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991.
肠球菌属产酶耐药基因研究   总被引:1,自引:4,他引:1  
目的为了解肠球菌属产酶耐药基因存在状况. 方法 20株肠球菌属进行了β-内酰胺酶TEM基因、氨基糖苷类修饰酶aac(6′)/aph(2″)和aph(3′)-Ⅲ基因和红霉素甲基化酶ermB基因检测. 结果 20株肠球菌属中有9株表型为青霉素/阿莫西林耐药并均检出TEM基因;12株对高浓度庆大霉素耐药并均检出aac(6′)/aph(2")和(或)aph(3′)-Ⅲ基因;19株耐红霉素肠球菌中,12株检出ermB基因;肠球菌中产β-内酰胺酶、氨基糖苷类修饰酶、红霉素甲基化酶的基因检出率均>50%. 结论肠球菌属耐药率已较高,且多数耐药菌已同时获得3~4个耐药基因.  相似文献   
992.
刘盈盈  易兴阳  王淳  张标  林静 《西部医学》2019,31(6):883-888
【摘要】 目的 探讨环氧合酶(COX)代谢通路基因多态性及其与缺血性卒中发病率的关系。方法 将2013年2月~2015年11月在德阳市人民医院和温州医科大学第三附属医院神经内科住院经头颅CT和MRI检查确诊的299例急性缺血性卒中患者,根据彩超结果分为颈动脉易损斑块组(VP)94例、稳定斑块组(SP)74例和无斑块组(NP)131例;同时再分为颈动脉内膜增厚组(IT)108例和非内膜增厚组(NT)191例。使用聚合酶链反应和质谱分析测定基因多态性,包括前列腺素合酶1(PTGS1 rs1236913)、前列腺素H合酶2(PTGS2 rs689466)、血栓素A2合酶(TBXAS1 rs2267679、rs41708、rs194149)、前列腺素E合酶(PTGES2 rs6478818)、环前列腺素合成酶(PTGIS rs5602、rs5629)。结果 在易损斑块组和无斑块组之间TBXAS1 rs194149 GG基因型(P=00281),PTGIS rs5602 CT基因型(P=00319)存在显著差异。内膜增厚组和非内膜增厚组之间PTGS2 rs689466 GG基因型(P=00216)显示显著差异。多元回归分析显示,PTGIS的AA基因型(P=00308,OR:0275,95%CI:0079~0955)和PTGS2的AG+ GG基因型(P=00065,OR:2162,95%CI:1232~3795)是内膜增厚的破坏性因素。结论 COX的单核苷酸多态性(SNP)与脑梗死的发病率存在相关性,PTGIS和PTGS2基因多态性与内膜增厚脑卒中患者相关。  相似文献   
993.
罗栩伟  李艳  冯刚  苟林  白亦光  杨飞  刘康  陈竹 《西部医学》2019,31(9):1364-1368+1374
【摘要】 目的 探讨腺病毒介导的GDF 5基因对人退变髓核细胞外基质表达的影响,探求一种基因治疗新途径。方法 利用腺病毒载体将GDF 5基因导入退变髓核细胞,设置为空白对照组(Control组)、阴性对照组(GFP组)、实验组(GDF 5组)3组,并分为3、7、14、21天四个观察时间点,分别检测3组髓核细胞sGAG、Hyp的含量,免疫染色、Safranine O染色观察细胞外基质合成情况,Real time PCR检测Aggrecan、Collagen II mRNA表达水平。结果 GDF 5组髓核细胞sGAG/DNA、Hyp/DNA均在14、21天较Control组和GFP组明显增加,差异有统计学意义(P<0.05),而Control组与GFP组之间任意观察时间点比较差异均无统计学意义(P>0.05);免疫染色、Safranine O染色结果显示GDF 5组髓核细胞的蛋白多糖、Ⅱ型胶原、蛋白聚糖在14、21天均呈强阳性染色,Control组和GFP组呈弱阳性染色。Real time PCR结果显示GDF 5组Aggrecan、Collagen II mRNA的表达在14、21天较Control组和GFP组明显增加,差异有统计学意义(P<0.05)。结论 腺病毒介导的GDF 5能明显促进人退变髓核细胞Aggrecan、Collagen II mRNA的表达,并增加蛋白多糖、Ⅱ型胶原的合成,对细胞外基质具有明确的修复作用,是一种有效的基因治疗新方法。  相似文献   
994.

目的:探讨中国东北地区汉族人群中年龄相关性黄斑变性(ARMD)与转铁蛋白受体2(TFR2)基因单核苷酸多态性的相关性。

方法:选取200例ARMD患者(干性100例,湿性100例)和100名健康志愿者(对照组),采集所有研究对象的外周静脉血并以EDTA抗凝处理,提取基因组DNA,根据相关文献提供的引物序列,扩增TFR2基因多态性位点rs2075674,进行聚合酶链式反应(PCR)。比较各组间的基因型频率,并按照Hardy-Weinberg平衡原理确定样本的群体代表性。

结果:TFR2基因的多态性位点rs2075674 ARMD组与对照组比较有差异(χ2=6.494,P=0.011); 湿性ARMD组与对照组比较有差异(χ2=11.054,P=0.001),而干性ARMD组与对照组无差异(χ2=1.418,P=0.234)。

结论:中国东北地区汉族人群中TFR2基因多态性rs2075674与ARMD具有相关性,且与湿性ARMD相关性较大。  相似文献   

995.
AIM: To investigate the association between interleukin-10 (IL-10) genetic polymorphisms and risk of POAG through a case-control study in a Han population of China. METHODS: A total of 210 patients with POAG and 420 normal subjects were recruited during the period from Dec. 2013 to Dec. 2016. The IL-10 -1082A>G (rs1800870), -819T>C (rs1800871) and -592C>A (rs1800872) polymorphisms were determined using iPlex GOLD SNP genotyping analysis (the SequenomMassARRAY® System, Sequenom, San Diego, USA). The association between IL-10 -1082A>G (rs1800870), -819T>C (rs1800871), and -592C>A (rs1800872) polymorphisms and risk of POAG was assessed by singlelogistic regression analysis. RESULTS: We observed that those carrying the CC genotype of rs1800871 was associated with an increased risk of POAG when compared with those harboring the TT genotype (OR=1.84, 95%CI=1.01-3.38). Those with AA genotype of rs1800872 had a 10.62 fold risk of POAG in comparison to the CC genotype (OR=10.62, 95%CI, 3.41-33.09). A completely linkage disequilibrium was found between IL-10 rs1800871-rs1800872 (D’=1.00, r2=0.16). The A-C-A (OR=2.60, 95%CI, 1.48-4.58) and G-T-A (OR=2.34, 95%CI, 1.42-3.86) haplotypes were associated with an increased risk of POAG, while the A-T-C haplotype showed a decreased risk of POAG (OR=0.63, 95%CI, 0.49-0.81). CONCLUSION: Our data suggest that IL-10 rs1800871 and rs1800872 can be predictive factors for the pathogenesis of POAG in the Chinese population.  相似文献   
996.
目的 探讨白细胞介素-10(IL-10)基因位点-1082A/G、-819C/T和-592C/A多态性与IL-10水平及儿童肠道病毒71型(EV71)感染程度的关系。方法 选取EV71感染的手足口病患儿137例为研究对象,其中轻症组91例,重症组46例,另选取行健康体检儿童122例为健康对照组,采集临床数据。采用酶联免疫吸附试验(ELISA)检测血清IL-10水平。采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)分析技术检测IL-10基因位点-1082A/G、-819C/T和-592C/A的多态性。结果 与健康对照组相比,EV71感染组患儿的-1082位点AA基因型频率和A等位基因频率更高(P < 0.05)。在EV71感染组中,重症组-1082位点AA基因型频率和A等位基因频率高于轻症组(P < 0.05)。两组间IL-10基因位点-819C/T和-592C/A多态性的分布比较差异均无统计学意义(P > 0.05)。重症组患儿血清IL-10水平明显高于轻症组和健康对照组(P < 0.05)。IL-10-1082 AA基因型、-819 TT基因型和-592 AA基因型与IL-10的低表达有关(P < 0.05)。在单倍型构建上,EV71感染组GCC单倍型的频率低于健康对照组(P < 0.05)。在EV71重症感染组中,ATA单倍型患儿的IL-10水平较其他单倍型显著降低,而GCC患儿的IL-10水平较其他单倍型显著升高(P < 0.05);轻症组和健康对照组各单倍型间的IL-10水平比较差异无统计学意义(P > 0.05)。结论 IL-10基因多态性与IL-10表达水平及EV71感染严重程度有关。  相似文献   
997.
998.
The overexpression of cyclooxygenase-2 (COX-2) was correlated with the invasion and lymphatic metastasis and with the clinical stage of Nasopharyngeal carcinoma (NPC). The C allele of COX-2 gene rs5275 polymorphism disrupts miR-542-3p function to promote COX-2 overexpression. To examine the role of COX-2 gene rs5275 polymorphism in NPC, we determined COX-2 gene rs5275 polymorphism by using a custom-by-design 48-Plex single nucleotide polymorphism (SNP) Scan? Kit. We found that C allele or CC genotype of rs5275 polymorphism in COX-2 gene was associated with an increased risk of NPC. In stratified analyses, COX-2 gene rs5275 polymorphism was associated with the risk of NPC among females, smokers, and drinkers. Based on these results, we concluded that COX-2 gene rs5275 variant contributes to NPC risk in a Chinese population. Larger studies with more diverse ethnic populations are needed to confirm these results.  相似文献   
999.
Fetal growth restriction (FGR) is a leading cause of perinatal morbidity and mortality. FGR pregnancies are often associated with histological evidence of placental vascular thrombosis. The proteoglycans are important components and regulators of vascular homeostasis. Previous studies from our laboratory highlighted mRNA and protein expression differences in placental proteoglycan decorin (DCN), within a clinically well-characterised cohort of third-trimester idiopathic FGR compared with gestation-matched uncomplicated control pregnancies. We also showed that decorin contributes to abnormal angiogenesis and increased thrombin generation in vitro. These observations suggest that DCN gene expression may contribute to the etiology of FGR. Small for gestational age (SGA) is frequently used as a proxy for FGR and is defined as a birth weight below the 10th percentile of a birth weight curve. We therefore made use of a unique resource of first trimester tissues obtained via chorionic villus sampling during the first trimester to investigate the temporal relationship between altered DCN expression and any subsequent development of SGA. We hypothesized that placental DCN expression is decreased early in gestation in SGA pregnancies. Surplus chorionic villus specimens from 15 women subsequently diagnosed with FGR and 50 from women with uncomplicated pregnancies were collected. DCN mRNA and DCN protein were determined using real-time PCR and immunoblotting, respectively. Both DCN mRNA and protein were significantly decreased in placentae from first-trimester SGA-pregnancies compared with controls (p < 0.05). This is the first study to report a temporal relationship between altered placental DCN expression and subsequent development of SGA.  相似文献   
1000.
Mechanical loading is an essential environmental factor in skeletal homeostasis, but the response of osteoblast-associated genes to mechanical osteogenic signal is largely unknown. This study uses our recently characterized in vivo osteoinductive model to analyze the sequence of stimulation and the time course of expression of osteoblast-associated genes in mechanically loaded mouse periodontium. Temporal pattern of regulation of osteocalcin (OC), alkaline phosphatase (ALP), and type I collagen (collagen I) was determined during mechanically-induced osteoblast differentiation in vivo, using a mouse tooth movement model earlier shown to induce bone formation and cell-specific regulation of genes in osteoblasts. The expression of target genes was determined after 1, 2, 3, 4, and 6 days of orthodontic movement of the mouse first molar. mRNA levels were measured in the layer of osteoblasts adjacent to the alveolar bone surface, using in situ hybridization and a relative quantitative video image analysis of cell-specific hybridization intensity, with non-osseous mesenchymal periodontal cells as an internal standard. After 24 hours of loading, the level of OC in osteoblasts slightly decreased, followed by a remarkable 4.6-fold cell-specific stimulation between 1 and 2 days of treatment. The high level expression of OC was maintained throughout the treatment with a peak 7-fold stimulation at day 4. The expression of collagen I gene was not significantly affected after 1 day, but it was stimulated 3-fold at day 2, and maintained at a similar level through day 6. The ALP gene, which we previously found to be mechanically stimulated during the first 24 hours, remained enhanced from 1.8- to 2.2-fold throughout the 6 days of treatment. Thus, in an intact alveolar bone compartment, mechanical loading resulted in a defined temporal sequence of induction of osteoblast-associated genes. Stimulation of OC 48 h after the onset of loading (and 24 h prior to deposition of osteoid) temporally coincided with that of collagen I, and was preceded for 24 h by an enhancement of ALP. Identification of OC as a mechanically responsive gene induced in functionally active osteoblasts in this study is consistent with its potential role in limiting the rate of mechanically-induced bone modeling. Furthermore, these results show that temporal progression of mechanically-induced osteoblast phenotype in this in vivo model occurs very rapidly. This suggests that physiologically relevant mechanical osteoinductive signal in vivo is targeting a population of committed osteoblast precursor cells that are capable of rapidly responding by entering a differentiation pathway and initiating an anabolic skeletal adaptation process.  相似文献   
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