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971.
Yun-Lian Lin Guei-Jane Wang Chuen-Lin Huang Yi-Chao Lee Wei-Chen Liao Wen-Lin Lai Yen-Ju Lin Nai-Kuei Huang 《Journal of ethnopharmacology》2009
Ethnopharmacological relevance
Ligusticum chuanxiong (LC) as a common component in many traditional Chinese medicinal formulas and decoctions has been used to treat different central nervous diseases, suggesting a neuroprotective function.Aim of the study
To investigate the functional roles of mitogen-activated protein kinases (MAPKs) in mediating the neuroprotection of LC.Materials and methods
Different extractions of LC were applied with or without MAPK inhibitor to test their protection against serum deprivation-induced apoptosis in rat neuronal-like pheochromocytoma (PC12) cells as revealed by an MTT assay or Hoechst staining. Western blot was used to identify the activations of MAPKs.Results
The most effective butanol extraction (LC-BuOH) was used in the following experiments. LC-BuOH reversed serum deprivation-induced decreased phosphorylation of extracellular signal-regulated kinase (ERK) and increased phosphorylation of c-Jun NH2-terminal kinase (JNK) and p38, the family of MAPKs. A PKA inhibitor, blocked the protection of LC-BuOH and partially blocked LC-BuOH-induced alterations in MAPKs, suggesting that the LC-BuOH regulates MAPKs through both PKA-dependent and -independent pathways. Although PD 98059, an inhibitor of MEK which activates ERK, blocked LC-BuOH-induced ERK phosphorylation, it did not block the protection of LC-BuOH.Conclusions
LC-BuOH mediates protection by suppressing JNK/p38 instead of activating ERK activity. 相似文献972.
Ho-Ming Su Wen-Hsien Lee Wei-Chung Tsai Tzu-Chieh Lin Ye-Hsu Lu Chee-Siong Lee Tsung-Hsien Lin Wen-Chol Voon Wen-Ter Lai Sheng-Hsiung Sheu Po-Chao Hsu 《Journal of atherosclerosis and thrombosis》2022,29(3):337
Aim: Abnormal ankle-brachial index (ABI) is regarded as peripheral artery disease and can be used to predict cardiovascular (CV) outcomes. However, the usefulness of ABI for the prediction of CV outcome in patients with normal ABI is limited. Upstroke time per cardiac cycle (UTCC) is recently reported to be associated with mortality in patients with acute myocardial infarction and the elderly. Therefore, we aimed to evaluate UTCC, left ventricular ejection fraction (LVEF), brachial-ankle pulse wave velocity (baPWV), and ABI for the prediction of mortality in patients with normal ABI. Methods: Patients arranged for echocardiographic examinations were enrolled, and 1076 patients with normal ABI were included. ABI, baPWV, and UTCC were measured by an ABI-form device. Results: The median follow-up to mortality was 95 months. There were 88 CV and 244 all-cause deaths. After multivariate analysis, UTCC was associated with increased CV and all-cause mortality ( P ≤ 0.004). Age, diabetes, heart failure, left ventricular hypertrophy, baPWV, and LVEF were also independent predictors of CV and all-cause mortality, but ABI was not. Furthermore, UTCC had a better additive predictive value than ABI, baPWV, and LVEF for CV mortality ( P ≤ 0.012). It also had a better additive predictive value than ABI and LVEF for all-cause mortality ( P ≤ 0.013). Conclusions: UTCC is an independent predictor for CV and all-cause mortality in patients with normal ABI. It also has a better additive predictive value of CV and all-cause mortality than ABI and LVEF. Therefore, UTCC is a simple, novel, and useful parameter for identifying high-risk patients with normal ABI. 相似文献
973.
Gluskin E Randall KJ McNulty I Yun W Khounsary AM Lai B 《Journal of X-ray science and technology》1995,5(1):29-42
Knowledge of the intermediate energy range from 0.5-4 keV, bridging the "soft" and "hard" x-ray regions, is relatively underdeveloped. However, recent developments in the techniques of microscopy and magnetic circular dichroism have emphasized the need to operate in this energy range for microelectronic, biological, and materials science related experiments. The strong dipole-allowed 3d to 4f transitions in rare-earth magnetic materials fall in this region, as do the K-shells of many of the second and third row elements of the periodic table. Two beamlines to be constructed at the Advanced Photon Source (APS) have been designed to cover this energy region. The proposed undulator source, the beamline layout, and the experimental programs for these beamlines are described. 相似文献
974.
Debra Pugh Andre De Champlain Mark Gierl Hollis Lai Claire Touchie 《Medical teacher》2016,38(8):838-843
With the recent interest in competency-based education, educators are being challenged to develop more assessment opportunities. As such, there is increased demand for exam content development, which can be a very labor-intense process. An innovative solution to this challenge has been the use of automatic item generation (AIG) to develop multiple-choice questions (MCQs). In AIG, computer technology is used to generate test items from cognitive models (i.e. representations of the knowledge and skills that are required to solve a problem). The main advantage yielded by AIG is the efficiency in generating items. Although technology for AIG relies on a linear programming approach, the same principles can also be used to improve traditional committee-based processes used in the development of MCQs. Using this approach, content experts deconstruct their clinical reasoning process to develop a cognitive model which, in turn, is used to create MCQs. This approach is appealing because it: (1) is efficient; (2) has been shown to produce items with psychometric properties comparable to those generated using a traditional approach; and (3) can be used to assess higher order skills (i.e. application of knowledge). The purpose of this article is to provide a novel framework for the development of high-quality MCQs using cognitive models. 相似文献
975.
大肠侧向发育型肿瘤细胞株的建立及其鉴定 总被引:9,自引:4,他引:9
目的 为了深入研究大肠侧向发育型肿瘤(LST)细胞的生物学特性及其发生发展的机制。方法采用人LST组织进行肿瘤细胞建株及细胞分离与原代培养,传代至70代进行细胞鉴定.包括细胞的形态结构分析、染色体分析和免疫组化分析等,并与非LST细胞作对比。结果 LST细胞为上皮来源的肿瘤细胞,多形性上皮细胞占大多数,其有近似肿瘤细胞的生长特性,群体倍增时间为36h;染色体数量为42-66,85%在三倍体范围内,并具有异常染色体核型;免疫组织化学观察ESA、CK20均呈阳性;超微结构具肿瘤细胞样表现和特征。结论成功建立了1个LST细胞株,并命名为LST-R1细胞,为进一步深入研究LST细胞的生物学特性及大肠癌的发生发展机制奠定了基础。 相似文献
976.
目的:探讨维甲酸对单侧输尿管梗阻(UUO)大鼠肾小管间质损害的保护作用.方法:成年清洁级雄性SD大鼠45只,随机分为假手术组(S组)、UUO组(U组)和治疗组(T组),每组15只.假手术组行左输尿管游离,不结扎;UUO组和治疗组行左输尿管结扎.治疗组术后每天给予5 mg/kg全反式维甲酸(ATRA)皮下注射,假手术组和UUO组注射同体积溶剂.于术后第3、7、14 d观察肾小管损害、肾间质炎性细胞浸润程度,免疫组化法观察病变肾组织趋化因子RANTES和TGF-β1表达.结果:与UUO组相比,治疗组肾间质炎性细胞浸润和肾小管损害程度显著减轻(P<0.01),肾组织RANTES和TGF-β1表达显著降低(P<0.01~0.05).结论:维甲酸能减少UUO大鼠肾间质炎性细胞浸润,减轻肾小管损害,抑制RANTES和TGF-β1表达,从而减轻肾脏炎症反应和纤维化. 相似文献
977.
目的 调查分析全国首台AP1000核电机组安装后周围生活饮用水中90Sr和137Cs及食品中137Cs放射性水平及变化。方法 2012—2019年,选取全国首台AP1000核电机组所在的三门核电站周围的4个生活饮用水监测点,分别在丰水期和枯水期采集并测定90Sr和137Cs放射性活度浓度;采集当地产大米、包菜、鲫鱼和鲻鱼,测定分析137Cs放射性活度浓度。结果 2012—2019年,生活饮用水中90Sr和137Cs放射性活度浓度范围分别为1.2~9.8、0.2~8.1 mBq/L;食品中137Cs放射性活度浓度为1.1×10-2~2.8×10-1 Bq/kg,小于《食品中放射性物质限制浓度标准》(GB 14882-94)限制浓度。结论 全国首台AP1000核电机组安装后周围生活饮用水中90Sr和137Cs及食品中137Cs放射性水平平稳,调查数据显示未发现对环境带来影响。 相似文献
978.
目的对自闭症病人给予被动性语言刺激,评价采用功能性磁共振(MR)成像作为判断病人有无语言缺陷的客观指标的可行性。材料与方法本研究为前瞻性研究,研究方 相似文献
979.
Brain abscess and necrotic brain tumor: discrimination with proton MR spectroscopy and diffusion-weighted imaging 总被引:15,自引:0,他引:15
Lai PH Ho JT Chen WL Hsu SS Wang JS Pan HB Yang CF 《AJNR. American journal of neuroradiology》2002,23(8):1369-1377
BACKGROUND AND PURPOSE: Discriminating pyogenic brain abscesses from cystic or necrotic tumors is sometimes difficult with CT or MR imaging. We compared findings of proton MR spectroscopy ((1)H-MRS) with those of diffusion-weighted imaging to determine which technique was more effective for this differential diagnosis. METHODS: Fourteen patients (necrotic or cystic tumor [n = 7]; pyogenic abscess [n = 7]) who underwent 1.5-T (1)H-MRS and diffusion-weighted imaging and had findings of ring-shaped enhancement after contrast agent administration were enrolled in this study. Diffusion-weighted imaging was performed with a single-shot spin-echo echo-planar pulse sequence (b = 1000 s/mm(2)). The apparent diffusion coefficient and ratio were also measured. RESULTS: Spectra for two patients were unacceptable because of either poor shimming conditions or contamination from neighboring fat. Spectra in three of five patients with abscess had lactate, amino acids (including valine, alanine, and leucine), and acetate peaks; one of the three spectra had an additional peak of succinate. In one patient with abscess treated by antibiotics, only lactate and lipid peaks were detected. Spectra for four of seven patients with cystic or necrotic tumors showed only lactate peaks. Lactate and lipids were found in three patients with tumors. Hyperintensity was seen in all the pyogenic abscess cavities and hypointensity in all the cystic and necrotic tumors on diffusion-weighted images. CONCLUSION: (1)H-MRS and diffusion-weighted imaging are useful for differentiating brain abscess from brain tumor, but the latter requires less time and is more accurate than is (1)H-MRS. (1)H-MRS is probably more limited in cases of smaller peripheral lesions, skull base lesions, and treated abscesses. 相似文献
980.