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41.
· Background: To investigate the potential of high-resolution ultrasound biomicroscopy (UBM) for studying the zonular apparatus of human beings in vivo. · Methods: Using transducer frequencies of 34 MHz and 50 MHz, criteria were developed to identify transcorneal and transscleral sections that allowed reproducible identification of the different fiber groups of the zonular architecture. For that purpose, 10 volunteers between the ages of 14 and 41 years underwent high-resolution ultrasound biomicroscopy under conditions of consensual far- and near-accommodation. The online video recordings of the respective UBM investigations were afterwards analyzed image by image. Good visibility of zonular fibers was obtained when the ultrasound wave propagation comprised an angle close to 90° with the fiber orientation and when the oscillations of the UBM scan had a strict radial orientation towards the limbus and avoided, simultaneously, the ciliary processes. · Results: In all the volunteers, high-resolution ultrasound biomicroscopy imaged the zonular fiber groups known from histology. In addition, it detected fibers that do not follow the course of the inner ciliary body surface but take a direct route from the ora serrata to the lens. It also demonstrated that fibers that seem to change direction at crossings with other fibers. Under conditions of near-accommodation, the zonular fibers showed signs of relaxation. · Conclusions: High-resolution ultrasound biomicroscopy seems well suited for in vivo investigations of the zonular apparatus and of accommodation in man. The results support the fundamental features of the Helmholtz theory on accommodation. Received: 8 June 1998 Revised version received: 7 September 1998 Accepted: 14 September 1998  相似文献   
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Purpose: To compare the efficacy of concomitant irradiation with mitomycin C and bleomycin in patients with inoperable head and neck carcinoma with radiotherapy alone.

Methods and materials: Between March 1991 and December 1993, 64 patients with inoperable head and neck carcinoma (41 with oropharyngeal site) were randomized to radiotherapy alone (group A) or radiotherapy combined with simultaneous application of mitomycin C and bleomycin (group B). In both groups patients were irradiated five times weekly with 2 Gy to a total dose of 66–70 Gy. The planned concomitant treatment in group B was: bleomycin 5 units twice a week IM, total dose 70 units, mitomycin C 15 mg/m2 IV after delivery of 10 Gy, and 10 mg/m2 IV on the last day of radiotherapy. To enhance the effect of these two drugs, patients received also nicotinamide, chlorpromazine, and dicoumarol.

Because significantly better results were achieved in arm B for patients with inoperable oropharyngeal carcinoma, the study was closed and such patients were after December 1993 routinely treated with the combined therapy (as in arm B). Until October 1996, we treated and followed up 48 such consecutive patients.

Results: Median follow-up of our study patients is 42 months. Complete remission (CR) rate in group A was 31% and in group B 59% (p = 0.04); disease-free survival (DFS) in group A was 8% and in group B 37% (P = 0.01); and overall survival (OS) was 7% in group A and 26% in group B (p = 0.08). CR rate for patients with oropharyngeal carcinoma was 29% in group A (N = 21) and 75% in group B (N = 20) (p = 0.007); DFS in group A was 10% and in group B 48% (p = 0.001); and the OS was 10% in group A and 38% in group B (p = 0.019). In patients with inoperable oropharyngeal carcinoma treated after December 1993, complete remission was achieved in 32/48 (67%, 95% CI: 52%–80%). DFS at the median follow-up of 14 months was 60% (95% CI 43–77%) and OS 58% (95% CI 42–74%).

Conclusion: From the results of our study it seems that the concomitant treatment significantly improves CR rate, DFS, and OS in patients with inoperable oropharyngeal carcinoma in comparison with radiotherapy alone.  相似文献   

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Brazil is blessed with a great biodiversity, which constitutes one of the most important sources of biologically active compounds, even if it has been largely underexplored. As is the case of the Amazon and Atlantic rainforests, the Brazilian marine fauna remains practically unexplored in the search for new biologically active natural products. Considering that marine organisms have been shown to be one of the most promising sources of new bioactive compounds for the treatment of different human diseases, the 8000 km of the Brazilian coastline represents a great potential for finding new pharmacologically active secondary metabolites. This review presents the status of marine natural products chemistry in Brazil, including results reported by different research groups with emphasis on the isolation, structure elucidation, and evaluation of biological activities of natural products isolated from sponges, ascidians, octocorals, and Opistobranch mollusks. A brief overview of the first Brazilian program on the isolation of marine bacteria and fungi, directed toward the production of biologically active compounds, is also discussed. The current multidisciplinary collaborative program under development at the Universidade de S?o Paulo proposes to establish a new paradigm toward the management of the Brazilian marine biodiversity, integrating research on the species diversity, ecology, taxonomy, and biogeography of marine invertebrates and microorganisms. This program also includes a broad screening program of Brazilian marine bioresources, to search for active compounds that may be of interest for the development of new drug leads.  相似文献   
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BackgroundCritical illness may lead to activation of the sympathetic system. The sympathetic stimulation may be further increased by exogenous catecholamines, such as vasopressors and inotropes. Excessive adrenergic stress has been associated with organ dysfunction and higher mortality. β-Blockers may reduce the adrenergic burden, but they may also compromise perfusion to vital organs thus worsening organ dysfunction. To assess the effect of treatment with β-blockers in critically ill adults, we conducted a systematic review and meta-analysis of randomized controlled trials.Materials and methodsWe conducted a search from three major databases: Ovid Medline, the Cochrane Central Register for Controlled Trials and Scopus database. Two independent reviewers screened, selected, and assessed the included articles according to prespecified eligibility criteria. We assessed risk of bias of eligible articles according to the Cochrane guidelines. Quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.ResultsSixteen randomized controlled trials comprising 2410 critically ill patients were included in the final review. A meta-analysis of 11 trials including 2103 patients showed a significant reduction in mortality in patients treated with β-blockers compared to control (risk ratio 0.65, 95%CI 0.53–0.79; p < .0001). There was no significant difference in mean arterial pressure or vasopressor load. Quality of life, biventricular ejection fraction, blood lactate levels, cardiac biomarkers and mitochondrial function could not be included in meta-analysis due to heterogenous reporting of outcomes.ConclusionsIn this systematic review we found that β-blocker treatment reduced mortality in critical illness. Use of β-blockers in critical illness thus appears safe after initial hemodynamic stabilization. High-quality RCT’s are needed to answer the questions concerning optimal target group of patients, timing of β-blocker treatment, choice of β-blocker, and choice of physiological and hemodynamic parameters to target during β-blocker treatment in critical illness.

KEY MESSAGES

  • A potential outcome benefit of β-blocker treatment in critical illness exists according to the current review and meta-analysis. Administration of β-blockers to resuscitated patients in the ICU seems safe in terms of hemodynamic stability and outcome, even during concomitant vasopressor administration. However, further studies, preferably large RCTs on β-blocker treatment in the critically ill are needed to answer the questions concerning timing and choice of β-blocker, patient selection, and optimal hemodynamic targets.
  相似文献   
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The consumption of ultra-processed food (UPF)-rich diets represents a potential threat to human health. Considering maternal diet adequacy during pregnancy is a major determinant for perinatal health outcomes, this study aimed to systematically review and meta-analyze studies investigating the association between maternal consumption of a UPF-rich diet and perinatal outcomes. Conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, five electronic databases and gray literature using Google Scholar and ProQuest Dissertations and Theses Global were searched up to 31 May 2022. No restrictions were applied on language and publication date. Two reviewers independently conducted the study selection and data extraction process. Meta-analysis was conducted according to the random-effects model. In total, 61 studies were included in the systematic review and the overall population comprised 698,803 women from all gestational trimesters. Meta-analysis of cohort studies showed that maternal consumption of UPF-rich diets was associated with an increased risk of gestational diabetes mellitus (odds ratio (OR): 1.48; 95% confidence interval (CI): 1.17, 1.87) and preeclampsia (OR: 1.28; 95% CI: 1.15, 1.42). Neonatal outcomes showed no association. The overall GRADE quality of the evidence for the associations was very low. The findings highlight the need to monitor and reduce UPF consumption, specifically during the gestational period, as a strategy to prevent adverse perinatal outcomes.  相似文献   
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CoronaVirus disease-2019 has changed the delivery of health care worldwide and the pandemic has challenged oncologists to reorganize cancer care. Recently, progress has been made in the field of precision medicine to provide to patients with cancer the best therapeutic choice for their individual needs. In this context, the Foundation Medicine (FMI)-Liquid@Home project has emerged as a key weapon to deal with the new pandemic situation. FoundationOne Liquid Assay (F1L) is a next-generation sequences-based liquid biopsy service, able to detect 324 molecular alterations and genomic signatures, from May 2020 available at patients’ home (FMI-Liquid@Home). We analyzed time and costs saving for patients with cancer, their caregivers and National Healthcare System (NHS) with FMI-Liquid@Home versus F1L performed at our Department. Different variables have been evaluated. Between May 2020 and August 2021, 218 FMI-Liquid@Home were performed for patients with cancer in Italy. Among these, our Department performed 153 FMI-Liquid@Home with the success rate of 98% (vs. 95% for F1L in the hospital). Time saving for patients and their caregivers was 494.86 and 427.36 hours, respectively, and costs saving was 13 548.70€. Moreover, for working people these savings were 1084.71 hours and 31 239.65€, respectively. In addition, the total gain for the hospital was 163.5 hours and 6785€, whereas for NHS was 1084.71 hours and 51 573.60€, respectively. FMI-Liquid@Home service appears to be useful and convenient allowing time and costs saving for patients, caregivers, and NHS. Born during the COVID-19 pandemic, it could be integrated in oncological daily routine in the future. Therefore, additional studies are needed to better understand the overall gain and how to integrate this service in different countries.  相似文献   
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Bone is constantly controlled by a balance between osteoblastic bone formation and osteoclastic bone resorption. Liquiritigenin is a plant‐derived flavonoid and has various pharmacological effects, such as antioxidative, antitumor, and antiinflammatory effects. Here, we show that liquiritigenin has dual effects on the proliferation of bone cells, regarding the promotion of osteoblast differentiation and the inhibition of osteoclast differentiation. Liquiritigenin‐treated murine osteoblastic MC3T3‐E1 cells showed an increased alkaline phosphatase activity and enhanced phosphorylation of Smad1/5 compared with untreated cells. Moreover, liquiritigenin inhibited osteoclast differentiation, its bone‐resorption activity through slightly decreased the phosphorylation of extracellular signal‐regulated kinase, c‐Jun N‐terminal kinase, and inhibitor of nuclear factor kappa Bα; however, the phosphorylation of Akt and p38 slightly increased in bone marrow‐derived osteoclasts. The expression levels of the osteoclast marker proteins nuclear factor of activated T‐cell cytoplasmic‐1, Src, and cathepsin K diminished. These results suggest that liquiritigenin may be useful as a therapeutic and/or preventive agent for osteoporosis or inflammatory bone diseases. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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