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991.
Mario Gössl Jörg Herrmann Hui Tang Daniele Versari Offer Galili Dallit Mannheim S. Vincent Rajkumar Lilach O. Lerman Amir Lerman 《Basic research in cardiology》2009,104(6):695-706
Vasa vasorum (VV) neovascularization is a key feature of early atherosclerosis and adds substantial endothelial exchange-surface
to the coronary vessel wall. Thus, it is conceivable that VV neovascularization favors the entry of pro-inflammatory and pro-atherosclerotic
blood components into the coronary vessel wall. We sought to investigate the effects of Thalidomide (Th), a potent anti-angiogenic
drug on vasa vasorum (VV) neovascularization, vessel wall inflammation, and neointima formation in early experimental atherosclerosis.
Female domestic swine, 3 months old, were fed normal (N, n = 12) or high-cholesterol diet (HC, n = 12) for 3 months. In each group six pigs were randomized to 200 mg Thalidomide daily for the diet period (N + Th, HC + Th).
LADs were scanned with micro-CT (20 μm cubic voxel size) to determine VV spatial density (#/mm2). Fresh-frozen coronary tissue
was used for western blotting (VEGF, TNF-α, LOX-1, Iκβα and Gro-α) and electrophoretic mobility shift assay (EMSA, NFκβ).
Treatment with Thalidomide preserved VV spatial density [2.7 ± 0.3 (N), 6.4 ± 0.7 (HC), 3.5 ± 0.8 (HC + Th); p = ns HC + Th vs. N] and inhibited the expression of VEGF, TNF-α and LOX-1, but not NFκβ activity in the coronary vessel wall.
Immunofluorescence analyses revealed co-localization of vWF but not SMA and NFκβ, TNF-α as well as VEGF in HC and HC + Th
coronaries. Intima-media thickness was significantly inhibited in HC + Th compared to HC. Serum levels of hs-CRP and TNF-α
did not differ among the groups. Our study supports a role of VV neovascularization in the development of and a therapeutic
potential for anti-angiogenic intervention in early atherosclerosis. 相似文献
992.
Julien Tripette Tamas Alexy Marie-Dominique Hardy-Dessources Daniele Mougenel Eric Beltan Tawfik Chalabi Roger Chout Maryse Etienne-Julan Olivier Hue Herbert J. Meiselman Philippe Connes 《Haematologica》2009,94(8):1060-1065
Background
Recent evidence suggests that red blood cell aggregation and the ratio of hematocrit to blood viscosity (HVR), an index of the oxygen transport potential of blood, might considerably modulate blood flow dynamics in the microcirculation. It thus seems likely that these factors could play a role in sickle cell disease.Design and Methods
We compared red blood cell aggregation characteristics, blood viscosity and HVR at different shear rates between sickle cell anemia and sickle cell hemoglobin C disease (SCC) patients, sickle cell trait carriers (AS) and control individuals (AA).Results
Blood viscosity determined at high shear rate was lower in sickle cell anemia (n=21) than in AA (n=52), AS (n=33) or SCC (n=21), and was markedly increased in both SCC and AS. Despite differences in blood viscosity, both sickle cell anemia and SCC had similar low HVR values compared to both AA and AS. Sickle cell anemia (n=21) and SCC (n=19) subjects had a lower red blood cell aggregation index and longer time for red blood cell aggregates formation than AA (n=16) and AS (n=15), and a 2 to 3 fold greater shear rate required to disperse red blood cell aggregates.Conclusions
The low HVR levels found in sickle cell anemia and SCC indicates a comparable low oxygen transport potential of blood in both genotypes. Red blood cell aggregation properties are likely to be involved in the pathophysiology of sickle cell disease: the increased shear forces needed to disperse red blood cell aggregates may disturb blood flow, especially at the microcirculatory level, since red blood cell are only able to pass through narrow capillaries as single cells rather than as aggregates. 相似文献993.
994.
Brunetti ND Amodio G De Gennaro L Dellegrottaglie G Pellegrino PL Di Biase M Antonelli G 《Journal of thrombosis and thrombolysis》2009,28(1):23-30
Aim To assess feasibility and reliability of telecardiology technologies applied to a region-wide public emergency health-care
service. Methods About 27,841 patients from all over Apulia (19.362 km2, 4 million inhabitants) were referred from October 2004 until April 2006 to public emergency health-care number “118” and
underwent ECG evaluation according to a previously fixed inclusion protocol. Data recorded were transmitted with mobile telephone
support to a telecardiology “hub” active 24-h a day. Hospitalization or further examinations were arranged by emergency physicians
on the basis of ECG diagnosis and consultation. Results Thirty-nine percent of patients complained of chest pain (CP) or epigastric pain, 26% loss of consciousness, 10% breathlessness,
and 7% palpitations. Atrial fibrillation (AF) was diagnosed in 11.68% of patients and ST-elevation acute myocardial infarction
(STEMI) in 1.91%. Among patients with CP, ECG showed STEMI in only 3.84% of cases, theoretically eligible for fibrinolysis
or primary PCI; patients with STEMI complained of CP in 78.94% of cases. Of the patients, 65.28% with STEMI were from small
towns without coronary care units, thus benefiting from an immediate pre-hospital diagnosis. Among patients with palpitations,
only 10.27% of subjects showed ECG signs of supra-ventricular tachycardia and 25.18% of AF; other subjects avoided further
improper hospitalization or emergency department monitoring. Conclusions This first region-wide leading experience shows the feasibility and reliability of telecardiology applied to a public emergency
health-care service. Telemedicine protocols would probably be useful in lowering the number of improper hospitalizations and
shortening delay in the diagnosis process of some heart diseases. 相似文献
995.
996.
Role of the basolateral nucleus of the amygdala in endocannabinoid-mediated stress-induced analgesia
Recent work in our laboratories has demonstrated that an opioid-independent form of stress-induced analgesia (SIA) is mediated by endogenous ligands for cannabinoid receptors-anandamide and 2-arachidonoylglycerol (2-AG) [A.G. Hohmann, R.L. Suplita, N.M. Bolton, M.H. Neely, D. Fegley, R. Mangieri, J.F. Krey, J.M. Walker, P.V. Holmes, J.D. Crystal, A. Duranti, A. Tontini, M. Mor, G. Tarzia, D. Piomelli, An endocannabinoid mechanism for stress-induced analgesia, Nature 435 (2005) 1108-1112]. The present study was conducted to examine the contribution of cannabinoid CB1 receptors in the basolateral nucleus of the amygdala (BLA) and central nucleus of the amygdala (CeA) to nonopioid SIA. SIA was induced by continuous footshock (3 min 0.9 mA) and quantified behaviorally using the tail-flick test. Microinjection of the CB1 antagonist/inverse agonist rimonabant (SR141716A) into the BLA, a limbic forebrain region with high densities of CB1 receptors, suppressed SIA relative to control conditions. By contrast, the same dose administered into the CeA, where CB1 immunoreactivity is largely absent, or outside the amygdala did not alter SIA. To examine the contribution of endocannabinoids in the BLA to SIA, we used selective pharmacological inhibitors of the anandamide-degrading enzyme fatty-acid amide hydrolase (FAAH) and the 2-arachidonoylglycerol-degrading enzyme monoacylglycerol lipase (MGL). The FAAH inhibitor URB597 and MGL inhibitor URB602, at doses that enhanced SIA following microinjection in the midbrain periaqueductal gray, did not alter SIA relative to control conditions. Our findings suggest that CB1 receptors in the BLA but not the CeA contribute to SIA, but pharmacological inhibition of endocannabinoid degradation at these sites does not affect the expression of stress antinociception. 相似文献
997.
Electrical stimulation of the cerebellar cortex by implanted electrodes has been shown to ameliorate refractory epilepsy. We investigated the potential therapeutic role of high-frequency cerebellar rTMS in patients affected by refractory epilepsy due to single or multiple foci. Six patients, three with single and three with multiple epileptic foci, underwent 20 rTMS sessions. Each session was given daily, excluding weekends, and consisted of two trains of 50 stimuli (5 Hz frequency and 90% motor threshold intensity), separated by 50s interval. rTMS was delivered through a focal coil (2 cm below and lateral to the inion) bilaterally in patients with multiple foci (two trains for hemisphere: 100 stimuli each side) and contralaterally to the epileptic focus in the others. Seizure frequency was monitored four weeks before stimulation (pre-rTMS), during the four-week treatment (rTMS) and four weeks after the treatment (post-rTMS). The rTMS over the cerebellar cortex was associated with a significant decrease of rTMS versus pre-rTMS seizure frequency both in patients with single and multiple epileptic foci. However, during the post-rTMS period seizure frequency was back to the pre-rTMS frequency. Although the results are still preliminary, they encourage further studies on larger series of patients. In particular, this rTMS approach, as compared with others, might be more useful in patients with multiple epileptic foci. 相似文献
998.
Hepatocyte growth factor effects on mesenchymal stem cells: proliferation, migration, and differentiation 总被引:22,自引:0,他引:22
Forte G Minieri M Cossa P Antenucci D Sala M Gnocchi V Fiaccavento R Carotenuto F De Vito P Baldini PM Prat M Di Nardo P 《Stem cells (Dayton, Ohio)》2006,24(1):23-33
Hepatocyte growth factor (HGF), a pleiotropic cytokine of mesenchymal origin promoting migration, proliferation, and survival in a wide spectrum of cells, can also modulate different biological responses in stem cells, but the mechanisms involved are not completely understood so far. In this context, we show that short-term exposure of mesenchymal stem cells (MSCs) to HGF can induce the activation of its cognate Met receptor and the downstream effectors ERK1/2, p38MAPK, and PI3K/Akt, while long-term exposure to HGF resulted in cytoskeletal rearrangement, cell migration, and marked inhibition of proliferation through the arrest in the G1-S checkpoint. When added to MSCs, the K252A tyrosine kinase inhibitor prevented HGF-induced responses. HGF's effect on MSC proliferation was reversed by p38 inhibitor SB203580, while the effects on cell migration were abrogated by PI3K inhibitor Wortmannin, suggesting that HGF acts through different pathways to determine its complex effects on MSCs. Prolonged treatment with HGF induced the expression of cardiac-specific markers (GATA-4, MEF2C, TEF1, desmin, alpha-MHC, beta-MHC, and nestin) with the concomitant loss of the stem cell markers nucleostemin, c-kit, and CD105. 相似文献
999.
Cardaropoli D Re S Manuzzi W Gaveglio L Cardaropoli G 《The International journal of periodontics & restorative dentistry》2006,26(6):553-559
The aim of the present study was to evaluate whether it is possible to orthodontically move migrated teeth into infrabony defects augmented with a biomaterial. Three adult patients suffering from chronic periodontitis were treated. Each of the patients presented with an infrabony defect adjacent to a migrated maxillary central incisor. After cause-related therapy was completed, a surgical procedure was performed using the papilla preservation technique. The defects were filled with a collagen bovine bone mineral; after 2 weeks, an orthodontic device was activated using light, continuous forces. Orthodontic treatment time varied from 4 to 9 months; during this period, patients were enrolled in an oral hygiene recall program. At baseline and 6 months after the end of therapy, probing pocket depths (PPD) and clinical attachment levels (CAL) were assessed. In addition, the vertical and horizontal dimensions of the defects were measured on standardized radiographs. Residual mean PPD was 3.33 mm, with a mean reduction of 3.67 mm. Mean CAL gain was 4.67 mm. Radiologic vertical and horizontal bone fills were, on average, 3.17 mm and 2.0 mm, respectively. The present case series shows the effectiveness of a combined periodontic-orthodontic approach for the treatment of infrabony defects. Reduction of PPD to physiologic values, CAL gain, and radiologic defect resolution were obtained. No detrimental effects from the orthodontic movement were observed on the augmentation material. 相似文献
1000.