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91.
Mrcia Moraes Cascaes Odirleny dos Santos Carneiro Lidiane Diniz do Nascimento ngelo Antnio Barbosa de Moraes Mozaniel Santana de Oliveira Jorddy Neves Cruz Giselle Maria Skelding Pinheiro Guilhon Eloisa Helena de Aguiar Andrade 《International journal of molecular sciences》2021,22(22)
The present work involves a systematic review of the chemical composition and biological effects of essential oils from the Annonaceae species collected in Brazil from 2011 to 2021. Annonaceae is one of the most important botanical families in Brazil, as some species have economic value in the market as local and international fruit. In addition, the species have useful applications in several areas—for instance, as raw materials for use in cosmetics and perfumery and as medicinal plants. In folk medicine, species such as Annona glabra L. and Xylopia sericea A. St.-Hil. are used to treat diseases such as rheumatism and malaria. The species of Annonaceae are an important source of essential oils and are rich in compounds belonging to the classes of mono and sesquiterpenes; of these compounds, α-pinene, β-pinene, limonene, (E)-caryophyllene, bicyclogermacrene, caryophyllene oxide, germacrene D, spathulenol, and β-elemene are the most abundant. The antimicrobial, anti-inflammatory, antileishmania, antioxidant, antiproliferative, cytotoxic, larvicidal, trypanocidal, and antimalarial activities of essential oils from the Annonaceae species in Brazil have been described in previous research, with the most studies on this topic being related to their antiproliferative or cytotoxic activities. In some studies, it was observed that the biological activity reported for these essential oils was superior to that of drugs available on the market, as is the case of the essential oil of the species Guatteria punctata (Aubl.) R. A. Howard., which showed a trypanocidal effect that was 34 times stronger than that of the reference drug benznidazol. 相似文献
92.
93.
Maria Kelly Venezuela Mônica Carneiro SandovalDenise Aparecida Botter 《Computational statistics & data analysis》2011,55(4):1867-1883
Local influence diagnostics based on estimating equations as the role of a gradient vector derived from any fit function are developed for repeated measures regression analysis. Our proposal generalizes tools used in other studies (
[Cook, 1986] and [Cadigan and Farrell, 2002]), considering herein local influence diagnostics for a statistical model where estimation involves an estimating equation in which all observations are not necessarily independent of each other. Moreover, the measures of local influence are illustrated with some simulated data sets to assess influential observations. Applications using real data are presented. 相似文献
94.
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96.
A.J. Carneiro Molina 《International Journal for Computational Methods in Engineering Science and Mechanics》2016,17(1):46-58
A novel formulation for multiscale finite element analysis of multiphase solids undergoing large strains is proposed in this paper. Within the described homogenization technique no constitutive assumptions are made at the macrolevel. A crucial aspects of the approach is the modeling of antiperiodic traction on the boundary of the representative volume element, condensation technique and the formulation performed on a deformation-driven context whereby the macroscopic deformation gradient is prescribed. Numerical tests on solids with voids demonstrated the robustness of the technique. 相似文献
97.
The classification of colorectal cancers (CRC) is currently based largely on histologically determined tumour characteristics, such as differentiation status and tumour stage, i.e., depth of tumour invasion, involvement of regional lymph nodes and the occurrence of metastatic spread to other organs. These are the conventional prognostic factors for patient survival and often determine the requirement for adjuvant therapy after surgical resection of the primary tumour. However, patients with the same CRC stage can have very different disease-related outcomes. For some, surgical removal of early-stage tumours leads to full recovery, while for others, disease recurrence and metastasis may occur regardless of adjuvant therapy. It is therefore important to understand the molecular processes that lead to disease progression and metastasis and to find more reliable prognostic markers and novel targets for therapy. This review focuses on cell surface proteins that correlate with tumour progression, metastasis and patient outcome, and discusses some of the challenges in finding prognostic protein markers in CRC. 相似文献
98.
Nadya Dencheva M. Jovita Oliveira Olga S. Carneiro António S. Pouzada Zlatan Denchev 《应用聚合物科学杂志》2010,115(5):2918-2932
The preparation of microfibrillar composites (MFCs) based on oriented blends of polyamide 6 (PA6) and high‐density polyethylene (HDPE) is described. By means of conventional processing techniques, the PA6 phase was transformed in situ into fibrils with diameters in the upper nanometer range embedded in an isotropic HDPE matrix. Three different composite materials were prepared through the variation of the HDPE/PA6 ratio with and without a compatibilizer: MFCs reinforced by long PA6 fibrils arranged as a unidirectional ply; MFCs containing middle‐length, randomly distributed reinforcing PA6 bristles; and a nonoriented PA6‐reinforced material in which the PA6 phase was globular. The evolution of the morphology in the reinforcing phase (e.g., its visible diameter, length, and aspect ratio) was followed during the various processing stages as a function of the blend composition by means of scanning electron microscopy. Synchrotron X‐ray scattering was used to characterize selected unidirectional ply composites. The presence of transcrystalline HDPE was demonstrated in the shell of the reinforcing PA6 fibrils of the final MFCs. The impact of the compatibilizer content on the average diameter and length of the fibrils was assessed. The influence of the reinforcing phase on the tensile strength and Young's modulus of the various composites was also evaluated. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
99.
Amanda Cia Hetzl Fabio Montico Raisa Misitieri Larissa Kido Eduardo Cândido Athanase Billis Ubirajara Ferreira Valeria Ha Cagnon 《Microscopy research and technique》2013,76(3):321-330
The objective was to characterize and associate the receptor reactivities of fibroblastic growth factor (FGF)‐2, FGF‐7, FGF‐8, epidermal growth factor (EGF), α‐actin and vimentin in relation to the androgen receptor (AR), α and β estrogen receptors (ERα and ERβ), and prolactin receptor in the prostate of elderly men showing low‐ and high‐grade adenocarcinoma. Thirty prostatic samples were taken from 60‐ to 90‐year‐old patients without prostatic lesions and with low‐grade cancer and high‐grade cancer, from the University Hospital, School of Medicine, the State University of Campinas. The results showed that increased FGF‐2, FGF‐7, and FGF‐8 receptor reactivities and decreased AR reactivity were verified in both high‐ and low‐grade cancer. However, the FGF‐8 receptor showed greater involvement at the beginning of the malignancy alterations. Increased EGF receptor (EGFR) reactivity and diminished α‐actin immunohistochemistry were identified in both cancer groups. Also, increased ERα, PR, and vimentin receptors were verified in both cancer groups. To conclude, the ERα involvement in the reactive stroma activation led to a microenvironment, which was favorable to cancer progression, due to maximizing stromal imbalance. The prolactin could be related to cancer progression due to its interaction with ERα action, indicating that this hormone could be a relevant target to prevent the estrogenic effects in the prostatic lesions. Both FGF receptor (FGFR)‐2 and FGFR‐8 play a fundamental role in the early stages of prostate cancer, suggesting that these molecules could be a promising therapeutic target. The differential localization of the fibroblastic factors between the prostatic epithelium and stroma of elderly men, who presented prostate cancer, could indicate a favorable distinction for tumoral progression. Microsc. Res. Tech. 76:321–330, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
100.
In this article, the chemical foaming of fluorinated ethylene propylene copolymers (FEP) is investigated. For the laboratory scale foam extrusion process, a chemical blowing agent adapted to the high melting temperature of FEP had to be found. Foaming experiments were carried out varying process and material parameters. Foam densities as well as cellular structures were analyzed to characterize how the parameters influence the foaming behavior of the FEP melt. An increasing rate of the foam extrusion caused an augmentation of cell numbers at a simultaneous decrease of their diameters. Moreover, a pronounced reduction of the foam density with increasing output rate could be observed. Changing the temperature of the foam extrusion, an optimum in density reduction and homogeneity of the cell size was found. Furthermore, the influence of an appropriate nucleation agent on the resulting geometry and amount of cells was investigated. Though the chemical blowing agent itself can act as an implement for nucleating cell growth, an addition of 10 wt% of calcium fluoride particles showed a significant augmentation in cell quantity. For the chemical foam extrusion process, three FEP with different viscosities were characterized. With decreasing viscosity, a reduction in foam density could be observed for all temperatures. POLYM. ENG. SCI., 47:1740–1749, 2007. © 2007 Society of Plastics Engineers 相似文献