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Background: Computed tomography-derived fractional flow reserve (CT-FFR) is a non-invasive imagological examination used for diagnosing suspected coronary atherosclerotic heart disease, providing the morphological and functional value on a three-dimensional (3D) coronary artery model. This article aimed to collate the existing knowledge and predict this novel technology's future research hotspots. Methods: To collect data, 1,712 articles were retrieved from the Web of Science Core Collection (WoSCC) database from 2012-2022. CiteSpace5.8.R3 was used to visually analyze the research status and predict future research hotspots. Results: Firstly, the United States, China, and the Netherlands were identified as the countries having published the most articles about CT-FFR. Jonathan Leipsic's group ranked first for the highest number of published articles. Secondly, the visualized analysis indicated that the exploration of CT-FFR is multi-disciplinary and involves cardiology, radiology, engineering, and computer science. Thirdly, the hotspots in this field, which were inferred from the keyword distribution and clustering, included the following: "diagnostic performance", "accuracy", and the "prognostic value" of CT-FFR, and comparison of CT-FFR and other imaging methods sharing similarities. The research frontiers included technologies utilized to obtain more accurate CT-FFR values, such as artificial intelligence (AI) and deep learning. Conclusions: As the first visualized bibliometric analysis on CT-FFR, this study captured the current accumulated information in this field and offer more insight and guidance for future research.
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BACKGROUND: Bioresorbable scaffolds (BVS) provide a transient supporting force for blocked vessels and allow them to return to previous physiological characteristics. After verification with twists and turns, it has been acknowledged as an emerging revolution in percutaneous coronary intervention that expresses the current concept of intervention without placement. Through this bibliometric study, we organized the knowledge structure of bioresorbable scaffolds and attempted to predict future research hotspots in this field. METHODS: seven thousand sixty-three articles were retrieved from the web of science core collection database from 2000 to 2022. Then, we utilize CiteSpace 6.1.R2, Biblioshiny and VOS viewer 1.6.18 to analyze the data visually. RESULTS: First, according to the spatial analysis, the number of annual publications has shown an approximately increasing trend over the past 2 decades. The USA, the People's Republic of China, and GERMANY published the most articles on bioresorbable scaffolds. Second, SERRUYS P ranked first for his most prolific work and highest cited frequency in this domain. Third, the hotspots in this field can be inferred from the keyword distribution; they were the fabrication technique based on tissue engineering; the factors to be optimized for bioresorbable scaffolds, such as mechanical property, degradation, and implantation; and the common adverse effects of bioresorbable scaffolds, such as thrombosis. Most importantly, in terms of burst detection, we could speculate that cutting-edge technology for manufacturing scaffolds represented by 3D printing constitutes the future hotspots in bioresorbable scaffold development. CONCLUSION: In the first visualized bibliometric analysis of BVS, we attempt to provide a panoramic view. By enrolling extensive literature, we review the growing trend of BVSs. Since its first introduction, it has been through periods of early prosperity, questioned safety subsequently and the resultantly advanced techniques in recent years. In future, the research should focus on utilizing novel techniques to consummate the manufacturing quality and assure the safety of BVSs.
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Stents Liberadores de Fármacos , Trombosis , Humanos , Implantes Absorbibles , Andamios del Tejido , Stents Liberadores de Fármacos/efectos adversos , Trombosis/etiología , Impresión TridimensionalRESUMEN
OBJECTIVE: To determine whether tumor shear stiffness, as measured by magnetic resonance elastography, corresponds with intratumoral consistency and histotype. MATERIALS AND METHODS: A total of 88 patients with 89 meningiomas (grade 1, 74 typical [13 fibroblastic, 61 non-fibroblastic]; grade 2, 12 atypical; grade 3, 3 anaplastic) were prospectively studied, each undergoing preoperative MRE in conjunction with T1-, T2- and diffusion-weighted imaging. Contrast-enhanced T1-weighted sequences were also obtained. Tumor consistency was evaluated as heterogeneous or homogenous, and graded on a 5-point scale intraoperatively. MRE-determined shear stiffness was associated with tumor consistency by surgeon's evaluation and whole-slide histologic analyses. RESULTS: Mean tumor stiffness overall was 3.81+/-1.74 kPa (range, 1.57-12.60 kPa), correlating well with intraoperative scoring (r = 0.748; p = 0.001). MRE performed well as a gauge of tumor consistency (AUC = 0.879, 95 % CI: 0.792-0.938) and heterogeneity (AUC = 0.773, 95 % CI: 0.618-0.813), significantly surpassing conventional MR techniques (DeLong test, all p < 0.001 after Bonferroni adjustment). Shear stiffness was independently correlated with both fibrous content (partial correlation coefficient = 0.752; p < 0.001) and tumor cellularity (partial correlation coefficient = 0.547; p < 0.001). MRE outperformed other imaging techniques in distinguishing fibroblastic meningiomas from other histotypes (AUC = 0.835 vs 0.513 â¼ 0.634; all p < 0.05), but showed limited ability to differentiate atypical or anaplastic meningiomas from typical meningiomas (AUC = 0.723 vs 0.616 â¼ 0.775; all p > 0.05). Small (<2.5 cm, n = 6) and intraventricular (n = 2) tumors displayed inconsistencies between MRE and surgeon's evaluation. CONCLUSIONS: The results of this prospective study provide substantial evidence that preoperative evaluation of meningiomas with MRE can reliably characterize tumor stiffness and spatial heterogeneity to aid neurosurgical planning.
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Diagnóstico por Imagen de Elasticidad , Neoplasias Meníngeas , Meningioma , Humanos , Diagnóstico por Imagen de Elasticidad/métodos , Estudios Prospectivos , Imagen por Resonancia Magnética/métodos , Meningioma/diagnóstico por imagen , Meningioma/cirugía , Meningioma/patología , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/cirugía , Neoplasias Meníngeas/patologíaRESUMEN
It's a challenge for detecting the therapeutic targets of a polypharmacological drug from variations in the responsed networks in the differentiated populations with complex diseases, as stable coronary heart disease. Here, in an adaptive, 31-center, randomized, double-blind trial involving 920 patients with moderate symptomatic stable angina treated by 14-day Danhong injection(DHI), a kind of polypharmacological drug with high quality control, or placebo (0.9% saline), with 76-day following-up, we firstly confirmed that DHI could increase the proportion of patients with clinically significant changes on angina-frequency assessed by Seattle Angina Questionnaire (ΔSAQ-AF ≥ 20) (12.78% at Day 30, 95% confidence interval [CI] 5.86-19.71%, P = 0.0003, 13.82% at Day 60, 95% CI 6.82-20.82%, P = 0.0001 and 8.95% at Day 90, 95% CI 2.06-15.85%, P = 0.01). We also found that there were no significant differences in new-onset major vascular events (P = 0.8502) and serious adverse events (P = 0.9105) between DHI and placebo. After performing the RNA sequencing in 62 selected patients, we developed a systemic modular approach to identify differentially expressed modules (DEMs) of DHI with the Zsummary value less than 0 compared with the control group, calculated by weighted gene co-expression network analysis (WGCNA), and sketched out the basic framework on a modular map with 25 functional modules targeted by DHI. Furthermore, the effective therapeutic module (ETM), defined as the highest correlation value with the phenotype alteration (ΔSAQ-AF, the change in SAQ-AF at Day 30 from baseline) calculated by WGCNA, was identified in the population with the best effect (ΔSAQ-AF ≥ 40), which is related to anticoagulation and regulation of cholesterol metabolism. We assessed the modular flexibility of this ETM using the global topological D value based on Euclidean distance, which is correlated with phenotype alteration (r2: 0.8204, P = 0.019) by linear regression. Our study identified the anti-angina therapeutic module in the effective population treated by the multi-target drug. Modular methods facilitate the discovery of network pharmacological mechanisms and the advancement of precision medicine. (ClinicalTrials.gov identifier: NCT01681316).
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Angina Estable/tratamiento farmacológico , Fármacos Cardiovasculares/administración & dosificación , Medicamentos Herbarios Chinos/administración & dosificación , Adolescente , Adulto , Anciano , Angina Estable/genética , Angina Estable/patología , Método Doble Ciego , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Inyecciones , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto JovenRESUMEN
OBJECTIVE: To explore the clinical features of thyroid-associated ophthalmopathy (TAO) with extraocular muscle involvement. METHODS: The data of 2170 TAO patients who were seen at the Orbital Disease Clinic, West China Hospital, Sichuan University from September, 2009 to January, 2020 were collected retrospectively. The extraocular muscle involvement of these patients was confirmed by CT or MRI. Their general condition, medical history, clinical manifestations and imaging features were analyzed retrospectively. RESULTS: Among the 2170 TAO patients, 932 were male and 1238 were female. The mean (± SD) age of all the patients was (46.95±13.06) years, ranging between 6 and 85. 1684 patients (77.60%) suffered from hyperthyroidism, 13 patients (0.59%) had thyroid cancer, 80 patients (3.69%) had hypothyroidism, and 393 patients (18.11%) had normal thyroid function. Proptosis (55.25%) and diplopia (33.09%) were the main reasons for their visits to the clinic, and restricted eye movements (83.46%) was the most common sign. 122 patients with a mean age of (53.24±13.07) years did not show any eyelid sign and had only extraocular muscle involvement. The 2170 TAO patients had a total of 3799 eyes of extrocular muscle involvement, with 541 patients experiencing monocular involvement and 1629 patients, binocular involvement; 1204 eyes (31.69%) had a single extrocular muscle involved and 2595 eyes (68.31%) had multiple extrocular muscles involved. Inferior rectus was the most commonly involved muscle, followed by superior rectus, medial rectus, and lateral rectus in descending order of involvement frequency. Of the 1014 patients who underwent enhanced MRI, 71.99% were shown to be in the active phase. 69.03% of the 775 patients identified as being in inactive phase according to their clinical activity score (CAS) were shown to be in the active phase according to their MRI results. CONCLUSION: TAO patients with extraocular muscle involvement have their own specific clinical manifestations. CT and MRI can both be used to assist in the diagnosis of extraocular muscle involvement. MRI can be used to assess the pathological stage of extraocular muscles and is more sensitive than CAS.
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Oftalmopatía de Graves , Adulto , Anciano , China , Femenino , Oftalmopatía de Graves/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Músculos Oculomotores/diagnóstico por imagen , Estudios RetrospectivosRESUMEN
AIMS: Facial features were associated with increased risk of coronary artery disease (CAD). We developed and validated a deep learning algorithm for detecting CAD based on facial photos. METHODS AND RESULTS: We conducted a multicentre cross-sectional study of patients undergoing coronary angiography or computed tomography angiography at nine Chinese sites to train and validate a deep convolutional neural network for the detection of CAD (at least one ≥50% stenosis) from patient facial photos. Between July 2017 and March 2019, 5796 patients from eight sites were consecutively enrolled and randomly divided into training (90%, n = 5216) and validation (10%, n = 580) groups for algorithm development. Between April 2019 and July 2019, 1013 patients from nine sites were enrolled in test group for algorithm test. Sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) were calculated using radiologist diagnosis as the reference standard. Using an operating cut point with high sensitivity, the CAD detection algorithm had sensitivity of 0.80 and specificity of 0.54 in the test group; the AUC was 0.730 (95% confidence interval, 0.699-0.761). The AUC for the algorithm was higher than that for the Diamond-Forrester model (0.730 vs. 0.623, P < 0.001) and the CAD consortium clinical score (0.730 vs. 0.652, P < 0.001). CONCLUSION: Our results suggested that a deep learning algorithm based on facial photos can assist in CAD detection in this Chinese cohort. This technique may hold promise for pre-test CAD probability assessment in outpatient clinics or CAD screening in community. Further studies to develop a clinical available tool are warranted.
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Enfermedad de la Arteria Coronaria , Estenosis Coronaria , Aprendizaje Profundo , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estenosis Coronaria/diagnóstico por imagen , Estudios Transversales , Estudios de Factibilidad , Humanos , Valor Predictivo de las PruebasRESUMEN
A visualization and quantification image analysis method is developed to evaluate the water-absorbing characteristics of rice. A projected image of soaked rice was obtained by a scanner in real time, the expansion ratio of the soaked rice in the projected image was calculated with computer software, and the change in the internal structure was analyzed. The results showed that water absorption had a positive correlation with expansion and the cracks occurred in the internal structure of rice could accelerate the water absorption. The maximum expansion ratio of Japonica rice gradually increased with increased milling time, but that of Japonica glutinous rice was not significantly different (P > 0.05). A high soaking temperature shortened the time to reach the maximum expansion ratio and resulted in a lower expansion ratio in the Indica and Indica glutinous rice but had no significant effect (P > 0.05) in the Japonica and Japonica glutinous rice.
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Visualización de Datos , Análisis de los Alimentos/métodos , Oryza/química , Semillas/química , Agua/química , Adsorción , Análisis de los Alimentos/instrumentación , Genotipo , Oryza/genética , Programas Informáticos , TemperaturaRESUMEN
At present, the treatment of heart failure has entered the plateau phase, and it is necessary to thoroughly study the pathogenesis of heart failure and find out the corresponding treatment methods. Myocardial mitochondria is the main site of cardiac energy metabolism, whose dysfunction is an important factor leading to cardiac dysfunction and heart failure. Mitochondria are highly dynamic organelles. Continuous biogenesis, fusion, fission and mitophagy, contribute to the balance of mitochondria's morphology, quantity, and quality, which is called mitochondrial quality control. Mitochondrial quality control is the cornerstone of normal mitochondrial function and is found to play an important role in the pathological process of heart failure. Here, we provide an overview of the mechanisms of mitochondrial quality control and recent studies on mitochondrial quality control in heart failure, hoping to provide new ideas for drug development in heart failure.
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A phosphine-catalyzed regiospecific (3 + 2) cyclization of 3-nitroindoles with allene esters has been established, which constructed indole-fused five-membered rings in good yields (up to 86%). This reaction serves as a powerful method for the construction of indole-fused five-membered rings. In addition, this reaction provides a useful strategy toward settling the challenge of utilizing other 1,3-dipoles or 1,3-dipole surrogates to perform (3 + 2) cyclizations with 3-nitroindoles in different catalytic modes, which will enrich the chemistry of nitroindoles and catalytic asymmetric dearomatization cyclizations.
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AIMS: Clinical trials have shown the beneficial effects of exercise training against pulmonary fibrosis. This study aimed to investigate whether prophylactic intervention with exercise training attenuates lung fibrosis via modulating endogenous hydrogen sulphde (H2 S) generation. METHODS: First, ICR mice were allocated to Control, Bleomycin, Exercise, and Bleomycin + Exercise groups. Treadmill exercise began on day 1 and continued for 4 weeks. A single intratracheal dose of bleomycin (3 mg/kg) was administered on day 15. Second, ICR mice were allocated to Control, Bleomycin, H2 S, and Bleomycin + H2 S groups. H2 S donor NaHS (28 µmol/kg) was intraperitoneally injected once daily for 2 weeks. RESULTS: Bleomycin-treated mice exhibited increased levels of collagen deposition, hydroxyproline, collagen I, transforming growth factor (TGF)-ß1, Smad2/Smad3/low-density lipoprotein receptor-related proteins (LRP-6)/glycogen synthase kinase-3ß (GSK-3ß) phosphorylation, and Smad4/ß-catenin expression in lung tissues (P < 0.01), which was alleviated by exercise training (P < 0.01 except for Smad4 and phosphorylated GSK-3ß: P < 0.05). Bleomycin-induced lung fibrosis was associated with increased α smooth muscle actin (α-SMA) and decreased E-cadherin expression (P < 0.01). Double immunofluorescence staining showed the co-localization of E-cadherin/α-SMA, indicating epithelial-mesenchymal transition (EMT) formation, which was ameliorated by exercise training. Moreover, exercise training restored bleomycin-induced downregulation of cystathionine-ß-synthase (CBS) and cystathionine-γ-lyase (CSE) expression, as well as H2 S generation in lung tissue (P < 0.01). NaHS treatment attenuated bleomycin-induced TGF-ß1 production, activation of LRP-6/ß-catenin signalling, EMT and lung fibrosis (P < 0.01 except for ß-catenin: P < 0.05). CONCLUSION: Exercise training restores bleomycin-induced downregulation of pulmonary CBS/CSE expression, thus contributing to the increased H2 S generation and suppression of TGF-ß1/Smad and LRP-6/ß-catenin signalling pathways, EMT and lung fibrosis.
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Transición Epitelial-Mesenquimal , Condicionamiento Físico Animal , Fibrosis Pulmonar/prevención & control , Sulfitos/metabolismo , Animales , Bleomicina , Proteína-6 Relacionada a Receptor de Lipoproteína de Baja Densidad/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/metabolismo , Fibrosis Pulmonar/patología , Transducción de Señal , Factor de Crecimiento Transformador beta1/metabolismo , beta Catenina/metabolismoRESUMEN
The surface plasmon polaritons (SPPs) have many potential application due to their local field enhancement and sub-wavelength characteristics. Recently, the gradient metasurface is introduced to couple the spoof SPPs in microwave frequency band. One of the most important issue which should be solved is the narrowband of spoof SPPs coupling on the gradient metasurface. Here, the metasurface is proposed to achieve the wideband helicity dependent directional spoof SPPs coupling for circular polarized light. Our research show that the coupling frequency of spoof SPPs on the gradient metasurface is determined by the dispersion of the metasurface, so the coupling frequency can be controlled by dispersion design. The careful design of each cell geometric parameters has provided many appropriate dispersion relations possessed by just one metasurface. The wave vector matching between the propagating wave and the spoof SPPs has been achieved at several frequencies for certain wave vector provided by the metasurface, which leads to wideband spoof SPPs coupling. This work has shown that wideband helicity dependent directional spoof SPPs coupling has been achieved with a high efficiency. Hence, the proposed wideband spoof SPPs coupling presents the improvement in practice applications.
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Qili qiangxin (QL) capsule is a traditional Chinese medicine that is widely used for the treatment of patients with chronic heart failure (CHF) of all etiologies, although the exact mechanisms of action remain unclear. CHF leads to pulmonary vascular remodelling and thickening of the alveolar-capillary barrier that may be important mechanisms in the poor clinical outcome in patients with end-stage heart failure. We examined whether QL could improve lung injury in ischemic CHF by reducing lung remodeling. Rats with myocardial infarct received QL (1.0 g/kg/day) for 4 weeks. Echocardiographic and morphometric measurements were obtained followed by echocardiography, histological staining, and immunohistochemical analysis of lung sections. CHF caused significant lung structural remodeling evidenced by collagen deposition and thickening of the alveolar septa after myocardial infarct that were greatly improved by QL. Lung weight increased after infarct with no evidence of pulmonary edema and was normalized by QL. QL also reduced lung transforming growth factor-ß1 (TGF-ß1), p-Smad3, tumor necrosis factor-α (TNF-α), and Toll-like receptor-4 (TLR4) expression. Thus, QL reduces lung remodeling associated with CHF, mainly by suppressing the TGF-ß1/Smad3 signaling pathway. The mechanism may also involve inhibition of TLR4 intracellular signaling.
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OBJECTIVE: To observe the influence of Qingrehuatan decoction (QRHT) on serum metabolic profile in young essential hypertension (YEH) patients with abundant phlegm-heat syndrome and provide a basis for treatment with the decoction. METHODS: Twelve male YEH patients were randomly selected and serum samples were collected for examination before and after 4 weeks of the treatment with QRHT. Twelve healthy males were randomly selected and their serum samples were collected as a control. All serum samples were detected using metabolomic technology with 1H nuclear magnetic resonance. Differences in metabolites were studied by principal component analysis and partial least squares-discriminate analysis, which produced scores and loadings plots. RESULTS: After 4 weeks of treatment, serum substances could be distinguished between the YEH patients with abundant phlegm-heat syndrome and the control patients. The specific serum endog- enous metabolites tended to improve after the treatment. QRHT can appropriately increase the levels of glucose, lactic acid, citric acid, high-density lipoprotein, phosphatidylcholine, glycerophosphate choline, hydroxybutyrate, alanine, and glutamate. QRHT could also decrease the levels of low-density lipoprotein/very low-density lipoprotein, lipids, N-acetyl glycoprotein, and O-acetyl glycoprotein. CONCLUSION: QRHT can effectively ameliorate metabolic disorders in YEH Patients with abundant phlegm-heat syndrome. 1H NMR-based metabolomic technology can provide an objective basis for the treatment of YEH patients with abundant phlegm-heat syndrome using QRHT.
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Medicamentos Herbarios Chinos/uso terapéutico , Hipertensión/tratamiento farmacológico , Suero/química , Adulto , Hipertensión Esencial , Humanos , Hipertensión/sangre , Hipertensión/metabolismo , Espectroscopía de Resonancia Magnética , Masculino , Metabolómica , Moco/metabolismo , Suero/metabolismo , Resultado del TratamientoRESUMEN
The catalytic asymmetric aza-ene reactions of 3-indolylmethanols with cyclic enaminones and the highly enantioselective aza-ene reactions utilizing cyclic aza-ene components have been established, which directly assemble isatin-derived 3-indolylmethanols and dimedone-derived enaminones into C3-functionalized chiral indoles with one all-carbon quaternary stereogenic center in high yields and excellent enantioselectivities (up to 99% yield, up to 95:5 er).
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P-5m, an octapeptide derived from domain 5 of HKa, was initially found to inhibit the invasion and migration of melanoma cells. The high metastatic potential of melanoma cells was prevented by the HGK motif in the P-5m peptide in vitro and in an experimental lung metastasis model, suggesting that P-5m may play an important role in the regulation of tumor metastasis. The aim of this study was to measure the effect of P-5m on tumor metastasis of human hepatocarcinoma cell line (HCCLM3) in vitro and in vivo in a nude mouse model of hepatocellular carcinoma (HCC), and detect the mechanisms involved in P-5m-induced anti-metastasis. By gelatin zymography, matrix metallo-proteinases 2 (MMP-2) activity in HCCLM3 was dramatically diminished by P-5m peptide. In addition, the migration and metastasis of HCCLM3 cells was also inhibited by the peptide in vitro. In an orthotopic model of HCC in nude mice, P-5m treatment effectively reduced the lung metastasis as well as the expression of MMP-2 in the tumor tissues. Overall, these observations indicate an important role for P-5m peptide in HCC invasion and metastasis, at least partially through modulation MMP-2 expression. These data suggests that P-5m may have therapeutic potential in metastatic human hepatocarcinoma.
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Antineoplásicos/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Pulmonares/prevención & control , Neoplasias Pulmonares/secundario , Metaloproteinasa 2 de la Matriz/biosíntesis , Oligopéptidos/farmacología , Animales , Productos Biológicos/farmacología , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Modelos Animales de Enfermedad , Femenino , Humanos , Quininógeno de Alto Peso Molecular/genética , Quininógeno de Alto Peso Molecular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Invasividad Neoplásica , Metástasis de la NeoplasiaRESUMEN
In the title compound, C(26)H(19)ClN(2)O, the 2-chloro-phenyl group forms dihedral angles of 59.6â (1) and 31.9â (1)° with the phenyl rings. The two phenyl rings are inclined at a dihedral angle of 32.9â (1)° with respect to each other. In the crystal, an inter-molecular C-Hâ¯N hydrogen bond links the mol-ecules into a polymeric chain running along the c axis.
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In the title compound, C(22)H(21)N, the pyridine ring adopts a distorted boat conformation, while the adjacent pyran ring adopts a chair conformation; the heterocyclic rings make a dihedral angle of 40.1â (2)° with each other.
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The sensitizing effects of ten surfactants, such as cetyl trimethyl ammonium bromide (CTMAB) and cetyl pyridinium chloride (CPC), on the determination of aluminum were studied. The results showed that the cationic surfactants in the experiment were good sensitizers for the determination of aluminum, and the sensitization time was about 3.0. On the other hand, anionic surfactants had inhibition action, while particular surfactants had no action. With the sensitizing agent of CTMAB, the operating parameters of the spectrometer and the effects of CTMAB, solution medium and interfering elements in aluminum-nickel alloy sample were studied. The content of aluminum in aluminum-nickel alloy sample was determined by air-acetylene flame atomic absorption spectrometry, the linear range of aluminum of this method was 0.10-2.0 g x L(-1), the relative standard deviation was 2.6%, and the recoveries were in the range of 97%-103%.