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521.
Silvestre D Martìnez-Costa C Lagarda MJ Brines J Farré R Clemente G 《Biological trace element research》2001,80(1):1-11
The aim of the study has been to analyze the evolution of copper, iron, and zinc contents in human milk, from colostrum to
the third postpartum month, following a longitudinal design, under specific conditions of sample collection and to apply an
analytical procedure previously optimized to reduce any variation outside physiological lactation.
The copper, iron, and zinc concentrations in 144 milk samples from 39 healthy puerpera women, were analyzed in five stages
by flame atomic absorption spectrometry, following a standardized protocol.
Copper presented a gradual decrease from 0.38 mg/L to 0.19 mg/L by the 90th day; the particular analysis from colostrum to
transitional milk manifested the following two tendencies. Whereas an increase from 0.19 to 0.42 mg/L was observed in some
women, a decrease from 0.53 to 0.45 mg/L was detected in others; therefore, copper presented two significant behaviors in
the evolution from colostrum to transitional milk. In both cases, the evaluated changes were significant. The iron content
varied from 0.56 to 0.40 mg/L by the 30th day, remaining constant until the first trimester concluded. The average zinc concentration
decreased sharply from 7.99 to 3.3 mg/L on d 15; the rate of decrease slowed down gradually until 1.05 mg/L. 相似文献
522.
523.
Francisco Salatiel Clemente de Souza Armando Muniz Calouro 《Primates; journal of primatology》2018,59(5):469-474
The predation of army ants (Eciton rapax) was recorded during an observational study of the feeding behavior of a group of titi monkeys (Plecturocebus toppini) in an urban fragment of forest in Acre, Brazil. During one observed event, the group’s adult female used its tail to retrieve ants, a type of behavior not observed previously in this genus. All incidents of on-forest floor foraging occurred during the dry season, when fruit was least abundant in the forest, while on other occasions, the ants were captured from tree branches and leaves. The observation of predation and ground-level foraging recorded in this study reinforce the adaptive capacity of P. toppini for survival in fragmented forests, and this was also the first record of the predation of army ants by this titi species. 相似文献
524.
Jerônimo B. B. Sansevero Jorge M. Alonso Micael C. Booth Mateus M. Bueno Lucas S. Carvalho Nicoló Clemente Meri Diana S. Foesch Felipe A. Mateus Ricardo Valcarcel 《Restoration Ecology》2018,26(5):997-1004
Several ambitious restoration targets have been set for recovering degraded ecosystems in Brazil (21 million hectares with a legal deficit of native vegetation). The development of scientific knowledge and skilled professionals is necessary to meet this demand and is fundamental for achieving success in medium‐ and long‐term restoration. In this study, we describe the availability and profile of postgraduate courses on ecological restoration in Brazil. We surveyed 272 postgraduate programs, comprising six specific areas of concentration (forestry, soil sciences, botany, environmental engineering, ecology, and environmental science). We analyzed all selected courses in terms of location, approach (economic, social, and legal), and restoration techniques. Only 27% of the postgraduate programs analyzed offer ecological restoration courses, and 49% of these are offered in the southeast region of the country. Regions covered by nonforest ecosystems, such as Pampas, Caatinga, and Pantanal, were poorly represented. Legal aspects were considered in 51% of the courses, whereas social and economic approaches were only considered in 2.7 and 11% of the courses, respectively. Seedling planting (85%) and nucleation (68%) were the most frequently cited techniques of active restoration, and passive restoration was mentioned in 63% of the courses. Our findings highlight the need for increasing postgraduate courses in areas with nonforest ecosystems, especially due to a lack of knowledge about restoration of these areas. The incorporation of economic and social approaches is highly recommended, considering the importance of these attributes in achieving success in large‐scale restoration initiatives. 相似文献
525.
Alfonso González Ramírez Juan José Calvo Aguirre Pilar Lekuona Ancizar Juan Luis González Oliveras Teresa Marcellán Benavente Ana Ruiz de Gordoa Armendia Antoni Salvá Casanovas Pablo Alcalde Tirado Teresa González Alonso Reyes Padilla Clemente Mercedes Clerencia Sierra Elena Ubis Diez 《Revista espa?ola de geriatría y gerontología》2013
The Workshop on Osteoporosis, Falls and Fractures (GCOF) of The Spanish Geriatrics and Gerontology Society (SEGG) formed a committee in order to review the state of the art on the detection, risk factors and assessment tools for falls, and intervention protocols when falls occurs in nursing homes, long-term hospitals or medium-stay units. The different patient profiles are described in order to make a comprehensive approach to this heterogeneous topic and population, offering a risk classification and specific advice according to these categories. 相似文献
526.
527.
Scott T Bates Jose C Clemente Gilberto E Flores William Anthony Walters Laura Wegener Parfrey Rob Knight Noah Fierer 《The ISME journal》2013,7(3):652-659
Protists are ubiquitous members of soil microbial communities, but the structure of these communities, and the factors that influence their diversity, are poorly understood. We used barcoded pyrosequencing to survey comprehensively the diversity of soil protists from 40 sites across a broad geographic range that represent a variety of biome types, from tropical forests to deserts. In addition to taxa known to be dominant in soil, including Cercozoa and Ciliophora, we found high relative abundances of groups such as Apicomplexa and Dinophyceae that have not previously been recognized as being important components of soil microbial communities. Soil protistan communities were highly diverse, approaching the extreme diversity of their bacterial counterparts across the same sites. Like bacterial taxa, protistan taxa were not globally distributed, and the composition of these communities diverged considerably across large geographic distances. However, soil protistan and bacterial communities exhibit very different global-scale biogeographical patterns, with protistan communities strongly structured by climatic conditions that regulate annual soil moisture availability. 相似文献
528.
529.
Effect of cadmium and calcium treatments on phytochelatin and glutathione levels in citrus plants 总被引:1,自引:0,他引:1
M. F. López‐Climent V. Arbona R. M. Pérez‐Clemente S. I. Zandalinas A. Gómez‐Cadenas 《Plant biology (Stuttgart, Germany)》2014,16(1):79-87
Industry residues, phosphate fertilisers and wastewater as a source of irrigation have considerably increased levels of heavy metals in the soil, mainly cadmium (Cd2+). To test the effects of a calcium (Ca2+) treatment on Cd2+ accumulation and plant tolerance to this heavy metal, plants of two citrus genotypes, Cleopatra mandarin (CM) and Carrizo citrange (CC), were watered with increasing concentrations of Cd2+, and phytochelatin (PC) and glutathione (GSH) content were measured. Both genotypes were able to synthesise PCs in response to heavy metal intoxication, although CM seems to be a better Cd2+ excluder than CC. However, data indicate that CC plants had a higher capacity for regenerating GSH than CM plants. In this context, the effects of Ca2+ treatment on Cd2+ accumulation, plant survival and PC, GSH and oxidised glutathione (GSSG) content were assessed. Data indicate that treatment with Ca2+ had two positive effects on citrus physiology: it reduced Cd+2 uptake into roots and also increased GSH content (even in the absence of Cd2+). Overall, the data indicate that although Cd2+ exclusion is a powerful mechanism to avoid heavy metal build‐up into photosynthetic organs, the capacity to maintain optimum GSH levels to feed PC biosynthesis could also be an important factor in stress tolerance. 相似文献
530.
Hyunwoo Park George Graef Yixiang Xu Patrick Tenopir Tom E. Clemente 《Plant biotechnology journal》2014,12(8):1035-1043
Soybean (Glycine max (L.) Merr) is valued for both its protein and oil, whose seed is composed of 40% and 20% of each component, respectively. Given its high percentage of polyunsaturated fatty acids, linoleic acid and linolenic acid, soybean oil oxidative stability is relatively poor. Historically food processors have employed a partial hydrogenation process to soybean oil as a means to improve both the oxidative stability and functionality in end‐use applications. However, the hydrogenation process leads to the formation of trans‐fats, which are associated with negative cardiovascular health. As a means to circumvent the need for the hydrogenation process, genetic approaches are being pursued to improve oil quality in oilseeds. In this regard, we report here on the introduction of the mangosteen (Garcinia mangostana) stearoyl‐ACP thioesterase into soybean and the subsequent stacking with an event that is dual‐silenced in palmitoyl‐ACP thioesterase and ?12 fatty acid desaturase expression in a seed‐specific fashion. Phenotypic analyses on transgenic soybean expressing the mangosteen stearoyl‐ACP thioesterase revealed increases in seed stearic acid levels up to 17%. The subsequent stacked with a soybean event silenced in both palmitoyl‐ACP thioesterase and ?12 fatty acid desaturase activity, resulted in a seed lipid phenotype of approximately 11%–19% stearate and approximately 70% oleate. The oil profile created by the stack was maintained for four generations under greenhouse conditions and a fifth generation under a field environment. However, in generation six and seven under field conditions, the oleate levels decreased to 30%–40%, while the stearic level remained elevated. 相似文献