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61.
目的 肝纤维化是一种由于反复肝损伤而导致肝组织细胞外基质过多沉积导致的疾病。缺氧损伤为肝损伤的一部分,缺氧诱导因子-1α(HIF-1α)是响应缺氧应激的关键转录因子,在肝纤维化组织和活化的肝星状细胞(HSC)表达显著增加。目前,通过对大量HIF-1α依赖性基因和信号通路的研究,确认这些基因及其通路的变化参与肝纤维化发展过程,并可能在肝纤维化发生发展过程中起关键作用。本文综述了HIF-1α相关的信号通路参与肝纤维化发展的相关机制,并对上游影响HIF-1α合成和降解的相关信号通路进行了阐述,为其作为新型治疗靶点的可能潜力提供依据。  相似文献   
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目的研究小细胞肺癌(SCLC)患者外周血中辅助性T细胞1(Th1)、Th2、Th17及调节性T淋巴细胞(Treg)的表达情况,探讨其在SCLC进展中的作用。方法选择2016年1月至2018年4月本院收治的44例住院的SCLC患者(SCLC组)及24名健康者(对照组)作为研究对象。采用流式细胞法检测两组研究对象外周血中Th1、Th2、Th17及Treg细胞的表达情况,应用微量样本多指标流式蛋白定量技术(CBA)检测血清中的细胞因子IFN-γ、IL-17及IL-10的表达情况。结果SCLC组患者的外周血中Th1细胞、Th1/Th2、IFN-γ表达水平显著低于对照组,差异具有统计学意义(P<0.01)。SCLC组患者的外周血中Th2、Treg、Th17、Treg/Th17、IL-17、IL-10表达水平显著高于对照组,差异具有统计学意义(P<0.01)。结论SCLC患者外周血中Th1/Th2的降低、Treg/Th17的升高可能与SCLC的致病机理及预后密切相关,该结论将为SCLC的治疗提供新的思路。  相似文献   
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《Clinical neurophysiology》2021,132(2):315-322
ObjectivePrevious studies have demonstrated voluntary movement alterations as well as motor cortex excitability and plasticity changes in patients with mild cognitive impairment (MCI). To investigate the pathophysiology of movement abnormalities in MCI, we tested possible relationships between movement abnormalities and primary motor cortex alterations in patients.MethodsFourteen amnestic MCI (aMCI) patients and 16 healthy controls were studied. Cognitive assessment was performed using clinical scales. Finger tapping was recorded by a motion analysis system. Transcranial magnetic stimulation was used to test the input/output curve of motor evoked potentials, intracortical inhibition, and short-latency afferent inhibition. Primary motor cortex plasticity was probed by theta burst stimulation. We investigated correlations between movement abnormalities, clinical scores, and cortical neurophysiological parameters.ResultsMCI patients showed less rhythmic movement but no other movement abnormalities. Cortical excitability measures were normal in patients, whereas plasticity was reduced. Movement rhythm abnormalities correlated with frontal dysfunction scores.ConclusionOur study in MCI patients demonstrated abnormal voluntary movement and plasticity changes, with no correlation between the two. Altered rhythm correlated with frontal dysfunction.SignificanceOur results contribute to the understanding of pathophysiological mechanisms of motor impairment in MCI.  相似文献   
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PurposeTo investigate the reproducibility of diffusion-weighted (DW) MRI and 18F-Fluorodeoxyglucose (18F-FDG)-Positron emission tomography/CT (PET/CT) in monitoring response to neoadjuvant chemotherapy in epithelial ovarian cancer.Materials and methodsTen women (median age, 67 years; range: 41.8–77.3 years) with stage IIIC-IV epithelial ovarian cancers were included in this prospective trial (NCT02792959) between 2014 and 2016. All underwent initial laparoscopic staging, four cycles of carboplatine-paclitaxel-based chemotherapy and interval debulking surgery. PET/CT and DW-MRI were performed at baseline (C0), after one cycle (C1) and before surgery (C4). Two nuclear physicians and two radiologists assessed five anatomic sites for the presence of ≥ 1 lesion. Target lesions in each site were defined and their apparent diffusion coefficient (ADC), maximal standardized uptake value (SUV-max), SUV-mean, SUL-peak, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were monitored (i.e., 10 patients × 5 sites × 3 time-points). Their relative early and late changes were calculated. Intra/inter-observer reproducibilities of qualitative and quantitative analysis were estimated with Kappa and intra-class correlation coefficients (ICCs).ResultsFor both modalities, inter- and intra-observer agreement percentages were excellent for initial staging but declined later for DW-MRI, leading to lower Kappa values for inter- and intra-observer variability (0.949 and 1 at C0, vs. 0.633 and 0.643 at C4, respectively) while Kappa values remained > 0.8 for PET/CT. Inter- and intra-observer ICCs were > 0.75 for SUV-max, SUL-peak, SUV-mean and their change regardless the time-point. ADC showed lower ICCs (range: 0.013–0.811). ANOVA found significant influences of the evaluation time, the measurement used (ADC, SUV-max, SUV-mean, SUV-max, SUL-peak, MTV or TLG) and their interaction on ICC values (P = 0.0023, P< 0.0001 and P =0.0028, respectively).ConclusionWhile both modalities demonstrated high reproducibility at baseline, only SUV-max, SUL-peak, SUV-mean and their changes maintained high reproducibility during chemotherapy.  相似文献   
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Skin cancer is the deadliest type of malignant disease and causes primary mortality worldwide. Dioscin, which exists in medicinal plants, has potent anticancer effects. However, its effects on skin cancer remain unknown. In the present study, the activity and mechanism of dioscin on the human skin cancer A431 cell line were investigated, MTT, colony formation, Transwell, wound-healing, TUNEL, Comet, immunofluorescence and western blot assays were used to assess the effects of dioscin on A431 cells. The results of MTT, colony formation, Transwell and wound-healing assays revealed that dioscin suppressed proliferation, colony formation and invasion of the cancer cells. TUNEL and comet assays demonstrated that dioscin exhibited significant effects on cell apoptosis and DNA damage. Investigations into the mechanism revealed that the expression levels of phosphorylated Ataxia telangiectasia-mutated (ATM) were considerably activated by dioscin, which significantly upregulated the expression levels of p53 to activate mitochondrial apoptosis signaling. Furthermore, the expression levels of BAX, cleaved caspase-3/9 and cleaved poly (ADP-ribose) polymerase were upregulated, and the expression levels of BCL-2 were downregulated by dioscin. Additionally, dioscin markedly downregulated the expression levels of matrix metalloproteinase 2 (MMP2), MMP9, RHO and cdc42, which are all associated with tumor invasion. In addition, p53-small interfering RNA transfection experiments indicated that dioscin exhibited excellent activity against skin cancer in vitro by decreasing p53 expression. Overall, the present results suggested that dioscin inhibited skin cancer cell proliferation via adjusting ATM/p53-mediated cell apoptosis, migration and DNA damage, which should be considered as a potential option for future treatments of skin cancer.  相似文献   
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目的:探讨血清p53抗体异常高水平对消化道肿瘤的早期诊断的价值。方法:选取2016年3月至2019年3月来我院检查确诊为消化道肿瘤的患者80例为消化道肿瘤组,选取来我院健康体检的67例健康志愿者为健康对照组。通过酶联免疫吸附实验检测血清中人体抑癌基因p53及其抗体水平;通过RT-qPCR检测血清中细胞凋亡相关基因Bcl-2、Bax和Caspase-3蛋白表达量。采用Pearson相关性分析明确消化道肿瘤p53、p53抗体水平和Bcl-2、Bax、Caspase-3蛋白表达水平的关系。结果:消化道肿瘤组p53水平降低,p53抗体水平异常升高(P<0.05)。与健康对照组相比,消化道肿瘤组Bcl-2表达量增加,Bax和Caspase-3蛋白表达量降低(P<0.05)。消化道肿瘤p53水平与Bcl-2蛋白表达水平呈负相关关系,与Bax、Caspase-3蛋白表达水平均呈正相关关系;p53抗体水平和Bcl-2蛋白表达水平呈正相关关系,与Bax、Caspase-3蛋白表达水平均呈负相关关系(P<0.05)。结论:消化道肿瘤患者血清p53抗体异常高水平,可作为临床辅助诊断消化道肿瘤的可靠指标之一。  相似文献   
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We demonstrate the case of a surgery in a patient with irreducible atlantoaxial dislocation (IrAAD) after C2 fracture. The challenges of this case were the flexed head in a forced position, impossibility of neck extension, and revision operation after posterior occipito-cervical fixation. The patient underwent the following surgeries: 1. A ventral release of C1-C2 using transcervical endoscopy; 2. Removal of occipito-cervical system and fibrous block resection in the posterior surfaces of the C1-C2; 3. Reducing of AAD and odontoid screw fixation; 4. Posterior C1-C2-C3 screw fixation. Ankylosing of C1-C2 and C2-C3-C4 fusion was verified by computed tomography scan. There was an improvement in patient status as observed by the increase of the SF-36 scale scores.The use of endoscopic transcervical approach is a good alternative to the transoral approach. Comparative studies of these methods should be performed regarding the choice of an optimal method of decompression in cases of IrAAD.  相似文献   
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