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21.
Repurposing of the anthelminthic drug niclosamide was proposed as an effective treatment for inflammatory airway diseases such as asthma, cystic fibrosis, and chronic obstructive pulmonary disease. Niclosamide may also be effective for the treatment of viral respiratory infections, such as SARS-CoV-2, respiratory syncytial virus, and influenza. While systemic application of niclosamide may lead to unwanted side effects, local administration via aerosol may circumvent these problems, particularly when the drug is encapsulated into small polyethylene glycol (PEG) hydrospheres. In the present study, we examined whether PEG-encapsulated niclosamide inhibits the production of mucus and affects the pro-inflammatory mediator CLCA1 in mouse airways in vivo, while effects on mucociliary clearance were assessed in excised mouse tracheas. The potential of encapsulated niclosamide to inhibit TMEM16A whole-cell Cl currents and intracellular Ca2+ signalling was assessed in airway epithelial cells in vitro. We achieved encapsulation of niclosamide in PEG-microspheres and PEG-nanospheres (Niclo-spheres). When applied to asthmatic mice via intratracheal instillation, Niclo-spheres strongly attenuated overproduction of mucus, inhibited secretion of the major proinflammatory mediator CLCA1, and improved mucociliary clearance in tracheas ex vivo. These effects were comparable for niclosamide encapsulated in PEG-nanospheres and PEG-microspheres. Niclo-spheres inhibited the Ca2+ activated Cl channel TMEM16A and attenuated mucus production in CFBE and Calu-3 human airway epithelial cells. Both inhibitory effects were explained by a pronounced inhibition of intracellular Ca2+ signals. The data indicate that poorly dissolvable compounds such as niclosamide can be encapsulated in PEG-microspheres/nanospheres and deposited locally on the airway epithelium as encapsulated drugs, which may be advantageous over systemic application.  相似文献   
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Asthma and obesity are considered as highly prevalent diseases with a great impact on public health. Obesity has been demonstrated to be an aggravating factor in the pathogenesis of asthma. Adipose tissue secretes proinflammatory cytokines and mediators, including leptin, which may promote the development and severity of asthma in obese patients. This study is a systematic review and a meta-analysis based on the relationship between leptin and asthma during obesity. MEDLINE, Cochrane, EMBASE and CINAHL databases were used. Data heterogeneity was analyzed using Cochran’s Q and treatment effect with the DerSimonian and Laird method. Random effect analyses were carried out to test data sensitivity. Asymmetry was estimated using Begg’s and Egger’s tests. All studies showed significant differences in leptin levels. The effect of the measures (p < 0.001), data sensitivity (p < 0.05) and data asymmetry were statistically significant, as well as tBegg’s test (p = 0.010) and Egge’s test (p < 0.001). Despite the existing limiting factors, the results of this study support the relevant role of leptin in the pathophysiology of asthma in obese subjects. Nevertheless, further studies are needed to obtain better insight in the relationship between leptin and asthma in obesity.  相似文献   
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Background: mast cells play an important role in airway inflammation in asthma. The transient receptor potential melastatin-like 7 (TRPM7) channel is expressed in primary human lung mast cells and plays a critical role for cell survival. This study aimed to investigate the role of TRPM7 on degranulation and release of cytokines in rat bone marrow-derived mast cells (BMMCs). Methods: the expression levels of TRPM7 were observed by immunocytochemistry and RT-PCR between normal and asthmatic rat BMMCs. TRPM7-specific shRNA and 2-aminoethoxydiphenyl borate (2-APB) and specific shTRPM7 were used to inhibit the function of TRPM7. Degranulation levels were analyzed by beta-hexosaminidase assay. Histamine, TNF-α, IL-6 and IL-13 levels were measured by ELISA. Results: the expression of TRPM7 was significantly higher in asthmatic rat BMMCs than in the normal control group. After application of 2-APB and down-regulation of TRPM7, the beta-hexosaminidase activity and secretion of histamine, IL-6, IL-13 and TNF-α were significantly decreased in the asthmatic group compared to the control group. Conclusion: this study indicates that TRPM7 channels may be involved in the process of degranulation and release of cytokines in rat bone marrow-derived mast cells.  相似文献   
25.
Adenosine is a nucleoside involved in the pathogenesis of allergic diseases. Its effects are mediated through its binding to G protein-coupled receptors: A1, A2a, A2b and A3. The receptors differ in the type of G protein they recruit, in the effect on adenylyl cyclase (AC) activity and the downstream signaling pathway triggered. Adenosine can produce both an enhancement and an inhibition of mast cell degranulation, indicating that adenosine effects on these receptors is controversial and remains to be clarified. Depending on the study model, A1, A2b, and A3 receptors have shown anti- or pro-inflammatory activity. However, most studies reported an anti-inflammatory activity of A2a receptor. The precise knowledge of the adenosine mechanism of action may allow to develop more efficient therapies for allergic diseases by using selective agonist and antagonist against specific receptor subtypes.  相似文献   
26.
The concept of united airway diseases (UAD) has received increasing attention in recent years. Sustained and increased inflammation is a common feature of UAD, which is inevitably accompanied with marked gene modification and tight gene regulation. However, gene regulation in the common inflammatory processes in UAD remains unclear. MicroRNA (miRNA), a novel regulator of gene expression, has been considered to be involved in many inflammatory diseases. Although there are an increasing number of studies of miRNAs in inflammatory upper and lower airway diseases, few miRNAs have been identified that directly link the upper and lower airways. In this article, therefore, we reviewed the relevant studies available in order to improve the understanding of the roles of miRNAs in the interaction and pathogenesis of UAD.  相似文献   
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Macrophages act as immune scavengers and are important cell types in the homeostasis of various tissues. Given the multiple roles of macrophages, these cells can also be found as tissue resident macrophages tightly integrated into a variety of tissues in which they fulfill crucial and organ-specific functions. The lung harbors at least two macrophage populations: interstitial and alveolar macrophages, which occupy different niches and functions. In this review, we provide the latest insights into the multiple roles of alveolar macrophages while unraveling the distinct factors which can influence the ontogeny and function of these cells. Furthermore, we will highlight pulmonary diseases, which are associated with dysfunctional macrophages, concentrating on congenital diseases as well as pulmonary infections and impairment of immunological pathways. Moreover, we will provide an overview about different treatment approaches targeting macrophage dysfunction. Improved knowledge of the role of macrophages in the onset of pulmonary diseases may provide the basis for new pharmacological and/or cell-based immunotherapies and will extend our understanding to other macrophage-related disorders.  相似文献   
29.
近年来儿童哮喘和过敏性疾病患病率呈明显上升趋势,其生活和学习场所空气品质与哮喘和呼吸道疾病密切相关,检测分析室内污染物水平变得十分迫切.为了确定严寒地区与儿童哮喘和过敏性疾病相关的主要室内污染物浓度水平以及不同污染物之间的相关性,对哈尔滨地区10岁左右儿童的健康状态及居住环境进行问卷调查,并选取病例组和对照组进行现场检测以及对比分析.问卷调查结果显示:室内潮湿、结露、发霉、有可见水流、装修以及室内人员吸烟等都与儿童哮喘和过敏性疾病密切相关.选取10户住宅(6户病例组和4户对照组)和2间教室现场监测温湿度、颗粒物质量浓度,采集空气中总挥发性有机物(TVOCs)和半挥发性有机物(SVOCs),计算浮游真菌、堆积真菌以及附着真菌菌落数.分析病例组和对照组测试参数差异性,以及采样点不同参数之间的相关性.结果表明:高温干燥的环境可能会导致儿童患哮喘和呼吸道疾病;病例组和对照组PM2.5质量浓度统计学差异不显著(P=0.157);儿童患有呼吸过敏性疾病与降尘中SVOCs浓度有关;客厅和儿童卧室浮游真菌显著相关(r=0.943,P=0.005),附着真菌也有相同的结果(r=0.943,P=0.005).  相似文献   
30.
Children with asthma are at increased risk for waking in the night, and there is the potential for the entire household to feel the effects. The authors conducted a telephone-based diary study to examine whether daily fluctuations in parent mood, parenting hassles, and family routines would distinguish nights in which waking occurred from nights in which they did not. Forty-seven families with a child with asthma were contacted 4 times a week every 3 months over a period of 1 year, resulting in 500 daily observations. Parent negative mood, perceived parenting hassles, and disruptions in bedtime routines were associated with increased odds that the child would wake in the middle of the night. Results underscore the importance of considering family climate in children's disturbed sleep. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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