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1.
Zhonghua Yi Xue Za Zhi ; 102(12): 833-837, 2022 Mar 29.
Artigo em Chinês | MEDLINE | ID: mdl-35330575

RESUMO

With the explosive growth of deep learning and big data technology, artificial intelligence has penetrated into various fields of medical and health care, bringing efficient and high-quality health services to patients, but also a series of ethical and social governance issues have emerged. In order to avoid and eliminate the foreseeable ethical risks and governance challenges in the development of medical artificial intelligence, the World Health Organization (WHO) first released the Ethical and Governance of Artificial Intelligence for Health guidance on June 28, 2021, aimed to provide a framework for ethical guidelines on the deployment of artificial intelligence in clinical practice. At present, there are still shortcomings and this paper takes Healthy China 2030 agenda and the WHO guidelines as strategic ideas, and proposes to shape a consensus on the ethics of medical artificial intelligence, establish rules for human subjects and ownership of responsibilities, improve the legal and regulatory system, and determine human decision-making and moral subject status, taking into account the cultivation of interdisciplinary talents' ethical literacy and other Chinese inspirations are expected to promote the development of medical artificial intelligence ethics governance.


Assuntos
Inteligência Artificial , Princípios Morais , China , Humanos , Organização Mundial da Saúde
2.
Phys Rev E ; 99(2-1): 023102, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30934280

RESUMO

Small-scale characteristics of turbulence such as velocity gradients and vorticity fluctuate rapidly in magnitude and oscillate in sign. Much work exists on the characterization of magnitude variations, but far less on sign oscillations. While in homogeneous turbulence averages performed on large scales tend to zero because of the oscillatory character, those performed on increasingly smaller scales will vary with the averaging scale in some characteristic way. This characteristic variation at high Reynolds numbers is captured by the so-called cancellation exponent, which measures how local averages tend to cancel out as the averaging scale increases, in space or time. Past experimental work suggests that the exponents in turbulence depend on whether one considers quantities in full three-dimensional (3D) space or uses their one- or two-dimensional cuts. We compute cancellation exponents of vorticity and longitudinal as well as transverse velocity gradients in isotropic turbulence at Taylor-scale Reynolds numbers up to 1300 on 8192^{3} grids. The 2D cuts yield the same exponents as those for full 3D, while the 1D cuts yield smaller numbers, suggesting that the results in higher dimensions are more reliable. We make the case that the presence of vortical filaments in isotropic turbulence leads to this conclusion. This effect is particularly conspicuous in magnetohydrodynamic turbulence, where an increased degree of spatial coherence develops along the direction of an imposed magnetic field.

3.
Genet Mol Res ; 15(2)2016 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-27173341

RESUMO

The purpose of this study was to investigate the association between cellular 2-deoxy-2-[18F]-fluoro-D-glucose ((18)F-FDG) uptake and the expression of several subtypes of glucose transporters (GLUT) and Ki-67 in diffuse large B-cell lymphoma (DLBCL) and natural killer (NK)/T-cell lymphoma (NKTCL). Cell lines were histologically determined to be DLBCL (Raji cells) and NKTCL (Daudi cells), and uptake after pretreatment with (18)F-FDG was determined. Real-time polymerase chain reaction was performed to detect the expression levels of GLUTs 1, 2, 3, 4, and 7 and Ki-67, and to evaluate their association with (18)F-FDG uptake in DLBCL and NKTCL cells. The uptake rates of (18)F-FDG ranged from 18 to 46% (average 30 ± 10.20%) in Raji cells and 25 to 48% (average 35.6 ± 7.57%) in Daudi cells. In DLBCL cells, the expression levels of GLUTs 1, 3, and 7 were significantly correlated with cellular (18)F-FDG uptake rates (Spearman's rank correlation coefficient of 0.667, 0.516, and 0.468, respectively; P < 0.05). In NKTCL cells, the expression levels of GLUTs 1 and 3 were observed to be significantly correlated with cellular (18)F-FDG uptake rates (Spearman's rho of 0.756 and 0.498, respectively; P < 0.05). Ki-67 played no role in (18)F-FDG uptake in Raji or Daudi cells. In conclusion, the data acquired through this preliminary study indicate that GLUT 1 and GLUT 3 contribute to 18F-FDG uptake in DLBCL and NKTCL.


Assuntos
Fluordesoxiglucose F18/farmacocinética , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Antígeno Ki-67/metabolismo , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma de Células T/metabolismo , Linhagem Celular , Glucose/metabolismo , Humanos , Linfoma de Células B/metabolismo , Células T Matadoras Naturais/metabolismo
4.
Proc Natl Acad Sci U S A ; 112(41): 12633-8, 2015 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26424452

RESUMO

We have performed direct numerical simulations of homogeneous and isotropic turbulence in a periodic box with 8,192(3) grid points. These are the largest simulations performed, to date, aimed at improving our understanding of turbulence small-scale structure. We present some basic statistical results and focus on "extreme" events (whose magnitudes are several tens of thousands the mean value). The structure of these extreme events is quite different from that of moderately large events (of the order of 10 times the mean value). In particular, intense vorticity occurs primarily in the form of tubes for moderately large events whereas it is much more "chunky" for extreme events (though probably overlaid on the traditional vortex tubes). We track the temporal evolution of extreme events and find that they are generally short-lived. Extreme magnitudes of energy dissipation rate and enstrophy occur simultaneously in space and remain nearly colocated during their evolution.

5.
Yao Xue Xue Bao ; 25(2): 90-4, 1990.
Artigo em Chinês | MEDLINE | ID: mdl-2239328

RESUMO

In the present paper, effects of scopolia drugs (scopolamine, anisodine, anisodamine) on experimental gastric mucosal lesion models in rats were investigated. Scopolia drugs were found to be effective anti-ulcer agents in three experimental gastric ulcer models (i.e. cold-restraint stress induced ulcer, indomethacin induced ulcer and acetic acid induced chronic ulcer) in rats in a dose dependent manner. Biochemical analysis of gastric juice and blood showed that scopolia drugs could inhibit gastric acid secretion and pepsin activity, increase gastric barrier mucus and concentration of serum gastrin, suggesting that these actions may contribute to its anti-ulcer effect.


Assuntos
Antiulcerosos , Mucosa Gástrica/efeitos dos fármacos , Derivados da Escopolamina/farmacologia , Escopolamina/farmacologia , Alcaloides de Solanáceas/farmacologia , Úlcera Gástrica/patologia , Animais , Feminino , Masculino , Ratos , Ratos Endogâmicos , Escopolamina/uso terapêutico , Úlcera Gástrica/tratamento farmacológico
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