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141.
Uses and Conservation of Plant Species in a National Park—A Case Study of Ben En, Vietnam. This paper surveys the use of wild and cultivated plants by local people in Ben En National Park, Vietnam, and analyzes its impact on the conservation status of some of the utilized species. A total of 208 species used for a range of nonmedicinal purposes are listed. See Hoang et al. (2008a) for 230 medicinal plants used in the park. Most species are used for food. The use of plants contributes very significantly to the livelihood of local people in the park, but the current use patterns are not sustainable and would lead to local extinction of rare and endangered species if no additional conservation measures are introduced. Men collect nonmedicinal plants more often than women. A total of 38 useful plant species are commercialized, and contribute 12% of the average income of individual households. Bamboo shoots of Schizostachyum funghomii (Poaceae) are the most important for income generation. The monetary equivalent of noncommercialized useful plants probably far exceeds the value of the traded plant products. Plant use is independent of the ethnicity of the different populations living in the park. Larger households make use of a greater variety of useful plant species than small families. Abundant species in the forest have a higher use index (UI) than less common species. Out of the 208 useful species, as many as 27 were found to be endangered locally, many more than the 11 or 8 endangered species included in national or global red lists. Currently, useful plants, especially important timber trees, are more abundant in the less disturbed parts of the park, far away from the villages, indicating the pressures of illegal logging and harvesting near villages on the ecosystems.  相似文献   
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Neutrophils of patients with Beh?et's syndrome generate increased amounts of oxygen free radicals. This phenomenon is inhibited by superoxide dismutase (SOD) and catalase and is implicated in vasculitis. We treated seven patients with active Beh?et's syndrome by CuZn SOD intramuscularis with dramatic improvement of clinical symptoms.  相似文献   
144.
Multiple HindIII-restriction fragments of Salmonella typhimurium and Salmonella typhi chromosomal DNA exhibited homology with the heat-labile enterotoxin (LT1) gene of Escherichia coli as determined by Southern blot analysis. A 9.4 kb HindIII restriction fragment identified in S. typhimurium and S. typhi chromosomal DNA reacted with both eltA and eltB gene probes. However, the homology of the 9.4 kb DNA fragment from these Salmonella species was greater with eltB than eltA. In addition, a synthetic oligonucleotide probe, made to a portion of the putative GM1-ganglioside binding region of cholera toxin (CT) and LT1, hybridized with the 9.4 kb DNA fragment of S. typhimurium but not with the 9.4 kb fragment found in S. typhi isolates. The hybridization of multiple restriction fragments of Salmonella DNA with eltA and eltB gene sequences further suggests duplication of the stx operon on the chromosome of these bacteria.  相似文献   
145.
Epigenetic factors have recently emerged as key regulators of the defense response to pathogens in plants. The epigenetic mechanisms underlying defense regulation have been investigated mostly in Arabidopsis, while our understanding of the epigenetic regulation of defense in rice is limited. In this review, we summarize recent findings surrounding epigenetic mechanisms for defense in rice, primarily focusing on DNA methylation, histone modification, and small RNA regulation. In particular, we focused on RNA-directed DNA methylation (RdDM) and other epigenetic regulatory mechanisms that are involved in disease resistance. Finally, we explored potential epigenetic factors that might regulate the defense response in rice by analyzing available microarray data that can be used to uncover details of epigenetics regulation.  相似文献   
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Process intensification of monoclonal antibody production is leading to more concentrated feed media causing issues with precipitation of solids from the media solution. This results in processing problems since components in the precipitate are no longer in solution, changing the media composition and leading to variability in cell culture performance. The goal of this work is to characterize the feed media precipitate, and in particular to identify the precipitated components so that mitigation strategies can be developed. From the conducted analysis, the precipitate was predominately found to be organic and was analyzed with liquid chromatography-mass spectrometry and inductively coupled plasma-optical emission spectroscopy (ICP-OES) to identify the constituent components. Up to ten amino acids were identified with tyrosine (approximately 77 wt.%) and phenylalanine (approximately 4 wt.%) being the most prevalent amino acids. Elemental analysis with ICP-OES revealed that inorganic components were accounted for less than one weight percentage of the solid precipitate with metal sulfates being the predominant inorganic components.  相似文献   
149.

Background

Between 2003 and 2005, highly pathogenic avian influenza A (H5N1) viruses caused large scale outbreaks in poultry in the Ho Chi Minh City area in Vietnam. We studied the prevalence of antibodies against H5N1 in poultry workers and cullers who were active in the program in Ho Chi Minh City in 2004 and 2005.

Methodology/Principal Findings

Single sera from 500 poultry workers and poultry cullers exposed to infected birds were tested for antibodies to avian influenza H5N1, using microneutralization assays and hemagglutination inhibition assay with horse blood. All sera tested negative using microneutralization tests. Three samples showed a 1∶80 titer in the hemagglutination inhibition assay.

Conclusions/Significance

This study provides additional support for the low transmissibility of clade 1 H5N1 to humans, but limited transmission to highly exposed persons cannot be excluded given the presence of low antibody titers in some individuals.  相似文献   
150.
Many of the edible wild plants that are included in local food baskets have both therapeutic and dietary functions. Such medicinal foods have been part of Eastern medicinal theories since ancient times and have recently received attention in the USA and Europe within the fields of functional foods, neutraceuticals and phyto-nutrients. This paper provides an example from Vietnam of the continued use of a multitude of edible wild vegetables. Vietnamese traditional medicine also holds an important position within the health care system and many of the plants that are used have both dietary and medicinal functions. Using a combination of qualitative and quantitative techniques (Rapid Rural Appraisal and Food Frequency Questionnaires), information on over 90 species of edible wild plants was obtained from 4 villages in the Mekong Delta and the Central Highlands. About a third of the plants also had therapeutic roles, forty percent were used also as livestock feeds and one fifth were used as food/livestock feed/ medicine. From a nutrition viewpoint it is important to pay attention to this group of traditional foods for several reasons. Their direct nutritional contribution is often significant but neglected. Very little is known about the health benefits of regular consumption of small quantities of medicinal foods and an important “medicinal role” of traditional plant medicines may be the contribution of small quantities of trace minerals and vitamins. The parallel functions as livestock feeds make animal products more accessible to poor households and help improve the quality of their diets.  相似文献   
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