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41.
Fei Pan Hui Mao Ling Deng Guangchao Li Peiliang Geng 《International journal of clinical and experimental pathology》2014,7(9):5622-5633
Recent studies have highlighted the role of microRNA-21 (miR-21) as a prognostic biomarker of breast cancer. However, controversy still remains. The present study aimed to summarize available evidences and obtain a more precise estimation of a prognostic role of miR-21 in breast cancer patients. All eligible studies were searched from PubMed and EMBASE through multiple search strategies. Data were extracted from studies comparing survival in breast cancer patients having higher miR-21 expression with those having lower expression. A meta-analysis was performed to clarify prognostic role of miR-21 in patients with breast cancer. Subgroup analysis was also performed according to patients’ ethnicity. A total of 6 eligible articles comprising 951 cases were selected for this meta-analysis. The combined hazard ratios (HRs) and 95% confidence intervals (95% CIs) for overall survival (OS) were 2.11 (1.09-4.08) and for disease free survival (DFS) was 1.6 (1.30-1.96). Subgroup analysis indicated high miR-21 expression was significantly associated with worse OS in Asian patients (HR = 4.39, 95% CI: 2.47-7.80) but not in non-Asian patients (HR = 1.18, 95% CI: 0.81-1.70). Sensitivity analysis revealed results of this meta-analysis were robust. Odds ratios (ORs) showed that miR-21 expression was closely associated with estrogen receptor (ER), progesterone receptor (PR), lymph node metastasis, histological grade, Her2/neu. The pooled ORs and 95% CIs were 0.53 (0.35-0.80), 0.49 (0.32-0.74), 2.32 (1.54-3.50), 2.44 (1.58-3.75), 4.29 (2.34-7.85), respectively. Our results indicated that elevated miR-21 expression could potentially predict poor survival in patients with breast cancer. 相似文献
42.
目的探讨人结肠癌细胞SW620中细胞周期蛋白1(CCND1)的表达情况及其异常表达对细胞增殖的影响,阐述microRNA-138(miR-138)在SW620增殖中的可能机制。方法采用实时荧光定量聚合酶链式反应(qRT-PCR)以及Western blot确定结肠癌组织和癌旁组织中CCND1的表达情况;随后采用qT-PCR检测结肠癌组织内miR-138的表达,并通过统计学分析miR-138与CCND1表达的相关性,培养SW620细胞并转染miR-138模拟物(mimics)后验证miR-138与CCND1的相关性,在SW620细胞内进一步转染miR-138模拟物后,Transwell和MTT检测不同处理组中细胞增殖和迁移能力的改变情况;继续转染CCND1 siRNA后,探索miR-138影响细胞生物学过程的可能机制。结果结肠癌组织中,与相应癌旁组织相比,CCND1表达显著升高,miR-138表达降低,差异有统计学意义(P<0.05);转染miR-138mimics后,与空白对照组(未转染组)相比,细胞迁徙能力下降,同时增殖降低,差异有统计学意义(P<0.05);转染CCND1 siRNA后,与未转染组相比,miR-138表达变化无显著差异(P>0.05),而细胞侵袭能力和增殖能力较未转染组相比显著改变,差异有统计学意义(P<0.05)。结论结肠癌组织中CCND1异常升高可能与miR-138的表达降低有关,且miR-138影响SW620细胞的迁移和增殖能力可能是通过影响CCND1的表达实现的。 相似文献
43.
Steiner D Avidor-Reiss T Schallmach E Saya D Vogel Z 《Journal of molecular neuroscience : MN》2005,27(2):195-203
It was shown previously that chronic exposure to opiate agonists increases adenylyl cyclase (AC) activity, a phenomenon termed AC superactivation (or supersensitization). More recently, we showed that acute Gi/o- coupled receptor activation inhibits the activity of several AC isozymes, including Ca2+/calmodulin-stimulated AC-I and -VIII, whereas chronic receptor activation induces their superactivation. Here, we report that both acute Mu-opioid receptor-induced inhibition and chronic induced superactivation of AC-I and -VIII are pertussis toxin sensitive. In addition, we show that proteins that interfere with the activity of Gbetagamma subunits (Gbetagamma scavengers) strongly attenuate the acute inhibition of AC-I and -VIII and the superactivation of AC-I, and abolish the superactivation of AC-VIII. Based on these results, we suggest that Gbetagamma is involved in the acute inhibition and chronic agonist-induced superactivation of AC types I and VIII. 相似文献
44.
MicroRNAs (miRNAs)是长度约22个核苷酸左右的内源性、非编码RNA.在心血管疾病状态下,如增殖性血管疾病,心脏肥大,心功不全和缺血性心脏病的心血管组织中,miRNA-21表达下调.miRNA-21在血管平滑肌细胞的增殖、凋亡,心肌细胞生长、死亡及心肌细胞纤维化方面起着重要作用,已被证实参与上述疾病发病过... 相似文献
45.
MicroRNA-224在肝癌HepG2细胞中的表达及其靶基因的预测分析 总被引:1,自引:1,他引:0
目的 应用基因芯片技术研究microRNA-224在肝癌HepG2细胞中的表达,通过生物信息学预测其下游靶基因,并初步揭示其在肝癌发生过程中的作用.方法 利用基因芯片技术筛选得到和正常肝上皮LO2细胞比较差异表达的基因,通过生物信息学预测表达上调的microRNA-224的靶基凶,并对其靶基因进行功能注释.结果 与LO2细胞比较,microRNA-224在肝癌HepG2细胞中旱高表达.MicroRNA-224预测靶基因有264个,其多个基因涉及细胞周期、信号转导、细胞增殖、细胞分化和细胞凋亡等众多生物学过程.结论 MicroRNA-224在肝癌HepG2细胞中呈现高表达,可能间接或直接地调控其下游靶基因表达,在肝癌发生过程中起着重要的作用. 相似文献
46.
Zhenwei Lei Xin Ma Hongzhao Li Yu Zhang Yu Gao Yang Fan Xintao Li Luyao Chen Yongpeng Xie Jianwen Chen Shengpan Wu Lu Tang Xu Zhang 《Urologic oncology》2018,36(3):93.e23-93.e37
Objectives
Dysregulated expression of miR-181a accompanies tumorigenesis in many human cancers. However, in clear cell renal cell carcinoma (ccRCC), the role of miR-181a remains unclear. The aim of this study was to investigate biological functions of miR-181a and its expression levels in ccRCC tissues and cancer cell lines.Material and methods
Expression levels of miR-181a in samples of ccRCC tumors and adjacent nontumor tissues from 42 patients as well as in 786-O, 769-P, A498, and CAKI-1 ccRCC cell lines were determined by quantitative real-time polymerase chain reaction. Potential targets of miR-181a were predicted using bioinformatic approaches and then verified by using the luciferase reporter assay. The effects of miR-181a on cell proliferation, colony formation, cell cycle progression, and apoptosis were investigated in ccRCC cell lines transfected with specific miR-181a mimic and inhibitor.Results
We found that miR-181a expression was up-regulated in ccRCC tissues and cell lines. The expression level of miR-181a significantly correlated with the tumor size, tumor/node/metastasis staging, and Fuhrman grade. Luciferase assays showed that KLF6 was a target of miR-181a. KLF6 expression was inversely correlated with the level of miR-181a. Overexpression of miR-181a led to reduced KLF6 mRNA and protein levels, whereas mutations of the potential miR-181a binding sites in the KLF6 gene abrogated this inhibitory effect. Furthermore, overexpression of miR-181a promoted proliferation and G1/S cell cycle transition, as well as inhibited apoptosis by down-regulating KLF6 in ccRCC cells.Conclusions
miR-181a is up-regulated in ccRCC and may act as a tumor promoting factor by targeting KLF6 expression. Manipulating miR-181a may provide a beneficial effect in the treatment of ccRCC. 相似文献47.
《Immunobiology》2022,227(6):152295
ObjectivePrevious works have outlined the pivotal involvement of long intergenic non-coding RNA (lincRNA) in cancer progression, while the efficiency of LINC01234 in pancreatic cancer remained obscure. The purpose of this research is to unravel the regulatory mechanism of LINC01234 in pancreatic cancer via modulating microRNA (miR)-513a-3p and hexose 6-phosphate dehydrogenase (H6PD).MethodsPancreatic cancer cells were cultured and clinical tissue specimens were collected. LINC01234, miR-513a-3p and H6PD levels in pancreatic cancer cells and tissues were examined. Plasmids altering LINC01234, miR-513a-3p and H6PD expression were transfected into pancreatic cancer cells to assess the change in biological behaviors of pancreatic cancer cells. The targeting relations among LINC01234, miR-513a-3p and H6PD were validated.ResultsLINC01234 and H6PD levels were elevated while miR-513a-3p level was reduced in pancreatic cancer cells and tissues. LINC01234 deficiency hindered the malignant biological activities of pancreatic cancer cells. MiR-513a-3p depletion or H6PD elevation could abrogate the inhibitory effects of LINC01234 silencing on pancreatic cancer cells. LINC01234 sponged miR-513a-3p that targeted H6PD.ConclusionThe reduced LINC01234 exerts inhibitory impacts on pancreatic cancer cells via targeting miR-513a-3p to restrain H6PD level. The current study broadens the understanding of LINC01234 function and affords novel therapeutic targets for pancreatic cancer treatment. 相似文献
48.
目的探讨miR-195对脂多糖(LPS)诱导的H9C2心肌细胞凋亡、氧化应激、炎症反应的影响。方法将H9C2心肌细胞随机分成空白对照组、脂多糖组(LPS)、LPS+miR-NC组、LPS+miR-195组;RT-PCR检测转染后miR-195表达量;ELISA检测心肌损伤标记物水平(CK-MB、Mb、cTnI);流式细胞术检测细胞凋亡率;Hoechst染色观察细胞核形的变化;Western blot检测氧化应激相关蛋白表达(p-Nrf2/Nrf2、PGC-1α);试剂盒检测氧化应激标记物SOD活性;ELISA检测炎症因子水平(IL-6、IL-1β、iNOS)。结果与LPS+miR-NC组相比,LPS+miR-195组miR-195表达量、氧化应激标记物水平(p-Nrf2/Nrf2、PGC-1α)、抗氧化酶SOD活性均显著升高(P<0.05);与LPS+miR-NC组相比,LPS+miR-195组心肌损伤标记物水平(CK-MB、Mb、cTnI)、细胞凋亡率、炎症因子水平(IL-6、IL-1β、iNOS)均显著降低(P<0.05);与LPS+miR-NC组相比,LPS+miR-... 相似文献
49.
miR-451对胶质瘤细胞株A172生物学特征的影响 总被引:1,自引:1,他引:0
目的 研究miR-451对胶质瘤细胞株A172生物学特征的影响.方法 合成寡核苷酸miR-451拟似物(miR-451 mimics)转染胶质瘤细胞以上调miR-451的表达,real-time PCR检测转染后miR-451的表达,Western印迹法检测目标蛋白表达,应用流式细胞术、MTT法评价细胞生长和增殖的生物学特征变化.结果 转染miR-451 mimics后,real-time PCR检测提示miR-451表达升高,Western blot结果显示癌基因C-myc表达下降>63.6%,细胞周期正向调节因子CDK2、CDK4、Cyclin D1和Cyclin E表达下降;细胞周期分析表明miR-451 mimics组进入G0/G1期的细胞数较对照组增多达17.4%,出现G0/G1期阻滞;MTT法分析显示miR-451 mimics组细胞生长受抑.结论 miR-451可以抑制人脑胶质瘤细胞生长和增殖能力,具有抑瘤作用. 相似文献
50.