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Journal of Plant Research - The current study examined the phylogenetic pattern of medicinal species of the family Apiaceae based on flavonoid groups production, as well as the overall mechanism of...  相似文献   
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A thorough investigation into conditions appropriate for effecting combined eco-friendly bioscouring and/or bleaching of cotton-based fabrics was undertaken. Fabrics used include cotton, grey mercerized cotton, cotton/polyester blend 50/50 and cotton/polyester blend 35/65. The four cotton-based fabric were subjected to bioscouring by single use of alkaline pectinase enzymes or by using binary mixtures of alkaline pectinase and cellulase enzymes under a variety of conditions. Results of bioscouring show that, the bioscoured substrates exhibit fabrics performances which are comparable with these of the conventional alkali scouring. It has been also found that, incorporation of ethylenediaminetetraacetic acid (EDTA) in the bioscouring with mixture from alkaline pectinase and cellulase improves the performance of the bioscoured fabrics. Addition of β-cyclodextrin to the bioscouring solution using alkaline pectinase in admixtures with cellulase acts in favor of technical properties and performance of the bioscoured fabrics. Concurrent bioscouring and bleaching by in situ formed peracetic acid using tetraacetylethylenediamine (TAED) and H2O2 was also investigated. The results reveal unequivocally that the environmentally sound technology brought about by current development is by far the best. The new development involves a single-stage process for full purification/preparation of cotton textiles. The new development at its optimal comprises treatment of the fabric with an aqueous formulation consisting of alkaline pectinase enzyme (2 g/L), TAED (15 g/L), H2O2 (5 g/L), nonionic wetting agent (0.5 g/L) and sodium silicate (2 g/L). The treatment is carried out at 60 °C for 60 min. Beside the advantages of the new development with respect to major technical fabric properties, it is eco-friendly and reproducible. This advocates the new development for mill trials.  相似文献   
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To model catchment surface water quantity and quality, different model types are available. They vary from detailed physically based models to simplified conceptual and empirical models. The most appropriate model type for a certain application depends on the project objectives and the data availability. The detailed models are very useful for short-term simulations of representative events. They cannot be used for long-term statistical information or as a management tool. For those purposes, more simplified (conceptual or meta-) models must be used. In this study, nitrogen dynamics are modeled in a river in Flanders. Nitrogen sources from agricultural leaching and domestic point sources are considered. Based on this input, concentrations of ammonium (NH4-N) and nitrate (NO3-N) in the river water are modeled in MIKE 11 by taking into consideration advection and dispersion and the most important biological and chemical processes. Model calibration was done on the basis of available measured water quality data. To this detailed model, a more simplified model was calibrated with the objective to more easily yield long-term simulation results that can be used in a statistical analysis. The results show that the conceptual simplified model is 1800 times faster than the MIKE 11 model. Moreover the two models have almost the same accuracy. The detailed models are recommended for short-term simulations unless there are enough data for model input and model parameters. The conceptual simplified model is recommended for long-term simulations.  相似文献   
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Molecular markers including inter simple sequence repeats (ISSR) and 18S rDNA gene sequence markers were combined with a detailed morphological analysis to seek characters that discriminate four taxa of Portulaca oleracea s.l. These taxa were identified as the microspecies Portulaca nitida, Portulaca oleracea, Portulaca rausii and Portulaca granulatostellulata. Morphological characters did not provide a clear distinction among the four taxa of P. oleracea s.l. It was found that mixed populations of the taxa occur in several locations and morphological similarities between the microspecies were detected. ISSR analysis indicates that gene flow among populations of different taxa was high and most of the genetic variation (61.9%) occurs within population. These results are inconsistent with the general characteristics of P. oleracea as a self- or 5% cross-pollinated species. A close relationship between P. oleracea, P. rausii and P. granulatostellulata was supported by ISSR and 18S rDNA gene sequence. The ISSR and 18s data support the specific status of P. nitida as a recently evolved taxon. We conclude that P. oleracea exists as a polymorphic species and is not divisible into microspecies based on seed surface as the primary morphological trait, and inter simple sequence repeats (ISSR) and 18S rDNA gene sequence markers. We suggest that the taxa do not merit specific rank as morphological characters and absence of a breeding barrier fail to separate the different populations when they become sympatric.  相似文献   
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Background

The superiority of a single stage combined anterior (first) posterior (second) approach and end-to-side side-to-side grafting neurorrhaphy in direct cord implantation was investigated as to providing adequate exposure to both the cervical cord and the brachial plexus, as to causing less tissue damage and as to being more extensible than current surgical approaches.

Methods

The front and back of the neck, the front and back of the chest up to the midline and the whole affected upper limb were sterilized while the patient was in the lateral position; the patient was next turned into the supine position, the plexus explored anteriorly and the grafts were placed; the patient was then turned again into the lateral position, and a posterior cervical laminectomy was done. The grafts were retrieved posteriorly and side grafted to the anterior cord. Using this approach, 5 patients suffering from complete traumatic brachial plexus palsy, 4 adults and 1 obstetric case were operated upon and followed up for 2 years. 2 were C5,6 ruptures and C7,8T1 avulsions. 3 were C5,6,7,8T1 avulsions. C5,6 ruptures were grafted and all avulsions were cord implanted.

Results

Surgery in complete avulsions led to Grade 4 improvement in shoulder abduction/flexion and elbow flexion. Cocontractions occurred between the lateral deltoid and biceps on active shoulder abduction. No cocontractions occurred after surgery in C5,6 ruptures and C7,8T1 avulsions, muscle power improvement extended into the forearm and hand; pain disappeared.

Limitations include

spontaneous recovery despite MRI appearance of avulsions, fallacies in determining intraoperative avulsions (wrong diagnosis, wrong level); small sample size; no controls rule out superiority of this technique versus other direct cord reimplantation techniques or other neurotization procedures; intra- and interobserver variability in testing muscle power and cocontractions.

Conclusion

Through providing proper exposure to the brachial plexus and to the cervical cord, the single stage combined anterior (first) and posterior (second) approach might stimulate brachial plexus surgeons to go more for direct cord implantation. In this study, it allowed for placing side grafts along an extensive donor recipient area by end-to-side, side-to-side grafting neurorrhaphy and thus improved results.

Level of evidence

Level IV, prospective case series.  相似文献   
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A series of 5-(1H-indol-3-yl)-N-aryl-1,3,4-oxadiazol-2-amines 8a–j has been designed, synthesized and tested in vitro as potential pro-apoptotic Bcl-2-inhibitory anticancer agents based on our previous lead compound 8a. Synthesis of the target compounds was readily accomplished through a cyclisation reaction between indole-3-carboxylic acid hydrazide (5) and substituted isothiocyanates 6a–j, followed by oxidative cyclodesulfurization of the corresponding thiosemicarbazide 7a–j using 1,3-dibromo-5,5-dimethylhydantoin. Active compounds of the series 8a–j were found to have sub-micromolar IC50 values selectively in Bcl-2 expressing human cancer cell lines; notably the 2-nitrophenyl analogue 8a was found to exhibit potent activity, and compounds 8a and 8e possessed comparable Bcl-2 binding affinity (ELISA assay) to the established natural product-based Bcl-2 inhibitor, gossypol. Molecular modeling studies helped to further rationalise anti-apoptotic Bcl-2 binding, and identified compounds 8a and 8e as candidates for further development as Bcl-2 inhibitory anticancer agents.  相似文献   
9.
A series of substituted 3-(benzylthio)-5-(1H-indol-3-yl)-4H-1,2,4-triazol-4-amines has been synthesised and tested in vitro as potential pro-apoptotic Bcl-2-inhibitory anticancer agents. Synthesis of the target compounds was readily accomplished in good yields through a cyclisation reaction between indole-3-carboxylic acid hydrazide and carbon disulfide under basic conditions, followed by S-benzylation. Active compounds, such as the nitrobenzyl analogue 6c, were found to exhibit sub-micromolar IC50 values in Bcl-2 expressing human cancer cell lines. Molecular modelling and ELISA studies further implicated anti-apoptotic Bcl-2 as a candidate molecular target underpinning anticancer activity.  相似文献   
10.
Four different types of cotton-based fabrics, namely, loom-state cotton, cotton/polyester (50/50), cotton/polyester (35/65) and grey mercerized fabrics were bioscoured and bleached. The four substrates are given enzymatic treatment using cellulase enzyme to affect bio-polishing followed by crosslinking using N,N-dimethylol 4,5-dihydroxyethylene urea (DMDHEU) to affect easy care finishing. In another series of experiments the said bioscoured–bleached substrates were similarly crosslinked followed by bio-polishing. Technical properties of the treated fabric that were monitored include: nitrogen content, loss in fabric weight, tensile strength, elongation at break, tear strength, whiteness index, surface roughness and wrinkle recovery angle. Scanning electron micrograph was also examined. Conclusions arrived at from these studies indicated that: post-crosslinking and pre-crosslinking revealed marginal differences in N%, wrinkle recovery angle and whiteness index, a point which validates the argument that cellulase enzyme could not break down the DMDHEU crosslinks within the molecular structure of cotton-containing fabrics. Meanwhile the surface roughness obtained with pre-crosslinking is a bit higher than those of post-crosslinking. Moreover, post-crosslinking caused higher losses in strength properties than pre-crosslinking. Scanning electron micrograph shows that cotton sample pre-crosslinked is almost smooth than those post-crosslinked.  相似文献   
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