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排序方式: 共有706条查询结果,搜索用时 15 毫秒
41.
Apperloo RC Hoppenreijs TJ Kusters ST Wagemans PA 《Nederlands tijdschrift voor tandheelkunde》2003,110(8):332-334
Two developing supernumerary bicuspids were noticed accidentally in the mandible of a 12 years old girl when evaluating an impacted 35 on a radiograph. The development of these teeth was followed, but at a later stage they were removed. In a 17 years old man multiple complete developed bicuspids were seen on a radiograph. The backgrounds and treatment concerning supernumerary bicuspids in the mandible are discussed. 相似文献
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43.
Aspergillus endocarditis in chronic granulomatous disease 总被引:2,自引:0,他引:2
We report the first case, to our knowledge, of Aspergillus endocarditis in chronic granulomatous disease in a patient who also had an atrial septal defect. A diagnosis was made on culture of the organism from the mass despite extensive prior investigation. The presence of distinctive skin lesions as a diagnostic clue of fungaemia is highlighted. Possible advances in diagnosis by detection of fungal cell wall components and in prophylaxis by use of itraconazole are referred to. We conclude that fungal endocarditis should be considered in this condition, especially in the presence of a structural heart defect. 相似文献
44.
Szelenyi I Hochhaus G Heer S Kusters S Marx D Poppe H Engel J 《Drugs of today (Barcelona, Spain : 1998)》2000,36(5):313-320
There are several approaches for developing new antiallergic/antiasthmatic agents. One of them is the improvement of an existing class of effective drug classes. Due to some undesired effects of intranasal or inhaled corticosteroids, there is a need for better tolerated corticosteroids. Loteprednol etabonate belongs to the so-called class of soft steroids because it is metabolized by a one-step reaction (hydrolysis) without using the cytochrome P450 monooxygenase system. In in vitro investigations using human cells, loteprednol inhibited the release of proinflammatory cytokines (e.g., TNF-alpha, GM-CSF, IL-4, IL-5) according to its relative binding potency to the glucocorticoid receptor. In in vivo animal studies, loteprednol effectively inhibited allergically induced vascular leakage in the nasal cavity of actively sensitized Brown Norway rats and rhinorrhea in actively sensitized domestic pigs following nasal challenge. In several models of allergic asthma, it was clearly demonstrated that loteprednol was able to suppress the allergically induced late phase eosinophilia in mice, rats and guinea pigs. After intrapulmonary administration of loteprednol, only a slight, statistically nonsignificant reduction in thymus weight was observed in a dose range far less than the therapeutically relevant doses. Its therapeutic ratio is clearly superior to those of beclomethasone and budesonide. Loteprednol is a safe steroid with an extremely wide range between therapeutic and side effect inducing doses. Its elimination profile, its pronounced binding to plasma protein and erythrocytes and the low oral bioavailability makes this drug highly suitable for nasal or pulmonary use. 相似文献
45.
Bijlsma JJ Vandenbroucke-Grauls CM Phadnis SH Kusters JG 《Infection and immunity》1999,67(5):2433-2440
The complete genome of the gram-negative bacterial pathogen Helicobacter pylori, an important etiological agent of gastroduodenal disease in humans, has recently been published. This sequence revealed that the putative products of roughly one-third of the open reading frames (ORFs) have no significant homology to any known proteins. To be able to analyze the functions of all ORFs, we constructed an integration plasmid for H. pylori and used it to generate a random mutant library in this organism. This integration plasmid, designated pBCalpha3, integrated randomly into the chromosome of H. pylori. To test the capacity of this library to identify virulence genes, subsets of this library were screened for urease-negative mutants and for nonmotile mutants. Three urease-negative mutants in a subset of 1,251 mutants (0.25%) and 5 nonmotile mutants in a subset of 180 mutants (2.7%) were identified. Analysis of the disrupted ORFs in the urease-negative mutants revealed that two had disruptions of genes of the urease locus, ureB and ureI, and the third had a disruption of a unrelated gene; a homologue of deaD, which encodes an RNA helicase. Analysis of the disrupted ORFs in the nonmotile mutants revealed one ORF encoding a homologue of the paralyzed flagellar protein, previously shown to be involved in motility in Campylobacter jejuni. The other four ORFs have not been implicated in motility before. Based on these data, we concluded that we have generated a random insertion library in H. pylori that allows for the functional identification of genes in H. pylori. 相似文献
46.
47.
Human myeloid alpha 3-fucosyltransferase is involved in the expression of the sialyl-Lewis(x) determinant, a ligand for E- and P-selectin 总被引:1,自引:0,他引:1
Easton EW; Schiphorst WE; van Drunen E; van der Schoot CE; van den Eijnden DH 《Blood》1993,81(11):2978-2986
The sialyl-Lex determinant (NeuAc alpha 2-->3Gal beta 1-->4[Fuc alpha- 1-->3]GlcNAc) has been identified as a major ligand in the selectin- mediated adhesion of neutrophils and monocytes to activated endothelium or platelets. This carbohydrate epitope is formed by the sequential action of alpha 3-sialyltransferase and alpha 3-fucosyltransferase on N- acetyllactosamine (Gal beta 1-->4GlcNAc) disaccharide termini of glycoconjugates. We have addressed the role of the human myeloid alpha 3-fucosyltransferase in the expression of this epitope at the leucocyte surface by determining its activity in human-mouse leukemic cell hybrids (WEGLI), normal human granulocytes and chronic myeloid leukemia (CML) cells using sialylated and desialylated glycoproteins and oligosaccharides as acceptor substrates. In contrast to what has been reported for the myeloid-type enzyme, we found that the alpha 3- fucosyltransferase of the cells studied can use sialylated acceptors be it that the activity is several times lower than with asialo- substrates. Characterization of the product obtained with a sialylated oligosaccharide indicated that the enzyme can catalyze the formation of the sialyl-Le(x) structure. Flow cytometry of the WEGLI cells using a sialyl-Le(x)-specific monoclonal antibody (MoAb) showed that these cells indeed express sialyl-Lex at their surface, provided that they contain human chromosome 11. Earlier the presence of this chromosome had been correlated with the expression of alpha 3-fucosyltransferase activity. In addition to sialyl-Le(x), WEGLI cells containing chromosome 11 showed high-expression levels of related structures recognized by antibodies VIM-2 and VIM-8, suggesting that fucose addition can occur at both distal and proximal GlcNAc residues in poly- N-acetyl-lactosaminoglycan sequences. Based on the human chromosome contents it could be ruled out that the alpha 3-fucosyltransferase of WEGLI cells is a Lewis-type alpha 3/4- or plasma-type alpha 3- fucosyltransferase, the genes of which have been mapped to chromosome 19. It is concluded that the enzyme studied is of the myeloid-type and indeed is involved in the synthesis of sialyl-Le(x) (and also VIM-2 and VIM-8 structures) in leukocytes provided that its expression is at a sufficiently high level. 相似文献
48.
49.
G. Müller K. Norpoth E. Kusters K. Herweg E. Versin 《International archives of occupational and environmental health》1978,41(3):199-205
Summary A strong correlation was found between vinyl chloride concentrations at working places and the increased excretion of thiodiglycolic acid of 18 exposed workers. The mean air concentration of vinyl chloride was calculated referring to personal exposure. The values obtained were in the range of 0,14–7,0 ppm. The excretion of thiodiglycolic acid — measured by GC-MS analysis — amounted to 0,3 – 4,0 mg/L. It could be demonstrated that significant increases of the metabolite excretion occur even at VC-concentrations below 5 ppm. 相似文献
50.
Sprengers D van der Molen RG Kusters JG Kwekkeboom J van der Laan LJ Niesters HG Kuipers EJ De Man RA Schalm SW Janssen HL 《Journal of viral hepatitis》2005,12(5):507-512
SUMMARY: Information about the character and grade of the intrahepatic immune response in viral hepatitis is important for the evaluation of disease stage and effect of therapy. Complications like haemorrhage limit the frequent performance of tissue-needle biopsies (TB), and the cells of peripheral blood have to be used as surrogate markers instead. Fine-needle-aspiration biopsy (FNAB) of the liver represents a safe and atraumatic method that allows frequent cytological sampling. Our aim was to investigate whether flow cytometry of FNAB specimens allows co-analysis of phenotype, function and specificity of key populations of liver-infiltrating lymphocytes (LIL). In 20 consecutive patients with chronic viral hepatitis [10 hepatitis B virus (HBV), 10 hepatitis C virus (HCV)], flow cytometry was performed on FNAB cytology, and simultaneously on lymphocytes isolated from a TB and peripheral blood mononuclear cells (PBMC). The ratio of CD8+/CD4+ lymphocytes in FNAB correlated well with LIL from TB (r =0.78, P < 0.05) but differed from PBMC (mean ratio: 2.6, 2.1 and 0.7, respectively). Similarly, a correlation was observed for percentage CD56+ natural killer (NK) cells (mean %: 29.9, 32.3 and 14.5, respectively; r = 0.69, P < 0.05). The percentage of interferon (IFN)-gamma-producing CD3+ lymphocytes in both FNAB and TB was higher than in PBMC (mean %: 41, 44 and 22, respectively; P < 0.05). Furthermore, tetrameric complexes allowed analysis of HBV-specific T cells in FNAB specimens. In conclusion, flow cytometry of FNAB allows easy, atraumatic and reliable analysis of lymphocytes obtained from the intrahepatic compartment. Therefore, the FNAB is a valuable tool in the study of the immunopathology of viral hepatitis, and it may contribute to the improved clinical evaluation of chronic viral liver disease. 相似文献