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71.
人胃癌SGC7901细胞膜钾离子通道的特性   总被引:8,自引:0,他引:8  
目的 研究人胃癌细胞系 SGC790 1细胞膜钾离子通道特性 .方法 以人胃癌细胞系 SGC790 1为研究对象 ,采用穿孔膜片钳全细胞记录法 .结果 人的胃癌 SGC790 1细胞系的静息膜电位为 (- 32 .2± 2 .2 ) m V,在钳制电压 - 40 m V,阶跃电压在 - 80~ +80 m V,记录到一种跨膜电流 ,该跨膜电流具有电压依赖、外向整流特性 ,该电流在延迟 2 5 ms后最大激活 ,80 0 m s内不失活 ,翻转电位在 - 6 0~ - 40 m V,能被已知的钾通道的阻断剂 4- AP或 TEA阻断 .结论 在人胃癌SGC790 1细胞系细胞膜上存在延迟整流钾离子通道 .  相似文献   
72.
目的: 探讨心脏死亡供体(donation after cardiac death,DCD)原位肝移植术后胆道并发症的发生因素、诊断要点和治疗方法。方法: 对2015年1月—2016年8月于南京医科大学第一附属医院肝移植中心实施的87例DCD供肝肝移植患者临床资料进行回顾性分析。87例中29例行经典原位肝移植,58例行改良背驮式肝移植,胆管重建方式均为胆总管端端吻合,无1例放置T管。结果: 87例肝移植患者中9例通过胆道造影确诊为肝移植术后胆道并发症, 8例治愈, 1例好转, 无死亡。胆道并发症发生率10.1%(9/87)。结论: DCD供体原位肝移植术后胆道并发症的发生与供肝缺血时间、DCD供肝质量、胆管吻合技术及供肝修剪技术等因素有关,术后胆道造影有助于及时诊断胆道并发症。介入技术是胆道并发症的主要治疗手段。  相似文献   
73.
PurposeTo assess the feasibility of applying ultra-widefield fundus (UWF) images for macular staphyloma area (MSA) measurement and investigate the associated factors with MSA.MethodsThis is a retrospective study. MSA was measured by UWF imaging. Central foveal thickness, subfoveal choroidal thickness, subfoveal scleral thickness were measured on spectral domain optical coherence tomography. Intraclass correlation coefficients of MSA measurement would be evaluated. Multiple linear regression analysis was used to analyze the associated factors with MSA.ResultsIn total, 135 eyes of 92 patients were enrolled. The mean age was 64.73 ± 10.84 years. Mean MSA on UWF image was 279.67 ± 71.70 mm2. Intraclass correlation coefficients of MSA measurement was 0.965 (95% confidence interval [CI], 0.946 to 0.977; p < 0.001). In the multiple linear regression analysis, after adjusting for subfoveal choroidal thickness, best-corrected visual acuity, central foveal thickness, and subfoveal scleral thickness, the factors independently related to MSA were axial length (β = 8.352; 95% CI, 3.306 to 13.398; p = 0.001), sex (β = −26.673; 95% CI, −51.759 to −1.586; p = 0.037), age (β = 1.184; 95% CI, 0.020 to 2.348; p = 0.046).ConclusionsIt is feasible to measure MSA on UWF image. Female, longer axial length, and older age may indicate larger MSA.  相似文献   
74.
We spectroscopically investigated coordination state of Fe3+ in methanol (MeOH) and ethanol (EtOH) solutions against Cl concentration ([Cl]). In both the system, we observed characteristic absorption bands due to the FeCl4 complex at high-[Cl] region. In the MeOH system, the proportion (r) of [FeCl4] exhibits a stationary value of 0.2–0.3 in the intermediate region of 10 mM < [Cl] < 50 mM, which is interpretted in terms of [FeClnL6−n]3−n (n = 1 and 2). In the EtOH system, r steeply increases from 0.1 at [Cl] = 1.5 mM to 0.7 at [Cl] = 3.5 mM, indicating direct transformation from [FeL6]3+ to [FeCl4]. We further found that the coordination change significantly decreases the redox potential of Fe2+/Fe3+.

Fe3+ coordination in alcohol solution can be controlled by the Cl concentration ([Cl]). The coordination state changes from FeL6 (L: solvent molecule) to FeCl4 type via FeClnL6−n with increases in [Cl].  相似文献   
75.
ContextValerian extract capsule (VEC) is an effective Chinese patent medicine used for gastrointestinal (GI) diseases.ObjectiveTo investigate the detailed pharmacological activity for VEC clinical effects in GI diseases.Materials and methodsSprague-Dawley rats were divided into six groups: control, model, and drug-treated (VEC-L, VEC-M, VEC-H, and teprenone). Rats were orally administered VEC (124, 248, 496 mg/kg) and teprenone (21.43 mg/kg) for 3 consecutive days. After 1 h, the five groups (except the control group) were orally given ethanol (10 mL/kg) for 1 h or indomethacin (80 mg/kg) for 7 h. The spasmolytic activity of VEC (0.01–1 mg/mL) on ACh/BaCl2-induced New Zealand rabbit smooth muscle contraction was performed. The C57BL/6 mice carbon propelling test evaluated the effects of VEC (248–992 mg/kg) on intestinal motility in normal and neostigmine/adrenaline-induced mice.ResultsCompared with the model group, VEC treatment reduced the gastric lesion index and mucosal damage. Further experiments showed that the pathological ameliorative effect of VEC was accompanied by augmentation of the enzymatic antioxidant system and cytoprotective marker (COX-1, p < 0.01; PGI2 p < 0.05;), along with the alleviation of the levels of MPO (ethanol: 15.56 ± 0.82 vs. 12.15 ± 2.60, p < 0.01; indomethacin: 9.65 ± 3.06 vs. 6.36 ± 2.43, p < 0.05), MDA (ethanol: 1.66 ± 0.44 vs. 0.81 ± 0.58, p < 0.01; indomethacin: 1.71 ± 0.87 vs. 1.09 ± 0.43, p < 0.05), and inflammatory mediators. VEC decreased the high tone induced by ACh/BaCl2 and promoted intestinal transit in normal and neostigmine/adrenaline-induced mice.Discussion and conclusionsVEC showed a potential gastroprotective effect, suggesting that VEC is a promising phytomedicine for the treatment of GI diseases.  相似文献   
76.
ObjectiveThis study was performed to examine the relationship between the C-reactive protein/albumin ratio (CAR) and the prognosis of patients with lung adenocarcinoma and thus provide a reference for evaluating the prognosis of lung adenocarcinoma.MethodsThe clinical data of 130 patients with lung adenocarcinoma were retrospectively collected and analyzed. The patients’ overall survival (OS) time was calculated, and the factors affecting OS were statistically analyzed.ResultsThe CAR was correlated with sex, clinical stage, brain metastasis, S100 calcium-binding protein B (S100B), interleukin 17, myelin basic protein, squamous cell carcinoma antigen (SCC-Ag), and the lymphocyte count. The median OS was significantly shorter in the high- than low-CAR group (18 vs. 64 months, respectively). The CAR, clinical stage, brain metastasis, S100B, interleukin 17, SCC-Ag, C-reactive protein, albumin, and neutrophil count affected the OS of patients with lung adenocarcinoma. The CAR and clinical stage were independent risk factors for a poor prognosis in patients with lung adenocarcinoma.ConclusionsThe CAR and clinical stage are independent risk factors for OS in patients with lung adenocarcinoma.  相似文献   
77.
Solid epoxy resin is highly desired in adhesives, electronic materials and coatings due to the attractive characteristics of solvent-free, highly efficient utilization and convenient storage and transportation. However, the challenges remain in fabricating high-toughness solid epoxy resin through a facile and efficient way. Here, a high-performance environment-friendly solid epoxy resin was fabricated by employing maleic anhydride grafted ethylene-vinyl acetate copolymer (EVA-g-MAH) as the flexibilizer via one-step banburying method. The results showed that the modified epoxy resin maintained a high glass transition temperature (Tg) and thermal stability, while its impact strength, tensile toughness and flexural toughness were significantly increased compared with the neat epoxy resin. The impact strength, tensile toughness and flexural toughness of R-EM10 are improved 138%, 195% and 149%, respectively. The EVA-g-MAH was introduced in the epoxy matrix as a separate phase to increase toughness via transfer stress and dissipated energy. The attractive properties of this facile fabrication process and the high-toughness, as well as the environment-friendly performance make this solid epoxy highly promising for large-scale industrial application.

High-toughness and environment-friendly solvent free solid epoxy resin through a low-cost, facile and large-scale fabrication process.  相似文献   
78.
In order to improve the corrosion resistance of the automotive AM60B-Mg alloy, a nano-SiO2/MAO composite coating was prepared on the surface of the alloy. The electrochemical properties were studied in an 80 °C corrosion environment using potentiodynamic polarization tests. Local Electrochemical Impedance Spectroscopy (LEIS) was used to study the corrosion mechanisms of coating defect zone. The microstructure and phase of the samples were observed by confocal laser microscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD). Macroscopic electrochemical test results showed that the impedance of the nano-SiO2/MAO coating was much higher than that of the MAO coating, by about 433 times. Local electrochemical test results showed that the minimum impedance of the nano-SiO2/MAO coating was 1–2 orders of magnitude higher than the maximum impedance of the MAO coating. The defective SiO2/MAO coating still had high corrosion resistance compared to the defective MAO coating. A physical model of local corrosion mechanisms was proposed.  相似文献   
79.
BackgroundPityriasis rosea (PR) is a papulosquamous eruption with generally unknown origin but suspected to be related to viral etiologies. The clinicopathological spectrum of several disorders with viral etiologies has been altered after the coronavirus disease 2019 (COVID-19) pandemic. The author group could experience coherent histological alterations in PR after the COVID-19 pandemic. This study aimed to investigate how the clinicopathological findings of PR were changed after the COVID-19 pandemic.MethodsPatients (n = 11) diagnosed with PR based on the clinical manifestations and skin biopsies between February 2018 and October 2019 and 11 patients in February 2020 and October 2021 were retrospectively analyzed by investigating the medical records.ResultsThe patients with PR during the COVID-19 pandemic demonstrated statistically significant histopathological alterations from classic brisk and dense infiltration pattern to dormant and sparse infiltration and psoriasiform-dominant patterns (P = 0.019). PR was associated with more frequent pruritus during the pandemic period (P = 0.027).ConclusionIn conclusion, PR demonstrated a significant histopathological alteration with more frequent pruritus during the COVID-19 pandemic. The comparative results about clinicopathological findings of PR will provide a useful reference for dermatologists in the diagnostic process of PR in the COVID-19 pandemic.  相似文献   
80.
ObjectiveThis study aims to assess the proportions of complex regional pain syndrome type I (CRPS I) in radial head fracture patients undergoing unilateral arthroplasty and to explore associated factors.MethodsThis is a prospective observational study. From March 2016 to May 2019, a total of 221 adult patients with radial head fracture patients were included in consecutive studies and completed the 1‐year follow‐up. All patients were treated by unilateral arthroplasty. At each follow‐up visit, the visual analogue scale was used to measure patients'' pain level. Occurrence of CRPS I, which was diagnosed by Budapest criteria, was the main outcome collected at baseline and the 1‐, 3‐, 6‐, and 9‐month follow‐ups. The baseline data were collected before surgery and included demographic and clinical data. Independent t‐tests and χ 2 tests were used as univariate analyses to compare the baseline data of patients with and without CRPS I. Multivariate analysis (Backword‐Wald) was used to identify factors independently associated with CRPS I.ResultsThe proportion of CRPS I cases among radial head fracture patients undergoing unilateral arthroplasty was 11% (n = 24). A total of 19 (79%) patients were diagnosed with CRPS I within 1 month after surgery. Multivariable logistic regression analysis revealed that female gender (odds ratios [OR]: 1.537; 95% confidence interval [CI]: 1.138–2.072), age younger than 60 years (OR: 1.682; 95% CI: 1.246–2.267), moderate and severe Mayo Elbow Performance Score (MEPS) pain (OR: 3.229; 95% CI: 2.392–4.351) and anxiety (OR: 83.346; 95% CI: 61.752–112.320) were independently associated with CRPS I.ConclusionsThis exploratory study reported that the incidence of CRPS I developing after radial head arthroplasty was 11%. Female sex, younger age, moderate and severe MEPS pain and anxiety patients seems more likely to develop CRPS I.  相似文献   
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