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排序方式: 共有3127条查询结果,搜索用时 171 毫秒
61.
Hui Chen Guo-Hua Xie Wei-Wei Wang Xiang-Liang Yuan Wen-Ming Xing Hong-Jing Liu Jin Chen Min Dou Li-Song Shen 《Oncotarget》2015,6(24):20449-20465
Axon guidance protein Semaphorin 3E (Sema3E) promotes tumor metastasis and suppresses tumor cell death. Here, we demonstrated that Sema3E was decreased in gastric cancer. Its levels were inversely associated with tumor progression. Levels of Sema3E were associated with low p300 and high class I histone deacetylase (class I HDAC). Ectopic expression of Sema3E inhibited proliferation and colony formation of gastric cancer cell lines in vitro and xenografts in vivo. Sema3E overexpression inhibited migration and invasion of gastric cancer cells, which was associated with induction of E-cadherin and reduction of Akt and ERK1/2 phosphorylation. We suggest that silencing of Sema3E contributes to the pathogenesis of gastric cancer. 相似文献
62.
目的 旨在阐明吻内侧被盖核(rostromedial tegmental nucleus,RMTg)是否参与吗啡引起的大鼠睡眠障碍。方法 将雄性SD大鼠随机分为溶剂对照组和吗啡组,每组7只,对照溶剂为人工脑脊液(artificial cerebrospinal fluid,ACSF)。采用脑立体定位、核团微量注射和睡眠记录与解析等技术观察RMTg内给予吗啡对大鼠睡眠-觉醒周期的影响。结果 与对照组相比,双侧RMTg 给予吗啡(16 mmol/L,每侧0.5 μL)可以引起大鼠长达4 h的觉醒,期间非快动眼(non-rapid eye movement,NREM)睡眠深度降低、快动眼(REM)睡眠减少的现象与吗啡临床用药所引起的睡眠障碍的表现相一致。结论 RMTg参与吗啡引起的大鼠睡眠紊乱。 相似文献
63.
摘 要 目的: 本研究旨在建立肠肽胶囊的质量标准。方法: 采用薄层色谱法鉴别薏苡仁、蒲公英、白芷、厚朴,采用HPLC法测定三七中有效成分三七皂苷R1、人参皂苷Rg1和人参皂苷Rb1的含量。结果: 薄层鉴别斑点清晰,阴性对照无干扰;三七中有效成分三七皂苷R1、人参皂苷Rg1和人参皂苷Rb1分别在40~300 μg·mL-1、320 ~2 400 μg·mL-1、80~600 μg·mL-1范围内线性关系良好;平均加样回收率分别为99.76%、99.33%、99.48%,RSD分别为0.42%、0.48%、0.63%(n=9)。结论:该方法可用于肠肽胶囊的质量控制。 相似文献
64.
65.
The metallic Fe(ii) ion and nonmetallic S codoped g-C3N4 photocatalyst was synthesized through the polymerization of melamine, ferrous chloride and trithiocyanuric acid (TCA) at elevated temperature. The performance of Fe(ii)–S codoped g-C3N4 compounds in RhB photocatalytic degradation was found to increase 5 times. This significant enhancement in catalytic activity is probably related to the enhanced visible light adsorption and the mobility of photoinduced electron/hole pairs, attributable to bandgap narrowing and also lowering in the surface electrostatic potential compared to that of the pure g-C3N4 nanosheets. XRD and XPS results indicate that the Fe species binds with N-atoms to form Fe–N bonds in the state of Fe(ii) ions. Fe(ii) doping increases the specific surface area, and enhances the photoinduced electron/hole pairs illustrated by PL, EIS spectra and transient photocurrent response measurements. The theoretical results show that divalent Fe(ii) ions coordinating in the pore centre among three triazine units form discrete dopant bands and S dopants substituting the N in triazine skeletons excite much stronger delocalized HOMO and LUMO states, facilitating the migration of photogenerated charge carriers, thus enhancing the visible-light driven photocatalytic performance.The photoinduced electrons jump more easily to the conduction band of g-C3N4 for the Fe impurity band locates above the valence band acting a bridge for electron transfer. 相似文献
66.
Yuan Tian Ying Yuan Hang Lu Liang Xu Wei Xian Yang Chao Wei Mu Hai Bo Liu Jue Chen Ke Fei Dou Yi Da Tang Jin Qing Yuan Yong Jian Wu Hong Bing Yan Bo Xu Shu Bin Qiao Yue Jin Yang Run Lin Gao Hong Qiu 《The international journal of cardiovascular imaging》2018,34(9):1331-1337
With the development of coronary angiography for the diagnosis of coronary artery disease, its clinical significance in detecting coronary artery anomalies and evaluating the seriousness is attracting more attention. In the study we aimed to assess the prevalence of anomalous origin of coronary arteries in a Chinese population who underwent coronary angiography for coronary artery disease, and explore any patterns in the common variants and typical anomalies, especially the potentially serious ones. Patients who underwent coronary angiography from January 2013 to December 2016 in Fuwai Hospital were included. Baseline characteristics and angiographic data were collected, the incidence of anomalous origin of coronary arteries was calculated, and the typical patterns were analyzed. Comparisons between the present results and those of existing reports were also conducted. A total of 110,158 patients were included in the study, among which 0.76% (835 cases) had anomalous origin of coronary arteries. Among the anomalies, the incidences of anomalous origin of the right coronary artery (RCA), the left coronary artery (LCA), both the RCA and LCA, single coronary artery (SCA) and dextrocardia were 76.76% (641 cases), 14.61% (122 cases), 1.80% (15 cases), 4.67% (39 cases) and 2.16% (18 cases), respectively. Moreover, 47.54% (397 cases) of the anomalies were shown to be potentially serious, and an RCA arising from the left sinus of Valsalva (LSV) was the most common subtype (39.28%, 328 cases). Although anomalous origin of coronary arteries is not quite common, more clinical attention should be paid to this condition due to the potential risk of serious sequelae. 相似文献
67.
68.
目的:探讨镍钛记忆合金环抱器治疗多发性肋骨骨折的疗效。方法100例多发性肋骨骨折患者均采用镍钛记忆合金环抱器行手术治疗。结果患者均无感染,骨折不愈合及内固定松动、滑脱等并发症发生;术后5个月~12个月取出内固定,骨折部位无炎症反应,心肺功能恢复较好。结论镍钛记忆合金环抱器呈现出良好的组织相容性,手术操作简便、创伤小、并发症少,是一种较为理想的治疗多发性肋骨骨折的方法。 相似文献
69.
目的:研究皮鳞癌1号方对人皮肤鳞状癌A431细胞生长的抑制作用。方法:以0、5、10、20、40、80μg(生药)/ml皮鳞癌1号方分别作用A431细胞24、48、72 h后,测定光密度并计算细胞增殖抑制率以评价其抑制作用;在显微镜下观察细胞形态学变化;光化学法测定乳酸脱氢酶(LDH)的活性;免疫细胞化学法测定B淋巴细胞瘤2(Bcl-2)蛋白、Bcl-2相关X蛋白(Bax)的表达。结果:5、10、20、40、80μg(生药)/ml皮鳞癌1号方对A431细胞均有抑制作用(P<0.01);5、40μg(生药)/ml皮鳞癌1号方可使A431细胞增殖变缓,细胞出现皱缩,与周围细胞黏附力减弱;5、10、20μg(生药)/ml可明显增强A431细胞LDH活性、Bax表达,减弱Bcl-2表达,降低Bcl-2/Bax的比值(P<0.01)。结论:皮鳞癌1号方对A431细胞的增殖具有一定的抑制作用;可能与促进Bax表达、抑制Bcl-2表达、降低Bcl-2/Bax的比值有关。 相似文献
70.
Shan Dongkai Wang Xi Dou Guanhua Zhang Wei Jing Jing He Bai Li Yang Chen Yundai Yang Junjie 《Journal of thrombosis and thrombolysis》2021,51(4):915-923
Journal of Thrombosis and Thrombolysis - The relationship between vascular-specific epicardial adipose tissue (vEAT) volume and myocardial ischemia measured by fractional flow reserve (FFR) was not... 相似文献