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排序方式: 共有661条查询结果,搜索用时 15 毫秒
651.
AIM:To isolate,characterize and investigate the antifungal activity of the root bark of Psorospermum corymbiferum(Clusiaceae).METHODS:The finely ground root bark of Psorospermum corymbiferum was cold-extracted by percolation with 98% ethanol(5.0 L) for two weeks.The ethanol extract was macerated with n-hexane,chloroform,ethylacetate and methanol successively to give the respective solvent extracts.Fractionation of the extract was done using column chromatography on silica gel with cyclohexene:ethylacetate(1... 相似文献
652.
Kang Z Liu L Spangler R Spear C Wang C Gulen MF Veenstra M Ouyang W Ransohoff RM Li X 《The Journal of neuroscience》2012,32(24):8284-8292
Cuprizone inhibits mitochondrial function and induces demyelination in the corpus callosum, which resembles pattern III lesions in multiple sclerosis patients. However, the molecular and cellular mechanism by which cuprizone induces demyelination remains unclear. Interleukin-17 (IL-17) secreted by T helper 17 cells and γδT cells are essential in the development of experimental autoimmune encephalomyelitis. In this study, we examined the importance of IL-17 signaling in cuprizone-induced demyelination. We found that mice deficient in IL-17A, IL-17 receptor C (IL-17RC), and adaptor protein Act1 (of IL-17R) all had reduced demyelination accompanied by lessened microglial and polydendrocyte cellular reactivity compared with that in wild-type mice in response to cuprizone feeding, demonstrating the essential role of IL-17-induced Act1-mediated signaling in cuprizone-induced demyelination. Importantly, specific deletion of Act1 in astrocytes reduced the severity of tissue injury in this model, indicating the critical role of CNS resident cells in the pathogenesis of cuprizone-induced demyelination. In cuprizone-fed mice, IL-17 was produced by CNS CD3(+) T cells, suggesting a source of IL-17 in CNS upon cuprizone treatment. 相似文献
653.
Gulgun Tahan Erman Aytac Huseyin Aytekin Feyza Gunduz Gulen Dogusoy Seval Aydin Veysel Tahan Hafize Uzun 《Canadian journal of surgery》2011,54(5):333-338
Background
Increased free radical production, decreased antioxidant capacity and excessive inflammation are well-known features in the pathogenesis of inflammatory bowel disease. Vitamin E is a powerful antioxidant and a scavenger of hydroxyl radicals, and it has been shown to have anti-inflammatory activities in tissues. We investigated the effects of vitamin E on inflammatory activities using an acetic acid (AA)–induced ulcerative colitis model in rats.Methods
Wistar rats were divided into 4 groups. Acetic acid was given to 2 groups of animals to induce colitis while the other 2 groups received saline intrarectally. One AA-induced colitis group and 1 control group received vitamin E (30 U/kg/d) intraperitoneally and the pair groups received saline. After 4 days, we evaluated colonic changes biochemically by measuring proinflammatory cytokine levels in tissue homogenates and by histopathologic examination.Results
Acetic acid caused colonic mucosal injury, whereas vitamin E administration suppressed these changes in the AA-induced colitis group (p < 0.001). Administration of AA resulted in increased levels of tumour necrosis factor-α, interleukin-1β, interleukin-6, myeloperoxidase and malondialdehyde, and decreased levels of glutathione and superoxide dismutase; vitamin E reversed these effects (all p < 0.001).Conclusion
Our study proposes that vitamin E is an effective anti-inflammatory and antioxidant and may be a promising therapeutic option for ulcerative colitis. 相似文献654.
G Merino R Real MF Baro L Gonzalez-Lobato JG Prieto AI Alvarez MM Marques 《Drug metabolism and disposition》2009,37(1):5-9
ATP-binding cassette transporter ABCG2 [breast cancer resistance protein (BCRP)] is a member of the ABC transporter superfamily that actively extrudes xenotoxins from cells and is a major determinant of the bioavailability of many compounds. ABCG2 expression is strongly induced during lactation in the mammary gland and is related to the active secretion of drugs into the milk. The presence of drug residues and environmental pollutants in milk is an outstanding problem for human milk consumption and milk industrial processes, involving important risks to public health and the dairy industry. In cows, a single nucleotide polymorphism (SNP) in this protein has been described previously (Tyr581) and is associated with higher fat and protein percentages and lower milk yield. However, whether this amino acid substitution affects ABCG2-mediated drug transport in cows, including milk secretion, required further exploration. We cloned the two variants of bovine ABCG2 and evaluated the effect of this SNP on mitoxantrone accumulation assays performed in ovine primary fibroblasts transiently expressing either of the variants. It is interesting to note that statistically significant differences in activity between both variants were observed, and the Ser581 variant was related with an increased efflux activity. In addition, we demonstrated that genistein is a very good inhibitor of bovine ABCG2 and identified new inhibitors of the transporter, such as the macrocyclic lactones, ivermectin, and selamectin. Moreover, the inhibitory effect of these compounds on human and murine ABCG2 homologs was confirmed using transduced Marbin-Dabin canine kidney II cells. These findings may have important implications regarding the presence of drug residues in milk and drug interactions affecting the pharmacological behavior of ABCG2 substrates. 相似文献
655.
Elegance TP Lam Cindy LK Lam CL Lai MF Yuen Daniel YT Fong Thomas MK So 《Health and quality of life outcomes》2009,7(1):52
Background
Few studies have evaluated the health-related quality of life (HRQOL) of Southern Chinese with chronic hepatitis B (CHB) infection. 相似文献656.
657.
658.
659.
Shashanka Rajendrachari Vinayak Adimule Mahir Gulen Farshid Khosravi Kiran Kenchappa Somashekharappa 《Materials》2022,15(21)
High entropy alloys (HEA) are one of the modern-era alloys accelerating with greater velocity because of their excellent properties and different applications. In the present paper, we have successfully fabricated HEA (23Fe-21Cr-18Ni-20Ti-18Mn) powders by ball milling the elemental Fe, Cr, Ni, Ti, and Mn powders for 15 h. The advancement of the milling process and phase transformation of HEAs were studied by using X-ray diffraction (XRD) and scanning electron microscope (SEM). The crystallite size and the lattice strain of the HEA were calculated by using the Williamson-Hall (W-H) equation and the values were found to be 7 nm and 0.0176%, respectively. Similarly, the true lattice parameter was calculated using the Nelson–Riley (N-R) extrapolation method, and the value was found to be 3.544 Å. We have successfully investigated the electrochemical response of 15 h ball milled 23Fe-21Cr-18Ni-20Ti-18Mn HEA powders to determine the ascorbic acid (AA) using cyclic voltammetry. We have modified the carbon paste electrode with ball milled HEA of concentrations 0, 2, 4, 6, 8, and 10 mg, and among them, 8 mg HEA modified carbon paste electrode (HEA-MCPE) depicted the highest current sensitivity. We reported the effect of modifier concentration, analyte concentration, scan rate, and pH on the oxidation peak of AA. The electrochemical active surface area of carbon paste and MCPE was calculated using the Nernst equation and the values were found to be 0.0014 cm2 and 0.0027 cm2, respectively. The fabricated HEA-MCPE showed excellent current sensitivity, stability, anti-fouling, and selectivity. 相似文献
660.
Ugur Orhan Muge Gulen Salim Satar Selen Acehan Hakan Nazik Nurdan Unlu Mustafa Gediklioglu Cem Isikber Ahmet Sonmez Gökben Oral Sonmez 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2023,27(3):580-586