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81.
目的探讨沉默囊性纤维化跨膜传导调节因子(cystic fibrosis transmembrane conductance regulator,CFTR)在大鼠海马神经元细胞线粒体功能及氧化应激中的作用。方法18只SD大鼠随机分为CFTR小干扰RNA(small interfering RNA,siRNA)组、阴性对照组、空白对照组各6只。分离3组海马神经元细胞,取对数生长期细胞进行实验。CFTR siRNA组神经元细胞转染CFTR siRNA,阴性对照组转染阴性对照siRNA,空白对照组不转染。转染后培养48 h,采用Western blot法检测3组神经元细胞线粒体CFTR蛋白相对表达量,JC-1荧光探针检测线粒体膜电位,荧光分光光度法检测线粒体活性氧(reactive oxygen species,ROS)和过氧化氢(hydrogen peroxide,H2O2)表达,氧电极法测定线粒体呼吸控制率(respiratory control rate,RCR),荧光素酶发光法检测线粒体三磷酸腺苷(adenosine triphosphate,ATP)浓度,高效液相色谱法检测线粒体谷胱甘肽(glutathione,GSH)和氧化型谷胱甘肽(oxidized glutathione,GSSG)表达。结果转染后培养48 h,CFTR siRNA组神经元细胞线粒体CFTR蛋白相对表达量(0.09±0.01)、线粒体膜电位[(247.16±34.28)mV]、ATP[(11.71±2.54)mol/g]、RCR(4.69±0.82)、GSH[(0.71±0.12)nmol/μg]、GSH/GSSG值(0.31±0.08)低于空白对照组[0.42±0.07、(432.18±56.04)mV、(24.18±3.64)mol/g、7.94±1.21、(1.62±0.23)nmol/μg、1.65±0.27]和阴性对照组[0.38±0.06、(434.07±52.13)mV、(22.97±3.43)mol/g、7.83±1.18、(1.57±0.21)nmol/μg、1.63±0.24](P<0.05),线粒体H2O2水平(1.73±0.11)高于空白对照组(1.00±0.02)和阴性对照组(1.08±0.06)(P<0.05);空白对照组神经元细胞线粒体CFTR蛋白相对表达量及线粒体膜电位、ATP、RCR、H2O2、GSH、GSH/GSSG值与阴性对照组比较差异均无统计学意义(P>0.05)。结论沉默大鼠神经元细胞线粒体CFTR可引起海马神经元细胞线粒体功能障碍,增强氧化应激反应。  相似文献   
82.
Bone marrow‐derived mesenchymal stromal cells (MSCs) have been wildly applied to cell‐based strategies for tissue engineering and regenerative medicine; however, they have to undergo the senescence process and thus appeared to be less therapeutic effective. HMGA2, a protein belonged to high mobility group A (HMGA) family, exhibits an inverse expression level related to embryonic development and acts as a developmental regulator in stem cell self‐renewal progression. Therefore, we performed senescence‐associated β‐galactosidase (SA‐β‐gal) staining, transwell assay, to examine the changes of MSCs in different stages and then over‐expressed HMGA2 in MSCs by lentivirus transfection. We found the percentage of SA‐β‐gal staining positive cells in MSCs from 24‐month‐old Sprague–Dawley (SD) rats (O‐MSCs) was significantly higher compared with MSCs from 2‐week‐old SD rats (Y‐MSCs), and the expression levels of P21 and P53, two senescence‐related molecules, were also significantly up‐regulated in O‐MSCs than in Y‐MSCs. In contrast, the HMGA2 expression level in O‐MSCs was dramatically down‐regulated in contrast to Y‐MSCs. In additional, the migration ability in O‐MSCs was significantly attenuated than in Y‐MSCs. After successfully over‐expressed HMGA2 in O‐MSCs, the percentage of SA‐β‐gal staining positive cells and the expression levels of P21 and P53 were reduced, and the migration ability was improved compared with O‐MSCs without treatment. Further, mRNA sequencing analysis revealed that overexpression of HMGA2 changed the expression of genes related to cell proliferation and senescence, such as Lyz2, Pf4, Rgs2, and Mstn. Knockdown of Rgs2 in HMGA2 overexpression O‐MSCs could antagonize the protective effect of HMGA2 in the senescence process of O‐MSCs.  相似文献   
83.
目的 探讨反义微小RNA-21寡核苷酸(antisense oligonucleotide micro RNA-21,AS-miRNA-21)抑制Tb3.1人舌鳞状细胞癌增殖的效果和机制.方法 实验分3组,①空白对照组;②无义寡核苷酸转染组;③AS-miRNA-21转染组.寡核苷酸介导转染反义寡核苷酸敲低Tb3.1细胞miRNA-21表达.使用荧光实时定量聚合酶链反应(PCR)鉴定转染后Tb 3.1细胞miRNA-21表达水平;甲基噻唑基四唑(MTT)法检测转染后Tb 3.1细胞生存率;流式细胞术检测转染后Tb3.1早期凋亡;Matrigel基质生长实验检测转染后Tb 3.1细胞生长形成球形集落能力;Transwell体外迁移实验检测转染后Tb 3.1细胞迁移能力;蛋白质印迹法检测转染后Tb3.1细胞增殖核抗原(antigen KI-.67,Ki67)、B细胞淋巴瘤2(B cell lymphoma 2,Bcl-2)、人第10号染色体缺失的磷酸酶及张力蛋白同源的基因(phosphatase and tensin homolog,PTEN)、基质金属蛋白酶2、9(matrix metalloproteinase 2/9,MMP-2、MMP-9)和组织基质蛋白酶抑制因子蛋白1(tissue inhibitor of metalloproteinase 1,TIMP-1)蛋白表达.结果 荧光实时定量PCR显示转染后miRNA-21表达水平下调;转染第4天,AS-miRNA-21转染组肿瘤细胞生长速度[(53.43±11.83)%]低于其他两组[(91.32±8.02)%和100%](F=27.02,P=0.00);细胞凋亡率显著升高[(12.23±2.92)%,F=26.641,P=0.001];AS-miRNA-21转染组细胞生长不能形成球形克隆且通过Transwell小室聚碳酸酯膜的细胞数小于空白对照组(F=268.231,P=0.000);Ki67、Bcl-2、MMP-2和MMP-9蛋白表达下调,PTEN和TIMP-1蛋白表达上调.结论 敲低miRNA-21后Tb3.1人舌癌细胞增殖与侵袭能力被抑制,并为探索miRNA-21调控人舌癌发生机制提供实验依据.
Abstract:
Objective To investigate the effect of micro RNA-21 (miRNA-21) knocking on the Tb3.1 human tongue squamous cell carcinoma growth. Methods Anti-sense miRNA-21 oligonucleotide was delivered with oligofectamine to suppress Tb 3. 1 tongue cancer cell growth in vitro. Real-time polymerase chain reaction (PCR) was conducted to detect the miRNA-21 expression after transfection. Methyl thiazolyl tetrazolium(MTT) assay was used to determine Tb 3. 1 cell survival rate. Apoptosis were examined by flowcytometry. Matrigel matrix and transwell assay were used to determine Tb 3.1 cell colony formation and migration ability. Antigen KI-67 (Ki67), B cell lymphoma (Bcl-2), phosphatase and tensin homolog (PTEN), matrirx metalloproteinase 2(MMP-2, MMP-9) and tissue inhibitor of metalloproteinase 1 (TIMP-1) protein expression in Tb 3. 1 cell were measured by Western blotting. Results miRNA-21 expression was decreased in miRNA-21 antisense oligonucleotide (ASODN) group. The survival rate of Tb 3. 1 cells with AS-miRNA-21 transfection was significantly suppressed (F=27.02, P = 0.00) and early phase apoptosis(F =26. 641 ,P = 0. 001) induced in Tb 3.1 cell. Ki67, Bcl-2, MMP-2 and MMP-9 protein weredown regulated while PTEN and TIMP-1 protein expression was increased. Conclusions Blocking miRNA-21 expression in Tb3.1 cell could suppress cancer cell growth in vitro and miRNA-21 can serve as a novel target candidate for human tongue cancer gene therapy.  相似文献   
84.
 目的:研究肌原纤维形成调节因子1 (MR-1)是否通过抑制蛋白激酶R样内质网激酶 (PERK)/核因子E2相关因子2(Nrf2)途径减轻缺氧/复氧 (H/R)诱导的心肌细胞凋亡。方法:在原代培养的乳大鼠心肌细胞H/R模型上,采用Annexin V/PI双标法检测心肌细胞的凋亡率;以Western blotting检测葡萄糖调节蛋白78 (GRP78)、磷酸化PERK、Nrf2、活化转录因子4 (ATF4)、C/EBP同源蛋白 (CHOP)、Bcl-2和Bax的蛋白水平,研究过表达或敲低对于H/R致心肌细胞凋亡的影响及其与PERK/Nrf2途径活化的关系。结果:H/R引起心肌细胞凋亡;过表达MR-1减轻H/R引起的细胞凋亡 (P<0.01),下调CHOP表达 (P<0.05),引起Bcl-2/Bax值升高 (P<0.01),并抑制H/R诱导的PERK磷酸化、Nrf2核转位和ATF4表达 (P<0.01)。敲低MR-1加重H/R引起的细胞凋亡 (P<0.01)、CHOP表达上调 (P<0.05)和Bcl-2/Bax值下降 (P<0.01),并加重H/R诱导的PERK磷酸化 (P<0.05)、Nrf2核转位和ATF4表达 (P<0.01)。结论:MR-1通过抑制PERK/Nrf2途径而减轻缺氧/复氧诱导的心肌细胞凋亡。  相似文献   
85.
86.

Background

Nephrolithiasis is a worldwide health problem that affects almost all populations. This study aimed to evaluate the association between rs12654812 of regulator of G protein signaling 14 (RGS14) gene and nephrolithiasis in the Chinese population.

Methods

A total of 1541 participators including 830 cases and 711 controls were included from Guangxi area in China. Age, sex, BMI, smoking status, drinking status, creatinine, uric acid, and urea nitrogen were analyzed between the case group and control group.

Results

We found that the G/A+A/A genotypes of rs12654812 had a significantly increased nephrolithiasis risk after adjusting age, sex, BMI, smoking, drinking, and hypertension, compared with G/G genotype (OR = 1.361, 95% CI = 1.033‐1.794, P = .029). This hazardous effect was more pronounced in subgroup of age < 50, ever smoking, ever drinking, creatinine normal, and high uric acid. The G/A genotype of rs12654812 also had a significantly increased nephrolithiasis risk compared with G/G genotype. The A allele of rs12654812 significantly increased the risk of nephrolithiasis compared with the G allele after adjusting for age, sex, BMI, smoking, drinking and hypertension (OR = 1.277, 95% CI = 1.013‐1.609, P = .038).

Conclusions

Our results suggest that the RGS14 polymorphism is involved in the etiology of nephrolithiasis and thus may be a genetic marker for nephrolithiasis.
  相似文献   
87.
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89.
Hepatitis C virus (HCV) chronic infection is associated with fibrosis progression, end-stage liver complications and HCC. Not surprisingly, HCV infection is a leading cause of liver-related morbidity and mortality worldwide. After sustained virological response (SVR), the risk of developing hepatocellular carcinoma is not completely eliminated in patients with established cirrhosis or with advanced fibrosis. Therefore, lifelong surveillance is currently recommended. This strategy is likely not universally cost-effective and harmless, considering that not all patients with advanced fibrosis have the same risk of developing HCC. Factors related to the severity of liver disease and its potential to improve after SVR, the molecular and epigenetic changes that occur during infection and other associated comorbidities might account for different risk levels and are likely essential for identifying patients who would benefit from screening programs after SVR. Efforts to develop predictive models and risk calculators, biomarkers and genetic panels and even deep learning models to estimate the individual risk of HCC have been made in the direct-acting antiviral agents era, when thousands of patients with advanced fibrosis and cirrhosis have reached SVR. These tools could help to identify patients with very low HCC risk in whom surveillance might not be justified. In this review, factors affecting the probability of HCC development after SVR, the benefits and risks of surveillance, suggested strategies to estimate individualized HCC risk and the current evidence to recommend lifelong surveillance are discussed.  相似文献   
90.
目的探讨胃癌组织中沉默信息调节因子1(SIRT-1)和血管内皮生长因子(VEGF)的表达及临床意义。方法选取2016年6月至2018年6月本院胃癌患者120例,均接受胃癌手术切除术。采用免疫组化检测胃癌组织及其癌旁正常组织中SIRT-1、VEGF的表达。结果胃癌组织SIRT-1、VEGF表达阳性率明显高于癌旁正常组织,差异有统计学意义(P<0.05);胃癌组织SIRT-1、VEGF的表达与TNM分期、浸润深度、浆膜受侵、淋巴结转移有关(P<0.05),与性别、年龄、肿瘤位置、分化程度、肿瘤直径无关(P>0.05);胃癌组织SIRT-1与VEGF表达呈正相关(P<0.05)。结论胃癌组织中SIRT-1、VEGF呈高表达状态,且与胃癌的发生发展有关,可能共同促进了胃癌的生长、侵袭、转移等生物学行为。  相似文献   
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