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91.
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93.
Pulmonary surfactant is a surface active material composed of both lipids and proteins that is produced by alveolar type II pneumocytes. Abnormalities of surfactant in the immature lung or in the acutely inflamed mature lung are well described. However, in a variety of subacute diseases of the mature lung, abnormalities of lung surfactant may also be of importance. These diseases include chronic obstructive pulmonary disease, asthma, cystic fibrosis, interstitial lung disease, pneumonia, and alveolar proteinosis. Understanding of the mechanisms that disturb the lung surfactant system may lead to novel rational therapies for these diseases.  相似文献   
94.
Muscarinic antagonists, via muscarinic receptors increase the cAMP/cGMP levels at bovine tracheal smooth muscle (BTSM) through the inhibition of phosphodiesterases (PDEs), displaying a similar behavior of vinpocetine (a specific-PDE1 inhibitor). The presence of PDE1 hydrolyzing both cyclic nucleotides in BTSM strips was revealed. Moreover, a vinpocetine and muscarinic antagonists inhibited PDE1 located at plasma membranes (PM) fractions from BTSM showing such inhibition, an M2AChR pharmacological profile. Therefore, a novel Ca2+/CaM dependent and vinpocetine inhibited PDE1 was purified and characterized at PM fractions from BTSM. This PDE1 activity was removed from PM fractions using a hypotonic buffer and purified some 38 fold using two columns (Q-Sepharose and CaM-agarose). This PDE1 was stimulated by CaM and inhibited by vinpocetine showing two bands in PAGE-SDS (56, 58?kDa) being the 58?kDa identified as PDE1A by Western blotts. This PDE1A activity was assayed with [3H]cGMP and [3H]cAMP exhibiting a higher affinity as Km (μM) for cGMP than cAMP but being close values with Vmax cAMP/cGMP ratio of 1.5. The co-factor Mg2+ showed similar K(A) (mM) for both cyclic nucleotides. Vinpocetine showed similar inhibition concentration 50% (IC50 of 4.9 and 4.6?μM) for cAMP and cGMP, respectively. CaM stimulated the cyclic nucleotides hydrolysis by PDE1A exhibiting similar activation constant as K(CaM), in nM range. The original finding was the identification and purification of a vinpocetine and muscarinic antagonist-inhibited and CaM-activated PM-bound PDE1A, linked to M2AChR. A model of this novel signal transducing cascade for the regulation of cyclic nucleotides levels at BTSM is proposed.  相似文献   
95.
This study reports on the follow-up data of an integrated group program to reduce asthmatic symptoms. The 16 sessions included a comprehensive multibehavioral/desensitization retraining program and utilized EMG/Incentive inspirometer feedback to encourage slow diaphragmatic breathing in all situations. 17 out of 21 volunteers participated in the 15-month follow-up study. At the follow-up all subjects significantly reduced their EMG tension levels while simultaneously increasing their inhalation volumes. Subjects reported reductions in their asthma symptoms, medication use, emergency room visits, and breathless episodes.We thank Ms. Michelle Roland, Kathy Smith, and Jeanne Charbonneau for their helpful assistance.  相似文献   
96.

Purpose

To investigate the effect of Fructus schisandrae syrup on bronchial asthma mice model.

Methods

Sixty Kunming mice were randomly divided into normal control group, bronchial asthma model group, low-, middle-, and high-dose Fructus schisandrae syrup groups. Bronchial asthma was induced by injection of ovalbumin combined smoking. Two hours after the last administration, the change of lung function were observed, the contents of NO, IL-6 in serum were detected, the morphological changes of lung and bronchial were also observed, so as to explore the effect of Fructus schisandrae syrup on bronchial asthma mice.

Results

Compared with model group, the Schisandrae Fructus syrup groups can significantly increase the tidal volume of mice and decrease the respiratory frequency and the degree of bronchial stenosis (P?<?0.01); The Schisandrae Fructus syrup groups can decrease the levels of NO and IL-6 in serum and improve the pathological changes of lung and bronchus in different degrees.

Conclusion

Fructus schisandrae syrup can significantly improve the biochemical indexes and pathological status of mice with bronchial asthma.  相似文献   
97.
Persistent inflammation within the respiratory tract underlies the pathogenesis of numerous chronic pulmonary diseases including chronic obstructive pulmonary disease, asthma and pulmonary fibrosis. Chronic inflammation in the lung may arise from a combination of genetic susceptibility and environmental influences, including exposure to microbes, particles from the atmosphere, irritants, pollutants, allergens, and toxic molecules. To this end, an immediate, strong, and highly regulated inflammatory defense mechanism is needed for the successful maintenance of homeostasis within the respiratory system. Macroautophagy/autophagy plays an essential role in the inflammatory response of the lung to infection and stress. At baseline, autophagy may be critical for inhibiting spontaneous pulmonary inflammation and fundamental for the response of pulmonary leukocytes to infection; however, when not regulated, persistent or inefficient autophagy may be detrimental to lung epithelial cells, promoting lung injury. This perspective will discuss the role of autophagy in driving and regulating inflammatory responses of the lung in chronic lung diseases with a focus on potential avenues for therapeutic targeting.

Abbreviations AR allergic rhinitis

AM alveolar macrophage

ATG autophagy-related

CF cystic fibrosis

CFTR cystic fibrosis transmembrane conductance regulator

COPD chronic obstructive pulmonary disease

CS cigarette smoke

CSE cigarette smoke extract

DC dendritic cell

IH intermittent hypoxia

IPF idiopathic pulmonary fibrosis

ILD interstitial lung disease

MAP1LC3B microtubule associated protein 1 light chain 3 beta

MTB Mycobacterium tuberculosis

MTOR mechanistic target of rapamycin kinase

NET neutrophil extracellular traps

OSA obstructive sleep apnea

PAH pulmonary arterial hypertension

PH pulmonary hypertension

ROS reactive oxygen species

TGFB1 transforming growth factor beta 1

TNF tumor necrosis factor

  相似文献   
98.
目的:研究老年支气管哮喘患者血清25-羟维生素D3[25-(OH)D3]浓度与免疫功能及肺功能的关系。方法:选取2016年1月至2017年12月我院收治的老年支气管哮喘患者96例作为研究组,根据肺功能检查结果分为轻度哮喘组(n=30)、中度哮喘组(n=38)和重度哮喘组(n=28),另选取同期在我院进行体检的健康老年人40例作为对照组。比较各组血清25-(OH)D3浓度、第一秒最大呼气量占用力肺活量百分比(FEV1/FVC)、FEV1占预计值百分比(FEV1%pred)、CD4~+、CD8~+、CD4~+/CD8~+以及血清免疫球蛋白A(IgA)、免疫球蛋白M(IgM)、免疫球蛋白G(IgG)水平,并分析血清25-(OH)D3与免疫功能指标及肺功能指标的相关性。结果:研究组血清25-(OH)D3浓度、FEV1%pred水平均低于对照组(P0.05),两组FEV1/FVC水平比较差异无统计学意义(P0.05)。研究组CD4~+、CD4~+/CD8~+、血清IgA、IgM、IgG水平均低于对照组,CD8~+水平高于对照组(P0.05)。重度哮喘组血清25-(OH)D3、IgA、IgM、IgG水平、FEV1%pred、CD4~+、CD4~+/CD8~+均低于中度哮喘组和轻度哮喘组,中度哮喘组又低于轻度哮喘组(P0.05),重度哮喘组CD8~+水平高于中度哮喘组和轻度哮喘组,中度哮喘组又高于轻度哮喘组(P0.05)。经Pearson相关性分析可得:老年支气管哮喘患者血清25-(OH)D3与FEV1%pred、CD4~+、CD4~+/CD8~+、IgA、IgM、IgG均呈正相关(P0.05),与CD8~+呈负相关(P0.05)。结论:老年支气管哮喘患者的血清25-(OH)D3浓度显著降低,且与肺功能和免疫功能相关,25-(OH)D3浓度的检测可用于评估患者病情严重程度。  相似文献   
99.
目的:探讨不同严重程度支气管哮喘患者血清脂氧素A4(LXA4)水平的表达及临床意义。方法:选取我院2015年10月到2016年11月收治的支气管哮喘患者86例作为研究组,另选同期我院体检结果为健康的40例志愿者纳入正常对照组,根据病情的不同严重程度将研究组分为轻度持续组(26例)、中度持续组(36例)、重度持续组(24例)。比较正常对照组和研究组患者的血清LXA4水平,比较研究组不同严重程度的第1s用力呼气量占预计值的百分比(FEV1%),并分析支气管哮喘患者的LXA4水平与FEV1%的相关性。结果:轻度持续组、中度持续组、重度持续组和正常对照组血清中LXA4水平整体比较差异有统计学意义(P0.05);中度持续组血清中LXA4水平显著高于轻度持续组、重度持续组和正常对照组,重度持续组血清中LXA4水平显著高于轻度持续组和正常对照组,轻度持续组血清中LXA4水平显著高于正常对照组,差异有统计学意义(P0.05);轻度持续组、中度持续组、重度持续组的FEV1%整体比较差异有统计学意义(P0.05);重度持续组的FEV1%显著低于轻度持续组和中度持续组,中度持续组的FEV1%显著低于轻度持续组,差异有统计学意义(P0.05);经Spearman统计分析,支气管哮喘患者的LXA4水平与FEV1%呈明显的负相关(r=-0.486,P=0.041)。结论:LXA4在支气管哮喘中度持续患者血清中表达最高,在轻度持续患者血清中表达最低,支气管哮喘越严重FEV1%水平越低,同时LXA4水平与FEV1%呈明显的负相关。  相似文献   
100.
There was no effective measures can be obtained at present to reverse or prevent airway remodeling. We investigated the therapeutic effect of Erythropoietin (EPO) gene modified mesenchymal stem cells (MSCs) on asthmatic airway remodeling and the possible underlied molecular mechanisms. EPO gene was transfected into MSCs via lentivirus vector. The transfected cells (EPO‐MSCs) were identified by flow cytometry and the EPO secreting function was detected by PCR and Western blot. MSCs or EPO‐MSCs were administrated to albumin (OVA)‐induced chronic asthmatic mouse model via tail veins. The asthmatic phenotype was analyzed. Number of cells in bronchoalveolar lavage fluid (BALF) was counted using a hemocytometer. Histological findings of airways were evaluated by microscopic examination. The concentrations of interleukin 4(IL‐4), interleukin 5(IL‐5), and interleukin 13(IL‐13) in lung homogenate were determined by ELISA. The activation state of transforming growth factor‐β 1 (TGF‐β1), Transforming growth factor beta‐activated kinase 1 (TAK1), and p38 Mitogen Activated Protein Kinase (p38MAPK) signaling was detected by Real‐Time PCR and Western blotting. EPO‐MSCs were successfully constructed. EPO‐MSCs showed a more potently suppressive effect on local asthmatic airway inflammation and the level of IL‐4, IL‐5, and IL‐13 in lung tissue than MSCs. Moreover, the numbers of goblet cells, the thicknesses of smooth muscle layer, collagen density, percentage of proliferating cell nuclear antigen positive (PCNA+) mesenchymal cells, and von Willebrand factor positive(vWF+) vessels were also significantly inhibited by EPO‐MSCs. Furthermore, EPO‐MSCs could downregulate the expression of TGF‐β1, TAK1, and p38MAPK in lung tissue both in mRNA level and in protein level. EPO gene modified MSCs may more efficiently attenuate asthmatic airway remodeling, which maybe related with the downregulation of TGF‐β1‐TAK1‐p38MAPK pathway activity.  相似文献   
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