitivity to the different cultivars was performed by using multivariate analysis of variance (MANOVA). Principal component analysis, tree clustering analysis, multidimensional scaling (MDS), and linear discriminant analysis (LDA) were then performed on the MANOVA-selected peaks. Results obtained from (13)C NMR and GC techniques combined with the multivariate statistical procedure are in good agreement and prove the usefulness of fatty acids analysis to group the monovarietal olive oils belonging to the same cultivars. Grouping of olive oils according to their cultivars occurs for particular (13)C resonances all belonging to fatty chains in the sn 1,3 position of the glycerol moiety. 相似文献