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71.

Introduction  

Exhaled breath condensate (EBC) analysis is a promising method for investigating airway pathology. In this pilot study we tested the cytokine pattern of EBC of lung transplant patients with and without clinical evidence of bronchiolitis obliterans syndrome (BOS).  相似文献   
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73.
Percutaneous coronary intervention (PCI) for chronic total occlusions (CTOs) has been rapidly evolving during recent years. With improvement in equipment and techniques, high success rates can be achieved at experienced centers, although overall success rates remain low. Prospective, randomized-controlled data regarding optimal use and indications for CTO PCI remain limited. CTO PCI should be performed when the anticipated benefit exceeds the potential risk. New high-quality studies of the clinical outcomes and techniques of CTO PCI are needed, as is the expansion of expert centers and operators that can achieve excellent clinical outcomes in this challenging patient and lesion subgroup. In the current review the authors summarize the latest publications in CTO PCI and provide an overview of the current state of the field.  相似文献   
74.
Little is known about the metabolic or cardiovascular effects of selective ER modulators (SERMs), such as raloxifene hydrochloride (RLX), in postmenopausal women with type 2 diabetes mellitus (DM). Therefore, the effect of RLX vs. placebo (PL) on glycemic control, insulin sensitivity, as well as effects on a number of hormone, lipid, coagulation, and safety factors were determined in 30 postmenopausal women with type 2 DM in a randomized, double blind, cross-over trial. All participants had a SHBG serum concentration below 60 nmol/liter at baseline and had stable diabetes controlled by either oral hypoglycemic agents or diet for 1 month. In the first treatment period, participants received 12 wk of either PL or RLX, followed by an 8-wk washout before the second treatment period. In the second treatment period, participants were crossed over to the other treatment. Compared with PL, RLX did not significantly affect fasting blood glucose, hemoglobin A(1c), lipids, fasting insulin, or insulin sensitivity (as measured by the euglycemic clamp technique). Compared with PL, RLX reduced fibrinogen levels by 0.77 g/liter (P < 0.001), IGF-I by 2.4 nmol/liter (P < 0.001), and free T by 0.73 pmol/liter (P = 0.038) and increased SHBG by 5.5 nmol/liter (P = 0.001) and IGF-binding protein-3 by 0.57 ng/ml (P = 0.007). Our results demonstrate that RLX does not significantly affect glycemic control and has favorable or neutral effects on selected surrogate markers of cardiovascular risk in postmenopausal women with type 2 diabetes mellitus while decreasing hyperandrogenicity in these patients.  相似文献   
75.
Activation of endothelial nitric oxide synthase (eNOS) in portal hypertensive (PHT) gastric mucosa leads to hyperdynamic circulation and increased susceptibility to injury. However, the signaling mechanisms for eNOS activation in PHT gastric mucosa and the role of TNF-alpha in this signaling remain unknown. In PHT gastric mucosa we studied (1) eNOS phosphorylation (at serine 1177) required for its activation; (2) association of the phosphatidylinositol 3-kinase (PI 3-kinase), and its downstream effector Akt, with eNOS; and, (3) whether TNF-alpha neutralization affects eNOS phosphorylation and PI 3-kinase-Akt activation. To determine human relevance, we used human microvascular endothelial cells to examine directly whether TNF-alpha stimulates eNOS phosphorylation via PI 3-kinase. PHT gastric mucosa has significantly increased (1) eNOS phosphorylation at serine 1177 by 90% (P <.01); (2) membrane translocation (P <.05) and phosphorylation (P <.05) of p85 (regulatory subunit of PI 3-kinase) by 61% and 85%, respectively; (3) phosphorylation (P <.01) and activity (P <.01) of Akt by 40% and 52%, respectively; and (4) binding of Akt to eNOS by as much as 410% (P <.001). Neutralizing anti-TNF-alpha antibody significantly reduced p85 phosphorylation, phosphorylation and activity of Akt, and eNOS phosphorylation in PHT gastric mucosa to normal levels. Furthermore, TNF-alpha stimulated eNOS phosphorylation in human microvascular endothelial cells. In conclusion, these findings show that in PHT gastric mucosa, TNF-alpha stimulates eNOS phosphorylation at serine 1177 (required for its activation) via the PI 3-kinase-Akt signal transduction pathway.  相似文献   
76.
Mutations in the myotubularin (MTM)-related protein 2 (MTMR2) gene are responsible for the severe autosomal recessive neuropathy Charcot-Marie-Tooth disease type 4B1. MTMR2 belongs to the MTM family of dual-specific phosphatases that use phosphatidylinositol (PI) 3,5-bisphosphate [PI(3,5)P2] and PI 3-phosphate [PI(3)P] as their substrate. Because these substrates are localized in the membrane bilayer, membrane targeting of Mtmr2 is an important regulatory mechanism. In hypoosmotically stressed COS cells with increased levels of PI(3,5)P2, Mtmr2 is bound to the membrane of vacuoles formed under these conditions. Using several mutant forms of Mtmr2, we identified two domains that are necessary for membrane association: (i) A pleckstrin homology-GRAM domain; and (ii) a coiled-coil module. Protein-lipid overlay assays show that the pleckstrin homology-GRAM domain binds to PI(3,5)P2 and PI(5)P, a substrate and a product of the Mtmr2 enzyme, respectively. We also demonstrate that Mtmr2 forms a dimer and that the C-terminal coiled-coil is responsible for homodimerization, in addition to membrane association. Our data indicate that phosphoinositide-protein interactions, as well as protein-protein interactions, are necessary for the correct regulation of MTMR2.  相似文献   
77.
Pioglitazone, a thiazolidinedione, improves glycemic control primarily by increasing peripheral insulin sensitivity in patients with type 2 diabetes, whereas metformin, a biguanide, exerts its effect primarily by decreasing hepatic glucose output. In the first head-to-head, double-blind clinical trial comparing these two oral antihyperglycemic medications (OAMs), we studied the effect of 32-wk monotherapy on glycemic control and insulin sensitivity in 205 patients with recently diagnosed type 2 diabetes who were naive to OAM therapy. Subjects were randomized to either 30 mg pioglitazone or 850 mg metformin daily with titrations upward to 45 mg (77% of pioglitazone patients) and 2550 mg (73% of metformin patients), as indicated, to achieve fasting plasma glucose levels of less than 7.0 mmol/liter (126 mg/dl). Pioglitazone was comparable to metformin in improving glycemic control as measured by hemoglobin A1C and fasting plasma glucose. At endpoint, pioglitazone was significantly more effective than metformin in improving indicators of insulin sensitivity, as determined by reduction of fasting serum insulin (P = 0.003) and by analysis of homeostasis model assessment for insulin sensitivity (HOMA-S; P = 0.002). Both OAM therapies were well tolerated. Therefore, pioglitazone and metformin are equally efficacious in regard to glycemic control, but they exert significantly different effects on insulin sensitivity due to differing mechanisms of action. The more pronounced improvement in indicators of insulin sensitivity by pioglitazone, as compared with metformin monotherapy in patients recently diagnosed with type 2 diabetes who are OAM-naive, may be of interest for further clinical evaluation.  相似文献   
78.
Introduction:Multimodality assessment of coronary artery lesions has demonstrated superior effectiveness compared to the conventional approach, for assessing both anatomical and functional significance of a coronary stenosis. Multiple imaging modalities can be integrated into a fusion imaging tool to better assess myocardial ischemia.Material and methods:The FUSE-HEART trial is a single center, prospective, cohort study that will assess the impact of a coronary artery stenosis on myocardial function and viability, based on advanced fusion imaging technics derived from Cardiac Computed Tomography Angiography (CCTA). Moreover, the study will investigate the correlation between morphology and composition of the coronary plaques and myocardial ischemia in the territory irrigated by the same coronary artery. At the same time, imaging parameters will be correlated with inflammatory status of the subjects. The trial will include 100 subjects with coronary lesions found on CCTA examination. The study population will be divided into 2 groups: first group will consist of subjects with anatomically significant coronary lesions on native coronary arteries and the second one will include subjects surviving an acute myocardial infarction. The vulnerability score of the subjects will be calculated based on presence of CCTA vulnerability markers of the coronary plaques: napkin ring sign, positive remodeling, spotty calcifications, necrotic core, and low-density plaques. 3D fusion images of the coronary tree will be generated, integrating the images reflecting wall motion with the ones of coronary circulation. The fusion models will establish the correspondence between plaque composition and wall motion in the subtended myocardium of the coronary artery. The study primary outcome will be represented by the rate of major adverse cardiac events related to myocardial ischemia at 1-year post assessment, in correlation with the degree of coronary artery stenosis and myocardial ischemia or viability.The secondary outcomes are represented by the rate of re-hospitalization, rate of survival and rate of major adverse cardiovascular events (including cardiovascular death or stroke), in correlation with the morphology and composition of atheromatous plaques located in a coronary artery, and myocardial ischemia in the territory irrigated by the same coronary artery.Conclusion:In conclusion, FUSE-HEART will be a study based on modern imaging tools that will investigate the impact of a coronary artery stenosis on myocardial function and viability, using advanced fusion imaging technics derived from CCTA, sighting to validate plaque composition and morphology, together with inflammatory biomarkers, as predictors to myocardial viability.  相似文献   
79.
Carotenoids loaded in nanoparticles should be regarded as a promising way to increase the availability in healthy cells and to induce apoptosis in cancer. Lutein is a carotenoid that, in contrast to beta-carotene, has no known toxicities. Oral cancer represents one of the most frequent types of cancer world-wide with an incidence rate of about 9% of all types of cancer. Almost 95% of all oral cancers are represented by squamous cell carcinomas (OSCC). The aim of this study was to review and analyse the effects of lutein and Poly(d,l-lactide-co-glycolide) (PLGA) Nps containing lutein (Lut Nps) on oxidative stress biomarkers (OXSR-1, FOXO-3, TAC) and collagen degradation biomarker–MMP-9, in human cells BICR10 of buccal mucosa squamous carcinoma. Lut Nps were prepared by the emulsion-solvent evaporation method. MMP, OXSR-1, TAC, FOXO-3 and MMP-9 were measured in tumour cell lysates by the ELISA technique. Our results have shown that in Lut 100 cells and Lut Nps the OXSR1 (p < 0.001, p < 0.001) and TAC (p < 0.001, p < 0.001) values were significantly higher than in control cells. The Lut 100 and Lut Nps FOXO-3 levels revealed no significant differences versus the control. MMP-9 levels were significantly reduced (p < 0.001) in the Lut Nps cells versus control cells. In our study conditions, lutein and lutein Nps did not trigger an oxidative stress by ROS induction. However, lutein Nps treatment seemed to have a positive effect, by downregulating the MMP-9 levels. Loaded in Nps, lutein could be regarded as a protective factor against local invasiveness, in whose molecular landscape MMPs, and especially MMP-9 are the main actors.  相似文献   
80.
Background and purposePercutaneous coronary intervention (PCI) via radial approach has been shown to be an alternative to femoral approach in emergency cases; however, its feasibility has been questioned. This single-center study was performed to compare the outcomes and complication rates between transradial (TR) and transfemoral (TF) PCI in ST-segment-elevation myocardial infarction (STEMI).Methods and materialsThe clinical and angiographic data of 582 consecutive STEMI patients treated with PCI between 2001 and 2006 were evaluated in a retrospective study. Forty-three patients were excluded from the present study due to cardiogenic shock or rescue PCI. Patients (n=539) were categorized into the TR group (n=167) or the TF group (n=372), and several parameters were evaluated to assess the advantages and drawbacks of TR access: access-site crossover, rate of access-site complications, procedure time, fluoroscopy time, X-ray area dose, major adverse cardiac events (MACE) at 1 month, and consumption of angioplasty equipment.ResultsIn the TR group, the crossover rate to femoral access was 5%, while in the TF group, it was 0.8% (P<.05). There was a significant difference, in both major and minor access-site complications, between the TR group and the TF group (0% vs. 5%, P<.05, and 4% vs. 9%, P<.05, respectively). Consumption of angioplasty equipment proved to be the same for the two groups. The MACE rate was 4% in the TR group and 11% in the TF group (P<.05).ConclusionsOur results suggest that the TR approach is a safe and effective way to treat STEMI; furthermore, site-related complications are less common with this approach.  相似文献   
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