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排序方式: 共有6905条查询结果,搜索用时 492 毫秒
61.
N. Casamitjana J. Gil E. Campos M. Santos N. Nogués A. Ribera E. Palou 《Tissue antigens》2001,58(4):269-271
We report here the identification of a novel DQB1*06 allele, DQB1*0618, found in a bone marrow donor. The new allele was detected during routine DNA-based HLA typing by an ambiguous pattern of probe hybridization, obtained by polymerase chain reaction using sequence-specific oligonucleotides (PCR-SSO). Molecular cloning and sequencing confirmed that the new allele is identical to DQB1*0609 at exon 2 except for 3 nucleotide substitutions at positions 353, 356 and 367, also found in other alleles. These nucleotide changes may explain its anomalous reactivity. 相似文献
62.
H1N2新亚型流感病毒神经氨酸酶基因来源的进一步研究 总被引:1,自引:0,他引:1
对流感病毒H1N2亚型重组株A/哈防/1/88、A/哈防/12/92以及H3N2亚型病毒株A/雅防/2/87、A/京防/57/898和A/粤防/1/92神经氨酸酶(NA)基因核苷酸全序列的测定,进一步弄清了A/哈防/1/88病毒株的NA基因确来自当时人群中流行的H3N2亚型病毒株,很可能是来自A/雅防/2/87类病毒株;而A/哈防/12/92病毒株的NA基因可能是与A/哈防/1/88病毒株的NA基 相似文献
63.
Alleles encoding HLA-C antigens in Japanese were identified by polymerase chain reaction followed by single strand conformation polymorphism (PCR-SSCP) and nucleotide sequencing analyses. The results showed that at least sixteen different alleles code for eight serologically detectable antigen groups and undetectable blanks. Cwl was mainly encoded by Cw*0102, whereas two split antigens of Cw3, Cw9 and Cw10, were encoded by Cw*0303 and Cw*0304, respectively. Cw4 and Cw6 were encoded by Cw*0401 and Cw*0602, respectively. Seven alleles, Cw*0801, Cw*0803, Cw*1202, Cw*1203, Cw*1402, Cw*1403 and Cw*1502, were found to encode serological HLA-C "blanks" in Japanese. Moreover, errors in the published nucleotide sequences of Cw*0501 and Cw*1201 were corrected. Twenty-one HLA-C alleles were distinguished from each other by means of group-specific PCR amplification followed by the SSCP method developed in the present study. The system using genomic DNAs can be used effectively for identification of new HLA-C alleles. 相似文献
64.
M. Laforet N. Froelich A. Parissiadis B. Pfeiffer A. Schell B. Faller M.-L. Woehl-Jaegle J.-P. Cazenave M.-M. Tongio 《Tissue antigens》1997,50(4):347-350
HLA class I typing performed in parallel by molecular biology and serology has revealed cases where an HLA class I allele was identified whereas the corresponding antigen was not detected on the cell surface. In the present report, we describe four members of a family in whom an HLA-A 1 allele identified at the molecular level was typed as A "blank" by lymphocytotoxicity. This serologically blank antigen was undetectable by isoelectric focusing (IEF). Sequencing of the HLA-A*01 allele from the promoter region to the eighth exonic region revealed insertion of a "C" nucleotide at the beginning of the fourth exon as compared to the common HLA-A*0101 allele. This mutation causes a frame shift, giving rise to an early stop codon in the fourth exon. 相似文献
65.
目的 从烧伤合并内毒素血症致多器官损害家兔血清中分离纯化内毒素结合蛋白 ,并初步对比研究它们的生物学活性。方法 兔血清蛋白质通过二步离子交换层析 (Bio Rex 70Resin、Mono Q)及凝胶过滤分离纯化 ,并经流式细胞分析实验、绵羊红细胞凝聚实验、氨基末端氨基酸残基测序等方法鉴定 ,再将所获蛋白质作用于体外培养的人单核细胞 (U937) ,观测其分泌TNFα等细胞因子的生物效应。结果 获得两种具有促进内毒素 (LPS)与外周血单核细胞 (PBMC)结合的蛋白质 ,其中一种相对分子质量为 6 0× 10 4 ,其N端 10个氨基酸序列为TNPGLITRIT ,证实为兔内毒素结合蛋白 (LBP) ;另一种蛋白质相对分子质量为 4 8× 10 4 ,其N端 10个氨基酸序列为GSQGTFTSEE ,与NCBI蛋白质库中的氨基酸序列进行比较 ,未发现相同序列 ,命名为p48。结论 p48与LBP具有相似的生物学功能 ,p48的生物学活性稍弱于LBP。提示体内除LBP外 ,p48也同样起着介导LPS的毒性作用。这可能是近年国外研究中阻断LBP的活性后 ,机体毒性反应并无明显减轻的原因之一。 相似文献
66.
Dunckley H Dodd R Greville WD Hersee J Le T Taverniti A Wallace R Strickland J Hogbin JP Truong J Velickovic ZM 《Tissue antigens》2004,63(6):584-586
Anew human leukocyte antigen-B allele, B*1565, has been identified during routine typing of cord blood samples. Subsequently, two individuals from the same family as the first cord blood sample plus two unrelated Australian Bone Marrow Donor Registry samples have been found to carry this novel allele. 相似文献
67.
目的从基因水平调查了中国华南、华北地区人群HLA-DQB1等位基因频率,并研究比较两地区人群HLA-DQB1多态性分布。方法采用深圳益生堂生物企业有限公司研制开发的“HLA-DQB1低分辨率分型基因芯片检测试剂盒”,应用聚合酶链反应.序列特异性引物+序列特异性寡核苷酸探针芯片检测技术,对700名南方地区的中国人和320名北方地区的中国人进行基因分型。结果鉴定了10个HLA-DQB1等位基因,获得了一组准确、科学的统计数据。结论得到了中国华南、华北地区人群HLA-DQB1等位基因频率差异的数据,证明中国人群HLA-DQB1*02,05,0601,0602,0603的分布南北差异有统计学意义(P〈0.05),为疾病相关性研究、人文科学研究提供了可靠的遗传学数据。 相似文献
68.
We have established a practical method of complete high-resolution typing for all HLA-A alleles using the polymerase chain reaction (PCR)-restriction fragment-length polymorphism (RFLP) technique combined with allele group- and sequence-specific amplification. The second and third exons of the HLA-A gene, in which most allelic variations are observed, were separately amplified by PCRs with 3 and 4 group-specific primer pairs, respectively. Each PCR-amplified product was digested by allele-specific restriction endonucleases and then subjected to electrophoresis on a 10% polyacrylamide gel. In this way, 62 out of 79 HLA-A alleles could be discriminated by the RFLP patterns derived from the genetic polymorphism in the exon 2 and 3 domains. The remaining 17 alleles could be defined unequivocally by either PCR-RFLP analysis after exon 4 amplification or PCR analysis with sequence-specific primers (SSP). By this method, complete HLA-A genotyping for all homozygous and heterozygous combinations can be accomplished, establishing technically simple, economical and practical routine typing of the HLA-A gene, especially for small samples. 相似文献
69.
A racial difference in apolipoprotein E allele frequencies between the Japanese and Caucasian populations 总被引:2,自引:0,他引:2
We have examined the apo E phenotype frequencies in the Japanese population (n = 576, 16-78 years of age). Apo E phenotypes were determined by the rapid flat gel isoelectric focusing method that we previously reported. The apo E phenotype frequencies in the Japanese were 0.3% for E2/2, 6.1% for E3/2, 71.9% for E3/3, 0.7% for E4/2, 19.3% for E4/3 and 1.7% for E4/4. The apo E allele frequencies were 0.037, 0.846 and 0.117 for the epsilon 2, epsilon 3 and epsilon 4 alleles, respectively. These frequencies were compared with those in the Caucasian populations (n = 3033) reported by Sing & Davignon (1985). There was a significant difference in the apo E phenotype frequencies between the Japanese and Caucasian populations. In addition, a significantly lower frequency of the epsilon 2 and epsilon 4 alleles and a significantly higher frequency of the epsilon 3 allele were found in the Japanese than those reported for the Caucasian populations. It is concluded that there is a racial difference in the apo E allele frequencies between the Japanese and Caucasian populations. 相似文献
70.
冠心病家族史青少年载脂蛋白E、B的基因多态性 总被引:8,自引:2,他引:8
目的 探讨青少年载脂蛋白E(apolipoprotein E,apoE)、apoB基因多态性对冠心病的遗传易感性。方法 应用聚合酶链反应—限制性片段长度多态性技术,对244名健康汉族大学生(冠心病家族史阳性者109人,阴性者135人)的apoE、apoB XbaI、apoB 3’可变数目串联重复序列(variable number of tandem repeat ,VNTR)基因型进行分析。结果 阳性组的e4、x^ 、VNTR—B(hypervariable element,HVE>38)等位基因频率显著高于阴性组(P<0.05),且与血总胆固醇、低密度脂蛋白—胆固醇、aPoBl00水平升高有显著相关(P<0.05)。结论 apoE的e4、apoB Xba I的x^ 、apoB3’VNTR的VNTR—B可能为冠心病的重要遗传标记。 相似文献