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11.
In Brazil, every study involving human beings is required to produce an informed consent form that must be signed by study participants: this is stated in Resolution 196/96. 1 Consent must be obtained through a specific structured process. Objective: To present the opinions of women regarding how the process of obtaining informed consent should be conducted when women are invited to participate in studies on contraceptive methods. Subjects and Methods: Eight focus groups were conducted, involving a total of 51 women living in the metropolitan region of Campinas. The women involved in the study were either participating in a clinical trial in the area of women’s health or had participated in such a trial in the previous 12 months. A thematic guide was used to conduct the focus group discussions; the discussions were recorded, transcribed and a thematic analysis performed. Results: In general, the person who invites a woman to participate in a study should be a member of the research team but not the principal investigator. Information relating to the study should be given orally and in writing, both individually and in the group setting. Study volunteers should be informed about, among other things, the risks, possible side effects and discomforts, including long‐term effects. The use of audiovisual aids to provide information was suggested. Conclusion: The process for obtaining informed consent was seen as a means of establishing a relationship between the volunteers and the investigator/research team. The information that the study participants expected to be given coincides with the requirements established under Resolution 196/96. The use of audiovisual aids would improve understanding of the information provided.  相似文献   
12.
Biomass estimates of primary and different ages of secondary vegetation are reported for a tropical forest region in Rondônia, Western Brazilian Amazon. The estimates are based on published allometric equations, and on vegetation composition and allometric data collected in areas of primary forest and secondary vegetation of ages 2, 3, 5, 9, 11, 16 and 18 years. Primary forest biomass estimates varied from 290 to 495 t ha–1. Secondary vegetation biomass estimates accounted for 40–60% of the primary forest biomass after 18 years of abandonment. Secondary growth rates in lightly used areas are estimated to have varied from 6.6 to 8.7 t ha–1 y–1 between the third and the eighteenth years after abandonment. CO2 sequestration by regrowing vegetation is discussed for two scenarios of land abandonment.  相似文献   
13.
The aim of this study was to investigate whether product label information “produced with organic ingredients” and “stabilization technology” affects consumer acceptability of vegetable soups. Three focus group interviews were preliminarily conducted in order to gain information about the appropriate terminology to use in the next consumer test. In all, 109 subjects were recruited by means of a background questionnaire. They were then divided into three groups according to age, gender and soup preference. Each group evaluated three different types of soup in two phases, first blind and then with information. At the end of the second phase, the participants filled in a conjoint analysis questionnaire. The results demonstrated that if consumers were informed that soup is prepared with organic ingredients, they would improve their acceptability scores, whatever the soup type. Stabilization technology information had no effect. Conjoint results revealed that consumers appreciate soups made with organic legumes and cereals and without seasoning. However, differences among subgroups were found.  相似文献   
14.
A recessive maize mutant with disrupted seedling developmentwas isolated following transpositional mutagenesis with Mutator.This mutant, initially identified during germination on thebasis of abnormal growth of the scutellar node, was designatedlsn1 (l arge s cutellar n ode). The mutant seedling exhibitsan enlarged primary root with a longitudinal groove and multipleseparate root tips. The mutant root is shorter than normal,because of defective cell elongation, and lacks lateral roots.The mutant plant shows defective leaves and reduced internodeelongation. Histological analyses on primary root, shoot, scutellarnode and juvenile leaves revealed a series of defects, all relatedto an irregular differentiation of vascular elements. In addition,in situ hybridization of mutant leaves demonstrates an abnormalpattern of expression of Knotted-1, a marker of meristem function.The presence of multiple roots fused together can be interpretedas suppression of the negative control responsible for the differentiationof only one root primordium. Therefore, the data obtained onseedlings of lsn1 point to a relationship between meristem activity,vascular differentiation and auxin polar transport, and mayallow the identification of a gene which is active during embryogenesis.Copyright2000 Annals of Botany Company Auxin, defective seedling, maize, meristem activity, vascular differentiation, Zea mays.  相似文献   
15.
The rodent genus Oecomys (Sigmodontinae) comprises ~16 species that inhabit tropical and subtropical forests in Central America and South America. In this study specimens of Oecomys paricola Thomas, 1904 from Belém and Marajó island, northern Brazil, were investigated using cytogenetic, molecular and morphological analyses. Three karyotypes were found, two from Belém (2n = 68, fundamental number (FN) = 72 and 2n = 70, FN = 76) and a third from Marajó island (2n = 70, FN = 72). No molecular or morphological differences were found between the individuals with differing cytotypes from Belém, but differences were evident between the individuals from Belém and Marajó island. Specimens from Belém city region may represent two cryptic species because two different karyotypes are present in the absence of significant differences in morphology and molecular characteristics. The Marajó island and Belém populations may represent distinct species that have been separated for some time, and are in the process of morphological and molecular differentiation as a consequence of reproductive isolation at the geographic and chromosomal levels. Thus, the results suggest that O. paricola may be a complex of species.  相似文献   
16.
The base chromosome number of x = 11 is the most probable in all the subtribes included in tribe Phaseoleae, although some aneuploid reduction is evident in Collaea and Galactia (Diocleinae) and chromosome duplications are seen in Amphicarpaea, Cologania and Glycine (Glycininae). The aims of this study were to improve the cytological knowledge of some species of Collaea and Galactia and to examine the anomalous counts reported for Calopogonium (Glycininae) and verify its taxonomic position. In addition, a molecular phylogeny was constructed using nuclear ribosomal DNA sequences (internal transcribed spacer region), and the chromosome number was optimized on the topology. In this work, the chromosome counts for Galactia lindenii, Galactia decumbens and Collaea cipoensis (all 2n = 20), and Calopogonium sericeum (2n = 22) are reported for the first time. The new reports for Galactia and Collaea species are in agreement with the chromosome number proposed for subtribe Diocleinae. The study rejects the concept of a cytologically anomalous Calopogonium and, based on the phylogenetic analysis, corroborates the position of this genus within subtribe Glycininae. The ancestral basic chromosome number of x = 11 proposed for Phaseoleae is in agreement with the evolutionary pathway of chromosome numbers analysed in this work. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 336–341.  相似文献   
17.
Heat stress in grapevine: the pros and cons of acclimation   总被引:1,自引:0,他引:1       下载免费PDF全文
Heat stress is a major limiting factor of grapevine production and quality. Acclimation and recovery are essential to ensure plant survival, and the recovery mechanisms can be independent of the heat response mechanisms. An experimental set up with and without acclimation to heat followed by recovery [stepwise acclimation and recovery (SAR) and stepwise recovery (SR), respectively] was applied to two grapevine varieties, Touriga Nacional (TN), and Trincadeira (TR), with different tolerance to abiotic stress. Major differences were found between leaves of SAR and SR, especially after recovery; in SAR, almost all parameters returned to basal levels while in SR they remained altered. Acclimation led to a swifter and short‐term antioxidative response, affecting the plant to a lesser extent than SR. Significant differences were found among varieties: upon stress, TN significantly increased ascorbate and glutathione reduction levels, boosting the cell's redox‐buffering capacity, while TR needed to synthesize both metabolites, its response being insufficient to keep the redox state at working levels. TR was affected by stress for a longer period and the up‐regulation pattern of antioxidative stress genes was more obvious. In TN, heat shock proteins were significantly induced, but the canonical heat‐stress gene signature was not evident probably because no shutdown of the housekeeping metabolism was needed.  相似文献   
18.
Five highly polimorphic microsatellite markers for Symphonia globulifera were developed from enriched repeat libraries screened for microsatellite repeats. An average of 5.8 alleles per locus and expected heterozygosity ranging from 0.649 to 0.806 were found in a sample of 12 S. globulifera individuals from the Tapajos National Forest, in the state of Pará in the Brazilian Amazon. These loci are being used for analysis of precise paternity testing, estimation of gene flow and parentage coefficients in a managed forest in Pará, Brazil, as part of the Dendrogene Project.  相似文献   
19.
A genomic library from the commercial diploid cultivar ‘Ouro’ (Musa acuminata), enriched for CT‐ and GT‐repeats, was used to isolate and characterize 23 microsatellite loci. These loci were tested in 10 Musa genotypes, representing various Musa genomic groups with distinct ploidy level. The number of alleles per locus ranged from one to seven, and 20 loci were highly informative. Four loci appeared to amplify B genome‐specific alleles, while three loci seemed to be absent in the B genome. The polymorphism revealed by these loci will be extremely useful for genetic mapping, marker‐assisted selection, germplasm characterization and evolutionary studies in Musa.  相似文献   
20.
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