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1.
Iron deficiency and anemia affect a substantial portion of the world's population, provoking severe health problems to the people suffering these conditions, as well as important economic losses to the regions in which this nutritional deficiency is significant. In this work, the principal causes and consequences produced by this deficiency are discussed, as well as the different strategies that can be applied in order to prevent and solve this nutritional problem.  相似文献   

2.
Iron deficiency     
Iron deficiency and anemia affect a substantial portion of the world’s population, provoking severe health problems to the people suffering these conditions, as well as important economic losses to the regions in which this nutritional deficiency is significant. In this work, the principal causes and consequences produced by this deficiency are discussed, as well as the different strategies that can be applied in order to prevent and solve this nutritional problem.  相似文献   

3.
Metabolic aspects of organogenesis in the shoot apical meristem   总被引:1,自引:0,他引:1  
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4.
In this article, we first document the virtually complete absence of infectious disease examples and concerns at the time bioethics emerged as a field. We then argue that this oversight was not benign by considering two central issues in the field, informed consent and distributive justice, and showing how they might have been framed differently had infectiousness been at the forefront of concern. The solution to this omission might be to apply standard approaches in liberal bioethics, such as autonomy and the harm principle, to infectious examples. We argue that this is insufficient, however. Taking infectious disease into account requires understanding the patient as victim and as vector. Infectiousness reminds us that as autonomous agents we are both embodied and vulnerable in our relationships with others. We conclude by applying this reunderstanding of agency to the examples of informed consent and distributive justice in health care.  相似文献   

5.
Recent advances in technology and associated methodology have made the current period one of the most exciting in molecular biology and medicine. Underlying these is an appreciation that modern research is driven by increasing large amounts of data being interpreted by interdisciplinary collaborative teams which are often geographically dispersed. The availability of cheap computing power, high speed informatics networks and high quality analysis software has been essential to this as has the application of modern quality assurance methodologies. In this review, we discuss the application of modern 'High-Throughput' molecular biological technologies such as 'Microarrays' and 'Next Generation Sequencing' to scientific and biomedical research as we have observed. Furthermore in this review, we also offer some guidance that enables the reader as to understand certain features of these as well as new strategies and help them to apply these i-Gene tools in their endeavours successfully. Collectively, we term this 'i-Gene Analysis'. We also offer predictions as to the developments that are anticipated in the near and more distant future.  相似文献   

6.
New investigations on Otto Hauser's skeleton findings and the excavations of this Swiss citizen in Southwest France from 1906 until 1914 placed the activities of this archaeologist again in the focus of scientific and public interest. This paper describes life and oeuvre of Otto Hauser and discusses the importance of the skeletons found by him and Hermann Klaatsch as well as the consequences of their discovery. The efforts of Otto Hauser to publish his discoveries, to present and spread his view concerning the evolution of man were remarkably manifold as well as the parallels between ancient man and contemporary ethnic groups living on a low technological level drawn by him and to wake and to promote the interest in prehistory. Many books, brochures, articles and public lectures contributed to this intention as well as co-operation with local historians and scientists of other disciplines, and also many films, teaching and illustrative materials. The scientific collection of the authors of this article comprises more than 6,500 written documents and photos.  相似文献   

7.
8.
Food fortification has been shown to be an effective strategy to overcome iron malnutrition. When a new iron compound is developed for this purpose, it must be evaluated from a nutritional and technological point of view before adding it into foods. In this way, we have evaluated ferrous gluconate stabilized by glycine as a new iron source to be used in wheat flour fortification. We performed biological studies in rats as well as sensory perceptions by human subjects in wheat flour fortified with this iron source. The productions of pentane as a rancidity indicator as well as the change of the sensorial properties of the biscuits made with stabilized ferrous gluconate-fortified wheat flour were negligible. Iron absorption in water from this iron source was similar to the reference standard ferrous sulfate. Nevertheless, because of the phytic acid content, iron absorption from fortified wheat flour decrease 40% for both iron sources. The addition of zinc from different sources did not modify iron absorption from ferrous sulfate and stabilized ferrous gluconate in water and wheat flour. The iron absorption mechanism as well as the biodistribution studies demonstrate that the biological behavior of this iron source does not differ significantly from the reference standard. These results demonstrate that the iron source under study has adequate properties to be used in wheat flour fortification. Nevertheless, more research is needed before considering this iron source for its massive use in food fortification.  相似文献   

9.
The zebrafish (Danio rerio) embryo has emerged as an important model of vertebrate development. As such, this model system is finding utility in the investigation of toxic agents that inhibit, or otherwise interfere with, developmental processes (i.e. developmental toxins), including compounds that have potential relevance to both human and environmental health, as well as biomedicine. Recently, this system has been applied increasingly to the study of microbial toxins, and more specifically, as an aquatic animal model, has been employed to investigate toxins from marine and freshwater microalgae, including those classified among the so-called "harmful algal blooms" (HABs). We have developed this system for identification and characterization of toxins from cyanobacteria (i.e. "blue-green algae") isolated from the Florida Everglades and other freshwater sources in South and Central Florida. Here we review the use of this system as it has been applied generally to the investigation of toxins from marine and freshwater microalgae, and illustrate this utility as we have applied it to the detection, bioassay-guided fractionation and subsequent characterization of developmental toxins from freshwater cyanobacteria.  相似文献   

10.
棘腹蛙(Quasipaaboulengeri)是无尾目(Anura)叉舌蛙科(Dicroglossidae)棘胸蛙属的两栖动物。因其以农业和森林害虫为食且对生存环境要求高的特点,故有保护和监测环境的生态功能。但由于生态环境恶化和过度捕捉等原因,造成野生棘腹蛙数量急剧下降,被《中国脊椎动物红色名录》列为易危种。本文从棘腹蛙的习性、生存环境特征、系统进化、人工养殖和资源保护等方面进行了综述,为进一步研究棘腹蛙提供基础资料和理论依据。  相似文献   

11.
King SM  Burdette JE 《BMB reports》2011,44(7):435-445
Serous ovarian cancer is one of the most lethal gynecological malignancies. Progress on effective diagnostics and therapeutics for this disease are hampered by ambiguity as to the cellular origins of this histotype of ovarian cancer, as well as limited suitable animal models to analyze early stages of disease. In this report, we will review current animal models with respect to the two proposed progenitor cells for serous ovarian cancer, the ovarian surface epithelium and the fallopian tube epithelium.  相似文献   

12.
In this work, we performed for the first time a proteomic approach to the processes induced by long-term potassium starvation in the halotolerant yeast Debaryomyces hansenii. The proteomic profile under this ionic stress conditions shows that important changes in gene expression take place as an adaptive response. We found a significant protein expression repression as well as metabolic changes such as the inhibition of the upper part of the glycolysis, the amino acid synthesis, and the Krebs cycle. On the other hand, genes related to stress responses, protein degradation, and sterols synthesis were upregulated in response to potassium deprivation. The findings in this study provide important information about how this particular yeast copes with ionic stress at molecular levels, which might further enrich the global understanding of salt tolerance processes in eukaryal systems and moreover highlighting the importance of the 'omics' approaches as a complement to the classical physiological studies.  相似文献   

13.
A new approach to enzymatic peptide synthesis by using aminoacyl-tRNA synthetase (ARS) as a catalyst has been investigated. Four ARSs (AspRS, HisRS, LeuRS and TyrRS) have been purified from a thermophilic bacterium, Bacillus stearothermophilus. By using TyrRS as a catalyst, tyrosine and leucinamide were shown to be condensed in the presence of ATP to give tyrosylleucinamide. In this manner, all of the ARSs investigated catalyzed the peptide synthesis reactions. TyrRS did not have strict specificity for the amino acid derivatives used as substrates and even D-amino acids were incorporated into peptides fairly easily in this enzymatic reaction. Preparative scale synthesis of L-Tyr-L-LeuNH2 was carried out and from this the scope and limitation of this new enzymatic reaction as a tool to the peptide synthesis has been described.  相似文献   

14.
The gene encoding of an alcohol dehydrogenase C (ADHC) from Mycobacterium smegmatis was cloned and sequenced. The protein encoded by this gene has 78% identity with Mycobacterium tuberculosis and Mycobacterium bovis BCG ADHC. The M. smegmatis ADHC was purified from M. smegmatis and the kinetic parameters of this enzyme showed that using NADPH as electron donor it has a strong preference for aliphatic and aromatic aldehyde substrates. Like the M. bovis BCG ADHC, this enzyme is more likely to act as an aldehyde reductase than as an alcohol dehydrogenase. The discovery of such an ADHC in a fast-growing, and easily engineered mycobacterial species opens the way to the utilisation of this M. smegmatis enzyme as a convenient model for the study of the physiological role of this alcohol dehydrogenase in mycobacteria.  相似文献   

15.
In this paper we outline the rationale for applying British Standard BS5750 to a medical equipment management service and introduce some of the concepts of the standard as they apply to this field. We see this application as essential in today's legal and commercial environment and indicate the ways in which this work is being carried forward by the Medical Equipment Management Organisation into total quality management systems.  相似文献   

16.
Olive stone an attractive source of bioactive and valuable compounds   总被引:1,自引:0,他引:1  
The olive stone and seed are an important byproduct generated in the olive oil extraction and pitted table olive industries. As a lignocellulosic material, the hemicellulose, cellulose and lignin are the main components of olive stone as wells as protein, fat, phenols, free sugars and poliols composition. The main use of this biomass is as combustion to produce electric energy or heat. Other uses such as activated carbon, furfural production, plastic filled, abrasive and cosmetic or other potential uses such as biosorbent, animal feed or resin formation have been cited. In this article, an overview of the characterization and main uses of olive stone and seed are described for the first time. Also, this review discusses the potential use of this material based on each component. In this way, a new approach to the olive stone and seed by pretreating with a steam explosion followed by chemical fractionation is described.  相似文献   

17.
Since a genome is a discrete sequence, the elements of which belong to a set of four letters, the question as to whether or not there is an error-correcting code underlying DNA sequences is unavoidable. The most common approach to answering this question is to propose a methodology to verify the existence of such a code. However, none of the methodologies proposed so far, although quite clever, has achieved that goal. In a recent work, we showed that DNA sequences can be identified as codewords in a class of cyclic error-correcting codes known as Hamming codes. In this paper, we show that a complete intron-exon gene, and even a plasmid genome, can be identified as a Hamming code codeword as well. Although this does not constitute a definitive proof that there is an error-correcting code underlying DNA sequences, it is the first evidence in this direction.  相似文献   

18.
Some strains of Bacillus sphaericus are entomopathogenic to mosquito larvae, which transmit diseases, such as filariasis and malaria, affecting millions of people worldwide. This species is unable to use hexoses and pentoses as unique carbon sources, which was proposed to be due to the lack of glycolytic enzymes, such as 6-phosphofructokinase (PFK). In this study, PFK activity was detected and the pfk gene was cloned and sequenced. Furthermore, this gene was shown to be present in strains belonging to all the homology groups of this heterogeneous species, in which PFK activity was also detected. A careful sequence analysis revealed the conservation of different catalytic and regulatory residues, as well as the enzyme's phylogenetic affiliation with the family of allosteric ATP-PFK enzymes.  相似文献   

19.
Sexual dimorphism of recombination has been held by classic genetic theory to disfavor the heterogametic sex. Assessment of chiasma frequencies at the diplotene stage of meiosis has been used as a valid measure of this concept and in many species has revealed, as expected, an increased frequency in female vs. male germ cells. Mesocricetus brandti, a species currently used in investigations of gonadal regression, photoperiods, and hibernation, was found by this measure to be an exception to this rule, with an average of 29.81 chiasmata in spermatocytes and 23.16 in oocytes. Sites of crossing-over unique to each sex were also detected. Oogenesis occurs in this species as a postnatal phenomenon and is suggested as a possible critical factor for the exceptional recombinant behavior.  相似文献   

20.
With the increasing number of cases of latent and drug resistant tuberculosis, there is an urgent need to develop new, potent molecules capable of combating this deadly disease. Molecules containing oxadiazoles are one such class that could be considered to fulfil this need. Oxadiazole regioisomers have been explored in drug discovery programs for their ability to act as effective linkers and also as pharmacophoric features. Oxadiazoles can act as bioisosteric replacements for the hydrazide moiety which can be found in first line anti-TB drugs, and some have been also reported to interact with newer anti-TB targets. In this context, the present review describes the potential of oxadiazoles as antituberculosis agents.  相似文献   

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