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1.
I T Toledo e Souza B L Wajchenberg F Prestes Cesar J S Almeida Neto 《Hormones et métabolisme》1983,15(12):575-580
Insulin and C-peptide (free insulin and C-peptide in insulin-treated patients) were measured after glucose stimulation in nine Type II diabetics on chlorpropamide, eleven insulin-treated maturity-onset diabetics and in 8 normal controls. Dissociation between C-peptide and insulin response to glucose was observed in several diabetics. The relation between incremental molar areas under C-peptide and insulin curves, after glucose challenge (delta CPR - delta IRI/delta CPR) were used to evaluate the hepatic insulin extraction in all but the insulin-treated diabetics. The lower insulin requirements and better control of the short-duration insulin-treated maturity-onset diabetics in relation to the long-term ones could not be explained either by the residual insulin secretion or by the level of "insulin antibodies". The chlorpropamide-responsive patients presented higher insulin levels after the glucose challenge and a lower hepatic insulin extraction than the non-responsive ones. 相似文献
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Janaine Almeida Neto Daniel Amando Nery Katia Simoni Bezerra Lima Maria Eduarda Gomes da Cruz Silva Tarcísio Cícero de Lima Araújo Nathália Andrezza Carvalho de Souza Rodolfo Hideki Vicente Nishimura Camila de Souza Araújo Ana Paula de Oliveira Jackson Roberto Guedes da Silva Almeida Larissa Araújo Rolim 《化学与生物多样性》2023,20(3):e202201039
This article describes the phytochemical study of Cannabis sativa roots from northeastern Brazil. The dried plant material was pulverized and subjected to exhaustive maceration with ethanol at room temperature, obtaining the crude ethanolic extract (Cs-EEBR). The volatile compounds were analyzed by gas chromatography coupled with mass spectrometry (GC/MS), which allowed to identify 22 compounds by comparing the linear retention index (LRI), the similarity index (SI) and the fragmentation pattern of the constituents with the literature. By this technique the major compounds identified were: friedelan-3-one and β-sitosterol. In addition, two fractions were obtained from Cs-EEBR by classical column chromatography and preparative thin layer chromatography. These fractions were analyzed by NMR and IR and together with the mass spectrometry data allowed to identify the compounds: epifriedelanol, friedelan-3-one, β-sitosterol and stigmasterol. The study contributed to the phytochemical knowledge of Cannabis sativa, specifically the roots, as there are few reports on the chemical constituents of this part of the plant. 相似文献
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C Camaioni Neto J M Steim P S Sarin D K Sun N N Bhongle R K Piratla J G Turcotte 《Biochemical and biophysical research communications》1990,171(1):458-464
Disodium palmityl phosphonoformate, a novel lipid phosphoester of the anti HIV agent phosphonoformate (foscarnet), inhibits HIV replication in H9 cells and syncytia formation in MOLT-3 cells as effectively as foscarnet itself, as shown by dose-response data from assays for expression of p17 and p24 viral antigens and syncytia formation. Protein binding studies indicate that in serum, the derivative exists bound to albumin and the lipoproteins, and would therefore be likely to exhibit improved serum lifetime in vivo. 相似文献
5.
Dulce E. Oliveira Ana Lúcia C. Santos Neto Anita D. Panek 《Analytical biochemistry》1981,113(1):188-192
A quantitative in situ assay of yeast α-glucosidase involving permeabilization of the cells by freezing and thawing is described. The assay was applied to different strains in different physiological states and was shown to give results comparable to those obtained with total cell homogenates. The primary advantage of the in situ assay was the possibility of analyzing a large number of samples from the same culture during a growth curve using a very reduced cell mass. 相似文献
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Ichnology and sedimentology of a tide‐influenced delta in the Ordovician from the northeastern Alborz range of Iran (Kopet Dagh region) 下载免费PDF全文
Aram Bayet‐Goll Carlos Neto de Carvalho 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2016,49(3):327-350
The Middle–Late Ordovician Ghelli Formation in the Kopet Dagh region northeastern Alborz range of Iran is composed of siliciclastic rocks deposited in a variety of turbidite to marginal marine environments (deep marine clastic fan and related environments and prodelta, distal delta front, proximal delta front and distributary channels). The ichnology of the middle member of the Ghelli Formation is here reported. Combined sedimentological and ichnological analysis allows recognition of a tide‐influenced deltaic succession in the middle member of the Ghelli Formation consisting of three main facies associations: lower distributary channels, delta front and prodelta facies. Twenty‐two ichnogenera have been identified in this marginal marine succession: Arenicolites, Arthrophycus, Bergaueria, Chondrites, Conichnus, Cruziana, Cylindrichnus, Didymaulichnus, Diplichnites, Diplocraterion, Helminthopsis, Gyrochorte, Lockeia, Macaronichnus, Monomorphichnus, Palaeophycus, Planolites, Rosselia, Rusophcus, Skolithos, Teichichnus and ?Scolicia. Their distribution is clearly linked with lithofacies and depositional palaeoenvironments. The ichnological analysis reveals that the trace fossil suites developed in these environments indicate low diversity and low to moderate abundance of burrows, poor development of tiering and sporadic distribution. Low ichnodiversity and low bioturbation intensities with higher bioturbation clusters consist of facies‐crossing ichnogenera, and the impoverishment of suspension‐feeding trophic types indicates ‘stressed’, non‐archetypal expression of the Cruziana ichnofacies. The periodic higher intensities of bioturbation due to variations in hydrodynamic regimes of tidal currents reflect the archetypal of the Cruziana ichnofacies (and rare Skolithos ichnofacies). 相似文献
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Ana Luiza Menegatti Pavan Maria Eugênia Dela Rosa Guilherme Giacomini Fernando Antonio Bacchim Neto Seizo Yamashita Luiz Carlos Vulcano Sergio Barbosa Duarte José Ricardo de Arruda Miranda Diana Rodrigues de Pina 《PloS one》2016,11(4)
Digital radiographic imaging is increasing in veterinary practice. The use of radiation demands responsibility to maintain high image quality. Low doses are necessary because workers are requested to restrain the animal. Optimizing digital systems is necessary to avoid unnecessary exposure, causing the phenomenon known as dose creep. Homogeneous phantoms are widely used to optimize image quality and dose. We developed an automatic computational methodology to classify and quantify tissues (i.e., lung tissue, adipose tissue, muscle tissue, and bone) in canine chest computed tomography exams. The thickness of each tissue was converted to simulator materials (i.e., Lucite, aluminum, and air). Dogs were separated into groups of 20 animals each according to weight. Mean weights were 6.5 ± 2.0 kg, 15.0 ± 5.0 kg, 32.0 ± 5.5 kg, and 50.0 ± 12.0 kg, for the small, medium, large, and giant groups, respectively. The one-way analysis of variance revealed significant differences in all simulator material thicknesses (p < 0.05) quantified between groups. As a result, four phantoms were constructed for dorsoventral and lateral views. In conclusion, the present methodology allows the development of phantoms of the canine chest and possibly other body regions and/or animals. The proposed phantom is a practical tool that may be employed in future work to optimize veterinary X-ray procedures. 相似文献
8.
Species diversity of the genus Osmundea (Ceramiales,Rhodophyta) in the Macaronesian region 下载免费PDF全文
María Machín‐Sánchez Florence Rousseau Line Le Gall Valéria Cassano Ana I. Neto Abel Sentíes Mutue T. Fujii María Candelaria Gil‐Rodríguez 《Journal of phycology》2016,52(4):664-681
Species diversity within the genus Osmundea in the Macaronesian region was explored by conducting a comprehensive sampling in the Azores, the Canary, and the Madeira archipelagos. Toward identification, all specimens were first observed alive to verify the absence of corps en cerise, a diagnostic character for the genus and morphometric data were measured (thallus length and width, first‐order branches length and width, branchlets length and width, cortical cell length and width in surface view, cortical cell length and width in transverse section). Specimens were sequenced for COI‐5P (39 specimens) and three species delimitation methods (Generalized Mixed Yule Coalescent, Automatic Barcode Gap Discovery method, and Poisson Tree Processes) were used to assess the threshold between infra‐ and interspecific relationships. Subsequently, one or several sequences of plastid‐encoded large subunit of RuBisCO (21 specimens) per delimited species were generated to assess the phylogenetic relationships among Macaronesian Osmundea. Moreover, for each delineated species, vegetative and reproductive anatomy was thoroughly documented and, when possible, specimens were either assigned to existing taxa or described as novel species. This integrative approach has provided data for (i) the presence of O. oederi, O. pinnatifida, and O. truncata in Macaronesia; (ii) the proposal of two novel species, O. prudhommevanreinei sp. nov. and O. silvae sp. nov.; and (iii) evidence of an additional species referred as “Osmundea sp.1,” which is a sister taxon of O. hybrida. 相似文献
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Using functional traits to investigate the determinants of crustacean zooplankton community structure 总被引:1,自引:0,他引:1
Understanding the various processes contributing to community assembly is among the central aims of ecology. As a means of exploring this topic we quantified the relative influences of habitat filtering and competition in establishing patterns of community functional trait diversity across a landscape of lakes. Habitat filtering has been invoked in shaping community structure when co‐occurring taxa are more similar in their traits than expected by chance (under‐dispersion), and competition has been inferred as a structuring agent when co‐occurring taxa are less similar (over‐dispersion). We tested these hypotheses in crustacean zooplankton communities using a functional trait‐based approach based on five traits defining zooplankton feeding and habitat preferences across 51 lakes spanning several large limnological gradients. In general, zooplankton communities were functionally less diverse than random assemblages created from the same regional species pool. Furthermore, functional diversity was strongly correlated with variables related to lake productivity, suggesting that access to resources was the chief habitat filtering process constraining zooplankton functional diversity. This pattern was driven by the predominantly herbivorous cladocerans as opposed to the more commonly omnivorous, and sometimes carnivorous, copepods. 相似文献