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Combined effects of radiotherapy and angiostatin gene therapy in glioma tumor model 总被引:28,自引:0,他引:28 下载免费PDF全文
Griscelli F Li H Cheong C Opolon P Bennaceur-Griscelli A Vassal G Soria J Soria C Lu H Perricaudet M Yeh P 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(12):6698-6703
The objective of the present study was to evaluate the antitumor effect of a defective adenovirus expressing a secretable angiostatin-like molecule (AdK3) in combination with radiotherapy in rat C6 gliomas s.c. preestablished into athymic mice. In vitro, the combination regimen was significantly (P < 0.001) more cytotoxic for human microcapillary endothelial cells than either treatment alone, whereas survival of C6 glioma cells was not affected in the conditions used. Radiotherapy and AdK3 gene delivery was then studied on well established C6 xenografts (165 +/- 70 mm(3)). In these tumors, AdK3 intratumoral injections had only a marginal effect. Interestingly, when experimental radiotherapy was added, significantly higher (P < 0.005), and possibly synergistic, antitumoral effects were observed that tightly correlated a marked decrease of intratumoral vascularization. The combination of radiotherapy and AdK3 intratumoral injections also revealed a significant (P < 0.05) inhibition of tumor growth as compared with either treatment alone for larger tumors (467 +/- 120 mm(3)). Altogether, these data emphasize the potential of combining a destructive strategy directed against the tumor cells with an anti-angiogenic approach to fight cancer. 相似文献
105.
Interaction between Helicobacter pylori and non-steroidal anti-inflammatory drugs in peptic ulcer bleeding 总被引:9,自引:0,他引:9
BACKGROUND: Helicobacter pylori and non-steroidal anti-inflammatory drugs (NSAIDs) are the two primary causes of peptic ulcer disease. How H. pylori and NSAIDs interact and influence the development of ulcer bleeding is still not clear. METHODS: A hospital-based, age- and sex-matched case-control study was conducted. Multivariate and stratified analyses were performed for further evaluation of the interaction between H. pylori and NSAIDs. RESULTS: Ninety-seven patients (52 gastric ulcers, 45 duodenal ulcers) and 97 non-ulcer controls were enrolled in the study. H. pylori and NSAIDs were both found to be independent risk factors for ulcer bleeding (H. pylori odds ratio, 2.22; 95% confidence interval (CI), 1.23-4.01; NSAIDs odds ratio, 4.57; 95% CI, 2.50-8.35). There was no synergistic effect. In contrast, a negative interaction was observed in the logistic regression and stratified analysis, although the difference was not significant (H. pylori adjusted odds ratio, 3.47; 95% CI, 1.73-6.95; NSAID adjusted odds ratio, 6.16; 95% CI, 3.14-12.09). CONCLUSION: H. pylori increases the risk of peptic ulcer bleeding but may play a protective role in NSAID users. 相似文献
106.
Shih-Chi Yeh Pao-Yuan Wang Yi-Wei Lou Kay-Hooi Khoo Michael Hsiao Tsui-Ling Hsu Chi-Huey Wong 《Proceedings of the National Academy of Sciences of the United States of America》2016,113(20):5592-5597
The cancer stem cells (CSCs) of glioblastoma multiforme (GBM), a grade IV astrocytoma, have been enriched by the expressed marker CD133. However, recent studies have shown that CD133− cells also possess tumor-initiating potential. By analysis of gangliosides on various cells, we show that ganglioside D3 (GD3) is overexpressed on eight neurospheres and tumor cells; in combination with CD133, the sorted cells exhibit a higher expression of stemness genes and self-renewal potential; and as few as six cells will form neurospheres and 20–30 cells will grow tumor in mice. Furthermore, GD3 synthase (GD3S) is increased in neurospheres and human GBM tissues, but not in normal brain tissues, and suppression of GD3S results in decreased GBM stem cell (GSC)-associated properties. In addition, a GD3 antibody is shown to induce complement-dependent cytotoxicity against cells expressing GD3 and inhibition of GBM tumor growth in vivo. Our results demonstrate that GD3 and GD3S are highly expressed in GSCs, play a key role in glioblastoma tumorigenicity, and are potential therapeutic targets against GBM.Glioblastoma multiforme (GBM) is extremely infiltrative and difficult to treat, and most patients develop recurrence after therapy. Over the past decade, many studies have suggested that bulk GBM tumors harbor cancer stem cells (CSCs) (1, 2), a distinct subpopulation of cancer cells that are able to initiate new tumors efficiently, have long-term self-renewal capacity, and survive better against chemo- or radiotherapy (2–4). CD133 has become a widely used marker for the enrichment of GBM CSCs (GSCs) and other tumor types (5–10). However, recent studies have shown that CD133 is not specific for GSCs because CD133− cells also possess tumor-initiating potential (11–13), indicating the need to identify more specific and exclusive markers for GSCs to facilitate our understanding of GSCs and therapeutic development against GBM. Several reports have proposed L1CAM, A2B5, integrin α6, MET, and CD15 as markers for GSCs (14–18). However, none of these protein markers could be used specifically to identify GSCs, and no study was reported with respect to glycans as potential markers, although glycan biosynthesis involves multiple genes and it is possible to create different structures in cancer progression. It is noted that ganglioside D2 (GD2) and ganglioside D3 (GD3) were found on the surface of neural stem cells (NSCs) and that stage-specific embryonic antigen 3 (SSEA3) and SSEA4 were found on embryonic stem cells and cancer cells (19–21), but there is no glycan marker found on the surface of GSCs.Gangliosides are sialic acid-containing glycosphingolipids (GSLs) that are most abundant in the nervous system (22). The expression levels and patterns of gangliosides during brain development shift from simple gangliosides, such as GM3 and GD3, to complex gangliosides, such as GM1, GD1a, GD1b, and GT1b (23, 24). Moreover, several unique ganglioside markers, including SSEA3, SSEA4, GD2, and GD3, have been identified in stem cells (19). GD3, a b-series ganglioside containing two sialic acids, is highly expressed in mouse and human embryonic NSCs (20, 25). In cancers, GD3 is highly accumulated in human primary melanoma tissues as well as in established melanoma cell lines (26), whereas human normal melanocytes express no or minimal levels of GD3 (27). Moreover, malignant gliomas contain higher levels of GD3, and its expression correlates with the degree of malignancy (28). GD3 is produced from the precursor GM3 by the activity of GD3 synthase (GD3S), which mediates the properties of CSCs through the c-MET signaling pathway and correlates with poor prognosis in triple-negative human breast tumors (29). These findings suggest that GD3 may play an important role in the transformation of normal cells into tumors, and imply that GD3 could be a cell surface marker for GSCs.This study was designed to identify glycan markers for the enrichment of GBM stem cells and then uses these enriched GBM stem cells to characterize tumorigenicity, their association with clinical GBM specimens, and their regulation in tumor progression. The results showed that GD2 and GD3 were positively stained on GBM neurospheres. We found that cells with high GD3 expression display functional characteristics of GSCs. Suppression of GD3S, a critical enzyme for GD3 synthesis, impeded neurosphere formation and tumor initiation. The expression of GD3S correlated with the grades of astrocytomas and mediated self-renewal through c-Met activation. Furthermore, a GD3 antibody was found to eliminate the GD3+ cells through complement-dependent cytotoxicity (CDC) in vitro and to suppress tumor growth in mice. These results suggest that GD3 could be a significant biomarker for GSCs, that CD3 could be combined with CD133 for the enrichment of GSCs, and that both GD3 and GD3S could be targets for the development of new therapies against GBM. 相似文献
107.
Jhen-Hao Jhan Hsin-Chih Yeh Yu-Han Chang Shiao-Jin Guu Wen-Jeng Wu Yii-Her Chou Ching-Chia Li 《Journal of diabetes and its complications》2018,32(7):688-692
Introduction
Androgen-deprivation therapy (ADT) is important in the treatment of prostate cancer. However, the relationship between ADT and the risk of diabetes remains unclear, and the association between duration and types of ADT has not been fully investigated.Aim
To examine the risk of developing type 2 diabetes mellitus (T2DM) in men who underwent ADT for prostate cancer.Methods
Data were collected retrospectively from the Longitudinal Health Insurance Database of Taiwan. In total, 4604 prostate cancer patients ≥40?years old who underwent ADT were included in the study cohort, and 4604 prostate cancer patients without ADT were included as controls, after adjusting for age and other comorbidities.Results
During the four-year follow-up period, the incidence of new-onset T2DM was 27.49 and 11.13 per 1000 person-years in the ADT and ADT-never cohorts, respectively. The ADT cohort was 2.19 times more likely to develop T2DM than the control group (95% CI 1.90–2.53, P?<?0.001). Furthermore, the association was particularly striking in the subgroup of patients receiving complete androgen blockade (adjusted HR 2.33, 95% CI 1.96–2.78, P?<?0.001).Conclusions
Men with prostate cancer who received ADT are at risk for developing diabetes. 相似文献108.
Joon-Mo Yang Chiye Li Ruimin Chen Bin Rao Junjie Yao Cheng-Hung Yeh Amos Danielli Konstantin Maslov Qifa Zhou K. Kirk Shung Lihong V. Wang 《Biomedical optics express》2015,6(3):918-932
Optical-resolution photoacoustic microscopy (OR-PAM) has become a major experimental tool of photoacoustic tomography, with unique imaging capabilities for various biological applications. However, conventional imaging systems are all table-top embodiments, which preclude their use in internal organs. In this study, by applying the OR-PAM concept to our recently developed endoscopic technique, called photoacoustic endoscopy (PAE), we created an optical-resolution photoacoustic endomicroscopy (OR-PAEM) system, which enables internal organ imaging with a much finer resolution than conventional acoustic-resolution PAE systems. OR-PAEM has potential preclinical and clinical applications using either endogenous or exogenous contrast agents.OCIS codes: (170.0170) Medical optics and biotechnology, (170.3880) Medical and biological imaging, (170.3890) Medical optics instrumentation, (170.5120) Photoacoustic imaging, (170.2150) Endoscopic imaging, (170.0180) Microscopy 相似文献
109.
Amy J. Mathers Nicole Stoesser Anna E. Sheppard Louise Pankhurst Adam Giess Anthony J. Yeh Xavier Didelot Stephen D. Turner Robert Sebra Andrew Kasarskis Tim Peto Derrick Crook Costi D. Sifri 《Antimicrobial agents and chemotherapy》2015,59(3):1656-1663
The global emergence of Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-Kp) multilocus sequence type ST258 is widely recognized. Less is known about the molecular and epidemiological details of non-ST258 K. pneumoniae in the setting of an outbreak mediated by an endemic plasmid. We describe the interplay of blaKPC plasmids and K. pneumoniae strains and their relationship to the location of acquisition in a U.S. health care institution. Whole-genome sequencing (WGS) analysis was applied to KPC-Kp clinical isolates collected from a single institution over 5 years following the introduction of blaKPC in August 2007, as well as two plasmid transformants. KPC-Kp from 37 patients yielded 16 distinct sequence types (STs). Two novel conjugative blaKPC plasmids (pKPC_UVA01 and pKPC_UVA02), carried by the hospital index case, accounted for the presence of blaKPC in 21/37 (57%) subsequent cases. Thirteen (35%) isolates represented an emergent lineage, ST941, which contained pKPC_UVA01 in 5/13 (38%) and pKPC_UVA02 in 6/13 (46%) cases. Seven (19%) isolates were the epidemic KPC-Kp strain, ST258, mostly imported from elsewhere and not carrying pKPC_UVA01 or pKPC_UVA02. Using WGS-based analysis of clinical isolates and plasmid transformants, we demonstrate the unexpected dispersal of blaKPC to many non-ST258 lineages in a hospital through spread of at least two novel blaKPC plasmids. In contrast, ST258 KPC-Kp was imported into the institution on numerous occasions, with other blaKPC plasmid vectors and without sustained transmission. Instead, a newly recognized KPC-Kp strain, ST941, became associated with both novel blaKPC plasmids and spread locally, making it a future candidate for clinical persistence and dissemination. 相似文献