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71.
目的:探讨了妊高征患者血清瘦素水平与外周血B细胞和T细胞亚群水平的变化及临床意义.方法:采用放射免疫分析和单克隆抗体法对32例妊高征患者进行了血清瘦素水平和外周血B细胞及T细胞水平检测,并与35名正常妊娠妇女作比较.结果:妊高征患者血清瘦素、B细胞数均非常显著地高于正常人组(P<0.01).血CD3、CD4/CD8则显著地低于正常人组(P<0.01).结论:检测妊高征患者血清瘦素水平以及外周血B细胞和T细胞亚群水平的变化在一定程度上反映了机体的免疫功能状态,具有一定的临床实用价值.  相似文献   
72.
通痹灵对于IL-2及其受体α链影响的体内外研究   总被引:6,自引:0,他引:6  
从体内体外两个方面 ,研究通痹灵对于CIA大鼠关节滑膜原代细胞分泌IL 2 ,以及通痹灵总碱对于IL 2受体α链CD2 5表达的影响。体内实验采用CIA大鼠动物模型。容积法测量足肿胀度 ,原代滑膜细胞培养、放免法检测培养液上清 ,观察通痹灵对滑膜内IL 2的影响 ;体外实验 ,分离大鼠淋巴细胞 ,佛波醇酯 (PDB )或刀豆蛋白 (ConA )体外刺激 ,双色免疫荧光标记 ,流式细胞仪检测 ,观察通痹灵总碱对CD3+CD2 5 +表达的影响。结果是体内实验 ,通痹灵高剂量可明显减轻CIA大鼠的足肿胀度 ,与MTX比较无显著性差异 (P >0 0 5 ) ,通痹灵高、低剂量可明显抑制CIA大鼠滑膜内IL 2的合成 (P <0 0 1) ;体外实验 ,通痹灵总碱显著抑制ConA刺激下的CD3+CD2 5 +的表达 ,而对PDB加ionomycin没有明显作用。提示通痹灵可以通过抑制IL 2合成及ConA激活的IL 2受体α链CD2 5信号转导通路 ,减轻局部关节的炎症 ,为其用于类风湿性关节炎的治疗提供了实验依据  相似文献   
73.
Pharmacokinetics of a novel oral slow-release form of misoprostol   总被引:1,自引:0,他引:1  
BACKGROUND: The pharmacokinetics of a novel slow-release (SR) misoprostol was studied and compared to conventional misoprostol. METHODS: Thirty-one women, pregnant between 8 and 12 weeks, requesting surgical abortion were randomly allocated to receive orally 400 microg conventional misoprostol, 400 microg SR misoprostol or 800 microg SR misoprostol. Venous blood samples were taken at 0, 30, 60, 120, 240 and 360 min after the administration of misoprostol. Misoprostol acid (MPA) was determined in serum samples using liquid chromatography/tandem mass spectrometry. RESULTS: Serum peak concentration (Cmax) was highest for conventional oral misoprostol. The time to peak concentration (Tmax) was similar for all groups. The area under the curve up to 360 min was similar for conventional and for 800 microg SR misoprostol and significantly greater for these groups compared to 400 microg SR misoprostol (P = 0.013). CONCLUSION: The new SR form of misoprostol demonstrated lower peak levels but longer-lasting elevation in plasma levels compared to conventional oral misoprostol. The AUC for 800 microg SR misoprostol was similar to that of 400 microg of conventional oral misoprostol. SR misoprostol may offer an alternative to repeated administration of oral misoprostol or to vaginal administration.  相似文献   
74.
The inflammatory process in chronic obstructive pulmonary disease (COPD) is active mainly in the airways, but little is known about the properties of the inflammatory cells in this compartment. We have studied leucocytes in induced sputum of COPD patients compared to controls in order to uncover what types of macrophages might be involved in the disease. Sputum induction was performed by inhalation of nebulized sodium chloride solution. Leucocytes were isolated and stained with specific monoclonal antibodies for analysis in flow cytometry. Flow cytometry analysis revealed that a major portion of CD14+ macrophages in COPD has lower forward scatter, i.e. they are small macrophages. While in control donors these small macrophages accounted for 6.9% of all macrophages, the percentage of these cells in COPD was 45.7%. CD14 and HLA-DR expression was high on these small sputum macrophages while the large sputum macrophages expressed only low levels of these surface molecules, both in control donors and COPD patients. Small sputum macrophages of both control donors and COPD patients showed higher levels of constitutive tumour necrosis factor (TNF) compared to the large macrophages. TNF was inducible by lipopolysaccharide (LPS) preferentially in the small sputum macrophages in the control donors but there was no further induction in COPD patients. These data show that the small sputum macrophages are a major macrophage population in COPD and that these cells exhibit features of highly active inflammatory cells and may therefore be instrumental in airway inflammation in COPD.  相似文献   
75.
The purpose of this study was to assess the time of onset of action of acrivastine in suppressing the wheal response to histamine (10 mg/ml) and allergen (10000 and 100000 BU/ml) in the skin prick test. Ten subjects with a well-documented allergy to pollen received single doses of 8 mg of acrivastine and placebo according to a randomized, double-blind, placebo-controlled, crossover treatment design. Duplicate skin prick tests were performed 0, 15, 20, 25, 30, and 60 min after medication. The results demonstrated a statistically significant suppression of the wheal reactions 15–20 min after medication, depending on the reaction producers used. The sum of all three producers showed a statistically significant effect on the wheal reaction 15 min after medication. The upper 95% confidence limit for time lag from dosing of acrivastine until reduction from placebo level commences was 6.5 min. The study substantiates that orally administered acrivastine has a rapid onset of action in the skin of allergic subjects. The results indicate that allergen SPT is a more sensitive tool for studying antihistaminergic activity than histamine SPT.  相似文献   
76.
The lymphotoxin-beta receptor (LTbetaR) pathway is critical for maintenance of organized lymphoid structures and is involved in the development of colitis. To investigate the mechanisms by which LTbetaR activation contributes to the pathology of chronic inflammation we used a soluble LTbetaR-Ig fusion protein as a competitive inhibitor of LTbetaR activation in the mouse model of chronic colitis induced by oral administration of dextran sulphate sodium. Strong expression of LTbeta which constitutes part of the LTalpha(1)beta(2) ligand complex was detected in colonic tissue of mice with chronic colitis. Treatment with LTbetaR-Ig significantly attenuated the development and histological manifestations of the chronic inflammation and reduced the production of inflammatory cytokines such as TNF, IL-1beta, and IL-6. Moreover, LTbetaR-Ig treatment significantly down-regulated mucosal addressin cell adhesion molecule-1 (MAdCAM-1) expression, leading to reduced leucocyte rolling and sticking in postcapillary and collecting venules and reduced extravasation into the intestinal mucosa as quantified by in vivo fluorescence microscopy. Thus, LTbetaR pathway inhibition ameliorates DSS-induced experimental chronic colitis in mice by MAdCAM-1 down-regulation entailing reduced lymphocyte margination and extravasation into the inflamed mucosa. Therefore, a combined treatment with reagents blocking T cell-mediated perpetuation of chronic inflammation such as LTbetaR-Ig together with direct anti-inflammatory reagents such as TNF inhibitors could constitute a promising treatment strategy for chronic colitis.  相似文献   
77.
BACKGROUND: About 70% of childhood asthmatics become free of asthma-related symptoms during adolescence. Little is known about bronchial hyperresponsiveness (BHR) and airway inflammation in young adults with "outgrown" childhood asthma. METHODS: We studied 61 nonsmoking medical students (18 intermittent mild asthmatics, 23 students with outgrown childhood asthma but free of asthma-related symptoms for 10 years (asymptomatic asthmatics) and 20 healthy students). BHR and lung function were measured, and induced sputum samples analyzed for eosinophil count, eosinophilic cationic protein (ECP), granulocyte-macrophage colony stimulating factor (GM-CSF), and tumor necrosis factor-alpha (TNF-alpha). RESULTS: BHR was still present in most asymptomatic asthmatics, but it was milder compared with healthy students. Only three subjects with previous asthma had no BHR and no signs of airway inflammation. Percentages of eosinophil, and ECP, TNF-alpha and GM-CSF concentrations in induced sputum of mild asthmatics and asymptomatic asthma groups were higher than in the healthy group. In asymptomatic asthmatics group, the duration of asthma, sputum eosinophil percentage, and the level of TNF-alpha in sputum correlated significantly with BHR. CONCLUSIONS: Only a few subjects with longstanding asymptomatic asthma could be considered as cured; most asymptomatic asthmatics continued to exhibit BHR and signs of airway inflammation. The outcome of childhood asthma and BHR was associated with the degree of airway inflammation and the duration of childhood asthma.  相似文献   
78.
红景天苷对新生大鼠海马区神经干细胞分化的研究   总被引:4,自引:0,他引:4  
目的研究红景天苷药物血清诱导新生大鼠海马神经干细胞向神经元方向分化,并促进所分化神经元细胞发育的作用。方法从新生24h内的Wistar大鼠脑中分离扩增获得大量神经干细胞后,加入低、中、高剂量的红景天苷药物血清及对照血清,观察其对神经干细胞分化为神经元的影响,并通过免疫细胞化学染色检测神经干细胞分化为神经元的状况。结果各药物实验组诱导神经干细胞分化为NSE阳性细胞的个数面积与周长明显高于对照组(P<0.05),分化为GFAP阳性细胞的个数明显低于对照组,且呈量效依赖关系。结论红景天苷药物学清在体外可促进神经干细胞向神经元方向分化,在一定范围内存在量效依赖关系,对所分化的神经元细胞有促生长发育作用。  相似文献   
79.
目的 探究miR-30a-3p与NOD1的靶向关系,及其对心肌细胞缺氧复氧损伤的影响和机制。 方法 将细胞分为Ctrl组、H/R组、miR-30a-3p mimic组和miR-30a-3p inhibitor组,经过缺氧复氧处理后,转染相应的miRNA处理细胞,RT-PCR检测miR-30a-3p和NOD1基因表达水平,荧光素酶报告检测miR-30a-3p和NOD1靶向关系,Western blot检测NOD1、p-RPI2、p38 MAPK、NF-κB(p65)、cl-caspase-3蛋白表达水平,CCK8法检测细胞活性,Hoechst检测细胞凋亡,试剂盒检测LDH、CK、MDA、T-SOD水平。 结果 miR-30a-3p表达水平随缺氧复氧处理时间增长而下降,NOD1基因表达水平随缺氧复氧处理时间增长而升高。在荧光素酶报告实验中,NOD1 WT+miR-30a-3p mimic荧光素酶活性显著低于NOD1 WT+NC组。与Ctrl组比较,H/R组miR-30a-3p基因表达水平、细胞活性、T-SOD水平降低,NOD1、p-RPI2、p38 MAPK、NF-κB(p65)、cl-caspase-3蛋白表达水平、LDH、CK、MDA水平、细胞凋亡率升高;与H/R组比较,miR-30a-3p mimic组miR-30a-3p基因表达水平、细胞活性、T-SOD水平升高,NOD1、p-RPI2、p38 MAPK、NF-κB(p65)、cl-caspase-3蛋白表达水平、LDH、CK、MDA水平、细胞凋亡率降低,miR-30a-3p inhibitor组miR-30a-3p基因表达水平、细胞活性、T-SOD水平降低,NOD1、p-RPI2、p38 MAPK、NF-κB(p65)、cl-caspase-3蛋白表达水平、LDH、CK、MDA水平、细胞凋亡率升高。 结论 miR-30a-3p可靶向作用于NOD1,缓解心肌细胞缺氧复氧造成的损伤,其作用机制可能与调控NF-κB信号通路有关。  相似文献   
80.
BACKGROUND: Occupational asthma (OA) can be a debilitating disease even when removal from the workplace is achieved. Today, the "gold standard" in the assessment of OA is the bronchial provocation test (BPT). Induced sputum is a non-invasive method of exploring airway inflammation which can provide additional information about such challenges and thus could be applied in OA diagnosis and monitoring. METHODS: We report the study carried out in a grain worker sensitized to Lepidoglyphus destructor (Ld), who suffered from mild asthma at the workplace. Skin prick test and specific serum IgE were measured. Ld-BPT was performed, and the changes in eosinophil rates, and ECP and tryptase levels in induced sputum were studied 30 min and 18 h after Ld-BPT. We also determined the changes in nonspecific bronchial hyperresponsiveness (NSBH), given as PD20 values. To assess the specificity of the changes, we also carried out sputum induction and methacholine challenge after barley-BPT. RESULTS: An isolated immediate response was obtained with Ld-BPT, while barley-BPT was negative. Induced sputum showed higher tryptase levels 30 min after Ld-BPT, and higher eosinophil and epithelial cell percentages and ECP levels 18 h after Ld-BPT. There was also a decrease in methacholine PD20 values after Ld-BPT. Those changes were not observed after barley-BPT. CONCLUSIONS: The study of eosinophilic and mast-cell markers in induced sputum provides additional knowledge about the inflammatory process occurring in the airways, suggesting that the study of induced sputum should be considered in the assessment of OA.  相似文献   
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