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The purpose of this in‐vitro study was to evaluate the influence of the framework design on the durability of inlay‐retained cantilever fixed dental prostheses (IR‐FDPs), made from zirconia ceramic, after artificial ageing. Forty‐eight caries‐free human premolars were prepared as abutments for all‐ceramic cantilevered IR‐FDPs using six framework designs: occlusal–distal (OD) inlay, OD inlay with an oral retainer wing, OD inlay with two retainer wings, mesial–occlusal–distal (MOD) inlay, MOD inlay with an oral retainer ring, and veneer partial coping with a distal box (VB). Zirconia IR‐FDPs were fabricated via computer‐aided design/computer‐aided manufacturing (CAD/CAM) technology. The bonding surfaces were air‐abraded (50 μm alumina/0.1 MPa), and the frameworks were bonded with adhesive resin cement. Specimens were stored for 150 d in a 37°C water bath during which they were thermocycled between 5 and 55°C for 37,500 cycles; thereafter, they were exposed to 600,000 cycles of dynamic loading with a 5‐kg load in a chewing simulator. All surviving specimens were loaded onto the pontic and tested until failure using a universal testing machine. The mean failure load of the groups ranged from 260.8 to 746.7 N. Statistical analysis showed that both MOD groups exhibited significantly higher failure loads compared with the other groups (i.e. the three OD groups and the VB group) and that there was no significant difference in the failure load among the OD groups and the VB group. In conclusion, zirconia IR‐FDPs with a modified design exhibited promising failure modes.  相似文献   
13.
The aim of this study was to investigate the antibacterial resistance of Streptococcus pyogenes (GAS), and correlate the findings with the sales of erythromycin and tetracycline. General practitioners in the Faroe Islands were recruited to send oropharyngeal swabs. From an ongoing pneumococcal study, nasopharyngeal swabs were sampled from healthy children 0–7 years of age. Erythromycin susceptibility data from Iceland were obtained from the reference laboratory at the Landspitali University Hospital. Susceptibility testing in the Faroe Islands and Iceland was performed according to CLSI methods and criteria. The resistance rate to erythromycin and tetracycline found in patients in the Faroe Islands in 2009/2010 was 6% and 30% respectively. Tetracycline resistance in patients declined significantly from 2009 to 2010 (37–10%, p‐value = 0.006 < 0.05) and differed significantly between age groups (p‐value = 0.03 < 0.05). In Iceland, there was a peak in erythromycin resistance in 2008 (44%) and a substantial decrease in 2009 (5%). Although the prevalence of erythromycin and tetracycline resistance in the Faroe Islands and Iceland may be associated with antimicrobial use, sudden changes can occur with the introduction of new resistant clones.  相似文献   
14.
Our aim in this cross-sectional study was to assess the cognitive determinants of Cervical Cancer Screening Behavior (CCSB) among housewife women in Islamabad County, Iran. Through multistage random sampling we recruited and interviewed 280 housewife women. The women who perceived more benefits of performing the Pap test (OR = 1.11), and perceived fewer barriers (OR = 0.915), and higher self-efficacy to perform the test (OR = 1.12) were more likely to have a CCSB in the previous three years. Our findings are informative for the development of targeted interventions to foster CCSB among housewife women.  相似文献   
15.
OBJECTIVES: Previous studies have suggested that the 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors attenuate ischemia-reperfusion injury. We investigated whether pretreatment with simvastatin reduces myocardial infarct size and whether glyburide, a non-selective inhibitor of the ATP-sensitive K channels, abrogates this infarct size-limiting effect. METHODS: Sprague-Dawley rats were treated with either simvastatin (20 mg/kg per day) or saline alone for 3 days. Additional groups of rats were treated as above and on the fourth day they received intravenous glyburide (0.3 mg/kg). All rats underwent 30 min of coronary artery occlusion followed by 180 min of reperfusion. Ischemic myocardium at risk was assessed with blue dye and infarct size with triphenyltetrazolium chloride. RESULTS: Infarct size, expressed as a percentage of the myocardium at risk, was significantly smaller in the simvastatin group (n = 8, 20.8 +/- 3.4%) than in the placebo group (n = 6, 40.1 +/- 2.7%) (P = 0.001). Glyburide abolished the protective effect of simvastatin with infarct size being 34.2 +/- 6.9% and 29.7 +/- 3.9% of the area at risk in the simvastatin group (n = 7) and placebo (n = 7) group, respectively (P = 0.58). CONCLUSIONS: Simvastatin significantly reduced myocardial infarct size. The protective effect was completely abrogated by glyburide, strongly suggesting that this protective effect is mediated via activation of the ATP-sensitive K channels.  相似文献   
16.
17.

Background

The objective of this randomized, double-blind, placebo-controlled study was to evaluate the efficacy of sustained-release methylphenidate (MPH-SR) in treatment of methamphetamine dependence.

Methods

Fifty-six individuals who met DSM-IV-TR criteria for methamphetamine dependence participated in this 10-week trial. The participants were randomly allocated into two groups and received 18 to 54 mg/day sustained-released methylphenidate or placebo for 10 weeks. Craving was evaluated by a visual analogue craving scale every week. Urinary screening test for methamphetamine was carried out each week. The Beck Depression Inventory-II (BDI-II) was used to monitor participant depressive symptoms at baseline and bi-weekly during the treatment period.

Results

At the end of the trial, the MPH-SR group was less methamphetamine positive compared to the placebo group and the difference was significant (p = 0.03). By the end of the study, MPH-SR group showed significantly less craving scores compared to the placebo group [MD (95% CI) = -10.28(0.88-19.18), t(54) = 2.19, p = 0.03]. There was greater improvement in the depressive symptoms scores in the intervention group compared to the placebo group [MD (95% CI) =2.03(0.31-3.75), t (54) =2.37, p = 0.02].

Conclusion

Sustained-released methylphenidate was safe and well tolerated among active methamphetamine users and significantly reduced methamphetamine use, craving and depressive symptoms.

Trial registration

IRCT201202281556N38  相似文献   
18.
Cardiovascular Drugs and Therapy - Abdominal aortic aneurysm (AAA) is a life-threatening condition which, in the absence of increasing diameter or rupture, often remains asymptomatic, and a...  相似文献   
19.
This study was designed to highlight the relation of tumor necrosis factor- (TNF-) to neuropsychiatric lupus (NPLE) manifestations. The relation of TNF- to the type of single photon emission computed tomography (SPECT) findings in this context was also studied. Twenty-one systemic lupus erythematosus (SLE) females, mean age 27.57 ± 9.89 years, and twenty age-matched normal females (controls), were subjected to TNF- assessment. Different clinical and neuropsychiatric manifestations were evaluated. SPECT was carried out for all patients. The results showed that the mean TNF- level (pg/ml) was significantly raised in patients compared with controls (167.8 ± 102.5 versus 64 ± 50.2, respectively, P 0.005). Thirteen patients (69.1%) had NPLE manifestations. NPLE patients had a significantly higher mean TNF- than patients without NPLE (203 ± 102.8 versus 109 ± 47.3, respectively, P 0.03). Positive SPECT findings were found in 18 lupus patients (85.7%), including all 13 patients with NPLE (100% sensitivity), with a multiple focal pattern of hypoperfusion being the most frequent type (9/13), followed by diffuse (3/13), and then single focal pattern (1/13). The mean TNF- was significantly higher in patients with multiple focal pattern (P 0.001). In conclusion, results of this work support the hypothesis that TNF- could be involved in the pathogenesis of NPLE, and hence, it could be speculated that the evolving anti-TNF therapy can play a potential role in the management of this disease.  相似文献   
20.
This case report describes a very rare entity of thrombophilia manifesting as persistent arthritis and digital ulcers. A 9-year-old Egyptian girl presented with a 2-year history of persistent arthritis and digital ulcers. The case was followed up after 4 years. The clinical manifestations and laboratory investigations are recorded. Thrombophilia with partial protein C deficiency appeared to be responsible for the clinical manifestations with underlying ipsilateral osteonecrosis of patella and calcaneum and resorption of the terminal phalanges. Her older sister showed the same picture with additional pulmonary hypertension. In conclusion, arthritis and osteonecrosis appear as a rare presentation of thrombophilia and protein C deficiency, and ignorance of this may lead to misdiagnosis or confusion with other childhood rheumatic diseases.  相似文献   
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