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1.
Cont Lens Anterior Eye ; 47(2): 102123, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38246852

RESUMO

OBJECTIVE: To investigate the effects of orthokeratology lenses (OK lenses) on corneal biomechanics in subjects of different ages. METHODS: Fifty subjects with mild to moderate myopia were categorized into three groups (Group I-III) based on their age. Corvis ST was used to collect dynamic corneal response parameters (DCRs) at different follow-up time points. Repeated measures analysis of variance combined with simple effect analysis was used to analyze the changes in DCRs in different groups during the follow-up period. Multiple linear regression analysis was used to analyze the correlations between axial length growth (ALG) at 6 months (ALG-6M) or 12 months (ALG-12M) and sex, baseline spherical equivalent refraction (SER), and DCRs. RESULTS: The DCRs changed in all three groups after wearing OK lenses. Most DCRs showed significant differences between baseline and 6 months after wearing OK lenses, while the differences between DCRs at 6 months and 12 months were not statistically significant. No significant differences in DCRs were observed among the three groups at the same follow-up time point. Additionally, at 6 months post-OK lens wear, ALG-6M was significantly correlated with velocity of the corneal apex at the first applanation (A1V-6M) (P = 0.002), Corvis biomechanical index (CBI-6M) (P = 0.004), the maximum amount of corneal movement (DAM-6M) (P = 0.010), deformation amplitude ratio of 2 mm (DAR2-6M) (P = 0.010), and stress-strain index (SSI-6M) (P = 0.038) in Group I. Furthermore, ALG-12M showed significant correlations with SSI-6M (P = 0.031), peak distance at the DAM (PD)-6M (P = 0.037), baseline Ambrósio Relational Thickness to the horizontal profile (P = 0.013) in Group I. CONCLUSIONS: The majority of DCRs displayed significant changes within the initial 6 months of OK lens wear. Minimal variation in DCRs was observed across different age groups at the same follow-up time point. Certain DCR parameters exhibited correlations with ALG, suggesting their potential in predicting ALG in myopic children undergoing OK lenses correction.


Assuntos
Miopia , Procedimentos Ortoceratológicos , Criança , Humanos , Topografia da Córnea , Córnea , Miopia/terapia , Refração Ocular , China , Comprimento Axial do Olho
2.
Eur Radiol ; 34(1): 579-587, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37528300

RESUMO

OBJECTIVES: This study was aimed to quantitatively assess hyperperfusion using arterial spin labeling (ASL) to predict hemorrhagic transformation (HT) in acute ischemic stroke (AIS) patients. METHODS: This study enrolled 98 AIS patients with anterior circulation large vessel occlusion within 24 h of symptom onset. ASL was performed before mechanical endovascular therapy. On pre-treatment ASL maps, a region with relative cerebral blood flow (CBF) ≥ 1.4 was defined as an area of hyperperfusion. The maximum CBF (CBFmax) of hyperperfusion was calculated for each patient. A non-contrast CT scan was performed during the subacute phase for the evaluation of HT. Good clinical outcome was defined as a 90-day modified Rankin scale score of 0-2. RESULTS: The CBFmax of hyperperfusion (odds ratio, 1.023; 95% confidence interval [CI], 1.005-1.042; p = 0.012) was an independent risk factor for the status of HT. The CBFmax of hyperperfusion for HT showed an area under the curve of 0.735 (95% CI, 0.588-0.882) with optimal cutoff value, sensitivity, and specificity being 146.5 mL/100 g/min, 76.9%, and 69.6%, respectively. There was a statistically significant relationship between HT grades (from no HT to PH2) and CBFmax of hyperperfusion with a Spearman rank correlation of 0.446 (p = 0.001). In addition, low CBFmax of hyperperfusion were associated with good functional outcome (95% CI, 17.130-73.910; p = 0.002). CONCLUSIONS: High CBFmax of hyperperfusion was independently associated with subsequent HT and low CBFmax of hyperperfusion linked to good functional outcome. There was a positive correlation between HT grade and CBFmax. CLINICAL RELEVANCE STATEMENT: Arterial spin labeling is a noninvasive and contrast agent-independent technique, which is sensitive in detecting hyperperfusion. This study shows that the cerebral blood flow of hyperperfusion is associated with clinical prognosis, which will benefit more patients. KEY POINTS: • Quantitative assessment of hyperperfusion using pre-treatment arterial spin labeling to predict hemorrhagic transformation and prognosis in acute ischemic stroke patients. • The maximum cerebral blood flow of hyperperfusion was associated with hemorrhagic transformation and clinical prognosis and higher maximum cerebral blood flow of hyperperfusion was associated with higher grade hemorrhagic transformation. • The maximum cerebral blood flow of hyperperfusion can predict hemorrhagic transformation which enables timely intervention to prevent parenchymal hematoma.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico , AVC Isquêmico/complicações , Marcadores de Spin , Artérias , Circulação Cerebrovascular/fisiologia , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/terapia
3.
Artigo em Inglês | MEDLINE | ID: mdl-30884750

RESUMO

Changes in economic development stage and growth type will lead to variations in the CO2 emissions. Traditional empirical analysis of the variations often only considers the impact of influencing factors on CO2 emissions from a single dimension. Under the background of China's economy transferring from high-speed growth to high-quality development, this paper comprehensively considers the characteristics of the relevant influencing factors under different development stages and growth rates, and further calculates the panel gray incidence degree between CO2 emissions and these influencing factors in eastern, central, and western China. Based on the different development conditions, corresponding benchmarks of the indicators for the three regions (eastern, western, and central China) are accordingly set, highlighting the unity as well as the uniqueness between different regions. Furthermore, this paper verifies the environmental Kuznets curve (EKC) in the three regions. The result shows that all the factors of per capita Gross Domestic Product (GDP), Energy Intensity, Urbanization Level, and Trade Openness have a high correlation with CO2 emissions in the three regions, in which CO2 emissions are all between the two inflection points of the inverted N-shaped model.


Assuntos
Poluentes Atmosféricos/análise , Dióxido de Carbono/análise , Desenvolvimento Econômico , China , Produto Interno Bruto , Modelos Econômicos , Urbanização
4.
Mol Vis ; 24: 143-152, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29430168

RESUMO

Purpose: Adenoid cystic carcinoma (ACC) in the lacrimal gland is a rare malignancy. P16 is encoded by the CDKN2A gene, which is recognized as a tumor suppressor due to its inactivation in many types of tumors. However, p16 overexpression is also linked to adverse tumor parameters. These contradictory observations have also been confirmed in ACCs in the salivary glands. Furthermore, evidence of human papilloma virus (HPV) infection is found in a proportion of ACCs in the salivary glands. P16 is often overexpressed in HPV-related squamous cell carcinoma in parallel. To our knowledge, the role of p16 and HPV in ACCs in the lacrimal gland is still unknown. Methods: Twenty-one ACCs in the lacrimal gland and ten matched healthy lacrimal glands were studied. P16 was detected with immunohistochemistry (IHC), and HPV was detected with in situ hybridization (ISH) and PCR in all cases. Other cell cycle proteins were also detected with IHC, including cyclin D1 and Ki67. The methylation status of the p16 promoter was detected with methylation-specific PCR (MSP) to further investigate the regulation of p16 expression. Results: The expression rates of p16 (47.6%, 10/21), cyclin D1 (100%, 21/21), and Ki67 (52.4%, 11/21) were increased in ACCs compared to healthy lacrimal glands (negative). The results showed p16 expression was limited to the inner ductal epithelial cells in the majority of the tubular and cribriform patterns. In solid ACCs, p16 was uniformly positive. HPV was negative in all 21 cases with ISH and PCR. P16 overexpression was associated with cyclin D1 overexpression (p=0.013). Only 13 cases were tested successfully with MSP. The expression rate of p16 methylation was 23.1% (3/13) of the ACCs. Compared with primary ACCs, recurrent ACCs showed higher p16, cyclin D1, and Ki67 expression (p=0.011, p=0.026, p=0.049, respectively). Conclusions: In summary, p16 overexpression was cell-type dependent in ACCs in the lacrimal gland, while HPV infection was negative. P16 overexpression was unrelated to HPV infection. The mechanism of p16 overexpression needs to be further investigated in ACCs in the lacrimal gland.


Assuntos
Carcinoma Adenoide Cístico/genética , Ciclina D1/genética , Inibidor de Quinase Dependente de Ciclina p18/genética , Neoplasias Oculares/genética , Regulação Neoplásica da Expressão Gênica , Antígeno Ki-67/genética , Adolescente , Adulto , Idoso , Carcinoma Adenoide Cístico/metabolismo , Carcinoma Adenoide Cístico/mortalidade , Carcinoma Adenoide Cístico/patologia , Estudos de Casos e Controles , Ciclina D1/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p18/metabolismo , Neoplasias Oculares/metabolismo , Neoplasias Oculares/mortalidade , Neoplasias Oculares/patologia , Feminino , Humanos , Antígeno Ki-67/metabolismo , Aparelho Lacrimal/metabolismo , Aparelho Lacrimal/patologia , Masculino , Pessoa de Meia-Idade , Papillomaviridae , Infecções por Papillomavirus , Análise de Sobrevida
5.
Artigo em Inglês | MEDLINE | ID: mdl-29236083

RESUMO

The non-linear relationship between provincial economic growth and carbon emissions is investigated by using panel smooth transition regression (PSTR) models. The research indicates that, on the condition of separately taking Gross Domestic Product per capita (GDPpc), energy structure (Es), and urbanisation level (Ul) as transition variables, three models all reject the null hypothesis of a linear relationship, i.e., a non-linear relationship exists. The results show that the three models all contain only one transition function but different numbers of location parameters. The model taking GDPpc as the transition variable has two location parameters, while the other two models separately considering Es and Ul as the transition variables both contain one location parameter. The three models applied in the study all favourably describe the non-linear relationship between economic growth and CO2 emissions in China. It also can be seen that the conversion rate of the influence of Ul on per capita CO2 emissions is significantly higher than those of GDPpc and Es on per capita CO2 emissions.


Assuntos
Poluentes Atmosféricos/análise , Dióxido de Carbono/análise , Desenvolvimento Econômico , Monitoramento Ambiental , China , Modelos Econômicos , Modelos Teóricos
6.
Ying Yong Sheng Tai Xue Bao ; 24(3): 705-12, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23755484

RESUMO

Based on the remote sensing data in 2000, 2005, and 2010, this paper analyzed the variation trends of the land use type and landscape pattern in Daiyue District of Tai' an City from 2000 to 2010. The ecological risk index was built, that of the District was re-sampled and spatially interpolated, and the spatiotemporal pattern of the ecological risk in the rural-urban ecotone of the District was analyzed. In 2000-2010, the main variation trend of the land use type in the District was the shift from natural landscape to artificial landscape. The intensity of human disturbance was larger in cultivated land, garden plot, and forestland than in other landscape types, while the human disturbance in water area was smaller. The ecological loss degree of cultivated land and water area decreased somewhat, while that of the other land use types presented an increasing trend. The ecological risk distribution in the District was discrete in 2000 and 2010, but most centralized in 2005. The ecological risk of each ecological risk sub-area had an increasing trend in 2000-2005, but was in adverse in 2005-2010. In 2000-2010, the ecological risk of the District was mainly at medium level. Spatially, the distribution of the ecological risk in the District had an obvious differentiation, with an overall diffusive increasing from forestland as the center to the surrounding areas. In the District, the ecological risk was mainly at medium and higher levels, the area with lower ecological risk had an obvious dynamic change, while that with the lowest and highest ecological risk had less change.


Assuntos
Ecossistema , Atividades Humanas/estatística & dados numéricos , Urbanização , China , Cidades , Produtos Agrícolas/crescimento & desenvolvimento , Ecologia/métodos , Tecnologia de Sensoriamento Remoto , Medição de Risco , População Rural , Análise Espaço-Temporal , População Urbana
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