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81.
Prediction and evaluation of brainstem function by auditory brainstem responses in patients with uncal herniation 总被引:2,自引:0,他引:2
S Nagao H Kuyama Y Honma F Momma T Nishiura T Murota M Suga T Tanimoto M Kawauchi A Nishimoto 《Surgical neurology》1987,27(1):81-86
Serial measurements of auditory brainstem-evoked responses (BERs) were conducted in 15 patients with supratentorial mass lesions. Significant prolongation of the latency of wave V BERs, which originates in the inferior colliculus, occurred when the intracranial pressure (ICP) approached 30 mmHg. In four of five patients whose BERs were measured before pupillary changes, a significant lengthening of wave V latency was observed prior to clinical manifestation of uncal herniation. These results suggest that immediate medical or surgical decompression of ICP should be performed when ICP approaches 30 mmHg with significant prolongation of wave V latency. 相似文献
82.
Correlation Between Vascular Endothelial Growth Factor C Expression and Lymph Node Metastasis in T1 Carcinoma of the Colon and Rectum 总被引:11,自引:0,他引:11
Maeda K Yashiro M Nishihara T Nishiguchi Y Sawai M Uchima K Onoda N Ohira M Ishikawa T Hirakawa K 《Surgery today》2003,33(10):736-739
Purpose. Vascular endothelial growth factor C (VEGF-C) is known to be associated with the development of the lymphatic vessel system. Recently, VEGF-C is thought to be correlated with lymph node metastasis in some malignant tumors. In this study, we investigated the correlation between VEGF-C expression and lymph node metastasis in early carcinoma of the colon and rectum.
Methods. Two hundred and twenty-one endoscopically biopsied specimens from patients with T1 colorectal carcinoma prior to operation were investigated by an immunohistochemical study.
Results. VEGF-C expression was more frequently observed in the tumors with nodal metastasis than in those without metastasis. Moreover, a multivariate analysis indicated that VEGF-C expression is an independent predictor of lymph node metastasis.
Conclusion. VEGF-C staining using endoscopically biopsied specimens prior to operation could be of use in the prediction of lymph node metastasis and in preoperative selection of treatment in patients with T1 colorectal carcinoma. 相似文献
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Negishi J Kawanami M Terada Y Matsuhashi C Ogami E Iwasaka K Hongo T 《Journal of the International Academy of Periodontology》2004,6(4):120-124
Lifestyle and socioeconomic status have been associated with the disease status of diabetic patients. However, there have been few reports on the relationship between these factors and the periodontal condition of diabetics. We assessed the association between disease status and lifestyle of diabetic patients and clinical features of advanced periodontitis such as deep probing depths and severe alveolar bone loss. Fifty-seven diabetic patients were examined in this study. Clinical assessment of probing pocket depth and radiographic alveolar bone loss was performed. Data regarding diabetic status and lifestyle of the diabetic patients were also recorded and statistically analysed by logistic regression. Drinking habits and high values of hemoglobin A1c (HbA1c) (>9.0%) were significantly associated with deep probing depth. The odds ratios (OR) of these factors were 7.72 (95% confidence interval (CI), 1.80 to 33.19), and 6.10 (95% CI = 1.23 to 30.25), respectively. Presence of complications such as retinopathy (OR = 8.86, 95% CI, 1.99 to 39.40), irascible behaviour (OR = 8.40, 95% CI = 1.33 to 53.17) and high value of HbA1c (OR = 4.94, 95% CI = 1.14 to 21.46) were significantly related to mean advanced alveolar bone loss. Only the high value of HbA1c (OR = 3.53, 95% CI = 1.06 to 11.73) was detected as a significant factor related to advanced periodontitis, characterised by more than 50% mean alveolar bone loss, or two or more teeth with probing depth greater than 6 mm. In conclusion, drinking habit and irascible behaviour are correlated with the periodontal disease condition of diabetic patients, in addition to a high value of HbA1c (>9.0%). Lifestyle and psychosocial stress may affect the periodontal disease status of diabetic patients. 相似文献
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Genomewide identification of target genes of histone methyltransferase dG9a during Drosophila embryogenesis 下载免费PDF全文
88.
Honma M 《Environmental and molecular mutagenesis》2005,45(2-3):162-176
Loss of heterozygosity (LOH) is a critical event in the development of human cancers. LOH is thought to result from either a large deletion or recombination between homologous alleles during repair of DNA double-strand breaks (DSBs). These types of genetic alterations produce mutations in the TK gene mutation assay, which detects a wide mutational spectrum, ranging from point mutations to LOH-type mutations. TK6, a human lymphoblastoid cell line, is heterozygous for the thymidine kinase (TK) gene and has a wild-type p53 gene. The related cell lines, TK6-E6 and WTK-1, which are p53-deficient and p53-mutant (Ile237), respectively, are also heterozygous for the TK gene and LOH-type mutation can be detected in these cells. Therefore, comparative studies of TK mutation frequency and spectrum with these cell lines are useful for elucidating the role of p53 in generating LOH and maintaining genomic stability in human cells. We demonstrate here that LOH and its associated genomic instability strongly depend on the p53 status in these cells. TK6-E6 and WTK-1 are defective in the G1/S checkpoint and in apoptosis. Unrepaired DSBs that escape from the checkpoint can potentially initiate genomic instability after DNA replication, resulting in LOH and a variety of chromosome changes. Moreover, genomic instability is enhanced in WTK-1 cells. It is likely that the mutant p53 protein in WTK-1 cells increases LOH in a dominant-negative manner due to its abnormal recombination capacity. We discuss the mutator phenotype and genomic instability associated with p53 inactivation with the goal of elucidating the mechanisms of mutation and DNA repair in untargeted mutagenesis. 相似文献
89.
Hoshino Y Honma S Jones RW Ross J Santos N Gentsch JR Kapikian AZ Hesse RA 《Virology》2005,332(1):177-188
Of five globally important VP7 (G) serotypes (G1-4 and 9) of group A rotaviruses (the single most important etiologic agents of infantile diarrhea worldwide), G9 continues to attract considerable attention because of its unique natural history. Serotype G9 rotavirus was isolated from a child with diarrhea first in the United States in 1983 and subsequently in Japan in 1985. Curiously, soon after their detection, G9 rotaviruses were not detected for about a decade in both countries and then reemerged in both countries in the mid-1990s. Unexpectedly, however, such reemerged G9 strains were distinct genetically and molecularly from those isolated in the 1980s. Thus, the origin of the reemerged G9 viruses remains an enigma. Sequence analysis has demonstrated that the G9 rotavirus VP7 gene belongs to one of at least three phylogenetic lineages: lineage 1 (strains isolated in the 1980s in the United States and Japan), lineage 2 (strains first isolated in 1986 and exclusively in India thus far), and lineage 3 (strains that emerged/reemerged in the mid-1990s). Currently, lineage 3 G9 viruses are the most frequently detected G9 strains globally. We characterized a porcine rotavirus (A2 strain) isolated in the United States that was known to belong to the P[7] genotype but had not been serotyped by neutralization. The A2 strain was found to bear serotype G9 and P9 specificities as well as NSP4 [B] and subgroup I characteristics. By VP7-specific neutralization, the porcine G9 strain was more closely related to lineage 3 viruses than to lineage 1 or 2 viruses. Furthermore, by sequence analysis, the A2 VP7 was shown to belong to lineage 3 G9. These findings raise intriguing questions regarding possible explanations for the emergence of variations among the G9 strains. 相似文献
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