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31.
目的探讨己酮可可碱(pentoxifylline,PTX)对腹腔感染致脓毒症急性肺损伤发挥保护作用的上游信号机制。方法采用盲肠结扎穿孔(cecal ligation and puncture,CLP)致脓毒症模型,将大鼠随机分为假手术组、脓毒症组、脓毒症+西黄著胶组、脓毒症+生理盐水组、脓毒症+SB203580组、脓毒症+PTX组。检测假手术组、脓毒症组各时间点(1,3,6,12,24 h)p38MAPK及IκBα的磷酸化,然后选择1,6,24 h组分别检测应用SB203580或PTX后p38MAPK及IκBα的表达,同时检测血浆TNF-α、IL-6的含量并观察24 h组肺组织病理改变。结果与假手术组比较,脓毒症组在各个时间点p38MAPK及IκBα均有较强的表达,SB203580或PTX预处理后各组的p38MAPK及IκBα的磷酸化明显受到抑制,且与血浆TNF-α、IL-6的含量以及肺的病理切片变化一致。结论 PTX对脓毒症急性肺损伤的保护作用以及抑制促炎因子产生的作用可能是通过抑制p38MAPK的磷酸化从而抑制NF-κB的活化而产生的。  相似文献   
32.
Aim: To investigate the effects of puerarin (Pue), an isoflavone derived from Kudzu roots, on angiotensin II (Ang II)-induced hypertrophy of cardiomyocytes in vivo and in vitro.
Methods: C57BL/6J mice were infused with Ang II and treated with Pue (100 mg·kg-1·d-1, po) for 15 d. After the treatment, systolic blood pressure (SBP) and left ventricular wall thickness were assessed. The ratios of heart weight to body weight (HW/BW) and left ventricular weight to body weight (LVW/BW) were determined, and heart morphometry was assessed. Expression of fetal-type genes (ANP, BNP and β-MHC) in left ventricles was measured using semi-quantitative RT-PCR. Mouse primary cardiomyocytes were treated with Pue (50, 100, 200 μmol/L), then exposed to Ang II (1 μmol/L). ROS level was examined with flow cytometry, the binding activity of NF-κB was determined using EMSA. Western blot was used to measure the levels of ERK1/2, p38 and NF-κB pathway proteins. [3H]leucine incorporation was used to measure the rate of protein synthesis.
Results: Oral administration of Pue significantly suppressed Ang II-induced increases in the myocyte surface area, HW/BW, LVW/BW, SBP and left ventricular wall thickness. Furthermore, Pue significantly suppressed Ang II-induced increases in ANP, BNP and β-MHC expression in the left ventricles in vivo. Treatment of cardiomyocytes with Pue (50–500 μmol/L) did not affect the viability of cardiomyocytes in vitro. Pretreatment of cardiomyocytes with Pue dose-dependently inhibited Ang II-induced increases in ROS production, NF-κB binding activity, protein synthesis and cell breadth. Furthermore, pretreatment with Pue significantly suppressed Ang II-induced activation of ERK1/2, p38 and the NF-κB pathway proteins and the expression of ANP and β-MHC in cardiomyocytes. The positive drug valsartan exerted similar effects on Ang II-induced cardiac hypertrophy in vivo and in vitro.
Conclusion: Pue attenuates Ang II-induced cardiac hypertrophy by inhibiting activation of the redox-sensitive ERK1/2, p38 and the NF-κB pathways.  相似文献   
33.
Non-small-cell lung cancer (NSCLC) is the most common type of lung cancer. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors are commonly used as the first-line treatment for advanced NSCLC; however, the efficacy of drug delivery remains unknown. Hence, we successfully developed erlotinib-conjugated iron oxide nanoparticles (FeDC-E NPs) as theranostic probe that can potentially provide a new avenue for monitoring drug delivering through noninvasive magnetic resonance imaging. MRI ΔR2* relaxivity measurements offer an opportunity to quantitatively evaluate the uptake of FeDC-E NPs at cellular and tumoral levels. Additionally, NF-κB reporter gene system provides NF-κB activation status monitoring to validate the therapeutic efficiency of FeDC-E NPs. FeDC-E NPs not only inhibit the tumor growth and NF-κB-modulated antiapoptotic mechanism but also trigger extrinsic and intrinsic apoptotic pathways. Taken together, dual functional FeDC-E NPs offer diagnostic and therapeutic benefits against lung cancers, indicating that our presented probe could be applied in clinical.  相似文献   
34.
35.
X射线照射对RAW264·7细胞TNF-α和NF-κB表达的影响   总被引:1,自引:0,他引:1  
目的探讨X射线照射诱发小鼠巨噬细胞分泌TNF-α和NF-κB的规律。方法以8Gy X射线单次照射小鼠巨噬细胞系RAW264.7细胞,并于照后不同时间收集细胞培养上清液,采用ELISA法检测RAW264.7细胞TNF-α分泌水平;以8Gy X射线单次照射小鼠巨噬细胞系RAW264.7细胞,并于照后不同时间收集细胞并进行裂解,采用Western blot实验检测NF-кB(p65)的表达。结果 X射线照射能使小鼠巨噬细胞分泌TNF-α增加,在照射后34h达到一次分泌峰值;细胞核中NF-κB(p65)分布增多,并且随着时间的延长其核移位明显增多,照射后4h达到一次最高值。结论 X射线照射能诱发小鼠巨噬细胞TNF-α和NF-κB表达增强。  相似文献   
36.
目的:研究金骨莲胶囊对炎症模型大鼠的抗炎作用及机制.方法:将48只大鼠随机分为空白对照组、模型组、金骨莲胶囊低、中、高剂量组(0.66、1.32、2.64 g/kg)和地塞米松组(阳性对照,0.945 mg/kg),每组8只.空白对照组和模型组大鼠灌胃等体积水,其余各组大鼠灌胃相应药物,每天给药2次,连续3天.末次给药...  相似文献   
37.

Ethnopharmacological relevance

Long-term excess alcohol exposure leads to alcoholic liver disease (ALD)—a global health problem without effective therapeutic approach. ALD is increasingly considered as a complex and multifaceted pathological process, involving oxidative stress, inflammation and excessive fatty acid synthesis. Over the past decade, herbal medicines have attracted much attention as potential therapeutic agents in the prevention and treatment of ALD, due to their multiple targets and less toxic side effects. Several herbs, such as Cnidium monnieri (L.) Cusson (Apiaceae), Curcuma longa L. (Zingiberaceae) and Pueraria lobata (Willd.) Ohwi (Leguminosae), etc., have been shown to be quite effective and are being widely used in China today for the treatment of ALD when used alone or in combination.

Aim of the review

To review current available knowledge on herbal medicines used to prevent or treat ALD and their underlying mechanisms.

Materials and methods

We used the pre-set searching syntax and inclusion criteria to retrieve available published literature from PUBMED and Web of Science databases, all herbal medicines and their active compounds tested on ALD induced by both acute and chronic alcohol ingestion were included.

Results

A total of 40 experimental studies involving 34 herbal medicines and (or) active compounds were retrieved and reviewed. We found that all reported extracts and individual compounds from herbal medicines/natural plants could be beneficial to ALD, which might be attributed to regulate multiple critical targets involved in the pathways of oxidation, inflammation and lipid metabolism.

Conclusions

Screening chemical candidate from herbal medicine might be a promising approach to drug discovery for the prevention or treatment of ALD. However, further studies remain to be done on the systematic assessment of herbal medicines against ALD and the underlying mechanisms, as well as their quality control studies.  相似文献   
38.
39.

Ethnopharmacological relevance

Tripterygium wilfordii Hook f. is one of Traditional Chinese Medicines which is commonly used to treat rheumatoid arthritis (RA). The total alkaloids were the main constituent part of Tripterygium wilfordii Hook f. It has a great significance to study the effects of the total alkaloids of Tripterygium wilfordii Hook f. (ATW) on RA.

Aim of the study

This paper aims at investigating the therapeutic effect of ATW on RA and its possible mechanism, and providing a theoretical and experimental basis for the clinical use of ATW.

Materials and methods

The model of wistar rats of type II collagen-induced arthritis (CIA) was made, and the rats were perfused a stomach with ATW for 4 weeks continuously. Then the levels of interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-<alpha>, in the serum of CIA rats were detected by enzyme linked immunosorbent assay (ELISA), and the joint pathological section of CIA rats was observed by hematoxylin and eosin (HE) staining method and the expression of IL-6, IL-8, nuclear factor kappa B (NF-κB), TNF-α were measure by immunohistochemistry staining method.

Results

Compared with model group, ATW could significantly reduce paw swelling and suppresse articular cartilage degenerated. The results also found that there was significant reduction levels of IL-6, IL-8 and TNF-α in serum of CIA rats treated with ATW and ATW inhibited the expression of IL-6, IL-8, NF-κB, TNF-α in synovial tissue.

Conclusion

ATW not only could inhibit the symptom of CIA rats significantly but also could inhibit the production of IL-6, IL-8, TNF-α in serum and the expression of IL-6, IL-8, NF-κB and TNF-α in synovial tissue targeting the inflammatory. ATW would be a drug as a novel botanical drug for the treatment of RA.  相似文献   
40.
动脉粥样硬化(atherosclerosis, AS)以慢性炎症和增殖过程为特征,而细胞焦亡与AS的发生发展密切相关。核因子κB(nuclear factor kappa-B,NF-κB)的激活可以诱导白介素-1β前体(pro-IL-1β)、白介素-18前体(pro-IL-18)和增加核苷酸结合寡聚化结构域样受体蛋白3(NOD-like receptor protein 3,NLRP3)炎症小体的合成,从而触发半胱氨酸天冬氨酸蛋白酶1前体(pro-Caspase-1)蛋白水解为有活性的半胱氨酸天冬氨酸蛋白酶1(Caspase-1),Caspase-1将细胞因子前体pro-IL-1β和pro-IL-18分别转化为成熟的和具有生物活性的白介素-1β(IL-1β)和白介素-18(IL-18),参与AS形成过程,同时活性Caspase-1可以诱发细胞焦亡,前期研究发现瘀血痹能够减少ApoE-/-小鼠主动脉斑块面积,但机制尚不清楚,同时瘀血痹药物成分可以调节NF-κB、NLRP3、IL-1β等相关因子。因此,拟从NF-κB/NLRP3/IL-1β信号通路介导的细胞焦亡探究瘀血痹抗AS的作用机制,为AS防治提供新的治疗策略。  相似文献   
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