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51.
The presence of anticardiolipin antibodies (ACLA) in multiple sclerosis (MS) patients has been reported, but there are some debates on the relationship between ACLA and MS. We assessed the clinical features of neuromyelitis optica spectrum disorders (NMOSD) patients with ACLA. A consecutive cohort of 480 subjects with NMOSD (n = 70), MS (n = 90) and control (n = 220) were analysed retrospectively. Patients’ serum was tested by a dot-immunogold filtration assay for the presence of ACLA-IgG, IgM and IgA antibodies. In MS patients, 5 (5.6 %) of the 90 patients showed ACLA-IgG reactivity in the serum. In NMOSD patients, 32 (45.7 %) of the 70 patients showed ACLA reactivity in the serum, among which ACLA-IgG seropositivity was 45.7 % (32/70), ACLA-IgG + IgM seropositivity was 8.6 % (6/70), and ACLA-IgG + IgA seropositivity was 4.3 % (3/70). NMOSD patients were higher in ACLA-IgG (p < 0.0001) and ACLA-IgG + IgM (p = 0.006) than the MS patients. NMOSD patients had higher ACLA-IgG than the control patients (p < 0.0001). In comparison with the controls, the MS patients were lower in ACLA for IgG (p = 0.014) and IgM (p = 0.004). Seropositive ACLA patients increased in age (p = 0.013) and had higher D-dimer levels (DD) (p = 0.002) than the seronegative NMOSD patients. Furthermore, positive ACLA-IgG + IgM patients were increased in age (p = 0.001), had higher baseline EDSS (p = 0.001), antithrombin III activity (p = 0.04), and DD levels (p = 0.005) than the pure positive ACLA-IgG NMOSD patients. Patients with NMOSD had more occurrences of ACLA than patients with MS. NMOSD patients with positive ACLA-IgG + IgM had a worse outcome that may be associated with elder age and abnormal coagulation parameters in blood.  相似文献   
52.
脑胶质瘤病的MRI诊断和MRS分析   总被引:5,自引:0,他引:5  
目的 观察脑胶质瘤病的磁共振表现特点,分析MRS对其诊断、分级、治疗及预后的价值.方法 对12例经手术或活检证实为脑胶质瘤病的患者进行MRI检查,分析病变分布、范围及信号特点;其中5例同时进行MRS检查,包括单体素点解析频谱法以及化学位移成像点解析频谱法,分析代谢物的相对浓度变化.结果 所有患者病变都至少累及2个脑叶,侵及胼胝体9例,基底节区9例,丘脑4例,脑干2例,小脑2例,脊髓1例.病变呈弥漫T1WI低信号、T2WI高信号,信号强度较均匀,少有对比剂增强.5例经MRS检查患者,表现为Cho/Cr,Cho/NAA值的升高,以及不同程度NAA/Cr的降低;3例出现Lactate峰.结论 MRI是脑胶质瘤病的良好检查方法,MRS可提供额外的诊断信息.磁共振成像与MRS结合,有助于诊断治疗,评价手术预后.  相似文献   
53.
Novel series of Farnesylthiosalicylic acid-diamine/phenylpropenoic acid hybrids were designed and synthesized. Their in vitro growth inhibitory assays showed that most compounds displayed strong antiproliferation activity against seven cancer cells. Especially, the new hybrid 12f , by the conjugation of 10a with ferulic acid, could selectively suppress the proliferation of tumor cells and display significantly lower toxicities to normal cells than its intermediate 10a . Furthermore, 12f dose-dependently induced SMMC-7721 cell apoptosis. Additionally, our observations demonstrated that 12f inhibited both Ras-related signaling and phosphorylated NF-κB synergistically, which may be advantageous to the strong antitumor activities of 12f . Our findings suggest that these novel hybrids may hold a great promise as therapeutic agents for the intervention of human cancers.  相似文献   
54.
55.
A new two-dimensional boron–carbon–nitrogen (BCN) structure is predicted and is theoretically investigated based on density functional theory. The BCN structure belongs to the space group C222, and is composed of twelve B, twelve C and twelve N atoms per orthorhombic cell (named oC-B12C12N12). It consists of small hollow spheres with two hexagons per sphere. The dynamical, thermal and mechanical stabilities of oC-B12C12N12 are respectively evaluated by phonon spectroscopy, ab initio molecular dynamics calculations and elastic constant measurements. The simulated in-plane stiffness and Poisson ratio display anisotropic features. The band structure shows that oC-B12C12N12 is a direct semiconductor with a gap of 2.72 eV (GW). oC-B12C12N12 has an absorption range from the visible light spectrum to the ultraviolet. Therefore, due to its small direct band gap and optical absorption, oC-B12C12N12 may be a good candidate for electronic and optical applications.

A predicted 2D BCN structure has a direct band gap and is a good candidate for electronic and optical applications.  相似文献   
56.
目的分析诱发颅内动脉瘤介入术后脑缺血并发症的因素。方法回顾性分析本院2010年1月~2018年12月35例颅内动脉瘤介入术后脑缺血并发症的患者的临床资料,记为A组;另回顾性分析同时间段41例颅内动脉瘤介入术后未并发脑缺血并发症的患者的临床资料,记为B组。归纳脑缺血并发症的可能影响因素,对比A组与B组差异,并进行Logistic多元回归分析。结果两组患者性别、年龄、病程时间、动脉瘤位置、糖尿病史、蛛网膜下腔出血病史、脑梗死或短暂性脑缺血发作病史、饮酒史、颅内血管狭窄、治疗策略、支架类型、Raymond分级相比较,差异无统计学意义(P0. 05),高血压病史、吸烟史、动脉瘤直径和最大径相比较,差异有统计学意义(P 0. 05); Logistic回归分析结果提示,高血压、吸烟、动脉瘤最大径 10 mm为颅内动脉瘤介入术后脑缺血并发症的独立风险因素(P 0. 05)。结论高血压、吸烟、动脉瘤最大径 10 mm为颅内动脉瘤介入术后脑缺血并发症的独立危险因素。  相似文献   
57.
Despite the presence of hepatitis B virus (HBV) in the human breastmilk of mothers infected with HBV, it has been shown that breastfeeding does not increase the risk of mother-to-child transmission (MTCT) of HBV. We tested the hypothesis that human breastmilk may contain active components that bind to HBV and inhibit the infectivity of HBV. The results show that human whey significantly inhibited the binding of the hepatitis B surface antigen (HBsAg) to its antibodies in competitive inhibition immunoassays. The far-western blotting showed that HBsAg bound to a protein of 80 kD in human whey, which was identified as lactoferrin by mass spectrometry. Competitive inhibition immunoassays further demonstrated that both human lactoferrin and bovine lactoferrin bound to HBsAg. Human whey, human lactoferrin, and bovine lactoferrin each significantly inhibited the infectivity of HBV in vitro. Our results indicate that human breastmilk can bind to HBsAg and inhibit the infectivity of HBV, and the active component is lactoferrin. The findings may explain the reason that breastfeeding has no additional risk for MTCT of HBV, although human breastmilk contains HBV. Our study provides experimental evidence that HBV-infected mothers should be encouraged to breastfeed their infants  相似文献   
58.
PurposeThe purpose of this study was to investigate the effects of Forkhead Domain Inhibitor-6 (FDI-6) on regulating inflammatory corneal angiogenesis and subsequent fibrosis induced by alkali burn.MethodsA corneal alkali burn model was established in Sprague Dawley rats using NaOH and the rat eyes were topically treated with FDI-6 (40 µM) or a control vehicle four times daily for 7 days. Corneal neovascularization, inflammation and epithelial defects were observed on days 1, 4, and 7 under a slit lamp microscope after corneal alkali burn. Analysis of angiogenesis-, inflammation-, and fibrosis-related indicators was conducted on day 7. Murine macrophages (RAW264.7 cells) and mouse retinal microvascular endothelial cells (MRMECs) were used to examine the effects of FDI-6 on inflammatory angiogenesis in vitro.ResultsTopical delivery of FDI-6 significantly attenuated alkali burn-induced corneal inflammation, neovascularization, and fibrosis. FDI-6 suppressed the expression of angiogenic factors (vascular epidermal growth factor, CD31, matrix metalloproteinase-9, and endothelial NO synthase), fibrotic factors (α-smooth muscle actin and fibronectin), and pro-inflammatory factor interleukin-6 in alkali-injured corneas. FDI-6 downregulated the expression of monocyte chemotactic protein-1, pro-inflammatory cytokines (interleukin-1β and tumor necrosis factor-alpha), nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3, and vascular endothelial growth factor in RAW264.7 cells and inhibited the proliferation, migration, and tube formation of MRMECs in vitro.ConclusionsFDI-6 can attenuate corneal neovascularization, inflammation, and fibrosis in alkali-injured corneas.  相似文献   
59.
目的探讨小剂量奎的平作为增效剂治疗难治性抑郁症的疗效及安全性。方法26例难治性抑郁症患者在原抗抑郁剂治疗的基础上合用小剂量奎的平。观察时间8周,于治疗前及治疗后1、2、4、8周末采用汉米尔顿抑郁量表、临床总体印象量表—严重程度量表评定疗效,采用副反应量表评定药物不良反应.结果自治疗2周末始,汉米尔顿抑郁量表、临床总体印象量表—严重程度量表评分比治疗前均有减少,差异有显著性。治疗8周末痊愈率11.54%,有效率50.00%,无效率38.46%,不良反应较轻。结论小剂量奎的平可作为增效剂用于难治性抑郁的治疗。  相似文献   
60.
目的:探讨乐肝复方合剂对四氯化碳(CCl4)损伤原代培养大鼠肝细胞的保护作用.方法:以CCl4诱导大鼠肝细胞损伤模型,观察乐肝复方合剂对肝细胞的琥珀酸脱氢酶(SDH)、酸性磷酸酶(ACPase)、葡萄糖-6-磷酸酶(G-6-Pase)活性和糖原含量以及肝细胞形态结构的影响.结果:乐肝复方合剂能显著提高SDH、G-6-Pase活性及糖原含量(P<0.001),显著抑制ACPase活性(P<0.001),并可显著改善受损肝细胞的形态结构变化.结论:乐肝复方合剂对CCl4损伤原代培养大鼠肝细胞具有保护作用.  相似文献   
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