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91.
Simmonds  RE; Ireland  H; Kunz  G; Lane  DA 《Blood》1996,88(11):4195-4204
Protein S is a protein C-dependent and independent inhibitor of the coagulation cascade. Deficiency of protein S is an established risk factor for venous thromboembolism. We have used a strategy of specific amplification of the coding regions and intron/exon boundaries of the active protein S gene (PROS1) and direct single-strand solid phase sequencing, to seek mutations in 35 individuals with phenotypic protein S deficiency. Nineteen point mutations (16 novel) in 19 probands (or relatives of probands) with venous thromboembolism are reported here. Fifteen of the 19 mutations were expected to be causal and included 10 missense mutations (Lys9Glu, Glu26Ala, Gly54Glu, Cys145Tyr, Cys200Ser, Ser283Pro, Gly340Asp, Cys408Ser, Ser460Pro, and Cys625Arg). Three of the 15 mutations resulted in premature stop codons (delete T 635 producing a stop codon at position 126, Lys368stop and Tyr595stop) and two were at intron/exon boundaries (+1 G to A in intron d and +3 A to C in intron j). Of the remaining four mutations, three were within intronic sequence and one was a silent mutation within the coding region and did not alter amino acid composition. In two of the 10 missense mutations, reduced plasma protein S activity compared with antigen level suggested the presence of variant (type II) protein S.  相似文献   
92.
目的:分析载脂蛋白B(apoB)基因EcoRI、XbaI、MspI位点和载脂蛋白AI(apoAI)基因-75bp、+83bp位点多态性与哈萨克族人冠心病的关系.方法:采用聚合酶链式反应-限制性片段长度多态性分析法检测185例哈萨克族冠心病患者和216例哈萨克族非冠心病对照者的这些位点多态性.结果:①TC、TG及apoA...  相似文献   
93.
A group of unique Epstein-Barr virus-containing cell lines was derived from the bone marrow of three patients with X-linked agammaglobulinemia. Efforts to obtain cell lines from the peripheral blood of these patients were uniformly unsuccessful. Immunofluorescence analyses as well as biosynthetic studies with [(35)S]methionine indicated unusual patterns of Ig synthesis in many of these bone marrow derived lines. Seven of the lines were of particular interest in that two produced no Ig of any type; two others showed no Ig by fluorescence but small amounts by [(35)S]methionine labeling; one expressed only cytoplasmic μ chains without any evidence of light chain synthesis, and two produced primarily μ chains with only slight amounts of light chains. One of the lines without membrane or cytoplasmic Ig studied in detail grew like a typical lymphoid line and was carried in intermittent culture over a period of 2 yr without Ig expression. One line grew quite differently and resembled the round cell type described previously, which has been obtained from a variety of sources. The cell line with cytoplasmic μ chains and no light-chain expression had the characteristic properties of pre-B cells. Three normal type Ig-producing cell lines also were obtained from the patients. The accumulated evidence obtained in the present study indicates that these unusual cell lines represent normal precursor cells of the B-cell lineage; these grew out in these cases because of the virtual absence of mature B cells that ordinarily overgrow the culture system. However, the possibility that in certain instances they reflect abnormal Ig synthesis characteristic of the disease has not been ruled out.  相似文献   
94.
目的 应用彩色多普勒超声寻找移植肾急性排异反应较为特异的诊断指标.方法 经移植肾穿刺活检证实的急性排异反应患者42例,经长期随访(1年以上)和临床检查证实的功能稳定期患者115例.对两组移植肾长径、宽径、厚径、实质厚度以及主肾动脉和弓状动脉的阻力指数(RI)进行统计学比较;选取肾体积增大,锥体肿大回声减低、RI<0.7、RI≥0.7及RI≥0.8作为诊断标准,按诊断试验评价原则分别计算灵敏度、特异度、误诊率、漏诊率和符合率;并绘制ROC曲线,确定诊断界值.结果 两组的移植肾长径、宽径、厚径及实质厚度差异有统计学意义(P<0.05);急性排异反应组肾内血流灌注减少,肾动脉舒张期血流速度明显下降,RI明显增高,与移植肾功能稳定期比较差异有统计学意义(P<0.05);各诊断标准对应的灵敏度分别为55.30%,55.20%,42.10%,57.90%和31.60%;特异度分别为71.30%、87.10%、25.70%、74.20%、98.20%.结论 肾体积增大、肾锥体肿大、回声减低、RI升高对诊断移植肾急性排异反应有特异性.  相似文献   
95.
96.
Matsuura E  Kobayashi K  Hurley BL  Lopez LR 《Lupus》2006,15(7):478-483
Oxidized low-density lipoprotein (oxLDL) interacts in vitro with beta2-glycoprotein I (beta2GPI) via LDL-derived specific ligands forming oxLDL/beta2GPI complexes. Circulating oxLDL/beta2GPI complexes have been demonstrated in patients with systemic lupus erythematosus (SLE) and antiphospholipid syndrome (APS). Autoimmune vascular inflammation and oxidative stress contribute to oxLDL/beta2GPI complex formation. Immunohistochemical staining of atherosclerotic lesions suggest that these complexes are formed in the arterial wall and released into circulation. The demonstration of antibodies to oxLDL/beta2GPI complexes indicates that these complexes are immunogenic, and the coexistence of complexes and antibodies suggest an active pro-thrombotic/pro-atherogenic role in the development of autoimmune vascular complications. Circulating oxLDL/beta2GPI complexes can be measured by ELISA using a monoclonal antibody specific to complexed human beta2GPI to capture beta2GPI bound to oxLDL. An enzyme-conjugated monoclonal antibody to human Apo B 100 allows the specific detection of oxLDL/beta2GPI complexes. OxLDL/beta2GPI complexes were common in SLE and APS patients suggesting an underlying process of inflammation and oxidation. Using oxLDL/beta2GPI complexes as capture antigen, antibodies to oxLDL/beta2GPI can be measured by ELISA. Serum levels of IgG anti-oxLDL/beta2GPI antibodies were significantly higher in SLE patients with APS compared to SLE controls without APS. Further, high titers of these IgG antibodies were observed in APS patients with a history of arterial thrombosis. The presence of circulating oxLDL/beta2GPI complexes and IgG antibodies to these complexes indicates significant vascular injury and oxidative stress as well as an active role in autoimmune-mediated atherothrombosis.  相似文献   
97.
We report on the medical management and outcome of a child with classical phenylketonuria (PKU) who developed acute lymphoblastic leukemia (ALL). Chemotherapy began at 24 months of age. Initial problems associated with treatment lead to remarkable releases of phenylalanine, a neurotoxin. Causes included increased catabolism secondary to tumor lysis and chemotherapy, as well as infection, intermittent fasting and anorexia. Medical management involved daily monitoring of Phe levels and major changes in the amount of medical formula and the intake of protein containing foods in the diet. The child is currently in remission from ALL and has a normal neurodevelopmental outcome 7 years after the ALL diagnosis.  相似文献   
98.
To determine the influence of the vitamin D receptor (VDR) gene FokI and BsmI genotype on bone mineral density response to two exercise training modalities, 206 healthy men and women (50-81 years old) were studied before and after approximately 5-6 months of either aerobic exercise training (AT) or strength training (ST). A totla of 123 subjects completed AT (51 men, 72 women) and 83 subjects completed ST (40 men, 43 women). DNA was extracted from blood samples of all subjects and genotyping was performed at the VDR FokI and BsmI locus to determine its association to training response. Total body, greater trochanter and femoral neck bone mineral density (BMD) were measured before and after both training programmes using dual-energy X-ray absorptiometry. VDR BsmI genotype was not significantly related to BMD at baseline or after ST or AT. However, VDR FokI genotype was significantly related to ST- but not AT-induced changes in femoral neck BMD (P < 0.05). The heterozygotes (Ff) in the ST group approached a significantly greater increase in femoral neck BMD (P = 0.058) compared to f homozygotes. There were no significant genotype relationships in the AT group. These data indicate that VDR FokI genotype may influence femoral neck BMD response to ST, but not AT.  相似文献   
99.
Ten novel HLA-DRB1 and one DRB3 alleles are described. Eight of the variants are single-nucleotide substitutions, four resulting in an amino acid change (DRB1*1145, *1148, *0828 and *1514) and four with silent substitutions (DRB1*040504, *130103, *160502 and DRB3*020204). Two alleles differ by two nucleotide changes altering one (DRB1*1447 and *1361) amino acid and one allele alters three nucleotides and two amino acids.  相似文献   
100.
In search for a possible explanation of the phenotypic heterogeneity in IgA deficiency, we studied the function of B cells from IgA-deficient (IgAd) individuals. Two groups of IgAd individuals, one frequently infected and one clinically apparently healthy, as well as normal controls, were studied. Peripheral blood mononuclear cells (PBMC) and B cells from IgAd individuals and controls were cultured with Staphylococcus aureus Cowan I strain and with anti-CD40 MoAb presented on the CD32-transfected fibroblast cell line in the presence of IL-10. In this experimental system PBMC and B cells from the infection-prone IgAd individuals produced only minute amounts of IgA. In contrast, PBMC and B cells from healthy IgAd subjects secreted significantly more IgA1 and IgA2 in comparison with infection-prone IgAd patients (P < 0.05). These data suggest that the abnormalities of B cell differentiation in IgAd could be of heterogeneous origin. Thus, whereas in healthy IgAd subjects IgA production may be efficiently up-regulated in vitro by addition of IL-10 to CD40-activated B cell culture, the corresponding B cell differentiation does not occur in infection-prone IgAd patients. These observations provide a conceptual framework for phenotypic heterogeneity in IgAd subjects.  相似文献   
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