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INTRODUCTION: The anatomic arrangement of pulmonary veins (PVs) is variable. No prior studies have quantitatively analyzed the effects of segmental ostial ablation on the PVs. The aim of this study was to determine the effect of segmental ostial radiofrequency ablation on PV anatomy in patients with atrial fibrillation (AF). METHODS AND RESULTS: Three-dimensional models of the PVs were constructed from computed tomographic (CT) scans in 58 patients with AF undergoing segmental ostial ablation to isolate the PVs and in 10 control subjects without a history of AF. CT scans were repeated approximately 4 months later. PV and left atrial dimensions were measured with digital calipers. Four separate PV ostia were present in 47 subjects; 3 ostia were present in 2 subjects; and 5 ostia were present in 9 subjects. The superior PVs had a larger ostium than the inferior PVs. Patients with AF had a larger left atrial area between the PV ostia and larger ostial diameters than the controls. Segmental ostial ablation resulted in a 1.5 +/- 3.2 mm narrowing of the ostial diameter. A 28% to 61% focal stenosis was present 7.6 +/- 2.2 mm from the ostium in 3% of 128 isolated PVs. There were no instances of symptomatic PV stenosis during a mean follow-up of 245 +/- 105 days. CONCLUSION: CT of the PVs allows identification of anatomic variants prior to catheter ablation procedures. Segmental ostial ablation results in a significant but small reduction in ostial diameter. Focal stenosis occurs infrequently and is attributable to delivery of radiofrequency energy within the PV.  相似文献   
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Several limitations of the use of embryonated eggs and the threat of pandemics have highlighted the need for other platforms for the production of influenza vaccines. We report the indigenous development and pre-clinical testing of an MDCK-based H1N1 pandemic influenza vaccine HNVAC from India. The cell bank and virus seed were characterized extensively. The cells were characterized by PCR, electron microscopy, and karyotyping, and found to be of female canine epithelial origin. The virus was confirmed by neutralization, haemagglutination inhibition, neuraminidase inhibition, and PCR and nucleotide sequencing. Adventitious agent testing was performed by both in vitro and in vivo studies. The in vitro studies included culturing, haemadsorption, haemagglutination, PCR and RT-PCR, whereas in vivo studies included passage in embryonated eggs and in laboratory animals. Both cell bank and virus seed were free of adventitious agents. MDCK cell lysates as well as cellular DNA did not produce tumours in newborn or adult laboratory animals. The bioprocess parameters were standardized to recover antigen with minimal levels of process-related impurities. The vaccine bulk was tested for the presence of specific antigen, and quantified by single radial immunodiffusion. Finally, non-adjuvanted and aluminium hydroxide adjuvanted vaccine formulations were found to be safe in preclinical toxicity studies in mice, rats, guinea pigs and rabbits, and immunogenic in mice and rabbits. This is the first and only cell culture-based influenza vaccine platform developed in any developing country.  相似文献   
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The aim of this anatomical study was to investigate the genial spinal canal histologically and to reconstruct it three-dimensionally to improve understanding of its anatomy and to reveal any differences between dentate and edentulous specimens. Two tissue blocks from the mandible between the left and right second incisors, one dentate and one edentulous, were fixed in 4.5% formaldehyde, decalcified and embedded in paraffin. Serial histological sections were prepared, stained with Azan and examined microscopically. Additionally, three-dimensional models of the blocks were reconstructed using microphotographs of the sections. The genial spinal canal in the dentate specimen contained a neurovascular bundle, which branched into a nerve innervating the incisor and a neurovascular bundle, whereas that in the edentulous specimen contained some nerves for vestibular gingival innervation and a vascular bundle. The results suggest differences in the genial spinal canal between dentate and edentulous mandibles. Further research is needed to confirm this finding. Clin. Anat., 33:1102–1108, 2020. © 2019 Wiley Periodicals, Inc.  相似文献   
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Preventing suicide is a global priority, and staff training is a core prevention strategy. However, frontline pressures make translating training into better care and better outcomes difficult. The aim of the paper was to highlight challenges in suicide risk assessment and management and introduce training frameworks to assist with mindful practice so professionals can strike a balance between risk and recovery. We combined the scientific literature with contemporary practice from two successful initiatives from Cambridgeshire, UK: 333 – a recovery‐oriented model of inpatient/community crisis care and PROMISE – a programme to reduce coercion in care by enhancing patient experience. The resulting PROTECT (PROactive deTECTion) frameworks operationalize ongoing practice of relational safety in these programmes. PROTECT is a combination of novel concepts and adaptations of well‐established therapeutic approaches. It has four training frameworks: AWARE for reflection on clinical decisions; DESPAIR for assessment; ASPIRE for management; and NOTES for documentation. PROTECT aims to improve self‐awareness of mental shortcuts and risk‐taking thresholds and increase rigour through time‐efficient cross‐checks. The training frameworks should support a relational approach to self‐harm/suicide risk detection, mitigation, and documentation, making care safer and person‐centred. The goal is to enthuse practitioners with recovery‐oriented practice that draws on the strengths of the person in distress and their natural circle of support. It will provide the confidence to engage in participatory approaches to seek out unique individualized solutions to the overwhelming psychological pain of suicidal distress. Future collaborative research with people with lived and carer experience is needed for fine‐tuning.  相似文献   
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Loss of heterozygosity (LOH) in chromosome 6 in human squamous cervical carcinomas was analyzed in the long and short arms of the chromosome using 3 pairs of primers each. In all cases, normal adjacent tissue was used as control. Among 51 cases analyzed, we identified LOH or microsatellite instability in 23% using primer D6S291 (located at position 6p21.3) and in 11% using primers D6S308 (6q16.3–6q27) and D6S270 (6q22.3–6q23.2). On the contrary, no significant LOH or genomic instabilities were detected with primers D6S306 (6p22.3–6p21.2), D6S299 (6p22.3–6p21.3) and D6S287 (6q21–6q23.3). Our results thus suggest the existence of instable loci at 3 regions of chromosome 6. Whether these loci contain putative tumor-suppressor genes or genes involved in cell cycle control remains unknown. © 1996 Wiley-Liss, Inc.  相似文献   
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Acanthocystis turfacea chlorella virus (ATCV-1), a prospective member of the family Phycodnaviridae, genus Chlorovirus, infects a unicellular, eukaryotic, chlorella-like green alga, Chlorella SAG 3.83, that is a symbiont in the heliozoon A. turfacea. The 288,047-bp ATCV-1 genome is the first virus to be sequenced that infects Chlorella SAG 3.83. ATCV-1 contains 329 putative protein-encoding and 11 tRNA-encoding genes. The protein-encoding genes are almost evenly distributed on both strands and intergenic space is minimal. Thirty-four percent of the viral gene products resemble entries in the public databases, including some that are unexpected for a virus. For example, these unique gene products include ribonucleoside-triphosphate reductase, dTDP-d-glucose 4,6 dehydratase, potassium ion transporter, aquaglyceroporin, and mucin-desulfating sulfatase. Comparison of ATCV-1 protein-encoding genes with the prototype chlorella virus PBCV-1 indicates that about 80% of the ATCV-1 genes are present in PBCV-1.  相似文献   
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