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排序方式: 共有702条查询结果,搜索用时 218 毫秒
241.
Si-qi Feng Jian-liang Geng Run-bin Sun Jing-qiu Huang Zhao-yi Tan Cai-xia Yan Ji-ye AA Guang-ji Wang 《中草药(英文版)》2017,9(4):335-343
Objective Salvianolic acid A(SAA) has a significant protective effect on ischemia/reperfusion injury of brain. However, it is not clear for SAA to exert its cerebral protection by targeting at the microvascular endothelial cells of blood brain barrier(BBB). Our previous study demonstrated that SAA could hardly pass through the BBB. This present study was therefore designed to investigate the protective effect of SAA on brain microvascular endothelial cells(BMECs) induced by deprivation and reperfusion with oxygen-glucose. Methods Rat BMECs were treated with oxygen glucose deprivation(OGD), followed by reperfusion(OGD/R). Cell viability was assessed by MTT and the content of reactive oxygen species(ROS) in cells after OGD/R in the absence or presence of SAA. GC-MS based metabolomic platform was applied to evaluate the regulation of SAA on the cellular metabolic perturbation induced by OGD/R. Results OGD/R significantly increased the production of intracellular reactive oxygen species(ROS), and decreased the activity of cells. SAA significantly reduced ROS and improve the cell viability. Metabolomic study revealed distinct perturbation of metabolic pathways of energy metabolism in the BMEC induced by OGD/R, while SAA significantly regulated the perturbed metabolism involved in energy metabolism pathways, especially for intermediates in TCA cycle. Conclusion SAA shows protective effects on BMECs involved in central nervous system. 相似文献
242.
The effect of different doses of ultraviolet B irradiation (UVR) on the proliferative responses of Balb/c spleen cells has been tested. In 72-hour cultures, there was dose-dependent suppression of proliferation in response to phytohemagglutinin (PHA). Cell viability after UVR was found to be reduced in a dose- and time-dependent manner. Proliferation increased by greater than 100 percent after low-dose (20 J/m2) UVR when either normal or gamma-irradiated peritoneal cells were added to the cultures, but not at higher doses. Delaying UVR until 24 hours after stimulation of cultures with PHA did not substantially increase [3H]-thymidine uptake. Stimulation of mixtures of UV-irradiated and control cells or incorporation of medium conditioned with UV-irradiated cells provided no evidence of suppression of proliferation. The accessory cell population is an important target for UVR, but cells are physically damaged to the extent that, at higher doses, the response to PHA stimulation cannot be restored. 相似文献
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246.
S Sudarsanan S Chaudhary AA Pawar K Srivastava 《Medical Journal Armed Forces India》2007,63(3):259-263
In India 30,000 people die and 1,25,000 become disabled due traumatic brain injury (TBI). The psychiatric sequalae of TBI can be acute and chronic. Chronic sequalae of TBI are usually ignored and may take the form of defects of cognition, memory, perception, language or intelligence. It may also lead to inappropriate aggression, sexual behaviour, personality change, mood changes, neurosis and psychosis. Neuropsychological assessment of TBI can be pharmacological or behavioural. Survivors of TBI are referred to a walking wounded and require to be cared for.Key Words: Traumatic brain injury, Psychiatric sequelae, Cognitive sequelae, Personality change, Post-concussional syndrome 相似文献
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248.
Plateletpheresis: comparison of platelet yields, processing time, and white cell content with two apheresis systems 总被引:2,自引:0,他引:2
Two apheresis systems (COBE Spectra and Fenwal CS-3000 Plus with TNX-6 chamber [CS-3000 Plus]) were compared by using their yield predictors and maximum processing times in regard to platelet yields and processing times (n = 200 each). Platelet yields (n = 50 each) and white cell (WBC) content (n = 20 each) from procedures using the current software revision (3.6) on the Spectra and various interface offset (IO) settings on the CS-3000 Plus were also compared. Significantly higher median platelet yields (4.88 [range, 1.84-9.97] vs. 4.57 [range, 2.82-9.20] × 10(11) platelets) and frequency of components with > or = 6.0 × 10(11) platelets (31.5 vs. 21.5%) were found with the Spectra. In the study with Spectra and the CS-3000 Plus IO settings, IO-10 and IO-13, overall, produced the most platelets, although the differences were not significant. All Spectra collections tested had < 5 × 10(8) WBCs, and, depending on the software revision, had either 85 percent (revision 3.6) or 100 percent (revision 2.5) of components with < 5 × 10(6) WBCs. To ensure that 100 percent of components contained < 5 × 10(8) WBCs when the CS-3000 Plus was used, IO settings of 10 or less were required, and to ensure components with < 5 × 10(6) WBCs, only IO-6 could be used. Spectra and CS-3000 Plus were capable of collecting large doses of platelets (up to the equivalent of 18 units) in processing times of 67 to 100 minutes with < 5 × 10(6) WBCs. 相似文献
249.
RJ Brashear ; MA Winkler ; JD Schur ; H Lee ; JD Burczak ; HJ Hall ; AA Pan 《Transfusion》1995,35(3):213-218
BACKGROUND: Chagas' disease or American trypanosomiasis, caused by infection with Trypanosoma cruzi, is a significant health problem in Latin America. In the United States, transfusions of T. cruzi- contaminated blood from Latin American immigrants may represent the major source of Chagas' disease. STUDY DESIGN AND METHODS: A new enzyme immunoassay (EIA) for the detection of antibody to T. cruzi was evaluated in the sera of blood donors from the southwestern and western regions of the United States. Serum samples had been screened and were negative for all tests required. Specimens that were repeatedly reactive in the Chagas antibody EIA were analyzed for seroreactivity by a confirmatory EIA and by radioimmunoprecipitation assay. RESULTS: Fourteen of the 13,309 donor samples (0.105%) were confirmed as being positive for antibody to T. cruzi. The Chagas antibody EIA showed improved sensitivity over the Chagas IgG enzyme-linked immunosorbent assay and two indirect hemagglutination assays. The Chagas antibody EIA had a specificity of 99.98 percent with negative samples. The sensitivity of the Chagas antibody EIA was 100 percent (80/80) in xenodiagnosed specimens and 100 percent (50/50) in specimens positive by consensus (i.e., reactive in EIA, indirect hemagglutination assay, and immunofluorescence assays). CONCLUSION: This Chagas antibody EIA meets the need for accurate and rapid identification of seroreactive samples in low-prevalence or endemic populations. 相似文献
250.
Simone A Almeida Cibele C Cardoso Laura AA Orellano Adelina M Reis Lucíola S Barcelos Silvia P Andrade 《Clinical and experimental pharmacology & physiology》2014,41(9):691-697
Natriuretic peptide receptor‐C activation by the synthetic ligand C‐ANP‐4–23, a specific agonist for this receptor, has been shown to inhibit key events of the angiogenic cascade, such as migration, proliferation and vascular endothelial growth factor (VEGF) production. In the present study we investigated whether C‐ANP4–23 could also inhibit angiogenesis in the sponge model in vivo. To this end, we evaluated the effects of C‐ANP4–23 on inflammatory and angiogenic components of the fibrovascular tissue induced by polyether polyurethane sponge implants in mice. Measurements of the haemoglobin content (μg/mg wet tissue) and blood flow (laser Doppler perfusion imaging) of the implants, used as an index of vascularization, revealed that single (200 ng) or multiple (200 ng/day, 5 days) doses of C‐ANP4–23 reduced angiogenesis in the implants relative to the phosphate‐buffered saline‐treated group. The peptide exerted an inhibitory effect on nitric oxide production (nitrite levels) and had a dual effect on VEGF levels, depending on the number of doses (i.e. stimulation at 4 days after one dose; inhibition at 7 days after five doses). Histological analysis corroborated the biochemical and functional parameters indicative of inhibition of neovascularization (decreased vessel number) by C‐ANP4–23. The peptide failed to modulate inflammation in our system. The inhibitory effect of C‐ANP4–23 on the angiogenic component of the fibrovascular tissue induced by the synthetic matrix extends the range of the its actions and may indicate its therapeutic potential in controlling angiogenesis in fibroproliferative diseases. 相似文献