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Within health science programs there has been a call for more faculty development, particularly for teaching and learning. The primary objectives of this review were to describe the current landscape for faculty development programs for teaching and learning and make recommendations for the implementation of new faculty development programs. A thorough search of the pertinent health science databases was conducted, including the Education Resource Information Center (ERIC), MEDLINE, and EMBASE, and faculty development books and relevant information found were reviewed in order to provide recommendations for best practices. Faculty development for teaching and learning comes in a variety of forms, from individuals charged to initiate activities to committees and centers. Faculty development has been effective in improving faculty perceptions on the value of teaching, increasing motivation and enthusiasm for teaching, increasing knowledge and behaviors, and disseminating skills. Several models exist that can be implemented to support faculty teaching development. Institutions need to make informed decisions about which plan could be most successfully implemented in their college or school.  相似文献   
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Objective. To assess the impact of awarding partial credit to team assessments on team performance and on quality of team interactions using an answer-until-correct method compared to traditional methods of grading (multiple-choice, full-credit).Methods. Subjects were students from 3 different offerings of an ambulatory care elective course, taught using team-based learning. The control group (full-credit) consisted of those enrolled in the course when traditional methods of assessment were used (2 course offerings). The intervention group consisted of those enrolled in the course when answer-until-correct method was used for team assessments (1 course offering). Study outcomes included student performance on individual and team readiness assurance tests (iRATs and tRATs), individual and team final examinations, and student assessment of quality of team interactions using the Team Performance Scale.Results. Eighty-four students enrolled in the courses were included in the analysis (full-credit, n=54; answer-until-correct, n=30). Students who used traditional methods of assessment performed better on iRATs (full-credit mean 88.7 (5.9), answer-until-correct mean 82.8 (10.7), p<0.001). Students who used answer-until-correct method of assessment performed better on the team final examination (full-credit mean 45.8 (1.5), answer-until-correct 47.8 (1.4), p<0.001). There was no significant difference in performance on tRATs and the individual final examination. Students who used the answer-until-correct method had higher quality of team interaction ratings (full-credit 97.1 (9.1), answer-until-correct 103.0 (7.8), p=0.004).Conclusion. Answer-until-correct assessment method compared to traditional, full-credit methods resulted in significantly lower scores for iRATs, similar scores on tRATs and individual final examinations, improved scores on team final examinations, and improved perceptions of the quality of team interactions.  相似文献   
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Evans  EA; Mohandas  N 《Blood》1987,70(5):1443-1449
Micropipette aspiration tests on single erythrocytes have previously shown that the static rigidity (membrane shear modulus) of oxygenated sickle cells increased with increasing hemoglobin concentration, whereas the rigidity of normal cells was independent of hemoglobin concentration. Moreover, it was observed that after mechanical extension, sickle cells exhibited persistent deformation more frequently and to a greater extent than normal cells. To ascertain if differences in association of normal and sickle hemoglobin with the membrane could account for these observations, we measured rheologic properties of normal membranes reconstituted with sickle hemoglobin and sickle membranes reconstituted with normal hemoglobin. The static rigidity of normal ghosts reloaded with sickle hemoglobin was higher than those of either normal ghosts reloaded with normal hemoglobin or native normal cells. On the other hand, the increased rigidity of native sickle cells decreased to near-normal values following reconstitution with normal hemoglobin. Furthermore, we observed that normal ghosts reconstituted with sickle hemoglobin exhibited persistent bumps after mechanical extension, but no bumps formed on normal ghosts reconstituted with normal hemoglobin. Moreover residual bumps were not produced on sickle cells reloaded with normal hemoglobin. Since mechanical characteristics peculiar to sickle cells could be induced in normal cells by incorporation of sickle hemoglobin, and since normal characteristics could be restored to sickle cells by incorporation of normal hemoglobin, we suggest that the interaction of sickle hemoglobin with the cell membrane is responsible for augmented static rigidity of oxygenated sickle erythrocytes.  相似文献   
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Ranheim  EA; Cantwell  MJ; Kipps  TJ 《Blood》1995,85(12):3556-3565
Crosslinking the CD27 antigen on T cells provides a costimulatory signal that, in concert with T-cell receptor crosslinking, can induce T- cell proliferation and cellular immune activation. We find that chronic lymphocytic leukemia (CLL) B cells from most patients coexpress both membrane-bound and soluble CD27, along with its newly identified ligand, CD70. The expression of soluble CD27 may preclude leukemic B cells from stimulating T cells via CD70, thereby potentially impairing their ability to function as effective antigen-presenting cells. We find that leukemic B-cell expression of soluble and membrane-bound CD27 can be downmodulated through a CD40-dependent signal. This signal also induces enhanced expression of CD70 on both normal and leukemic B cells. We find that tumor necrosis factor (TNF)-alpha, or the Th1 cytokine interferon (IFN)-gamma, also can induce downmodulation of CD27, whereas Th2-associated cytokines interleukin-4 (IL-4) or IL-10 can enhance leukemic B-cell expression of this accessory molecule. The modulation of CD27 induced by these conditions is accompanied by reciprocal changes in the expression levels of CD70, suggesting that these accessory molecules may be engaged in reciprocal receptor-ligand downmodulation. Consistent with this, we observe that co-culture of CLL B cells with transfected murine plasmacytoma cells that express human CD70 affects downmodulation of CD27 and enhanced expression of CD70 on leukemic B cells, but does not affect expression of CD27 mRNA. However, we find that CD40-crosslinking, in addition to reducing the level of CD27 protein, also reduces leukemic B-cell expression of CD27 mRNA. This argues that the changes in the expression levels of CD27 following CD40-signaling are not simply due to induced increases in the expression levels of CD70. Finally, we demonstrate that reciprocal changes in expression of CD27 and CD70 may contribute to the enhanced antigen-presenting capacity of CLL B cells after CD40-dependent leukemic B-cell activation. These findings expand the understanding of the regulation of costimulatory molecules important in antigen presentation and also have implications for the immunobiology of and therapy for CLL.  相似文献   
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In subjects without coronary disease, coronary perfusion pressure generated with closed-chest cardiopulmonary resuscitation (CPR) bears a direct relationship to myocardial blood flow. The effect of coronary lesions on this relationship was studied in an experimental porcine model not requiring thoracotomy. Coronary stenoses (a 50% reduction in coronary cross-sectional area) or total coronary occlusions were created by percutaneous, transarterial catheter placement of a Teflon cylinder in the left anterior descending artery of 21 swine (30 to 60 kg). Coronary perfusion pressure, defined as the aortic diastolic pressure minus right atrial diastolic pressure, was correlated with myocardial blood flow measured with nonradioactive, colored microspheres during external chest compression CPR. Complete occlusion of the left anterior coronary artery resulted in essentially no CPR-generated blood flow to the anterior myocardium distal to the site of occlusion. Coronary perfusion pressure showed a positive correlation with myocardial blood flow above the area of occlusion (r = 0.783; p less than 0.01) but did not correlate with myocardial blood flow below the occlusion site (r = 0.239). In the presence of a patent coronary artery stenosis, coronary perfusion pressure correlated with myocardial blood flow both above (r = 0.841; p less than 0.001) and below (r = 0.508; p less than 0.05) the stenosis. During closed-chest CPR producing coronary perfusion pressures between 30 and 60 mm Hg, anterior myocardial blood flow was 109 +/- 16 ml/min/100 gm above a patent stenosis and 66 +/- 13 ml/min/100 gm below the stenosis (p less than 0.005). Over a wide range of coronary perfusion pressures, myocardial blood flow below a coronary lesion was significantly less than that above the lesion. Coronary occlusions and stenoses can substantially affect the amount of CPR-generated coronary perfusion pressure needed to produce distal myocardial blood flow.  相似文献   
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