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101.
上海市卫生学科带头人的选拔培养和绩效分析 总被引:8,自引:1,他引:8
上海卫生系统选拔 10 2名德才兼备的优秀中青年科技人才进入上海市卫生系统百名跨世纪优秀学科带头人培养计划 ,由市卫生局给予启动基金 ,并与入围者所在单位及其上级主管部门共同制定培养计划 ,签订培养合同 ,落实培养措施 ,对培养对象的实际业务水平、组织管理能力、学术地位、知名度的提高以及医、教、研实际成绩进行全过程的跟踪和考核评估。绩效分析表明 ,通过 5年~ 7年的重点培养和锻炼 ,他们业已成为本市第一代优势学科带头人 ,从整体上推进了上海卫生事业发展和医学水平的提高。 相似文献
102.
目的:探讨外源性给予脑源性神经营养因子前体(brain-derived neurotrophic factor precursor,proBDNF)后脑卒中后抑郁(post-stroke depression,PSD)大鼠额前皮质凋亡信号通路蛋白的表达变化。方法:在55只健康成年雌性SD大鼠中,随机选取25只作为PSD... 相似文献
103.
Effect of Brazilian green propolis on the production of reactive oxygen species by stimulated neutrophils 总被引:3,自引:0,他引:3
Simões LM Gregório LE Da Silva Filho AA de Souza ML Azzolini AE Bastos JK Lucisano-Valim YM 《Journal of ethnopharmacology》2004,94(1):59-65
The activity of a crude ethanol extract of green propolis and its fractions obtained by partition with hexane, chloroform and n-butanol was assessed on luminol- and lucigenin- enhanced chemiluminescence (CL) produced by rabbit neutrophils (PMNs) stimulated with particles of serum-opsonized zymosan (OZ). The total production of reactive oxygen species (ROS) by PMNs was measured by the luminol-enhanced CL (LumCL) assay and the production of the superoxide anion (O2*-) by the lucigenin-enhanced CL (LucCL) assay. All evaluated propolis samples had inhibitory effect on the LumCL and LucCL, which was concentration dependent. The n-butanol and chloroform fractions displayed the highest inhibitory effect on the LumCL produced by PMNs stimulated with OZ, in comparison with both the ethanol extract and the hexane fraction. Besides, the hexane fraction was the one which presented the highest effect for the LucCL assay. Some isolated compounds from both n-butanol and chloroform fractions were also assessed, including kaempferide, isosakuranetin, aromadendrine-4'-methyl-ether and 3-prenyl-p-coumaric acid. Kaempferide presented the highest inhibitory effect on the LumCL in comparison with the other compounds. Moreover, under the conditions assessed, the studied green propolis samples and isolated compounds were not toxic to the rabbit PMNs. 相似文献
104.
探讨老年肾虚证与骨密度的关系 总被引:8,自引:0,他引:8
为探讨老年肾虚证与骨密度的关系 ,通过随机选择 60~ 78岁的肾虚证者 2 1 4例作为观察组 ,并设虚证 (肝肾两虚、肝虚、脾虚证 )组 366例和健康对照组 1 0 0例 ,采用超声成像骨密度测定法 ,测定足跟骨的骨密度。结果 :肾虚证组的骨密度低于正常对照组和肝肾两虚证、肝虚证、脾虚证组 (P <0 0 1 )。提示老年肾虚证与骨密度有直接相应变化的关系 ,骨密度测定可作为肾虚证本质辨证的客观评价指标和观察肾虚证治疗效果的参考依据。 相似文献
105.
目的 评价泛昔洛韦联合α- 1b干扰素治疗慢性乙型肝炎的疗效和安全性。方法 将77例慢性乙型肝炎患者随机分为治疗组和对照组 ,均予一般护肝药物和α - 1b干扰素治疗 ,治疗组加服泛昔洛韦。观察患者血清ALT的变化、HBV -DNA和HBeAg阴转率以及用药后的不良反应。结果 治疗组HBV -DNA ,HBeAg阴转率明显高于对照组 (P <0 .0 1)。治疗组患者除有短期轻度头痛外 ,与对照组相比未见其他不良反应。结论 泛昔洛韦联合干扰素治疗慢性乙型肝炎疗效好且安全性高 相似文献
106.
Aquaporin-4 gene disruption in mice protects against impaired retinal function and cell death after ischemia 总被引:8,自引:0,他引:8
PURPOSE: Water channel aquaporin (AQP)-4 is expressed in Muller cells in retina, which are similar to astroglial cells in the central nervous system, where AQP4 deletion protects against cytotoxic brain edema after cerebral ischemia. A transient ischemia-reperfusion model was used to determine whether AQP4 deletion in mice protects the retina. METHODS: Retinal function and morphology were assessed in wild-type versus AQP4-deficient mice after ischemic damage produced by a 45- to 60-minute elevation of intraocular pressure to 120 mm Hg. Retinal function was assessed by electroretinography, and retinal structure by light microscopy. Extracellular space (ECS) size in fluorescently stained retinal slices was assessed by fluorescence recovery after photobleaching. RESULTS: Retinal function and cell survival were significantly improved in AQP4-deficient mice in both inbred (C57/bl6) and outbred (CD1) genetic backgrounds. By electroretinography, b-wave amplitude was reduced by 75% to 83% at 1 to 4 days after ischemia in wild-type mice versus 48% to 51% in AQP4-null CD1 mice. Reductions were 53% to 72% versus <34% in C57/bl6 mice. Retinal structure and cell count were preserved in AQP4-null mice, particularly in the inner nuclear and plexiform layers of the retina, where Müller cells are concentrated. At 4 days after ischemia, inner retinal thickness was thinned by 43% in wild-type mice versus 11% in AQP4-null mice. Several mechanisms for retinal protection were investigated, including ECS expansion, reduced early swelling, and altered Kir4.1 K(+) channel expression. CONCLUSIONS: AQP4 deletion in mice is neuroprotective in a transient ischemia model of retinal injury, suggesting the possible use of AQP4 inhibitors in retinal vascular occlusive and ischemic diseases. 相似文献
107.
牡丹皮中丹皮酚、总苷、多糖单用及合用后的协同抑菌作用考查 总被引:6,自引:0,他引:6
目的:考查牡丹皮中抑菌药效成分丹皮酚、总苷、多糖单用及合用后的协同抑菌作用.方法:分别提取牡丹皮中的丹皮酚、总苷、多糖,定量后再以大肠埃希菌、肺炎克雷白菌、铜绿假单胞菌、粪肠球菌为实验菌株,用琼脂二倍稀释法测定最小抑菌浓度(MIC,minimal inhibitory concentrations),并分析比较抑菌活性.结果:牡丹皮总苷对大肠埃希菌、肺炎克雷白菌、铜绿假单胞菌、粪肠球菌标准株和临床株均有抑菌作用,其中对铜绿假单胞菌作用最强,对肺炎克雷白菌作用相对较弱;丹皮酚与总苷相比也具有抑菌作用,MIC明显高于总苷;多糖仅对粪肠球菌及铜绿假单胞菌有抑菌效果;丹皮酚与总苷合用后有协同抑菌作用,对粪肠球菌尤为显著.结论:牡丹皮总苷及丹皮酚具有一定的抑菌活性,且二者合用效果更强,提示该作用可进一步开发利用. 相似文献
108.
Chun‐Liang Tung Da‐Tong Ju Bharath Kumar Velmurugan Bo Ban Tran D. Dung Dennis J.‐Y. Hsieh Vijaya P. Viswanadha Cecilia H. Day Yueh‐Min Lin Chih‐Yang Huang 《Environmental toxicology》2019,34(12):1320-1328
Carthamus tinctorius L. (Compositae) is used in Chinese medicine to treat heart disease and inflammation. In our previous study, we found that C. tinctorius L. inhibited lipopolysaccharides (LPS)‐induced tumor necrosis factor‐alpha (TNF‐α) activation, JNK expression, and apoptosis in H9c2 cardiomyoblast cells. The present study was performed to investigate the protective effect of C. tinctorius extract (CTF) on LPS‐challenged H9c2 myocardioblast cell and to explore the possible underlying mechanism. Cell viability assay showed that LPS treatment decreased the cell viability of H9c2 cell, whereas CTF treatment reversed LPS cytotoxicity in a dose‐dependent manner, especially in the LPS + CTF 25 (μg/mL) group. LPS treatment‐induced apoptosis was determined by transferase‐mediated dUTP nick end labeling assay, and by Western blot. LPS‐induced apoptotic bodies were decreased following CTF treatment. Expression of TNF‐α, FAS‐L, FAS, FADD, caspase‐8, BID, and t‐BID was significantly increased in LPS‐treated H9c2 cells. In contrast, it was significantly suppressed by the administration of CTF extract. In addition, CTF treatment activates antiapoptotic proteins, Bcl‐2 and p‐Bad, and downregulates Bax, cytochrome‐c, caspase‐9, caspase‐3, and apoptosis‐inducing factor expression. Furthermore, CTF exerted cytoprotective effects by activating insulin‐like growth factor‐I (IGF‐I) signaling pathway leading to downregulation of the apoptotic proteins involved in FAS death receptor pathway. In addition, AG1024 and IGF‐I receptor (IGF‐IR) inhibitor and siRNA silencing reverses the effect of CTF implying that CTF functions through the IGF‐IR pathway to inhibit LPS‐induced H9c2 apoptosis. These results suggest that treatment with CTF extract prevented the LPS‐induced apoptotic response through IGF‐I pathway. 相似文献
109.
Microstructure and Friction Properties of CoCrFeMnNiTix High-Entropy Alloy Coating by Laser Cladding
Pengfei Liu Wudong Si Dabin Zhang Sichao Dai Benchi Jiang Da Shu Lulu Wu Chao Zhang Meisong Zhang 《Materials》2022,15(13)
To enhance the friction and wear properties of 40Cr steel’s surface, CoCrFeMnNi high-entropy alloy (HEA) coatings with various Ti contents were prepared using laser cladding. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) were used to characterize the phase composition, microstructure, and chemical composition of the samples. The findings demonstrated that the CoCrFeMnNiTix HEA coatings formed a single FCC phase. Fe2Ti, Ni3Ti, and Co2Ti intermetallic compounds were discovered in the coatings when the molar ratio of Ti content was greater than 0.5. The EDS findings indicated that Cr and Co/Ni/Ti were primarily enriched in the dendrite and interdendrite, respectively. Ti addition can effectively enhance the coating’s mechanical properties. The hardness test findings showed that when the molar ratio of Ti was 0.75, the coating’s microhardness was 511 HV0.5, which was 1.9 times the hardness of the 40Cr (256 HV0.5) substrate and 1.46 times the hardness of the CrCrFeMnNi HEA coating (348 HV0.5). The friction and wear findings demonstrated that the addition of Ti can substantially reduce the coating’s friction coefficient and wear rate. The coating’s wear resistance was the best when the molar ratio of Ti was 0.75, the friction coefficient was 0.296, and the wear amount was 0.001 g. SEM and 3D morphology test results demonstrated that the coating’s wear mechanism changed from adhesive wear and abrasive wear to fatigue wear and abrasive wear with the increase in Ti content. 相似文献
110.