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71.
Smeitink JA van den Heuvel LW Koopman WJ Nijtmans LG Ugalde C Willems PH 《Current neurovascular research》2004,1(1):29-40
Human complex I (NADH:ubiquinone oxidoreductase; EC 1.6.5.3) is the first and largest multi-protein assembly of the mitochondrial oxidative phosphorylation (OXPHOS) system; the final biochemical cascade of events leading to the production of ATP. The complex consists of 46 subunits, 7 encoded by the mitochondrial DNA and the remainder by the nuclear genome. In recent years, numerous gene mutations leading to an isolated complex I deficiency have been characterized in both genomes. Disorders associated with complex I deficiency (OMIM 252010) mostly lead to multi-system disorders affecting brain, skeletal muscle and the heart. Of these, Leigh syndrome, a progressive fatal encephalopathy symmetrically affecting specific areas of the brain, brainstem and myelin, is the most frequently observed phenotype. Here, we review the current understanding of the cell biological consequences of isolated complex I deficiencies and propose further directions the field needs to take in order to develop rational treatment strategies for these devastating disorders. 相似文献
72.
Detection of human papillomavirus DNA in pterygia from different geographical regions 总被引:3,自引:0,他引:3
Piras F Moore PS Ugalde J Perra MT Scarpa A Sirigu P 《The British journal of ophthalmology》2003,87(7):864-866
BACKGROUND/AIMS: The aetiology and pathogenesis of pterygia remain unclear and the involvement of human papillomavirus (HPV) is controversial. 41 pterygia from two geographic locations were evaluated for the presence of HPV DNA. METHODS: 41 pterygium biopsies (17 from Italy and 24 from Ecuador) were analysed using the L1C1 and PU-1ML primer sets by polymerase chain reaction (PCR) and DNA sequence analysis. RESULTS: 22 of the 41 pterygia (54%) were positive for HPV, including all 17 Italian cases and 5/24 (21%) Ecuadorean cases. DNA sequencing of the 22 positive cases showed that 11 were HPV type 52, four were type 54, five were candHPV90, and two of unknown genotype. CONCLUSIONS: The major differences in the frequency of HPV in geographically distant populations might suggest a possible explanation for the vast differences in the reported detection rates. Three subtypes of HPV were found in this sample of pterygia. None the less, these results suggest that HPV may have a pathogenic role in pterygium. 相似文献
73.
AM Pierides HA Ellis H Dellagrammatikas JE Scott AW Norman 《Archives of disease in childhood》1977,52(6):464-472
Three children with azotaemic renal osteodystrophy were treated with 1,25-dihydroxycholecalciferol (1,25(OH)2D3). All showed clinical, biochemical, and radiological improvement within 6 months of starting treatment. There were no complications. The dose of 1,25(OH)2D3 required was 0-5 microgram per day for 2 children aged 22 and 30 months, and 2 microgram per day for a 15-year-old boy. 2 of the patients were receiving phenobarbitone and phenytoin and in one of them prior treatment with dihydrotachysterol 0-5 mg daily and 6 microgram 1alpha-hydroxycholecalciferol (1alphaOHD3) daily had failed to induce improvement. In one patient, in whom serial iliac bone samples were available, 2 microgram 1,25(OH)2D3 resulted in histological improvement in previously severe osteomalacia. 1,25(OH)2D3 appears to be an effective and safe drug in the treatment of uraemic osteodystrophy. 相似文献
74.
Secretion of proteins in Gram-negative bacteria is a high-energy-consuming process that requires translocation across two membranes and a periplasmic space composed of a mesh-like layer, the peptidoglycan. To achieve this, bacteria have evolved complex secretion systems that cross these barriers, and in many cases there are specific peptidoglycanases that degrade the peptidoglycan to allow the proper assembly of the secretion machinery. We describe here the identification and characterization of a muramidase in Brucella abortus that participates in the intracellular multiplication in professional and nonprofessional phagocytes. We demonstrated that this protein has peptidoglycanase activity, that a strain with a clean deletion of the gene displayed a defect in the early stages of the intracellular multiplication curve, and that this is dependent on the lytic activity. While neither the attachment nor the invasion of the strain was affected, we demonstrated that it had a defect in excluding the lysosomal marker LAMP-1 but not in acquiring the reticulum endoplasmic marker calnexin, indicating that the gene participates in the early stages of the intracellular trafficking but not in the establishment of the replicative niche. Analysis of the assembly status and functionality of the VirB secretion apparatus indicated that the mutant has affected the proper function of this central virulence factor. 相似文献
75.
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77.
A Nørremølle E Budtz-Jørgensen K Fenger JE Nielsen SA Sørensen and L Hasholt 《Clinical genetics》2009,75(3):244-250
Huntington disease (HD) is caused by an expanded CAG repeat sequence in the HD gene. Although the age at onset is correlated to the CAG repeat length, this correlation only explains approximately half of the variation in onset age. Less variation between siblings indicates that the variation is, in part, explained by genetic modifiers. We analyzed polymorphic loci within or close to the HD gene on the HD chromosome in Danish HD patients. We found one specific haplotype segregating with later age at onset, compared with patients with similar CAG repeat length and another haplotype. The nine Danish families in the study carrying this haplotype most likely have a common founder. Several of the polymorphic loci displayed alleles that may be specific to the late-onset haplotype, implicating that from this study we cannot determine which of the loci tested (or other polymorphic loci in this chromosomal area) do in fact contain genetic modifiers of age at onset. 相似文献
78.
79.
JE Barberie DG Connell PL Munk DL Janzen 《Journal of Medical Imaging and Radiation Oncology》1999,43(3):355-357
Muscle and nerve injuries in the hand may be difficult to detect and diagnose clinically. Two cases are reported in which magnetic resonance imaging showed ulnar nerve injury and intrinsic hand muscle denervation. The clinical, anatomical and radiological features of injury to the deep motor branch of the ulnar nerve and associated muscle denervation are discussed and illustrated. 相似文献
80.