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In patients with triple-negative breast cancer (TNBC), high tumour mutation burden and aberrant oncogene expression profiles are some of the causes of poor prognosis. Therefore, it is necessary to identify aberrantly expressed oncogenes, since they have the potential to serve as therapeutic targets. Transient receptor potential channel 5 opposite strand (TRPC5OS) has been previously shown to function as a novel tumour inducer. However, the underlying mechanism of TRPC5OS function in TNBC remain to be elucidated. Therefore, in the present study TRPC5OS expression was first measured in tissue samples of patients with TNBC and a panel of breast cancer cell lines (ZR-75-1, MDA-MB-453, SK-BR-3, JIMT-1, BT474 and HCC1937) by using qRT-PCR and Western blotting. Subsequently, the possible effects of TRPC5OS on MDA-MB-231 cells proliferation were determined using Cell Counting Kit-8 and 5-Ethynyl-2′-deoxyuridine assays after Lentiviral transfection of MDA-MB-231. In addition, potential interaction partners of TRPC5OS were explored using liquid chromatography-mass spectrometry (LC-MS)/MS. Gene expression patterns following TRPC5OS overexpression were also detected in MDA-MB-231 cells by using High-throughput sequencing. Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) analysis were then used to systematically verify the potential interactions among the TRPC5OS-regulated genes. The potential relationship between TRPC5OS-interacting proteins and gene expression patterns were studied using Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) analysis. TRPC5OS expression was found to be significantly higher in TNBC tumour tissues and breast cancer cell lines compared with luminal tumour tissues and ZR-75-1. In addition, the overexpression of TRPC5OS significantly increased cell proliferation. High-throughput sequencing results revealed that 5,256 genes exhibited differential expression following TRPC5OS overexpression, including 3,269 upregulated genes and 1,987 downregulated genes. GO analysis results indicated that the functions of these differentially expressed genes were enriched in the categories of ‘cell division’ and ‘cell proliferation’ regulation. KEGG analysis showed that the TRPC5OS-regulated genes were associated with processes of ‘homologous recombination’ and ‘TNF signalling pathways’. Subsequently, 17 TRPC5OS-interacting proteins were found using LC-MS/MS and STRING analysis. The most important protein among interacting proteins was ENO1 which was associated with glycolysis and regulated proliferation of cancer. In summary, data from the present study suggest that TRPC5OS overexpression can increase TNBC cell proliferation and ENO1 may be a potential target protein mediated by TRPC5OS. Therefore, TRPC5OS may serve as a novel therapeutic target for TNBC.  相似文献   
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The pandemic of coronavirus disease 2019 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to major public health challenges globally. The increasing viral lineages identified indicate that the SARS-CoV-2 genome is evolving at a rapid rate. Viral genomic mutations may cause antigenic drift or shift, which are important ways by which SARS-CoV-2 escapes the human immune system and changes its transmissibility and virulence. Herein, we summarize the functional mutations in SARS-CoV-2 genomes to characterize its adaptive evolution to inform the development of vaccination, treatment as well as control and intervention measures.  相似文献   
35.
叙事医学是人文医学发展到一定程度的结果,体现了叙事思想在医学实践中的应用。目前国内外研究已经证实,叙事医学不仅在提高医务人员共情能力、自我反思引发、职业认同感增强等方面有良好的治疗效果,对间接改善患者生理、心理等也有很多益处。新生儿医学在我国起步较晚,目前我国的新生儿重症监护室(NICU)需要隔离监护,几乎不能做到母婴同室,甚至无法探视。新生儿科工作压力大,知识更新快,医学生需要在尽快掌握临床技术的前提下加强人文素养。扎实的临床基础是每一个新生儿科医生必备的,医学的发展也要求新生儿科医生在临床工作中的每个环节融入人文关怀精神。通过叙事医学教育,使新生儿科医生主动养成善于倾听患儿以及其背后家庭的故事,理解和同情患儿及其家属的心情及抉择,形成对患儿的共情能力以及专业的职业精神,促成以患儿为中心的临床思维。叙事医学在新生儿医学人文教育方面的研究还需在今后的临床实践中继续推进、不断应用和总结。  相似文献   
36.
目的]探究脑小血管病(CSVD)患者血清8-羟基脱氧鸟苷酸(8-OHdG)、趋化因子C-X3-C配体1(CX3CL1)水平与认知功能障碍的关系。 [方法]选取2021年5月—2022年5月本院收治的CSVD患者128例,依据蒙特利尔认知评估量表(MoCA)评分分为认知障碍组与无认知障碍组两组,测定两组血清8-OHdG、CX3CL1水平,应用Pearson相关性分析血清8-OHdG、CX3CL1水平与CSVD患者MoCA评分的关系,Logistic回归分析影响CSVD患者认知功能障碍的因素,并绘制ROC曲线研究血清8-OHdG、CX3CL1水平对CSVD患者认知功能障碍的预测效能。 [结果]认知功障碍组患者血清8-OHdG和CX3CL1水平分别高于无认知障碍组,但其MoCA评分低于无认知障碍组(均P<0.05)。血清8-OHdG、CX3CL1水平均与MoCA评分呈负相关(r=-0.715、-0.413,P<0.05)。血清8-OHdG水平,重度认知障碍组分别高于中度和轻度认知障碍组(均P<0.05),中度认知障碍组高于轻度认知障碍组(P<0.05)。CX3CL1水平,重度认知障碍组分别高于中度和轻度认知障碍组(均P<0.05),中度认知障碍组高于轻度认知障碍组(P<0.05)。8-OHdG诊断CSVD患者认知功能障碍的ROC曲线下面积(AUC)为0.866,灵敏度、特异度分别为76.53%和80.00%(均P<0.05);CX3CL1诊断CSVD患者认知功能障碍的AUC为0.868,灵敏度、特异度分别为86.73%和80.00%(均P<0.05);8-OHdG、CX3CL1二者联合诊断CSVD患者认知功能障碍的AUC为0.922,灵敏度、特异度分别为88.78%和86.67%(均P<0.05)。血清8-OHdG>2.69 μg/L、CX3CL1>179.18 pg/L均为CSVD患者认知功能障碍的影响因素(P<0.05)。 [结论]血清8-OHdG、CX3CL1水平与CSVD患者认知功能障碍呈正相关,两者可作为预测CSVD患者出现认知功能障碍的辅助指标。  相似文献   
37.
Diseases caused by flaviviruses such as dengue virus (DENV) and West Nile Virus (WNV), are a serious threat to public health. The flavivirus single-stranded RNA genome is translated into a polyprotein which is cleaved into three structural proteins and seven non-structural proteins by the viral and cellular proteases. Non-structural (NS) protein 3 is a multifunctional protein that has N-terminal protease and C-terminal helicase domains. The NS3 protease requires co-factor NS2B for enzymatic activity and folding. Due to its essential role in viral replication, NS2B-NS3 protease is an attractive target for antiviral drugs. Despite the availability of crystal structures, dynamic interactions of the N- and C-termini of NS2B co-factor have been elusive due to their flexible fold. In this study, we employ integrative structural approaches combined with biochemical assays to elucidate the dynamic interactions of the flexible DENV4 NS2B and NS3 N- and C-termini. We captured the crystal structure of self-cleaved DENV4 NS2B47NS3 protease in post cleavage state. The intermediate conformation adopted in the reported structure can be targeted by allosteric inhibitors. Comparison of our new findings from DENV4 against previously studied ZIKV NS2B-NS3 proteins reveals differences in NS2B-NS3 function between the two viruses. No inhibition of protease activity was observed for unlinked DENV NS2B-NS3 in presence of the cleavage site while ZIKV NS2B-NS3 cleavage inhibits protease activity. Another difference is that binding of the NS2B C-terminus to DENV4 eNS2B47NS3Pro active site is mediated via interactions with P4-P6 residues while for ZIKV, the binding of NS2B C-terminus to active site is mediated by P1-P3 residues. The mapping of NS2B N- and C-termini with NS3 indicates that these intermolecular interactions occur mainly on the beta-barrel 2 of the NS3 protease domain. Our integrative approach enables a comprehensive understanding of the folding and dynamic interactions of DENV NS3 protease and its cofactor NS2B.  相似文献   
38.
We assessed associations between polysomnographically determined sleep, especially the amount of slow-wave sleep (SWS), and body mass index (BMI) in patients with insomnia. One hundred and forty-one insomniacs and 55 healthy volunteers completed overnight polysomnographic recordings, and we measured height and body weight. No significant correlations were obtained between total sleep time and BMI among insomniacs. Compared with normal volunteers, insomnia patients exhibited longer sleep latency and shorter total sleep duration. While the two groups had no significant differences in BMI, insomniacs presented with more N1 but less time spend in SWS and rapid eye movement sleep (REMS). Based on their SWS time, we divided insomnia patients into three groups: short (26.99±13.88), intermediate (59.24±8.12), and long (102.21±26.17) SWS groups. The short-SWS group had significantly greater BMI than the long-SWS group. Further analyses with multiple linear regression showed a significant negative correlation between the amount of SWS and BMI scores in insomniacs, whereas no such correlation was found in healthy volunteers after controlling for potential confounds (e.g., age, sex and AHI). Our study suggests that low amounts of SWS may be associated with higher BMI in patients with insomnia.  相似文献   
39.
目的:探讨胎儿咽、食管肌层中α-平滑肌肌动蛋白(α-smouth muscle actin,α-SMA)、肌球蛋白重链Ⅱ(myosin heary chain-Ⅱ、MHC-Ⅱ)、MHC-Ⅰ表达及其空间分布。方法:采用免疫组织化学SABC法及蛋白印迹法对20例胎儿咽、食管的α-SMA、MHC-Ⅰ、MHC-Ⅱ表达进行观察。结果:MHC-Ⅱ和MHC-Ⅰ共定位食管上、中段肌层,并主要表达在外部纵行肌,由上至下逐渐减少,至食管下段消失。而α-SMA则在食管上端内层肌开始表达,呈环行排列,由上至下逐渐增加,并由内肌层扩展到外肌层。结论:α-SMA、MHC-Ⅰ、MHC-Ⅱ共存于胎儿食管上中段,骨骼肌和平滑肌的移行呈渐进性,无明确界线。  相似文献   
40.
目的:探讨培哚普利防治糖尿病血管并发症的作用机制。方法:用反转录-聚合酶链反应(RT-PCR)和Northern印迹杂交方法测定0.1,1.0,10.0μmol/L浓度的培哚普利对经体外制备的糖基化终产物(AGEs)培养的人脐静脉内皮细胞(HUVECs)转化生长因子βⅡ受体(TβRⅡ)和Ⅰα(Ⅳ)前胶原mRNA表达的影响。结果:AGEs组TβRⅡ及Ⅰα(Ⅳ)前胶原mRNA表达较正常对照组明显增高(P<0.01);与AGEs组相比,TβRⅡ和Ⅰa(Ⅳ)前胶原mRNA的表达在培哚普利组0.1μmol/L时无明显降低,1.0μmol/L时分别降低了16%和10%,差异无统计学意义;10.0μmol/L时分别降低46%和50%,差异有统计学意义(P<0.05)。结论:培哚普利通过抑制高糖所致的TβRⅡ的表达,从而抑制细胞外基质的生成,防止血管重构,可能是其防治糖尿病血管并发病的机制之一。  相似文献   
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