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11.
We analysed the mycorrhizal types of two coastal Mediterranean plant communities. Plants belonging to 82 species of 46 families growing in two Mediterranean study sites located within a Regional Natural Park in Italy (Macchia Lucchese) and in a National Park in Croatia (Brijuni) were assessed for the type of their mycorrhizal associations. Mycorrhizas occurred in 83% and 90% of the plant species surveyed in Macchia Lucchese and in Brijuni, respectively. On the basis of macroscopic and microscopic characteristics, six different mycorrhizal types were found, and their co-occurrence in the same plant community showed the large mycorrhizal diversity in Mediterranean vegetation. Different occurrence patterns of mycorrhizal types have been recognised in diverse habitats within Macchia Lucchese, from sand dune plant communities to sclerophyllous woodland. Mycorrhizal type abundance calculated on a floristic basis was very different from that obtained using a vegetation cover index.  相似文献   
12.
Free and glucosidic bound leaf volatiles of Degenia velebitica were isolated and fractionated simultaneously into H2O‐soluble, H2O‐insoluble, and highly volatile compounds by hydrodistillation–adsorption (HDA) and analyzed by GC/MS. Among the 24 constituents identified, the main compounds obtained by the HDA method were S‐ and/or N‐atom containing compounds, i.e., 6‐(methylsulfanyl)hexanenitrile ( 10 ; 26.78%), dimethyl trisulfide ( 6 ; 26.35%), 3,4,5‐trimethylpyrazole ( 17 ; 13.33%), hex‐5‐enenitrile ( 2 ; 10.11%), dimethyl tetrasulfide ( 8 ; 4.93%), and pent‐4‐enyl isothiocyanate ( 7 ; 4.45%). In addition, O‐glycosidically bound volatiles and free volatiles were isolated by solvent extraction. Sixteen volatile O‐aglycones and twelve free volatile components were identified. The main O‐aglycones were eugenol ( 19 ; 24.15%), 2‐methoxy‐4‐vinylphenol ( 11 ; 11.50%), and benzyl alcohol ( 20 ; 9.49%), and the main free volatiles were (9Z,12Z)‐octa‐9,12‐dienic acid (38.35%), hexadecanoic acid (22.64%), and phytol (5.80%). The H2O‐soluble volatile fraction obtained by HDA, containing mostly glucosinolate degradation products and 3,4,5‐trimethylpyrazole ( 17 ), was evaluated for antimicrobial activity by determining inhibition zones with the diffusion method as well as minimal inhibitory concentrations (MIC) and minimal microbicidal concentrations (MMC) with the micro‐dilution method. The fraction expressed activity against the tested Gram‐positive and Gram‐negative bacteria as well as against yeast, with MIC values equal to or lower than 16.7 μg/ml.  相似文献   
13.
Fumagillin is a naturally secreted antibiotic of the fungus Aspergillus fumigatus. It is used in veterinary medicine against microsporidiosis of bees and fish. In this study, the genotoxicity of fumagillin (in the form of fumagillin dicyclohexylamine) was evaluated in mouse bone-marrow cells using the mitotic index (MI), the chromosome aberration (CA) assay, and the micronucleus (MN) test. Fumagillin was administered to BALB/c mice by gavage, at doses of 25, 50, 75 mg/kg body weight (bw), repeated for 7 days at 24-h intervals, with water-sugar syrup as a negative control and cyclophosphamide (40 mg/kg bw) as a positive control. All experimental doses of fumagillin induced a significant decrease (p<0.001) in MI (3.47+/-0.04%, 3.17+/-0.01%, and 2.27+/-0.02%, respectively) in comparison with the negative control (6.00+/-0.01%). Fumagillin significantly (p<0.001) increased the frequency of MN (4.98+/-0.35, 8.45+/-0.57, and 12.02+/-0.37, respectively) over negative control (1.04+/-0.28). Significantly increased frequencies (p<0.01 or p<0.001) of numerical chromosomal aberrations (aneuploidies and polyploidies) and structural chromosomal aberrations such as gaps, breaks, and centric rings were observed at the highest experimental dose of fumagillin (75 mg/kg bw) compared with the negative control. However, with respect to the induction of Robertsonian translocations, both the intermediate (50 mg/kg bw) and highest (75 mg/kg bw) experimental dose caused a significant (p<0.001) increase (7.12+/-0.26 and 9.00+/-0.10, respectively) in comparison with the negative control (0.00+/-0.00). Chromosomes 4 and 19 participated in these Robertsonian translocations. Regarding total cytogenetic changes, a significant increase (p<0.001) was observed in both the intermediate dose group (17.36+/-1.83) and the highest dose group (59.49+/-1.92) compared with the negative control (7.00+/-1.35). These results suggest that fumagillin has genotoxic (clastogenic) potential in mammals in vivo.  相似文献   
14.
Conduction of tele-3D-computer assisted operations as well as other telemedicine procedures often requires highest possible quality of transmitted medical images and video. Unfortunately, those data types are always associated with high telecommunication and storage costs that sometimes prevent more frequent usage of such procedures. We present a novel algorithm for lossless compression of medical images that is extremely helpful in reducing the telecommunication and storage costs. The algorithm models the image properties around the current, unknown pixel and adjusts itself to the local image region. The main contribution of this work is the enhancement of the well known approach of predictor blends through highly adaptive determination of blending context on a pixel-by-pixel basis using classification technique. We show that this approach is well suited for medical image data compression. Results obtained with the proposed compression method on medical images are very encouraging, beating several well known lossless compression methods. The predictor proposed can also be used in other image processing applications such as segmentation and extraction of image regions.  相似文献   
15.
The aim of the research was to show our diagnostic and therapeutic experience with antiphospholipid syndrome (APS) in pregnant women. 36 pregnant women suspect on APS were included in the study: 32 with primary antiphospholipd syndrome (PAPS) and 4 with secondary antiphospholipid syndrome (SAPS). All pregnant women received low-molecular-weight-heparin (LMWH) and low dose aspirin (LDA) therapy. Control group represented 26 women with SAPS and previous bad reproductive anamnesis. Average pregnancy lasted 37.06 +/- 0.707 weeks. LMWH and LDA therapy was successful in 97.22%. Lupus anticoagulant (LA) was found to be more frequent in PAPS group (71.87%). Anticardiolipin antibodies (aCL) were found to be more frequent in SAPS (26.66%). For three patients (3.37%), PAPS was diagnosed due to a fact that they had positive antibeta2-glycoproteinl (antibeta-GP1). To make APS diagnosis, it is of great importance to search for all antiphospholipid antibodies. LMWH and low dose of acetylsalicylic acid should be the first choice therapy.  相似文献   
16.
We estimated neutral diversity of 21 European cattle breeds with 105 microsatellites. Nine of them resembled unselected Balkan Buša strains with diffuse breeding barriers and the 12 others were strongly differentiated, isolated breeds. Because of the impact of neutral genetic diversity on long-term population adaptive capacity, we discuss the long-term outcome of different conservation priorities in a subdivided metapopulation of the investigated cattle breeds. The optimal contribution to a pool of total genetic diversity allocated more than 95% of long-term relevant neutral diversity to virtually unselected strains of the Balkan Buša, while the maximization of total variance preferred inbred breeds. Current artificial selection methods, such as genomic selection sped up and a recovery of underestimated traits becomes quickly impossible. We emphasize that currently neutral and even deleterious alleles might be required for future genotypes in sustainable and efficient livestock breeding and production systems of a 21st century. We provide cumulative evidences that long-term survival relies on genetic complexity and complexity relies on allelic diversity. Our results suggest that virtually unselected, nonuniform strains harbor a crucial proportion of neutral diversity and should be conserved with high global priority. As one example, we suggest a cooperative maintenance of the nondifferentiated, highly fragmented, and fast vanishing metapopulation of Balkan Buša.  相似文献   
17.
In a 62-year-old man with permanent atrial fibrillation and recurrent stroke, a large right atrial thrombus attached to a permanent pacemaker lead was incidentally identified by transesophageal echocardiography. Surgical treatment, recommended because of the large dimensions of the mass, was refused by the patient, and thrombus was successfully dissolved by anticoagulant treatment. Pathogenesis of pacemaker lead thrombosis, clinical implications, diagnostic and therapeutic options are discussed.  相似文献   
18.
The S1 and S2 subsite specificity of recombinant human cathepsins X was studied using fluorescence resonance energy transfer (FRET) peptides with the general sequences Abz-Phe-Xaa-Lys(Dnp)-OH and Abz-Xaa-Arg-Lys(Dnp)-OH, respectively (Abz=ortho-aminobenzoic acid and Dnp=2,4-dinitrophenyl; Xaa=various amino acids). Cathepsin X cleaved all substrates exclusively as a carboxymonopeptidase and exhibited broad specificity. For comparison, these peptides were also assayed with cathepsins B and L. Cathepsin L hydrolyzed the majority of them with similar or higher catalytic efficiency than cathepsin X, acting as an endopeptidase mimicking a carboxymonopeptidase (pseudo-carboxymonopeptidase). In contrast, cathepsin B exhibited poor catalytic efficiency with these substrates, acting as a carboxydipeptidase or an endopeptidase. The S1' subsite of cathepsin X was mapped with the peptide series Abz-Phe-Arg-Xaa-OH and the enzyme preferentially hydrolyzed substrates with hydrophobic residues in the P1' position.  相似文献   
19.
We are presenting a case of isolated fulminant meningococcal sepsis with two and a half year old child. Initial symptoms were obscure and common to many medical conditions, but also previously described as symptoms of meningococcal sepsis. Unrecognizing the seriousness of the condition child died at home, within few hours after examination and discharge from the hospital. Autopsy and microbiological findings unquestionably proved that the child died from septic shock caused by fulminant meningococcal sepsis.  相似文献   
20.
Bovine spinal muscular atrophy (SMA), an autosomal recessive neurodegenerative disease, has been mapped at moderate resolution to the distal part of Chromosome 24. In this article we confirm this location and fine-map the SMA locus to an interval of approximately 0.8 cM at the very distal end of BTA24. Despite remarkable similarity to human SMA, the causative gene SMN can be excluded in bovine SMA. However, the interval where the disease now has been mapped contains BCL2, like SMN an antiapoptotic factor, and shown to bind to SMN. Moreover, knockout mice lacking the BCL2 gene show rapid motor neuron degeneration with early postnatal onset, as observed in bovine SMA. A comparative cattle/human map of the distal end of BTA24, based on the emerging bovine genome sequencing data, shows conserved synteny to HSA18 with hints of a segmental duplication and pericentic inversion just after the last available bovine marker DIK4971. This synteny lets us conclude that SMA is in immediate vicinity of the telomere. Candidate gene analysis of BCL2, however, excludes most of this gene, except its promoter region, and draws attention to the neighboring gene VPS4B, part of the endosomal protein-sorting machinery ESCRT-III which is involved in several neurodegenerative diseases. Stefan Krebs and Ivica Medugorac contributed equally to this work and agreed to be considered as first authors.  相似文献   
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