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81.
82.
2-Mercaptobenzothiazole, which is mainly used in the rubber industry as a vulcanization accelerator, is very toxic and is considered to be recalcitrant. We show here for the first time that it can be biotransformed and partially mineralized by a pure-culture bacterial strain of Rhodococcus rhodochrous. Three metabolites, among four detected, were identified.  相似文献   
83.
Protected forest areas of Sulawesi are gradually being replaced by intensively used agroforestry systems and farmland, especially in lowland and sub-montane regions. Studies on the impact of these man-induced changes on biodiversity are of urgent conservation concern. We compared the fruit-feeding butterfly assemblage of a natural hill forest to that of a disturbed hill forest, representing a mosaic of old secondary forest and recently abandoned or active subsistence farms. Overall, species richness seemed highest in the disturbed site, but both abundance and diversity of endemic butterflies were significantly higher in the natural forest. Although the butterfly assemblage showed a clear vertical structure in the natural forest, vertical stratification was no longer pronounced at the disturbed site. Comparative studies based on diversity estimates from ground samples should consider not only the scale at which sampling is carried out and influences from nearby habitat patches in the surrounding landscape mosaic, but also possible behavioural changes in stratified species after forest modification. This study shows that higher overall species richness does not imply higher species distinctiveness, and indicates that the contribution of land-use systems to global biodiversity should be evaluated with caution, even when relatively high species richness estimates are found.  相似文献   
84.
Summary The molecular defect has been elucidated in the alpha-1-antitrypsin (PI) gene of a patient with a serum level of only 5 mg/100 ml and a PI M-like phenotype, designated PI MHeerlen. The restriction fragment patterns obtained by probes covering the whole gene and flanking sequences were normal, suggesting no major rearrangements. The nucleotide sequence of the exons, intron/exon junctions, and a part of the promoter region is similar to that of a PI M1(Ala213) gene except for an CT mutation in codon 369, causing a ProLeu substitution. Haplotype analysis and oligonucleotide hybridization studies demonstrated the homozygous state of the mutation in the index case. It is most likely that the Pro369Leu substitution is responsible for the low serum alpha-1-antitrypsin concentration of the patient because this mutation is solely confined to the PI MHeerlen allele and no other relevant mutations could be revealed. As proline is important for the secondary and tertiary structure of proteins, the mutation may cause an abnormal processing of the nascent polypeptide. The same mutation was observed in two unrelated subjects known to carry a PI allele giving a low serum alpha-1-antitrypsin level.  相似文献   
85.
The yeast cell wall consists of an internal skeletal layer and an outside protein layer. The synthesis of both β-1,3-glucan and chitin, which together form the cell wall skeleton, is cell cycle-regulated. We show here that the expression of five cell wall protein-encoding genes (CWP1, CWP2, SED1, TIP1 and TIR1) is also cell cycle-regulated. TIP1 is expressed in G1 phase, CWP1, CWP2 and TIR1 are expressed in S/G2 phase, and SED1 in M phase. The data suggest that these proteins fulfil distinct functions in the cell wall.  相似文献   
86.
Internet-delivered cognitive behavior therapy (ICBT) has been tested in many research trials, but to a lesser extent directly compared to face-to-face delivered cognitive behavior therapy (CBT). We conducted a systematic review and meta-analysis of trials in which guided ICBT was directly compared to face-to-face CBT. Studies on psychiatric and somatic conditions were included. Systematic searches resulted in 13 studies (total N=1053) that met all criteria and were included in the review. There were three studies on social anxiety disorder, three on panic disorder, two on depressive symptoms, two on body dissatisfaction, one on tinnitus, one on male sexual dysfunction, and one on spider phobia. Face-to-face CBT was either in the individual format (n=6) or in the group format (n=7). We also assessed quality and risk of bias. Results showed a pooled effect size (Hedges'' g) at post-treatment of −0.01 (95% CI: −0.13 to 0.12), indicating that guided ICBT and face-to-face treatment produce equivalent overall effects. Study quality did not affect outcomes. While the overall results indicate equivalence, there are still few studies for each psychiatric and somatic condition and many conditions for which guided ICBT has not been compared to face-to-face treatment. Thus, more research is needed to establish equivalence of the two treatment formats.  相似文献   
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An accurate spatial relationship between 3D in-vivo carotid plaque and lumen imaging and histological cross sections is required to study the relationship between biomechanical parameters and atherosclerotic plaque components. We present and evaluate a fully three-dimensional approach for this registration problem, which accounts for deformations that occur during the processing of the specimens. By using additional imaging steps during tissue processing and semi-automated non-linear registration techniques, a 3D-reconstruction of the histology is obtained.The methodology was evaluated on five specimens obtained from patients, operated for severe atherosclerosis in the carotid bifurcation. In more than 80% of the histology slices, the quality of the semi-automated registration with computed tomography angiography (CTA) was equal to or better than the manual registration. The inter-observer variability was between one and two in-vivo CT voxels and was equal to the manual inter-observer variability. Our technique showed that the angles between the normals of the registered histology slices and the in-vivo CTA scan direction ranged 6–56°, indicating that proper 3D-registration is crucial for establishing a correct spatial relation with in-vivo imaging modalities. This new 3D-reconstruction technique of atherosclerotic plaque tissue opens new avenues in the field of biomechanics as well as in the field of image processing, where it can be used for validation purposes of segmentation algorithms.  相似文献   
89.
Biomechanics and Modeling in Mechanobiology - Ascending thoracic aortic aneurysms (ATAAs) are a silent disease, ultimately leading to dissection or rupture of the arterial wall. There is a growing...  相似文献   
90.
Surface plasmon resonance imaging (SPRi) is most frequently used for the label-free measurement of biomolecular interactions. Here we explore the potential of SPRi to measure antibody production of individual hybridoma cells. As a model system, cells from a hybridoma, producing monoclonal antibodies recognizing epithelial cell adhesion molecule (EpCAM), were used. Recombinant human EpCAM protein was immobilized on an SPR sensor and hybridoma cells were introduced into an IBIS MX96 SPR imager and the SPRi response was followed for 10 h. SPRi responses were detected on the spots of the sensor only where ligands of the produced antibody were present. By measuring the SPRi signals on individual cells the antibody production of the individual cells was measured and production rates were calculated. For 53 single EpCAM hybridoma cells the production ranged from 0.16 to 11.95 pg (mean 2.96 pg per cell, SD 2.51) over a period of 10 h. Antibody excretion per cell per hour ranged from 0.02 to 1.19 pg (mean 0.30, SD 0.25). Here we demonstrate for the first time that antibody production of individual cells can be measured and quantified by SPRi, opening a new avenue for measuring excretion products of individual cells.  相似文献   
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