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21.
目的:研究Survivin-shRNA对视网膜母细胞瘤HXO-RB44细胞自噬及凋亡的影响。方法:培养视网膜母细胞瘤HXO-RB44细胞,构建Survivin-shRNA载体。按照处理不同分为Survivin-shRNA组、GFP组和CON组。分别采用流式细胞术检测Survivin-shRNA对HXO-RB44细胞凋亡和细胞周期的影响,应用MTT法检测Survivin-shRNA对HXO-RB44细胞活性的影响,Western blot法检测Survivin-shRNA对HXO-RB44 细胞自噬相关蛋白LC3、p62 与mTOR 表达的影响。结果:流式细胞术结果表明,与Control组和GFP组相比,Survivin-shRNA组细胞凋亡率增加,差异有统计学意义(P<0.05);随着作用时间的延长,S期出现阻滞,48 h阻滞最强,显著高于对照组(P<0.05)。MTT结果发现Survivin-shRNA可抑制HXO-RB44细胞增殖活性,与Control组和GFP组相比,差异有统计学意义(P<0.05);Western blot结果发现,与对照组相比,LC3表达量显著增加(P<0.01);而mTOR表达量降低(P<0.01)。结论:Survivin-shRNA可促进视网膜母细胞瘤HXO-RB44细胞的凋亡和自噬水平,进而特异性杀伤肿瘤细胞。 相似文献
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Tianjiao Lyu Yahui Jiang Nan Jia Xiaoxia Che Qin Li Yinhua Yu Keqin Hua Robert C. Bast Jr Weiwei Feng 《International journal of cancer. Journal international du cancer》2020,146(6):1553-1567
Detachment of cancer cells from the primary tumor and formation of spheroids in ascites is required for implantation metastasis in epithelial ovarian cancer (EOC), but the underlying mechanism of this process has not been thoroughly elucidated. To mimic this process, ovarian cancer cells were grown in 3D and 2D culture. Hey and OVCA433 spheroids exhibited decreased cell proliferation and enhanced adhesion and invasion. SMYD3 expression was elevated in ovarian carcinoma spheroids in association with increased H3K4 methylation. Depletion of SMYD3 by transient siRNA, stable shRNA knockdown and the SMYD3 inhibitor BCI-121 all decreased spheroid invasion and adhesion. Gene expression arrays revealed downregulation of integrin family members. Inhibition assays confirmed that invasion and adhesion of spheroids are mediated by ITGB6 and ITGAM. SMYD3-deficient cells regained the ability to invade and adhere after forced overexpression of SMYD3, ITGB6 and ITGAM. However, this biological ability was not restored by forced overexpression of SMYD3 in ITGB6- and/or ITGAM-deficient cancer cells. SMYD3 and H3K4me3 binding at the ITGB6 and ITGAM promoters was increased in spheroids compared to that in monolayer cells, and the binding was decreased when SMYD3 expression was inhibited, consistent with the expression changes in integrins. SMYD3 expression and integrin-mediated adhesion were also activated in an intraperitoneal xenograft model and in EOC patient spheroids. In vivo, SMYD3 knockdown inhibited tumor metastasis and reduced ascites volume in both the intraperitoneal xenograft model and a PDX model. Overall, our results suggest that the SMYD3-H3K4me3-integrin pathway plays a crucial role in ovarian cancer metastasis to the peritoneal surface. 相似文献
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CD2AP inhibits metastasis in gastric cancer by promoting cellular adhesion and cytoskeleton assembly
Wangkai Xie Chao Chen Zheng Han Jingjing Huang Xin Liu Hongjun Chen Teming Zhang Sian Chen Chenbin Chen Mingdong Lu Xian Shen Xiangyang Xue 《Molecular carcinogenesis》2020,59(4):339-352
Diffuse gastric cancer (DGC) is a lethal malignancy lacking effective systemic therapy. Among the most provocative recent results in DGC has been that the alter of the cellular cytoskeleton and intercellular adhesion. CD2-associated protein (CD2AP) is one of the critical proteins regulating cytoskeleton assembly and intercellular adhesion. However, no study has investigated the expression and biological significance of CD2AP in gastric cancer (GC) to date. Therefore, the aim of our study was to explore if the expression of CD2AP is associated with any clinical features of GC and to elucidate the underlying mechanism. Immunohistochemistry of 620 patient tissue samples indicated that the expression of CD2AP is downregulated in DGC. Moreover, a low CD2AP level was indicative of poor patient prognosis. In vitro, forced expression of CD2AP caused a significant decrease in the migration and invasion of GC cells, whereas depletion of CD2AP had the opposite effect. Immunofluorescence analysis indicated that CD2AP promoted cellular adhesion and influenced cell cytoskeleton assembly via interaction with the F-actin capping protein CAPZA1. Overall, the upregulation of CD2AP could attenuate GC metastasis, suggesting CD2AP as a novel biomarker for the prognosis and treatment of patients with GC. 相似文献
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Shiyu Jiang Yan Qin Hongxin Jiang Biao Liu Jianming Shi Fanlu Meng Peng Liu Jianliang Yang Sheng Yang Xiaohui He Shengyu Zhou Lin Gui Hao Liu Jing Lin Han Han-Zhang Yuankai Shi 《International journal of cancer. Journal international du cancer》2020,147(9):2611-2620
Diffuse large B-cell lymphoma (DLBCL) is a clinically aggressive and heterogenous disease. Although most patients can be cured by immunochemotherapy, 30% to 40% patient will ultimately develop relapsed or refractory disease. Here, we investigated the molecular landscapes of patients with diverse responses to R-CHOP. We performed capture-based targeted sequencing on baseline samples of 105 DLBCL patients using a panel consisting of 112 lymphoma-related genes. Subsequently, 81 treatment-naïve patients with measurable disease and followed for over 1 year were included for survival analysis. Collectively, the most commonly seen mutations included IGH fusion (69%), PIM1(33%), MYD88 (29%), BCL2 (29%), TP53 (29%), CD79B (25%) and KMT2D (24%). Patients with TP53 mutations were more likely to have primary refractory disease (87.0% vs 50.0%, P = .009). For those with TP53 disruptive mutations, 91.7% patients were in the primary refractory group. Interestingly, BCL-2 somatic hypermutation was only seen in patients without primary refractory disease (P = .014). In multivariate analysis, BCL-2 amplification (hazard ratio [HR] = 2.94, P = .022), B2M mutation (HR = 2.99, P = .017) and TP53 mutation (HR = 3.19, P < .001) were independently associated with shorter time to progression (TTP). Furthermore, TP53 mutations was correlated with worse overall survival (P = .049). Next, we investigated mutation landscape in patients with wild-type (WT) TP53 (n = 58) and found that patients harboring MYD88 L265P had significantly inferior TTP than those with WT or non-265P (P = .046). Our study reveals the mutation spectrum of treatment-naive Chinese DLBCL patients. It also confirms the clinical significance of TP53 mutations and indicates the prognostic value of MYD88 L265P in TP53 WT patients. 相似文献
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黄芪始载于《神农本草经》,有补气升阳、益卫固表,利水消肿,托毒生肌之效。被誉为补气健脾之要药,临床上常用于气虚乏力、脾虚泄泻等疾病,已为医者所熟知。近年来,研究学者围绕其补气、健脾、利水功效机制已有较全面的认识。然陶弘景在《本草经集注》首载黄芪"逐五脏间恶血",表明本品兼有活血作用。目前,对于本品活血作用机制阐释,中医常基于"补气活血""气行血行"理论进行论证,但并不等同于本品无活血作用。通过梳理历代本草文献中对黄芪的记载,发现其活血作用应用广泛。综合传统方剂与现代方剂中有关其活血作用的应用,本品在方中行活血通络、活血利水、活血扶正作用,尤能体现其活血作用。且现代药理学研究在有关瘀血病理指标的分子机制中,黄芪有很好的调控作用,表明黄芪有活血作用,但未深入探究,存在研究价值。该文从历代文献对黄芪活血功效的论述、黄芪活血作用的临床应用及现代药理学研究深入探讨其活血作用机制,以期扩展黄芪的临床应用范围,为临床治疗提供理论指导。 相似文献
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目的:观察理冲汤加减联合紫杉醇+卡铂(TC)方案治疗晚期卵巢癌的临床疗效及对患者血液流变学指标、免疫功能及肿瘤标志物水平的影响。方法:选取96例卵巢癌晚期患者,按随机数字表法分为对照组和观察组各48例。对照组给予TC方案治疗,观察组在对照组基础上给予理冲汤加减治疗,21 d为1个疗程,2组均治疗2个疗程。统计2组治疗前后的中医证候积分及治疗期间不良反应发生情况,检测血液流变学指标、T细胞亚群及肿瘤标志物水平,对比2组临床疗效。结果:治疗后,2组少腹包块、腹胀痛、面色无华及形体消瘦积分均较治疗前降低(P0.05),观察组上述4项中医证候积分均低于对照组(P0.05)。观察组疾病控制率77.08%,高于对照组的56.25%(P0.05)。观察组治疗有效率54.17%,对照组治疗有效率41.67%,2组比较,差异无统计学意义(P0.05)。治疗后,2组血液流变学指标(全血黏度高切、全血黏度中切、全血黏度低切、血浆黏度)水平均较治疗前降低(P0.05),观察组上述4项血液流变学指标水平均低于对照组(P0.05)。治疗后,观察组CD3+、CD4+、CD4+/CD8+水平均高于对照组(P0.05),CD8+水平低于对照组(P0.05)。治疗后,2组糖类抗原125 (CA125)、糖类抗原19-9 (CA19-9)、甲胎蛋白(AFP)含量均较治疗前降低(P0.05),观察组CA125、CA19-9、AFP含量均低于对照组(P0.05)。观察组白细胞减少发生率6.25%,低于对照组的27.08%(P0.05)。2组贫血、血小板减少、恶心呕吐、腹泻发生率比较,差异均无统计学意义(P0.05)。结论:理冲汤加减联合TC方案治疗晚期卵巢癌,可以有效改善患者的临床症状、血液流变学指标、免疫功能,降低肿瘤标志物水平,减少化疗产生的不良反应。 相似文献
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