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991.
ObjectiveActivated platelets release serotonin, causing platelet aggregation and vasoconstriction. Serotonin levels were investigated in patients with acute coronary syndrome (ACS) and chronic stable angina (CSA) treated with percutaneous coronary intervention (PCI).MethodsConsecutive patients undergoing PCI for either ACS or CSA were enrolled between July 2009 and April 2010. Patients were pre-treated with dual antiplatelet agents (aspirin and clopidogrel) before PCI. Serum serotonin levels, measured at baseline, pre- and post-PCI, and at 90 min, and 6, 12, 24 and 48 h following PCI, were compared between ACS and CSA groups.ResultsSixty-three patients with ACS and 60 with CSA were included. Overall baseline characteristics were similar between the two groups. Serotonin levels at post-PCI (55.2 ± 120.0 versus 20.1 ± 24.0) and at peak (regardless of timepoint; 94.0 ± 170.9 versus 38.8 ± 72.3) were significantly higher in the ACS versus CSA group. At 90 min and 6, 24 and 48 h post-PCI, serum serotonin was numerically, but not significantly, higher in patients with ACS. Serotonin levels fluctuated in both groups, showing an initial rise and fall, rebound at 24 h and drop at 48 h post-PCI.ConclusionsIn patients undergoing PCI, serum serotonin was more elevated in patients with ACS than those with CSA, suggesting the need for more potent and sustained platelet inhibition, particularly in patients with ACS.  相似文献   
992.
The estimation of needle deflection when the needle interacts with biological tissue is challenging in needle steering. Most previous studies have used homogeneous tissue models to estimate the deflection of a needle. However, biological tissue typically has a layered structure with variable mechanical properties and geometric features. In this study, we propose a needle deflection model with a double-layered elastic medium. Each layer possesses distinct mechanical properties, which result in inconsistent degrees of friction force on the needle surface, needle-cutting force, and forces caused by the stiffness of the elastic medium. The model uses the Rayleigh–Ritz method to analytically estimate the needle deflection. To validate the model, needle steering experiments were performed using double-layered tissue phantoms and porcine tissues. The experimental results revealed that changes in reaction force at the needle base occurred when the needle passed through the boundary between the two layers. The mean absolute error between the estimated and measured needle tip trajectory was 0.88 ± 0.30 mm for the double-layered tissue phantom and 1.85 ± 0.73 mm for the porcine tissue. These results are comparable with previous studies of homogeneous tissue. The proposed model could improve needle steering in biological tissues, which consist of multiple layers.  相似文献   
993.
Implantation of a foreign material almost certainly results in the formation of a fibrous capsule around the implant however, mechanistic events leading to its formation are largely unexplored. Mast cells are an inflammatory cell type known to play a role in the response to material implants, through the release of pro-inflammatory proteases and cytokines from their α-granules following activation. This study examined the in vivo and in vitro response of mast cells to chitosan, through detection of markers known to be produced by mast cells or involved with the inflammatory response. Mast cells, identified as Leder stained positive cells, were shown to be present in response to material implants. Additionally, the mast cell receptor, c-kit, along with collagen, serglycin, perlecan and chondroitin sulphate were detected within the fibrous capsules, where distribution varied between material implants. In conjunction, rat mast cells (RBL-2H3) were shown to be activated following exposure to chitosan as indicated by the release of β-hexosaminidase. Proteoglycan and glycosaminoglycans produced by the cells showed similar expression and localisation when in contact with chitosan to when chemically activated. These data support the role that mast cells play in the inflammatory host response to chitosan implants, where mediators released from their α-granules impact on the formation of a fibrous capsule by supporting the production and organisation of collagen fibres.  相似文献   
994.
995.
Previous studies have identified an association between depressive mood and marijuana use. We examined adolescent self-control as a predictor of membership in joint developmental trajectories of depressive mood and marijuana use from adolescence to young adulthood. Urban African Americans and Puerto Ricans (N = 838) were sampled when participants were on average 14, 19, 24, and 29 years old. Using growth mixture modeling, four joint trajectory groups of depressive mood and marijuana use were established: low marijuana use/low depressive mood, low marijuana use/intermediate depressive mood, high marijuana use/low depressive mood, and high marijuana use/high depressive mood. Weighted logistic regression analysis showed that self-control at age 14 distinguished the high marijuana use/high depressive mood group and the low marijuana use/low depressive mood group from each of the other groups. Findings show that the co-occurrence of high levels of marijuana use and depressive mood from adolescence into young adulthood is predicted by low levels of self-control in adolescence. On the other hand, high selfcontrol is associated with low marijuana use and low levels of depression over time. Thus, while deficits in self-control in adolescence constitute a significant risk for maladjustment over time, high self-control exerts a protective factor with regard to marijuana use and depressive mood into young adulthood.  相似文献   
996.
The etiology of benign paroxysmal positional vertigo (BPPV) is still elusive even though detached otolith particles from the utricular macula are generally thought to be responsible for the pathogenesis of BPPV. Sudden sensorineural hearing loss (SSNHL), of which the etiology is also idiopathic in most cases, may accompany concurrent BPPV. This uncommon condition of concurrent BPPV with SSNHL has been assumptively explained as selective damage of the cochlea and the utricle due to viral neurolabyrinthitis. Recently, radiological evidences that inner ear hemorrhage is observed in patients with SSNHL accompanied by severe vertigo have been reported. The basic hypothesis for this study is that blood debris in the endolymphatic fluid due to inner ear hemorrhage is one of the causes of concurrent posterior semicircular canal (PSCC) BPPV in patient with ipsilateral SSNHL. In this report, we will outline the clinical findings of 4 patients with PSCC BPPV with SSNHL, and present an experimental results using whole blood in artificial endolymph to evaluate the hypothesis.  相似文献   
997.
We studied the pathogenesis and transmissibility of a novel avian-origin H7N9 influenza virus in pigs. When pigs were infected with H7N9 influenza virus, they did not show any clear clinical signs (such as sneezing, fever and loss of body weight), and they shed viruses through their noses for 2 days after infection. No transmission occurred between infected and naïve pigs. Pigs suffered from mild pneumonia, which was accompanied by the induction of inflammatory cytokines and chemokines such as IL-8 and CCL1. Taken together, our results suggest that pigs may not play an active role in transmitting H7N9 influenza virus to mammals.  相似文献   
998.

Purpose

It is a widely accepted premise in the scientific community and by athletes alike, that adding resistance exercise to a regular regimen of endurance training increases endurance performance in endurance-trained men. However, critical power (CP), capillarization, and myofiber size remain unaffected by this addition. Therefore, we tested whether the superimposition of resistance exercise with whole-body vibration and vascular occlusion (vibroX) would improve these variables in endurance-trained males relative to resistance exercise alone.

Methods

Twenty-one young, endurance-trained males were randomly assigned either to a vibroX (n = 11) or resistance (n = 10) training group. Both groups trained in a progressive mode twice a week for 8 weeks. Pre and post training, histochemical muscle characteristics, thigh muscle size, endurance and strength parameters were determined.

Results

vibroX increased CP (P = 0.001), overall capillary-to-fiber ratio (P = 0.001) and thigh lean mass (P < 0.001), while these parameters were unaffected by resistance training. The gain in CP by vibroX was positively correlated with the gain in capillarization (R 2 = 0.605, P = 0.008), and the gain in thigh lean mass was paralleled by increases in MyHC-1 and MyHC-2 fiber cross-sectional areas and strength. Maximum voluntary torque and the finite work capacity above CP (W′) increased significantly only following resistance training.

Conclusions

We achieved a proof of concept by demonstrating that modification of resistance exercise by superimposing side-alternating whole-body vibration and sustained vascular occlusion induced further improvements in CP, capillarization and hypertrophy, all of which were not observed with resistance training alone.  相似文献   
999.

Background

Increasing numbers of reports show the beneficial effects of listening to Mozart music in decreasing epileptiform discharges as well as seizure frequency in epileptic children. There has been no effective method to reduce seizure recurrence after the first unprovoked seizure until now. In this study, we investigated the effect of listening to Mozart K.448 in reducing the seizure recurrence rate in children with first unprovoked seizures.

Methods

Forty-eight children who experienced their first unprovoked seizure with epileptiform discharges were included in the study. They were randomly placed into treatment (n?=?24) and control (n?=?24) groups. Children in the treatment group listened to Mozart K.448 daily before bedtime for at least six months. Two patients in the treatment group were excluded from analysis due to discontinuation intervention. Finally, forty-six patients were analyzed. Most of these patients (89.1%) were idiopathic in etiology. Seizure recurrence rates and reduction of epileptiform discharges were compared.

Results

The average follow-up durations in the treatment and control groups were 18.6?±?6.6 and 20.1?±?5.1 months, respectively. The seizure recurrence rate was estimated to be significantly lower in the treatment group than the control group over 24 months (37.2% vs. 76.8%, p?=?0.0109). Significant decreases in epileptiform discharges were also observed after 1, 2, and 6 months of listening to Mozart K.448 when compared with EEGs before listening to music. There were no significant differences in gender, mentality, seizure type, and etiology between the recurrence and non-recurrence groups.

Conclusions

Although the case number was limited and control music was not performed in this study, the study revealed that listening to Mozart K.448 reduced the seizure recurrence rate and epileptiform discharges in children with first unprovoked seizures, especially of idiopathic etiology. We believe that Mozart K.448 could be a promising alternative treatment in patients with first unprovoked seizures and abnormal EEGs. Further large-scaled study should be conducted to confirm the effect.

Trial registration

NCT01892605, date: June-19-2013  相似文献   
1000.
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