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961.
广西人群DNA修复基因XRCC3多态性与肝细胞癌遗传易感性关联分析 总被引:1,自引:0,他引:1
目的 探讨DNA修复基因X线修复交叉互补因子3(X-ray cross-complementing group 3,XRCC3)基因Thr241Met多态性与黄曲霉毒素B1(aflatoxin B1,AFB1)相关性肝细胞癌(hepatocellular carcinoma,HCC)遗传易感性的相关性.方法 应用PCR技术对AFB1高污染区广西地区257例HCC患者和711名对照人群的XRCC3基因多态性进行检测,进行的病例对照研究.结果 (1)XRCC3 3种基因型(Thr/Thr、Thr/Met、Met/Met)中带有Met者与HCC的易感性相关,且这种相关性与Met数量呈正相关(校正风险值OR分别为2.20和8.56);(2)XRCC3突变基因型多态与血白细胞AFB1-DNA加合物水平在HCC发生过程中存在协同作用(校正OR:2.34~20.44,P<0.01).结论 XRCC3多态性与HCC易感性相关,且这种多态性与AFB1暴露水平在HCC发生中存在协同作用. 相似文献
962.
963.
目的:探讨术前细针穿刺基因检测BRAFV600E突变丰度与甲状腺乳头状癌(papillary thyroid cancer,PTC)临床病理特征的关系。方法:回顾性统计2021年1月30日至2022年2月28日就诊于南京中医药大学附属中西医结合医院的301例患者临床资料,术前细针穿刺基因检测示BRAFV600E突变(含突变丰度检测),所有患者完成甲状腺癌根治术,术后病理证实为甲状腺乳头状癌,分析BRAFV600E基因突变丰度与临床病理特征的关系。结果:纳入301例患者,男91例,女210例,年龄42(33~51)岁,范围18~69岁。肿瘤直径>1 cm的患者BRAFV600E基因突变丰度高于肿瘤直径≤1 cm者[29.05(18.03~37.56) vs.18.35(6.74~29.61),P<0.001],颈部淋巴结转移患者BRAFV600E基因突变丰度高于无颈部淋巴结转移者[24.72(8.08~34.32) vs.18(8.68~28.54),P=0.040]... 相似文献
964.
目的:肝细胞癌预后相关的分子标志物对提高患者生存质量和改善疗效至关重要,本研究旨在探究细胞分裂周期相关基因8(cell division cycle associated 8,CDCA8)对肝细胞癌预后的影响及潜在分子机制。方法:432例肝细胞癌样本的转录组数据及对应患者的临床信息下载自肿瘤基因表达图谱(The Cancer Genome Atlas,TCGA)数据库。分析肿瘤组织和正常组织中CDCA8 mRNA差异;根据CDCA8 mRNA中位数将肝细胞癌患者分为高表达组和低表达组,绘制生存曲线。采用Kruskal检验分析CDCA8与肿瘤分期、分级和T分期的相关性。采用单因素和多因素Cox回归分析探究CDCA8能否作为肝细胞癌患者的独立预后因子。采用基因集富集分析(gene set enrichment analysis,GSEA)探究CDCA8在肝细胞癌中的潜在作用机制。结果:CDCA8在肿瘤组织中的mRNA水平明显高于正常对照组织(P<0.001),CDCA8高表达患者的生存率明显低于低表达组(P<0.001)。随着肿瘤分期(P<0.001)、分级(P<0... 相似文献
965.
目的:探究生物钟相关基因在原发性肝细胞癌(简称肝癌)中的表达及意义。方法:从美国癌症和肿瘤基因图谱数据库(The Cancer Genome Atlas,TCGA)中下载肝癌数据424例,包括374例肝癌患者样本及50例正常对照样本。运用DECenter软件对51个生物钟相关基因进行差异表达分析,比较生物钟基因在肝癌患者及正常样本之间的表达情况。运用DAVID在线工具分析差异基因的GO及KEGG功能富集通路,并通过STRING数据库构建差异基因之间蛋白质相互作用网络。了解生物钟基因肝癌发生发展过程中的主要作用。结果:在374例肝癌患者样本的51个生物钟相关基因中,有21个基因在肝癌样本中表达上调(P<0.05),3个基因表达下调(P<0.05)。生物钟基因高表达样本主要富集于Wnt信号通路、Hedgehog信号通路及Hippo信号通路(P<0.001)。参与调节昼夜节律和细胞代谢的10个生物钟基因在蛋白质相互作用网络中相关性最为紧密(P<0.001)。GO分析差异基因集中作用于调节昼夜节律、细胞代谢过程、基因表达等通路(P<0.001)。结论:生物钟相关基... 相似文献
966.
Cholecystokinin and neurotensin mRNAs are differentially expressed in subnuclei of the ventral tegmental area 总被引:1,自引:0,他引:1
Immunohistochemical studies of ventral tegmental area (VTA) neurons indicate that individual cells can contain dopamine as well as the neuropeptide neurotransmitters cholecystokinin (CCK) and neurotensin (NT). We have defined the distribution of the cells expressing the mRNAs encoding these two dopamine cotransmitter peptides in each of the subnuclei of the ventral tegmental area, and quantitated the extent of expression of each gene by using in situ hybridization methods. These studies reveal significant differences in the patterns of expression of each of these two genes within various subdivisions of the VTA. The rostral linear nucleus contained numerous CCK positive cells, some of which appeared to express preproCCK-mRNA at a very high level, but this nucleus contained relatively few NT-expressing cells. The parabrachialis pigmentosus contained numerous NT and CCK positive cells. The paranigralis and interfascicularis nuclei displayed positive CCK cells but with expression at only modest levels. NT cells were very few in these nuclei. The caudal linear nuclei contained the highest number of NT-expressing neurons and these cells expressed very high levels of NT mRNA. The selective distribution of these peptide genes within the VTA subnuclei may have specific consequences. Studies of the connectivity of neurons in the VTA show that the different subnuclei of this region project to several functionally and architectonically different regions of the cerebral cortex and subcortically to nuclei related to the limbic system. Results from our study show very prominent expression of CCK mRNAs in those subnuclei that project heavily to the prefrontal, other cortical areas, and the amygdaloid complex. The NT gene is expressed prominently in those subnuclei of VTA that project heavily to the entorhinal cortex and amygdaloid complex. These results provide support for a differential role for the NT-expressing neurons than that of CCK-expressing neurons of VTA in "reward" mechanisms and in drug-seeking and motivational behavior. These observations could be applied to create working hypotheses and experimental paradigms to test the differential functional activity of the subdivisions of VTA and their potential roles in the pathogenesis and treatment of drug-seeking behavior and other neuropsychiatric disorders. 相似文献
967.
Cloning and Characterization of the Rat Gene Encoding GAP-43 总被引:1,自引:0,他引:1
Grabczyk E Zuber MX Federoff HJ Ng SC Pack A Fishman MC 《The European journal of neuroscience》1990,2(10):822-827
968.
S fimbrial adhesins (Sfa) represent virulence factors of E. coli wild-type strains causing urinary tract infections and meningitis of the new born. In order to determine the influence of subinhibitory concentration of antibiotics on the expression of the sfa gene cluster, a wild-type strain carrying the lacZ gene, coding for the enzyme β-galactosidase fused to the sfa determinant was used. The expression of lacZ which was under the control of the sfa wild-type promoters, was now equivalent to the sfa gene expression of wild-type strain 536. With this strain the influence of subinhibitory concentrations of 28 antibiotics on the expression of the sfa determinant was studied. The expression was strongly suppressed by a treatment of the wild-type fusion strain by aztreonam, gentamicin, clindamycin and trimethoprim; the latter had a dramatic effect on sfa expression. It was further shown for clindamycin and trimethoprim that the reduction of sfa gene expression was dependent on the concentration of the antibiotics. In contrast imipinem, amphotericin B and rifampicin weakly stimulated sfa expression. We conclude that gene fusions between virulence-associated loci and indicator genes in wild-type pathogens are useful to study virulence modulation due to subinhibitory concentration of antibiotics on the genetic level. 相似文献
969.
Apolipoprotein E gene polymorphism and its association with human longevity in the Uygur nationality in Xinjiang 总被引:5,自引:0,他引:5
Objective To study the relationship between apoE alleles and life-span.Methods Apolipoprotein E genotypes were determined in 164 unrelated Uygurs including 35 persons aged 90 years or older, 71 men aged 20-35 and 54 men with myocardial in farction by using polymerase chain reaction-restriction fragment length polymor phism.Apolipoprotein E gene polymorphism was analyzed among three groups. Results There was statistically significant difference in the ε4 allele frequencies amo ng three groups.The ε4 allele frequency in olds was the lowest (0.057), whil e in patients suffering from myocardial infarction (MI) was the highest (0.213) .In MI patients the average age of first attack in ε4 allele carriers was sig nificantly younger than that of non-carries, 51.3 and 58.3 years, respectivel y (P<0.05).Conclusion ApoE genotype may have some impact on human longevity. 相似文献
970.
瘤体注射IL-2重组腺病毒基因治疗小鼠胶质母细胞瘤及其免疫机制的初步探讨 总被引:1,自引:0,他引:1
目的:观察瘤体直接注射IL-2重组腺病毒对G422皮下荷瘤的治疗作用,对体内基因转染效率及治疗的免疫机制进行初步分析。方法:将LacZ,IL-2重组腺病毒直接注射到皮下接种的G422胶质母细胞瘤瘤体,X-gal染色检测基因转染的效率,观察肿瘤的大小和荷瘤小鼠的存活期,采用4h^51Cr释放法检测荷瘤小鼠脾细胞诱导的NK、LAK、CTL的杀伤活性,对治疗后的肿瘤进行常规病理分析。结果:采用瘤体注射腺病毒具有较高的体内基因转染效率,瘤体注射IL-2重组腺病毒对皮下建立的胶质母细胞瘤有一定的治疗作用,肿瘤的生长受抑制,荷瘤小鼠的存活期显延长,但没有长期存活小鼠。IL-2基因治疗组小鼠脾细胞的LAK、CTL杀伤活性显增强,肿瘤局部出现更多的坏死和炎性浸润细胞。结论:采用瘤体直接注射IL-2重组腺病毒对胶质母细胞瘤皮下荷瘤有治疗,其机制可能是增强了宿主的局部和全身抗肿瘤免疫反应。 相似文献