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1.
目的探讨SNHG6对急性心肌梗死(AMI)小鼠左心室心肌的影响。 方法将30只雄性C57/BL6小鼠构建成AMI小鼠后随机均分为AMI组、AMI+SNHG6组、AMI+miR-101-3p组、AMI+SNHG6+miR-101-3p组、AMI+miR-101-3p+TGFBR1组,另设正常小鼠6只为假手术组。qRT-PCR检测AMI小鼠SNHG6、miR-101-3p表达水平。心脏彩超检测各组小鼠左室射血分数(LVEF);马松和天狼星红染色法以及免疫组化分析各组小鼠左心室心肌纤维化变化。将H9C2细胞株分为阴性对照组(转染空质粒)、SNHG6组(转染质粒SNHG6)、miR-101-3p组(转染质粒miR-101-3p)。Western blotting检测各组TGFBR1蛋白表达;采用双荧光素酶报告基因法预测并验证SNHG6/miR-101-3p/TGFBR1荧光素酶活性及调控机制。 结果AMI小鼠较假手术组SNHG6表达显著增加,miR-101-3p降低(P<0.05)。与AMI组比较,AMI+SNHG6组小鼠LVEF降低,心肌纤维化程度加重(P<0.05);AMI+miR-101-3p组LVEF升高,心肌纤维化程度减轻(P<0.05)。AMI+SNHG6+miR-101-3p组较AMI+SNHG6组LVEF升高、心肌纤维化程度减轻(P<0.05),而AMI+miR-101-3p+TGFBR1组较AMI+miR-101-3p组LVEF降低、心肌纤维化程度加重(P<0.05)。双荧光素酶报告基因法验证显示,miR-101-3p组SNHG6、TGFBR1野生型质粒的荧光素酶活性较阴性对照组明显降低(P<0.05)。 结论SNHG6抑制miR-101-3p上调TGFBR1加重AMI小鼠左心室心肌纤维化。  相似文献   
2.

Background

TONSL has been suggested to function as an oncogene in lung, esophageal and cervical cancer. This study was aimed to identify the expression of TONSL and its role in hepatocellular carcinoma (HCC).

Methods

By data mining in the Cancer Genome Atlas (TCGA) and Human Protein Atlas (HPA) databases, the expression profile of TONSL, its clinical significance, the potential mechanisms of its dysregulation and its underlying biological function in HCC were investigated.

Results

TONSL was significantly upregulated in HCC tissues relative to normal liver tissues (P?<?0.05). High TONSL expression was significantly correlated with advanced TNM stage, poorly differentiated tumors, vascular invasion, elevated serum alpha-fetoprotein expression and a worse prognosis (all P?<?0.05). Multivariate analysis further confirmed that TONSL overexpression was an independent risk factor for poor overall survival (OS) and recurrence-free survival (RFS) in HCC (all P?<?0.05). Additionally, 16% of HCC cases (n?=?370) had TONSL DNA amplification. The total methylation level of TONSL was moderately and negatively correlated with its mRNA expression (P?<?0.05). TONSL was predictively targeted by miR-133b, which was downregulated in HCC and negatively related to TONSL mRNA expression (all P?<?0.05). Kaplan-Meier analyses demonstrated that low miR-133b expression was significantly associated with poor OS and RFS (all P?<?0.05). Moreover, gene set enrichment analysis revealed that cases with TONSL overexpression were enriched in cell cycle regulation pathways (all P?<?0.05).

Conclusions

TONSL holds promise for serving as a prognostic biomarker for HCC. DNA amplification, hypomethylation and miR-133b downregulation could be the mechanisms associated with TONSL upregulation in HCC. TONSL might function as an oncogene via cell cycle regulation pathways in HCC.  相似文献   
3.
In a 26-wk double-blind controlled study of 34 patients whose asthma had been poorly controlled despite oral steroids, valuable clinical and pulmonary function improvement was derived by adding beclomethasone aerosol to the prednisone regimen. The amount of improvement correlated linearly with beclomethasone dosage over the range 200 to 1,600 microng/day. These patients required relatively high dosage. Success in achieving asymptomatic status was only 26% with the conventional 400 microng/day and 60% at 1,600 microng/day. Oropharyngeal candidiasis was also dose-related but did not prohibit the use of high-dosage beclomethasone. Respiratory infections, physical signs, blood glucose, and electrolytes were unaffected by the drug. A dose-related suppression of cortisol secretion was demonstrated, but about 1/4 of the group had normal plasma cortisol even at 1,600 microng/day plus the oral prednisone. An individualized risk-benefit assessment seems a better basis for choosing an optimal beclomethasone regimen for each patient than adherence to a conventionalized fixed dosage of 400 microng/day. This requires definition of: (1) a specific goal of treatment in the individual patient and the beclomethasone dosage required to achieve it; (2) the adrenocortical functional response of that particular patient to the desired dose of beclomethasone; and (3) the presence and degree of any dose-limiting constraints such as preexisting complications of steroid use.  相似文献   
4.
BackgroundEmerging evidence reveals the importance of long non-coding RNAs (lncRNAs) in the development and progression of keloid formation. However, the roles and molecular mechanism of lncRNA LINC01116 in the progression of keloid formation remain largely unknown.MethodsThe expression levels of LINC01116, microRNA-203 (miR-203) and SMAD family member 5 (SMAD5) were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Cell proliferation, migration and invasion were detected by Cell counting Kit-8 (CCK-8) assay and transwell assay. Flow cytometry and western blot assay were used to examine cell apoptosis and extracellular matrix (ECM) production. The interaction between miR-203 and LINC01116 or SMAD5 was predicted by bioinformatics analysis and verified by dual-luciferase reporter and RNA Immunoprecipitation (RIP) and RNA pull-down assays.ResultsLINC01116 and SMAD5 were upregulated while miR-203 was downregulated in keloid tissues and keloid fibroblasts. LINC01116 knockdown suppressed the proliferation, migration, invasion, and ECM production but induced apoptosis in keloid fibroblasts through enhancing miR-203 and inhibiting SMAD5. Moreover, SMAD5 was identified as a direct target of miR-203 and miR-203 could directly bind to LINC01116. Besides, LINC01116 regulated SMAD5 expression by targeting miR-203.ConclusionDownregulation of LINC01116 inhibited the progression of keloid formation by regulating miR-203/SMAD5 axis, which might provide a novel target for keloid therapy.  相似文献   
5.
石洪洋  董慧  刘嘉  崔笑天  郭毅  洪兰 《中草药》2023,54(24):8117-8126
目的 通过构建H2O2诱导的H9c2细胞氧化应激模型,观察人参皂苷Rg1对氧化应激的抑制作用,并探讨mi R-499c是否参与人参皂苷Rg1抑制氧化应激的作用机制。方法 采用600μmol/L的H2O2诱导H9c2细胞氧化应激模型,给予人参皂苷Rg1预处理24 h,检测乳酸脱氢酶(lactate dehydrogenase,LDH)、超氧化物歧化酶(superoxide dismutase,SOD)活性及丙二醛(malondialdehyde,MDA)、活性氧(reactive oxygen species,ROS)水平和线粒体膜电位(mitochondrial membrane potential,MMP)变化;采用Western blotting检测凋亡相关蛋白表达。采用Lipofiter 3.0将miR-499c转染至H9c2细胞再制备H2O2诱导的氧化应激模型,给予人参皂苷Rg  相似文献   
6.
Thirty-eight subjects who met criteria for the DSM-III-R diagnosis late luteal phase dysphoric disorder (LLPDD) were compared with 18 controls in 5-HT uptake kinetics of the platelets in the premenstrual (day 26) as well as in the postmenstrual phase (day 4) of the cycle. Furthermore, 5-hydroxytryptophan (5-HTP) was administered to LLPDD patients and controls in both phases of the cycle, to investigate pituitary sensitivity for serotonin. Plasma samples for the measurement of cortisol and -endorphin were taken before and after oral administration of 200 mg 5-HTP, and considered as an index of pituitary-adrenal function. LLPDD was not associated with a lower platelet 5-HT uptake and content in the premenstrual phase of the cycle, compared with the postmenstrual phase. Patients appeared not to be different from controls in 5-HT uptake kinetics of platelets in the premenstrual phase of the cycle. No main differences were observed between LLPDD patients and controls in their ability to respond with secretion of cortisol and -endorphin to 5-HTP stimulation, either in the premenstrual, or in the postmenstrual phase. This observation could not be attributed to differences in 5-HTP metabolism. The findings of the present study do not support a specific role for 5-HT in the pathophysiology LLPDD.  相似文献   
7.
【摘要】 目的 探讨长链非编码RNA TUSC8调控miR 137对宫颈癌迁移和侵袭的影响及其机制。方法 qPCR检测TUSC8和miR 137在宫颈癌组织和正常宫颈组织中的表达情况及差异,分析TUSC8与宫颈癌患者临床病理学参数之间的相关关系,双荧光素酶报告基因检测TUSC8与miR 137之间的相互作用;Transwell侵袭实验检测抑制TUSC8后宫颈癌细胞侵袭行为的变化情况;划痕愈合实验检测抑制TUSC8后宫颈癌细胞迁移行为的变化情况;裸鼠体内成瘤实验抑制TUSC8后宫颈癌细胞的成瘤能力的变化。结果 与正常宫颈组织相比,宫颈癌组织中TUSC8和miR 137的表达水平均相对上调,差异有统计学意义(P<005);TUSC8的表达与宫颈癌的病理分期相关以及淋巴结转移情况有关,分期越高,TUSC8在宫颈癌组织中表达越高,淋巴结转移的患者中TUSC8的表达也相对较高;双荧光素酶实验证实TUSC8能与miR 137的3’ UTR特异性结合,可以调控miR 137的表达与活性;抑制TUSC8的表达后可以抑制宫颈癌细胞的迁移和侵袭能力;抑制TUSC8后宫颈癌细胞的成瘤能力受到相应的抑制。结论 TUSC8可以调控miR 137的表达影响宫颈癌细胞的迁移和侵袭行为。  相似文献   
8.
【目的】观察miR-34a在低氧诱导的大鼠肺动脉平滑肌细胞增殖中的作用并探讨其可能的机制。【方法】原代分离和培养大鼠肺动脉平滑肌细胞(PASMC),并给予3%低氧处理后,用Real-time PCR法检测miR-34a和Notch1mRNA在大鼠PASMC中的表达;低氧条件下用细胞转染法过表达和抑制miR-34a、沉默Notch1基因的表达后用EDU法观察细胞增殖情况,并用Real-time PCR和Western blot法检测细胞核增殖抗原PCNA的表达。【结果】分离和培养大鼠PASMC并给予3%低氧处理后,大鼠PASMC中miR-34a表达明显降低,且低氧48h降低较明显,组间差异有统计学意义(P<0.05)。而Notch1的表达明显增高,且48h增高较明显,组间差异有统计学意义(P<0.05)。此外,过表达miR-34a和沉默Notch1后会显著抑制低氧引起的细胞增殖,抑制miR-34a的表达后则会促进细胞增殖,且组间差异有统计学意义(P<0.05)。【结论】在低氧诱导的PASMC细胞增殖过程中miR-34a参与了PASMC的增殖过程,且可能是通过上调Notch1引起了细胞增殖。  相似文献   
9.
目的:探讨miR-361-5p对肾细胞癌ACHN细胞增殖、侵袭、迁移、凋亡及其细胞周期的影响。方法:将miR-361-5p mimics和miR-361-5p inhibitor分别转染至肾癌ACHN细胞中,用qPCR检测转染细胞中miR-361-5p的表达水平,用MTT法、划痕愈合实验、Transwell实验、流式细胞术分别检测细胞的增殖、迁移、侵袭、细胞周期和凋亡水平。结果:与空白对照组和 Mimics-NC组比较,miR-361-5p mimics组ACHN细胞中miR-361-5p表达水平显著升高(P<0.01),细胞的增殖、侵袭和迁移能力均显著减弱(均P<0.01),而凋亡率升高(P<0.01)。与空白对照组或Inhibitor-NC组比较,miR-361-5p inhibitor组细胞中miR-361-5p表达水平显著下降(P<0.01),细胞的增殖、侵袭和迁移能力均增强(均P<0.01),细胞周期运转加速(P<0.01),凋亡率降低(P<0.05)。结论:miR-361-5p可抑制肾癌ACHN细胞的增殖、侵袭和迁移,并诱导细胞凋亡,其在肾癌发生发展过程中发挥重要的抑制作用。  相似文献   
10.

Background

Since the introduction of the theory of tumour stem cells (TSCs), the liver cancer stem cell (LCSC)-like cells have become one of the focuses in the research on liver cancer.

Materials and methods.

In this study, CD90+ cells were applied as the possible LCSC-like cells, and the miRNA and gene expression were analyzed in the CD90+ HepG2 cells. The pilot study showed miR-548c-5p exerted potential effect on the CD90+ HepG2 cells and was thereafter applied for the further study. CD90+ HepG2 cells were assigned to miR-548c-5p mimic transfection group and control group. MTT assay was performed to detect the proliferation of CD90+ HepG2 cells. The migration and invasion abilities were examined by wound healing assay and transwell migration assay, respectively. A detection of apoptosis was performed by fluorescence microscopy.

Results

Our results showed that caspase-3 and bcl-2 were down-regulated while caspase-8 was up-regulated in the CD90+ HepG2 cells. Moreover, the miR-548c-5p transfection could down-regulate the expression of β-catenin, Tg737, bcl-2, bcl-XL, and caspase-3, inhibit the proliferation, migration and invasion and promote the apoptosis of the CD90+ HepG2 cells.

Conclusions

Our findings indicate the imbalance between apoptosis and anti-apoptosis in the LCSC-like cells, which influence the biological features of LCSC-like cells. miRNA plays a regulatory role in the LCSC-like cells among which miR-548c-5p might be a suppressor.  相似文献   
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