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981.
Information published in this department is based on releases from the manufacturers of the products described. The manufacturers' literature accompanying the products should be consulted for complete details concerning dosage and administration, precautions, contraindications, and possible side effects. 相似文献
982.
Neil Love 《Postgraduate medicine》2013,125(8):125-138
In all medical situations, it is important to know what you are dealing with. Prompt recognition of the problem is especially crucial in patients who may have undiscovered cancer or a recurrence. The best therapy not only controls the underlying tumor but also arrests complications. Dr Love uses two illustrative case reports to describe frequently seen complications of cancer, their clinical presentations, and methods to confirm the diagnosis. 相似文献
983.
Shannon M. Thyne Joshua P. Rising Vicki Legion Mary Beth Love 《The Journal of asthma》2013,50(9):667-673
Pediatric asthma programs have struggled to integrate children's medical and social needs. We developed and piloted an integrated team model for asthma care for low-income children through the Yes We Can Urban Asthma Partnership. Program evaluation demonstrated increases in prescribing controller medications (p <0.05), use of action plans (p<0.001), and the use of mattress covers (p<0.001); and decrease in asthma symptoms (p<0.01). Additional changes occurred within the local system of asthma care to support ongoing efforts to improve asthma management. We conclude that pediatric asthma programs can effectively target the social and medical needs of children in a sustainable manner. 相似文献
984.
985.
986.
987.
Esaú P Santos Danielle RR Cavalcante Allan UC Melo José C Pereira Margarete Z Gomes Ricardo LC Albuquerque Jr 《Head & face medicine》2011,7(1):1-6
Extracorporeal formation of mineralized bone-like tissue is still an unsolved challenge in tissue engineering. Embryonic stem cells may open up new therapeutic options for the future and should be an interesting model for the analysis of fetal organogenesis. Here we describe a technique for culturing embryonic stem cells (ESCs) in the absence of artificial scaffolds which generated mineralized miromasses. Embryonic stem cells were harvested and osteogenic differentiation was stimulated by the addition of dexamethasone, ascorbic acid, and ß-glycerolphosphate (DAG). After three days of cultivation microspheres were formed. These spherical three-dimensional cell units showed a peripheral zone consisting of densely packed cell layers surrounded by minerals that were embedded in the extracellular matrix. Alizarine red staining confirmed evidence of mineralization after 10 days of DAG stimulation in the stimulated but not in the control group. Transmission electron microscopy demonstrated scorching crystallites and collagenous fibrils as early indication of bone formation. These extracellular structures resembled hydroxyl apatite-like crystals as demonstrated by distinct diffraction patterns using electron diffraction analysis. The micromass culture technique is an appropriate model to form three-dimensional bone-like micro-units without the need for an underlying scaffold. Further studies will have to show whether the technique is applicable also to pluripotent stem cells of different origin. 相似文献
988.
989.
Platelets interact with fibrin only after activation 总被引:5,自引:2,他引:5
Interactions between platelets and fibrin have been visualized by phase contrast, epifluorescence, and scanning electron microscope examination of clots formed with dansylcadaverine-labeled fibrin and gel-filtered platelets. After thrombin activation, the platelets appeared as fluorescent aggregates with bridging strands of fibrin; formaldehyde- fixed platelets were not fluorescent under the same experimental conditions. Scanning electron micrographs demonstrated that thrombin- activated cells had numerous pseudopods to which the fibrin strands adhered; fixed platelets exhibited a smooth discoid appearance and did not interact with the clot. Platelets trapped in clots formed with Batroxobin (Pentapharm) (platelets are not activated by Batroxobin as confirmed by light-scattering aggregometry measurements) remained as nonfluorescent, discoid cells, whereas platelets first activated by adenosine diphosphate formed brightly fluorescent aggregates. Light- scattering data of thrombin activation (0.2 U/mL) indicated that preincubation of platelets with 0.1 mmol/L prostaglandin E1 (PGE1) prior to addition of thrombin decreased the extent and rate of platelet shape change and resulted in 100-fold slower aggregation. Clots formed in the presence of PGE1 revealed decreased fluorescence intensity and fewer platelet-fibrin contacts. Gly-Pro-Arg-Pro, which blocks fibrinogen binding and fibrin assembly, was also effective in blocking platelet-fibrin interactions. These results indicate that platelet activation is a prerequisite for attachment of platelets to fibrin. 相似文献
990.
Love BA Collins KK Walsh EP Triedman JK 《Journal of cardiovascular electrophysiology》2001,12(1):17-25
INTRODUCTION: The electrophysiologic mechanism of intra-atrial reentrant tachycardia (IART) is generally thought to be a macroreentrant circuit revolving around a nonconductive or highly anisotropic barrier. However, the electrical and anatomic substrate that supports these circuits has been incompletely defined. Our objectives were to characterize the atria of patients with IART using electroanatomic mapping in sinus or atrially paced rhythm and to determine whether electrical barriers identified in sinus/atrially paced rhythm are associated with IART circuits. METHODS AND RESULTS: Eighteen patients with IART and a remote history of repaired or palliated congenital heart disease were studied [8 biventricular repair, 8 single ventricle palliation (7 Fontan), and 2 Mustard repair]. Thirteen patients had a right AV valve. In sinus/atrially paced rhythm, electrical evidence of a crista terminalis was identified in 11 patients, an atriotomy in 12, and > or = 1 right atrial free-wall scar in 11. In 26 IART circuits characterized, 12 used the right AV valve as a central obstacle, 6 used a right atrial free-wall scar, 3 used an atriotomy, 3 used the crista terminalis, and 2 circuits used an atrial septal scar. All central obstacles used by IART circuits were identified in sinus/atrially paced rhythm. CONCLUSION: The crista terminalis, atriotomy, and right atrial scars can be identified in patients with repaired congenital heart disease by electroanatomic mapping in sinus/atrially paced rhythm. These conduction barriers frequently function as the central obstacle for IART. Demonstration of such features may help focus investigational mapping without reliance on spontaneous initiation of the tachycardia. 相似文献