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211.
ABSTRACT

Sixteen species of Gymnosperms have been screened for cytosolic ascorbate peroxidase by means of native polyacrylamide gel electrophoresis. This analysis shows that a single form of the enzyme is the most common situation. The enzyme reveals a similar electrophoretic mobility in species belonging to the same genus and sometimes to different genera. In some Pinaceae, two bands of activity were observed. The presence in the archaic spermatophyte Ginkgo biloba, as well as in the more advanced monocotyledons, of three isoforms of ascorbate peroxidase, might suggest that three different cytosolic ascorbate peroxidase genes were already present in this archaic species.  相似文献   
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We report the presence of auto-anti-Id antibodies in the glomerular immune deposits of a rabbit with chronic serum sickness induced by daily i.v. injections of bovine serum albumin. Auto-anti-Id antibodies were also documented in the serum of the same animal during the phase of chronic serum sickness in which immune complex glomerulonephritis develops. These results suggest that auto-anti-Id may normally participate in pathologic reactions and may be one of the mechanisms of potentiation and/or progression of immunopathologic lesions.  相似文献   
217.
Vertebrate and many invertebrate globin genes have a three-exon/two-intron organization, with introns in highly conserved positions. According to the ``intron early' hypothesis, introns are the vestigial segments which flank previously independent coding sequences, thus providing evidence for the assembly of the ancient proteins by ``exon shuffling.' In this paper, we report the analysis of the genes of the bivalve mollusk Scapharca inaequivalvis tetrameric hemoglobin (HbII), which support this hypothesis, at least for the hemoglobin genes. We show the existence of ``minigenes' in the IIA and IIB globin genes, spanning part of the first and second introns, ``in frame' with the heme-binding domain coded by the second exon. Further support for the exon shuffling hypothesis can be found in the degree of identity of the ``new' translated sequences with those flanking the central protein domain of some invertebrate hemoglobins. Received: 31 July 1997 / Accepted: 12 December 1997  相似文献   
218.
Purpose

This study aims to apply the product environmental footprint (PEF) methodology to a wooden wall element, the Massiv–Holz–Mauer® (MHM), in an existing building in Northern Italy. The PEF is a multi-criteria measure of the environmental performance of products throughout their life cycle (European Commission 2013).

Methods

The environmental footprint of the MHM wall element was calculated for the impact categories required by the PEF, using a cradle-to-grave approach. Foreground data was collected at each life stage and completed using data from the Ecoinvent 3.1 database (Wernet et al. 2016). An additional analysis (optional according to the PEF methodology) was conducted for assessing the sustainability of forest management in the sites where wood is extracted from, using data from the forest management plan.

Results and discussion

The results show that, for most of the environmental indicators, the use phase has the highest environmental impact, followed by the production, end-of-life, raw material acquisition, and construction phases. These results depend on the different duration of the life cycle phases, and on the attribution of the total operational energy of the building to the structural components of the wall, though other factors, such as the efficiency of the heating system, may be responsible. Future PEF sectorial specification should specify how to account for the use phase of structural building components. For the majority of the impact categories, the impact is mainly due to processes that occur in the background system, such as production of capital goods and construction of facilities and storehouses. The wooden material production generates relatively low impacts, thanks to the fact that the wood is sourced locally and from forests where a close-to-nature forest management is adopted, characterized by natural regeneration without the use of fertilizers and pesticides.

Conclusions

This study shows that the PEF methodology can be successfully applied to a single wood supply chain, allowing the identification of the main hotspots and actions for reducing the environmental impacts. The PEF leaves space for additional environmental information, which, for some product categories, may play an important role. In the case of wood products, we suggest the inclusion of an assessment, even qualitative, of the sustainability of forest management.

  相似文献   
219.
For the present study we asked whether the endometrial fluid lipidomic may be a useful approach to predict endometrial receptivity in freeze‐all cycles. For this case‐control study, endometrial fluid samples were collected from 41 patients undergoing freeze‐all cycles. Samples were split depending on the pregnancy outcome: positive group (n = 24) and negative group (n = 17). Data were acquired by the matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS‐DA) were applied. A list of potential biomarker ion ratios was obtained and the values were used to build a receiver operating characteristic (ROC) curve to predict pregnancy success. The lipid categories were attributed by LIPID MAPS database. Ion ratios were established according to their correlations and used for the analysis. The PCA showed a tendency of separation between the studied groups, whereas the PLS‐DA was able to clearly distinguish them. Fifteen ratios (13 hyper‐represented in the negative and two hyper‐represented in the positive group) were selected according to their importance for model prediction. These ratios were used to build the ROC curve, which presented an area under curve of 84.0% (95%CI: 69.2–97.4%; p = 0.009). These findings suggest that lipidomic profiling of endometrial fluid may be a valuable tool for identifying the time interval comprising the window of implantation.  相似文献   
220.
Thalidomide is the best known human teratogen. Although withdrawn from the market in 1961, thalidomide was remarketed after 1965 in several countries, for the treatment of erythema nodosum leprosum. Thalidomide has a potent immunomodulatory property and has now a number of approved and off-label uses in dermatologic, oncologic, infectious and gastrointestinal conditions. In the U.S., FDA approved the use of thalidomide in 1998, but no cases of thalidomide embriophaty were registered after that. Since 1996 no new cases were reported in Latin America. However, the Teratogen Information Service (TIS) Porto Alegre, recorded three new cases of thalidomide embriophaty born in Brazil since 2005. Considering that these three cases were not registered through a systematic surveillance system, but that came to our attention through a series of coincidental random events, it can be assumed that the actual occurrence of affected babies by thalidomide continues being as frequent as denounced ten years ago.  相似文献   
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