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1.
Artigo em Inglês | MEDLINE | ID: mdl-31100895

RESUMO

Sustainable transboundary water governance is often challenged by conflicts between agents, which necessitates the design of cooperative and self-enforcing alternatives to facilitate equitable water distribution. The Nash bargaining approach, which originated from game theory, could offer a good mathematical framework to simulate strategic interactions among involved agents by considering individual rational benefits. Given that river-sharing problems often involve multiple self-interested agents, the asymmetric Nash bargaining solution (ANBS) could be used to describe agents' powers, as determined by disparate social, economic, and political as well as military status, and ensure win-win strategies based on individual rationality. This paper proposed an asymmetric bargaining model by combining multi-criteria decision making, bankruptcy theory, and the ANBS for water distribution in the transboundary river context. The Euphrates River Basin (ERB) with three littoral states was used as a case study. Turkey has the highest bargaining power in ERB negotiation since it dominates in terms of economic strength, political influence, and military capacity, whereas in the two downstream countries these aspects are limited due to their internal political fragmentation and weaker military status. The water satisfaction percentages of Turkey, Syria, and Iraq under the best alternative are 96.30%, 84.23%, and 40.88%, respectively. The findings highlight the necessity for synthetically considering the agent's disagreement utility and asymmetrical power when negotiating over water allocation.


Assuntos
Teoria dos Jogos , Negociação , Alocação de Recursos , Recursos Hídricos , Tomada de Decisões , Iraque , Rios , Síria , Turquia , Abastecimento de Água
2.
J Opt Soc Am A Opt Image Sci Vis ; 36(4): 628-635, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31044982

RESUMO

The incidence of melanoma in children is extremely rare. However, there is convincing evidence supporting a higher risk of developing melanoma in individuals who have experienced excessive sun exposure during their childhood. A possible explanation for this phenomenon is that prior to puberty, the melanocyte stem cells in the bulge region of hair follicles are much shallower in the dermis, resulting in their increased vulnerability to sun exposure. To validate this hypothesis, a Monte Carlo simulation of light transport is applied to quantify the dose of solar UV power absorbed in the stem-cell layers at different depths in both child and adult skins. The simulated results suggest that the stem cells in vellus hair follicles would absorb over 250 times higher UV photons than those in the terminal hair follicles. Due to the thinner epidermis in child skin, the stem cells in vellus hair follicles absorb about 1.9 and 3.2 times greater ultraviolet A and ultraviolet B, respectively, than those in adult skin. These findings provide a possible explanation to why children are particularly vulnerable to sun exposure.


Assuntos
Folículo Piloso/patologia , Melanoma/patologia , Modelos Biológicos , Exposição à Radiação/efeitos adversos , Células-Tronco/patologia , Células-Tronco/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Absorção de Radiação , Carcinogênese/efeitos da radiação , Humanos , Método de Monte Carlo , Pele/patologia , Pele/efeitos da radiação
3.
Clin Res Hepatol Gastroenterol ; 42(6): 564-569, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30145281

RESUMO

OBJECTIVE: To obtain a reasonable drainage after laparoscopic common bile duct exploration (LCBDE) for the treatment of choledocholithiasis. METHODS: Data of 350 consecutive patients who underwent LCBDE in our hospital from January 2014 to December 2016 were retrospectively reviewed. All the patients were divided into three groups according to different drainage types after LCBDE, including T-tube group with 116 cases, primary closure (PC) group with 114 cases and stent insertion group with 120 cases. Operative parameters and outcomes were compared. RESULTS: The operative time was no significant difference between the T-tube group (106.71 ± 5.19 min), PC group (105.46 ± 5.77 min) and stent insertion group (106.88 ± 5.91 min) (F = 2.175, P = 0.115). The postoperative hospital stay was significantly shorter in the stent insertion group (5.62 ± 0.70 d) than in the T-tube group (7.79 ± 0.85 d) and PC group (7.60 ± 0.80 d) (F = 279.649, P = 0.000). The hospitalization cost was significantly less in the stent insertion group (19,432.78 ± 661.74 yuan) than in the T-tube group (22,059.90 ± 697.98 yuan) and PC group (21,927.20 ± 772.02 yuan) (F = 512.492, P = 0.000). The incidence of postoperative biliary-specific complications was 2.59% (3/116 cases) in the T-tube group, 2.63% (3/114 cases) in the PC group, and 0% (0/120 cases) in the stent insertion group, but this difference was not statistically significant (χ2 = 3.177, P = 0.204). The return to normal levels of postoperative liver function tests (LFTs) was significantly faster in the stent insertion group and T-tube group than in the PC group (P < 0.05). The number of 314 patients were followed up for a median time of 20 months (range from 1-48 months), and no biliary stricture, cholangitis or stone recurrence occurred in these patients during that time. CONCLUSIONS: Stent insertion shows better results when compared with T-tube drainage and primary duct closure in terms of postoperative hospital stay and hospitalization cost. It is the prior option for the choledochotomy closure after LCBDE in suitable patients.


Assuntos
Coledocolitíase/terapia , Ducto Colédoco/cirurgia , Drenagem/instrumentação , Feminino , Hospitalização/economia , Humanos , Laparoscopia , Tempo de Internação/estatística & dados numéricos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Complicações Pós-Operatórias , Estudos Retrospectivos , Stents
4.
Ying Yong Sheng Tai Xue Bao ; 27(9): 2884-2890, 2016 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-29732851

RESUMO

Kriging interpolation analysis was conducted with ArcGIS to find out the distribution characteristics of heavy metals concentrations in the surface sediments of the coastal wetland mudflat on the Yalu River estuary, environmental risk index and Hakanson potential ecological risk index were used to assess their extents of pollution in this area.The concentrations of heavy metals in the surface sediments of the study area were at a relatively high level compared with the typical estuarine wetland. The concentration of heavy metals in the east was higher than that in the west, and in the human activity area, the concentration was higher. Cu was found to contribute the most to the pollution status based on environmental risk index method, while Hg and Cd produced the greatest potential ecological harm according to Hankanson Potential ecological risk index method. The average potential ecological risk index (RI) of the Yalu River estuary wetland was 189.30 (ranged from 93.65-507.20), suggesting a moderate ecological risk. However, the potential ecological risk was highest in the east and should be treated as the major heavy metal pollution prevention area in the future.


Assuntos
Monitoramento Ambiental , Estuários , Sedimentos Geológicos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , Cádmio , China , Cobre , Mercúrio , Medição de Risco , Rios , Análise Espacial , Áreas Alagadas
5.
PLoS Comput Biol ; 10(1): e1003442, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24499931

RESUMO

The splicing regulator Polypyrimidine Tract Binding Protein (PTBP1) has four RNA binding domains that each binds a short pyrimidine element, allowing recognition of diverse pyrimidine-rich sequences. This variation makes it difficult to evaluate PTBP1 binding to particular sites based on sequence alone and thus to identify target RNAs. Conversely, transcriptome-wide binding assays such as CLIP identify many in vivo targets, but do not provide a quantitative assessment of binding and are informative only for the cells where the analysis is performed. A general method of predicting PTBP1 binding and possible targets in any cell type is needed. We developed computational models that predict the binding and splicing targets of PTBP1. A Hidden Markov Model (HMM), trained on CLIP-seq data, was used to score probable PTBP1 binding sites. Scores from this model are highly correlated (ρ = -0.9) with experimentally determined dissociation constants. Notably, we find that the protein is not strictly pyrimidine specific, as interspersed Guanosine residues are well tolerated within PTBP1 binding sites. This model identifies many previously unrecognized PTBP1 binding sites, and can score PTBP1 binding across the transcriptome in the absence of CLIP data. Using this model to examine the placement of PTBP1 binding sites in controlling splicing, we trained a multinomial logistic model on sets of PTBP1 regulated and unregulated exons. Applying this model to rank exons across the mouse transcriptome identifies known PTBP1 targets and many new exons that were confirmed as PTBP1-repressed by RT-PCR and RNA-seq after PTBP1 depletion. We find that PTBP1 dependent exons are diverse in structure and do not all fit previous descriptions of the placement of PTBP1 binding sites. Our study uncovers new features of RNA recognition and splicing regulation by PTBP1. This approach can be applied to other multi-RRM domain proteins to assess binding site degeneracy and multifactorial splicing regulation.


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas/química , Proteína de Ligação a Regiões Ricas em Polipirimidinas/química , RNA/química , Algoritmos , Animais , Sítios de Ligação , Biologia Computacional/métodos , Éxons , Guanosina/química , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Humanos , Modelos Logísticos , Cadeias de Markov , Camundongos , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Probabilidade , Ligação Proteica , Estrutura Terciária de Proteína , Pirimidinas/química , Transcriptoma
6.
Chin Med J (Engl) ; 125(20): 3660-4, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23075720

RESUMO

BACKGROUND: Clinical practice guidelines (CPGs) play an important role in healthcare in China as well as in the world. However, the current status and trends of Chinese CPGs are unknown. The aim of this study was to systematically review the present situation and the quality of Chinese CPGs published in the peer-reviewed medical literature. METHODS: To identify Chinese CPGs, a systematic search of relevant literature databases (CBM, WANFANG, VIP, and CNKI) was performed for the period January 1978 to December 2010. We used the AGREE II instrument to assess the quality of the included guidelines. RESULTS: We evaluated 269 guidelines published in 115 medical journals from 1993 to 2010 and produced by 256 different developers. Only four guidelines (1%) described the systematic methods for searching and selecting the evidence, 14 (5%) guidelines indicated an explicit link between the supporting evidence and the recommendations, only one guideline used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. Thirty-one guidelines (12%) mentioned updates and the average frequency of update was 5.5 years; none described a procedure for updating the guideline. From the assessment with the Appraisal of Guidelines for Research and Ecaluation II (AGREE II), the mean scores were low for the domains "scope and purpose" (19%) and "clarity of presentation" (26%) and very low for the other domains ("rigour of development" 7%, "stakeholder involvement" 8%, "applicability" 6% and "editorial independence" 2%). CONCLUSIONS: Compared with other studies on the quality of guidelines assessed with the AGREE instrument in other countries, Chinese CPGs received lower scores, which indicates a relatively poor quality of the guidelines. However, there was some increase over time.


Assuntos
Guias de Prática Clínica como Assunto/normas , China , Humanos , Controle de Qualidade , Fatores de Tempo
7.
Dongwuxue Yanjiu ; 33(5): 493-7, 2012 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-23019031

RESUMO

The purpose of this study was to establish a parabiotic mice model and assess the physiological changes of the mice under the parabiotic state. Thirteen pairs of isogenic partners were studied. The model was created by preparing a bridge of skin and subcutaneous tissues between the two mice starting distal of the elbow joint along the humerus along the lateral costal region until the end of the waist line. Physiological, social and affective qualities of life were studied in the mice through behavioural observations for 120 days following the parabiotic surgery. During the first 2-3 days following the operation, the animals suffered from severe pain and distress. During the following days and weeks, the physiological system began to recover and the animals displayed behavioral adaptations to the parabiotic condition. All animals survived at day 120. At three days post operation, the body weight began to decrease. Following this, the animals experienced a continual body weight recovery and reached pre-surgical measures at about 30 days post op. Forty-eight h post op., faecal corticosterone-metabolites were extremely elevated, but their levels returned to two to four times of levels in control females within 72 hours post op. The faecal corticosterone-metabolite levels decreased near to control values on day 75. Out of the 13 pairs, the blood exchange rate of three parabiotic partners was tested, with the result being normal post op. After 12 weeks, the total blood exchange between both partners needed 63 or 46 or 107 min, respectively. These results demonstrated that the animals could adapt behaviourally to the parabiotic situation. Therefore, this parabiosis mouse model may provide useful insights in many research areas, such as transplantation immunity, hematological system and metabolism, etc.


Assuntos
Camundongos/fisiologia , Modelos Animais , Animais , Peso Corporal , Corticosterona/metabolismo , Feminino , Masculino , Camundongos/cirurgia , Camundongos Endogâmicos C57BL , Parabiose
8.
J Pharm Biomed Anal ; 52(2): 173-80, 2010 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-20122811

RESUMO

This paper describes the first analytical method for the determination of four flavonoids (sutherlandins A-D) and four cycloartanol glycosides (sutherlandiosides A-D) from the aerial parts of Sutherlandia frutescens (L.) R. Br. A separation by HPLC was achieved by using a reversed phase (RP-18) column, PDA with ELS detection, and a water/acetonitrile gradient as the mobile phase. The wavelength used for quantification of four flavonoids with the diode array detector was 260 nm. Owing to their low UV absorption, the cycloartanol glycosides were detected by evaporative light scattering. The method was validated for linearity, repeatability, limits of detection (LOD) and limits of quantification (LOQ). The limits of detection and limits of quantification of eight compounds were found to be in the range from 0.1 to 7.5 microg/mL and 0.5 to 25 microg/mL, respectively. The analysis of products showed considerable variation of 1.099-5.224 mg/average weight for the major compound, sutherlandioside B. The eight compounds in plant sample and products of S. frutescens were further confirmed by LC-ESI-TOF. This method involved the use of the [M+H](+) and [M+Na](+) ions in the positive ion mode with extractive ion monitoring (EIM).


Assuntos
Cromatografia Líquida/métodos , Fabaceae , Flavonoides/análise , Glicosídeos/análise , Componentes Aéreos da Planta/química , Calibragem , Cromatografia de Fase Reversa/métodos , Flavonoides/química , Glicosídeos/química , Glicosídeos/classificação , Luz , Limite de Detecção , Espectrometria de Massas/métodos , Estrutura Molecular , Folhas de Planta/química , Caules de Planta/química , Padrões de Referência , Reprodutibilidade dos Testes , Espalhamento de Radiação , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrofotometria Ultravioleta/métodos
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