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1.
Inorg Chem ; 63(26): 12350-12359, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38887050

RESUMEN

Hybrid metal halide materials with charming phase transition behaviors have attracted considerable attention. In former works, much attention has been focused on the phase transition triggered by the order-disorder or displacement motions of the organic component. However, manipulating the variation of the inorganic component to achieve the phase transition has rarely been reported. Herein, two novel organic-inorganic hybrid materials, [THPM]n[AgX2]n (THPM = 3,4,5,6-tetrahydropyrimidin-1-ium, X = I for 1 and Br for 2) with the [AgX2]nn- anionic chain structure, were synthesized. At 293 K, the [AgX2]nn- chains in 1 were constructed by the tetramer units of Ag atoms, while that in 2 was assembled by the dimer structure. Upon heating to 355 K, owing to the variation of the metallophilic interaction between adjacent Ag atoms, a unique transformation process from tetramer to dimer in [AgI2]nn- chains of 1 can be detected and endow 1 with a giant anisotropic thermal expansion with linear strain of ∼7% and shear strain of ∼20%, which can be used as a mechanical actuator for switching. Alternatively, for 2, no phase transition process can be observed upon the temperature variation. This work provides an effective approach to design phase transition materials triggered by the inorganic part.

2.
J Obstet Gynaecol ; 42(5): 1467-1473, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34927543

RESUMEN

The purpose of this study was to evaluate the predictive value of ultrasound markers measured at different time points of the controlled ovarian hyperstimulation (COH) cycle on ovarian response and outcome indicators in the IVF-ET cycle. According to the oestrogen level and the number of retrieved oocytes, patients who planned for COH treatment were separated into low-response group, normal and high-response group. The ovarian stromal artery flow parameters on the day of pituitary down-regulation, day 1, day 7, day 10, and the day of hCG injection were collected prospectively. We also have collected the data of cumulus oophorus count on the day of hCG injection by transvaginal sonography. Compared with the low-response group, on the first day of the COH cycle PI, RI, and S/D were lower in the high-response group than they were in the low-response group (p < .05). PSV and EDV were significantly higher in the high-response group than they were in the low-response group (p < .01), and the PSV on the first day of the COH cycle have statistical significance in predicting the number of high-quality embryos. The number of cumulus oophorus on the day of hCG injection has statistical significance in predicting the number of oocytes retrieved and fertilised oocytes. We conclude that the ovarian stromal artery flow parameters on the first day of the COH cycle and cumulus oophorus count on hCG injection day can serve as efficient indicators for an early assessment of ovarian response and individualised ovulation induction.IMPACT STATEMENTWhat is already known on this subject? AMH, AFC, and the age of the patient are well-known effective parameters for the evaluation of ovarian response, but these are insufficient and full of individual differences. Some researchers have investigated the value of colour Doppler ultrasound and cumulus oophorus in assessing ovarian response, but no definitive conclusion has been reached.What do the results of this study add? The hemodynamic parameters of ovarian stromal artery on the first day of the COH cycle and the number of cumulus oophorus on the day of hCG injection detected by Transvaginal Colour Doppler Sonography (TV-CDS) could be used to predict the ovarian response.What are the implications of these findings for clinical practice and/or further research? Ovarian stromal artery flow parameters and cumulus oophorus detected by TV-CDS can potentially be offered as a complementary parameter for ovarian reserve.


Asunto(s)
Síndrome de Hiperestimulación Ovárica , Reserva Ovárica , Femenino , Fertilización In Vitro/métodos , Humanos , Inducción de la Ovulación/métodos
3.
Dalton Trans ; 51(21): 8491-8496, 2022 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-35605983

RESUMEN

In this work, we report two supramolecular isomorphic dodecanuclear cobalt complexes, [Co12(mtz)3(L)6(NO3)2(OH)(N3)3]·(OH)3 (1) and [Co12(mtz)3(L)6(NO3)2(OH)(N3)(OAc)]·(OH)4 (2), (Hmtz = 5-methyl-1H-tetrazole, H2L = 7,7'-(ethane-1,1-diyl) diquinolin-8-ol) crystallizing in the P̄ space group with the same unit cell parameters. In 1 and 2, two pirate hat-like hexanuclear Co6(NO3)(L)3 units form the same dodecanuclear metal shell, but the ligands between the hexanuclear units as the core are distinct. The introduction of acetate anions leads to a blue shift of the absorption band in the visible region. Magnetism studies indicate an antiferromagnetic interaction between the CoII ions in the clusters.


Asunto(s)
Cobalto , Metales , Iones , Ligandos , Magnetismo
4.
Huan Jing Ke Xue ; 41(3): 1217-1226, 2020 Mar 08.
Artículo en Zh | MEDLINE | ID: mdl-32608623

RESUMEN

Chromophoric dissolved organic matter (CDOM) optical absorption characteristics, CDOM spectral slopes (S275-295), contribution of each component to water absorption, and the effects of environmental factors on them were analyzed to determine the sources and composition of CDOM in high-turbidity waters on the Loess Plateau. Samples in rivers and lakes (saline and freshwater) in the Loess Plateau area of Shaanxi and Inner Mongolia were collected in May 2018. The results demonstrated significant differences in CDOM absorption optical characteristics between rivers and lakes. The average aCDOM(440) (CDOM concentration, 8.45 m-1) in lakes was higher than that of rivers (2.70 m-1), and the saline lakes showed a higher CDOM concentration (13.52 m-1) than the freshwater lakes (3.38 m-1). Moreover, the light utilization efficiency of freshwater lakes is higher than that of saline lakes and turbid rivers. Great differences in pH and dissolved organic carbon (DOC) were observed between different types of water (P<0.01). The differences in electrical conductivity (EC), turbidity (Tur), and total suspended matter concentration (TSM) were significant with no statistical significances (P>0.1). The chlorophyll a concentration (Chla) in saline lakes was close to the Chla concentration in freshwater lakes if extreme values were excluded. In addition, the CDOM molecular weights of lake water were lower than those in the rivers, while CDOM molecular weights in saline lakes were lower than those in freshwater lakes based on the S275-295. Analyses of specific ultraviolet absorbance (SUVA254) were also conducted to determine the sources of CDOM in different water types, and the results showed that the more terrigenous humus were brought into the rivers and saline lakes compared with the freshwater lakes. Redundancy analysis (RDA) indicated that river and lake water quality parameters of the cumulative variance explained rates were 35.2% for river samples and 61.4% for lake samples, and 100% for samples in the saline and freshwater lakes individually. The results of RDA showed that dissolved oxygen (DO), water temperature, and EC exerted significant effects on CDOM optical properties of the river (P<0.01), while DOC, TSM, and Tur had a great influence on the CDOM optical properties of lakes (P<0.01). There was a strong correlation between pH and CDOM in the saline lakes, while DOC was significantly correlated with CDOM in the freshwater lakes (P<0.05).

5.
World J Clin Cases ; 8(21): 5389-5393, 2020 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-33269274

RESUMEN

BACKGROUND: Conjoined twins are a rare occurrence, and the majority of these malformations are detected during second trimester screening. CASE SUMMARY: Herein we report a case of conjoined twins, which was diagnosed by ultrasound at 8 wk gestation and was normal at 7 wk gestation. The two fetuses shared one heart and were diagnosed as thoracopagus twins. This is the first report of conjoined twins diagnosed at 8 wk gestation. The pregnancy was terminated electively at 9 wk gestation. Because some congenital malformations can be diagnosed earlier, a prenatal ultrasound examination at an early gestational stage cannot be dismissed. CONCLUSION: This case demonstrates that a 7-8 wk gestation might be the earliest period when conjoined twins can be diagnosed by ultrasound.

6.
Chin Med J (Engl) ; 132(16): 1974-1982, 2019 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-31348028

RESUMEN

OBJECTIVE: Ultrasound imaging is well known to play an important role in the detection of thyroid disease, but the management of thyroid ultrasound remains inconsistent. Both standardized diagnostic criteria and new ultrasound technologies are essential for improving the accuracy of thyroid ultrasound. This study reviewed the global guidelines of thyroid ultrasound and analyzed their common characteristics for basic clinical screening. Advances in the application of a combination of thyroid ultrasound and artificial intelligence (AI) were also presented. DATA SOURCES: An extensive search of the PubMed database was undertaken, focusing on research published after 2001 with keywords including thyroid ultrasound, guideline, AI, segmentation, image classification, and deep learning. STUDY SELECTION: Several types of articles, including original studies and literature reviews, were identified and reviewed to summarize the importance of standardization and new technology in thyroid ultrasound diagnosis. RESULTS: Ultrasound has become an important diagnostic technique in thyroid nodules. Both standardized diagnostic criteria and new ultrasound technologies are essential for improving the accuracy of thyroid ultrasound. In the standardization, since there are no global consensus exists, common characteristics such as a multi-feature diagnosis, the performance of lymph nodes, explicit indications of fine needle aspiration, and the diagnosis of special populations should be focused on. Besides, evidence suggests that AI technique has a good effect on the unavoidable limitations of traditional ultrasound, and the combination of diagnostic criteria and AI may lead to a great promotion in thyroid diagnosis. CONCLUSION: Standardization and development of novel techniques are key factors to improving thyroid ultrasound, and both should be considered in normal clinical use.


Asunto(s)
Inteligencia Artificial , Glándula Tiroides/diagnóstico por imagen , Aprendizaje Profundo , Humanos , Nódulo Tiroideo/diagnóstico por imagen
7.
Quant Imaging Med Surg ; 8(5): 535-546, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30050788

RESUMEN

Lung diseases in neonates can be life-threatening condition and may result in respiratory failure and death. Chest X-ray is a traditional diagnostic technique that results in radiation exposure to patients. Lung ultrasound is a user-friendly imaging technique that has been increasingly used in clinical practice in recent years and presents the advantages of real-time imaging and without radiation. Here we review the sonographic appearances of common neonatal lung diseases and present demonstration of typical cases.

8.
Chin J Integr Med ; 23(12): 929-936, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28523535

RESUMEN

OBJECTIVE: To find the signaling pathway of triptolide (TP)-induced liver injury and to reveal whether NF-E2-related factor 2 (Nrf2) plays an important role in cellular self-protection. METHODS: The L-02 and HepG2 cells were cultured and treated with various concentrations of TP. The cell viability was observed, and the cell medium was collected for detecting the aspartate aminotransferase (ALT), alanine aminotransferase (AST), lactate dehydrogenase (LDH), superoxide dismutase (SOD) and L-glutathione production (GSH) levels. Nrf2 and its downstream target NAD(P)H: quinine oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1) expression, the nuclear translocation of Nrf2, and the binding ability of Nrf2 and antioxidant response element (ARE) were also identified. Meanwhile, shRNA was used to silence Nrf2 in L-02 cells to find out whether Nrf2 plays a protective role. RESULTS: The viability of the L-02 and HepG2 cells treated with TP decreased in a doseand time-dependent manner, and TP (20-80 µg/mL) markedly induced the release of ALT, AST and LDH (P<0.05 or P<0.01), reduced the levels of SOD and GSH (P<0.01), and increased the intracellular reactive oxygen species. Meanwhile, TP augmented the Nrf2 expression in L-02 and HepG2 cells (P<0.05 or P<0.01), induced Nrf2 nuclear translocation, increased the Nrf2 ARE binding activity, and increased HO-1 and NQO1 expressions. Nrf2 knockdown revealed a more severe toxic effect of TP (P<0.05 or P<0.01). CONCLUSIONS: Human hepatic cells treated with TP induced oxidative stress, and led to cytotoxicity. Self-protection against TP-induced toxicity in human hepatic cells might be via Nrf2-ARE-NQO1 transcriptional pathway.


Asunto(s)
Citoprotección/efectos de los fármacos , Diterpenos/toxicidad , Hepatocitos/metabolismo , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Fenantrenos/toxicidad , Transducción de Señal/efectos de los fármacos , Elementos de Respuesta Antioxidante/genética , Muerte Celular/efectos de los fármacos , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Compuestos Epoxi/toxicidad , Técnicas de Silenciamiento del Gen , Hemo-Oxigenasa 1/metabolismo , Células Hep G2 , Hepatocitos/efectos de los fármacos , Humanos , Estrés Oxidativo/efectos de los fármacos , ARN Interferente Pequeño/metabolismo
10.
Complement Ther Med ; 23(2): 283-97, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25847567

RESUMEN

OBJECTIVE: To evaluate the effectiveness and safety of the Chinese herbal medicine for kidney nourishment (CHMK) assessed with the Mini-Mental Status Examination (MMSE) index objective outcome measures in individuals with Alzheimer's disease. METHODS: Searches were conducted in 7 medical databases from their inceptions until July 19, 2014 for randomized controlled trials (RCTs) that compared the oral administration of CHMK plus conventional pharmacotherapy with the same conventional pharmacotherapy alone with MMSE index measures as outcomes. Relevant resources were also manually retrieved. Two reviewers screened the citations of the reports, assessed the risk of bias and extracted data independently. Data analysis was carried out with Cochrane Collaboration's RevMan5.2.6 software and evidence quality grading evaluation of the systematic review was conducted with Grades of Recommendations Assessment Development and Evaluation (GRADE) profiler software. RESULTS: A total of 20 studies involving 1682 participants were included in the meta-analysis. There were 15 trials that compared CHMK with conventional pharmacotherapy and 5 trials that compared CHMK plus conventional pharmacotherapy with conventional pharmacotherapy alone. The main meta-analysis results showed relative benefits in effective rates in five studies (odds ratio [OR] 2.74, 95% confidence interval [CI] 1.55-4.85) and cure rate/clinical-control rates in five studies (OR 1.91, 95% CI 1.27-2.88) in favor of the CHMK plus conventional pharmacotherapy group. As for CHMK compared with conventional pharmacotherapy, no significant differences were noted in the effective rate (OR 1.09, 95% CI 0.82-1.46; cure rate (OR 1.06, 95% CI 0.81-1.38) and detailed sub-group of MMSE scores from the onset time to 4 weeks (weighted mean difference [WMD] 0.31, 95% confidence interval [CI] -0.81 to 1.42, 8 weeks WMD 1.12, 95% CI -0.54 to 2.78, 12 weeks (WMD 0.43, 95% CI -1.62 to 2.48, or 24 weeks WMD 1.92, 95% CI -1.60 to 5.44) follow-up and the overall effect (WMD 0.79, 95% CI -0.11 to 1.69). Moreover, weaknesses in methodological quality were identified in most studies according to Cochrane Risk of Bias tool assessment, while the quality level of GRADE classification indicated "very low". The incidence of adverse events with CHMK (0.87%) was lower than in the conventional pharmacotherapy group (4.08%), which revealed use of CHMK was relatively safer than conventional pharmacotherapy alone. CONCLUSION: The effectiveness and safety of oral administration of CHMK cannot be currently determined because of publication bias and the low quality level of the included trials. Further studies on a larger scale and with more rigorous designs are required to define the role of CHMK in the treatment of AD.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Medicamentos Herbarios Chinos/administración & dosificación , Administración Oral , Sesgo , Medicamentos Herbarios Chinos/efectos adversos , Humanos
11.
Curr Pharm Des ; 19(35): 6353-66, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23469998

RESUMEN

Exposure of human skin to nanoparticles (NPs) is increasing with the development of nanotechnology and new applications of NPs in medicine. Safety concerns have sparked debate on the capacity of NPs to penetrate through skin and enter into the body. This article attempts to summarize the recent evidence on whether NPs penetrate human skin and the factors that may affect the penetration. Skin structure and penetration mechanisms are reviewed to provide background information. Size, shape, formulation, surface properties and application methods and their effects on skin penetration are specifically discussed. Finally, the relationship between skin penetration and nanotoxicity is reviewed to further emphasise the importance of the research in this area.


Asunto(s)
Sistemas de Liberación de Medicamentos , Nanopartículas , Absorción Cutánea , Animales , Humanos , Nanopartículas/efectos adversos , Nanotecnología/métodos , Tamaño de la Partícula , Permeabilidad , Piel/metabolismo , Propiedades de Superficie
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