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1.
Front Neurol ; 15: 1381438, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38784915

RESUMEN

Background: It is critical to accurately and noninvasively evaluate the stented parent artery of intracranial aneurysms (IAs) with endovascular treatment. Objective: To investigate high-resolution vessel wall imaging (HR-VWI) for quantitative and qualitative evaluation of in-stent stenosis (ISS) in IAs treated with stent placement (SP). Methods: Fifty-five patients (58 aneurysms) underwent HR-VWI, contrast-enhanced (CE)-HR-VWI, CE-MR angiography (MRA), time-of-flight (TOF)-MRA, and digital subtraction angiography (DSA) six months after SP, and the reliability of quantitative stent lumen measurements was evaluated by intraclass correlation coefficient (ICC) analysis. Agreement and correlation of quantitative evaluation were estimated by comparing the four MR imaging modalities with DSA. The diagnostic performance for >0%, ≥25%, and ≥50% of ISS degrees and overall diagnostic accuracy for the ISS degrees of the four MR imaging modalities were calculated to qualitative evaluation. Results: The reliability of CE-HR-VWI and HR-VWI for ISS quantitative measurements was excellent (ICC 0.955-0.989). The agreement and correlation of CE-HR-VWI, HR-VWI versus DSA for ISS quantitative measurements were better than those of CE-MRA and TOF-MRA (p < 0.05). The diagnostic performance for distinguishing the degree of ISS >0%, ≥25%, and ≥50% by CE-HR-VWI and HR-VWI was superior to CE-MRA and TOF-MRA, and their overall diagnostic accuracy was 96.55 and 94.83%, respectively. HR-VWI and CE-HR-VWI were not statistically significant in the quantitative and qualitative evaluation of ISS performance (p > 0.05). Conclusion: HR-VWI and CE-HR-VWI have similar performance and value in the quantitative and qualitative evaluation of ISS, and HR-VWI without contrast media could be used as an ideal long-term follow-up approach after SP treatment for IAs.

2.
Molecules ; 29(6)2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38543035

RESUMEN

To investigate the influence of deashing on fusion characteristics, a combined method of water and acid washing with different sequences (water washing followed by acid washing, and acid washing followed by water washing) was used to treat the biochar of bamboo shoot shells (BBSSs). The results show that deashing decreased the K content of the biochar from 50.3% to 1.08% but increased the Si content from 33.48% to 89.15%. The formation of silicates and aluminosilicates from alkali metal oxides with silicon was an inevitable result of ash phase transformation at the high temperatures used to improve the fusion temperature (>1450 °C). The thermochemical behavior of ash mainly occurs at 1000 °C. The deashing treatment significantly reduced the reaction intensity during the high-temperature process. This significantly increased the thermal stability of the ash. The adjustment of the washing sequence had a slight impact on the chemical compositions, but the differences in ash micromorphology were obvious. Deashing treatments with different washing sequences can significantly improve ash fusion properties effectively and reduce the risk of scaling, slagging, and corrosion. This study provides a new and reasonable strategy for the deashing of biochar to commercially utilize bamboo shoot shell resources.


Asunto(s)
Álcalis , Carbón Orgánico , Carbón Orgánico/química , Temperatura , Agua , Ceniza del Carbón
3.
Medicine (Baltimore) ; 102(50): e36393, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38115323

RESUMEN

The aim of the present study was to analyze the clinical features, treatments, and short-term prognoses of 18 patients with novel coronavirus pneumonia (NCP) in order to provide reference for further clinical prevention and control of the epidemic. From January 29 to February 29, 2020, data from 18 patients with NCP who were positive for the 2019 novel coronavirus nucleic acid test were collected, and their clinical manifestations, laboratory tests, imaging features, and treatment protocols were analyzed retrospectively. From among the 18 patients with NCP, 9 (50%) were imported cases and 9 (50%) had contact histories with confirmed adult patients. Clinical classification was mainly of the normal type (16 cases, 88.9%). Fever and cough were common clinical symptoms, and the main laboratory indices were lymphocytopenia and leukocytopenia. The main imaging findings yielded ground-glass opacity in 12 cases (66.7%) and patchy opacity in 9 cases (50%). All 18 patients were treated with antiviral therapy and targeted treatment in accordance with their symptoms, returned negative nucleic acid tests (9-23 days) after their treatment, and were cured and discharged by March 5, 2020. During the early stages in Deyang, most patients with NCP were input cases; in the later stages, the main route of infection was close contact within the family. Close contact history in epidemiology, nucleic acid detection, and chest imaging were important references for diagnosis. Antiviral therapy resulted in good therapeutic effects. Adopting multi-departmental consultation and remote consultation in combination with traditional Chinese medicine treatment and psychological counseling may result in a good short-term prognosis.


Asunto(s)
COVID-19 , Ácidos Nucleicos , Adulto , Humanos , SARS-CoV-2 , Estudios Retrospectivos , Antivirales , China/epidemiología
4.
Front Neurol ; 14: 1244014, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37745657

RESUMEN

Objective: To investigate the predictive value of Whole Brain CT Perfusion (WB-CTP) combined with the ABCD3 score in patients with transient ischemic attack (TIA). Methods: A total of 336 TIA patients with TIA underwent WB-CTP and ABCD3 score assessment within 48 h of admission. Spearman correlation test was performed to analyze the relationship between the degree of vascular stenosis, relative perfusion values, and ABCD3 score. Logistic regression analysis was used to identify independent risk factors for secondary cerebral infarction. Receiver operating characteristic (ROC) curves were generated to evaluate the predictive value of relative cerebral blood flow (rCBF), degree of vascular stenosis, ABCD3 score, and the WB-CTP-ABCD3 combined model for secondary cerebral infarction after TIA. Calibration curves and H-L tests were used to evaluate the predictive efficacy of the model. Results: Among the 336 TIA patients, 143 showed abnormal perfusion areas and 146 had responsible vessel stenosis. The degree of vascular stenosis, relative time-to-maximum (rTmax), and relative mean transit time (rMTT) were positively correlated with the ABCD3 score, while rCBF and relative cerebral blood volume (rCBV) were negatively correlated with the ABCD3 score. ROC curve analysis identified a cutoff value of 0.8205 for rCBF, with a sensitivity of 84.10% and specificity of 58.10% for distinguishing the cerebral infarction group from the non-cerebral infarction group. Furthermore, rCBF ≤ 0.8205, degree of vascular stenosis, and ABCD3 score > 6 were identified as independent risk factors for secondary cerebral infarction in TIA patients within 90 days in TIA patients. The AUC of the WB-CTP-ABCD3 combined model for predicting secondary cerebral infarction within 90 days was 0.836. The model risk was assessed by plotting calibration curves. The value of p for the H-L goodness of fit test was 0.366 (p > 0.05), which indicated that the difference between the obtained model and the perfect model were statistically insignificant. Conclusion: The combined model of WB-CTP-ABCD3 shows promise as a valuable method for predicting secondary cerebral infarction within 90 days following TIA.

5.
Exp Ther Med ; 26(3): 449, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37614430

RESUMEN

Water-based and oil-based contrast media are both widely used in clinical practice for patients receiving hysterosalpingography (HSG). However, minor controversy exists about whether the oil-based contrast medium has a superior fertility-enhancing effect during HSG. The present meta-analysis intended to comprehensively compare the fertility outcomes of patients receiving either an oil-based or a water-based contrast medium during HSG. Web of Science, PubMed, Excerpta Medica Database, Cochrane, China National Knowledge Infrastructure, Wanfang Data and China Science and Technology Journal Database were examined for literature comparing the fertility enhancement between oil-based and water-based contrast media during HSG up to November 10, 2022 and there was no cut off for studies published earlier than any given year. Data for clinical pregnancy, ongoing pregnancy, live birth, miscarriage and ectopic pregnancy were extracted and analyzed. A total of 11 studies with 2,462 patients receiving oil-based contrast medium and 2,830 patients receiving water-based contrast medium during HSG were included. Relative risks (RRs) and 95% confidence intervals (CIs) were presented for outcome assessment, and the random effects model was utilized for all analyses. Publication bias was analyzed using Egger's and Begg's tests. The results indicated that the rate of clinical pregnancy was increased using oil-based contrast medium compared with water-based contrast medium [relative risk (RR) (95% CI), 1.29 (1.07, 1.54); P=0.006]. In addition, the rate of ongoing pregnancy [RR (95% CI), 1.39 (1.22, 1.59); P#x003C;0.001] and live birth [RR (95% CI), 1.41 (1.07, 1.87); P=0.016] were also increased using oil-based contrast medium compared with water-based contrast medium. However, miscarriage [RR (95% CI), 1.06 (0.61, 1.86); P=0.833] and ectopic pregnancy [RR (95% CI), 0.66 (0.18, 2.36); P=0.518] were not affected by using oil-based or water-based contrast medium. Begg's test and Egger's test suggested that no publication bias of clinical pregnancy, ongoing pregnancy, live birth, miscarriage and ectopic pregnancy existed (all P>0.05), which indicated the stability of the present meta-analysis. In conclusion, the oil-based contrast medium enhances fertility outcomes compared with the water-based contrast medium in patients receiving HSG.

6.
J Nutr ; 153(1): 167-175, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36913450

RESUMEN

BACKGROUND: Circulating zinc (Zn) concentrations are lower than normal in patients with Parkinson disease (PD). It is unknown whether Zn deficiency increases the susceptibility to PD. OBJECTIVES: The study aimed to investigate the effect of dietary Zn deficiency on behaviors and dopaminergic neurons in a mouse model of PD and to explore potential mechanisms. METHODS: Male C57BL/6J mice aged 8-10 wk were fed Zn adequate (ZnA; 30 µg/g) or Zn deficient (ZnD; <5 µg/g) diet throughout the experiments. Six weeks later 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was injected to generate the PD model. Controls were injected with saline. Thus, 4 groups (Saline-ZnA, Saline-ZnD, MPTP-ZnA, and MPTP-ZnD) were formed. The experiment lasted 13 wk. Open field test, rotarod test, immunohistochemistry, and RNA sequencing were performed. Data were analyzed with t-test, 2-factor ANOVA, or Kruskal-Wallis test. RESULTS: Both MPTP and ZnD diet treatments led to a significant reduction in blood Zn concentrations (PMPTP = 0.012, PZn = 0.014), reduced total distance traveled (PMPTP < 0.001, PZn = 0.031), and affected the degeneration of dopaminergic neurons in the substantia nigra (PMPTP < 0.001, PZn = 0.020). In the MPTP-treated mice, the ZnD diet significantly reduced total distance traveled by 22.4% (P = 0.026), decreased latency to fall by 49.9% (P = 0.026), and reduced dopaminergic neurons by 59.3% (P = 0.002) compared with the ZnA diet. RNA sequencing analysis revealed a total of 301 differentially expressed genes (156 upregulated; 145 downregulated) in the substantia nigra of ZnD mice compared with ZnA mice. The genes were involved in a number of processes, including protein degradation, mitochondria integrity, and α-synuclein aggregation. CONCLUSIONS: Zn deficiency aggravates movement disorders in PD mice. Our results support previous clinical observations and suggest that appropriate Zn supplementation may be beneficial for PD.


Asunto(s)
Desnutrición , Enfermedad de Parkinson , Ratones , Masculino , Animales , Enfermedad de Parkinson/metabolismo , Neuronas Dopaminérgicas/metabolismo , Ratones Endogámicos C57BL , Dieta , Dopamina/metabolismo , Zinc , Sustancia Negra/metabolismo , Modelos Animales de Enfermedad , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/metabolismo , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología
7.
J Int Med Res ; 50(6): 3000605221106285, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35770997

RESUMEN

OBJECTIVES: We aimed to construct novel prognostic models based on RNA-binding proteins (RBPs) in breast cancer (BRCA) and explore their roles in this disease and their effects on tumor-infiltrating immune cells (TIICs). METHODS: Datasets were downloaded from the Gene Expression Omnibus (GEO) database. Functions and prognostic values of RBPs were systematically investigated using a series of bioinformatics analysis methods. TIICs were assessed using CIBERSORT. RESULTS: Overall, 138 differentially expressed RBPs were identified, of which 86 were upregulated and 52 were downregulated. Of these, 13 RBPs were identified as prognosis-related and adopted to construct an overall survival (OS) model, while 12 RBPs were used for the relapse-free survival (RFS) model. High-risk patients had poorer OS and RFS rates than low-risk patients. The results indicate that the OS and RFS models are good prognostic models with reliable predictive abilities. In addition, the proportions of CD8, CD4 naïve, and CD4 memory resting T cells, as well as resting dendritic cells, were significantly different between the low-risk and high-risk groups in the OS model. CONCLUSIONS: OS and RFS signatures can be used as reliable BRCA prognostic biomarkers. This work will help understand the prognostic roles and functions of RBPs in BRCA.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Mama/genética , Biología Computacional/métodos , Femenino , Humanos , Recurrencia Local de Neoplasia , Pronóstico , Proteínas de Unión al ARN/genética
8.
Front Genet ; 13: 856493, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35432448

RESUMEN

CLEC16A is a membrane-associated endosomal protein implicated in regulating autophagy and antigen presentation. Its genetic variants are broadly associated with multiple autoimmune diseases. Parkinson's disease (PD), which undergoes autophagy disruption and neuroinflammation, has been clinically observed, for an extensive amount of time, to be associated with autoimmune diseases. In this study, we aimed to understand whether the autoimmune disease associated CLEC16A variants pleiotropically modulate PD risk. Five of such CLEC16A variants, including rs6498169, rs12708716, rs12917716, rs7200786, and rs2903692, were selected and analyzed in a Han Chinese cohort comprising 515 sporadic PD patients and 504 controls. Results showed that rs6498169 and rs7200786 were significantly associated with PD susceptibility (p = 0.005 and 0.004, respectively; recessive model, p = 0.002 and 0.001, respectively). Rs6498169 was also associated with the PD subtype of postural instability/gait difficulty (p = 0.002). Haplotype analysis showed that the AAG module in order of rs6498169, rs12708716, and rs2903692 was associated with the highest risk for PD (p = 0.0047, OR = 1.42, 95% CI = 1.11-1.82). Functional annotation analyses suggested that rs6498169 had high probability to affect transcription factor binding and target gene expression. In summary, the current study demonstrates that the autoimmune disease associated CLEC16A variants convey risk of PD in Han Chinese. Our findings suggest a pleiotropic role of CLEC16A and strengthen the link between PD and autoimmune diseases.

9.
Dis Model Mech ; 15(3)2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35023548

RESUMEN

Parkinson's disease (PD) is associated with α-synuclein-based Lewy body pathology, which has been difficult to observe in conventional two-dimensional (2D) cell culture and even in animal models. We herein aimed to develop a three-dimensional (3D) cellular model of PD to recapitulate the α-synuclein pathologies. All-trans-retinoic acid-differentiated human SH-SY5Y cells and Matrigel were optimized for 3D construction. The 3D cultured cells displayed higher tyrosine hydroxylase expression than 2D cells and improved dopaminergic-like phenotypes, as suggested by RNA-sequencing analyses. Multiple forms of α-synuclein, including monomer, and low- and high-molecular mass oligomers, were differentially present in the 2D and 3D cells, but mostly remained unchanged upon N-methyl-4-phenyl pyridine or rotenone treatment. Phosphorylated α-synuclein was accumulated, and detergent-insoluble α-synuclein fraction was observed, in the neurotoxin-treated 3D cells. Importantly, Lewy body-like inclusions were captured in the 3D system, including proteinase K-resistant α-synuclein aggregates, ubiquitin aggregation, and ß-amyloid and ß-sheet protein deposition. The study provides a unique and convenient 3D model of PD that recapitulates critical α-synuclein pathologies and should be useful in multiple PD-associated applications.


Asunto(s)
Enfermedad de Parkinson , Línea Celular Tumoral , Colágeno , Combinación de Medicamentos , Humanos , Laminina/metabolismo , Cuerpos de Lewy/metabolismo , Enfermedad de Parkinson/patología , Proteoglicanos , alfa-Sinucleína/metabolismo
10.
Acta Clin Croat ; 61(2): 193-197, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36818924

RESUMEN

The aim was to investigate detection of pulmonary alveolar lavage fluid tuberculosis DNA by real-time fluorescent polymerase chain reaction (RT-PCR) combined with clinical application of the sputum smear-negative pulmonary tuberculosis diagnosis with TB interferon-γ release assay (TB-IGRA). From October 2014 to October 2015, 632 outpatients and inpatients treated in our hospital were randomly selected, of which 459 patients as the research group managed with RT-PCR detection combined with TB-IGRA and 173 patients as the control group undergoing electronic bronchoscopy alveolar lavage fluid detection, with detection results statistically evaluated. The positive rate in the research group was 96.51%, i.e. significantly higher than that in the control group (66.47%), yielding a statistically significant difference (χ2=109.68, p=0.00). The true positive rate was 97.7% in the research group and 67.92% in the control group; the true positive rate was significantly higher in the research group patients as compared with the control group, yielding a statistically significant difference (χ2=112.04, p=0.00). The sensitivity and specificity, as well as Youden index were significantly higher in the research group as compared with the control group. In conclusion, TB DNA detection by RT-PCR combined with TB-IGRA is a very good method of diagnosing tuberculosis, and it can be implemented in clinical diagnosis of pulmonary tuberculosis.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Pulmonar , Tuberculosis , Humanos , Ensayos de Liberación de Interferón gamma/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Esputo , Tuberculosis/diagnóstico , Tuberculosis Pulmonar/diagnóstico , Sensibilidad y Especificidad , ADN
11.
Mol Ther Nucleic Acids ; 25: 455-467, 2021 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-34513288

RESUMEN

Non-coding RNAs play essential roles in breast cancer progression by regulating proliferation, differentiation, invasion, and metastasis. However, our understanding of most microRNAs (miRNAs) and long noncoding RNAs (lncRNAs) in breast cancer is still limited. miR-586 has been identified as an important factor in the progression of some types of cancer, but its exact function and relative regulation mechanisms in breast cancer development need to be further investigated. In this study, we showed miR-586 functioned as an oncogene by promoting breast cancer proliferation and metastasis both in vitro and in vivo. Meanwhile, miR-586 induced Wnt/ß-catenin activation by directly targeting Wnt/ß-catenin signaling antagonists SFRP1 and DKK2/3. Moreover, we demonstrated that LINC01189 functioned as a tumor suppressor and inhibited breast cancer progression through inhibiting an epithelial-mesenchymal transition (EMT)-like phenotype by sponging miR-586. In addition, ß-catenin/TCF4 transactivated ZEB1, resulting in a transcriptional repression of LINC01189 expression. In conclusion, our data uncovered the LINC01189-miR-586-ZEB1 feedback loop and provided a novel mechanism participating in the regulation of Wnt/ß-catenin signaling in breast cancer progression.

12.
Infect Drug Resist ; 14: 467-473, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33603410

RESUMEN

OBJECTIVE: This study aimed to investigate the expression of natural killer (NK) cell subsets in patients with acquired immune deficiency syndrome (AIDS) and deep fungal infections and the significance of such expression. METHODS: A total of 829 patients with AIDS, who were treated in People's Hospital of Deyang City our hospital between January 2011 and March 2019, were enrolled in the study. They were divided into two groups: those with human immunodeficiency virus (HIV) and invasive fungal infection (IFI) (HIV + IFI) (n = 390) and those with HIV and no IFI (HIV + non-IFI) (n = 439). Another 200 healthy volunteers were enrolled as the control group. The numbers of NK cell subsets in each group were compared. RESULTS: The level of NK cells, number of NK cells in all lymphocytes, proportions of CD56bright, CD56dim, and CD56dim NK cells in NK cells, and the level of CD56-CD16+ NK cells were significantly lower in the HIV + IFI group than in the HIV + non-IFI group and control group (P < 0.05). Moreover, CD4+ T, CD4+/CD8+, and NK cells were negatively correlated with HIV-RNA expression (P < 0.05). CONCLUSION: A combination of AIDS and deep fungal infection can change the immune status of a patient. This condition can be diagnosed early through the detection of NK cell expression.

13.
Theranostics ; 10(23): 10729-10742, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32929377

RESUMEN

Background: Breast cancer is the most common malignancy, and approximately 70% of breast cancers are estrogen receptor-α (ERα) positive. The anti-estrogen tamoxifen is a highly effective and commonly used treatment for patients with ER+ breast cancer. However, 30% of breast cancer patients fail adjuvant tamoxifen therapy and most of metastatic breast cancer patients develop tamoxifen resistance. Although increasing evidence suggests that microRNA (miRNA) dysregulation influences tamoxifen sensitivity, the mechanism of the cross-talk between miRNA and ERα signaling remains unclear. miR-575 has been reported to be involved in carcinogenesis and progression, however, the role of miR-575 in breast cancer remains limited. The aim of this study was to understand the mechanism of miR-575 in breast cancer tamoxifen resistance. Method: RT-qPCR was employed to assess miR-575 expression in breast cancer tissues and cell lines. The association of miR-575 expression with overall survival in patients with breast cancer was evaluated with KM plotter. Additionally, the effects of miR-575 on breast cancer proliferation and tamoxifen sensitivity were investigated both in vitro and in vivo. Bioinformatic analyses and luciferase reporter assays were performed to validate CDKN1B and BRCA1 as direct targets of miR-31-5p. The ERα binding sites in the miR-575 promoter region was validated with ChIP and luciferase assays. ERα interactions with CDKN1B, cyclin D1 or BRCA1 were determined by IP analysis, and protein expression levels and localization were analyzed by western blotting and immunofluorescence, respectively. Results: miR-575 levels were higher in ER+ breast cancer than in ER- breast cancer and patients with high miR-575 expression had a significantly poorer outcome than those with low miR-575 expression. ERα bound the miR-575 promoter to activate its transcription, and tamoxifen treatment downregulated miR-575 expression in ER+ breast cancer. Overexpression of miR-575 decreased tamoxifen sensitivity by targeting CDKN1B and BRCA1. CDKN1B and BRCA1 were both able to antagonize ERα activity by inhibiting ERα nuclear translocation and interaction with cyclin D1. Furthermore, miR-575 expression was found to be upregulated in ER+ breast cancer cell with acquired tamoxifen resistance, whereas depletion of miR-575 partially re-sensitized these cells to tamoxifen by regulation of CDKN1B. Conclusions: Our data reveal the ERα-miR-575-CDKN1B feedback loop in ER+ breast cancer, suggesting that miR-575 can be used as a prognostic biomarker in patients with ER+ breast cancer, as well as a predictor or a promising target for tamoxifen sensitivity.


Asunto(s)
Neoplasias de la Mama/terapia , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Resistencia a Antineoplásicos/genética , Receptor alfa de Estrógeno/metabolismo , MicroARNs/metabolismo , Tamoxifeno/farmacología , Animales , Proteína BRCA1/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Mama/patología , Mama/cirugía , Neoplasias de la Mama/genética , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Línea Celular Tumoral , Quimioterapia Adyuvante/métodos , Ciclina D1/metabolismo , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Resistencia a Antineoplásicos/efectos de los fármacos , Receptor alfa de Estrógeno/genética , Retroalimentación Fisiológica , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Estimación de Kaplan-Meier , Mastectomía , Ratones , MicroARNs/agonistas , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Mutagénesis Sitio-Dirigida , Pronóstico , Regiones Promotoras Genéticas/genética , Tamoxifeno/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto
14.
J Hazard Mater ; 153(1-2): 269-75, 2008 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-17900802

RESUMEN

The printed circuit board (PCB) has a metal content of nearly 28% metal, including an abundance of nonferrous metals such as copper, lead, and tin. The purity of precious metals in PCBs is more than 10 times that of rich-content minerals. Therefore, the recycling of PCBs is an important subject, not only from the viewpoint of waste treatment, but also with respect to the recovery of valuable materials. Compared with traditional process the corona electrostatic separation (CES) had no waste water or gas during the process and it had high productivity with a low-energy cost. In this paper, the roll-type corona electrostatic separator was used to separate metals and nonmetals from scraped waste PCBs. The software MATLAB was used to simulate the distribution of electric field in separating space. It was found that, the variations of parameters of electrodes and applied voltages directly influenced the distribution of electric field. Through the correlation of simulated and experimental results, the good separation results were got under the optimized operating parameter: U=20-30 kV, L=L(1)=L(2)=0.21 m, R(1)=0.114, R(2)=0.019 m, theta(1)=20 degrees and theta(2)=60 degrees .


Asunto(s)
Conservación de los Recursos Naturales , Electrónica , Electricidad Estática , Administración de Residuos/métodos , Residuos , Simulación por Computador , Electrodos
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