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Scalabrini D Galimberti D Fenoglio C Comi C De Riz M Venturelli E Castelli L Piccio L Ronzoni M Lovati C Mariani C Monaco F Bresolin N Scarpini E 《Neuroscience letters》2005,388(3):149-152
P-selectin glycoprotein ligand-1 (PSGL-1) is an important adhesion molecule involved in lymphocyte recruitment into the brain, which represents a crucial step in the pathogenesis of multiple sclerosis (MS). Three hundred twenty-one MS patients and 342 controls were genotyped for the presence of a polymorphism in the PSGL-1 gene, consisting of a variable number of tandem repeats (VNTR) originating three possible alleles: A, B and C, in order to test whether they influence the susceptibility and the course of the disease. No significant differences among allelic frequencies of A, B and C alleles in MS as compared with controls were observed. Stratifying patients according to the course of the disease, a significantly increased frequency of the shortest C allele in PP-MS was found (7.1%), either in comparison with controls (P=0.011) or with all other MS patients, who had acute inflammatory attacks at onset and an initial RR form (P=0.036). Besides, none of SP-MS patients was a carrier of the C allele and B carriers converted later from RR to SP course as compared with A/A subjects (after 15.8 rather than 8.8 years, P=0.01). In conclusion, the C allele of the VNTR polymorphism in PSGL-1 is likely to be associated with PP-MS. As this allele has been demonstrated to have a very low efficiency in mediating lymphocyte binding to brain endothelium during attacks, its high frequency in PP-MS could be related to the absence of exacerbations in such patients. 相似文献
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Mauro Podda Nicola Cillara Salomone Di Saverio Antonio Lai Francesco Feroci Gianluigi Luridiana Ferdinando Agresta Nereo Vettoretto 《The surgeon》2017,15(5):303-314
Background
Acute appendicitis is the most common surgical diagnosis in young patients, with lifetime prevalence of about 7%. Debate remains on whether uncomplicated AA should be operated or not. Aim of this meta-analysis of randomized controlled trials was to assess current evidence on antibiotic treatment for uncomplicated AA compared to standard surgical treatment.Methods
Systematic literature search was performed using PubMed, EMBASE, Medline, Google Scholar and Cochrane Central Register of Controlled Trials databases for randomized controlled trials comparing antibiotic therapy (AT) and surgical therapy-appendectomy (ST) for uncomplicated AA. Trials were reviewed for primary outcome measures: treatment efficacy based on 1 year follow-up, recurrence at 1 year follow-up, complicated appendicitis with peritonitis identified at the time of surgical operation and post-intervention complications. Secondary outcomes were length of hospital stay and period of sick leave.Results
Five RCTs comparing AT and ST qualified for inclusion in meta-analysis, with 1.351 patients included: 632 in AT group and 719 in ST group. Higher rate of treatment efficacy based on 1 year follow-up was found in ST group (98.3% vs 75.9%, P < 0.0001), recurrence at 1 year was reported in 22.5% of patients treated with antibiotics. Rate of complicated appendicitis with peritonitis identified at time of surgical operation was higher in AT group (19.9% vs 8.5%, P = 0.02). No statistically significant differences were found when comparing AT and ST groups for the outcomes of overall post-intervention complications (4.3% vs 10.9%, P = 0.32), post-intervention complications based on the number of patients who underwent appendectomy (15.8% vs 10.9%, P = 0.35), length of hospital stay (3.24 ± 0.40 vs 2.88 ± 0.39, P = 0.13) and period of sick leave (8.91 ± 1.28 vs 10.27 ± 0.24, P = 0.06).Conclusions
With significantly higher efficacy and low complication rates, appendectomy remains the most effective treatment for patients with uncomplicated AA. The subgroups of patients with uncomplicated AA where antibiotics can be more effective, should be accurately identified. 相似文献88.
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Platelet endothelial cell adhesion molecule-1 (PECAM-1) is a cell-cell adhesion molecule that is expressed on circulating platelets, on leukocytes, and at the intercellular junctions of vascular endothelial cells and mediates the interactions of these cells during the process of transendothelial cell migration. The cDNA for PECAM-1 encodes an open reading frame of 738 amino acids (aa) that is organized into a 27- aa signal peptide, a 574-aa extracellular domain composed of 6 Ig homology units, and a relatively long cytoplasmic tail of 118 aa containing multiple sites for posttranslational modification and postreceptor signal transduction. To provide a molecular basis for the precise evaluation of the structure and function of this transmembrane glycoprotein, we have determined the organization of the human PECAM-1 gene. The PECAM-1 gene, which has been localized to human chromosome 17, is a single-copy gene of approximately 65 kb in length and is broken into 16 exons by introns ranging in size from 86 to greater than 12,000 bp in length. Typical of other members of the Ig superfamily, each of the extracellular Ig homology domains is encoded by a separate exon, consistent with PECAM-1 having arisen by gene duplication and exon shuffling of ancestral Ig superfamily genes. However, the cytoplasmic domain was found to be surprisingly complex, being encoded by seven short exons that may represent discrete functional entities. Alternative splicing of the cytoplasmic tail appears to generate multiple PECAM-1 isoforms that may regulate phosphorylation, cytoskeletal association, and affinity modulation of the mature protein. Finally, a processed pseudogene having 76% identity with PECAM- 1 cDNA was identified and localized to human chromosome 3. These findings should have important implications for structure/function analysis of PECAM-1 and its role in vascular adhesive interactions. 相似文献
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