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2.
Zhonghua Yan Ke Za Zhi ; 60(8): 658-664, 2024 Aug 11.
Artigo em Chinês | MEDLINE | ID: mdl-39085155

RESUMO

Objective: To evaluate clinical outcomes and visual quality after femtosecond laser-assisted in situ keratomileusis (FS-LASIK) performed with the Q-value-guided optimized monocular vision protocol (Custom-Q) for correction of low-to-moderate myopia and compensation for age-related accommodation deficiency. Methods: A prospective study was performed based on patients with myopia and age-related accommodation deficiency, who underwent Custom-Q FS-LASIK in the Peking University Third Hospital from October 2022 to October 2023. Monocular and binocular distance, intermediate, and near visual acuities, simulated whole-course visual acuity (binocular defocus curve), objective and subjective refractions, anterior corneal Q factor, anterior corneal higher-order aberrations and a subjective questionnaire assessing near visual acuity and visual quality were evaluated at 3 months postoperatively. Visual acuity was recorded using the logarithm of the minimum angle of resolution. The data were analyzed using the t-test and the Wilcoxon rank-sum test. Results: A total of 45 patients (90 eyes) who met the inclusion criteria and completed the 3-month follow-up were included in the study. The mean age of the 21 men (42 eyes) and 24 women (48 eyes) was (42.82±2.72) years. During the 3-month follow-up, all the patients achieved binocular uncorrected distance visual acuity not less than 0.00 and uncorrected near visual acuity not less than 0.20. Defocus curves revealed better results at 3 months postoperatively [0.00 (-0.08, 0.00), -0.08 (-0.08, 0.00)] at intermediate and near vergence (-1.50 to -1.00 D) compared to the preoperative values [0.00 (-0.08, 0.05), -0.08 (-0.08, 0.00)] (P<0.05). All the 45 patients maintained 0.10 or better vision at the defocus range from -2.50 to 0.00 D. The Q value in the dominant eyes was more positive postoperatively (0.01±0.26 vs.-0.15±0.14, P<0.05), while in the nondominant eyes, the Q value and corneal spherical aberration coefficient became more negative than those before surgery (-0.27±0.32 vs.-0.14±0.11, P<0.05; 0.08±0.05 vs. 0.12±0.03, P<0.05). The questionnaire demonstrated 42 (93.3%) patients were satisfied with near vision. The three most commonly reported visual discomforts after surgery were blurred vision, glare and halos. These symptoms were all mild to moderate in severity and did not interfere with daily life. Conclusion: For myopic patients with age-related accommodation deficiency, the Custom-Q algorithm proved to be a safe and effective way to achieve acceptable near vision and visual quality without compromising distance vision.


Assuntos
Ceratomileuse Assistida por Excimer Laser In Situ , Lasers de Excimer , Miopia , Acuidade Visual , Humanos , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Feminino , Masculino , Miopia/cirurgia , Estudos Prospectivos , Adulto , Lasers de Excimer/uso terapêutico , Presbiopia/cirurgia , Córnea/cirurgia , Acomodação Ocular , Refração Ocular , Resultado do Tratamento , Pessoa de Meia-Idade
3.
Zhonghua Wei Chang Wai Ke Za Zhi ; 26(12): 1132-1137, 2023 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-38110274

RESUMO

This article describes the surgical treatment of fecal incontinence. There are many surgical methods for fecal incontinence, and each treatment has its own advantages and disadvantages and indications. The appropriate surgical procedure should be selected according to the patient's history, anatomical structure and severity of incontinence. Injectable bulking agents is suitable for passive fecal incontinence. Sphincteroplasty is suitable for patients with sphincter injury caused by vaginal delivery or surgical trauma. Sacral nerve stimulation and posterior tibial nerve stimulation are relatively conservative methods. Gracilomyoplasty, artificial anal sphincter or magnetic anal sphincter can be used in the treatment of refractory fecal incontinence, but with many complications. Colostomy is the ideal choice for patients who have failed to respond to conservative treatment and cannot undergo these procedures.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Incontinência Fecal , Feminino , Humanos , Incontinência Fecal/etiologia , Canal Anal/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Complicações Intraoperatórias , Fezes , Resultado do Tratamento
4.
Zhonghua Yan Ke Za Zhi ; 59(10): 851-857, 2023 Oct 11.
Artigo em Chinês | MEDLINE | ID: mdl-37805419

RESUMO

Anterior segment optical coherence tomography (AS-OCT) has the characteristics of non-contact, noninvasive, high sensitivity, and repeatability, and offers high-resolution in vivo imaging of the structures of the anterior eye segment. It can be used in the diagnosis and assistance of conditions related to the anterior eye segment. This review provides an update on the research and clinical applications of AS-OCT in corneal refractive surgery, including preoperative keratoconus screening, intraoperative real-time visualization of corneal structures, postoperative corneal evaluation, and management of postoperative complications. We also explore the potential application of AS-OCT in combination with corneal biomechanical detection for corneal refractive surgery.


Assuntos
Ceratocone , Procedimentos Cirúrgicos Refrativos , Humanos , Tomografia de Coerência Óptica/métodos , Córnea/cirurgia , Segmento Anterior do Olho/diagnóstico por imagem , Ceratocone/cirurgia , Ceratocone/diagnóstico
5.
Zhonghua Wei Chang Wai Ke Za Zhi ; 26(9): 885-888, 2023 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-37709700

RESUMO

Objective: There is no standard method for esophageal remnant gastric reconstruction for proximal gastrectomy. Reflux esophagitis caused by esophagogastrostomy remains a difficult surgical problem. To report the preliminary surgical results of novel esophagus-conical remnant gastric side overlap anastomosis (CGEO) , with particular emphasis on postoperative esophageal reflux. Methods: In June 2022, we developed a novel CGEO for laparoscopic proximal gastrectomy on two patients with Siewert type II esophagogastric junction adenocarcinoma. Surgical procedures for CGEO: (1) Laparoscopic proximal gastrectomy and preparation of conically shaped gastric remnant; (2) Determining anastomotic site of residual stomach and esophagus; (3) Side-to-side anastomosis of right esophageal wall to anterior of conical gastric remnant; (4) Valvuloplasty of esophageal stump. Results: Case 1 was a 71-year-old man with an operation time of 305 minutes and was successfully discharged from the hospital on the 9th day after surgery, and the postoperative pathology was T3N0M0. Case 2 was an 82-year-old man with an operation time of 325 minutes. He was discharged on the 10th day after surgery. In both cases, only mild esophageal mucosal changes were seen in gastroscopy, there were no obvious symptoms of esophageal reflux. There was also no significant weight change at half a year after operation. Conclusion: CGEO is moderately safe in radical surgery for proximal gastric cancer, and may have a preventive effect on the occurrence of postoperative esophageal reflux, but long-term results need to be confirmed by further studies with follow-up.


Assuntos
Esofagite Péptica , Refluxo Gastroesofágico , Neoplasias Gástricas , Masculino , Humanos , Idoso , Idoso de 80 Anos ou mais , Neoplasias Gástricas/cirurgia , Anastomose Cirúrgica , Gastrectomia
6.
Zhonghua Yan Ke Za Zhi ; 59(6): 476-480, 2023 Jun 11.
Artigo em Chinês | MEDLINE | ID: mdl-37264578

RESUMO

A 22-year-old male presented with complaints of blurred vision in his right eye over the past 2 years following small incision lenticule extraction (SMILE) surgery conducted 4 years ago. Following a thorough ocular examination and evaluation, he was diagnosed with corneal ectasia in the right eye after the SMILE procedure. Subsequently, the patient underwent corneal cross-linking (CXL) treatment in the right eye to prevent the progression of the condition. After 3 months of treatment, the corneal ectasia remained stable. This article outlines the process of diagnosis and treatment, reviews the corneal conditions prior to the SMILE surgery, and analyzes the possible reasons behind the occurrence of postoperative corneal ectasia.


Assuntos
Doenças da Córnea , Cirurgia da Córnea a Laser , Miopia , Humanos , Masculino , Adulto Jovem , Doenças da Córnea/etiologia , Doenças da Córnea/cirurgia , Substância Própria/cirurgia , Cirurgia da Córnea a Laser/efeitos adversos , Topografia da Córnea , Dilatação Patológica/etiologia , Dilatação Patológica/cirurgia , Lasers de Excimer , Miopia/cirurgia , Miopia/diagnóstico , Refração Ocular , Acuidade Visual
7.
Opt Lett ; 48(9): 2433-2436, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37126291

RESUMO

Extremely strong terahertz (THz) waves are desperately demanded for investigating nonlinear physics, spectroscopy, and imaging in the THz range. However, traditional crystal-/semiconductor-based THz sources have limitations of reaching extremely high amplitude due to the damage threshold of devices. Here, by introducing Raman amplification to the THz range, we propose a novel, to the best of our knowledge, scheme to amplify THz waves in plasma. A long-pulse CO2 pump laser transfers its energy to a multicycle, 10-THz seed in a two-step plasma. By one-dimensional simulations, a 0.87-GV/m, 1.2-ps-duration THz seed is amplified to 10 GV/m in a 5.7-mm-long plasma with an amplification efficiency approaching 1%. The method provides a new technology to manipulate the intensity of THz waves.

8.
Zhonghua Yi Xue Za Zhi ; 103(21): 1585-1590, 2023 Jun 06.
Artigo em Chinês | MEDLINE | ID: mdl-37248056

RESUMO

Cardiac arrest is one of the major public health problems with sudden onset, high mortality and high disability rate. The prevalence of cardiovascular disease continues to rise and the burden of cardiac arrest is increasing in China. It is of great significance to explore more effective prevention and treatment measures to improve the prognosis of patients with cardiac arrest. This article discusses the relevant progress on the treatment ability of emergency and critical cardiovascular diseases, medicines and technologies for cardiac arrest care, and registry studies of cardiac arrest, to further promote the effective improvement of key capacities at various stages of the prevention and treatment of cardiac arrest in China.


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca , Humanos , Parada Cardíaca/terapia , Prognóstico , Sistema de Registros , Saúde Pública
9.
Zhonghua Nei Ke Za Zhi ; 62(4): 374-383, 2023 Apr 01.
Artigo em Chinês | MEDLINE | ID: mdl-37032132

RESUMO

Objectives: To investigated the safety and efficacy of treating patients with acute non-ST-segment elevation myocardial infarction (NSTEMI) and elevated levels of N-terminal pro-hormone B-type natriuretic peptide (NT-proBNP) with levosimendan within 24 hours of first medical contact (FMC). Methods: This multicenter, open-label, block-randomized controlled trial (NCT03189901) investigated the safety and efficacy of levosimendan as an early management strategy of acute heart failure (EMS-AHF) for patients with NSTEMI and high NT-proBNP levels. This study included 255 patients with NSTEMI and elevated NT-proBNP levels, including 142 males and 113 females with a median age of 65 (58-70) years, and were admitted in the emergency or outpatient departments at 14 medical centers in China between October 2017 and October 2021. The patients were randomly divided into a levosimendan group (n=129) and a control group (n=126). The primary outcome measure was NT-proBNP levels on day 3 of treatment and changes in the NT-proBNP levels from baseline on day 5 after randomization. The secondary outcome measures included the proportion of patients with more than 30% reduction in NT-proBNP levels from baseline, major adverse cardiovascular events (MACE) during hospitalization and at 6 months after hospitalization, safety during the treatment, and health economics indices. The measurement data parameters between groups were compared using the t-test or the non-parametric test. The count data parameters were compared between groups using the χ² test. Results: On day 3, the NT-proBNP levels in the levosimendan group were lower than the control group but were statistically insignificant [866 (455, 1 960) vs. 1 118 (459, 2 417) ng/L, Z=-1.25,P=0.21]. However, on day 5, changes in the NT-proBNP levels from baseline in the levosimendan group were significantly higher than the control group [67.6% (33.8%,82.5%)vs.54.8% (7.3%,77.9%), Z=-2.14, P=0.03]. There were no significant differences in the proportion of patients with more than 30% reduction in the NT-proBNP levels on day 5 between the levosimendan and the control groups [77.5% (100/129) vs. 69.0% (87/126), χ²=2.34, P=0.13]. Furthermore, incidences of MACE did not show any significant differences between the two groups during hospitalization [4.7% (6/129) vs. 7.1% (9/126), χ²=0.72, P=0.40] and at 6 months [14.7% (19/129) vs. 12.7% (16/126), χ²=0.22, P=0.64]. Four cardiac deaths were reported in the control group during hospitalization [0 (0/129) vs. 3.2% (4/126), P=0.06]. However, 6-month survival rates were comparable between the two groups (log-rank test, P=0.18). Moreover, adverse events or serious adverse events such as shock, ventricular fibrillation, and ventricular tachycardia were not reported in both the groups during levosimendan treatment (days 0-1). The total cost of hospitalization [34 591.00(15 527.46,59 324.80) vs. 37 144.65(16 066.90,63 919.00)yuan, Z=-0.26, P=0.80] and the total length of hospitalization [9 (8, 12) vs. 10 (7, 13) days, Z=0.72, P=0.72] were lower for patients in the levosimendan group compared to those in the control group, but did not show statistically significant differences. Conclusions: Early administration of levosimendan reduced NT-proBNP levels in NSTEMI patients with elevated NT-proBNP and did not increase the total cost and length of hospitalization, but did not significantly improve MACE during hospitalization or at 6 months.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio sem Supradesnível do Segmento ST , Masculino , Feminino , Humanos , Idoso , Peptídeo Natriurético Encefálico , Simendana/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Fragmentos de Peptídeos , Arritmias Cardíacas , Biomarcadores , Prognóstico
10.
J Appl Microbiol ; 134(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36626796

RESUMO

AIMS: Tobacco (Nicotiana tabacum) is an economically important crop. Root rot caused by Fusarium oxysporum has become a damaging disease in N. tabacum crops grown in Henan province of China. Therefore, the objectives of this study were to screen bacterial isolates against F. oxysporum from rhizosphere soils of tobacco growing areas and to evaluate their antifungal activities, biocontrol effects, and effects on plant growth. METHODS AND RESULTS: Nineteen strains with antifungal inhibition effects of >60% against F. oxysporum were obtained using the method of flat confrontation; the strain Ba-0321 was the strongest, with an antifungal effect of 75%. Moreover, this strain had broad spectrum antimicrobial activity to eight additional tobacco pathogens. The strain was identified as Bacillus velezensis by morphology and the 16S rDNA sequence. The B. velezensis strain Ba-0321 had strong UV resistance as well as tolerance to high temperatures and low nutrition. The bacteria inhibited spore germination and mycelial growth of F. oxysporum under in vitro co-culture conditions. In vivo assays demonstrated that the Ba-0321 strain significantly reduced the pathogenicity of F. oxysporum, resulting in a control effect on tobacco root rot of 81.00%. Simultaneously, the bacteria significantly promoted root development and the growth of tobacco plants. CONCLUSION: Our results confirmed that the B. velezensis strain Ba-0321 has a strong antifungal effect and stress resistance that enable it to be used as a biological control agent for tobacco root rot caused by F. oxysporum. SIGNIFICANCE AND IMPACT OF THE STUDY: Tobacco root rot caused by F. oxysporum has become a damaging disease in China. The B. velezensis strain Ba-0321 has promising application value for controlling tobacco root rot diseases, and it could provide a new biocontrol agent against root rot caused by F. oxysporum in other plant species.


Assuntos
Bacillus , Fusarium , Antifúngicos/farmacologia , Nicotiana , Bacillus/fisiologia , Bactérias , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
11.
Zhonghua Yan Ke Za Zhi ; 58(12): 1111-1116, 2022 Dec 11.
Artigo em Chinês | MEDLINE | ID: mdl-36480900

RESUMO

Presbyopia refers to the decline in the accommodation of eye that occurs with age, symptoms begin to appear after the age of 40 and the clarity of vision at near is insufficient to satisfy an individual's requirements. The correction of presbyopia include restoring natural accommodation and improving symptom. The former is still difficult to achieve at present, while the latter mainly involves wearing convex lens, and with more and more patients wanting to get rid of frame glasses, refractive surgery is gradually promoted and applied. Corneal refractive surgery, especially laser-assisted in situ keratomileusis, is one of the most common methods for surgical correction of presbyopia. We reviewed the recent literature to introduce the mechanism of corneal refractive surgery treating presbyopia and the efficacy of different surgical algorithms.


Assuntos
Lasers de Excimer , Procedimentos Cirúrgicos Refrativos , Humanos , Lasers de Excimer/uso terapêutico
12.
Zhonghua Yan Ke Za Zhi ; 58(4): 241-244, 2022 Apr 11.
Artigo em Chinês | MEDLINE | ID: mdl-35391509

RESUMO

As one of the methods to correct ametropia, refractive surgery has been accepted by more and more patients for its good safety, effectiveness and long-term stability. The two major types of refractive surgery are corneal refractive surgery, which is mainly performed with excimer laser and/or femtosecond laser, and phakic intraocular lens implantation. Each type has its own advantages and disadvantages. Surgeons should choose the best method according to their own technical conditions and the individual situation of each patient. In the preoperative and postoperative evaluation, we should not only pay attention to uncorrected vision and refraction, but also carry out a comprehensive visual quality assessment from both subjective and objective aspects. The ultimate goal of refractive surgery is to maximize patient satisfaction.


Assuntos
Lentes Intraoculares , Miopia , Procedimentos Cirúrgicos Refrativos , Humanos , Lasers de Excimer , Implante de Lente Intraocular , Miopia/cirurgia , Refração Ocular , Acuidade Visual
13.
Zhonghua Yan Ke Za Zhi ; 58(4): 250-258, 2022 Apr 11.
Artigo em Chinês | MEDLINE | ID: mdl-35391511

RESUMO

Objective: To explore the interocular differences in both the increase of corneal higher-order aberrations (HOAs) and axial length elongation, and the correlation between them after orthokeratology lens (OK lens) wear in children with myopic anisometropia. Methods: It was a prospective cohort study. From 2018 to 2019, 31 children with myopic anisometropia who were fitted with OK lenses initially in the Department of Ophthalmology of Peking University Third Hospital were enrolled, including 15 males (30 eyes) and 16 females (32 eyes). The age was (10.7±1.4) years. Before (baseline) and 12 months after wearing OK lenses, corneal aberrations, corneal relative refractive power (corneal RRP, the difference between peripheral corneal refraction and central corneal refraction) and axial length were measured using the Sirius combining a corneal topographer and a tomographer and an IOL-Master intraocular lens biometer in two eyes. Interocular differences in corneal aberrations, corneal RRP and axial length were analyzed by the paired t test and Wilcoxon rank sum test. The Pearson and Spearman correlation analyses were used to explore the correlation between the increase in corneal HOAs, corneal RRP and axial length elongation. Results: At 12 months after wearing OK lenses, 6 children were lost for follow-up, and the data of the remaining 25 children (50 eyes) were evaluated. With 3.0- and 6.0-mm measuring zones of the total cornea and the anterior surface, the increases in total corneal HOAs, coma, spherical aberration of higher myopic eyes were significantly more than fellow lower myopic eyes (all P<0.05). The corneal RRP with 2.0-mm and 2.5-mm radius in the upper cornea and 2.5-mm radius in the inferior cornea of higher myopic eyes were more than fellow lower myopic eyes (t=-2.06, -2.07, -2.42; P=0.05, 0.049, 0.023), but there was no significant interocular difference in corneal RRP in the horizontal meridian direction of the cornea (both the nasal and temporal sides of the cornea) (both P>0.05). The axial length elongation in higher myopic eyes was 0.14 (0.08, 0.20) mm, which was significantly less than that in the contralateral eyes [0.18 (0.14, 0.35) mm] (Z =-3.21, P= 0.001). The interocular difference in axial length decreased from 0.40 (0.34, 0.54) mm at baseline to 0.33 (0.24, 0.54) mm (Z =-3.21, P = 0.001). The increases in HOAs, coma and spherical aberration of the anterior corneal surface with 3.0-mm measuring zone and the increase in coma of the anterior corneal surface with 6.0-mm measuring zone were all negatively correlated with axial length elongation (r=-0.493, -0.606, -0.500, -0.307; P<0.05). But the corneal RRP had no significant correlation with axial length elongation (r=-0.092, -0.104, -0.230, -0.061; P>0.05). Conclusion: After 12 months of OK lens wear, interocular difference in axial length reduced significantly in children with myopic anisometropia, which was related to the larger increase in corneal HOAs of higher myopic eyes than fellow lower myopic eyes, especially coma.


Assuntos
Anisometropia , Lentes de Contato , Miopia , Procedimentos Ortoceratológicos , Comprimento Axial do Olho , Criança , Coma , Córnea , Topografia da Córnea , Feminino , Humanos , Masculino , Miopia/terapia , Estudos Prospectivos , Refração Ocular
14.
Zhonghua Yan Ke Za Zhi ; 58(4): 309-314, 2022 Apr 11.
Artigo em Chinês | MEDLINE | ID: mdl-35391519

RESUMO

Keratoconus is an ectatic corneal disorder and characterized by central and/or inferior temporal corneal thinning in a cone shape. Studies have shown that its pathogenesis is related to changes in tissue proteins, enzymes, immune functions and specific genes, but the exact pathogenesis has not been clearly clarified yet. Hormones such as sex hormones have been found to be associated with keratoconus. This review aims to summarize and analyze the research progress of the effect of hormones on keratoconus and its mechanism, so as to explore the role of hormones in the early diagnosis of keratoconus and find new targets in the treatment of keratoconus, providing reference for clinical work.


Assuntos
Ceratocone , Córnea/patologia , Topografia da Córnea , Hormônios/metabolismo , Humanos , Ceratocone/terapia
16.
Hum Exp Toxicol ; 40(9): 1413-1421, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33686878

RESUMO

OBJECTIVE: This study aimed to investigate the effects of quercetin on the proliferation and invasion in oral squamous cell carcinoma (OSCC) and examine its effect on the activation of the miR-1254/CD36 signaling pathway. METHODS: Proliferation and invasion experiments were performed in the OSCC cell line CAL-27 in which miR-1254 was overexpressed or inhibited. The levels of miR-1254 and CD36 were determined using quantitative real-time polymerase chain reaction and Western blotting assays. RESULTS: Quercetin significantly suppressed the proliferation and invasion of CAL-27 cells in a dose-dependent manner, while up-regulating miR-1254 and down-regulating CD36. The overexpression of miR-1254 also considerably down-regulated CD36 and enhanced the ability of quercetin to inhibit CAL-27 cell survival and invasion. Conversely, the inhibition of miR-1254 significantly up-regulated CD36 and antagonized the inhibitory effects of quercetin. CONCLUSION: Our study suggests that quercetin might suppress the progression of OSCC by activating the miR-1254/CD36 signaling pathway, indicating its potential as a treatment against OSCC.


Assuntos
Antineoplásicos/uso terapêutico , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , MicroRNAs/efeitos dos fármacos , Neoplasias Bucais/tratamento farmacológico , Quercetina/uso terapêutico , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Células Cultivadas/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Bucais/fisiopatologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/fisiopatologia
17.
Phys Rev E ; 104(6-2): 065203, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35030935

RESUMO

Theory of absolute stimulated Brillouin side scattering in an inhomogeneous flowing plasma is presented and verified numerically. The linearized coupling equations are transformed into a Schrödinger equation in k space and solved as an eigenvalue problem. Analytic threshold, growth rate, and scattering geometry are obtained for the pump laser with arbitrary incidence angle. Numerical solutions of the coupling equations show good agreements between the theoretical and numerical absolute thresholds when ion-acoustic wave damping is not too large, and thus an old but famous threshold in [Phys. Fluids 17, 1211 (1974)PFLDAS0031-917110.1063/1.1694867] is corrected. It also indicates that the theoretical analysis is not accurate for strong dampings, since it will overestimate the absolute threshold. Possibility of finding such instability in the current experiments is also discussed.

19.
Zhonghua Yi Xue Za Zhi ; 100(24): 1890-1894, 2020 Jun 23.
Artigo em Chinês | MEDLINE | ID: mdl-32575934

RESUMO

Objective: To investigate the role of Wnt/ß-catenin/TCF-4 pathway in renal cancer cells and to analyze its possible mechanism. Methods: ß-catenin and TCF-4 were inhibited by siRNA in 786-O cells. The proliferation of transfected cells was detected by CCK8. The cell death of transfected cells was detected by acridine orange -ethidium bromide staining. The expressions of TCF-4, bcl-2, bax and Caspase-3 were detected in transfection group, empty vector group and negative control groups by western blot. Results: The cell proliferation ability of the ß-catenin transfection group was significantly lower than that of the control group (0.443±0.145 vs 0.910±0.721), meanwhile, the cell death rate was significantly increased (16.38±5.32 vs 6.61±1.04), the expression level of Caspase 3 and bax was increased, and the expression of anti-apoptotic protein Bcl-2 was decreased. Decreased TCF-4 led to the same results as inhibition of ß-catenin (all P<0.05). Conclusion: The Wnt/ß-catenin/TCF-4 pathway may play a role in the regulation of proliferation and apoptosis in 786-O renal cancer cells. The mechanism might through regulating of the downstream apoptosis proteins Caspase 3, bax and anti-apoptotic protein Bcl-2.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Via de Sinalização Wnt , beta Catenina
20.
J Contam Hydrol ; 230: 103622, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32044157

RESUMO

During the long term operation of a disposal repository, gas will be inevitably generated. Determination of gas permeability of compacted bentonite is of great importance for the safety assessment of the engineered barrier system. In the present work, the steady-state and residual pressure methods were employed to determine the gas permeability of GaoMiaoZi (GMZ) bentonite with consideration of variations in liquid saturation, dry density and confining pressure. Results show that, gas migration in saturated GMZ bentonite was mainly controlled by diffusion with an effective gas permeability of 1E-23 m2 - 1E-25 m2. While in unsaturated GMZ bentonite, significant gas flow rates could be observed, which increased stably with the increase of gas injection pressure. Klinkenberg effect was significant when gas flow through GMZ bentonite. The Klinkenberg corrected gas permeability decreased by 3.5-5.5 orders of magnitude as the liquid saturation increased from 10% to 70%. A decreasing magnitude of 1-2 orders in Klinkenberg corrected gas permeability was presented with the dry density increased from 1.5 Mg/m3 and 1.7 Mg/m3. The Klinkenberg corrected gas permeability decreased by 0-1 orders of magnitude as the confining pressure increased from 3 MPa to 7 MPa. By using the accessible porosity, gas measured intrinsic permeability could be determined with values ranged between 1E-15 m2 to 4E-15 m2, which was higher than the water measured one by 5 orders of magnitude. Additionally, a generalized power law was successfully adopted in this study to describe the evolution of gas relative permeability with the liquid saturation. Overall, the effective gas permeability, Klinkenberg corrected gas permeability, intrinsic and relative permeability determined in this study provided a comprehensive perspective to assess the buffering property of GMZ bentonite in multi-physical field coupling environment. The parameters obtained can be adopted in further simulation works for long-term safety analysis of the disposal repository from the viewpoint of gas migration.


Assuntos
Bentonita , Resíduos Radioativos/análise , Permeabilidade , Porosidade , Água
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