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991.
992.
Sevoflurane is one of the most commonly used volatile anesthetics. Recent studies have shown that sevoflurane plays an important role in modulation of inflammation and immunity. However, little is known about the related molecular mechanisms. This study was designed to investigate the effects and mechanisms of sevoflurane on inflammatory cell death pyroptosis in the murine macrophage cell line J774 cells. Sevoflurane combined with ATP could increase the level of activated caspase-1, pyroptosis, and reactive oxygen species (ROS). Furthermore, treatment of cells with the caspase-1 inhibitor Ac-YVAD-CMK dramatically decreased the percentage of pyroptosis. In addition, inhibition of ROS with N-acetyl-l-cysteine or diphenyleneiodonium significantly reduced the activated levels of caspase-1. These results demonstrated that sevoflurane combined with ATP could activate caspase-1 and trigger caspase-1-dependent pyroptosis through the modulation of ROS production.  相似文献   
993.
This study aimed to investigate the effects of paeoniflorin, the main active ingredient of the medicinal plant Paeonia lactiflora Pall., on the permeability of endothelial cells induced by lipopolysaccharide (LPS) and the underlying mechanisms. Human umbilical vein endothelial cells (HUVECs) were stimulated by LPS. Extravasated FITC-dextran reflecting permeability was assessed by multimode microplate reader, and the migration of bis-carboxyethyl-carboxyfluorescein acetoxy-methyl-labeled human acute monocytic leukemia cell line and leukemia cell line cells through HUVECs were analyzed by fluorescence microscopy. The phosphorylations of phosphatidylinositol 3-kinase (PI3K)/Akt, protein kinase C (PKC), and cofilin in HUVECs were assessed by western blotting, and the F-actin level was detected by laser scanning confocal microscopy. After LPS stimulation, inflammatory endothelial cells exhibited significantly increased permeability. Paeoniflorin (10, 30, and 100 μM) inhibited dextran extravasation and leukocyte migration through HUVECs induced by LPS in a concentration-dependent manner. Moreover, paeoniflorin was able to suppress the phosphorylations of PI3K/Akt, PKC, and cofilin, as well as F-actin reorganization in HUVECs induced by LPS. These findings revealed that paeoniflorin partly blocked LPS-induced endothelium permeability, supporting a new explanation for its anti-inflammatory effects.  相似文献   
994.
目的 观察大鼠脊髓损伤(SCI)后神经元细胞凋亡和相关调控蛋白Caspase-3表达的时间、空间分布规律。方法 SD大鼠50只,分为假手术组和SCI组,钳夹法建立SCI模型,用结晶紫(CV)染色法、TUNEL法和免疫组织化学方法观察SCI后6h、12h、24h、3d和7d损伤中心到头端0~5.00mm空间范围内脊髓神经细胞存活、凋亡以及相关调控蛋白Caspase-3的表达状况。 结果 CV染色发现,SCI后6h~7d在0~0.50mm空间范围内均未发现存活的神经细胞,在1.00~3.50mm距离内,存活的神经细胞数逐渐增加,4.00mm处达峰值;TUNEL结果发现,SCI后6h~7d在1.05~4.55mm范围内,神经细胞出现凋亡,3d时在2.55mm处,细胞凋亡达高峰,7d时显著减少;免疫组织化学结果发现,SCI后6h~7d在1.10~4.60mm范围内,神经元细胞出现Caspase-3阳性表达,3d在3.10mm处Caspase-3表达达到高峰,7d显著减少。 结论 SCI后,凋亡的神经细胞及其相关调控蛋白Caspase-3的表达有一定的时空分布规律。  相似文献   
995.
Dai  Yanyuan  Shao  Jie  Lang  Yue  Lv  Yudan  Cui  Li 《Neurological sciences》2021,42(10):4209-4219
Neurological Sciences - To summarize the clinical characteristics of patients with sporadic Creutzfeldt-Jakob disease (sCJD), analyze its sleep disorder characteristics using polysomnography (PSG),...  相似文献   
996.
Lysophospholipase, belonging to the complex family of phospholipases, is supposed to play a vital role in virulence and pathogenesis of parasites and fungi. In the current study, the potential role of Clonorchis sinensis lysophospholipase (CslysoPLA) in hepatic fibrosis induced by C. sinensis was explored for the first time. In the liver of the cat infected with C. sinensis, CslysoPLA was recognized in the lumen between adult worms and surrounding bile duct epithelia together with some inside the cells by means of immunolocalization. Both Cell Counting Kit-8 (CCK-8 assay) and cell cycle analysis of human hepatic stellate cell line LX-2 showed that a higher percentage of cells were at proliferation phase after incubation with lower concentrations of recombinant CslysoPLA (rCslysoPLA). Quantitative real-time polymerase chain reaction (RT-PCR) demonstrated an upregulation in fibrogenic genes of smooth muscle α-actin, collagen III, matrix metalloproteinase 2 and tissue inhibitors of metalloproteinase II in LX-2 treated with rCslysoPLA. Moreover, human biliary epithelial cell line 5100 proliferated significantly in response to rCslysoPLA. Notably, CslysoPLA was localized in the adenomatoid hyperplastic tissue within the intrahepatic bile duct of experimentally infected rats by immunolocalization analysis. In addition, quantitative RT-PCR implied that CslysoPLA was differentially expressed at the developmental stages of C. sinensis (metacercariae, adult worms and eggs), with the highest level at metacercariae stage. Immunolocalization analysis showed that CslysoPLA was distributed in the intestine, vitelline gland, tegument and eggs in the adult worms and in the tegument and vitelline gland in the metacercariae, respectively. Collectively, it suggests that CslysoPLA might be involved in the initiation and promotion of C. sinensis-related human hepatic fibrosis and advance future studies on its promotion to C. sinensis-induced cholangiocarcinogenesis.  相似文献   
997.
目的:观察巢蛋白在成年大鼠室周器官细胞的表达,并根据巢蛋白阳性表达细胞的位置、大小及形态特点进行分类.方法:成年SD雄性大鼠,经心灌注后,用免疫组织化学检测巢蛋白在室周器官细胞的表达.结果:在正中隆起(64.32%±8.55%)、穹隆下器(15.76%±2.16%)、连合下器(40.15%±6.16%)和最后区(28.85%±4.53%)都可见大量的巢蛋白阳性表达细胞.根据细胞所在位置、大小和形态将其分为5类.Ⅰ类是室管膜细胞,部分室管膜细胞有长10~180 μm的胞突;Ⅱ类细胞较小,细胞及细胞核呈圆形或卵圆形,有1~2个纤细长达20~30 μm的胞突;Ⅲ类细胞胞体较Ⅱ类大,细胞及细胞核不规则,胞质浅染,无胞突;Ⅳ类细胞及细胞核呈圆形或卵圆形,大部分细胞无胞突,部分细胞有长4~15 μm的胞突;Ⅴ类细胞胞体较大,细胞及细胞核呈圆形或卵圆形,有1~3个粗长的突起,并可见2~3级分支,胞突长50~100μm.结论:成年大鼠室周器官有大量巢蛋白阳性表达细胞,有的是具有增殖和分化潜能的神经干细胞/祖细胞,有的是巢蛋白阳性表达的神经元.  相似文献   
998.
目的 观察横突、肋横突外侧韧带与脊神经之间的毗邻关系,为提高超声引导下胸椎旁神经阻滞术的安全性及阻滞效能提供解剖学依据。 方法 选用18具标本胸椎节段,取椎板外侧缘和同名脊神经根的十字交点作为测量的起点,分别测量T1~12共12个节段脊神经与横突下后缘中点、肋横突外侧韧带下缘中点之间的距离。根据“3个一组”原则,12个节段共分为4组,记为T1~3组、T4~6组、T7~9组及T10~12组,对不同组别的脊神经-横突间距、脊神经-肋横突外侧韧带间距分别进行单因素方差分析。 结果 (1)脊神经-横突间距:平均为(16.13±5.59)mm,T1~12总体呈先递增后递减的趋势,T5节段最大,为(18.88±5.78)mm,T5向上或向下节段逐渐减小,T1节段为(16.62±3.67)mm,T12节段为(9.76±3.75)mm。自上而下4组的脊神经-横突间距分别为(17.50±4.67)、(18.19±5.62)、(16.92±5.28)及(12.00±4.42)mm,T10~12组相比T1~3组(P<0.01)、T4~6组(P<0.01)、T7~9组(P<0.01)有统计学差异。(2)脊神经-肋横突外侧韧带间距:平均为(17.67±3.76)mm,自上而下4组的间距分别为(16.95±3.82)、(17.55±3.89)、(17.81±3.83)及(18.30±3.43)mm,两两比较均无统计学差异(P>0.05)。 结论 了解脊神经-横突间距、脊神经-肋横突外侧韧带间距利于估算椎旁神经阻滞的安全穿刺深度,以提高阻滞效能,避免脊神经损伤及全脊髓麻醉的风险。  相似文献   
999.
Marfan syndrome (MFS) is a complex connective tissue disease that is primarily characterized by cardiovascular, ocular and skeletal systems disorders. Despite its rarity, MFS severely impacts the quality of life of the patients. It has been shown that molecular genetic factors serve critical roles in the pathogenesis of MFS. FBN1 is associated with MFS and the other genes such as FBN2, transforming growth factor beta (TGF-β) receptors (TGFBR1 and TGFBR2), latent TGF-β-binding protein 2 (LTBP2) and SKI, amongst others also have their associated syndromes, however high overlap may exist between these syndromes and MFS. Abnormalities in the TGF-β signaling pathway also contribute to the development of aneurysms in patients with MFS, although the detailed molecular mechanism remains unclear. Mutant FBN1 protein may cause unstableness in elastic structures, thereby perturbing the TGF-β signaling pathway, which regulates several processes in cells. Additionally, DNA methylation of FBN1 and histone acetylation in an MFS mouse model demonstrated that epigenetic factors play a regulatory role in MFS. The purpose of the present review is to provide an up-to-date understanding of MFS-related genes and relevant assessment technologies, with the aim of laying a foundation for the early diagnosis, consultation and treatment of MFS.  相似文献   
1000.
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