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71.
E. Y. Liang W. W. M. Lam J. K. S. Woo C. A. van Hasselt C. Metreweli 《European radiology》1996,6(4):553-556
In order to study the features of sinonasal polyposis (SNP) on CT, 100 consecutive coronasal sinus CT examinations done for chronic inflamamtory sinonasal disease were reviewed. The CT findings of the 27 fully documented SNPs were analyzed. All our SNPs were bilateral. There was a strong tendency for extensive involvement. Nasal polyps were seen in 22 of 27 (81%); bony trabecular deossification in 23 of 27 (85%); widening of infundibulum in 26 of 27(96%). We discovered a new sign truncation of the bony middle turbinate, where the bulbous part of bony middle turbinate was missing, in 51 of 26 (58 %) of SNP patients without a previous history of middle turbinectomy, 12 of 15(80%) were bilateral. The one SNP patient (1 of 27) with previous middle turbinectomy was not regarded to be real truncation. Truncation of the bony middle turbinate is a characteristic and easily recognizable ancillary sign, and is not seen in other patterns of sinusitis. Together with other features on coronal sinus CT, this adds diagnostic confidence in diagnosing sinonasal polyposis.
Correspondence to: E. Y. Liang 相似文献
72.
Relation between genotype and phenotype in Swedish phenylketonuria and hyperphenylalaninemia patients 总被引:6,自引:0,他引:6
E. Svensson U. von Döbeln R. C. Eisensmith L. Hagenfeldt S. L. C. Woo 《European journal of pediatrics》1993,152(2):132-139
Phenylketonuria (PKU) and hyperphenylalaninemia (HPA) are caused mostly by an inherited (autosomal recessive) deficiency in hepatic phenylalanine hydroxylase (PAH) activity. More than 50 PAH mutations have ben reported. The goal of the present study was to examine the molecular basis for the clinical heterogeneity of Swedish PKU and HPA patients. Mutations were identified through allele-specific oligonucleotide hybridization or DNA sequencing on 128 of the 176 mutant alleles (73%). Three mutations (R408W, Y414C and IVS12) together accounted for 56% of all mutant alleles and ten relatively infrequent mutations were found on another 17% of all mutant alleles. Patients from 50 of the 88 families (57%) had identified mutations in both PAH genes and allowed use to compare the clinical effects of different combinations of PAH mutations. The in vitro activity of all of these mutations, including the newly identified G272X and L364, have been tested in a eukaryotic expression system. There was a strong relationship between the average in vitro PAH activity of the two mutant enzymes and both the phenylalanine tolerance and the neonatal pretreatment serum phenylalanine concentration. This confirms previous observations in Danish and German PKU patients that disease phenotype is a consequence of the nature of the mutations at the PAH locus and not significantly influenced by other loci. The sample population in the previous study did not, however, include mild HPA patients, and the observed correlation is thus restricted to severe and moderate mutant alleles. Since a comparatively high proportion of the Swedish patients were mildly affected, we have provided additional evidence that this correlation is valid throughout a continuous spectrum of clinical varieties. PAH genotyping could therefore help predict prognosis of a recently diagnosed PKU or HPA child. 相似文献
73.
Collman JP Woo LK 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(8):2592-2596
The synthesis and characterization of molybdenum(II) porphyrin dimers containing unbridged metal-metal quadruple bonds are presented. Variable temperature 300 MHz 1H NMR studies of meso-substituted derivatives provide novel solution evidence for both the existence of quadruple bonds and for a barrier to rotation about the metal-metal bonds in these complexes. The activation energy for this rotational process is 10.1 ± 0.5 kcal·mol-1. 相似文献
74.
Vision through cataracts 总被引:11,自引:0,他引:11
Contrast thresholds for a range of different spatial frequencies were compared with "acuity" tests for 10 subjects with uniocular senile cataract. The results indicate that the magnitude and extent of the intra-resolution limit abnormality vary dramatically in cataract subjects and that, for some subjects, vision is abnormal for objects of all sizes. This finding indicates that the present acuity evaluation of vision with cataracts is inadequate because, in some cases, it grossly overestimates the nature of the visual world of the cataract patient. 相似文献
75.
3'-Deoxybutirosin A (4), 5"-amino-3', 5"-dideoxybutirosin A (6), and 5"-amino-4', 5"-dideoxybutirosin A (7) were prepared by deoxygenation of the appropriate hydroxyl in suitably protected derivatives of butirosin A, using sequentially trifluoromethylsulfonylation, displacement with benzenethiolate, and hydrogenolysis. The structures of the compounds were confirmed by NMR spectroscopy, using 13C NMR and 1H NMR at up to 600 MHz. The compounds are broad-spectrum antibiotics active against resistant microorganisms which inactivate butirosin and related aminoglycosides by 3'-phosphorylation. 相似文献
76.
Degradation of ginseng saponins under mild acidic conditions 总被引:7,自引:0,他引:7
Ginseng saponins, ginsenosides Rg (1), Re and Rb (1), decomposed under mild acidic conditions to yield prosapogenins. The structures of the prosapogenins were investigated by (13)C-NMR spectroscopy and Rg (1)-prosapogenin II was shown to be a mixture of ginsenoside Rh (1), and its C-20 epimer, produced by hydrolysis followed by epimerization at C-20. Rg (1)-prosapogenin III, the other prosapogenin derived from ginsenoside Rg (1); was a C-25,26 hydrated derivative of Rg (1)-prosapogenin II. Re-prosapogenin II was identified as a mixture of ginsenoside Rg (2) and its C-20 epimer, and Re-prosapogenine III as a C-25,26 hydrated derivative of Re-prosapogenin II. 相似文献
77.
The extracts of sixty Korean plants were evaluated for their biological activities such as antitumor activities against Sarcoma 180, Leukemia SN-36 and Ehrlich ascites carcinoma, antimicrobial activities and behavioral observation in mice. The results are tabulated. 相似文献
78.
Expression of placental growth factor gene in lung cancer. 总被引:4,自引:0,他引:4
In Sook Woo Myung Jae Park Jae Ho Byun Young Seon Hong Kyung Shik Lee Young Suk Park Jung Ae Lee Young Iee Park Hye-Kyung Ahn 《Tumour biology》2004,25(1-2):1-6
Differences in the gene expression profiles in small cell lung cancers (SCLC) and non-small cell lung cancers (NSCLC) may explain their different clinical characteristics. The aims of this study were (1) to identify genes differentially expressed in SCLC and NSCLC using mRNA differential display, and (2) to determine the clinical relevance of such genes in lung cancer. RNA differential display using three SCLC and six non-SCLC cell lines was used to identify a differentially expressed gene. Differential expression of the gene was confirmed in additional lung cancer cell lines using RT-PCR. Immunohistochemical staining for the gene product was performed on paraffin-embedded tissue from lung cancer patients. We examined the relationship between the expression of the gene and clinical parameters, including disease stage, response to treatment and survival time. The placental growth factor (PGF) gene was identified as preferentially expressed in SCLC compared with NSCLC cell lines using mRNA differential display. Further analysis of 45 lung cancer cell lines using RT-PCR showed that the placental growth factor (PGF) gene was expressed in nine of 13 SCLC cell lines (69%) and five of 32 NSCLC cell lines (15.6%) (p < 0.001, Fisher's exact test). Immunohistochemistry using anti-PGF antibody on the paraffin blocks from lung cancer patients showed that PGF expression was significantly higher in SCLC than NSCLC tissue sections (32 vs. 5.6%, p = 0.041, Fisher's exact test). Expression of PGF protein did not correlate with disease stage, response to treatment or survival time in SCLC patients. The present study suggests there is higher expression of PGF in SCLC compared to NSCLC. It may be that higher expression of the angiogenic factor PGF contributes to differences between the progression of SCLC and NSCLC, especially in regard to the nature of SCLC metastasis. 相似文献
79.
Carbonic anhydrase IX expression, hypoxia, and prognosis in patients with uterine cervical carcinomas. 总被引:5,自引:0,他引:5
David Hedley Melania Pintilie Jennifer Woo Andrew Morrison Diana Birle Anthony Fyles Michael Milosevic Richard Hill 《Clinical cancer research》2003,9(15):5666-5674
PURPOSE: Hypoxia is associated with adverse outcome for a number of solid tumors, including cervical carcinomas. Direct pO(2) measurement requires specialized equipment and expertise that is not generally available. Immunohistochemical measurement of intrinsic tissue markers of hypoxia is an alternative approach. Recent studies suggest that carbonic anhydrase IX (CA IX), which is regulated via hypoxia-inducible factor 1, is a useful intrinsic marker of tumor hypoxia. EXPERIMENTAL DESIGN: Biopsies were obtained from 110 patients with locally advanced cervical carcinoma treated with radiotherapy or chemoradiotherapy. Tissue sections were labeled using an immunofluorescence technique and CA IX expression in the viable tumor area measured using a semiautomated fluorescence image analysis technique. Results were compared with direct pO(2) values obtained using an Eppendorf probe and to patient outcome. Intratumoral heterogeneity of CA IX expression was examined in a subgroup of patient who underwent multiple biopsies. RESULTS: The median percentage of tumor area staining for CA IX was 3.56 (range, 0.01-58.85). CA IX staining did not correlate with the Eppendorf pO(2) measurements. Whereas the latter values were predictive of patient outcome, the CA IX levels were not. Measurement of CA IX in multiple biopsies indicated that intratumoral heterogeneity accounted for 41% of the total variance in the data set. CONCLUSIONS: In contrast to some recent studies, we did not find significant associations between CA IX expression and tumor pO(2) levels or patient outcome in locally advanced carcinomas of the cervix. Probable explanations relate to the problems of sampling error using single biopsies and the existence of biological factors other than hypoxia that influence CA IX levels. 相似文献
80.