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591.
592.
Forty Oxford medial unicompartmental arthroplasties (UCAs) were performed through a short incision medial to the patellar tendon, without dislocation of the patella, using updated instruments (Oxford Knee Phase III, Biomet Ltd., Bridgend, UK). The rate of recovery of these knees (measured by the time taken to achieve straight-leg raising, 70 degrees of flexion, and independent stair climbing) was compared with that of 20 Oxford UCAs performed through an open approach with dislocation of the patella. Both groups were compared with 40 AGC (Biomet) total knee arthroplasties performed for osteoarthritis during the same time period. The average rate of recovery after the short-incision UCA was twice as fast as after open UCA and 3 times as fast as after total knee arthroplasty. Accuracy of implantation, assessed from 11 variables seen on fluoroscopically centered postoperative radiographs, was the same after UCA by the short-incision approach as after the open approach, suggesting that the short-term advantage of increased speed of recovery was gained without affecting the long-term results. We now employ the short incision with the phase III instruments for all UCAs.  相似文献   
593.
594.
BACKGROUND: UK stroke mortality data suggest that the incidence of haemorrhagic stroke has fallen in the past 20 years, but these data do not include deaths of individuals aged 75 years or over. Trends in the older population might differ, since cause varies with age. Our aim was to investigate changes in the population-based incidence of intracerebral haemorrhage according to age and likely aetiology. METHODS: We used data from the Oxford Community Stroke Project (OCSP; 1981-86) and the Oxford Vascular Study (OXVASC; 2002-06) to investigate changes in the incidence of intracerebral haemorrhage with time, above and below age 75 years, together with associated risk factors and premorbid medications. Incidences were standardised to the 2001 census population of England and Wales. FINDINGS: In the population aged under 75 years the incidence of intracerebral haemorrhage decreased substantially (rate ratio 0.53, 95% CI 0.29-0.95; p=0.03), but the number of cases of intracerebral haemorrhage at all ages were similar in OXVASC and OCSP (52 vs 55 cases) as the proportion of cases occurring at 75 years and over tended to increase (2.0, 0.8-4.6; p=0.09). The incidence of intracerebral haemorrhage associated with premorbid hypertension (blood pressure >or=160/100 mm Hg) fell overall (0.37, 0.20-0.69; p=0.002), but the incidence of intracerebral haemorrhage associated with antithrombotic use was increased (7.4, 1.7-32; p=0.007). Above age 75 years the proportion of cases who were non-hypertensive with lobar bleeds and presumed to have had mainly amyloid-related haemorrhages, also increased (4.0, 1.1-17; p=0.003). INTERPRETATION: There has been a substantial fall in hypertension-associated intracerebral haemorrhage over the past 25 years, but not in the overall number of cases of intracerebral haemorrhage in older age-groups, in part due to a rise in intracerebral haemorrhage associated with antithrombotic use. These trends, along with the expected increase in prevalence of amyloid angiopathy with the ageing population, suggest that, in contrast to projections based on mortality data below age 75 years, absolute number of cases of intracerebral haemorrhage might increase in future.  相似文献   
595.
OBJECTIVES: To determine whether assessing seroprotection after influenza vaccine and administering booster vaccination where not achieved reduces hospitalization and death. To estimate the overall seroprotection rate of influenza vaccine.
DESIGN: A two-arm, partially blind, randomized, multicenter, parallel-group, controlled trial.
SETTING: Twenty-six care homes in three South London boroughs in fall 2004.
PARTICIPANTS: Two hundred seventy-seven elderly permanent care home residents meeting eligibility criteria.
INTERVENTION: Postvaccination blood samples were randomized to booster evaluation or no booster evaluation (control). If evaluation revealed inadequate seroprotection, a booster vaccine was administered.
MEASUREMENTS: Primary outcome was hospitalization to end April 2005; secondary outcomes were death, antibiotic use, and seroprotection.
RESULTS: Sixty percent of the controls and 41% of the booster evaluation group responded to routine vaccination. Booster vaccination where indicated increased seroprotection rates in the booster evaluation group to 66%. Treatment groups did not differ in any outcome measures in the intention-to-treat analysis (hospitalization odds ratio=1.02, 95% confidence interval=0.55–1.87). There was a tendency towards greater differences between groups in the per-protocol analysis than in the intention-to-treat analysis, particularly regarding seroprotection rates. The same effect was observed in the a priori exploratory analysis of residents not seroprotected after routine vaccination alone.
CONCLUSION: In a year without circulating influenza, there is no clinical benefit of administering a booster vaccine if routine trivalent vaccination fails to result in seroprotection. Hemagglutination titers rose in two strains postbooster vaccination but fell against the novel strain, Wyoming. The benefit of such a booster strategy when influenza is prevalent thus remains unc ertain.  相似文献   
596.
The influenza pandemic of 1918 caused unprecedented levels of morbidity and mortality in its 12-month period of circulation around the globe. The haemagglutinin molecule has been shown to affect the pathogenicity of some subtypes of influenza A viruses. Using a recombinant vaccinia system that allowed expression of the 1918 influenza haemagglutinin, we performed functional assays to assess the glycoprotein's involvement in determining the high pathogenicity of the 1918 virus. We show that in respect of expression levels, proteolytic processing, receptor-binding, membrane fusion and antigenic properties, the haemagglutinin of the 1918 virus is unremarkable when compared with the haemagglutinins of other 'early' H1 influenza viruses. This suggests that whilst the 1918 haemagglutinin, as a new/novel antigen in the human population, was responsible for the influenza pandemic its functions per se were not responsible for the high mortality and acute symptoms experienced by patients infected with the 1918 influenza virus.  相似文献   
597.

Background

We have developed a Trivalent DNA vaccine for influenza consisting of three plasmids expressing haemagglutinin from different seasonal influenza virus strains delivered using PMED™ (particle mediated epidermal delivery). We set out to determine whether this vaccine (with and without a molecular adjuvant DNA Encoded Immunostimulator-Labile Toxin (DEI-LT)) could protect subjects from a controlled influenza virus challenge.

Methods

Healthy adult subjects were screened for susceptibility to infection with influenza A/H3 Panama/2007/99 then vaccinated with 4 μg Trivalent influenza DNA vaccine, 2 μg Trivalent influenza DNA vaccine plus DEI-LT or placebo. Safety and serological responses to vaccination were assessed and on Day 56 subjects were challenged with A/H3 Panama/2007/99 virus.

Results

Vaccination with 4 μg Trivalent or 2 μg Trivalent/DEI-LT was well tolerated and induced antibody responses to two of the three influenza virus vaccine strains. Post challenge, subjects in the 4 μg Trivalent group (N = 27) showed reductions in disease symptoms and viral shedding compared to placebo (N = 27), with an overall vaccine efficacy of 41% (95% confidence interval (CI) = −1.5, 67.7) for ‘Any illness with or without fever’ and 53% for ‘Upper respiratory tract infection’ (95% CI = 8.0, 77.7).

Conclusion

It was concluded that PMED vaccination with 4 μg Trivalent influenza DNA vaccine was safe and elicited immunological responses that protected human subjects from influenza; this is the first report of protection of human subjects from disease by DNA vaccination.  相似文献   
598.
OBJECTIVES: To assess responsiveness and minimally important change (MIC) for the Manchester-Oxford foot questionnaire (MOXFQ) using anchor and distribution-based approaches. Responsiveness and estimates of minimal clinically important difference (MCID) and minimal detectable change are compared with those from the Short-Form 36 (SF-36) and American Orthopaedic Foot & Ankle Society (AOFAS) measures. METHODS: A prospective observational study of 91 consecutive patients (125 foot operations) undergoing hallux valgus surgery at an orthopaedic hospital. Pre- and 12 month post-surgery, patients completed the MOXFQ and SF-36, and foot surgeons assessed all four AOFAS scores corresponding to four regions of the foot. Transition items were asked about perceived changes compared with before surgery. RESULTS: Mean changes in all domains of each instrument were statistically significant, but foot-specific MOXFQ and AOFAS domains produced much larger effect sizes (>1) than any SF-36 domains, indicating superior responsiveness. Clear associations occurred between transition items and all MOXFQ and AOFAS scores, but with only one (physical function) SF-36 domain. Anchor and distribution-based approaches identified generally comparable measures of MIC, which for the MOXFQ and AOFAS domains were between 1 and 2 standard error of measurement. In metric terms, the MCIDs were 16, 12, and 24 for the MOXFQ Walking/standing, Pain, and Social Interaction domains, respectively. CONCLUSIONS: For hallux valgus surgery, the MOXFQ is highly responsive. Performance is comparable to the AOFAS and notably better than the generic SF-36. Study estimates of MIC for the MOXFQ are useful to inform sample-size calculations for future clinical trials.  相似文献   
599.
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