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21.
Non-small cell lung cancer (NSCLC) is the most common type of primary lung cancer and regarded as cancer killer. The aim of this study was to discover the detailed function and molecular mechanism of F-box and leucine rich repeat protein 3 (FBXL3) in NSCLC. In this study, the expression level of FBXL3 in NSCLC tissues and cell lines was firstly examined and identified. Moreover, the relationship between FBXL3 and the overall survival rate of NSCLC patients was analyzed by Kaplan–Meier survival curve. Functionally, MTT, colony formation assay and transwell assays were performed to determine the role of FBXL3 in regulating NSCLC cell proliferation, migration and invasion. The proliferation and migration were suppressed by overexpression of FBXL3, indicating the potential tumor suppressive role of FBXL3 in NSCLC. In addition, the dual-luciferase reporter and RNA pull-down assays revealed that miR-4735-3p was a novel upstream modulator of FBXL3. Further study showed that miR-4735-3p was upregulated in NSCLC tissues and cell lines. Finally, rescue assays and function assays revealed that miR-4735-3p exerted oncogenic function in NSCLC, and this function can be attenuated by FBXL3. Taken together, FBXL3 was regulated by miR-4735-3p and suppressed cell proliferation and invasion in non-small cell lung cancer. 相似文献
22.
目的:检测miR-34c-3p与M2型肿瘤相关巨噬细胞(tumor-associated macrophage,TAM)在三阴性乳腺癌(triple negative breast cancer,TNBC)中的表达,并探讨其在乳腺癌发病中的意义。方法:选择2017年2月至2018年1月于西京医院就诊的68例TNBC患者作为实验组(A组),以同期就诊的70例乳腺纤维腺瘤患者作为对照组(B组)。采用Real-time RT-PCR 检测组织标本中miR-34c-3p的表达;流式细胞检测M2型TAM的表达;ELISA法检测血清中IL-10的表达。并进一步分析miR-34c-3p的表达与乳腺癌M2型TAM及血清IL-10水平的相关性。结果:A、B组miR-34c-3p的相对表达量分别为0.84±0.08、1.29±0.71,A组明显低于B组,差异有统计学意义(P<0.05)。与B组比较,A组M2型TAM(CD68+CD163+)细胞比例显著升高(P<0.05)。A组血清IL-10的表达[(19.69±4.93) pg/ml]较B组[(17.26±3.51) pg/ml]显著升高,差异有统计学意义(P<0.05)。TNBC组织中miR-34c-3p的表达与M2型TAM比例及血清IL-10表达均呈显著负相关(r=-0.508,r=-0.656,P<0.05)。结论:TNBC组织中miR-34c-3p的表达下调,M2型TAM比例及血清IL-10表达均显著升高,促进TNBC进展。 相似文献
23.
目的 明确miR-218在胶质瘤组织中的表达,探讨其对胶质瘤血管生成的作用及机制。方法 采用荧光实时定量PCR法和免疫印迹法检测胶质瘤组织和细胞中miR-218、P70核糖体S6激酶1(p70s6k1)的表达情况,采用基质胶塞实验和小管形成实验分别在体内外检测miR-218对新血管生成的影响。结果 21例胶质瘤组织标本中miR-218表达较7例癌旁组织标本明显下调,且表达量与WHO分级有关。过表达miR-218能显著抑制血管生成。MiR-218直接靶向p70s6k1。过表达p70s6k1能部分逆转miR-218对血管新生的抑制作用。结论 MiR-218能通过靶向p70s6k1的表达调控胶质瘤血管生成,进而影响胶质瘤的进展。 相似文献
24.
目的:研究补骨脂酚对人肝癌细胞凋亡的影响及其作用机制。方法:应用噻唑蓝法(MTT法)和倒置显微镜技术考察补骨脂酚对HepG2细胞生长的影响;采用荧光显微镜观察补骨脂酚处理后细胞凋亡;利用蛋白免疫印迹法检测补骨脂酚对HepG2细胞中凋亡相关蛋白及MAPK家族蛋白表达的影响;引入MAPK家族蛋白抑制剂考察生长抑制率和凋亡相关蛋白表达的变化。结果:补骨脂酚可以剂量依赖性地抑制人肝癌HepG2细胞增殖,其生长抑制作用明显强于临床上常用的抗肿瘤药5-氟尿嘧啶,并且补骨脂酚对人正常肝L02细胞具有较低的毒性。进一步研究发现,补骨脂酚可以诱导HepG2细胞发生凋亡。此外,MAPK家族参与到补骨脂酚诱导的HepG2细胞凋亡过程中,补骨脂酚可以剂量依赖性激活JNK的表达发挥促凋亡的作用,同时抑制了ERK促存活通路,然而对p38无明显影响。结论:本研究首次阐明了补骨脂酚诱导人肝癌HepG2细胞生长抑制作用机制,为进一步的临床应用提供了理论依据。 相似文献
25.
BRCA1-associated protein (BRAP) was first found to bind to the nuclear localization signal motifs of BRCA1. In this study, we investigated the role of BRAP in gastric cancer. The cancer genome atlas(TCGA) data were obtained from UALCAN. We downregulated and upregulated the level of BRAP in gastric cancer cells by transfection with shRNAs and plasmids. Then, we evaluated the expression of BRAP by qRT-PCR and investigated the expression of important proteins by Western blot analysis. We conducted a microarray analysis to identify the function of BRAP in gastric cancer cells. Then, we investigated the effect of BRAP on proliferation and migration by CCK-8 assays, colony formation assays, wound healing assays and an extreme limiting dilution analysis. The analysis of TCGA data showed that BRAP was significantly overexpressed in gastric cancer tissues compared to that in normal gastric mucosal tissues (P < 0.001). A hybridization-based microarray assay was used to analyze MGC-803 cells and BRAP-downregulated MGC-803 cells. We found 22,199 protein-coding RNAs that were differentially expressed. The genes in the two groups were analyzed with the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, and both the focal adhesion and MAPK pathways were significantly enriched. The results of Cell Counting Kit-8(CCK-8) assays, colony formation assays, wound healing assays and the extreme limiting dilution analysis showed that the knockdown of BRAP reduced gastric cancer cell proliferation and migration and inhibited the process of epithelial-mesenehymal transition (EMT). The overexpression of BRAP induced gastric cancer cell proliferation, migration and the process of EMT. To verify the function of the mitogen-activated protein kinase (MAPK) signaling pathway, we performed a Western blot analysis. The results showed that the downregulation of BRAP decreased the levels of p-ERK and p-Raf1, thereby decreasing the activity of the MAPK signaling pathway. The use of Honokiol increased the levels of p-ERK and p-Raf1, rescuing the function of BRAP downregulation in the MAPK pathway. Xenograft tumor transplantation experiments in nude mice further confirmed the role of BRAP in gastric cancer progression and metastasis. 相似文献
26.
背景与目的:Musashi1(Msi1)属于RNA结合蛋白家族中的一员,是RNA转录后表达的关键调控者,其是否参与肿瘤的发生、发展,以及具体分子机制仍不十分清楚。探讨沉默Msi1基因对结肠癌HCT116细胞恶性生物学行为的影响及可能的机制。方法:采用慢病毒载体构建稳定低表达Msi1的细胞株,细胞计数试剂盒(cell counting kit-8,CCK-8)实验检测细胞增殖能力,克隆形成实验检测细胞克隆形成能力,流式细胞术(flow cytometry,FCM)检测细胞周期的变化,裸鼠移植瘤模型观察沉默Msi1对裸鼠成瘤的影响。实时荧光定量聚合酶链反应(real-time fluorescence quantitative polymerase chain reaction,RTFQ-PCR)和蛋白质印记法(Western blot)检测沉默Msi1基因后p27基因的mRNA表达和蛋白水平,双荧光素酶实验验证Msi1基因与目的基因p27 3’-非编码区(3’-untranslated region,3’-UTR)的相互作用。结果:沉默Msi1基因后,HCT116细胞的增殖能力显著下降,克隆集落数明显减少,G 0 /G 1 期细胞增多,S期细胞明显减少,裸鼠移植瘤生长明显受到抑制。沉默Msi1基因后p27 mRNA表达未见明显变化,而p27蛋白水平明显上调,双荧光素酶实验证实Msi1基因能与p27 3’-UTR区域直接结合,抑制其翻译。结论:沉默Msi1基因通过靶向上调p27,导致结肠癌HCT116细胞G 0 /G 1 期阻滞,从而抑制肿瘤细胞体内及体外增殖能力。 相似文献
27.
《European journal of medical genetics》2020,63(6):103919
Neuronal growth regulator 1 (NEGR1), a member of the immunoglobulin superfamily cell adhesion molecule subgroup IgLON, has been involved in neuronal growth and connectivity. Genetic variants, in or near the NEGR1 locus, have been associated with obesity and, more recently, with learning difficulties, intellectual disability, and psychiatric disorders.Here, we described the only second report of NEGR1 gene disruption in 1p31.1 microdeletion in two patients. Patient 1 is a 14-year-old female with neurological and psychiatric features present also in her family. Patient 2 is a 5-month-old infant showing global hypotonia as unique neurological features till now. This patient also carries 7p22.1 duplication, of paternal origin, that could be responsible for some malformations present in the child.We hypothesize a role of NEGR1 in producing the phenotype of our patients and compare them with other cases previously reported in the literature and DECIPHER database to better identify a possible genotype-phenotype correlation. 相似文献
28.
A high salt diet (HSD) is among the most important risk factors for many diseases. One mechanism by which HSD aggravates cerebral ischemic injury is independent of blood pressure changes. The direct role of HSD in inflammation after cerebral ischemia is unclear. In this research, after twenty-one days of being fed a high salt diet, permanent focal ischemia was induced in mice via operation. At 12 h and 1, 3 and 5 days postischemia, the effects of HSD on the lesion volume, microglia polarization, aldose reductase (AR) expression, and inflammatory processes were analyzed. We report that in mice, surplus dietary salt promotes inflammation and increases the activation of classical lipopolysaccharide (LPS)-induced microglia/macrophages (M1). This effect depends on the expression of the AR protein in activated microglia after permanent middle cerebral artery ligation (pMCAL) in HSD mice. The administration of either the AR inhibitor Epalrestat or a p38-neutralizing antibody blocked the polarization of microglia and alleviated stroke injury.In conclusion, HSD promotes polarization in pro-inflammatory M1 microglia by upregulating the expression of the AR protein via p38/MAPK, thereby exacerbating the development of ischemia stroke. 相似文献
29.
Siavash Rahimi Iolia Akaev Peter A. Brennan Azarel Virgo Carla Marani Ricardo S. Gomez Chit Cheng Yeoh 《Journal of oral pathology & medicine》2020,49(2):110-116
The current three-tier grading system (well, moderate and poorly differentiated) used to morphologically classify head and neck squamous cell carcinoma (HNSCC) is inadequate for categorisation of oropharyngeal squamous cell carcinoma (OPSCC) owing to the lack of prognostic value. The aim of this study was to assess the validity of a classification system for OPSCC based on morphology and human papilloma virus (HPV) infection status. Haematoxylin and eosin slides of 121 patients (100 M, 21 F, age range 40-89 years) with OPSCC were reviewed and categorised as histological types I, II and III. The presence of HPV was assessed by immunohistochemistry with p16 and RNAscope In situ hybridization (ISH). The follow-up period was 36 months. Ninety-six patients were p16+ and clinical stage I. Patient survival with types I, II and III was 93%, 50% and 96%, respectively. Twenty-five patients were p16−: 10 clinical stage I and 15 stage III. Amongst this group, no type I morphology was identified. At follow-up, 65% of type II and 75% of type III patients were alive. All p16+ cases were also positive for E6/E7 mRNA high-risk HPV by ISH, while 23 p16− cases were negative and two were positive. Cox regression identified three predictors of mortality: older age (HR = 1.14, 95% CI = 1.06-1.23, P = .001); female gender (HR = 0.22.95% CI 0.05-0.88, P = .033); and type II morphology (HR = 13.1, 95% CI = 1.09-157.0, P = .043). OPSCC morphological classification in three sub-types, along with HPV infection status, seems to reflect the outcome of patients with OPSCC. 相似文献
30.
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