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排序方式: 共有1300条查询结果,搜索用时 15 毫秒
1.
文章以云南罗平医院为研究对象,调查了65名一般员工和21名科主任级中层领导,使用PM量表对该医院的高层及中层领导行为进行评估,对情景因素与领导行为的内在联系进行探讨,并提出改进对策。目的是了解员工需求,促进人力资源合理配置,从而提高医院的管理水平。  相似文献   
2.
An autoradiographic method combined with a rosette technique was used to assess the bactericidal activity of individual control and inflammatory peritoneal macrophages (PM phi) in the presence or absence of expression of Fc receptor for IgG (FcR). There was a lack of FcR reactivity in a certain percentage of both categories of PM phi exposed to E. coli X43, a bacterium which is readily phagocytosed in the presence of specific antibody. Both rosetting and non-rosetting PM phi were capable of phagocytosing E. coli X43, but inflammatory PM phi showed a marked reduction in their capacity to ingest these bacteria compared with control PM phi. Once ingested the E. coli X43 were killed equally well by non-rosetting and rosetting control and inflammatory PM phi.  相似文献   
3.
目的:通过应用中医传承辅助平台(V 2.5)挖掘中医药治疗小儿湿疹的组方用药规律,并对高频药物、用药模式及治疗思路进行探讨。方法:搜集国家知识基础设施数据库(CNKI)、中国学术期刊数据库(CSPD)及中文科技期刊数据库(CCD)中2000—2021年应用中医药治疗小儿湿疹的相关文献,经过筛选后建立方药数据库,运用中医传承辅助平台(V 2.5)集成的改进互信息法、关联规则Apriori算法、复杂系统熵聚类与无监督熵聚类等算法对药物频次、性味归经、用药模式、规则分析及新处方等结果进行输出,并进行网络可视化展示。结果:纳入处方200首,共涉及206味中药,高频药物包括甘草、白鲜皮、薏苡仁、茯苓、生地黄、金银花、蝉蜕、地肤子、防风、牡丹皮等,药性以寒性(52.76%)居多,药味以甘(38.89%)、苦(33.37%)、辛(21.96%)味为主,归经以胃经(1 138次)、脾经(1 088次)、肝经(1 061次)居多,并且得到药物之间的关联规则,以及新处方6个。结论:小儿湿疹用药以补虚药、利水渗湿药、清热药、清热解毒药、解表药为主,治疗以疏风清热,燥湿健脾,养血活血为主要大法,分析结果与本病诊疗指南较为吻合,可为小儿湿疹的临床治疗及新药开发提供参考。  相似文献   
4.
Children with chronic renal insufficiency (CRI) secondary to congenital structural abnormalities frequently have significant growth retardation by 2 years of age. In a multicenter placebo-controlled study of the use of recombinant human growth hormone (rhGH), 30 of 125 (24%) participants were<2.5 years of age at enrollment. Since the treatment arms of the study were balanced for age at randomization, data for these patients were examined for efficacy and safety. During the first 2 years of the study, approximately two-thirds of the patients (n=19) received rhGH 0.05 mg/kg per day subcutaneously and one-third (n=11) received placebo injections. At entry into the study, the mean (± SD) calculated creatinine clearance was 29.2±14.3 (range 12.0–63.7) ml/min per 1.73 m2 in the rhGH-treated group and 23.3±15.1 (range 8.0–59.4) ml/min per 1.73 m2 in the placebo-treated group. The 1st year growth rate was 14.1±2.6 cm/year for the rhGH-treated group and 9.3±1.5 cm/year in the placebo-treated group (P<0.00005). During the 2nd year of the study, the growth rate was 8.6±1.2 cm/year in the rhGH-treated group compared with 6.9±1.0 in the placebo groupP=0.025). The height standard deviation score was +2.0±0.7 for the rhGH-treated group compared with –0.2±1.1 in the placebo-treated group (P<0.00005) during the 2 years of the study. Minor adverse events occurred with similar frequency in both groups. These data suggest that rhGH is efficacious and safe in children with CRI under age 2.5 years. rhGH therapy may correct significant loss of growth at this age when used in conjunction with optimal medical management.  相似文献   
5.
目的 通过本研究确定 ,现有除尘设备是否还存在PM2 5复合污染。方法 通过化学、电子显微镜及电子能谱、GC MS等仪器对上述样品多种污染成分及粒径进行定性、定量测定。结果 上述复合污染成分 :水 2 2 % ,有机物 34 75 % ,无机物 4 3 75 %。无机物以Cu、C、Pb、Al为主 ,它们的粒径≤ 1 1μm ,有机污染物14 0多种 ,以酚类及PAHs为主 ,无机物中除铅、砷等重金属 ,还有砷酸、磷酸。结论 在现有除尘设备条件下的冶炼厂烟尘污染为多种重金属、酸性氧化物及几十种有机污染物 (酚类及PAHs)的复合污染 ,它们的粒径分布大多≤ 1 1μm。  相似文献   
6.
Air pollutants of PM2.5 can alter the composition of gut microbiota and lead to inflammation in the lung and gastrointestinal tract. The aim of this study was to evaluate the protective effect of a novel herbal extract blend, FC, composed of Lonicera japonica extract, Momordica grosvenori extract, and broccoli seed extract, on PM2.5-induced inflammation in the respiratory and intestinal tract. A549 cells and THP-1 cells, as well as C57BL/6 mice, were stimulated with PM2.5 to establish in vitro and in vivo exposure models. The models were treated with or without FC. The expression of inflammatory cytokines and tight junction proteins were studied. Proteomic analysis was performed to elucidate mechanisms. Mouse feces were collected for gut microbiota analysis. FC was shown to modulate the upregulation of pro-inflammatory cytokines mRNA expression in A549 and THP-1 cells and downregulated tight junction proteins mRNA expression in A549 cells due to PM2.5 stimulation. In animal models, the decreased expression of the anti-inflammatory factor il-10, tight junction protein ZO-1, and the elevated expression of COX-2 induced by PM2.5 were improved by FC intervention, which may be associated with zo-1 and cox-2 signaling pathways. In addition, FC was shown to improve the gut microbiota by increasing the abundance of beneficial bacteria.  相似文献   
7.
Human cytochrome P450 2C9 (CYP2C9) accounts for ∼20% of hepatic total CYP content and metabolizes ∼15% clinical drugs such as phenytoin, S-warfarin, tolbutamide, losartan, and many nonsteroidal anti-inflammatory agents (NSAIDs). CYP2C9 is highly polymorphic, with at least 33 variants of CYP2C9 (*1B through *34) being identified so far. CYP2C9*2 is frequent among Caucasians with ∼1% of the population being homozygous carriers and 22% are heterozygous. The corresponding figures for the CYP2C9*3 allele are 0.4% and 15%, respectively. There are a number of clinical studies addressing the impact of CYP2C9 polymorphisms on the clearance and/or therapeutic response of therapeutic drugs. These studies have highlighted the importance of the CYP2C9*2 and *3 alleles as a determining factor for drug clearance and drug response. The CYP2C9 polymorphisms are relevant for the efficacy and adverse effects of numerous NSAIDs, sulfonylurea antidiabetic drugs and, most critically, oral anticoagulants belonging to the class of vitamin K epoxide reductase inhibitors. Warfarin has served as a practical example of how pharmacogenetics can be utilized to achieve maximum efficacy and minimum toxicity. For many of these drugs, a clear gene–dose and gene–effect relationship has been observed in patients. In this regard, CYP2C9 alleles can be considered as a useful biomarker in monitoring drug response and adverse effects. Genetic testing of CYP2C9 is expected to play a role in predicting drug clearance and conducting individualized pharmacotherapy. However, prospective clinical studies with large samples are warranted to establish gene–dose and gene–effect relationships for CYP2C9 and its substrate drugs.  相似文献   
8.
Exposure to ambient airborne particulate matter (PM) with an aerodynamic diameter less than 10 μm (PM10) links with public health hazards and increases risk for lung cancer and other diseases. Recent studies have suggested that oxidative stress is a key mechanism underlying the toxic effects of exposure to PM10. Several components of water‐soluble fraction of PM10 (sPM10) have been known to be capable of inducing oxidative stress in in vitro studies. In this study, we investigated if water‐insoluble fraction of PM10 (iPM10) could be also capable of inducing oxidative stress and oxidative damage. Human lung epithelial A549 cells were exposed to 10 μg/mL of sPM10, iPM10 or total PM10 (tPM10) preparation for 24 h. Here, we observed that all three PM10 preparations reduced cell viability and induced apoptotic cell death in A549 cells. We further found that, similar to the exposure to sPM10 and tPM10, the intracellular level of hydrogen peroxide (H2O2) in the iPM10‐exposed cells was increased significantly; meanwhile the activity of catalase was decreased significantly as compared with the unexposed control cells, resulting in significant DNA damage. Our data obtained from inductively coupled plasma‐mass spectrometry (ICP‐MS) assays showed that iron is the most abundant metal in all three PM10 preparations. Thus, we have demonstrated that, similar to sPM10, iPM10 is also capable of inducing oxidative stress by probably inducing generation of H2O2 and impairing enzymatic antioxidant defense, resulting in oxidative DNA damage and even apoptotic cell death through the iron‐catalyzed Fenton reaction. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 226–233, 2014.  相似文献   
9.
10.
PM2.5 travels along the respiratory tract and enters systemic blood circulation. Studies have shown that PM2.5 increases the incidence of various diseases not only in adults but also in newborn infants. It causes chronic inflammation in pregnant women and retards fetal development. In this study, pregnant rats were exposed to PM2.5 for extended periods of time and it was found that PM2.5 exposure increased immune cells in mother rats. In addition, cytokines and free radicals rapidly accumulated in the amniotic fluid and indirectly affected the fetuses. The authors collected cerebral cortex and hippocampus samples at E18 and analyzed changes of miRNA levels. Expression levels of cortical miR‐6315, miR‐3588, and miR‐466b‐5p were upregulated, and positively correlated with the genes Pkn2 (astrocyte migration), Gorab (neuritogenesis), and Mobp (allergic encephalomyelitis). In contrast, PM2.5 decreased expression of miR‐338‐5p and let‐7e‐5p, both related to mental development. Further, PM2.5 exposure increased miR‐3560 and let‐7b‐5p in the hippocampus, two proteins that regulate genes Oxct1 and Lin28b that control ketogenesis and glycosylation, and neural cell differentiation, respectively. miR‐99b‐5p, miR‐92b‐5p, and miR‐99a‐5p were decreased, leading to reduced expression of Kbtbd8 and Adam11 which reduced cell mitosis, migration, and differentiation, and inhibited learning abilities and motor coordination of the fetus. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1412–1425, 2017.  相似文献   
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