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91.
92.
93.
The aim of our study is to investigate whether single-nucleotide dystrophin gene (DMD) variants associate with variability in cognitive functions in healthy populations. The study included 1240 participants from the Erasmus Rucphen family (ERF) study and 1464 individuals from the Rotterdam Study (RS). The participants whose exomes were sequenced and who were assessed for various cognitive traits were included in the analysis. To determine the association between DMD variants and cognitive ability, linear (mixed) modeling with adjustment for age, sex and education was used. Moreover, Sequence Kernel Association Test (SKAT) was used to test the overall association of the rare genetic variants present in the DMD with cognitive traits. Although no DMD variant surpassed the prespecified significance threshold (P<1 × 10−4), rs147546024:A>G showed strong association (β=1.786, P-value=2.56 × 10−4) with block-design test in the ERF study, while another variant rs1800273:G>A showed suggestive association (β=−0.465, P-value=0.002) with Mini-Mental State Examination test in the RS. Both variants are highly conserved, although rs147546024:A>G is an intronic variant, whereas rs1800273:G>A is a missense variant in the DMD which has a predicted damaging effect on the protein. Further gene-based analysis of DMD revealed suggestive association (P-values=0.087 and 0.074) with general cognitive ability in both cohorts. In conclusion, both single variant and gene-based analyses suggest the existence of variants in the DMD which may affect cognitive functioning in the general populations.  相似文献   
94.

Objective

To assess the effect of race on the incidence of aortic stenosis (AS) and utilization and outcomes of aortic valve replacement (AVR).

Patients and Methods

Patients older than 60 years hospitalized with a primary diagnosis of AS and those who underwent AVR between 2003 and 2014 were included. Adjusted and unadjusted incidence of AS-related hospitalizations, utilization rates of AVR, in-hospital morbidity and mortality, and resource utilization was compared between whites and African Americans (AAs).

Results

Between January 1, 2003, and December 31, 2014, the incidence of AS-related admissions increased from 13 (95% CI, 12.8-13.2) to 26 (95% CI, 25.7-26.4) cases per 100,000 patient-years in whites and from 3 (95% CI, 3.5-3.8) to 9.5 (95% CI, 9.4-9.8) cases per 100,000 patient-years in AAs (P<.001). The incidence density ratio decreased from 4.3 (95% CI, 2.27-6.6) in 2003 to 2.7 (95% CI, 1.1-3.8) in 2014. The ratio of AVR to AS-related admissions was 11.3% in whites and 6.7% in AAs (P<.001). Crude in-hospital mortality after AVR was higher in AAs (6.4% vs 4.7%; P<.001). However, after propensity score matching, in-hospital morality after isolated AVR was not significantly different between AAs and whites (4.7% vs 3.7%; P=.12). African Americans also had longer hospitalizations (12±12 days vs 10±9 days; P<.001), higher rates of nonhome discharge (32.1% vs 27.2%; P=.004), and higher cost of hospitalization ($55,631±$37,773 vs $52,521±$38,040; P<.001).

Conclusions

African Americans undergo AVR less than whites. The underlying etiology of this disparity is multifactorial, but may be related to a lower incidence of AS in AAs. Aortic valve replacement is associated with similar risk-adjusted in-hospital mortality but higher cost and longer hospitalizations in AAs than in whites.  相似文献   
95.

Objective

To review the literature and assess the comparative effectiveness of ultrasound-guided versus landmark-guided local corticosteroid injections in patients with carpal tunnel syndrome (CTS).

Data Sources

Cochrane Central Register of Controlled Trials, MEDLINE (PubMed), Embase (Ovid), and Web of Science (from inception to February 1, 2017).

Study Selection

Randomized controlled trials (RCTs) comparing ultrasound-guided injection with landmark-guided injection in patients with CTS were included.

Data Extraction

Two authors independently screened abstracts and full texts. The outcomes of interest were Symptom Severity Scale (SSS) and Functional Status Scale (FSS) scores of the Boston Carpal Tunnel Questionnaire and 4 electrodiagnostic parameters, including compound muscle action potential (CMAP), sensory nerve action potential (SNAP), distal motor latency (DML), and distal sensory latency (DSL).

Data Synthesis

Overall, 569 abstracts were retrieved and checked for eligibility; finally, 3 RCTs were included (181 injected hands). Pooled analysis showed that ultrasound-guided injection was more effective in SSS improvement (mean difference [MD], ?.46; 95% confidence interval [CI], ?.59 to ?.32; P<.00001), whereas no significant difference was observed between the 2 methods in terms of the FSS (MD, ?.25; 95% CI, ?.56 to .05; P=.10). There were also no statistically significant differences in improvements of CMAP (MD, 1.54; 95% CI, 0.01 to 3.07; P=.05), SNAP (MD, ?0.02; 95% CI, ?6.27 to 6.23; P>.99), DML (MD, .05; 95% CI, ?.30 to .39; P=.80), or DSL (MD, .00; 95% CI, ?.65 to .65; P>.99).

Conclusions

This review suggested that ultrasound-guided injection was more effective than landmark-guided injection in symptom severity improvement in patients with CTS; however, no significant differences were observed in functional status or electrodiagnostic improvements between the 2 methods.  相似文献   
96.

Background

The placement of a central venous catheter for the administration of vasopressors is still recommended and required by many institutions because of concern about complications associated with peripheral administration of vasopressors.

Objective

Our aim was to determine the incidence of complications from the administration of vasopressors through peripheral venous catheters (PVC) in patients with circulatory shock, and to identify the factors associated with these complications.

Methods

This was a prospective, observational study conducted in the emergency department (ED) of a tertiary care medical center. Patients presenting to the ED with circulatory shock and in whom a vasopressor was started through a PVC were included. Research fellows examined the i.v. access site for complications twice daily during the period of peripheral vasopressor administration, then daily up to 48 h after treatment discontinuation or until the patient expired.

Results

Of the 55 patients that were recruited, 3 (5.45% overall, 6% of patients receiving norepinephrine) developed complications; none were major. Two developed local extravasation and one developed local thrombophlebitis. All three complications occurred during the vasopressor infusion, none in the 48 h after discontinuation, and none required any medical or surgical intervention. Two of the three complications occurred in the hand, and all occurred in patients receiving norepinephrine and with 20-gauge catheters.

Conclusions

The incidence of complications from the administration of vasopressors through a PVC is small and did not result in significant morbidity in this study. Larger prospective studies are needed to better determine the factors that are associated with these complications, and identify patients in whom this practice is safe.  相似文献   
97.

Background

Lingual hematoma (LH) is a relatively uncommon entity seen after both medical and traumatic etiologies. Regardless of the cause, the feared complication is acute airway obstruction.

Case Report

Our case involves a 39-year-old man who presented to the Emergency Department via emergency medical services with an enlarging LH after an unwitnessed fall, suspected to be an alcohol withdrawal seizure. The bleeding was likely exacerbated by previously undiagnosed thrombocytopenia. Airway stabilization was rapidly established via nasotracheal intubation after standard intubation techniques were deemed unfeasible. Despite correction of the coagulopathy, the LH continued to expand, resulting in bilateral tympanomandibular joint (TMJ) dislocations. To our knowledge, this complication has not been previously reported as a complication of LH.

Why Should an Emergency Physician Be Aware of This?

Despite being a relatively uncommon condition, LH has the potential to result in life-threatening airway obstruction with limited airway options. Prompt airway stabilization should be the first priority upon diagnosis. A rapidly evolving LH can limit standard orotracheal rapid sequence intubation options, and may require alternative airway procedures. Additionally, ongoing lingual swelling after airway stabilization has now been shown in our case to result in bilateral TMJ dislocations. Concurrent management of reversible coagulopathy may help prevent this complication or reduce its severity.  相似文献   
98.

Background and Purpose

Interstitial lung disease accounts for a group of chronic and progressive disorders associated with severe pulmonary vascular remodelling, peripheral vascular rarefaction and fibrosis, thus limiting lung function. We have previously shown that Akt is necessary for myofibroblast differentiation, a critical event in organ fibrosis. However, the contributory role of the Akt-mTOR pathway in interstitial lung disease and the therapeutic benefits of targeting Akt and mTOR remain unclear.

Experimental Approach

We investigated the role of the Akt-mTOR pathway and its downstream molecular mechanisms in chronic hypoxia- and TGFβ-induced pulmonary vascular pruning and fibrosis in mice. We also determined the therapeutic benefits of the Akt inhibitor triciribine and the mTOR inhibitor rapamycin for the treatment of pulmonary fibrosis in mice.

Key Results

Akt1/ mice were protected from chronic hypoxia-induced peripheral vascular pruning. In contrast, hyperactivation of Akt1 induced focal fibrosis similar to TGFβ-induced fibrosis. Pharmacological inhibition of Akt, but not the Akt substrate mTOR, inhibited hypoxia- and TGFβ-induced pulmonary vascular rarefaction and fibrosis. Mechanistically, we found that Akt1 modulates pulmonary remodelling via regulation of thrombospondin1 (TSP1) expression. Hypoxic Akt1/ mice lungs expressed less TSP1. Moreover, TSP1/ mice were resistant to adMyrAkt1-induced pulmonary fibrosis.

Conclusions and Implications

Our study identified Akt1 as a novel target for the treatment of interstitial lung disease and provides preclinical data on the potential benefits of the Akt inhibitor triciribine for the treatment of interstitial lung disease.  相似文献   
99.
The electrochemical and corrosion (uniform and localized) behavior of a binary Ni52Ti48 shape memory alloy (SMA) and two ternary Ni52Ti48−xCox (x = 1.5 and 4.0 wt%) SMAs were studied. Measurements were conducted in 0.9% NaCl solution at 37 °C employing various electrochemical methods. These include: linear polarization resistance (LPR), linear sweep voltammetry (LSV), chronoamperometry and dynamic electrochemical impedance spectroscopy (DEIS). Such measurements were complemented with scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) analysis. Results revealed that the addition of alloyed Co to NiTi significantly reduced the uniform corrosion rate of the studied SMA and greatly enhanced its pitting corrosion resistance. XPS measurements evidenced high stability of the passive layer and limited adsorption of chloride ions. Additionally, it was found that the passive layer remained primarily composed of titanium oxides. Microstructure changes accompanying the addition of Co were also used to account for its role in improving the corrosion resistance of these materials.

The electrochemical and corrosion (uniform and localized) behavior of a binary Ni52Ti48 shape memory alloy (SMA) and two ternary Ni52Ti48−xCox (x = 1.5 and 4.0 wt%) SMAs were studied.  相似文献   
100.
In this study, a composite material, manganese oxide/reduced titania nanotubes (Mn2O3/R-TNTs), was synthesized through incorporation of Mn2O3 onto R-TNTs via the reverse pulse electrodeposition technique. The influence of pulse reverse duty cycles on the morphological, structural and electrochemical performance of the surface was studied by varying the applied duty cycle from 10% to 90% for 5 min total on-time at an alternate potential of −0.90 V (Eon) and 0.00 V (Eoff). FESEM analysis revealed the uniform deposition of Mn2O3 on the circumference of the nanotubes. The amount of Mn2O3 loaded onto the R-TNTs increased as a higher duty cycle was applied. Cyclic voltammetry and galvanostatic charge–discharge tests were employed to elucidate the electrochemical properties of all the synthesized samples in 1 M KCl. The specific capacitance per unit area was greatly enhanced upon the incorporation of Mn2O3 onto R-TNTs, but showed a decrease as a high duty cycle was applied. This proved that low amounts of Mn2O3 loading enhanced the facilitation of the active ions for charge storage purposes. The optimized sample, Mn2O3/R-TNTs synthesized at 10% duty cycle, exhibited high specific capacitance of 18.32 mF cm−2 at a current density of 0.1 mA cm−2 obtained from constant current charge–discharge measurements. This revealed that the specific capacitance possessed by Mn2O3/R-TNTs synthesized at 10% duty cycle was 6 times higher than bare R-TNTs.

Mn2O3 was coated onto reduced titania nanotubes by reverse pulse electrodeposition, showing smooth and homogenous deposits without covering the opening of the nanotubes.  相似文献   
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