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71.
72.
Vijayakumar Raju Sundar Ramanathan Raman Manjeri Lakshmanan Natarajan Subramanian 《Indian Journal of Thoracic and Cardiovascular Surgery》2010,26(2):167-169
Secondary involvement of the heart and pericardium by systemic lymphoma is well documented. Primary Cardiac lymphomas (PCL) are extremely rare. Incidence of PCL is increasing in immunocompromised patients. However PCL in immunocompetent is much rarer. We report such a case of PCL in an immunocompetent elderly female masquerading as right atrial myxoma causing complete heart block which was surgically debulked successfully. Her rhythm resumed to Sinus rhythm following surgical debulking. Immunohistochemistry of the excised tumour revealed Diffuse Large B cell lymphoma. With combination chemotherapy, she is symptom free on six months follow up. 相似文献
73.
Kevil CG Hicks MJ He X Zhang J Ballantyne CM Raman C Schoeb TR Bullard DC 《The American journal of pathology》2004,165(2):609-616
Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by immune complex-mediated tissue injury. Many different adhesion molecules are thought to participate in the development of SLE; however, few studies have directly examined the contributions of these proteins. Here we demonstrate that LFA-1 plays an essential role in the development of lupus in MRL/MpJ-Fas(lpr) mice. Mice deficient in LFA-1, but not Mac-1, showed significantly increased survival, decreased anti-DNA autoantibody formation, and reduced glomerulonephritis. The phenotype of the LFA-1-deficient mice was similar to that observed in beta(2) integrin-deficient (CD18-null) MRL/MpJ-Fas(lpr) mice, suggesting a lack of redundancy among the beta(2) integrin family members and other adhesion molecules. These studies identify LFA-1 as a key contributor in the pathogenesis of autoimmune disease in this model, and further suggest that therapeutic strategies targeting this adhesion molecule may be beneficial for the treatment of SLE. 相似文献
74.
B6.Sle1 mice, congenic for the NZM2410-derived lupus susceptibility locus, Sle1 on chromosome 1 exhibit many of the features seen in human lupus including activated lymphocytes and high titers of antinuclear autoantibodies. Among the different surface molecules that were aberrantly expressed on the B6.Sle1 lymphocytes was Ly-6A/E. Splenic B- and T-lymphocytes but not myeloid cells from B6.Sle1 mice exhibited enhanced levels of Ly-6A/E compared to B6 controls. In particular, MZ B cells, GC B cells and B-cell blasts expressed the highest levels of Ly-6A/E in both strains, with the levels being even higher on B6.Sle1 derived cells. Following stimulation with LPS or anti-IgM, there was a profound up-regulation in Ly-6A/E, particularly on MZ B cells and B-cell blasts. CD4 and CD8 T cells also up-regulated Ly-6A/E after stimulation with anti-CD3 and anti-CD28. These studies were extended to additional autoimmune strains including B6.Sle3, B6.Sle1.lpr and BXSB. Importantly, Ly-6A/E levels on lymphocytes were commensurate with the degree of disease exhibited by these lupus strains. Finally, it appears that increased interferon levels, in addition to antigen receptor stimulation, may also be a factor accounting for elevated Ly-6A/E in lupus. Given these observations it is important to elucidate the functional role of Ly-6A/E in lupus in future studies. 相似文献
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76.
An alkali-free series of bioactive glasses has been designed and developed in the glass system CaO-MgO-SiO2-P2O5-CaF2 along the diopside (CaMgSi2O6)-fluorapatite (Ca5(PO4)3F)-tricalcium phosphate (3CaO·P2O5) join. The silicate network in all the investigated glasses is predominantly coordinated in Q2 (Si) units, while phosphorus tends to remain in an orthophosphate (Q0) environment. The in vitro bioactivity analysis of glasses has been made by immersion of glass powders in simulated body fluid (SBF) while chemical degradation has been studied in Tris-HCl in accordance with ISO-10993-14. Some of the investigated glasses exhibit hydroxyapatite formation on their surface within 1-12 h of their immersion in SBF solution. The sintering and crystallization kinetics of glasses has been investigated by differential thermal analysis and hot-stage microscopy, respectively while the crystalline phase evolution in resultant glass-ceramics has been studied in the temperature range of 800-900 °C using powder X-ray diffraction and scanning electron microscopy. The alkaline phosphatase activity and osteogenic differentiation for glasses have been studied in vitro on sintered glass powder compacts using rat bone marrow mesenchymal stem cells. The as-designed glasses are ideal candidates for their potential applications in bone tissue engineering in the form of bioactive glasses as well as glass/glass-ceramic scaffolds. 相似文献
77.
Devinder K.A. Singh Bala S. Rajaratnam Vijayakumar Palaniswamy Hannah Pearson Vimal P. Raman Pei Sien Bong 《Maturitas》2012
Objective
The objective of this study was to quantify the effectiveness of virtual reality balance games (VRBG) to decrease risk and fear of falls among women.Methods
Thirty six community dwelling women aged 56 and above were randomly divided into experimental (exercises using VRBG focus on improving balance) and control (conventional balance exercises) groups. Both groups attended a twice 6 weekly exercise session for an hour. Risk and fear of falls were measured with Physiological Profile Approach (PPA) and Activity Specific Balance Scale (ABC-6). Pre and post intervention differences between the groups were examined using two way repeated measures ANOVA.Results
Both VRBG and conventional balance exercise groups had significant decrease in PPA (p < 0.001) and ABC-6 (p < 0.01) after the interventions. However, no significant effects were demonstrated between the groups in PPA (p = 0.18) and ABC-6 (p = 0.25) post intervention. Time and group interaction effect were not significant for PPA (p = 0.18) and ABC-6 (p = 0.45).Conclusions
Practising VRBG can increase balance confidence and decrease risk of falls among community dwelling women. 相似文献78.
Marise R. Heerma van Voss Willemijne A. M. E. Schrijver Natalie D. ter Hoeve Laurien D. Hoefnagel Quirine F. Manson Elsken van der Wall Venu Raman Paul J. van Diest Dutch Distant Breast Cancer Metastases Consortium 《Clinical & experimental metastasis》2017,34(1):85-92
Metastatic breast cancer remains one of the leading causes of death in women and identification of novel treatment targets is therefore warranted. Functional studies showed that the RNA helicase DDX3 promotes metastasis, but DDX3 expression was never studied in patient samples of metastatic cancer. In order to validate previous functional studies and to evaluate DDX3 as a potential therapeutic target, we investigated DDX3 expression in paired samples of primary and metastatic breast cancer. Samples from 79 breast cancer patients with distant metastases at various anatomical sites were immunohistochemically stained for DDX3. Both cytoplasmic and nuclear DDX3 expression were compared between primary and metastatic tumors. In addition, the correlation between DDX3 expression and overall survival was assessed. Upregulation of cytoplasmic (28%; OR 3.7; p?=?0.002) was common in breast cancer metastases, especially in triple negative (TN) and high grade cases. High cytoplasmic DDX3 levels were most frequent in brain lesions (65%) and significantly correlated with high mitotic activity and triple negative subtype. In addition, worse overall survival was observed for patients with high DDX3 expression in the metastasis (HR 1.79, p?=?0.039). Overall, we conclude that DDX3 expression is upregulated in distant breast cancer metastases, especially in the brain and in TN cases. In addition, high metastatic DDX3 expression correlates with worse survival, implying that DDX3 is a potential therapeutic target in metastatic breast cancer, in particular in the clinically important group of TN patients. 相似文献
79.
80.
Subramaniam Puvaneswary Hanumantha Rao Balaji Raghavendran Nurul Syuhada Ibrahim Malliga Raman Murali Azhar Mahmood Merican T. Kamarul 《International journal of medical sciences》2013,10(12):1608-1614
The objective of this study was to compare the morphological and chemical composition of bone graft (BG) and coral graft (CG) as well as their osteogenic differentiation potential using rabbit mesenchymal stem cells (rMSCs) in vitro. SEM analysis of BG and CG revealed that the pores in these grafts were interconnected, and their micro-CT confirmed pore sizes in the range of 107-315 µm and 103-514 µm with a total porosity of 92% and 94%, respectively. EDS analysis indicated that the level of calcium in CG was relatively higher than that in BG. FTIR of BG and CG confirmed the presence of functional groups corresponding to carbonyl, aromatic, alkyl, and alkane groups. XRD results revealed that the phase content of the inorganic layer comprised highly crystalline form of calcium carbonate and carbon. Atomic force microscopy analysis showed CG had better surface roughness compared to BG. In addition, significantly higher levels of osteogenic differentiation markers, namely, alkaline phosphatase (ALP), Osteocalcin (OC) levels, and Osteonectin and Runx2, Integrin gene expression were detected in the CG cultures, when compared with those in the BG cultures. In conclusion, our results demonstrate that the osteogenic differentiation of rMSCs is relatively superior in coral graft than in bone graft culture system. 相似文献