全文获取类型
收费全文 | 3750篇 |
免费 | 344篇 |
国内免费 | 75篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 75篇 |
妇产科学 | 23篇 |
基础医学 | 343篇 |
口腔科学 | 56篇 |
临床医学 | 268篇 |
内科学 | 1146篇 |
皮肤病学 | 183篇 |
神经病学 | 213篇 |
特种医学 | 75篇 |
外科学 | 155篇 |
综合类 | 603篇 |
预防医学 | 600篇 |
眼科学 | 31篇 |
药学 | 160篇 |
1篇 | |
中国医学 | 157篇 |
肿瘤学 | 66篇 |
出版年
2024年 | 20篇 |
2023年 | 118篇 |
2022年 | 177篇 |
2021年 | 275篇 |
2020年 | 249篇 |
2019年 | 327篇 |
2018年 | 208篇 |
2017年 | 159篇 |
2016年 | 156篇 |
2015年 | 115篇 |
2014年 | 221篇 |
2013年 | 212篇 |
2012年 | 196篇 |
2011年 | 210篇 |
2010年 | 160篇 |
2009年 | 147篇 |
2008年 | 145篇 |
2007年 | 138篇 |
2006年 | 143篇 |
2005年 | 99篇 |
2004年 | 98篇 |
2003年 | 58篇 |
2002年 | 67篇 |
2001年 | 43篇 |
2000年 | 45篇 |
1999年 | 35篇 |
1998年 | 21篇 |
1997年 | 24篇 |
1996年 | 20篇 |
1995年 | 27篇 |
1994年 | 34篇 |
1993年 | 19篇 |
1992年 | 12篇 |
1991年 | 11篇 |
1990年 | 23篇 |
1989年 | 17篇 |
1988年 | 27篇 |
1987年 | 14篇 |
1986年 | 11篇 |
1985年 | 11篇 |
1984年 | 15篇 |
1983年 | 12篇 |
1982年 | 7篇 |
1981年 | 4篇 |
1980年 | 5篇 |
1979年 | 9篇 |
1978年 | 3篇 |
1977年 | 6篇 |
1976年 | 7篇 |
1972年 | 4篇 |
排序方式: 共有4169条查询结果,搜索用时 15 毫秒
81.
《Clínica e investigación en ginecología y obstetricia》2024,51(1):100910
ObjectiveThe objectives were to estimate the performance of the IOTA-ADNEX model test after its incorporation into the ultrasound tests of our third-grade hospital gynecology service, as well as to assess whether its capacity of accuracy is modified when taking into account the patient's menopausal status.MethodsA cross-sectional study was conducted to clinically evaluate the diagnostic performance of the IOTA-ADNEX model test, which was performed between January 2016 and December 2021. The study included 573 women with an adnexal injury who underwent surgical excision within 180 days after ultrasound diagnosis and histological confirmation (gold standard). After the ultrasound exam, the injuries were classified using the ADNEX model. The study estimated the area under the receiver-operating-characteristics curve (AUC) of the ADNEX model for classifying between benign and malignant adnexal masses and compared the performance by menopausal state. Sensitivity and specificity were determined for different cut-off points.ResultsOut of the 573 women, 183 (31.9%) had a malignant tumor. The AUC of the ADNEX model for differentiating between benign and malignant adnexal masses at the time of ultrasound examination was 0.92 and the best malignancy threshold, detected by Youden index, was 22.5%. At this cut-off, the sensitivity of the ADNEX model was 91.8% and the specificity was 76.4%. However, it varies according to menopausal status: in the group of pre-menopausal patient, sensitivity was 86.1% (95% CI, 85.4%–86.8%) and specificity was 81.3% (95% CI, 85.4%–86.8%). In the postmenopausal group, sensitivity was 96.1% (95% CI, 95.6%–96.7%) and specificity was 68.5% (95% CI, 68.1%–68.8%).ConclusionsThe IOTA-ADNEX model is a reliable diagnostic tool to discard ovarian cancer. However, the accuracy of the test, at the same cut-off point, varies according to the menopausal state of the patient so it may be important to take it into account when taking decisions in clinical practice. 相似文献
82.
《Journal of Cardiovascular Computed Tomography》2022,16(5):397-403
BackgroundPretest probability (PTP) calculators utilize epidemiological-level findings to provide patient-level risk assessment of obstructive coronary artery disease (CAD). However, their limited accuracies question whether dissimilarities in risk factors necessarily result in differences in CAD. Using patient similarity network (PSN) analyses, we wished to assess the accuracy of risk factors and imaging markers to identify ≥50% luminal narrowing on coronary CT angiography (CCTA) in stable chest-pain patients.MethodsWe created four PSNs representing: patient characteristics, risk factors, non-coronary imaging markers and calcium score. We used spectral clustering to group individuals with similar risk profiles. We compared PSNs to a contemporary PTP score incorporating calcium score and risk factors to identify ≥50% luminal narrowing on CCTA in the CT-arm of the PROMISE trial. We also conducted subanalyses in different age and sex groups.ResultsIn 3556 individuals, the calcium score PSN significantly outperformed patient characteristic, risk factor, and non-coronary imaging marker PSNs (AUC: 0.81 vs. 0.57, 0.55, 0.54; respectively, p ?< ?0.001 for all). The calcium score PSN significantly outperformed the contemporary PTP score (AUC: 0.81 vs. 0.78, p ?< ?0.001), and using 0, 1–100 and ?> ?100 cut-offs provided comparable results (AUC: 0.81 vs. 0.81, p ?= ?0.06). Similar results were found in all subanalyses.ConclusionCalcium score on its own provides better individualized obstructive CAD prediction than contemporary PTP scores incorporating calcium score and risk factors. Risk factors may not be able to improve the diagnostic accuracy of calcium score to predict ≥50% luminal narrowing on CCTA. 相似文献
83.
Li Zhang Yuli Kang Shujun Chen Li Wang Min Jiang Leihong Xiang 《Journal of dermatological science》2019,93(2):92-100
Background
Vitiligo is an autoimmune disease with varying pathological features. Activation of the CCL20-CCR6 axis plays an important role in chronic inflammatory diseases. However, whether CCL20-CCR6 and Th1/17 cells are indicative of active vitiligo is unclear.Objective
To investigate the potential role of CCL20 and the involvement of Th1/17 and Tc1/17 cells in the mechanism in vitiligo.Methods
One hundred patients with vitiligo, and 20 healthy controls were included. The serum and blister fluid IL-17, IFN-γ, CCL20, and CXCL10 were studied using enzyme-linked immunosorbent assays. The numbers of Th1/17 cells and Tc1/17 cells in circulation were quantified using flow cytometry. CCR6 mRNA in peripheral blood mononuclear cells (PBMCs) was analyzed by real-time polymerase chain reaction and the protein level was confirmed by western blotting. CCR6 and CCL20 expression in lesions was analyzed by immunohistochemistry.Results
The serum CCL20 level was significantly elevated in patients with vitiligo. The level of serum CCL20 was higher in active than in the stable stage, which correlated positively with the Vitiligo European Task Force spreading score and the Vitiligo Area Scoring Index score. Patients with active vitiligo had elevated numbers of circulating Th1/17 cells and Tc1/17 cells, and upregulated expression of CCR6 in PBMCs and lesions. After effective treatment, the level of CCL20 in sera and blister fluid was significantly decreased, as were the numbers of circulating Th1/17 cells and Tc1/17 cells.Conclusion
CCL20 might be a vital biomarker of active vitiligo, and circulating Th1/17 and Tc1/17 cells are involved in the pathogenesis of vitiligo. 相似文献84.
A number of initiatives are underway in the United States in response to the 2009 critique of forensic science by a National Academy of Sciences committee. This article provides a broad review of activities including efforts of the White House National Science and Technology Council Subcommittee on Forensic Science and a partnership between the Department of Justice (DOJ) and the National Institute of Standards and Technology (NIST) to create the National Commission on Forensic Science and the Organization of Scientific Area Committees. These initiatives are seeking to improve policies and practices of forensic science. Efforts to fund research activities and aid technology transition and training in forensic science are also covered.The second portion of the article reviews standards in place or in development around the world for forensic DNA. Documentary standards are used to help define written procedures to perform testing. Physical standards serve as reference materials for calibration and traceability purposes when testing is performed. Both documentary and physical standards enable reliable data comparison, and standard data formats and common markers or testing regions are crucial for effective data sharing. Core DNA markers provide a common framework and currency for constructing DNA databases with compatible data. Recent developments in expanding core DNA markers in Europe and the United States are discussed. 相似文献
85.
《Health & place》2022
This study aimed to understand the perceived effects of the COVID-19 pandemic on physical activity, recreation walking, and use of recreational facilities; and if the COVID-19 pandemic amplified disparities in physical activity, recreational walking, and use of recreational facilities related to the levels of neighborhood disadvantage. Recreational walking and the use of neighborhood streets and green spaces significantly decreased in high deprivation areas but not in low deprivation areas during the pandemic. While COVID-19 has negatively affected overall recreational activities, the inequitable impact on recreational walking and use of outdoor recreational facilities has been more evident in disadvantaged neighborhoods with greater deprivation. 相似文献
86.
87.
88.
刘苏苏茅宁莹 《中国卫生质量管理》2021,(7):022-24
目的分析江苏省卫生地方标准发展现状,提出优化建议。方法采用数据库检索方式进行分析。结果江苏省卫生地方标准制定主体以卫生行政部门为主,技术标准数量较多。75.00%的标准标龄较短,标准更新较少。江苏省卫生地方标准以职业健康领域标准为主,存在总体标准数量较少、分类依据不清晰、缺乏系统性及全面性指导、第三方主体作用不突出、标准重制定而轻执行等问题。结论江苏省卫生地方标准在促进江苏省卫生领域发展,完善卫生健康管理体系方面发挥着重要作用。建议建立健全标准化工作政策法规,强化标准实施,建立标准专业化队伍,推动行业标准化工作发展。 相似文献
89.
Matthias Aurich Patrick Fuchs Matthias Müller-Hennessen Lorenz Uhlmann Matthias Niemers Sebastian Greiner Tobias Täger Kristof Hirschberg Philipp Ehlermann Benjamin Meder Lutz Frankenstein Evangelos Giannitsis Hugo A. Katus Derliz Mereles 《Journal of the American Society of Echocardiography》2018,31(6):733-742
90.
《Acta oto-laryngologica》2012,132(11):939-947
AbstractBackground: Inner gene therapy offers great promises as a potential treatment for hearing loss.Aims/objectives: One of the critical determinants of the success of inner ear gene therapy is to find a delivery method which results in consistent transduction efficiency of targeted cell types while minimizing hearing loss.Material and methods: Surgery was performed only in the right ear of each Bama miniature pig, and the left ear served as a control. The gene delivery to inner ear via round window membrane (RWM) and posterior semicircular canal (PSC) approach was performed with the viral vector AAV1-CMV-GFP.Results: The gene delivery through RWM and the PSC (canalostomy) is able to perfuse the inner ear.Conclusions and significance: The easy anatomic identification of the PSC, as to RWM, as well as minimal manipulation of the temporal bone required, make this surgical approach an attractive option for inner ear gene delivery in big animal model. 相似文献