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931.
ObjectivesTo evaluate and compare the intensity of pain caused by rapid maxillary expansion (RME) with two expanders: Hyrax and Haas type, in growing patients.Materials and MethodsThirty-nine patients (23 girls and 16 boys) with an average age of 9.3 years (SD = 1.39 years) were randomized into two groups and treated with Hyrax- and Haas-type expanders. In both groups, initial activation of the expander screw was one full turn on the first day followed by 2/4 of a turn two times a day (morning and night) for 7 days. Inclusion criteria were patients presenting with a posterior crossbite or maxillary atresia between 7 and 12 years old. To evaluate the intensity of pain during the active phase of the treatment, a combination of the Numerical Rating Scale and Wong-Baker Faces Pain Scale was used. Mann-Whitney test was used to compare the two treatment groups.ResultsThere was significant inverse correlation between days following insertion and pain. During the expansion period, 100% of the children reported some pain. Hyrax expander subjects reported greater pain than those treated with the Haas-type expander only on the first day. The level of pain remained greater in girls throughout treatment.ConclusionsPain was reported regardless of the type of expander and was higher in the Hyrax group only on the first day of activation.  相似文献   
932.
Streptococcus agalactiae is a common agent of clinical and subclinical bovine mastitis and an important cause of human infections, mainly among pregnant women, neonates and nonpregnant adults with underlying diseases. The present study describes the genetic and phenotypic diversity among 392 S. agalactiae human and bovine strains isolated between 1980 and 2006 in Brazil. The most prevalent serotypes were Ia, II, III and V and all the strains were susceptible to penicillin, vancomycin and levofloxacin. Resistance to clindamycin, chloramphenicol, erythromycin, rifampicin and tetracycline was observed. Among the erythromycin resistant strains, mefA/E, ermA and, mainly, ermB gene were detected, and a shift of prevalence from the macrolide resistance phenotype to the macrolide-lincosamide-streptogramin B resistance phenotype over the years was observed. The 23 macrolide-resistant strains showed 19 different pulsed-field gel electrophoresis profiles. Regarding macrolide resistance, a major concern in S. agalactiae epidemiology, the present study describes an increase in erythromycin resistance from the 80s to the 90s followed by a decrease in the 2000–2006 period. Also, the genetic heterogeneity described points out that erythromycin resistance in Brazil is rather due to horizontal gene transmission than to spreading of specific macrolide-resistant clones.  相似文献   
933.

Background

The epidemiological characteristics of thoracic aortic diseases (TAD) in the State of São Paulo and in Brazil, as well as their impact on the survival of these patients have yet to be analyzed.

Objectives

To evaluate the mortality impact of TAD and characterize it epidemiologically.

Methods

Retrospective analysis of data from the public health system for the TAD registry codes of hospitalizations, procedures and deaths, from the International Code of Diseases (ICD-10), registered at the Ministry of Health of São Paulo State from January 1998 to December 2007.

Results

They were 9.465 TAD deaths, 5.500 men (58.1%) and 3.965 women (41.9%); 6.721 dissections (71%) and 2.744. aneurysms. In 86.3% of cases the diagnosis was attained during autopsy. There were 6.109 hospitalizations, of which 67.9% were males; 21.2% of them died (69% men), with similar proportions of dissection and aneurysm between sexes, respectively 54% and 46%, but with different mortality. Men with TAD die more often than women (OR = 1.5). The age distribution for deaths and hospitalizations was similar with predominance in the 6th decade. They were 3.572 surgeries (58% of hospitalizations) with 20.3% mortality (patients kept in clinical treatment showed 22.6% mortality; p = 0.047). The number of hospitalizations, surgeries, deaths of in-patients and general deaths by TAD were progressively greater than the increase in population over time.

Conclusions

Specific actions for the early identification of these patients, as well as the viability of their care should be implemented to reduce the apparent progressive mortality from TAD seen among our population.  相似文献   
934.

Background

The impact of intravascular ultrasound (IVUS) use on stenting has shown inconclusive results.

Objective

Systematic review and meta-analysis of the impact of IVUS on stenting regarding the clinical and angiographic evolution.

Methods

A search was performed in Medline/Pubmed, CENTRAL, Embase, Lilacs, Scopus and Web of Science databases. It included randomized clinical trials (RCTs) that evaluated the implantation of stents guided by IVUS, compared with those using angiography alone (ANGIO). The minimum follow-up duration was six months and the following outcomes were assessed: thrombosis, mortality, myocardial infarction, percutaneous and surgical revascularization, major adverse cardiovascular events (MACE) and restenosis. The binary outcomes were presented considering the number of events in each group; the estimates were generated by a random effects model, considering Mantel-Haenszel statistics as weighting agent and magnitude of effect for the relative risk (RR) with its respective 95% confidence interval (95%CI). Higgins I2 test was used to quantify the consistency between the results of each study.

Results

A total of 2,689 articles were evaluated, including 8 RCTs. There was a 27% reduction in angiographic restenosis (RR: 0.73, 95% CI: 0.54-0.97, I2 = 51%) and statistically significant reduction in the rates of percutaneous revascularization and overall (RR: 0.88; 95% CI: 0.51 to 1.53, I2 = 61%, RR: 0.73, 95% CI: 0.54 to 0.99, I2 = 55%), with no statistical difference in surgical revascularization (RR: 0.95, 95% CI: 0.52-1.74, I2 = 0%) in favor of IVUS vs. ANGIO. There were no differences regarding the other outcomes in the comparison between the two strategies.

Conclusion

Angioplasty with stenting guided by IVUS decreases the rates of restenosis and revascularization, with no impact on MACE, acute myocardial infarction, mortality or thrombosis outcomes.  相似文献   
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939.
While surgical resection has remained the mainstay of treatment in early-stage renal cell carcinoma (RCC), therapeutic options in the advanced setting have remarkably expanded over the last 20 years. Tyrosine kinase inhibitors targeting the vascular endothelial growth factor receptor (VEGF-TKIs) and anti-programmed cell death 1 (PD-1)/anti-programmed death-ligand 1 (PD-L1)-based immune checkpoint inhibitors (ICIs) have become globally accepted options in the upfront metastatic setting, with different ICI-based combination strategies improving overall survival compared to single-agent Sunitinib. Although some patients benefit from long-term responses, most eventually develop disease progression. Ongoing efforts to better understand the biology of RCC and the different mechanisms of acquired resistance have led to the identification of promising therapeutic targets. Belzutifan, a novel agent targeting the angiogenic pathway involving hypoxia-inducible factors (HIFs), has already been approved for the treatment of early-stage tumors associated with VHL disease and represents a very promising therapy in advanced RCC. Other putative targets include epigenetic regulation enzymes, as well as several metabolites such as adenosine, glutaminase and tryptophan, which are critical players in cancer cell metabolism and in the tumor microenvironment. Different methods of immune regulation are also being investigated, including CAR-T cell therapy and modulation of the gut microbiome, in addition to novel agents targeting the interleukin-2 (IL-2) pathway. This review aims to highlight the emergent novel therapies for RCC and their respective completed and ongoing clinical trials.  相似文献   
940.
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