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11.
A number of HLA alleles have been newly identified. This concerns HLA-A*0310, A*2907, B*4435, Cw*0206, Cw*0506, of which Cw*0206 was found in three unrelated individuals, all B*4002 positive. Some other alleles are also presented but confirm earlier detected sequences: A*3106, Cw*0314, DRB1*0322, and DRB1*1433. Moreover, we identified B*3924 in a bone marrow transplant recipient and in five of six unrelated stem cell donors, selected for this patient. In all cases, B*3924 was found on a haplotype combining A*0201, B*3924, Cw*0701, and DRB1*1303. The observation of this extended haplotype is of importance for the selection for stem cell transplantation. Cells expressing B*3924 and B*4435 were typed by serology as B39 and B44, respectively. Cells expressing HLA-A*0310 do not express A3 but type as A-Blank.  相似文献   
12.
The MART-1/Melan-A melanoma antigen recognized by the majorityof HLA-A2-restricted tumorinfiltrating lymphocytes is a selfantigen expressed on melanocytes and the retina. We have investigatedwhether Vogt–Koyanagi–Harada (VKH) disease and sympatheticophthalmia (SO), systemic inflammatory disorders affecting variousorgans containing melanocytes, are autoimmune diseases directedtoward the MART-1 antigen. In two of three patients with VKHdisease and one patient with SO, CD8+ T cell clones (TCC) fromintraocular fluid of HLA-A2+ patients lysed T2 cells when pulsedwith a HLA-A2-binding MART-1 peptide, but not a HLA-A2-bindingpMel-17 or tyrosinase peptide, in a HLA-A2-restricted manner.These CD8+ TCC lysed both melanocytes and melanoma cells ina HLA-A2-restricted manner. In addition, CD8+ TCC recognizinga HLA-A2-binding MART-1 peptide were also established from peripheralblood mononuclear cells of a patient with VKH disease. In contrast,either CD4+ TCC from these patients or CD8+ TCC from the intraocularfluid of HLA-A2+ patients with uveitis associated with Behcet'sdisease or HTLV-I uveitis did not show this cytotoxicity. Theresults demonstrate that the MART-1 peptide-specific cytotoxicT lymphocytes lyse melanocytes in the eye of patients with VKHdisease or SO, suggesting that these diseases are autoimmunediseases directed toward the MART-1 antigen in HLA-A2+ patients.  相似文献   
13.
With the use of polymerase chain reaction (PCR) and sequence-specific oligonucleotide probe (SSOP), we established a DNA typing method of the HLA - A locus. A pair of primers to amplify the highly polymorphic region of HLA-A gene including exon 2 and exon 3 was designed and the amplified DNAs were hybridized with 91 types of 32P labeled SSOPs. This method allowed discrimination of all known HLA-A alleles except for two combinations, A*0201 or A*0209 and A*0207 or A*0215N, which have identical sequences in exon 2 and exon 3. Another pair of primers was designed for amplification of exon 4 and the PCR products were hybridized with 5 SSOPs to distinguish A*0201 and A*0207 from A*0209 and A*0215N, respectively. In this study, 81 B-lymphoblastoid cell lines (BLCL) homozygous for HLA and 553 unrelated healthy Japanese individuals were determined for their HLA-A genotypes. Based on the genotyping results, frequency of HLA-A alleles and linkage disequilibrium between HLA-A and HLA-B in the Japanese population were investigated. In addition, four new HLA-A alleles were identified and their nucleotide sequences in exon 2 and exon 3 were determined to confirm the typing results.  相似文献   
14.
目的:优化诱导条件大批量表达生物素化酶BirA底物肽(BSP)与HLA-A*0203重链胞外域的融合蛋白(HLA—A*0203、BSP),并制备负载HLA-A*0203限制性EB病毒抗原肽EBNA3 596-604的四聚体(HIA—A}0203/SVR)。方法:以HLA—A*0203-BSP原核表达载体转化E.coli BL21(DE3)菌株,优化诱导条件进行大批量重组蛋白的表达。通过稀释法复性可溶性HLA-A*0203/SVR单体,然后以BirA对其进行生物素化,并以阴离子交换树脂纯化。将纯化的HLA-A*0203/SVR单体与荧光素标记的链亲和素按4:1的比例混合形成四聚体,通过对特异性CTL进行染色验证其结合活性。结果:当IPTG的浓度为0.4mmol/L,于37℃诱导过夜后,融合蛋白的表达最多。该重组蛋白相对分子质量(Mr)为34003,与HLA—A*0203-BSP的理论Mr相一致。该重组蛋白以包涵体形式存在于沉淀部分,约占菌体总蛋白的30%。负载抗原肽的可溶性HLA-A*0203/SVR单体是在同时存在HLA-A*0203,BSP、β2微球蛋白及HLA-A*0203限制性抗原肽SVR的情况下通过稀释法复性而获得。该单体生物素化并纯化后与荧光素标记的链亲和素按4:1的比例混合后即形成四聚体。流式细胞术(FCM)分析证实,该四聚体具有与HLA—A2^+供者特异性CTL结合的活性。结论:HLA—A*0203-BSP融合蛋白在优化条件下获得高效表达。以此蛋白制备的HLA-A*0203/SVR四聚体具有与HLA-A2^+供者特异性CTL结合的活性,为研究HLA—A*0203个体EB病毒特异性CTL的免疫应答打下了基础。  相似文献   
15.
目的 序列分析及确认一例中国人群中的人类白细胞抗原(human leukocyte antigen,HLA)新等位基因.方法 应用基于Luminex平台的聚合酶链反应-序列特异性寡核苷酸探针(PCR-SSOP)基因分型法、PCR产物测序法和组特异性引物测序法,通过软件分析该样本DNA基因序列及与最相近HLA等位基因序列的差异.结果 PCR-SSOP结果显示该样本HLA-A基因座的反应格局与已知HLA-A等位基因均不一致;DNA序列分析显示,在所检测的第2~4外显子中,该样本HLA-A基因座序列与所有已知HLA-A等位基因序列均不一致,与同源性最高的等位基因A*31∶01∶02的差异只在外显子2区域中产生了nt 245 A—C一个碱基取代,并导致相应的82位密码子由GAG→GCG,编码的氨基酸由谷氨酸(Glu)变为丙氨酸(Ala).结论 该基因为HLA新等位基因,被世界卫生组织HLA因子命名委员会正式命名为HLA-A*31∶22.  相似文献   
16.
We describe a novel HLA-A*02 allele, A*0224, that was identified after a comparison of DNA and serological typing revealed a discrepancy in the HLA-A types: HLA-A2 was defined by serology but was not detected by the polymerase chain reaction using sequence-specific primers (PCR-SSP). DNA sequencing indicated the presence of a variant HLA-A*02 allele that differed from A*0201 by a single base (C/A) at position 453. This base substitution corresponded to the annealing site of a primer common to the two A*02-amplifying PCR-SSP mixtures used in the method. This provides an explanation for the results and highlights a limitation of PCR-SSP methods even where two PCR mixtures are used to detect alleles. Serological titration studies suggested that A*0201, A*0205 and A*0224 are unlikely to be differentiated during routine serological typing.  相似文献   
17.
High-resolution polymerase chain reaction using sequence-specific oligonucleotide probes (PCR-SSOP) typing methods for HLA-A identification have been established. The four systems, which operate independently of each other, are intended for use as secondary typing systems following HLA-A identification with a medium-resolution PCR-SSOP technique. The systems, all using digoxigenin-labelled probes, are based on group specific amplifications for resolution of: i) HLA-A*29 & -A*33; ii) HLA-A*24 & -A*30; and iii) HLA-A*26, -A*25, -A*11, -A*34, -A*66 and -A*68 alleles, respectively. The fourth system, for the detection of HLA-A*02 alleles, is a modification of a previously reported PCR-SSOP subtyping system. The methods have been applied to individuals from the local bone marrow registry and HLA-A allele frequencies for the Northern Ireland population have been established.  相似文献   
18.
目的探讨应用siRNA技术下调HLA-A2表达的人骨髓间充质干细胞(human mesenchymal stemcells,hMSCs)对人异体T淋巴细胞分泌功能的调节作用。方法从成人骨髓中分离和培养hMSCs,并且通过免疫细胞化学检测其表面标志;利用人工合成HLA-A2靶向小分子干扰RNA转染至第3代hMSCs,然后将转染前后的hMSCs,与经植物血凝素(PHA)刺激的人异体T淋巴细胞共同培养。用ELISA分别检测各培养上清液中T淋巴细胞分泌IFN-γ和IL-2的水平。结果原代培养3d后,约70%hMSCs贴壁生长,7d后细胞迅速增殖,进入对数生长期,14d左右进入平台期,第3代细胞多呈梭形生长,形态比较均一,hMSCs表面抗原CD44、CD166阳性。HLA-A2靶向小分子干扰RNA转染3天后,可见少量细胞死亡,免疫荧光染色可见细胞核和部分胞浆呈阳性表达。转染HLA-A2靶向小分子干扰RNA的和未转染的hMSCs均能抑制人T淋巴细胞分泌IFN-γ和IL-2,转染后的hMSCs抑制作用强于未转染的hMSCs(<0.05)。结论体外沉默HLA-A2基因表达可增强hMSCs抑制PHA刺激人T淋巴细胞分泌因子。  相似文献   
19.
HLA-A*02 allele frequencies and haplotypic associations in Koreans   总被引:1,自引:0,他引:1  
Park MH  Whang DH  Kang SJ  Han KS 《Tissue antigens》2000,55(3):250-256
We have investigated the frequencies of HLA-A*02 alleles and their haplotypic associations with HLA-B and -DRB1 loci in 439 healthy unrelated Koreans, including 214 parents from 107 families. All of the 227 samples (51.7%) typed as A2 by serology were analyzed for A*02 alleles using polymerase chain reaction (PCR)-low ionic strength-single-strand conformation polymorphism (LIS-SSCP) method. A total of six different A*02 alleles were detected (A*02 allele frequency 29.6%): A*0201/9 (16.6%), *0203 (0.5%), *0206 (9.3%), *0207 (3.0%), and one each case of *0210 and *02 undetermined type. Two characteristic haplotypes showing the strongest linkage disequilibrium were A*0203-B38-DRB]*1502 and A*0207-B46-DRB1*0803. Besides these strong associations, significant two-locus associations (P<0.001) were observed for A*0201 with B61, DRB1*0901 and DRB1*1401, and for A*0206 with B48 and B61. HLA haplotypes carrying HLA-A2 showed a variable distribution of A*02 alleles, and all of the eight most common A2-B-DR haplotypes occurring at frequencies of > or =1% were variably associated with two different A*02 alleles. These results demonstrate that substantial heterogeneity is present in the distribution of HLA-A*02 alleles and related haplotypes in Koreans.  相似文献   
20.
Identification of human leukocyte antigen (HLA) antigens that are known as the highest polymorphic genes has become a valuable tool for tissue transplantation, platelet transfusion, disease susceptibility or resistance, and forensic and anthropological studies. In the present study, the allele and haplotype frequencies of HLA-A, HLA-B, and HLA-DRB1 were studied in 237 unrelated healthy Western Javanese (Indonesia) by the high-resolution polymerase chain reaction-Luminex method. A total of 18 A, 40 B, and 20 DRB1 alleles were identified. The most frequent HLA-A, -B, and -DRB1 alleles were HLA-A*2407 (21.6%), HLA-B*1502 (11.6%) and HLA-B*1513 (11.2%), and DRB1*1202 (37.8%), respectively. The most frequent two-locus haplotypes were HLA-A*2407-B*3505 (7%) and HLA-B*1513-DRB1*1202 (9.2%), and three-locus haplotypes were HLA-A*3401-B*1521-DRB1*150201 (4.6%), HLA-A*2407-B*3505-DRB1*1202 (4.3%), and HLA-A*330301-B*440302-DRB1*070101 (4.2%). HLA allele and haplotype frequencies in addition to phylogenetic tree and principal component analyses based on the four-digit sequence-level allele frequencies for HLA-A, HLA-B, and HLA-DRB1 showed that Western Javanese (Indonesia) was closest to Southeast Asian populations.  相似文献   
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