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21.
Clinicopathological correlation of deep retinal vascular anomalous complex in age related macular degeneration 总被引:7,自引:1,他引:6 下载免费PDF全文
Lafaut BA Aisenbrey S Vanden Broecke C Bartz-Schmidt KU 《The British journal of ophthalmology》2000,84(11):1269-1274
AIMS: To analyse the histopathology of "deep retinal vascular anomalous complex" or "chorioretinal anastomosis". METHODS: Six patients with a deep retinal vascular anomalous complex (age range 66-88 years) had fundus photography and fluorescein angiography not more than 14 days before foveal translocation surgery. Four patients were also documented with indocyanine green angiography. The surgical specimens were serially sectioned and stained in a stepped fashion with Masson trichrome, periodic acid Schiff, and phosphotungstic acid haematoxylin, a histochemical stain for fibrin. RESULTS: A subretinal fibrovascular membrane was surrounded by a rim consisting of diffuse drusen (basal laminar deposits), retinal pigment epithelium, and amorphous, fibrinous material interspersed with remains of outer segments in all specimens. In two specimens vascular structures were identified that left the specimen towards the retina. Amorphous material with the remains of outer segments was not found on the retinal side of the fibrovascular tissue itself but in four specimens a small neuroretinal portion (outer nuclear layer) was adherent to the complex. In three specimens a thin fibrocellular membrane was seen at the choroidal side of the diffuse drusen. CONCLUSION: Deep retinal vascular anomalous complex represents histologically neovascularisation growing out of the neuroretina, into the subretinal space, which mimics choroidal neovascularisation. The term therefore appears rightly chosen. 相似文献
22.
Antiviral and antioxidant activity of flavonoids and proanthocyanidins from Crataegus sinaica 总被引:4,自引:0,他引:4
Shahat AA Cos P De Bruyne T Apers S Hammouda FM Ismail SI Azzam S Claeys M Goovaerts E Pieters L Vanden Berghe D Vlietinck AJ 《Planta medica》2002,68(6):539-541
The antiviral and antioxidant activity of some fractions and of a series of flavonoids and proanthocyanidins obtained from Crataegus sinaica (Rosaceae) was evaluated. The O-glycosidic flavonoids and the oligomeric proanthocyanidins exhibited significant inhibitory activity against herpes simplex virus type 1 (HSV-1), which was shown to be due to an extracellular mechanism for procyanidin C-1. Procyanidin C-1 also had the highest antioxidant activity in both the microsomal lipid peroxidation and the hydroxyl radical scavenging assay. In addition to the previously reported phenolic compounds, the pentacyclic triterpenoid ursolic acid (1) and a tetrameric (2) and pentameric procyanidin (3) are reported for the first time. 相似文献
23.
Lefevre J Philippaerts R Delvaux K Thomis M Claessens AL Lysens R Renson R Vanden Eynde B Vanreusel B Beunen G 《International journal of sports medicine》2002,23(Z1):S32-S38
This study investigated the relationship between sports participation/physical activity during youth (13 - 18 years of age) and adulthood (30 - 40 years of age), and cardiovascular risk factors (body fat and fat distribution, blood pressure, lipoprotein levels and cardiorespiratory fitness) at 40 years of age. Subjects were 166 Flemish males from "The Leuven Longitudinal Study on Lifestyle, Fitness and Health". Physical activity was assessed by means of a sports participation inventory and the Tecumseh community Health Study Questionnaire. In addition to correlation and multiple stepwise regression analyses, different groups (at risk, not at risk) were contrasted on sports participation/physical activity parameters using ANOVA. Long-term exposure during adulthood to daily physical activity was slightly related to a low/high risk profile for waist circumference, percent body fatness, triglycerides and peak VO(2). Sports participation during adolescence was not related to levels of cardiovascular risk factors at 40 years of age. 相似文献
24.
Comparison of laparoscopic radical prostatectomy techniques 总被引:1,自引:0,他引:1
Bollens R Roumeguere T Vanden Bossche M Quackels T Zlotta AR Schulman CC 《Current urology reports》2002,3(2):148-151
Over the past years, laparoscopic radical prostatectomy has emerged as an attractive, exciting, and new approach for the surgical treatment of localized prostate cancer. Several centers in Europe and the United States have developed their own technique and have already published their first results. Two main routes have been used, namely, the transperitoneal and extraperitoneal approaches. Data from the literature and available experience demonstrate that this laparoscopic procedure is feasible and teachable and that oncologic and functional results seem comparable to those of classic open radical prostatectomy. Minimal bleeding, reduced blood transfusion rates, shorter hospitalization, and shorter recovery time are unquestionable advantages for laparoscopic procedures. Laparoscopic radical prostatectomy remains a difficult intervention and should be performed in selected centers with experienced teams who already have extensive laparoscopic experience and who recruit enough patients to grant them the proper amount of expertise. This is the only way to achieve excellence in terms of oncologic and functional results. 相似文献
25.
E W Vanden Eijnden E 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(15):8200-8205
The study of passive scalar transport in a turbulent velocity field leads naturally to the notion of generalized flows, which are families of probability distributions on the space of solutions to the associated ordinary differential equations which no longer satisfy the uniqueness theorem for ordinary differential equations. Two most natural regularizations of this problem, namely the regularization via adding small molecular diffusion and the regularization via smoothing out the velocity field, are considered. White-in-time random velocity fields are used as an example to examine the variety of phenomena that take place when the velocity field is not spatially regular. Three different regimes, characterized by their degrees of compressibility, are isolated in the parameter space. In the regime of intermediate compressibility, the two different regularizations give rise to two different scaling behaviors for the structure functions of the passive scalar. Physically, this means that the scaling depends on Prandtl number. In the other two regimes, the two different regularizations give rise to the same generalized flows even though the sense of convergence can be very different. The "one force, one solution" principle is established for the scalar field in the weakly compressible regime, and for the difference of the scalar in the strongly compressible regime, which is the regime of inverse cascade. Existence and uniqueness of an invariant measure are also proved in these regimes when the transport equation is suitably forced. Finally incomplete self similarity in the sense of Barenblatt and Chorin is established. 相似文献
26.
27.
Summary Mouse neonatal brain cell fractions enriched for surface membranes were used as immunogens to produce a heterologous immune serum. Following absorption to remove non-neural anti-mouse activity, this serum demonstrated by microcomplement fixation an anti-brain activity that was completely removed by absorption with neonatal mouse brain or with solid tumors of the mouse transplantable teratoma OTT-6050. Indirect immunofluorescence applied to living monolayer cultures of differentiating teratoma embryoid bodies showed the absorbed serum's reaction with neural cell surfaces only. In material studied with frozen sections, the absorbed serum recognized antigenic sites in all examined areas of both neonatal and adult mouse brain, and only within neuroepithelial cell populations of solid transplants of the teratoma.Supported by research grant CA-11689 from the National Cancer Institute, U.S.P.H.S. S.R.V. is a Scholar of the Insurance Medical Scientist Fund. 相似文献
28.
Effects of preventing reinnervation on axotomized spinal motoneurons in the cat. II. Changes in group Ia synaptic function 总被引:1,自引:0,他引:1
1. Composite excitatory postsynaptic potentials (EPSPs) evoked by electrical stimulation of heteronymous group Ia afferents have been studied at various postoperative times in axotomized motoneurons that were denied the opportunity to reinnervate muscle. 2. The medial gastrocnemius (MG) nerve was transected and sutured onto the surface of the normally innervated lateral gastrocnemius (LG) muscle. The denervated MG muscle was excised thereby eliminating access of regenerating MG motor axons to vacant end-plates. 3. The mean amplitude of monosynaptic Ia EPSPs evoked by electrical stimulation of the LG-soleus (LGS) nerve and recorded in axotomized MG motoneurons showed an initial decline at 20 days postoperative (DPO) that was not significant. At 44 DPO, mean amplitude had declined significantly to 43% of the control mean amplitude. At 90 DPO, mean EPSP amplitude was not significantly different from control. At the latest postoperative time (150-180 DPO), mean amplitude was significantly less than the control amplitude. 4. Mean EPSP rise time (time-to-peak) was significantly increased (27%) at the earliest postoperative times (20-44 DPO). At later postoperative times (90-180), mean EPSP rise time was not significantly different from mean control rise time. 5. "Partial responses" superimposed on EPSPs were not observed at any postoperative time. 6. Mean posttetanic potentiation (PTP) of the LGS EPSP was significantly depressed at 20 DPO. At later postoperative times, PTP did not differ significantly from mean control PTP. 7. The possibility is considered that postaxotomy alterations in the electrical properties of motoneurons may explain these complex variations of mean EPSP amplitude and rise time. 相似文献
29.
Vanden Bogaerde L 《The International journal of periodontics & restorative dentistry》2004,24(3):264-271
A new classification of bone defects adjacent to dental implants is proposed. The classification highlights the importance of defect anatomy in the progression of the regenerative process. Defects were divided into two main groups: (1) closed defects, characterized by the maintenance of intact surrounding bone walls; and (2) open defects, which lack one or more bone walls. The open defect group was then divided into several subgroups that include the majority of situations encountered in clinical practice. The classification could be a useful tool for planning the correct regenerative procedure for each type of defect. 相似文献
30.
Rather easy to perform, pulpotomy of the deciduous teeth is the most frequent endodontic treatment performed on children, but also the most controversial. Based on the amputation of the pulp chamber and the conservation of the inflammation-free root canals, the clinical results can be good, depending on the materials used. In this, calcium hydroxide (Ca(OH)2) as well as zinc-oxide-eugenol (ZOE) have been proven very inflammatory whereas Formocresol (FC) remains the reference even if its clinical toxicity is still reported in literature on a very controversial way. Nevertheless, this was sufficient to trigger and stimulate a search for alternatives, and led to the proposition to use ferric sulfate and even more recently MTA as new bases for the treatment of the pulp stumps after pulp chamber amputation. 相似文献