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51.
Pulmonary lymphangiectasia revisited   总被引:1,自引:0,他引:1  
PURPOSE: Pulmonary lymphangiectasia (PL) is a rare, poorly documented disease characterized by abnormal pulmonary lymphatics. Although case reports are published, little is known about survivors past the neonatal period. METHODS: This is a retrospective review of histologically proven PL in fetuses, infants, and long term survivors since 1965. RESULTS: Eleven children (8 boys, 3 girls) and 8 aborted fetuses (7 male, 1 female) were identified. The fetuses weighed 463.4 g (177 to 681 g). Six were aborted between 19 to 24 weeks of gestation for multiple malformations or anencephaly, and 2 spontaneously aborted: one with PL only, the other with twin-twin transfusion syndrome. Clinical PL was diagnosed between 0 and 11 months of age. Six children died (2 neonatal, 4 within 10 days), 5 survived. Two deaths occurred after cardiac surgery. Among survivors, the symptomatology and frequency of admissions diminished over time. Symptoms included progressive respiratory distress, chronic cough, recurrent pneumonia, bronchial asthma, and choking. One child with bilateral chylothorax was later diagnosed with Noonan syndrome; 2 patients had minor cardiac malformations. Rapid deterioration occurred with mild respiratory infections with only supportive treatment available. Chest x-ray showed marked hyperinflation with interstitial infiltrate. CONCLUSIONS: This is the first long-term study of primary PL and will help counsel parents. Although fatal in the neonatal period, survival is possible if diagnosed past the neonatal period and improvement is expected.  相似文献   
52.

Objective

The aim of the study was to evaluate the technical feasibility and the postoperative course of aortic valve replacement through a ministernotomy.

Setting

The Montreal Heart Institute and the Hôpital Lariboisière, Paris, France.

Design

A case series from 2 institutions.

Patients

Fifty-one patients who underwent aortic valve replacement through a ministernotomy. The sternal incision was started at the level of the sternal notch extending down to the third or fourth intercostal space with a transverse section of the sternum at this level on both sides or limited to the right side (inverted T or L incision). Thirty-nine patients had aortic stenoses, 6 patients were operated for aortic insufficiency and 6 had mixed disease. The mean (and standard deviation) preoperative left ventricular ejection fraction was 0.56 (0.17).

Main outcome measures

Cardiac bypass time, complications and outcome.

Results

The patients received Carbomedics and St. Jude mechanical valves, Hancock and Carpentier–Edwards bioprostheses. Thirty-eight patients were administered antegrade and retrograde cardioplegia, 10 patients ante-grade and 3 retrograde blood cardioplegia only. The mean (and standard error) cardiopulmonary bypass time and aortic cross-clamp time were 104 (38) minutes and 72 (16) minutes respectively. Two patients (4%) died and 2 patients (4%) showed evidence of a stroke after the procedure. Hospital stay averaged 8 (5) days.

Conclusion

We conclude that aortic valve replacement can be done through a ministernotomy approach with perioperative results similar to those obtained through a conventional sternotomy.  相似文献   
53.
Background: Surgical residents used to work many hours. The European working time directive (EWTD) 2003/88/EG was created to protect young doctors from working too many hours. EWTD was implemented in Belgium on February 1st 2011. A decrease in working hours and improvement of surgical education was expected. Methods: Every resident was requested by the Faculty of Medicine to answer an ACC (Activities Coaching Context) questionnaire about his/her teaching hospital. The answers of surgical residents in all teaching hospitals, during the academic years before, during and after the implementation of the EWTD were used. Statistical analysis was performed with SPSS 20.

Results: Since implementation we noted a significant decrease in mean daily working time (MDWT) (p < 0,001). However, this MDWT stayed significantly longer in university hospitals (UH), even after implementation of EWTD (p = 0,024). Non-medical administrative workload (AW) did not change significantly (p = 0,531), but medical AW increased significantly after implementation (p = 0,050). Non-medical and medical AW were significantly higher in UH after implementation (p = 0,002 and p < 0,001). The opportunity to practice skills and also the perception of a good balance between working and learning did not change significantly after implementation (p = 0,200 and p = 0,819), but both were scored significantly better in non-UH (p < 0,001 and p = 0,052) regardless implementation of EWTD. Conclusions: Since implementation of EWTD there is a significant decrease in MDWT. However, AW has not decreased and is higher in UH. The main challenge for future surgical education will be to reduce AW in order to give surgical residents enough opportunities to practice their surgical skills without prolonging training time.  相似文献   
54.
In Huntington disease (HD), immune cells are activated before symptoms arise; however, it is unclear how the expression of mutant huntingtin (htt) compromises the normal functions of immune cells. Here we report that primary microglia from early postnatal HD mice were profoundly impaired in their migration to chemotactic stimuli, and expression of a mutant htt fragment in microglial cell lines was sufficient to reproduce these deficits. Microglia expressing mutant htt had a retarded response to a laser-induced brain injury in vivo. Leukocyte recruitment was defective upon induction of peritonitis in HD mice at early disease stages and was normalized upon genetic deletion of mutant htt in immune cells. Migration was also strongly impaired in peripheral immune cells from pre-manifest human HD patients. Defective actin remodeling in immune cells expressing mutant htt likely contributed to their migration deficit. Our results suggest that these functional changes may contribute to immune dysfunction and neurodegeneration in HD, and may have implications for other polyglutamine expansion diseases in which mutant proteins are ubiquitously expressed.  相似文献   
55.
56.
The purpose of this study was to determine the association between visceral adipose tissue (VAT) and all-cause mortality. The sample included 1089 white men and women 18–84 years of age from the Pennington Center Longitudinal Study, a prospective cohort of participants assessed between 1995 and 2008, and followed for mortality until 31 December 2009. Abdominal VAT was measured at the L4–L5 vertebral level using computed tomography. There were 27 deaths during an average of 9.1 years of follow-up. Abdominal VAT was significantly associated with mortality after adjustment for age, sex and year of examination (hazards ratio (HR) 1.46; 95% confidence interval 1.05–2.05). The association was stronger after the inclusion of abdominal subcutaneous adipose tissue (SAT), smoking status, alcohol consumption and leisure-time physical activity as additional covariates (HR 1.74; 1.17–2.59). Limiting the sample to participants who were free of stroke, heart disease and cancer at baseline reduced the strength of the relationship slightly (HR 1.62; 1.07–2.47). Abdominal SAT was not associated with mortality, either alone or in combination with VAT and other covariates. The results support the assertion that abdominal VAT is an important therapeutic target for obesity reduction efforts.  相似文献   
57.
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59.
ObjectiveTo provide Canadian gynaecologists with evidence-based direction for female genital cosmetic surgery in response to increasing requests for, and availability of, vaginal and vulvar surgeries that fall well outside the traditional realm of medically-indicated reconstructions.EvidencePublished literature was retrieved through searches of PubMed or MEDLINE, CINAHL, and The Cochrane Library in 2011 and 2012 using appropriate controlled vocabulary and key words (female genital cosmetic surgery). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date or language restrictions. Searches were updated on a regular basis and incorporated in the guideline to May 2012. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.ValuesThe quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table).  相似文献   
60.
Engineered nanomaterials (ENM) are a growing aspect of the global economy, and their safe and sustainable development, use, and eventual disposal requires the capability to forecast and avoid potential problems. This review provides a framework to evaluate the health and safety implications of ENM releases into the environment, including purposeful releases such as for antimicrobial sprays or nano-enabled pesticides, and inadvertent releases as a consequence of other intended applications. Considerations encompass product life cycles, environmental media, exposed populations, and possible adverse outcomes. This framework is presented as a series of compartmental flow diagrams that serve as a basis to help derive future quantitative predictive models, guide research, and support development of tools for making risk-based decisions. After use, ENM are not expected to remain in their original form due to reactivity and/or propensity for hetero-agglomeration in environmental media. Therefore, emphasis is placed on characterizing ENM as they occur in environmental or biological matrices. In addition, predicting the activity of ENM in the environment is difficult due to the multiple dynamic interactions between the physical/chemical aspects of ENM and similarly complex environmental conditions. Others have proposed the use of simple predictive functional assays as an intermediate step to address the challenge of using physical/chemical properties to predict environmental fate and behavior of ENM. The nodes and interactions of the framework presented here reflect phase transitions that could be targets for development of such assays to estimate kinetic reaction rates and simplify model predictions. Application, refinement, and demonstration of this framework, along with an associated knowledgebase that includes targeted functional assay data, will allow better de novo predictions of potential exposures and adverse outcomes.  相似文献   
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