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151.
Gypsum and sulfur have been used as amendments for application in sodic and saline sodic soils, although gypsum is not effective in soil pH reduction. In this study the combined effects of elemental sulfur inoculated with Acidithiobacillus (S*) and gypsum (G) in chemical attributes of a Brazilian solodic soil was evaluated. The treatments consisted in addition of S* and G in various levels (0, 0.8, 1.6, 2.4, and 3.2 t ha−1) and different mixing proportions (100:0, 75:25, 50:50, 25:75, and 100:0), acting during 15, 30, and 45 days. Sulfur inoculated with Acidithiobacillus (S*) markedly reduced soil pH in the leaching solution, especially when applied in the highest levels. Gypsum or sulfur applied individually was not satisfactory for soil reclamation. At 15 days of incubation Na+, Ca2+, and Mg2+ showed higher values in the leaching solution, and a marked decrease was observed in the leaching solution at 30 days. Reduction in soil electrical conductivity and in exchangeable Na+, Ca2+, and Mg2+ was observed and in a general way best results were achieved with S* : G in the ratio 50:50, using 2.4 and 3.2 t ha−1. Sulfur with Acidithiobacillus was more effective than gypsum in decreasing soil pH, and sulfur applied with gypsum in the proportion 50:50 showed the best results in relation to exchangeable sodium and electrical conductivity and showed values below those used for classification as sodic soils.  相似文献   
152.
Recent in vitro studies suggest that propolis and some of its phenolic components are able to inhibit Helicobacter pylori growth. To date, there are no clinical studies. AIMS: To evaluate the effect of Brazilian green propolis on H. pylori-infected individuals. PATIENTS AND METHODS: Eighteen (11 females, 7 males, mean age 47 years) participants were included. Before treatment, all participants were submitted to gastroscopy, and H. pylori infection was confirmed by histology, urease test, and (13)C-urea breath test (UBT). Participants with UBT showing a delta over baseline (DOB) value higher than 4 per thousand were considered positive for H. pylori infection. Twenty drops from an alcoholic preparation of Brazilian green propolis were administered three times a day for 7 days. Clinical evaluation and UBT were performed at 1-3 days and at 40 days after the end of therapy to evaluate H. pylori suppression or eradication, respectively. RESULTS: All participants took all medication and completed the study. Eighty-three percent of the subjects did not succeed in suppressing or eradicating H. pylori. Two participants reached partial suppression after treatment, but became positive again at UBT performed 40 days after treatment. Another participant presented negative at UBT 40 days after treatment, not confirmed by a second UBT performed 100 days after treatment. CONCLUSIONS: Brazilian green propolis used in popular dose showed minimal effect on H. pylori infection. Larger studies with longer duration, larger dose, and different frequency of administration of propolis extract should be undertaken to define its role on H. pylori therapy.  相似文献   
153.
Objective: To present the current status of geriatric dentistry in Brazil. Background: In 2001, the Brazilian Dental Council established a new specialty: geriatric dentistry. This decision was based on the increase in both the elderly population and the demand for dental treatment of this cohort. Materials and methods: Data were obtained through online searches of the Brazilian Dental Council and the Brazilian Institute of Geography and Statistics. Results: Brazil has 170 dental schools offering around 14 000 undergraduate vacancies every year. At the postgraduate level, there are 19 recognised dental specialties, one of which is geriatric dentistry, comprising 18 certificate programmes, with the potential to produce 216 new specialists every 18 months. The dentist/habitant ratio was 1:870, higher than that recommended by the Word Health Organization. The Brazilian population consists of around 14.5 million elderly people (8.6%). There were 124 specialists in geriatric dentistry distributed irregularly throughout the country. The specialist/elderly population rate was 1:117 249. At the undergraduate level, this new specialty is not included in the curricula of most dental schools in Brazil. Conclusions: Geriatric dentistry should be included in the undergraduate curricula of dental schools in Brazil. Postgraduate degree courses should be developed to produce more clinical academics and researchers in this field.  相似文献   
154.
The rates of invasive pneumococcal disease (IPD), serotype distribution and antimicrobial susceptibility prior to and after the introduction of the heptavalent pneumococcal conjugate vaccine in Portuguese children were evaluated. The changes in incidence of IPD in children under 1 year old between the two periods of the study was not significant (P=0.53), despite the 21% decline. In children under 18 years old there was a 27.7% decrease in vaccine serotypes. All nonvaccine serotypes increased 71.4%. The decrease in vaccine serotypes was more impressive during the first year of life (-54.8%) than for children between 1 and 5 years of age (-19.1%). Among children under 1 year old, penicillin nonsusceptible isolates declined between the two periods of the study (47.2% vs. 25.0%) (P=0.03), as did those of cefotaxime and ceftriaxone nonsusceptible isolates. No changes were observed for isolates nonsusceptible to tetracycline and macrolides. The serotypes of these nonsusceptible isolates differed after the introduction of vaccine (P=0.01). Multiresistance increased 57.1% after the introduction of vaccine. Multiresistant isolates with vaccine serotype declined 42.9% (P<0.001), and nonvaccine serotypes appeared during the vaccination period (P<0.001). These findings suggest a replacement of vaccine serotypes by nonvaccine serotypes, mainly among nonsusceptible isolates.  相似文献   
155.
ATPases, an important target of insecticides, are enzymes that hydrolyze ATP and use the energy released in that process to accomplish some type of cellular work. Pachymerus nucleorum (Fabricius) larvae possess an ATPase, that presents high Ca-ATPase activity, but no Mg-ATPase activity. In the present study, the effect of zinc and copper ions in the activity Ca-ATPase of that enzyme was tested. More than 90% of the Ca-ATPase activity was inhibited in 0.5 mM of copper ions or 0.25 mM of zinc ions. In the presence of EDTA, but not in the absence, the inhibition by zinc was reverted with the increase of calcium concentration. The inhibition by copper ions was not reverted in the presence or absence of EDTA. The Ca-ATPase was not inhibited by treatment of the ATPase fraction with copper, suggesting that the copper ion does not bind directly to the enzyme. The results suggest that zinc and copper ions form a complex with ATP and bind to the enzyme inhibiting its Ca-ATPase activity.  相似文献   
156.

A new parasitic copepod, Tiddergasilus bipartitus n. sp. (Copepoda, Ergasilidae), is described herein based on three adult females found attached to the gills of the yellow-tail lambari Astyanax lacustris (Lütken), sampled in Pardo River, municipality of Botucatu, São Paulo State, Brazil. Tiddergasilus bipartitus n. sp. was recognized as a new member of the monotypic genus Tiddergasilus Marques & Boeger, 2018 by having: antennule 6-segmented; maxillary basis armed with 2 terminal teeth and ornamented with multiple spinules; second and third leg both with endopod 3-segmented. The new copepod can be distinguished from its congener, Tiddergasilus iheringi (Tidd, 1942), by the morphology of the antennal claw, number of somites/segments in abdomen and fourth leg, and by the ornamentation of the first leg. This report expands the geographic distribution and diversity of fish species parasitized with Tiddergasilus spp. in Brazil. Moreover, it also represents the first report of an ergasilid species in the Pardo River. A list of diagnostic features for the Brazilian species of Ergasilus von Nordmann, 1832 is provided herein, in order to aid comparisons with the species of this complex genus.

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157.

The present study describes a new regeneration system based on somatic embryogenesis from mature endosperm Passiflora cincinnata Mast. cultures. Moreover, the morpho-agronomic and phenological traits, as well as enzymatic activity of regenerated triploid emblings are compared to those of diploids. Mature endosperms were cultured on Murashige and Skoog medium supplemented with various concentrations (4.5–45.2 µM) of 2,4-dichlorophenoxyacetic acid (2,4-D) and 4.5 μM 6-benzylaminopurine (BA). No plant growth regulators were included in the control group. Embryogenic calli were observed only in treatments supplemented with 13.6 and 18.1 µM 2,4-D?+?4.5 µM BA, with the highest number of somatic embryos per explant and regenerated plants (emblings) obtained with 18.1 µM 2,4-D. Most emblings (70%) were triploid (2n?=?3x?=?27), with a DNA amount (4.38 pg) similar to that of endosperm and 1.5 times greater than in diploid P. cincinnata seedlings (2n?=?2x?=?18), that contained 2.98 pg of DNA. While the number of organs and/or structures was akin to that in diploids, triploid emblings generally exhibited larger and longer vegetative and floral structures. The flower lifespan was also slightly altered by triploidy, nectar concentration was 27% higher, and the activity of plant defense enzymes β-1,3-glucanase and polyphenol oxidase was 29.8% and 22.1% higher. This study describes a new regeneration system for the production of phenotypic variants of this ornamental passion fruit species, opening new perspectives for future studies on genetic passion fruit breeding.

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158.
Glycoconjugate Journal - Diabetes Mellitus (DM) is both, correlated and a known risk factor for colorectal cancer (CRC). Besides favoring the incidence of CRC, DM also accelerates its progression,...  相似文献   
159.
Rivers connect the carbon cycle in land with that in aquatic ecosystems by transporting and transforming terrestrial organic matter (TeOM). The Amazon River receives huge loads of TeOM from the surrounding rainforest, promoting a substantial microbial heterotrophic activity and consequently, CO2 outgassing. In the Amazon River, microbes degrade up to 55% of the lignin present in the TeOM. Yet, the main microbial genomes involved in TeOM degradation were unknown. Here, we characterize 51 population genomes (PGs) representing some of the most abundant microbes in the Amazon River deriving from 106 metagenomes. The 51 reconstructed PGs are among the most abundant microbes in the Amazon River, and 53% of them are not able to degrade TeOM. Among the PGs capable of degrading TeOM, 20% were exclusively cellulolytic, while the others could also oxidize lignin. The transport and consumption of lignin oxidation byproducts seemed to be decoupled from the oxidation process, being apparently performed by different groups of microorganisms. By connecting the genomic features of abundant microbes in the Amazon River with the degradation machinery of TeOM, we suggest that a complex microbial consortium could explain the quick turnover of TeOM previously observed in this ecosystem.  相似文献   
160.
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