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91.
Groups of time-courses created from fMRI data by the frequently used correlation analysis are often highly heterogeneous. This heterogeneity is due to the limited selectivity of correlation when trying to match brain time-courses to an externally imposed activation paradigm. Thus, this process unnecessarily generates many type I errors (false positives). Furthermore, as a consequence of the heterogeneity, time-courses identified and grouped by correlation may in fact describe different activations. After demonstrating this inadequacy, we give one particular approach to partition such a heterogeneous group into internally more homogeneous subgroups, using Kendall's coefficient of concordance W, and show its applicability and application to both simulated and in vivo data. Such group partition and "purification" will help subsequent inferential methods to deal more efficiently with false positives. 相似文献
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93.
Samuel G.A. Wood Nilanjan Chakraborty Martin W. Smith Mark J. Summers Stuart A. Brewer 《Journal of occupational and environmental hygiene》2019,16(1):41-53
Steady-state axisymmetric simulations using the Reynolds-Averaged Navier-Stokes equations have been carried out in order to optimize the performance of a Chemical, Biological, Radiological, and Nuclear (CBRN) canister filter for its use in a powered air-purifying respirator (PAPR). Alterations have been made to the shape of the canister, the spacing of the rear wall of the canister with regard to the carbon filter, and the bracketing between (i) the particulate filter and the carbon bed and (ii) the carbon bed and the canister wall. The pressure drops across the canister and the residence time distribution at the rear of the carbon bed have been analyzed in detail based on an extensive parametric analysis involving the aforementioned variations. It has been demonstrated that the non-uniform porosity profile of the carbon bed resulted in alternating regions of high and low velocity close to the canister wall, providing a possible route for breakthrough. Designs, which included a bracket at the rear of the carbon bed, blocked this route and consequently had a longer minimum mean residence time than those, which did not. It has also been shown that the spacing between the carbon bed and the canister rear wall had a large impact on both residence time and pressure drop. In cases where the carbon backed directly onto the canister rear wall flow in the axial direction from the outside wall toward the canister axis resulted in far greater pressure drop and a reduction in minimum mean residence time within the carbon bed. 相似文献
94.
Geraldine M. Leydon Beth Stuart Rachael H. Summers Paul Little Stuart Ekberg Fiona Stevenson Carolyn A. Chew-Graham Lucy Brindle John Heritage Paul Drew Michael V. Moore 《Patient education and counseling》2018,101(8):1394-1402
Objectives
To establish: a) feasibility of training GPs in a communication intervention to solicit additional patient concerns early in the consultation, using specific lexical formulations (“do you have ‘any’ vs. ‘some’ other concerns?”) noting the impact on consultation length, and b) whether patients attend with multiple concerns and whether they voiced them in the consultation.Methods
A mixed-methods three arm RCT feasibility study to assess the feasibility of the communication intervention.Results
Intervention fidelity was high. GPs can be trained to solicit additional concerns early in the consultation (once patients have presented their first concern). Whilst feasible the particular lexical variation of ‘any’ vs ‘some’ seemed to have no bearing on the number of patient concerns elicited, on consultation length or on patient satisfaction. The level of missing questionnaire data was low, suggesting patients found completion of questionnaires acceptable.Conclusion
GPs can solicit for additional concerns without increasing consultation length, but the particular wording, specifically ‘any’ vs. ‘some’ may not be as important as the placement of the GP solicitation.Practice implications
GPs can solicit early for additional concerns and GPs can establish patients’ additional concerns in the opening of the consultation, which can help to plan and prioritise patients multiple concerns. 相似文献95.
96.
Peter J. Donovick Zelig S. Dolinsky Valerie P. Perdue Richard G. Burright Brian Summers Raymond H. Cypess 《Brain research bulletin》1981,7(3)
Ingestion of palatable and unpalatable solutions was measured in adult mice to which had been administered the common parasite of the dog, Toxocara canis alone, or in combination with lead. In addition, response to hot plate and susceptibility to electroconvulsive seizure were also measured. Results from the palatability test indicated that either lead or Toxocara may alter the mouse's mode of interacting with its environment. However, the two agents in combination interacted in their effects on consummatory behavior. Results from the hot plate and ECS measures were less clear with respect to how lead and/or Toxocara influence temperature reactivity and seizure susceptibility. Histological examination of the CNS in parasite infected animals revealed Wallerian Type degeneration of fiber pathways including the corpus callosum, olfactory tract, and cerebellar penduncles. 相似文献
97.
98.
Blood donation leads to a decrease in natural killer cell activity: a study in normal blood donors and cancer patients 总被引:2,自引:0,他引:2
Transfusion-induced immunosuppression has long been known to be beneficial for organ transplantation patients, but recent retrospective studies suggest that blood transfusions may be detrimental for patients with cancer. If autologous blood is used to avoid immunosuppression, the assumption is that the procedure, involving blood donation, is immunologically neutral. In the present study, this assumption was evaluated by monitoring 33 normal blood donors and 16 colorectal cancer patients before and after donation of 1 (500 mL) and 2 units of blood, respectively. The cancer patients belonged to the autologous arm of a randomized trial in which the effects of allogeneic versus autologous blood on cancer prognosis were studied. The patients donated 2 units of blood with an interval of 3 to 4 days between donations. Flow cytometric analysis revealed that blood donation by normal donors and cancer patients had no effect on the proportion of B, T, and natural killer (NK) cells. Only the total number of lymphocytes was significantly decreased in the normal donors on Day 12 after donation. Blood donation had no significant effect on T-cell function assessed by phytohemagglutinin stimulation in normal donors or in cancer patients donating 2 units of blood. A significant depression of NK cell function (88% and 74% of predonation levels) was observed in normal donors on Days 2 and 5 after donation; on Day 12, the activity was again normal. Colorectal cancer patients had a significantly depressed NK cell activity (54% of predonation activity) on Day 12 after the first donation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
99.
Effect of percutaneous transluminal coronary angioplasty on arrhythmias complicating angina. 下载免费PDF全文
Four patients who had stenosis of a single major coronary artery which was treated by percutaneous transluminal coronary angioplasty are described. Three had exercise induced myocardial ischaemia complicated by ventricular tachycardia, fibrillation, and sinus bradycardia, respectively. Asystole developed in a fourth patient who had spontaneous chest pain. After successful percutaneous transluminal coronary angioplasty these arrhythmias did not recur spontaneously or on treadmill exercise testing. Percutaneous coronary angioplasty can be effective in preventing arrhythmias complicating acute myocardial ischaemia secondary to stenosis of a single major coronary artery. 相似文献
100.