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91.
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Cyclosporine A is one of the most widely used drugs in organ transplant and oncology patients. But its use is accompanied by many toxicities. This study aimed to investigate the possible protective effect of Costus afer (C. afer) leaf extract on cyclosporine A-induced testicular toxicity. This study was carried out on 40 adult male Wistar rats were divided into four groups: control, C. afer, cyclosporine A and cyclosporine A+ C. afer groups. The investigations include genital weight, sperm count and characters, serum luteinising hormone (LH) and testosterone, testicular tissue contents of reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) and lipid peroxidation (MDA). Besides, a histopathological examination of testicular tissue stained with haematoxylin and eosin (H & E) was performed. Cyclosporine A+ C. afer group showed a significant increase in the genital weight, serum testosterone, sperm count, motility and viability. Besides, the extract significantly decreased testicular content of MDA and increased SOD, CAT and GSHPx. C. afer coadministration significantly decreased serum LH and sperm abnormalities and protected against testicular histopathological alterations. The extract showed a protective effect against testicular toxicity associated with cyclosporine A and that was through an antioxidant mechanism.  相似文献   
93.
Nonadherence to hypertensive medications is the most common predisposing factor associated with acute aortic dissections. Acute dissections are more likely to occur in African Americans due to higher rates of uncontrolled hypertension. Through a patient case study, the effects of racial and socioeconomic disparities will be illustrated. Through discussing the case of a 39-year-old African American man who presented with hypertensive crisis and nonadherence to hypertension treatment resulting in the diagnosis of an acute aortic dissection. His case exemplifies the effect of health disparities on postoperative outcomes, morbidity, and mortality in the African American population diagnosed with aortic dissections.  相似文献   
94.
Psoriasis is a multifactorial, recurring, and chronic inflammatory skin disease characterized by hyperproliferation of keratinocytes. Evidence is rapidly accumulating for the role of microRNAs in psoriasis. The object of the study was to explore the functions and precise mechanism of miR-142–3p in human keratinocyte HaCaT cells in the presence of M5. Here, the results showed that miR-142–3p expression was heightened in HaCaT cells induced by M5. In addition, inhibition of miR-142–3p dramatically restricted cell proliferation and enhanced apoptosis in HaCaT cells exposed to M5, as exemplified by a decrease in the antiapoptotic Bcl-2 protein, concomitant with an increase in the proapoptotic proteins Bax. Moreover, depleting miR-142–3p effectively ameliorated M5-induced inflammation response, as reflected by the attenuation of multiple inflammatory factors. Importantly, Sema3A was identified as an authentic target of miR-142–3p, and indeed regulated by miR-142–3p. Mechanistically, silencing of Sema3A effectively abolished the anti-proliferative, apoptosis-promoting, and anti-inflammatory effects of miR-142–3p inhibition in keratinocytes. Taken together, these data elucidated that repression of miR-142–3p protect HaCaT cells against M5-induced hyper-proliferation and inflammatory injury by suppressing its target Sema3A, implying that the miR-142–3p/Sema3A axis may be a new target for preventing keratinocyte injury process. These findings provide a new and better understanding of the mediating role of miR-142–3p in psoriasis.  相似文献   
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目的:研究KIF20A对胶质瘤U87细胞系增殖、侵袭、迁移、凋亡及细胞周期分布的影响。方法:利用 RNA干扰技术下调胶质瘤细胞系 U87中 KIF20A 的表达。RT-qPCR 和 Western blot 分别检测 KIF20A 在mRNA 和蛋白水平上的表达。CCK-8 实验检测 U87细胞增殖能力的变化,Transwell 实验检测U87细胞迁移及侵袭能力的变化,流式细胞术检测 U87细胞凋亡及细胞周期的变化。结果:RT-qPCR和Western blot 结果显示 siRNA-KIF20A显著下调 KIF20A 的表达,CCK-8和Transwell 实验显示下调 KIF20A 的表达显著抑制了U87细胞的增殖、迁移及侵袭能力,流式细胞术结果显示下调 KIF20A 的表达显著促进了U87细胞的凋亡,诱导细胞周期阻滞在G0/G1期。结论:下调KIF20A的表达抑制胶质母细胞瘤细胞的增殖、迁移及侵袭,促进胶质母细胞瘤细胞的凋亡并诱导细胞周期G0/G1期阻滞。  相似文献   
97.
Lung cancer is the leading cause of cancer‐related deaths worldwide. Epidermal growth factor receptor‐tyrosine kinase inhibitors (EGFR‐TKI) often have good clinical activity against non–small cell lung cancer (NSCLC) with activating EGFR mutations. Osimertinib, which is a third‐generation EGFR‐TKI, has a clinical effect even on NSCLC harboring the threonine to methionine change at codon 790 of EGFR (EGFR T790M) mutation that causes TKI resistance. However, most NSCLC patients develop acquired resistance to osimertinib within approximately 1 year, and 40% of these patients have the EGFR T790M and cysteine to serine change at codon 797 (C797S) mutations. Therefore, there is an urgent need for the development of novel treatment strategies for NSCLC patients with the EGFR T790M/C797S mutation. In this study, we identified the EGFR T790M/C797S mutation‐derived peptide (790‐799) (MQLMPFGSLL) that binds the human leukocyte antigen (HLA)‐A*02:01, and successfully established EGFR T790M/C797S‐peptide‐specific CTL clones from human PBMC of HLA‐A2 healthy donors. One established CTL clone demonstrated adequate cytotoxicity against T2 cells pulsed with the EGFR T790M/C797S peptide. This CTL clone also had high reactivity against cancer cells that expressed an endogenous EGFR T790M/C797S peptide using an interferon‐γ (IFN‐γ) enzyme‐linked immunospot (ELISPOT) assay. In addition, we demonstrated using a mouse model that EGFR T790M/C797S peptide‐specific CTL were induced by EGFR T790M/C797S peptide vaccine in vivo. These findings suggest that an immunotherapy targeting a neoantigen derived from EGFR T790M/C797S mutation could be a useful novel therapeutic strategy for NSCLC patients with EGFR‐TKI resistance, especially those resistant to osimertinib.  相似文献   
98.
丝穗金粟兰化学成分研究   总被引:2,自引:2,他引:0  
陈芳有  邹雍  陈杰  黄伟明  卞玉婷  罗永明 《中草药》2020,51(6):1485-1490
目的对丝穗金粟兰Chloranthus fortunei的化学成分进行研究。方法利用多种色谱分离方法和波谱学鉴定方法对丝穗金粟兰中的化学成分进行了分离鉴定,并借助MTT法对其中得到的部分化合物进行了抗肿瘤活性的初步筛选。结果从丝穗金粟兰95%乙醇提取物中分离得到16个化合物,分别鉴定为迷迭香酸(1)、2′-羟基-4,3′,4′,6′-四甲氧基查耳酮(2)、卡瓦胡椒素A(3)、cycloshizukaol A(4)、白术内酯III(5)、4β-hydroxy-8,12-epoxyeudesma-7,11-diene-1,6-dione(6)、(8α)-6,8-dihydroxycadina-7(11),10(15)-dien-12-oic acidγ-lactone(7)、curcolonol(8)、11-hydroxyldrim-8,12-en-14-oic acid(9)、木栓酮(10)、异香草酸(11)、6β-hydroxystigmast-4-en-3-one(12)、3,4-二羟基苯甲酸(13)、莽草酸(14)、东莨菪苷(15)以及N-acetyltyramine 1-O-β-D-glucoside(16)。化合物4和5表现出微弱的细胞毒作用,半数抑制浓度(IC50)值在46~85μmol/L。结论化合物2、10、11、13~15为首次从金粟兰属植物中获得,化合物1~3、6~16为首次从丝穗金粟兰中分离得到。丝穗金粟兰中部分倍半萜显示出弱的抗肿瘤活性。  相似文献   
99.
益智仁化学成分研究   总被引:4,自引:2,他引:2  
目的研究益智Alpinia oxyphylla仁的化学成分。方法采用硅胶、MCI柱色谱、Sephadex LH-20、重结晶、半制备液相进行分离纯化,根据理化性质及波谱数据鉴定所得化合物的结构。结果从益智仁95%乙醇提取物的醋酸乙酯部位分离并鉴定16个化合物,分别鉴定为邻苯二甲酸-双(2′-乙基庚基)酯(1)、(E)-1-(4′-hydroxy-3′-methoxyphenyl)-7-(4″-hydroxyphenyl)-hept-4-en-3-one(2)、5-hydroxy-7-(4″-hydroxy-3″-methoxyphenyl)-1-phenyl-3-heptanone(3)、1β,4β,7β-trihydroxyeudesmane(4)、bullatantriol(5)、1,5-epoxy-3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-7-(4-hydroxy-3-methoxyphenyl) heptanes(6)、1-tetratriacontanol(7)、dihydrogingerenone B(8)、杨芽黄素(9)、白杨素(10)、oxyphyllenone B(11)、(1R,4R,10R)-1β,4α-dihydroxy-11,12,13-trinor-5,6-eudesmen-7-one(12)、胡萝卜苷(13)、1-(4′-羟基苯基)-7-(3″-甲氧基-4″-羟基苯基)-4-烯-3-庚酮(14)、益智酮甲(15)、5-dehydroxy-hexahydro-demethoxycurcumin B(16)。结论其中化合物1、2、4~8为首次从该属植物中分离得到,化合物3为首次从该植物中分离得到。  相似文献   
100.
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