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21.
《Vaccine》2017,35(5):808-813
Infection with the avian leukosis virus subgroup J (ALV-J) can lead to neoplastic disease in chickens, inflicting significant economic losses to the poultry industry. Recent reports have identified inhibitory effects of ALV-J on autophagy, a process involving in innate and adaptive immunity. Inspired by this connection between autophagy and immunity, we developed a novel DNA vaccine against ALV-J which includes co-administration of rapamycin to stimulate autophagy. To measure the efficacy of the developed prototype vaccine, five experimental groups of seven-day-old chickens was immunized three times at three-week intervals respectively with vector, pVAX1-gp85, pVAX1-gp85-LC3, pVAX1-gp85 + rapamycin and pVAX1-gp85-LC3 + rapamycin through electroporation. We then tested their antibody titers, cytokine levels and cellular immune responses. The immunoprotective efficacy of the prototype vaccines against the challenge of the ALV-J GD1109 strain was also examined. The results showed that the combination of pVAX1-gp85-LC3 and rapamycin was able to induce the highest antibody titers, and enhance interleukin(IL)-2, IL-10 and interferon (IFN)-γ expression, and the chickens immunized with the combination of pVAX1-gp85-LC3 and rapamycin showed the highest percentage of CD3+ CD8+ T lymphocytes. Based on our results, we suggest that stimulating autophagy can improve the efficacy of DNA vaccines and that our DNA vaccine shows the potential of being a candidate vaccine against ALV-J. This study provides a novel strategy for developing vaccines against ALV-J.  相似文献   
22.
Osteoarthritis is characterized by continuous degeneration of articular cartilage resulting in disability. The death of chondrocytes and the loss of the extracellular matrix are the central peculiarities in cartilage degeneration during osteoarthritis pathogenesis. Autophagy is an essential cellular homeostasis mechanism whereby cellular organelles and macromolecules are recycled to maintain cellular metabolism. Autophagy is reported to be cytoprotective effects for articular cartilage, and osteoarthritis is associated with decreased autophagy. While autophagy is known to be cytoprotective to chondrocytes, its role may vary with differing stages and models of osteoarthritis. Therefore, more in-depth studies on autophagy are needed to determine its impact on cell survival and death in articular cartilage under various in vitro and in vivo conditions. Application of autophagy on osteoarthritis therapeutics will be possible after a profound understanding is established on the role of autophagy in osteoarthritis pathogenesis.  相似文献   
23.
自噬是机体及细胞必不可少的调节过程,在维持细胞的正常生理状态过程中发挥重要的作用。Beclin1是自噬的核心功能基因之一,其影响自噬体形成,并通过自噬影响肿瘤的发生和发展。研究发现Beclin1在p62蛋白介导的早衰调控中发挥一定作用,电离辐射可引起细胞发生自噬及早衰等细胞反应,导致细胞死亡。研究Beclin1介导的自噬在辐射诱导细胞早衰中的作用对肿瘤的放射治疗有重要意义,可为如何提高肿瘤细胞的放射治疗敏感性这一问题提供参考。综述Beclin1介导的自噬在辐射诱导细胞早衰中作用的相关研究进展,为Beclin1相关的肿瘤放射治疗的理论基础研究提供参考。  相似文献   
24.
目的:探讨雷帕霉素(Rapa)对去甲氧柔红霉素(IDA)诱导急性髓系白血病THP-1细胞凋亡的影响及其分子机制。方法:分别用10、20、40、80 nmol/L Rapa处理THP-1细胞1 h,另设未经Rapa处理的细胞。采用蛋白质印迹法检测THP-1细胞自噬标志物LC3蛋白的转换情况(LC3Ⅱ/LC3Ⅰ),采用流式细胞术检测细胞凋亡,确定Rapa处理浓度。用不同浓度IDA作用THP-1细胞24 h,采用CCK-8法检测IDA对THP-1细胞的增殖抑制率,计算半数抑制浓度( IC50)。以低于 IC50的IDA作用Rapa处理或未处理的THP-1细胞24 h,CCK-8法检测细胞增殖抑制率,流式细胞术检测细胞凋亡情况,实时荧光定量聚合酶链反应检测自噬相关基因Beclin-1、LC3和p62的表达变化,蛋白质印迹法检测自噬标志物LC3蛋白的转换情况。 结果:20 nmol/L Rapa处理的THP-1细胞LC3Ⅱ/LC3Ⅰ高于未处理的细胞( P=0.002 4);80 nmol/L Rapa处理的细胞凋亡率高于未处理的细胞( P=0.007 3)。根据蛋白质印迹法和流式细胞术检测结果,选取20 nmol/L Rapa作为预处理浓度。IDA对THP-1细胞作用24 h的 IC50为59.874 nmol/L。50 nmol/L IDA作用24 h后,Rapa预处理的THP-1细胞增殖抑制率[(69.67±5.03)%比(41.67±3.51)%]和细胞凋亡率[(74.35±4.83)%比(41.25±5.24)%]均高于未预处理的细胞(均 P<0.05);Rapa预处理的THP-1细胞Beclin-1、LC3 mRNA表达水平及LC3Ⅱ/LC3Ⅰ均高于未预处理的细胞,p62 mRNA表达水平低于未预处理的细胞(均 P<0.05)。 结论:Rapa能增强较低剂量IDA诱导的THP-1细胞凋亡,此效应可能是通过其引起THP-1细胞过度自噬实现的。  相似文献   
25.
26.
目的探讨早期宫颈癌组织中自噬相关蛋白-12(ATG-12)与人乳头瘤病毒(HPV)16-E6/E7-DNA病毒载量及预后的关系。方法选取2015年1月至2017年12月期间在安徽皖北煤电集团总医院保存的宫颈活检或手术切除宫颈组织203例,包括30例慢性宫颈炎、18例宫颈上皮内瘤变(CIN)Ⅰ、23例CINⅡ、26例CINⅢ和106例早期(ⅠA2~ⅡB期)宫颈鳞状上皮癌(CSCC)。采用巢式多重聚合酶链式反应(NM-PCR)和免疫组化染色SP法检测组织中HPV 16-E6/E7-DNA病毒载量和ATG-12蛋白表达。分析ATG-12蛋白表达与早期CSCC临床病理特征的关系。随访CSCC患者无瘤生存时间(DFS)。采用Cox风险比例回归模型分析影响CSCC预后的因素。结果CSCC组织ATG-12蛋白阳性表达率为26.42%(28/106),低于慢性宫颈炎和CIN组织(P<0.05)。ATG-12蛋白表达与HPV16-E6/E7-DNA病毒载量呈负相关(r=-0.306,P=0.001;r=-0.436,P=0.001)。ATG-12蛋白表达与FIGO分期、间质浸润、淋巴脉管间隙浸润、淋巴结转移有关(P<0.05)。随访11~64个月,ATG-12蛋白阳性表达患者5年无瘤生存率为78.57%(22/28),ATG-12蛋白表达阴性患者5年无瘤生存率为60.26%(47/78)。多因素Cox风险回归模型结果显示,HPV16-E6/E7-DNA病毒载量和ATG-12蛋白表达是影响患者DFS的独立预后因素(P<0.05)。结论早期宫颈鳞状上皮癌组织中ATG-12阳性表达率低,与HPV16-E6/E7-DNA病毒载量呈负相关,有望成为评估HPV阳性早期宫颈癌患者预后的重要指标。  相似文献   
27.
Objective To observe the formation of autophagosome, the expression and distribution of autophagy-related protein LC3-Ⅰ, LC3-Ⅱ and Beclin-1 in adriamycin nephropathy rats at different pathological periods, to explore the relationship between autophagy and renal tissue injury, the occurrence of proteinuria, the progression of renal disease. Methods Sixty normal male SD rats were randomly divided into control group (n=30) and model group (n=30), the rats in model group were injected with adriamycin(6.5 mg/kg) via tail - vein for one time, while the rats in control group were injected with saline. Urine protein quantitation of 24 hour, the levels of serum albumin and total cholesterol were measured serially at the 2, 4, 6, 8, 10 weeks. The changes of kidney tissue pathology were detected after HE, PAS and Masson staining by light microscope. The formation of autophagy were detected by transmission electron microscopy, the localization and distribution of LC3-Ⅰ, LC3-Ⅱ and Beclin - 1 were detected by indirect immunofluorescence staining in kidney tissue, the autophagy - related proteins LC3-Ⅰ, LC3-Ⅱ and Beclin-1 expression was detected by Western blotting. Results In model group, urinary protein began to increase at the first two weeks, serum albumin decreased at the same time, and total cholesterol increased in the four weeks. There was a statistically significant difference compared with the control group (P<0.01). The Scr and BUN were increased slightly at the four weeks in model group, and showed the deterioration of renal function after the eight weeks. There was a statistically significant difference compared with the control group (P<0.01). Mesangial cell proliferation, mitochondrial swelling and foot process broadening and integration appeared early in the model group, while foot process disappearing and nuclear pyknosis were observed in the late by transmission electron microscope; Renal pathology gradually changed from mesangial proliferation to focal segmental glomerulosclerosis (FSGS) by light microscope. A low expression of autophagy was detected in renal tissue of control group rats by transmission electron microscopy and immunofluorescence microscope; in model group, with the progression of disease, the autophagy was significantly enhanced and maintained at a high level. With the progression of disease, the autophagy- related proteins LC3-Ⅰ, LC3-Ⅱ and Beclin-1 was significantly enhanced in the model group than the control group (P<0.05). Conclusion Autophagy is involved in renal tissue injury and the occurrence of proteinuria, closely related to the progression of renal disease.  相似文献   
28.
目的探讨微RNA-210(miRNA-210)对退行性变髓核细胞自噬的影响及其参与椎间盘退行性变(IDD)进程的可能机制。方法收集24例IDD患者(IDD组)和6例腰椎骨折患者(对照组)椎间盘组织进行分离,培养髓核细胞。通过实时荧光定量聚合酶链反应(FQ-PCR)检测髓核细胞中miRNA-210的表达,通过单丹磺酰尸胺(MDC)染色和蛋白质印迹法检测细胞自噬水平。通过FQ-PCR或蛋白质印迹法检测过表达或抑制miRNA-210对细胞自噬和细胞外基质代谢的影响。通过生物信息学手段寻找miRNA-210与自噬相关的靶基因及miRNA-210的结合位点,并应用双荧光素酶报告实验验证。结果与对照组相比,IDD组髓核细胞中miRNA-210表达量增加,细胞自噬水平降低。过表达miRNA-210会抑制髓核细胞自噬,同时降低Ⅱ型胶原(ColⅡ)及蛋白多糖表达量,升高基质金属蛋白酶-3(MMP-3)和MMP-13表达量。自噬抑制剂3-MA减弱miRNA-210对ColⅡ、蛋白多糖、MMP-3和MMP-13的调节作用。miRNA-210与自噬相关蛋白7(ATG7)存在结合位点,过表达miRNA-210通过沉默ATG7抑制细胞自噬,激活MMP-3和MMP-13,促进细胞外基质(ColⅡ和蛋白多糖)降解。结论在发生退行性变的椎间盘组织中miRNA-210表达量增加。过表达的miRNA-210可能通过直接作用于靶基因ATG7抑制细胞自噬,促进细胞外基质降解,推动IDD进程。  相似文献   
29.
Advanced age is characterized by increased incidence of many chronic, noninfectious diseases that impair the quality of living of the elderly and pose a major burden on the healthcare systems of developed countries. These diseases are characterized by impaired or altered function at the tissue and cellular level, which is a hallmark of the aging process. Age-related impairments are likely due to loss of homeostasis at the cellular level, which leads to the accumulation of dysfunctional organelles and damaged macromolecules, such as proteins, lipids, and nucleic acids. Intriguingly, aging and age-related diseases can be delayed by modulating nutrient signaling pathways converging on the target of rapamycin (TOR) kinase, either by genetic or dietary intervention. TOR signaling influences aging through several potential mechanisms, such as autophagy, a degradation pathway that clears the dysfunctional organelles and damaged macromolecules that accumulate with aging. Autophagy substrates are targeted for degradation by associating with p62/SQSTM1, a multidomain protein that interacts with the autophagy machinery. p62/SQSTM1 is involved in several cellular processes, and its loss has been linked to accelerated aging and to age-related pathologies. In this review, we describe p62/SQSTM1, its role in autophagy and in signaling pathways, and its emerging role in aging and age-associated pathologies. Finally, we propose p62/SQSTM1 as a novel target for aging studies and age-extending interventions.  相似文献   
30.
Colorectal cancer (CRC) is a commonly occurring tumour with poor prognosis. Autophagy-related long non-coding RNAs (lncRNAs) have received much attention as biomarkers for cancer prognosis and diagnosis. However, few studies have focused on their prognostic predictive value specifically in CRC. This research aimed to construct a robust autophagy-related lncRNA prognostic signature for CRC. Autophagy-related lncRNAs from The Cancer Genome Atlas database were screened using univariate Cox, LASSO, and multivariate Cox regression analyses, and the resulting key lncRNAs were used to establish a prognostic risk score model. Furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) analysis was performed to detect the expression of several lncRNAs in cancer tissues from CRC patients and in normal tissues adjacent to the cancer tissues. A prognostic signature comprising lncRNAs AC125603.2, LINC00909, AC016876.1, MIR210HG, AC009237.14, and LINC01063 was identified in patients with CRC. A graphical nomogram based on the autophagy-related lncRNA signature was developed to predict CRC patients'' 1-, 3-, and 5-year survival. Overall survival in patients with low risk scores was significantly better than in those with high risk scores (P < 0.0001); a similar result was obtained in an internal validation sample. The nomogram was shown to be suitable for clinical use and gave correct predictions. The 1- and 3-year values of the area under the receiver operating characteristic curve were 0.797 and 0.771 in the model sample, and 0.656 and 0.642 in the internal validation sample, respectively. The C-index values for the verification samples and training samples were 0.756 (95% CI = 0.668-0.762) and 0.715 (95% CI = 0.683-0.829), respectively. Gene set enrichment analysis showed that the six autophagy-related lncRNAs were greatly enriched in CRC-related signalling pathways, including p53 and VEGF signalling. The qRT-PCR results showed that the expression of lncRNAs in CRC was higher than that in adjacent tissues, consistent with the expression trends of lncRNAs in the CRC data set. In summary, we established a signature of six autophagy-related lncRNAs that could effectively guide clinical prediction of prognosis in patients with CRC. This lncRNA signature has significant clinical implications for improving the prediction of outcomes and, with further prospective validation, could be used to guide tailored therapy for CRC patients.  相似文献   
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