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91.
Serum antibodies to gangliosides in Guillain-Barré syndrome   总被引:10,自引:0,他引:10  
To determine whether antibodies to acidic glycolipids of nervous tissue are present in patients with Guillain-Barré syndrome (GBS), sera from patients with GBS and appropriate control subjects were tested by a thin-layer chromatogram overlay technique. Chromatograms on which the whole ganglioside fractions from peripheral nerve and brain had been separated were overlaid with appropriate dilutions of the patients' sera (1:100 or greater), and antibody binding was revealed with a radiolabeled or peroxidase-labeled second antibody. Antibodies to ganglioside antigens were detected in 5 of 26 patients with GBS. IgG antibodies in 1 patient reacted strongly with LM1 (sialosyl paragloboside), the major ganglioside of human peripheral nervous system myelin, and its hexaose analog (sialosyl lactosaminyl paragloboside), a minor ganglioside of human peripheral nervous system myelin. The antibody titer in this patient fell 8-fold over 6 weeks coincident with clinical improvement. IgG from 2 other patients with GBS reacted with GD1b ganglioside, and the antibody titers in these patients also decreased substantially with clinical improvement. IgM antibodies in the sera from 2 other patients reacted with GD1a and GT1b gangliosides, which have a shared terminal carbohydrate sequence. Antibodies to gangliosides were not detected in the sera from 19 patients with other neurological diseases or from 10 normal subjects, and the frequency with which antiganglioside antibodies occurred in the patients with GBS was significantly greater than that in the combined control subjects (p less than 0.01). The results demonstrate relatively high levels of antibodies to gangliosides in some GBS patients.  相似文献   
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An 18-month-old girl presented with high fever and vomiting. Pneumothorax and a cystic formation in the right hemithorax were found on a chest radiograph. The cyst measuring 10 x 10 x 8 cm was resected by a simple wedge resection. Histology revealed a complicated bronchogenic cyst with abscess formation.  相似文献   
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Presence of the apolipoprotein E (APOE) 4 allele has been associated with increased incidence and faster progression of neurodegenerative diseases, poorer recovery from neurologic insult, and decreased cognitive function in the well-elderly. The specific association between APOE genotype and recovery from severe traumatic brain injury (TBI) is conflicting with many groups finding the APOE 4 allele to be associated with poorer outcome while others have found no association. The purpose of this study was to investigate the association between APOE 4 allele presence and recovery during the two years after injury from severe TBI in light of other potential covariates, such as age, race, gender, hypotension or hypoxia before hospital admission and severity of injury. APOE genotype was determined for 123 subjects with severe TBI. Glasgow outcome score (GOS) and mortality were collected at 3, 6, 12, and 24 months after injury. Results showed individuals improved over the two year period following injury and those with the 4 allele had a slower recovery rate than those without the APOE 4 allele over the two year period. We did not however find significant differences in GOS at individual time points when controlling for other covariates. Our findings suggest that APOE 4 allele presence influences recovery rate from severe TBI independent of other covariates. The findings of this study are unique in that they address not only the relationship between APOE 4 allele presence and outcome from severe TBI, but also describe differences in trajectory of recovery by APOE 4 allele presence.  相似文献   
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BACKGROUND AND OBJECTIVE: This study aimed to assess the effectiveness of the UK National Guidelines for identifying patients with potentially malignant oral disease which were introduced in 2000. DESIGN: Retrospective audit. SETTING: The oral medicine unit in a university teaching hospital in London. METHODS: All new referrals over a one year period were retrospectively reviewed in a departmental audit to evaluate guideline effectiveness. Reasons for referral and final diagnosis were compared in a randomly selected sub-population. RESULTS: Four hundred and eighty-seven of 901 new patients referred were classified as having potentially malignant disease from the referral letter. In a randomly selected subgroup of 241 patients, 18 actually had malignant (8) or dysplastic lesions (10). Of 75 patients referred with a persistent oral ulcer, only nine were actually malignant or dysplastic. Eight of 116 patients referred with a white patch and none with red patches were found to have dysplastic or malignant lesions. The criteria failed to identify three carcinomas and two severely dysplastic lesions (15% of the malignant or dysplastic lesions). All of the latter had been referred by primary care physicians with orofacial pain of unknown cause. CONCLUSIONS: UK National Guidelines discriminate poorly between potentially malignant and other oral mucosal disease.  相似文献   
98.
OBJECTIVE: Low serum paraoxonase 1 (PON1) activity determined with paraoxon as substrate has been found to be associated with coronary artery disease. This study was undertaken to examine the relationship of PON1 activity and genotype to risk of systemic lupus erythematosus (SLE). METHODS: The impact of 7 PON1 single-nucleotide polymorphisms (SNPs) was analyzed in relation to PON1 activity, SLE risk, lupus nephritis, antiphospholipid antibody (aPL) positivity, and carotid vascular disease in 380 SLE patients (334 white, 46 black) and 497 controls (455 white, 42 black). RESULTS: Compared with findings in controls, PON1 activity with paraoxon substrate was reduced both in white lupus patients (mean +/- SEM 618.9 +/- 24.0 units/liter versus 719.6 +/- 24.6 units/liter; P = 0.007) and in black lupus patients (991.1 +/- 82.7 units/liter versus 1,164.3 +/- 101.4 units/liter; P = 0.2711). Low PON1 activity in SLE was not associated with the occurrence of aPL, carotid vascular disease, or the use of immunosuppressive drugs. In multiple regression analyses, the Q192R SNP was found to be independently associated with PON1 activity and explained 28% and 41% of the variation in PON1 activity in white patients and black patients, respectively. Stratification of the lupus sample by presence (n = 81) or absence (n = 247) of renal disease revealed significant associations with 3 promoter SNPs, with odds ratios of 3.82 (95% confidence interval [95% CI] 1.49-9.82, P = 0.005), 3.41 (95% CI 1.35-8.61, P = 0.009), and 2.17 (95% CI 1.01-4.68, P = 0.049). CONCLUSION: To our knowledge, this is the first study to assess the role of PON1 activity in SLE risk in a large biracial sample from the US. Our data indicate that low PON1 activity determined with paraoxon substrate is independently associated with SLE and that certain PON1 SNPs are associated with lupus nephritis.  相似文献   
99.
[carboxyl14C]Celivarone was synthesised from barium [14C]carbonate with overall radiochemical yields in the range 49–53%. The synthetic route involves [14C]carbonylation methodology, which both decreased the number of synthetic steps and increased the yields obtained from previous synthetic routes.  相似文献   
100.
A new chromone named as 5,4′-dihydroxy-7-methyl 3-benzyl chromone (1) along with three known flavonoid compounds as unsubstituted flavone, kaempferol-3-o-rhamnoside and quercetin-3-o-arabinoside have been isolated from the leaves of Cassia nodosa. Their structures have been established by means of chemical and spectral evidences (IR, UV, 1H-NMR, 13C-NMR and mass spectra).  相似文献   
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