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991.
Macular hole formation is a well-known complication following ocular trauma. Less commonly recognised is the spontaneous closure of such holes.A 27-year-old man presented with a history of blunt trauma to his left eye. Eye evaluation showed conjunctival laceration, diffuse retinal oedema and multiple retinal haemorrhages in that eye. A month later, he developed a full thickness macular hole. Two months later, there was spontaneous complete closure of the full-thickness macular hole in the left eye as confirmed on optical coherence tomography.Spontaneous closure of hole is not uncommon. Observation for a period of up to 12 months is a reasonable management option. Macular hole surgery for traumatic macular holes may be delayed in such cases. 相似文献
992.
Steedman M Abouammoh M Sharma S 《Canadian journal of ophthalmology. Journal canadien d'ophtalmologie》2012,47(1):66-71
ObjectiveTo evaluate the effectiveness of a novel multimedia learning tool (MMLT) for teaching a method of approaching common ophthalmologic presentations.DesignRandomized clinical study.Participants25 second-year medical students at Queen's University.MethodsWe evaluated 2 MMLTs pertaining to common ophthalmologic presentations—acute visual loss and cataract—through the use of a randomized clinical study. Subjects were randomized either to watch a short-form video or to read a textbook excerpt for both cataract and acute visual loss. If randomized to one MMLT for the first module, the subject was allocated to the other modality for the second module. The main outcomes of interest were knowledge retention as measured by a short multiple-choice questionnaire, efficiency, and user preference.ResultsA trend was noted whereby subjects randomized to an MMLT had higher composite scores on multiple-choice questionnaires (mean score MMLT = 75.2% vs text = 67.5%; t test = 1.535; df = 22; p value = 0.139). Additionally, those who watched an MMLT spent 72% less time reviewing the education content (29 min vs 8 min; t test = 3.955, p value = 0.0003). Of the sample, 87% preferred the MMLT over the text.ConclusionsMMLTs can significantly reduce learning time without sacrificing knowledge retention in undergraduate students of ophthalmology. 相似文献
993.
Erdheim-Chester disease (ECD) is an exceedingly rare, disseminated non-Langerhan cell histiocytosis with multisystem involvement, having characteristic sclerotic skeletal lesions. We present an unusual case primarily manifesting as an extensive orbital disease, with low-grade systemic involvement. Owing to its rarity and therefore lack of general awareness it remains a difficult clinical and pathologic diagnosis. Immuno-histochemistry of the biopsy specimen is diagnostic. 相似文献
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996.
PK Shah V Narendran U Selvaraj P Guhan SK Saxena A Dash M Astrahan 《Indian journal of ophthalmology》2012,60(4):289-295
Context:
To analyze the results of episcleral plaque brachytherapy using indigenous Bhabha Atomic Research Centre (BARC) Iodine-125 Ocu-Prosta seeds for the management of intraocular tumors from a single institute.AIM:
To report our initial experience and learning curve on the use of ‘BARC I-125 Ocu-Prosta seeds’ for the management of intraocular tumors such as choroidal melanomas, retinoblastomas and vasoproliferative tumors (VPT).Materials and Methods:
We retrospectively reviewed 13 eyes of 13 patients who underwent ophthalmic brachytherapy between May 2008 to March 2012. Nine cases had choroidal melanomas; three had retinoblastomas while one case had VPT.Results:
For choroidal melanomas the average apical diameter before brachytherapy was 7.6 mm and average largest basal diameter was 12.1 mm, respectively, which reduced to 4.2 mm and 7.7 mm after the procedure at an average follow-up of 24 months (range 10-43 months). Retinoblastoma and VPT also showed good regression after brachytherapy.Conclusion:
Plaque radiotherapy using 125I seeds can be performed under peribulbar anesthesia and provides a viable option for the management of intraocular cancer with minimal invasiveness and surgical complications. Patients in our studies experienced excellent local tumor control. With the availability of indigenous ‘BARC I-125 Ocu-Prosta seeds’ locally, cost effective ophthalmic brachytherapy can be performed in India. 相似文献997.
VanderWeele TJ Asomaning K Tchetgen Tchetgen EJ Han Y Spitz MR Shete S Wu X Gaborieau V Wang Y McLaughlin J Hung RJ Brennan P Amos CI Christiani DC Lin X 《American journal of epidemiology》2012,175(10):1013-1020
Genome-wide association studies have identified variants on chromosome 15q25.1 that increase the risks of both lung cancer and nicotine dependence and associated smoking behavior. However, there remains debate as to whether the association with lung cancer is direct or is mediated by pathways related to smoking behavior. Here, the authors apply a novel method for mediation analysis, allowing for gene-environment interaction, to a lung cancer case-control study (1992-2004) conducted at Massachusetts General Hospital using 2 single nucleotide polymorphisms, rs8034191 and rs1051730, on 15q25.1. The results are validated using data from 3 other lung cancer studies. Tests for additive interaction (P = 2 × 10(-10) and P = 1 × 10(-9)) and multiplicative interaction (P = 0.01 and P = 0.01) were significant. Pooled analyses yielded a direct-effect odds ratio of 1.26 (95% confidence interval (CI): 1.19, 1.33; P = 2 × 10(-15)) for rs8034191 and an indirect-effect odds ratio of 1.01 (95% CI: 1.00, 1.01; P = 0.09); the proportion of increased risk mediated by smoking was 3.2%. For rs1051730, direct- and indirect-effect odds ratios were 1.26 (95% CI: 1.19, 1.33; P = 1 × 10(-15)) and 1.00 (95% CI: 0.99, 1.01; P = 0.22), respectively, with a proportion mediated of 2.3%. Adjustment for measurement error in smoking behavior allowing up to 75% measurement error increased the proportions mediated to 12.5% and 9.2%, respectively. These analyses indicate that the association of the variants with lung cancer operates primarily through other pathways. 相似文献
998.
Traditionally, qualitative studies are founded on interpretative and constructive epistemology. The process of data collection in these studies is longer and intensive. This helps to build a strong rapport with the community, hence enabling to capture the field as naturally as possible. These characteristics provide an ample scope to take care of quality and validity of data. However, in applied situations, data collection is often a truncated activity. This robs away a number of taken-for-granted strengths of traditional qualitative research methods: No time is spent on rapport building; holism is left behind, instead we engage in selection; we focus narrowly on specific phenomenon of concern, divorced from its context; analysis does not evolve out of an iterative process. In this paper, we aim to discuss some of the issues related to rigor and quality of such studies and strategies available to address them. 相似文献
999.
Byakodi R Byakodi S Hiremath S Byakodi J Adaki S Marathe K Mahind P 《Journal of community health》2012,37(2):316-319
Oral cancer is one of the most fatal health problems faced by the mankind today. In India, because of cultural, ethnic, geographic
factors and the popularity of addictive habits, the frequency of oral cancer is high. It ranks number one in terms of incidence
among men and third among women. Several factors like tobacco and tobacco related products, alcohol, genetic predisposition
and hormonal factors are suspected as possible causative factors. Hence the study was designed to determine the prevalence
of Oral Cancer in patients who attended the outpatient department, at Bharati Vidyapeeth Deemed University Dental College
Sangli India during a period of 24 months in 2009–2010. Further various modes of tobacco and alcohol consuming habit were
assessed along with the site of occurrence of oral cancer. About 35,122 subjects belonging to a semi-urban district of Sangli
in Western Maharashtra (India) were screened. Tobacco and alcohol consumption was the common habit among the study population.
Out of these about 112 cases showed Oral Cancer. The prevalence of Oral Cancer was 1.12%. Statistical analysis was done using
the SPSS software 11. The findings in the present study reveal a high prevalence of Oral Cancer and a rampant misuse of variety
of addictive substances in the community. Close follow up and systematic evaluation is required in this population. Education
about ill effects of tobacco and alcohol consumption is necessary at a broader scale. There is an urgent need for awareness
programs involving the community health workers, dentists and allied medical professionals. 相似文献
1000.