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目的 探讨miR-30-5p对视网膜母细胞瘤细胞增殖的影响及作用机制。 方法 采用实时荧光定量聚合酶链式反应(qRT-PCR)检测miR-30-5p在视网膜母细胞瘤细胞系和人视网膜内皮细胞(HRECs)中的表达。利用TargetScan数据库进行生物信息学分析并预测miR-30-5p靶基因,双荧光素酶报告基因实验验证miR-30-5p与FOXG1的3'UTR结合能力及靶向关系,qRT-PCR和Western blotting分别检测miR-30-5p对FOXG1的mRNA与蛋白表达影响。瞬时转染Y79细胞后,通过CCK8法检测各组Y79细胞的增殖。 结果 与HRECs比较,miR-30-5p在视网膜母细胞瘤细胞中表达降低,FOXG1在视网膜母细胞瘤细胞中表达升高。生物信息学预测结果显示miR-30-5p与FOXG1存在结合位点,qRT-PCR和Western blotting显示miR-30-5p可负调控FOXG1的mRNA和蛋白的表达,双荧光素酶实验结果证实miR-30-5p与FOXG1 3'UTR存在靶向关系。瞬时转染miR-30-5p可升高Y79细胞中miR-30-5p的表达水平,抑制Y79细胞的增殖活力。过表达FOXG1可逆转miR-30-5p上调对Y79细胞增殖的影响。 结论 miR-30-5p通过下调FOXG1表达抑制视网膜母细胞瘤Y79细胞的增殖。  相似文献   
3.
郝志晔  张晶  钱伟  卢雯平 《陕西中医》2021,(2):192-195,199
目的:研究参芪排毒汤对宫颈癌组织人乳头瘤病毒(HPV)E6/E7 mRNA、肿瘤抑制基因(P53)、视网膜母细胞瘤蛋白(PRb)表达水平的影响与意义。方法:选取112例宫颈癌患者进入研究,按随机数字表划分成对照组与治疗组,两组均给予新辅助化疗联合腹腔镜宫颈癌根治术治疗,治疗组在新辅助化疗的同时给予参芪排毒汤口服; 术前评估两组临床疗效,统计不良反应发生情况,术中取癌旁健康组织与病灶病理组织样本检测HPV E6和E7 mRNA表达水平并计算E6/E7比值,检测样本中P53、PRb表达水平; 随访至少3年,比较两组患者的3年无病情进展生存时间(PFS)、总生存时间(OS),分析新辅助化疗后病理组织中HPV E6/E7、P53、PRb表达水平对PFS、OS的预测价值。结果:治疗组缓解率为83.93%,对照组为62.50%,治疗组缓解率高于对照组(P<0.05); 治疗组不良反应发生率为12.50%,对照组为17.86%,差异比较无统计学意义(P>0.05); 化疗后两组患者癌旁组织中HPV E6/E7比值比较,差异无统计学意义(P>0.05),病理组中HPV E6/E7表达高于治疗组(均P<0.05),两组癌旁与病理组织中P53、PRb比较,差异有统计学意义(均P>0.05); 化疗后宫颈癌组织中HPV E6/E7、P53、PRb表达水平对于患者无病情进展生存时间PFS、OS均具有较高预测价值(AUC>0.9,P<0.05); 治疗组患者PFS、OS均长于对照组(均P<0.05)。结论:在腹腔镜宫颈癌根治术前新辅助化疗中联合应用参芪排毒汤,能够提高术前疗效,抑制宫颈癌组织中HPV E6/E7表达、提升P53、PRb表达水平,从而起到延长患者无病情进展生存时间与总生存时间,改善预后的作用。  相似文献   
4.
目的通过CT检查及图像后处理软件,分析视网膜母细胞瘤(RB)内钙化程度与性别、眼别、年龄、影像学分期之间的关系。方法选择经河北省眼科医院眼眶病及眼肿瘤科手术或穿刺病理证实的120例RB患者150眼进行研究。通过影像学分期将其分为4组:眼球内期组98眼,其中肿瘤内钙化87眼;青光眼期组37眼,其中肿瘤内钙化34眼;眼球外期组11眼,其中肿瘤内钙化10眼;远处转移期组4眼,其中肿瘤内钙化3眼。眼眶横断面CT薄层扫描、软组织算法重建,采用西门子Volume软件测量钙化区域容积及眼球容积。使用SPSS 22.0统计分析软件处理实验数据,分析不同性别、眼别、年龄、影像学分期间钙化区域容积(CRV)/眼球容积(EV)比值采用秩和检验。结果眼球内期组不同性别、眼别RB患者CRV/EV比值差异无统计学意义;眼球内期组RB患者不同年龄组间CRV/EV比值差异有统计学意义;两两比较后显示1岁~组肿瘤钙化程度低于2岁~组,1岁~组肿瘤钙化程度低于3岁~组,1岁~组肿瘤钙化程度低于0岁~组;青光眼期组不同性别RB患者CRV/EV比值之间进行比较,差异有统计学意义,女性高于男性;青光眼期组不同眼别RB患者CRV/EV比值进行比较,差异有统计学意义,右眼高于左眼;青光眼期组不同年龄组间RB患者CRV/EV比值进行比较,差异无统计学意义;眼球内期组与青光眼期组RB患者CRV/EV比值期别进行比较,差异有统计学意义,RB患者青光眼期肿瘤钙化程度高于眼球内期。结论RB患者钙化程度在眼球内期、青光眼期随病情进展呈上升趋势;眼球内期RB患者1岁~组肿瘤钙化程度出现低谷区。  相似文献   
5.
细胞增殖、生长和分裂等过程受到细胞周期的严格调控,其调控机制在肿瘤的发生发展中发挥重要作用。近年来,多项研究显示,细胞周期蛋白依赖性激酶4和6(CDK4/6)抑制剂对于雌激素受体阳性或人类表皮生长因子受体阳性的乳腺癌患者具有较好的疗效,然而其在三阴性乳腺癌患者中的作用仍存在争议,故探究相关分子标志物以进一步筛选最能从该治疗中获益的乳腺癌人群对临床具有重要意义。此外视网膜母细胞瘤基因(Rb)也在乳腺癌中扮演关键角色,而cyclin D-CDK4/6-Rb信号通路因具有调控细胞周期限制点的作用,被认为是乳腺癌潜在的治疗靶点。本文将对CDK4/6抑制剂在乳腺癌治疗中的研究进展作一综述。  相似文献   
6.
Cell senescence contributes to organismal aging and is induced by telomere erosion and an ensuing DNA damage signal as cells reach the end of their replicative lifespan in vitro or in vivo. Stresses induced by oncogene or tumor suppressor hyperactivation, oxidative stress, ionizing radiation and other DNA damaging agents result in forms of stress induced premature senescence (SIPS) that show similarities to replicative senescence. Since replicative senescence and SIPS occur over many days and many population doublings of the mass cultures of primary cells used to study senescence, the sequence of events that occur downstream of senescence signaling can be challenging to define. Here we compare a new model of ING1a-induced senescence with several other forms of senescence. The ING1a epigenetic regulator synchronously induces senescence in mass cultures several-fold faster than all other agents, taking 24 and 36 hours to activate the Rb/ p16INK4a, but not the p53 tumor suppressor axis to efficiently induce senescence. ING1a induces expression of intersectin 2, a scaffold protein necessary for endocytosis, altering the stoichiometry of endocytosis proteins, subsequently blocking growth factor uptake leading to activation of Rb signaling to block cell growth. ING1a acts as a novel link in the activation of the Rb pathway that can impose senescence in the absence of activating p53-mediated DNA damage signaling, and should prove useful in defining the molecular events contributing to Rb-induced senescence.  相似文献   
7.

OBJECTIVE:

To analyze the flow of retrobulbar vessels in retinoblastoma by color Doppler imaging.

METHODS:

A prospective study of monocular retinoblastoma treated by enucleation between 2010 and 2014. The examination comprised fundoscopy, magnetic resonance imaging, ultrasonography and color Doppler imaging. The peak blood velocities in the central retinal artery and central retinal vein of tumor-containing eyes (tuCRAv and tuCRVv, respectively) were assessed. The velocities were compared with those for normal eyes (nlCRAv and nlCRVv) and correlated with clinical and pathological findings. Tumor dimensions in the pathological sections were compared with those in magnetic resonance imaging and ultrasonography and were correlated with tuCRAv and tuCRVv. In tumor-containing eyes, the resistivity index in the central retinal artery and the pulse index in the central retinal vein were studied in relation to all variables.

RESULTS:

Eighteen patients were included. Comparisons between tuCRAv and nlCRAv and between tuCRVv and nlCRVv revealed higher velocities in tumor-containing eyes (p<0.001 for both), with a greater effect in the central retinal artery than in the central retinal vein (p=0.024). Magnetic resonance imaging and ultrasonography measurements were as reliable as pathology assessments (p=0.675 and p=0.375, respectively). A positive relationship was found between tuCRAv and the tumor volume (p=0.027). The pulse index in the central retinal vein was lower in male patients (p=0.017) and in eyes with optic nerve invasion (p=0.0088).

CONCLUSIONS:

TuCRAv and tuCRVv are higher in tumor-containing eyes than in normal eyes. Magnetic resonance imaging and ultrasonography measurements are reliable. The tumor volume is correlated with a higher tuCRAv and a reduced pulse in the central retinal vein is correlated with male sex and optic nerve invasion.  相似文献   
8.
BackgroundLong non-coding RNA (lncRNA) TMPO antisense RNA 1 (TMPO-AS1) is reported to be oncogenic in prostate cancer and lung cancer. This study aims to investigate the expression and biological function of it in retinoblastoma (RB), and explore its regulatory role for miR-199a-5p and hypoxia-inducible factor-1α (HIF-1α).MethodsPaired RB samples were collected, and the expression levels of TMPO-AS1, miR-199a-5p and HIF-1α were examined by quantitative real-time polymerase chain reaction (qRT-PCR); TMPO-AS1 overexpressing plasmids and TMPO-AS1 shRNA were transfected into HXO-RB44 and SO-Rb50 cell lines respectively, and then proliferation, migration and invasion of RB cells were detected by CCK-8 assay and Transwell method. qRT-PCR and western blot were used to analyze the regulatory function of TMPO-AS1 on miR-199a-5p and HIF-1α; luciferase reporter gene assay was used to determine the regulatory relationship between miR-199a-5p and TMPO-AS1.ResultsTMPO-AS1 was significantly up-regulated in cancerous tissues of RB samples (relatively expression: 2.97 vs 3.93, p < 0.001), negatively correlated with miR-199a-5p (r=-0.4813, p < 0.01). There was one binding site on TMPO-AS1 for miR-199a-5p. After transfection of TMPO-AS1 shRNAs into RB cells, the proliferation, migration and invasion of cancer cells was significantly inhibited, while TMPO-AS1 had opposite effects; TMPO-AS1 was also demonstrated to regulate the expression of HIF-1α on both mRNA and protein levels via negatively regulating miR-199a-5p.ConclusionTMPO-AS1 is abnormally up-regulated in RB tissues, and it can modulate the proliferation and migration of RB cells. It has the potential to be the “ceRNA” to regulate HIF-1α expression by sponging miR-199a-5p.  相似文献   
9.
A major advance was made to reduce the side effects of cancer therapy via the elucidation of the tumor-specific lytic path “hyperploid progression-mediated death” targeting retinoblastoma (Rb) or p53-mutants defective in G1 DNA damage checkpoint. The genetic basis of human cancers was uncovered through the cloning of the tumor suppressor Rb gene. It encodes a nuclear DNA-binding protein whose self-interaction is regulated by cyclin-dependent kinases. A 3D-structure of Rb dimer is shown, confirming its multimeric status. Rb assumes a central role in cell cycle regulation and the “Rb pathway” is universally inactivated in human cancers. Hyperploidy refers to a state in which cells contain one or more extra chromosomes. Hyperploid progression occurs due to continued cell-cycling without cytokinesis in G1 checkpoint-defective cancer cells. The evidence for the triggering of hyperploid progression-mediated death in RB-mutant human retinoblastoma cells is shown. Hence, the very genetic mutation that predisposes to cancer can be exploited to induce lethality. The discovery helped to establish the principle of targeted cytotoxic cancer therapy at the mechanistic level. By triggering the lytic path, targeted therapy with tumor specificity at the genetic level can be developed. It sets the stage for systematically eliminating side effects for cytotoxic cancer therapy.  相似文献   
10.
黄锋  胡彦卿  杨书茂  黄娇娇  周晓霞 《基层医学论坛》2013,(31):4102-4103,F0003
目的评价CT、彩色多普勒血流显像(CDFI)在视网膜母细胞瘤诊断中的价值。方法回顾性分析20例经临床和手术病理证实为视网膜母细胞瘤患者的CT、CDFI表现特点。结果20例患者均发现球后壁肿块,并伴有钙化。CT、CDFI检查分别显示不规则型软组织肿块9眼(42.85%)、7眼(33.33%),圆形或半圆形软组织肿块11眼(57.15%)、14眼(66.67%),显示有钙化斑的21眼(100%)、19眼(90.50%),显示视神经增粗的5眼(23.80%)、5眼(23.80%),显示有向眶内蔓延的3眼(9.50%)、4眼(19.47%)。结论CT及CDFI检查在视网膜母细胞瘤诊断中各有所长,具有重要的临床应用价值。  相似文献   
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